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Pregnancy and the orthopaedic patient
GENERAL ORTHOPAEDICS
Pregnancy and the orthopaedic patient
uterus and its contents alters the body’s centre of gravity, moving it anteriorly. This applies mechanical stress upon the axial skeleton, particularly in the lumbar spine. Heckman et al report that 70% of women experience low back pain at some point during pregnancy.1 Hormones such as relaxin, released during pregnancy, have in the past been theorized to affect joint laxity. Recent evidence suggests relaxin may not be responsible for this joint laxity, however.2 Irrespective of the precise mechanism involved, joint laxity is common in pregnancy. It begins from the 10th week of gestation and may last for up to 4e12 weeks postpartum.3 Furthermore, a number of haemodynamic changes occur that requires careful consideration in the orthopaedic trauma situation. Cardiac output increases by 35e50% over the first 10 weeks of gestation. This increase is maintained throughout the pregnancy. Circulating maternal blood volume also increases by 40e50%. A dilutional anaemia exists, since red blood cell mass does not increase to the same extent as this increase in plasma volume. A small decrease in haematocrit is observed.4 These changes may serve to mask the true extent of blood loss in the trauma setting. Blood loss of up to 2 L may therefore not be immediately apparent, since the mean arterial pressure remains stable.5 The gravid uterus may also exert a compressive affect on the inferior vena cava when the patient is supine, leading to hypotension due to a decreased pre-load. Cardiac output can in this situation be increased by as much as 25% simply by displacing the uterus off the vena cava. Lastly, pregnancy is a hyper-coagulable state, as there is an increase in the production of clotting factors. This should be kept in mind, since the orthopaedic patient is likely to require some period of post-operative immobilization. The increased risk of deep venous thrombosis should accordingly be anticipated.
Niall P Mcgoldrick Connor Green Neil Burke Christine Quinlan Damian Mccormack
Abstract Pregnancy presents unique challenges to both the Orthopaedic surgeon, and the patient. Uniquely there exists not one, but two patients necessitating consideration in each decision process. Physiological changes serve to contribute to the presentation of a number of orthopaedic conditions unique to pregnancy, as well as impacting upon the management of trauma involving the pregnant patient. While elective orthopaedic procedures can generally be postponed until after delivery, trauma usually demands more urgent intervention. A planned and reasoned approach to managing such trauma scenarios is beneficial. In this review article we firstly discuss some of the physiological changes in pregnancy that make the patient susceptible to orthopaedic disease or injury. Secondly, we look at the management of orthopaedic trauma in the pregnant patient. An overview of some of the orthopaedic conditions encountered during pregnancy is presented.
Keywords management principles; orthopaedic conditions; physiological changes; pregnancy; trauma
Trauma management Physiologic change in pregnancy
Trauma has been shown to complicate up to 8% of all pregnancies.6 It is recognized as a leading cause of non-obstetric maternal death.7 The commonest causes of blunt trauma to the pregnant woman include falls, road traffic accidents and assault.
The human body undergoes significant physiological change in preparing for, and adapting to, the pregnant state. The expanding
Niall P Mcgoldrick MB BCh BAO Orthopaedic Senior House Officer, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none.
General principles Initial management: the initial primary survey of a trauma patient should not be altered by pregnancy. The patient should be managed using standard Advanced Trauma Life Support algorithms, beginning with assessments of airway, breathing, and circulation. A b-hCG level should be checked in all females of child-bearing age. In advanced pregnancy a cardiotocograph may be attached to monitor foetal heart rate. Given the haemodynamic changes highlighted earlier, caution must be used in evaluating vital signs. Compensatory changes, that minimize changes to the maternal pulse and blood pressure, may be at the expense of the foetus. Priority should be given to adequately and aggressively resuscitating the mother and stabilizing maternal vital signs.1 This follows, since in most circumstances maternal instability can have potentially catastrophic consequences for foetal outcome. The patient can be positioned on a backboard with a 15 tilt to relieve vena caval compression (see Figure 1). Following appropriate resuscitation of the pregnant patient, a focused secondary survey can now be done.
Connor Green MCh MRCSI Orthopaedic Specialist Registrar, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none. Neil Burke MCh MRCSI Orthopaedic Specialist Registrar, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none. Christine Quinlan MB BCh MRCSI Surgical Senior House Officer, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none. Damian Mccormack MCh FRCS(Orth) Consultant Orthopaedic & Spine Surgeon, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none.
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GENERAL ORTHOPAEDICS
cells rapidly divide and are more radiosensitive. The critical period for central nervous system damage is at 8e15 weeks’ gestation.10 Organogenesis principally occurs during weeks 3e8. The foetus is particularly vulnerable to radiation during this period, and malformation is more likely. The maximum safe dose of radiation appears to be 5 rad (50 mGy).11 At exposures higher than 50 rad, growth retardation and microcephaly have been observed.12 Ten rad doses do not increase risk of foetal death, malformation, or impaired mental development.13 Reassuringly, the typical doses used in diagnostic radiographs are usually far lower than the 5 rad threshold. Dose exposure can be further minimized through use of lead apron protection of the abdomen (where appropriate), and collimation of the beam. This would imply that, when indicated, routine radiological investigation could safely be carried out on the pregnant patient in the out-patient’s orthopaedic clinic, provided a cumulative dose greater than 5 rad is not reached. Computed Tomography (CT) has proven to be a very useful modality. Exposure from CT is dependent on slice depth and number of slices taken. The radiation exposure from CT is far higher than plain film imaging. Typical exposures from CT scan approximate 1.5 rad. Magnetic Resonance Imaging (MRI) can safely be used since it does not use ionizing radiation, and thus is not associated with foetal risk. It is particularly useful and warranted in evaluation of the spine. As noted, in life-threatening situations there should be no hesitation in performing appropriate radiological investigations. The foetal radiation exposures resulting from some of the more common orthopaedic radiological investigations are set out below:
Figure 1 Lateral displacement of the uterus to decompress the inferior vena cava. Taken from Pearlman MD, Tintinalli JE, Dyne PL (eds.) Obstetric and Gynecologic Emergencies: Diagnosis and Management, McGraw-Hill 2004.
Antibiotics: the rationale for the use of antibiotics in the management of open fractures has been long established.8 Choice of the appropriate antibiotic in the pregnant patient is limited however by safety of the drug in terms of potential teratogenesis and effect on foetal development. Teratogenesis occurs during the first trimester. The foetus is most vulnerable during the 3rd to 11th weeks. Administration of drugs during the second and third trimesters may affect growth or functional development. The Food and Drug Administration (FDA) classify drugs based on foetal risk. Category A drugs are safe in pregnancy. There are unfortunately no Category A antibiotics. Category B drugs are felt to be relatively safe. Category C drugs may pose a foetal risk, thus benefit of the drug should be weighed against risk given the circumstances. Open fractures should be treated with a first or second line cephalosporin, such as cefuroxime, or a penicillin. An aminoglycoside may be added in the setting of gross contamination. Vancomycin, a Category B drug, is warranted in MRSA infection. The cephalosporins and penicillin families are considered Category B drugs.9 Gentamicin is a Category C drug.
Rad
No. to reach cumulative 5 rad exposure
Cervical Spine Chest (AP & Lat) Pelvis Hip CT Head CT Chest CT Abdomen CT Lumbar Spine
0.002 0.00007 0.04 0.213 <0.05 <0.100 2.600 3.500
2500 71 429 125 23 >100 >50 1 1
Adapted from Flik K, Kloen P, Toro JB et al. Orthopaedic Trauma in the Pregnant Patient. J Am Acad Orthop Surg 2006; 14: 175e182.
Radiation: adequate work-up of trauma cases necessitates timely radiological evaluation to assess for injury. This should, as a minimum, include plain film imaging of the cervical spine (lateral view), and antero-posterior views of chest and pelvis unless trauma CT imaging is carried out. Little thought is usually given to performing these investigations in the non-pregnant patient but may provoke apprehension in pregnancy because of radiation exposure to the foetus. As a general principle, in lifethreatening situations, there should be no hesitation in performing the appropriate radiological investigation. The effect of high dose radiation on the developing foetus has been well described. Indeed, radiation exposure to the foetus is more of a concern than maternal exposure. This is because foetal
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Radiographic study
Thromboprophylaxis: pregnancy is a hyper-coagulable state. There is increased risk of thrombosis in pregnancy. When the management of trauma leads to immobilization, thromboprophylaxis is indicated. Low-molecular weight heparins should be given in prophylactic doses. There is no role for warfarin, since it is known to cross the placenta and poses a risk to the foetus. It is considered a Category D drug. Alongside pharmacological thromboprophylaxis, compression stockings should be employed to reduce overall risk of thrombosis.
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cases.22 On this basis, conservative management is usually appropriate in the pregnant patient. Nevertheless, treatment decisions should be guided by the severity of symptoms. Conservative options include lifestyle modifications, splinting and oral corticosteroid. Local steroid injection may be beneficial in the case of refractory symptoms. Lifestyle modification can include avoiding repetitive stress to the wrists, the use of ergonomic equipment and taking breaks from manual activities.23 Job modification may be necessary. Splinting with a light, soft splint in a neutral position, or in slight dorsiflexion, has been shown to be beneficial.24 Surgery can usually be deferred until after pregnancy and the decision to operate is revisited in the light of progress after delivery. Symptoms of carpal tunnel syndrome may recur in subsequent pregnancies.1
Tetanus: tetanus prophylaxis poses no known risk to mother or foetus. It should be administered as indicated just as it is administered in the non-pregnant patient. Positioning: as highlighted earlier, the gravid uterus may cause compression of the inferior cava when the patient is in the supine position. The haemodynamic effect of this can be overcome by use of a right hip wedge, lateral displacement of the uterus or, when appropriate, positioning the patient in the lateral decubitus position. Foetal heart monitoring: the need to monitor the foetal heart peri-operatively is guided by gestational age. There is no indication for foetal heart monitoring before 20 weeks gestation. Monitoring between 20 and 23 weeks is controversial. Beyond 23 weeks gestation, foetal heart monitoring is required to assess the foetus, which may necessitate obstetric intervention. Where foetal monitoring is commenced, it is recommended to continue for between 30 min and 48 h following trauma.14,15
Ulnar nerve entrapment: while there has been much published on median nerve entrapment during pregnancy, there exist fewer reports on ulnar neuropathy. Nevertheless, pregnancy has been recognized as risk factor for developing ulnar nerve entrapment. McLennan et al, in a study of 1216 pregnancies, report an incidence of 12% for ulnar neuropathy during pregnancy.25 It is understood that fluid retention during pregnancy is the most likely cause of entrapment. Symptoms typically occur during the third trimester, and usually settle soon after delivery.
Pelvic trauma Pelvic injury during pregnancy can be associated with both maternal and foetal mortality. Leggon et al report a maternal fatality rate of 9%, and a foetal mortality of 35% following pelvic and acetabular trauma.16 In this same study the mechanisms of injury were reported as motor vehicle accident (73%), automobile-pedestrian collision (13%) and falls (14%). Surgical intervention for acetabular and pelvic fractures during pregnancy has been reported in only a few cases in the literature.16 Indeed, the management of pelvic trauma has focused on resuscitative measures initially, and urgent surgery for associated injuries. Management options reported specifically for pelvic injury during pregnancy include bed rest, traction and pelvic sling, external fixation, and open reduction and internal fixation.16 Surgical fixation should be performed within 3 weeks of injury in order to optimize the quality of reduction and fixation.17 Successful vaginal delivery is possible after pelvic fracture.18
Meralgia paraesthetica: there are several reports of women presenting with anterior thigh pain during pregnancy. Indeed the term “meralgia paraesthetica”, coined by Roth in 1895, is derived from the Greek words “meros” (thigh) and “algos” (pain). The condition was first described by Bernhardt in 1878, and presents as pain in the distribution of the lateral femoral cutaneous nerve of the thigh.26 The nerve is derived from the posterior roots of L2 and L3, and courses over iliacus, before emerging just medial to the anterior superior iliac spine (ASIS), and just behind the inguinal ligament. From here it enters the thigh to supply cutaneous sensation to the antero-lateral thigh. Five distinct anatomical variations of the nerve’s passage into the thigh have been identified.27 In pregnancy, it is thought that the nerve becomes entrapped as it passes the ASIS.28 This is likely a compression effect of the gravid uterus, which leads to increased intraabdominal pressure. Symptoms, which can occur at any time during pregnancy, include numbness, paraesthesia and pain in the antero-lateral thigh.28 While most presentations are unilateral, in 20% of cases there may be bilateral involvement.29 Symptoms only occur while erect or supine.30 The condition is diagnosed clinically by careful history and focused neurological examination. Van Diver & Camann note however that the unfamiliar physician may miss the diagnosis leading to unnecessary and often expensive investigations.28 Nerve conduction studies may be a useful adjunctive tool. The differential diagnosis is broad and thus red-flags such as tumour and lumbar disc herniation must be ruled out. Treatment is conservative. The patient should be reassured that in the majority of cases (85%) symptoms will resolve within 4e6 months of presentation.31 Pain can be controlled by simple measures, such as avoiding prolonged periods of standing, eliminating tight clothing, and simple oral analgesia.
Common orthopaedic conditions in pregnancy Nerve entrapment syndromes Carpal tunnel syndrome: carpal tunnel syndrome is a common condition encountered in pregnancy, and is the most common mononeuropathy of pregnancy.1 Its incidence in pregnancy has been variously reported in the literature, ranging widely from 2%19 to 60%.20 It has been noted that this discrepancy may well relate to study design and method of diagnosis.21 It typically presents as numbness or tingling in the thumb, index, and middle fingers and along the radial aspect of the ring finger. Other symptoms include wrist pain, usually worse at night, and loss of grip strength. It may affect the hands bilaterally. The natural history of the condition is not well established. The syndrome most likely relates to retention of fluid in the enclosed compartment of the carpal tunnel.1 The diagnosis is made in the usual manner, based on history and clinical examination. Nerve conduction studies and electromyography may be employed to confirm the diagnosis. Symptoms will almost always resolve after delivery. In one study, symptoms had resolved 2 weeks post-partum in 95% of
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osteoporotic changes in the hip on plain radiographs.35 No underlying cause was found for these radiological findings, and the changes were observed to resolve eventually. This rare disorder was given the name transient osteoporosis of the hip by Hunder and Kelly.36 It is a condition of unknown aetiology, principally affecting women in the third trimester of pregnancy, and middle-aged men. More recently, cases of transient osteoporosis of the hip have been reported in non-pregnant women.37e39 The disorder is characterized clinically by a limited range of motion at the hip associated with pain and an antalgic gait. Radiologically there is marked osteoporotic change in one, or both femoral heads without loss of joint space.40,41 Pain, usually on weight-bearing, may be sudden or gradual in onset and is often progressive.1 Age of presentation ranges from 24 to 75 and although the hip is most commonly affected, it may also involve the knees, feet and ankles.42 Bone marrow oedema and increased bone turnover is exhibited in the affected bone. Lequesne and Mauger describe three distinct phases of the pathological course: firstly the progressive onset of pain preceding radiographic evidence, a second phase of symptom exacerbation and typical radiographic features, and lastly resolution of symptoms and reversal of the radiographic changes.43 Magnetic resonance imaging is the modality of choice for diagnosis since changes such as bone marrow oedema may be identified as early as 48 h from onset of symptoms. A decreased signal intensity on T1-weighted images and an increased signal intensity on T2-weighted images are characteristic (see Figure 2).41,44 Changes on plain radiography may lag behind by 4e6 weeks. The main differential diagnoses include osteonecrosis and septic arthritis. The course of the condition is typically benign, with resolution of symptoms within 6e8 months being the usual outcome, though symptoms may persist for longer. Serious long-term
Dureja and colleagues report on the use of local anaesthetic block for pain relief.31 The diagnosis was confirmed with local infiltration of 0.25% bupivacaine. The patient then subsequently underwent a regimen of repeated blocks on alternate days using divided doses of methylprednisolone 20e120 mg. Diphenylhydantoin was also employed. Ilioinguinal nerve: entrapment of the ilioinguinal nerve may occur during pregnancy. Again, it is thought that neuropathy is a compressive effect of the expanding gravid uterus. The nerve arises from the nerve roots of T12 and L1. It follows a course analogous to the intercostal nerves. The nerve supplies sensation to the skin over the pubic symphysis, superomedial aspect of the femoral triangle and the skin at the base of the labia and inner thighs. Entrapment may occur as the nerve enters the internal oblique and transversus abdominis muscles, just infero-medial to the anterior superior iliac spine.32 Knockaert and colleagues comment that the condition is characterized by the presence of a triad of findings: pain, altered sensation, and the presence of a trigger point.32 Pain is reported in the distribution of the nerve, as described above. Altered sensation may be hyper-, hypo- or dysaesthesia. The trigger point is found infero-medial to the anterior superior iliac spine.32 Extension of the hip exaggerates symptoms. Diagnosis may be facilitated by injection of local anaesthetic in order to distinguish ilioinguinal neuropathy from entrapment of nearby nerves including the genitofemoral and iliohypogastric nerves. Symptoms resolve following delivery. Iliohypogastric nerve: arising primarily from the L1 nerve root, with some contributory fibres from T12, the iliohypogastric nerve supplies cutaneous sensation to the upper buttocks, groin and symphysis pubis.33 While injury to the nerve typically occurs during surgical dissection, direct trauma, or neuroma, pregnancy has been identified as a cause of neuropathy. Pain in the inguinal or suprapubic region is typical. Altered sensation may also be reported. Obturator nerve: entrapment of the obturator nerve may present as ‘hip pain’ in the pregnant patient. The nerve arises from the nerve roots of L2, L3 and L4. The nerve bifurcates into an anterior and a posterior branch anterior to the internal obturator muscle. The gracilis, adductor longus and adductor brevis muscles derive their motor innervation from this nerve. It also forms a cutaneous sensory plexus with the saphenous and femoral nerves. Childbirth and pelvic trauma, along with osteitis pubis and even exercise have been identified as potential causes of entrapment of the nerve.34 Typically, the patient reports pain, hypo- or paraesthesia in the medial thigh, groin or pubic region. The patient may walk with a circumducting gait. There may also be evidence of weakness or wasting of the adductor muscles, and weakness in adduction and internal rotation of the hip.34 Management is generally conservative. Simple analgesia may provide some relief. Alternatively, injection of local anaesthetic or steroid may be both diagnostic and therapeutic.
Figure 2 High signal intensity in left hip on T2-weighted MRI suggestive of extensive bone marrow oedema. A small joint effusion is also seen (arrow). Taken from Guerra JJ, Steinberg ME. Distinguishing transient osteoporosis from avascular necrosis of the hip. J Bone Joint Surg Am, 1995; 77-A: 616e624.
Transient osteoporosis of the hip In 1959 Curtiss and Kincaid reported three patients presenting with pain in the thigh on weight-bearing that was associated with
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problems and fractures are considered rare. Treatment should generally centre on conservative options. Treatment is symptomatic and typically involves the use of simple analgesia, rest and protected weight-bearing. The latter is most important in preventing pathological fracture.45 More recently, the potential benefits of bisphosphonates46 and anti-resorption drugs such as calcitonin47 have been reported, though further evidence is required to fully evaluate these options. Osteonecrosis of the femoral head Since the first description by Pfeifer in 1957 a small number of cases of osteonecrosis of the femoral head associated with pregnancy has been reported in the literature.48 The diagnosis is often delayed or even missed, as it can be mistaken for transient osteoporosis of the hip. The importance of the distinction cannot be over-emphasized. While transient osteoporosis is generally a self-limiting condition responding to conservative, symptomatic treatment, osteonecrosis is progressive and can ultimately lead to femoral head collapse and the need for total hip arthroplasty. Timely recognition of the true diagnosis is therefore necessary. Osteonecrosis is thought to occur typically in older primigravid women with a small body frame who gain a relatively large amount of weight during pregnancy.49 The pregnant woman will typically present with symptoms of hip pain radiating deeply into the groin and down the thigh. The hip becomes symptomatic in the late second, or third trimester of pregnancy. Plain film imaging may reveal sclerosis, the so-called “crescent sign” of subchondral radiolucency, or indeed femoral head collapse (see Figure 3). Bone scan shows increased uptake in the affected femoral head.50 Magnetic Resonance Imaging (MRI) remains the modality of choice for diagnosis however. Findings include decreased signal intensity on both T1-weighted and T2weighted images, and a double-density signal around the lesion. These lesions are often seen in the antero-lateral aspect of the femoral head. These MRI findings distinguish the condition from those seen in transient osteoporosis of the hip. The diagnosis can be obscure however. The precise aetiology has yet to be determined. Montella et al have suggested that the underlying cause is most likely multifactorial, converging on a common final pathway leading to disruption of the femoral head circulation.49 A number of causes have been suggested. One theory focuses on venous congestion and hypercoagulability as a possible cause of vascular interruption. Pregnancy is a hyper-coagulable state. It is thought that this hypercoagulability may give rise to embolic or thrombotic events that lead to vascular occlusion or venous congestion, and subsequent ischaemia of the femoral head. It has been noted that the prevalence of thrombotic events is higher in the third trimester, which corresponds approximately with the typical time of presentation of osteonecrosis.49 Moreover, venous thrombosis is more common on the left side than the right.51 This is generally attributed to a compressive effect of the right common iliac artery crossing over the left common iliac vein, thus impeding drainage.52 In one series of 13 patients (17 hips), all patients had involvement of the left hip, which may have been linked to this anatomical consideration.49 Other theories put forward to explain osteonecrosis consider cortisol levels, and hormones such as
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Figure 3 The crescent sign (arrows) seen on plain film imaging of the left hip (frog leg view). Taken from Stevens K, Tao C, Lee SU et al. Subchondral fractures in osteonecrosis of the femoral head: comparison of radiography, CT, and MR Imaging. Am J Roentgenol, 2003; 180(2): 363e368.
progesterone and oestrogens. The general consensus appears to be that these several causes all contribute to a common outcome, namely a temporary or permanent loss of blood supply to the femoral head. A number of treatment options have been described in the literature. These include: core decompression,53 osteotomy,54 electrical-stimulation55 and both non-vascularized and vascularized structural grafts, often from the fibula.56 There remains much debate as to the optimum approach to treatment. Pubic symphysis dysfunction Disruption of the pubic symphysis has long been recognized as a complication of childbirth.57 Its incidence has been variously reported in the literature to be somewhere between 1 in 3000 to 1 in 30 000 pregnancies.58,59 Snow et al report an incidence as low as 1 in 569 in one institution.60 Maternal uterine contraction force and joint laxity likely contribute to developing the condition. Joint laxity may account for separation of the pubic symphysis by up to 1 cm. This usually causes no pain.61 Separation of the symphysis pubis by more than 1 cm may be considered pathological. It typically occurs during delivery and is associated with factors such as multiparity, prior history of pelvic trauma, forceful uterine contractions and foetal macrosomia.62 The head of the foetus may exert a wedging force, leading to separation. Malpresentation of the foetus is also likely to be a risk factor. The patient usually complains of the sudden onset of pain in the region of the pubic symphysis. The pain may radiate to the back and down the thighs. An audible crack may be heard in some cases.1 The pain may be exacerbated by activities such as walking or standing up. A palpable gap over the pubic
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symphysis is found on examination. Patients usually walk with a waddling gait. Plain radiography of the pelvis confirms the diagnosis. Management is conservative. Bed rest following delivery is generally recommended. Heckman suggests the lateral decubitus position and the use of a pelvic binder to maintain reduction.1 Mobilization is possible once the patient is comfortable. Further pregnancy is reportedly unaffected following pubic symphysis disruption.63
Typically, the patient will describe unilateral radicular pain. They may also report paraesthesiae in a dermatomal distribution. Straight leg raise should elicit symptoms, and a formal neurological examination may reveal weakness and/or altered sensation. Red-flag symptoms for evolving cauda equina syndrome should be sought early. Han and colleagues recommend Magnetic Resonance Imaging as the primary and safest radiological investigation for spinal pathology during pregnancy.69 In general, conservative therapy for the duration of gestation is sufficient for the management of symptoms. Bed rest, physiotherapy for core muscle strengthening and simple analgesia are recommended. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are to be avoided due to concern for teratogenesis. The indications for surgical intervention in pregnant and nonpregnant women are the same.69 Cauda equina represents the only absolute surgical indication in the context of disc prolapse in pregnancy. Relative indications include unbearable pain (beyond conservative control), and progressive weakness. While recent authors have reported successful endoscopic discectomy, the more traditional approach is laminectomy or (micro)discectomy.69 Positioning of the patient on the table may have to be adapted due to gestation. Prone positioning of the pregnant patient is safe during the first and early second trimesters. However, Vougioukas and colleagues recommend the left lateral decubitus position in the late second and third trimesters in order to avoid compression of the vena cava.73
Low back pain One of the more frequent symptoms encountered during pregnancy is low back pain. It has been reported to affect as many as 70% of women during pregnancy.1 Some authors consider it to be an almost inevitable symptom of pregnancy. A number of risk factors have been identified for developing back pain during pregnancy. A history of back pain preceding pregnancy makes it more likely that back pain will occur during pregnancy. Moreover, multiparous women appear to be affected by low back pain more often, and for more prolonged periods, than their primiparous counterparts.65 It is thought that the gravid uterus alters the biomechanics about the pelvis, contributing to a number of symptoms, including low back pain. Normally the pelvis rotates about a fulcrum located at approximately the second sacral segment. During pregnancy, the centre of gravity is shifted anterior to the sacrum, increasing forces on the low back and sacroiliac joints. This occurs due to increasing lumbar lordosis along with relaxation of the sacroiliac ligaments (which ordinarily prevent this forward rotation).66 Typically, the patient presents with a history of pain in the lumbar or sacral regions. Pelvic pain may be reported. The pain is generally not very severe. While pain may move across the buttocks, typical radicular pain is not usually described. Activity often aggravates symptoms. On examination, the paraspinal musculature may be found to be in spasm. FABER (flexion abduction external rotation) or Patrick’s test is useful in detecting pain in the sacroiliac joint. Ritchie also reports that pressing the iliac crests together anteriorly can elicit pain posteriorly in the region of the sacroiliac joints.66 Management is invariably conservative. Regular rest during the day is advisable. Simple analgesia such as paracetamol will generally help with symptomatic relief. Some authors find a trochanteric belt may also be beneficial in helping relieve symptoms.1,67
Cauda equina syndrome While lumbar back pain is a relatively common complaint, the development of cauda equina syndrome during pregnancy is rare.64,68 There exist few case reports in the literature. Indeed it is estimated that only 2% of those who undergo surgery for lumbar disc herniation have cauda equina syndrome.74 Cauda equina syndrome is well recognized as a true orthopaedic emergency and once diagnosis is confirmed, operative intervention at the earliest opportunity should be undertaken in order to avoid permanent neurologic deficit.68 This principle applies irrespective of pregnancy. Indeed, it is well shown that pregnancy at any stage does not represent a contraindication to epidural anaesthesia, general anaesthesia nor surgery. Brown and Levi report successful surgical intervention in three cases of cauda equina syndrome occurring during pregnancy. In their report, the authors found that a Relton-Hall laminectomy frame, or four-poster frame equivalent worked well for pregnant patients. This was because the upper two posts applied pressure to the sternum, while the lower two posts supported the anterior iliac spines and pelvis. This had the effect of relieving pressure from the abdomen and uterus. They further remark that allowing the patient to position herself on the four-poster frame prior to epidural anaesthesia has the added benefit of satisfying both patient and surgeon that there is no undue pressure on the uterus due to the prone position. The pregnant patient who reports so-called red-flag symptoms of cauda equina syndrome should be promptly investigated with Magnetic Resonance Imaging (MRI) of lumbar spine and brought to theatre without delay, as indicated.
Lumbar disc prolapse and radiculopathy Distinguishing lumbar back pain (LBP) from symptomatic lumbar disc prolapse is important since treatment may be radically different. While the latter is considered rare, with an incidence reported to be approximately 1 in 10 000 pregnancies,68 it nevertheless remains the most common spinal pathology requiring intervention during gestation.69 Moreover early recognition of this condition can prevent progressive neurological deficit.70 It has been suggested that pregnancy in itself may not increase the incidence of lumbar disc prolapse.71 However, as the mean age of pregnancy is increasing, the overall prevalence of this condition is also increasing.72
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Summary of principles
17 Em Letournel, Judet R, Elson R. Fractures of the acetabulum. 2nd edn. Berlin; New York: Springer-Verlag, 1993. 18 Vallier HA, Cureton BA, Schubeck D. Pregnancy outcomes after pelvic ring injury. J Orthop Trauma 2012; 26: 302e7. 19 Ekman-Ordeberg G, Salgeback S, Ordeberg G. Carpal tunnel syndrome in pregnancy. A prospective study. Acta Obstet Gynecol Scand 1987; 66: 233e5. 20 Padua L, Aprile I, Caliandro P, et al. Symptoms and neurophysiological picture of carpal tunnel syndrome in pregnancy. Clin Neurophysiol 2001; 112: 1946e51. 21 Padua L, Di Pasquale A, Pazzaglia C, Liotta GA, Librante A, Mondelli M. Systematic review of pregnancy-related carpal tunnel syndrome. Muscle Nerve 2010; 42: 697e702. 22 Wand JS. Carpal tunnel syndrome in pregnancy and lactation. J Hand Surg Br 1990; 15: 93e5. 23 LeBlanc KE, Cestia W. Carpal tunnel syndrome. Am Fam Physician 2011; 83: 952e8. 24 Gravlee JR, Van Durme DJ. Braces and splints for musculoskeletal conditions. Am Fam Physician 2007; 75: 342e8. 25 McLennan HG, Oats JN, Walstab JE. Survey of hand symptoms in pregnancy. Med J Aust 1987; 147: 542e4. 26 Bernhardt M. Neuropathologische Beobachtungen I. periphere Lahmungen. D Arch Klin Med 1878; 22: 362e93. 27 Harney D, Patijn J. Meralgia paresthetica: diagnosis and management strategies. Pain Med 2007; 8: 669e77. 28 Van Diver T, Camann W. Meralgia paresthetica in the parturient. Int J Obstet Anesth 1995; 4: 109e12. 29 Ecker AD, Woltman HW. Meralgia paraesthetica: a report of one hundred and fifty cases. JAMA 1938; 110: 1650e2. 30 Ghent WR. Meralgia paraesthetica. Can Med Assoc J 1959; 81: 631e3. 31 Dureja GP, Gulaya V, Jayalakshmi TS, Mandal P. Management of meralgia paresthetica: a multimodality regimen. Anesth Analg 1995; 80: 1060e1. 32 Knockaert DC, D’Heygere FG, Bobbaers HJ. Ilioinguinal nerve entrapment: a little-known cause of iliac fossa pain. Postgrad Med J 1989; 65: 632e5. 33 Liszka TG, Dellon AL, Manson PN. Iliohypogastric nerve entrapment following abdominoplasty. Plast Reconstr Surg 1994; 93: 181e4. 34 Tipton JS. Obturator neuropathy. Curr Rev Musculoskelet Med 2008; 1: 234e7. 35 Curtiss Jr PH, Kincaid WE. Transitory demineralization of the hip in pregnancy. A report of three cases. J Bone Joint Surg Am 1959; 41-A: 1327e33. 36 Hunder GG, Kelly PJ. Transient osteoporosis of the hip: a clinical syndrome? Arthritis Rheum 1967; 10: 285. 37 Escola A, Pons M, Pasarin A, Majo J. Idiopathic transient osteoporosis of the pelvis in a non-pregnant young woman: a case study. Hip Int 2009; 19: 71e4. 38 Willis-Owen CA, Daurka JS, Chen A, Lewis A. Bilateral femoral neck fractures due to transient osteoporosis of pregnancy: a case report. Cases J 2008; 1: 120. 39 Aynaci O, Kerimoglu S, Ozturk C, Saracoglu M. Bilateral non-traumatic acetabular and femoral neck fractures due to pregnancy-associated osteoporosis. Arch Orthop Trauma Surg 2008; 128: 313e6. 40 Beaulieu JG, Razzano CD, Levine RB. Transient osteoporosis of the hip in pregnancy. Clin Orthop Relat Res 1976; 115: 165e8. 41 Bloem JL. Transient osteoporosis of the hip: MR imaging. Radiology 1988; 167: 753e5.
Pregnancy testing is mandatory in all women of childbearing age who suffer trauma. Initial management is unchanged in both the pregnant and non-pregnant trauma patient e ATLS protocols should be adhered to. Radiation exposure should be minimized where possible. However, where a radiological study is indicated in emergency, there should be no hesitation to proceed with the investigation. Elective procedures should generally be postponed until after delivery. There is no absolute contraindication to surgery during an emergency. Pregnancy-related conditions can generally be treated successfully through conservative management. While back pain is common in pregnancy, red-flag symptoms for cauda equina should be considered and ruled out early to avoid potential neurological deficit. A
REFERENCES 1 Heckman JD, Sassard R. Musculoskeletal considerations in pregnancy. J Bone Joint Surg Am 1994; 76: 1720e30. 2 Marnach ML, Ramin KD, Ramsey PS, Song SW, Stensland JJ, An KN. Characterization of the relationship between joint laxity and maternal hormones in pregnancy. Obstet Gynecol 2003; 101: 331e5. 3 Ostgaard HC, Zetherstrom G, Roos-Hansson E. The posterior pelvic pain provocation test in pregnant women. Eur Spine J 1994; 3: 258e60. 4 Whittaker PG, Macphail S, Lind T. Serial hematologic changes and pregnancy outcome. Obstet Gynecol 1996; 88: 33e9. 5 Van Hook JW. Trauma in pregnancy. Clin Obstet Gynecol 2002; 45: 414e24. 6 D’Amico CJ. Trauma in pregnancy. Top Emerg Med 2002; 24: 26e39. 7 Fildes J, Reed L, Jones N, Martin M, Barrett J. Trauma: the leading cause of maternal death. J Trauma 1992; 32: 643e5. 8 Gustilo RB, Merkow RL, Templeman D. The management of open fractures. J Bone Joint Surg Am 1990; 72: 299e304. 9 Hedstrom S, Martens MG. Antibiotics in pregnancy. Clin Obstet Gynecol 1993; 36: 886e92. 10 Desai P, Suk M. Orthopedic trauma in pregnancy. Am J Orthop (Belle Mead NJ) 2007; 36: E160e6. 11 ACOG Committee Opinion. Number 299, September 2004 (replaces No. 158, September 1995) Guidelines for diagnostic imaging during pregnancy. Obstet Gynecol 2004; 104: 647e51. 12 Brent RL. The effects of embryonic and fetal exposure to x-ray, microwaves, and ultrasound. Clin Perinatol 1986; 13: 615e48. 13 Timins JK. Radiation during pregnancy. N J Med 2001; 98: 29e33. 14 Towery R, English TP, Wisner D. Evaluation of pregnant women after blunt injury. J Trauma 1993; 35: 731e5. Discussion 35e6. 15 Curet MJ, Schermer CR, Demarest GB, Bieneik 3rd EJ, Curet LB. Predictors of outcome in trauma during pregnancy: identification of patients who can be monitored for less than 6 hours. J Trauma 2000; 49: 18e24. Discussion 24e5. 16 Leggon RE, Wood GC, Indeck MC. Pelvic fractures in pregnancy: factors influencing maternal and fetal outcomes. J Trauma 2002; 53: 796e804.
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42 Rocchietti March M, Tovaglia V, Meo A, Pisani D, Tovaglia P, Aliberti G. Transient osteoporosis of the hip. Hip Int 2010; 20: 297e300. 43 Lequesne M, Mauger B. [100 decalcifying algodystrophies of the hip in 74 patients]. Rev Rhum Mal Osteoartic 1982; 49: 787e92. 44 Takatori Y, Kokubo T, Ninomiya S, Nakamura T, Okutsu I, Kamogawa M. Transient osteoporosis of the hip. Magnetic resonance imaging. Clin Orthop Relat Res 1991; 271: 190e4. 45 Balakrishnan A, Schemitsch EH, Pearce D, McKee MD. Distinguishing transient osteoporosis of the hip from avascular necrosis. Can J Surg 2003; 46: 187e92. 46 La Montagna G, Malesci D, Tirri R, Valentini G. Successful neridronate therapy in transient osteoporosis of the hip. Clin Rheumatol 2005; 24: 67e9. 47 Arayssi TK, Tawbi HA, Usta IM, Hourani MH. Calcitonin in the treatment of transient osteoporosis of the hip. Semin Arthritis Rheum 2003; 32: 388e97. 48 Pfeifer W. [A case of unusual form and origin of bilateral symmetrical osteonecrosis of the femoral & humerus heads]. Fortschr Geb Rontgenstr Nuklearmed 1957; 86: 346e9. 49 Montella BJ, Nunley JA, Urbaniak JR. Osteonecrosis of the femoral head associated with pregnancy. A preliminary report. J Bone Joint Surg Am 1999; 81: 790e8. 50 Guerra JJ, Steinberg ME. Distinguishing transient osteoporosis from avascular necrosis of the hip. J Bone Joint Surg Am 1995; 77: 616e24. 51 Ginsberg JS, Brill-Edwards P, Burrows RF, et al. Venous thrombosis during pregnancy: leg and trimester of presentation. Thromb Haemost 1992; 67: 519e20. 52 Cockett FB, Thomas ML. The iliac compression syndrome. Br J Surg 1965; 52: 816e21. 53 Fairbank AC, Bhatia D, Jinnah RH, Hungerford DS. Long-term results of core decompression for ischaemic necrosis of the femoral head. J Bone Joint Surg Br 1995; 77: 42e9. 54 Scher MA, Jakim I. Intertrochanteric osteotomy and autogenous bone-grafting for avascular necrosis of the femoral head. J Bone Joint Surg Am 1993; 75: 1119e33. 55 Steinberg ME, Brighton CT, Hayken GD, Tooze SE, Steinberg DR. Early results in the treatment of avascular necrosis of the femoral head with electrical stimulation. Orthop Clin North Am 1984; 15: 163e75. 56 Urbaniak JR, Coogan PG, Gunneson EB, Nunley JA. Treatment of osteonecrosis of the femoral head with free vascularized fibular grafting. A long-term follow-up study of one hundred and three hips. J Bone Joint Surg Am 1995; 77: 681e94. 57 Callahan JT. Separation of the symphysis pubis. Am J Obstet Gynecol 1953; 66: 281e93.
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58 Luger EJ, Arbel R, Dekel S. Traumatic separation of the symphysis pubis during pregnancy: a case report. J Trauma 1995; 38: 255e6. 59 Kane R, Erez S, O’Leary JA. Symptomatic symphyseal separation in pregnancy. Surg Gynecol Obstet 1967; 124: 1032e6. 60 Snow RE, Neubert AG. Peripartum pubic symphysis separation: a case series and review of the literature. Obstet Gynecol Surv 1997; 52: 438e43. 61 Young J. Relaxation of the pelvic joints in pregnancy: pelvic arthropathy of pregnancy. J Obstet Gynec Br Empire 1940; 47: 493. 62 Smith MW, Marcus PS, Wurtz LD. Orthopedic issues in pregnancy. Obstet Gynecol Surv 2008; 63: 103e11. 63 Dhar S, Anderton JM. Rupture of the symphysis pubis during labor. Clin Orthop Relat Res 1992; 283: 252e7. 64 Fast A, Shapiro D, Ducommun EJ, Friedmann LW, Bouklas T, Floman Y. Low-back pain in pregnancy. Spine (Phila Pa 1976) 1987; 12: 368e71. 65 Ostgaard HC, Andersson GB. Previous back pain and risk of developing back pain in a future pregnancy. Spine (Phila Pa 1976) 1991; 16: 432e6. 66 Ritchie JR. Orthopedic considerations during pregnancy. Clin Obstet Gynecol 2003; 46: 456e66. 67 Heckman JD. Managing musculoskeletal problems in pregnant patients. J Musculoskel Med 1984; 1: 35e40. 68 LaBan MM, Perrin JC, Latimer FR. Pregnancy and the herniated lumbar disc. Arch Phys Med Rehabil 1983; 64: 319e21. 69 Han IH, Kuh SU, Kim JH, et al. Clinical approach and surgical strategy for spinal diseases in pregnant women: a report of ten cases. Spine (Phila Pa 1976) 2008; 33: E614e9. 70 Garmel SH, Guzelian GA, D’Alton JG, D’Alton ME. Lumbar disk disease in pregnancy. Obstet Gynecol 1997; 89: 821e2. 71 Weinreb JC, Wolbarsht LB, Cohen JM, Brown CE, Maravilla KR. Prevalence of lumbosacral intervertebral disk abnormalities on MR images in pregnant and asymptomatic nonpregnant women. Radiology 1989; 170: 125e8. 72 Parrish KM, Holt VL, Easterling TR, Connell FA, LoGerfo JP. Effect of changes in maternal age, parity, and birth weight distribution on primary cesarean delivery rates. JAMA 1994; 271: 443e7. 73 Vougioukas VI, Kyroussis G, Glasker S, Tatagiba M, Scheufler KM. Neurosurgical interventions during pregnancy and the puerperium: clinical considerations and management. Acta Neurochir (Wien) 2004; 146: 1287e91. Discussion 91e92. 74 O’Laoire SA, Crockard HA, Thomas DG. Prognosis for sphincter recovery after operation for cauda equina compression owing to lumbar disc prolapse. Br Med J (Clin Res Ed) 1981; 282: 1852e4.
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Pregnancy and the orthopaedic patient
uterus and its contents alters the body’s centre of gravity, moving it anteriorly. This applies mechanical stress upon the axial skeleton, particularly in the lumbar spine. Heckman et al report that 70% of women experience low back pain at some point during pregnancy.1 Hormones such as relaxin, released during pregnancy, have in the past been theorized to affect joint laxity. Recent evidence suggests relaxin may not be responsible for this joint laxity, however.2 Irrespective of the precise mechanism involved, joint laxity is common in pregnancy. It begins from the 10th week of gestation and may last for up to 4e12 weeks postpartum.3 Furthermore, a number of haemodynamic changes occur that requires careful consideration in the orthopaedic trauma situation. Cardiac output increases by 35e50% over the first 10 weeks of gestation. This increase is maintained throughout the pregnancy. Circulating maternal blood volume also increases by 40e50%. A dilutional anaemia exists, since red blood cell mass does not increase to the same extent as this increase in plasma volume. A small decrease in haematocrit is observed.4 These changes may serve to mask the true extent of blood loss in the trauma setting. Blood loss of up to 2 L may therefore not be immediately apparent, since the mean arterial pressure remains stable.5 The gravid uterus may also exert a compressive affect on the inferior vena cava when the patient is supine, leading to hypotension due to a decreased pre-load. Cardiac output can in this situation be increased by as much as 25% simply by displacing the uterus off the vena cava. Lastly, pregnancy is a hyper-coagulable state, as there is an increase in the production of clotting factors. This should be kept in mind, since the orthopaedic patient is likely to require some period of post-operative immobilization. The increased risk of deep venous thrombosis should accordingly be anticipated.
Niall P Mcgoldrick Connor Green Neil Burke Christine Quinlan Damian Mccormack
Abstract Pregnancy presents unique challenges to both the Orthopaedic surgeon, and the patient. Uniquely there exists not one, but two patients necessitating consideration in each decision process. Physiological changes serve to contribute to the presentation of a number of orthopaedic conditions unique to pregnancy, as well as impacting upon the management of trauma involving the pregnant patient. While elective orthopaedic procedures can generally be postponed until after delivery, trauma usually demands more urgent intervention. A planned and reasoned approach to managing such trauma scenarios is beneficial. In this review article we firstly discuss some of the physiological changes in pregnancy that make the patient susceptible to orthopaedic disease or injury. Secondly, we look at the management of orthopaedic trauma in the pregnant patient. An overview of some of the orthopaedic conditions encountered during pregnancy is presented.
Keywords management principles; orthopaedic conditions; physiological changes; pregnancy; trauma
Trauma management Physiologic change in pregnancy
Trauma has been shown to complicate up to 8% of all pregnancies.6 It is recognized as a leading cause of non-obstetric maternal death.7 The commonest causes of blunt trauma to the pregnant woman include falls, road traffic accidents and assault.
The human body undergoes significant physiological change in preparing for, and adapting to, the pregnant state. The expanding
Niall P Mcgoldrick MB BCh BAO Orthopaedic Senior House Officer, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none.
General principles Initial management: the initial primary survey of a trauma patient should not be altered by pregnancy. The patient should be managed using standard Advanced Trauma Life Support algorithms, beginning with assessments of airway, breathing, and circulation. A b-hCG level should be checked in all females of child-bearing age. In advanced pregnancy a cardiotocograph may be attached to monitor foetal heart rate. Given the haemodynamic changes highlighted earlier, caution must be used in evaluating vital signs. Compensatory changes, that minimize changes to the maternal pulse and blood pressure, may be at the expense of the foetus. Priority should be given to adequately and aggressively resuscitating the mother and stabilizing maternal vital signs.1 This follows, since in most circumstances maternal instability can have potentially catastrophic consequences for foetal outcome. The patient can be positioned on a backboard with a 15 tilt to relieve vena caval compression (see Figure 1). Following appropriate resuscitation of the pregnant patient, a focused secondary survey can now be done.
Connor Green MCh MRCSI Orthopaedic Specialist Registrar, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none. Neil Burke MCh MRCSI Orthopaedic Specialist Registrar, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none. Christine Quinlan MB BCh MRCSI Surgical Senior House Officer, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none. Damian Mccormack MCh FRCS(Orth) Consultant Orthopaedic & Spine Surgeon, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, Dublin, Ireland. Conflicts of interest: none.
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cells rapidly divide and are more radiosensitive. The critical period for central nervous system damage is at 8e15 weeks’ gestation.10 Organogenesis principally occurs during weeks 3e8. The foetus is particularly vulnerable to radiation during this period, and malformation is more likely. The maximum safe dose of radiation appears to be 5 rad (50 mGy).11 At exposures higher than 50 rad, growth retardation and microcephaly have been observed.12 Ten rad doses do not increase risk of foetal death, malformation, or impaired mental development.13 Reassuringly, the typical doses used in diagnostic radiographs are usually far lower than the 5 rad threshold. Dose exposure can be further minimized through use of lead apron protection of the abdomen (where appropriate), and collimation of the beam. This would imply that, when indicated, routine radiological investigation could safely be carried out on the pregnant patient in the out-patient’s orthopaedic clinic, provided a cumulative dose greater than 5 rad is not reached. Computed Tomography (CT) has proven to be a very useful modality. Exposure from CT is dependent on slice depth and number of slices taken. The radiation exposure from CT is far higher than plain film imaging. Typical exposures from CT scan approximate 1.5 rad. Magnetic Resonance Imaging (MRI) can safely be used since it does not use ionizing radiation, and thus is not associated with foetal risk. It is particularly useful and warranted in evaluation of the spine. As noted, in life-threatening situations there should be no hesitation in performing appropriate radiological investigations. The foetal radiation exposures resulting from some of the more common orthopaedic radiological investigations are set out below:
Figure 1 Lateral displacement of the uterus to decompress the inferior vena cava. Taken from Pearlman MD, Tintinalli JE, Dyne PL (eds.) Obstetric and Gynecologic Emergencies: Diagnosis and Management, McGraw-Hill 2004.
Antibiotics: the rationale for the use of antibiotics in the management of open fractures has been long established.8 Choice of the appropriate antibiotic in the pregnant patient is limited however by safety of the drug in terms of potential teratogenesis and effect on foetal development. Teratogenesis occurs during the first trimester. The foetus is most vulnerable during the 3rd to 11th weeks. Administration of drugs during the second and third trimesters may affect growth or functional development. The Food and Drug Administration (FDA) classify drugs based on foetal risk. Category A drugs are safe in pregnancy. There are unfortunately no Category A antibiotics. Category B drugs are felt to be relatively safe. Category C drugs may pose a foetal risk, thus benefit of the drug should be weighed against risk given the circumstances. Open fractures should be treated with a first or second line cephalosporin, such as cefuroxime, or a penicillin. An aminoglycoside may be added in the setting of gross contamination. Vancomycin, a Category B drug, is warranted in MRSA infection. The cephalosporins and penicillin families are considered Category B drugs.9 Gentamicin is a Category C drug.
Rad
No. to reach cumulative 5 rad exposure
Cervical Spine Chest (AP & Lat) Pelvis Hip CT Head CT Chest CT Abdomen CT Lumbar Spine
0.002 0.00007 0.04 0.213 <0.05 <0.100 2.600 3.500
2500 71 429 125 23 >100 >50 1 1
Adapted from Flik K, Kloen P, Toro JB et al. Orthopaedic Trauma in the Pregnant Patient. J Am Acad Orthop Surg 2006; 14: 175e182.
Radiation: adequate work-up of trauma cases necessitates timely radiological evaluation to assess for injury. This should, as a minimum, include plain film imaging of the cervical spine (lateral view), and antero-posterior views of chest and pelvis unless trauma CT imaging is carried out. Little thought is usually given to performing these investigations in the non-pregnant patient but may provoke apprehension in pregnancy because of radiation exposure to the foetus. As a general principle, in lifethreatening situations, there should be no hesitation in performing the appropriate radiological investigation. The effect of high dose radiation on the developing foetus has been well described. Indeed, radiation exposure to the foetus is more of a concern than maternal exposure. This is because foetal
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Radiographic study
Thromboprophylaxis: pregnancy is a hyper-coagulable state. There is increased risk of thrombosis in pregnancy. When the management of trauma leads to immobilization, thromboprophylaxis is indicated. Low-molecular weight heparins should be given in prophylactic doses. There is no role for warfarin, since it is known to cross the placenta and poses a risk to the foetus. It is considered a Category D drug. Alongside pharmacological thromboprophylaxis, compression stockings should be employed to reduce overall risk of thrombosis.
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cases.22 On this basis, conservative management is usually appropriate in the pregnant patient. Nevertheless, treatment decisions should be guided by the severity of symptoms. Conservative options include lifestyle modifications, splinting and oral corticosteroid. Local steroid injection may be beneficial in the case of refractory symptoms. Lifestyle modification can include avoiding repetitive stress to the wrists, the use of ergonomic equipment and taking breaks from manual activities.23 Job modification may be necessary. Splinting with a light, soft splint in a neutral position, or in slight dorsiflexion, has been shown to be beneficial.24 Surgery can usually be deferred until after pregnancy and the decision to operate is revisited in the light of progress after delivery. Symptoms of carpal tunnel syndrome may recur in subsequent pregnancies.1
Tetanus: tetanus prophylaxis poses no known risk to mother or foetus. It should be administered as indicated just as it is administered in the non-pregnant patient. Positioning: as highlighted earlier, the gravid uterus may cause compression of the inferior cava when the patient is in the supine position. The haemodynamic effect of this can be overcome by use of a right hip wedge, lateral displacement of the uterus or, when appropriate, positioning the patient in the lateral decubitus position. Foetal heart monitoring: the need to monitor the foetal heart peri-operatively is guided by gestational age. There is no indication for foetal heart monitoring before 20 weeks gestation. Monitoring between 20 and 23 weeks is controversial. Beyond 23 weeks gestation, foetal heart monitoring is required to assess the foetus, which may necessitate obstetric intervention. Where foetal monitoring is commenced, it is recommended to continue for between 30 min and 48 h following trauma.14,15
Ulnar nerve entrapment: while there has been much published on median nerve entrapment during pregnancy, there exist fewer reports on ulnar neuropathy. Nevertheless, pregnancy has been recognized as risk factor for developing ulnar nerve entrapment. McLennan et al, in a study of 1216 pregnancies, report an incidence of 12% for ulnar neuropathy during pregnancy.25 It is understood that fluid retention during pregnancy is the most likely cause of entrapment. Symptoms typically occur during the third trimester, and usually settle soon after delivery.
Pelvic trauma Pelvic injury during pregnancy can be associated with both maternal and foetal mortality. Leggon et al report a maternal fatality rate of 9%, and a foetal mortality of 35% following pelvic and acetabular trauma.16 In this same study the mechanisms of injury were reported as motor vehicle accident (73%), automobile-pedestrian collision (13%) and falls (14%). Surgical intervention for acetabular and pelvic fractures during pregnancy has been reported in only a few cases in the literature.16 Indeed, the management of pelvic trauma has focused on resuscitative measures initially, and urgent surgery for associated injuries. Management options reported specifically for pelvic injury during pregnancy include bed rest, traction and pelvic sling, external fixation, and open reduction and internal fixation.16 Surgical fixation should be performed within 3 weeks of injury in order to optimize the quality of reduction and fixation.17 Successful vaginal delivery is possible after pelvic fracture.18
Meralgia paraesthetica: there are several reports of women presenting with anterior thigh pain during pregnancy. Indeed the term “meralgia paraesthetica”, coined by Roth in 1895, is derived from the Greek words “meros” (thigh) and “algos” (pain). The condition was first described by Bernhardt in 1878, and presents as pain in the distribution of the lateral femoral cutaneous nerve of the thigh.26 The nerve is derived from the posterior roots of L2 and L3, and courses over iliacus, before emerging just medial to the anterior superior iliac spine (ASIS), and just behind the inguinal ligament. From here it enters the thigh to supply cutaneous sensation to the antero-lateral thigh. Five distinct anatomical variations of the nerve’s passage into the thigh have been identified.27 In pregnancy, it is thought that the nerve becomes entrapped as it passes the ASIS.28 This is likely a compression effect of the gravid uterus, which leads to increased intraabdominal pressure. Symptoms, which can occur at any time during pregnancy, include numbness, paraesthesia and pain in the antero-lateral thigh.28 While most presentations are unilateral, in 20% of cases there may be bilateral involvement.29 Symptoms only occur while erect or supine.30 The condition is diagnosed clinically by careful history and focused neurological examination. Van Diver & Camann note however that the unfamiliar physician may miss the diagnosis leading to unnecessary and often expensive investigations.28 Nerve conduction studies may be a useful adjunctive tool. The differential diagnosis is broad and thus red-flags such as tumour and lumbar disc herniation must be ruled out. Treatment is conservative. The patient should be reassured that in the majority of cases (85%) symptoms will resolve within 4e6 months of presentation.31 Pain can be controlled by simple measures, such as avoiding prolonged periods of standing, eliminating tight clothing, and simple oral analgesia.
Common orthopaedic conditions in pregnancy Nerve entrapment syndromes Carpal tunnel syndrome: carpal tunnel syndrome is a common condition encountered in pregnancy, and is the most common mononeuropathy of pregnancy.1 Its incidence in pregnancy has been variously reported in the literature, ranging widely from 2%19 to 60%.20 It has been noted that this discrepancy may well relate to study design and method of diagnosis.21 It typically presents as numbness or tingling in the thumb, index, and middle fingers and along the radial aspect of the ring finger. Other symptoms include wrist pain, usually worse at night, and loss of grip strength. It may affect the hands bilaterally. The natural history of the condition is not well established. The syndrome most likely relates to retention of fluid in the enclosed compartment of the carpal tunnel.1 The diagnosis is made in the usual manner, based on history and clinical examination. Nerve conduction studies and electromyography may be employed to confirm the diagnosis. Symptoms will almost always resolve after delivery. In one study, symptoms had resolved 2 weeks post-partum in 95% of
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osteoporotic changes in the hip on plain radiographs.35 No underlying cause was found for these radiological findings, and the changes were observed to resolve eventually. This rare disorder was given the name transient osteoporosis of the hip by Hunder and Kelly.36 It is a condition of unknown aetiology, principally affecting women in the third trimester of pregnancy, and middle-aged men. More recently, cases of transient osteoporosis of the hip have been reported in non-pregnant women.37e39 The disorder is characterized clinically by a limited range of motion at the hip associated with pain and an antalgic gait. Radiologically there is marked osteoporotic change in one, or both femoral heads without loss of joint space.40,41 Pain, usually on weight-bearing, may be sudden or gradual in onset and is often progressive.1 Age of presentation ranges from 24 to 75 and although the hip is most commonly affected, it may also involve the knees, feet and ankles.42 Bone marrow oedema and increased bone turnover is exhibited in the affected bone. Lequesne and Mauger describe three distinct phases of the pathological course: firstly the progressive onset of pain preceding radiographic evidence, a second phase of symptom exacerbation and typical radiographic features, and lastly resolution of symptoms and reversal of the radiographic changes.43 Magnetic resonance imaging is the modality of choice for diagnosis since changes such as bone marrow oedema may be identified as early as 48 h from onset of symptoms. A decreased signal intensity on T1-weighted images and an increased signal intensity on T2-weighted images are characteristic (see Figure 2).41,44 Changes on plain radiography may lag behind by 4e6 weeks. The main differential diagnoses include osteonecrosis and septic arthritis. The course of the condition is typically benign, with resolution of symptoms within 6e8 months being the usual outcome, though symptoms may persist for longer. Serious long-term
Dureja and colleagues report on the use of local anaesthetic block for pain relief.31 The diagnosis was confirmed with local infiltration of 0.25% bupivacaine. The patient then subsequently underwent a regimen of repeated blocks on alternate days using divided doses of methylprednisolone 20e120 mg. Diphenylhydantoin was also employed. Ilioinguinal nerve: entrapment of the ilioinguinal nerve may occur during pregnancy. Again, it is thought that neuropathy is a compressive effect of the expanding gravid uterus. The nerve arises from the nerve roots of T12 and L1. It follows a course analogous to the intercostal nerves. The nerve supplies sensation to the skin over the pubic symphysis, superomedial aspect of the femoral triangle and the skin at the base of the labia and inner thighs. Entrapment may occur as the nerve enters the internal oblique and transversus abdominis muscles, just infero-medial to the anterior superior iliac spine.32 Knockaert and colleagues comment that the condition is characterized by the presence of a triad of findings: pain, altered sensation, and the presence of a trigger point.32 Pain is reported in the distribution of the nerve, as described above. Altered sensation may be hyper-, hypo- or dysaesthesia. The trigger point is found infero-medial to the anterior superior iliac spine.32 Extension of the hip exaggerates symptoms. Diagnosis may be facilitated by injection of local anaesthetic in order to distinguish ilioinguinal neuropathy from entrapment of nearby nerves including the genitofemoral and iliohypogastric nerves. Symptoms resolve following delivery. Iliohypogastric nerve: arising primarily from the L1 nerve root, with some contributory fibres from T12, the iliohypogastric nerve supplies cutaneous sensation to the upper buttocks, groin and symphysis pubis.33 While injury to the nerve typically occurs during surgical dissection, direct trauma, or neuroma, pregnancy has been identified as a cause of neuropathy. Pain in the inguinal or suprapubic region is typical. Altered sensation may also be reported. Obturator nerve: entrapment of the obturator nerve may present as ‘hip pain’ in the pregnant patient. The nerve arises from the nerve roots of L2, L3 and L4. The nerve bifurcates into an anterior and a posterior branch anterior to the internal obturator muscle. The gracilis, adductor longus and adductor brevis muscles derive their motor innervation from this nerve. It also forms a cutaneous sensory plexus with the saphenous and femoral nerves. Childbirth and pelvic trauma, along with osteitis pubis and even exercise have been identified as potential causes of entrapment of the nerve.34 Typically, the patient reports pain, hypo- or paraesthesia in the medial thigh, groin or pubic region. The patient may walk with a circumducting gait. There may also be evidence of weakness or wasting of the adductor muscles, and weakness in adduction and internal rotation of the hip.34 Management is generally conservative. Simple analgesia may provide some relief. Alternatively, injection of local anaesthetic or steroid may be both diagnostic and therapeutic.
Figure 2 High signal intensity in left hip on T2-weighted MRI suggestive of extensive bone marrow oedema. A small joint effusion is also seen (arrow). Taken from Guerra JJ, Steinberg ME. Distinguishing transient osteoporosis from avascular necrosis of the hip. J Bone Joint Surg Am, 1995; 77-A: 616e624.
Transient osteoporosis of the hip In 1959 Curtiss and Kincaid reported three patients presenting with pain in the thigh on weight-bearing that was associated with
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problems and fractures are considered rare. Treatment should generally centre on conservative options. Treatment is symptomatic and typically involves the use of simple analgesia, rest and protected weight-bearing. The latter is most important in preventing pathological fracture.45 More recently, the potential benefits of bisphosphonates46 and anti-resorption drugs such as calcitonin47 have been reported, though further evidence is required to fully evaluate these options. Osteonecrosis of the femoral head Since the first description by Pfeifer in 1957 a small number of cases of osteonecrosis of the femoral head associated with pregnancy has been reported in the literature.48 The diagnosis is often delayed or even missed, as it can be mistaken for transient osteoporosis of the hip. The importance of the distinction cannot be over-emphasized. While transient osteoporosis is generally a self-limiting condition responding to conservative, symptomatic treatment, osteonecrosis is progressive and can ultimately lead to femoral head collapse and the need for total hip arthroplasty. Timely recognition of the true diagnosis is therefore necessary. Osteonecrosis is thought to occur typically in older primigravid women with a small body frame who gain a relatively large amount of weight during pregnancy.49 The pregnant woman will typically present with symptoms of hip pain radiating deeply into the groin and down the thigh. The hip becomes symptomatic in the late second, or third trimester of pregnancy. Plain film imaging may reveal sclerosis, the so-called “crescent sign” of subchondral radiolucency, or indeed femoral head collapse (see Figure 3). Bone scan shows increased uptake in the affected femoral head.50 Magnetic Resonance Imaging (MRI) remains the modality of choice for diagnosis however. Findings include decreased signal intensity on both T1-weighted and T2weighted images, and a double-density signal around the lesion. These lesions are often seen in the antero-lateral aspect of the femoral head. These MRI findings distinguish the condition from those seen in transient osteoporosis of the hip. The diagnosis can be obscure however. The precise aetiology has yet to be determined. Montella et al have suggested that the underlying cause is most likely multifactorial, converging on a common final pathway leading to disruption of the femoral head circulation.49 A number of causes have been suggested. One theory focuses on venous congestion and hypercoagulability as a possible cause of vascular interruption. Pregnancy is a hyper-coagulable state. It is thought that this hypercoagulability may give rise to embolic or thrombotic events that lead to vascular occlusion or venous congestion, and subsequent ischaemia of the femoral head. It has been noted that the prevalence of thrombotic events is higher in the third trimester, which corresponds approximately with the typical time of presentation of osteonecrosis.49 Moreover, venous thrombosis is more common on the left side than the right.51 This is generally attributed to a compressive effect of the right common iliac artery crossing over the left common iliac vein, thus impeding drainage.52 In one series of 13 patients (17 hips), all patients had involvement of the left hip, which may have been linked to this anatomical consideration.49 Other theories put forward to explain osteonecrosis consider cortisol levels, and hormones such as
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Figure 3 The crescent sign (arrows) seen on plain film imaging of the left hip (frog leg view). Taken from Stevens K, Tao C, Lee SU et al. Subchondral fractures in osteonecrosis of the femoral head: comparison of radiography, CT, and MR Imaging. Am J Roentgenol, 2003; 180(2): 363e368.
progesterone and oestrogens. The general consensus appears to be that these several causes all contribute to a common outcome, namely a temporary or permanent loss of blood supply to the femoral head. A number of treatment options have been described in the literature. These include: core decompression,53 osteotomy,54 electrical-stimulation55 and both non-vascularized and vascularized structural grafts, often from the fibula.56 There remains much debate as to the optimum approach to treatment. Pubic symphysis dysfunction Disruption of the pubic symphysis has long been recognized as a complication of childbirth.57 Its incidence has been variously reported in the literature to be somewhere between 1 in 3000 to 1 in 30 000 pregnancies.58,59 Snow et al report an incidence as low as 1 in 569 in one institution.60 Maternal uterine contraction force and joint laxity likely contribute to developing the condition. Joint laxity may account for separation of the pubic symphysis by up to 1 cm. This usually causes no pain.61 Separation of the symphysis pubis by more than 1 cm may be considered pathological. It typically occurs during delivery and is associated with factors such as multiparity, prior history of pelvic trauma, forceful uterine contractions and foetal macrosomia.62 The head of the foetus may exert a wedging force, leading to separation. Malpresentation of the foetus is also likely to be a risk factor. The patient usually complains of the sudden onset of pain in the region of the pubic symphysis. The pain may radiate to the back and down the thighs. An audible crack may be heard in some cases.1 The pain may be exacerbated by activities such as walking or standing up. A palpable gap over the pubic
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symphysis is found on examination. Patients usually walk with a waddling gait. Plain radiography of the pelvis confirms the diagnosis. Management is conservative. Bed rest following delivery is generally recommended. Heckman suggests the lateral decubitus position and the use of a pelvic binder to maintain reduction.1 Mobilization is possible once the patient is comfortable. Further pregnancy is reportedly unaffected following pubic symphysis disruption.63
Typically, the patient will describe unilateral radicular pain. They may also report paraesthesiae in a dermatomal distribution. Straight leg raise should elicit symptoms, and a formal neurological examination may reveal weakness and/or altered sensation. Red-flag symptoms for evolving cauda equina syndrome should be sought early. Han and colleagues recommend Magnetic Resonance Imaging as the primary and safest radiological investigation for spinal pathology during pregnancy.69 In general, conservative therapy for the duration of gestation is sufficient for the management of symptoms. Bed rest, physiotherapy for core muscle strengthening and simple analgesia are recommended. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are to be avoided due to concern for teratogenesis. The indications for surgical intervention in pregnant and nonpregnant women are the same.69 Cauda equina represents the only absolute surgical indication in the context of disc prolapse in pregnancy. Relative indications include unbearable pain (beyond conservative control), and progressive weakness. While recent authors have reported successful endoscopic discectomy, the more traditional approach is laminectomy or (micro)discectomy.69 Positioning of the patient on the table may have to be adapted due to gestation. Prone positioning of the pregnant patient is safe during the first and early second trimesters. However, Vougioukas and colleagues recommend the left lateral decubitus position in the late second and third trimesters in order to avoid compression of the vena cava.73
Low back pain One of the more frequent symptoms encountered during pregnancy is low back pain. It has been reported to affect as many as 70% of women during pregnancy.1 Some authors consider it to be an almost inevitable symptom of pregnancy. A number of risk factors have been identified for developing back pain during pregnancy. A history of back pain preceding pregnancy makes it more likely that back pain will occur during pregnancy. Moreover, multiparous women appear to be affected by low back pain more often, and for more prolonged periods, than their primiparous counterparts.65 It is thought that the gravid uterus alters the biomechanics about the pelvis, contributing to a number of symptoms, including low back pain. Normally the pelvis rotates about a fulcrum located at approximately the second sacral segment. During pregnancy, the centre of gravity is shifted anterior to the sacrum, increasing forces on the low back and sacroiliac joints. This occurs due to increasing lumbar lordosis along with relaxation of the sacroiliac ligaments (which ordinarily prevent this forward rotation).66 Typically, the patient presents with a history of pain in the lumbar or sacral regions. Pelvic pain may be reported. The pain is generally not very severe. While pain may move across the buttocks, typical radicular pain is not usually described. Activity often aggravates symptoms. On examination, the paraspinal musculature may be found to be in spasm. FABER (flexion abduction external rotation) or Patrick’s test is useful in detecting pain in the sacroiliac joint. Ritchie also reports that pressing the iliac crests together anteriorly can elicit pain posteriorly in the region of the sacroiliac joints.66 Management is invariably conservative. Regular rest during the day is advisable. Simple analgesia such as paracetamol will generally help with symptomatic relief. Some authors find a trochanteric belt may also be beneficial in helping relieve symptoms.1,67
Cauda equina syndrome While lumbar back pain is a relatively common complaint, the development of cauda equina syndrome during pregnancy is rare.64,68 There exist few case reports in the literature. Indeed it is estimated that only 2% of those who undergo surgery for lumbar disc herniation have cauda equina syndrome.74 Cauda equina syndrome is well recognized as a true orthopaedic emergency and once diagnosis is confirmed, operative intervention at the earliest opportunity should be undertaken in order to avoid permanent neurologic deficit.68 This principle applies irrespective of pregnancy. Indeed, it is well shown that pregnancy at any stage does not represent a contraindication to epidural anaesthesia, general anaesthesia nor surgery. Brown and Levi report successful surgical intervention in three cases of cauda equina syndrome occurring during pregnancy. In their report, the authors found that a Relton-Hall laminectomy frame, or four-poster frame equivalent worked well for pregnant patients. This was because the upper two posts applied pressure to the sternum, while the lower two posts supported the anterior iliac spines and pelvis. This had the effect of relieving pressure from the abdomen and uterus. They further remark that allowing the patient to position herself on the four-poster frame prior to epidural anaesthesia has the added benefit of satisfying both patient and surgeon that there is no undue pressure on the uterus due to the prone position. The pregnant patient who reports so-called red-flag symptoms of cauda equina syndrome should be promptly investigated with Magnetic Resonance Imaging (MRI) of lumbar spine and brought to theatre without delay, as indicated.
Lumbar disc prolapse and radiculopathy Distinguishing lumbar back pain (LBP) from symptomatic lumbar disc prolapse is important since treatment may be radically different. While the latter is considered rare, with an incidence reported to be approximately 1 in 10 000 pregnancies,68 it nevertheless remains the most common spinal pathology requiring intervention during gestation.69 Moreover early recognition of this condition can prevent progressive neurological deficit.70 It has been suggested that pregnancy in itself may not increase the incidence of lumbar disc prolapse.71 However, as the mean age of pregnancy is increasing, the overall prevalence of this condition is also increasing.72
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Summary of principles
17 Em Letournel, Judet R, Elson R. Fractures of the acetabulum. 2nd edn. Berlin; New York: Springer-Verlag, 1993. 18 Vallier HA, Cureton BA, Schubeck D. Pregnancy outcomes after pelvic ring injury. J Orthop Trauma 2012; 26: 302e7. 19 Ekman-Ordeberg G, Salgeback S, Ordeberg G. Carpal tunnel syndrome in pregnancy. A prospective study. Acta Obstet Gynecol Scand 1987; 66: 233e5. 20 Padua L, Aprile I, Caliandro P, et al. Symptoms and neurophysiological picture of carpal tunnel syndrome in pregnancy. Clin Neurophysiol 2001; 112: 1946e51. 21 Padua L, Di Pasquale A, Pazzaglia C, Liotta GA, Librante A, Mondelli M. Systematic review of pregnancy-related carpal tunnel syndrome. Muscle Nerve 2010; 42: 697e702. 22 Wand JS. Carpal tunnel syndrome in pregnancy and lactation. J Hand Surg Br 1990; 15: 93e5. 23 LeBlanc KE, Cestia W. Carpal tunnel syndrome. Am Fam Physician 2011; 83: 952e8. 24 Gravlee JR, Van Durme DJ. Braces and splints for musculoskeletal conditions. Am Fam Physician 2007; 75: 342e8. 25 McLennan HG, Oats JN, Walstab JE. Survey of hand symptoms in pregnancy. Med J Aust 1987; 147: 542e4. 26 Bernhardt M. Neuropathologische Beobachtungen I. periphere Lahmungen. D Arch Klin Med 1878; 22: 362e93. 27 Harney D, Patijn J. Meralgia paresthetica: diagnosis and management strategies. Pain Med 2007; 8: 669e77. 28 Van Diver T, Camann W. Meralgia paresthetica in the parturient. Int J Obstet Anesth 1995; 4: 109e12. 29 Ecker AD, Woltman HW. Meralgia paraesthetica: a report of one hundred and fifty cases. JAMA 1938; 110: 1650e2. 30 Ghent WR. Meralgia paraesthetica. Can Med Assoc J 1959; 81: 631e3. 31 Dureja GP, Gulaya V, Jayalakshmi TS, Mandal P. Management of meralgia paresthetica: a multimodality regimen. Anesth Analg 1995; 80: 1060e1. 32 Knockaert DC, D’Heygere FG, Bobbaers HJ. Ilioinguinal nerve entrapment: a little-known cause of iliac fossa pain. Postgrad Med J 1989; 65: 632e5. 33 Liszka TG, Dellon AL, Manson PN. Iliohypogastric nerve entrapment following abdominoplasty. Plast Reconstr Surg 1994; 93: 181e4. 34 Tipton JS. Obturator neuropathy. Curr Rev Musculoskelet Med 2008; 1: 234e7. 35 Curtiss Jr PH, Kincaid WE. Transitory demineralization of the hip in pregnancy. A report of three cases. J Bone Joint Surg Am 1959; 41-A: 1327e33. 36 Hunder GG, Kelly PJ. Transient osteoporosis of the hip: a clinical syndrome? Arthritis Rheum 1967; 10: 285. 37 Escola A, Pons M, Pasarin A, Majo J. Idiopathic transient osteoporosis of the pelvis in a non-pregnant young woman: a case study. Hip Int 2009; 19: 71e4. 38 Willis-Owen CA, Daurka JS, Chen A, Lewis A. Bilateral femoral neck fractures due to transient osteoporosis of pregnancy: a case report. Cases J 2008; 1: 120. 39 Aynaci O, Kerimoglu S, Ozturk C, Saracoglu M. Bilateral non-traumatic acetabular and femoral neck fractures due to pregnancy-associated osteoporosis. Arch Orthop Trauma Surg 2008; 128: 313e6. 40 Beaulieu JG, Razzano CD, Levine RB. Transient osteoporosis of the hip in pregnancy. Clin Orthop Relat Res 1976; 115: 165e8. 41 Bloem JL. Transient osteoporosis of the hip: MR imaging. Radiology 1988; 167: 753e5.
Pregnancy testing is mandatory in all women of childbearing age who suffer trauma. Initial management is unchanged in both the pregnant and non-pregnant trauma patient e ATLS protocols should be adhered to. Radiation exposure should be minimized where possible. However, where a radiological study is indicated in emergency, there should be no hesitation to proceed with the investigation. Elective procedures should generally be postponed until after delivery. There is no absolute contraindication to surgery during an emergency. Pregnancy-related conditions can generally be treated successfully through conservative management. While back pain is common in pregnancy, red-flag symptoms for cauda equina should be considered and ruled out early to avoid potential neurological deficit. A
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