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Femoral and tibial fractures
ORTHOPAEDICS: LOWER LIMB
Femoral and tibial fractures
knee. The diaphysis is roughly circular in cross-section with the prominent ridge of the linea aspera seen posteriorly. In the sagittal plane it forms an anterior bow with an average radius of curvature of 8 m. In the coronal plane the axis of the femoral diaphysis slopes towards the midline as it approaches the knee forming an average angle of 81 degrees with the joint line of the condyles. Powerful muscles cloak the femur and when fractured these muscles act as deforming forces on the bone fragments. An understanding of these force vectors aids the treating surgeon in manipulating the fragments and achieving fracture reduction. The gluteal muscles insert on the greater trochanter and abduct the proximal segment. The iliopsoas tendon inserts on the lesser trochanter and flexes and externally rotates the proximal fragment together with the short external rotators. The adductor muscle group inserting on the medial aspect of the distal femur tend to pull the distal segment into varus. The gastrocnemius originates on the posterior aspect of the distal femur and will pull a distal femoral fracture into hyperextension. Bone demonstrates viscoelastic properties in which its ability to accommodate load depends on the rate at which it is applied. In practical terms this means that a force which is applied gradually will be better tolerated than the same force applied rapidly. With rapid deformation the bone behaves in a more brittle fashion increasing susceptibility to fracture. The fracture pattern is related to the mechanism of injury; a spiral fracture typically results from a torsional injury whereas transverse fractures result from a sideways force vector. Oblique fractures are usually a result of combined axial and transverse forces. Higher energy impacts result in greater degrees of comminution or segmental fractures.
David Bartle John Keating
Abstract Femoral shaft fractures have a bimodal distribution with high energy injuries in young patients and an increasing incidence of osteoporotic fractures in elderly patients. Adult diaphyseal fractures are invariably managed operatively and the procedure most commonly performed is stabilisation with antegrade reamed intramedullary nailing. Retrograde nailing is also used for specific indications. Plating is still used for more distal fractures. External fixation and non-operative treatment by traction are seldom used now due to high risk of complications. Tibial shaft fractures are the most common long bone fracture and the most common open long bone fracture (21%). Reamed intramedullary nailing is the most common treatment for unstable fractures. Low energy undisplaced fractures can be treated non-operatively in a cast or brace. Plating is not often used for diaphyseal injuries but is useful for metaphyseal fractures. External fixation is still commonly used for some severe open injuries or to correct deformity. Complications of femoral and tibial fractures include nonunion, malunion and infection in association with open fractures. Compartment syndrome complicates 2-10% of tibial fractures. For closed fractures the incidence of all of these complications should be less than 5%. Open fractures have a greater risk of complication which is generally proportional to the energy of the injury.
Keywords Femoral fractures; fracture management; intramedullary nailing; skeletal trauma; tibial fractures; wounds and injuries
Classification The most comprehensive skeletal classification system is that € r Osteosynthesefragen/ developed by the Arbeitsgemeinschaft fu Orthopaedic Trauma Association (AO/OTA) group. This is a hierarchical alphanumeric system which covers the spectrum of fractures by first describing the location of the fracture and then the morphology. Long-bone fracture location is described using two numbers. The first numerical descriptor denotes the effected long bone with three representing the femur. The second numerical descriptor denotes the location within that bone by a number 1, 2, 3 representing proximal, diaphyseal and distal respectively. The morphology of the fracture is then coded and for diaphyseal injuries A refers to simple, B to wedge and C to complex fractures. Additional numbers can be used to further specify the group and subgroup.
Femoral fractures Epidemiology The incidence of femoral fractures is 10 per 100,000 with a bimodal distribution. High-energy femoral fractures are more common in young males with usual mechanisms being motor vehicle crashes and sporting injuries. However the incidence of high-speed road traffic accidents is falling and therefore the number of these injuries is reducing. The second peak in distribution is seen in the elderly in which fragility fractures secondary to osteoporosis are common. This group of patients is increasing as a proportion of the population and therefore the volume of these osteoporotic fractures is continuing to rise.
Early management Patients involved in high-energy injuries require management using Advanced Trauma Life Support (ATLS) principles to evaluate and simultaneously address life-threatening injuries. The primary survey will typically detect an unstable femoral fracture and a full secondary survey must be completed to identify other injuries. Specifically it is necessary to assess for any open wounds communicating with the fracture and to assess the distal neurologic and vascular status. Femoral fractures in the elderly are more commonly due to low-energy mechanisms such as falls from standing height. Assessment should search for the cause of the fall, any prodromal symptoms and screen for both metabolic bone disease and malignancy.
Anatomy and biomechanics The diaphyseal portion of the femur extends from the lesser trochanter to the metaphyseal flare of the condylar region of the
David Bartle FRACS(Orth) is a Trauma Fellow at the Royal Infirmary of Edinburgh, Edinburgh, UK. Conflicts of interest: none declared. John Keating FRCS(Orth) is a Consultant Orthopaedic Surgeon at the Royal Infirmary of Edinburgh, Edinburgh, UK. Conflicts of interest: none declared.
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Ó 2013 Elsevier Ltd. All rights reserved.
ORTHOPAEDICS: LOWER LIMB
Injuries associated with femoral shaft fractures C C C C C C C
Relative indications for retrograde femoral nail
Posterior wall acetabular fractures Hip dislocation Femoral head fractures Femoral neck or intertrochanteric fractures Hoffa fracture (posterior femoral condyle fracture) Patellar fracture Posterior cruciate ligament rupture
C C C C C C C
Box 1
Box 2
There are specific situations in which retrograde passage of the nail confers certain advantages. A retrograde nail is introduced through the intercondylar notch of the knee passing up the medullary canal to the proximal femur. Fracture reduction can be more easily achieved using limb manipulation rather than relying on traction and this makes it easier to manage injuries when there is associated pelvic fractures or an ipsilateral tibial fracture. A distal entry point allows distal fractures to be better aligned and stabilized. Access through the knee rather than at the level of the hip has advantages when the patient is obese or if additional surgical approaches will be required to the pelvis. The relative indications for retrograde nailing are listed in Box 2. Subtrochanteric fractures present unique challenges due to the powerful deforming muscle forces acting on the proximal femur. These fractures are vulnerable to malunion and conventional proximal interlocking locking screws do not provide adequate stability. In these situations the preferred implant has become a cephalomedullary nail in which locking bolts are advanced through the rod up the femoral neck to rest in the femoral head thereby improving proximal stability. Achieving correct implant position is more technically demanding with this procedure. Concomitant diaphyseal and intertrochanteric/neck fractures need to have each component considered in turn as principles of fixation and potential complications are different. Ipsilateral pertrochanteric fractures can usually have both fractures fixed with a cephalomedullary nail. However if the proximal fracture is a displaced intracapsular fracture then this must receive priority. Anatomic reduction is necessary to minimize the risk of fixation failure, nonunion and avascular necrosis. Screw fixation of the intracapsular fracture with plate or retrograde nail fixation of the diaphyseal component would be common alternatives to a cephalomedullary nail in this situation.
Paediatric femoral fractures in children less than 4 years of age must always raise the question of non-accidental injury and mandate a thorough assessment, clear documentation and referral as required. All suspected femoral fractures should be imaged with anteroposterior (AP) and lateral plain film images of the entire bone including the knee and the hip and an AP view of the pelvis. CT scans are not needed for diaphyseal femoral fractures but will be required for complex intra-articular distal femoral fractures or associated pelvic and acetabular fractures. Angiography is required in cases with suspected vascular injury. Associated injuries are common and must be sought to ensure that they are not overlooked. Ipsilateral limb injuries are common with 6% of femoral shaft fractures being associated with a concomitant intertrochanteric/femoral neck fracture. Other associated injuries which should be considered are listed in Box 1. Non-operative management Until the middle of the 20th century non-operative treatment on traction was the standard method of treating femoral fractures and in many parts of the developing world this remains the standard of care. Non-operative management involves a period of immobilization on traction until sufficient callus has formed to allow mobilization in a hinged cast termed a cast brace until union is complete. The usual duration of traction was 2e3 months. Some degree of malunion was common, as was knee stiffness and other complications of immobilization including deep vein thrombosis, pressure sores, and urinary tract and respiratory infections. Non-operative management for adult diaphyseal fractures in the developed world is now rare. Operative management Intramedullary nailing is the treatment of choice for most adult diaphyseal femoral fractures and this should ideally be performed within the first 24 hours of injury. A reamed locked antegrade nail is the most common implant used. The exact nail entry depends on the specific design of the implant which is either the prominence of the greater trochanter or the piriformis fossa. A guide wire is passed from the entry point down the medullary space of proximal and distal fragments thereby bridging the fracture. Reaming is used to allow for a nail that closely fits the internal diameter of the diaphysis to improve stability. After insertion of the nail interlocking screws above and below the fracture pass through the bony cortices and the nail providing rotation and length stability (Figure 1).
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Morbid obesity Distal third fracture Ipsilateral femoral and tibial shaft fracture Pregnancy to reduce radiation dose Proximal implant, e.g. THR or femoral neck screws Proximal femoral deformity Ipsilateral tibial shaft fractures
Plating of diaphyseal femoral fractures is no longer widely used as it is technically demanding, and associated with higher rates of fixation failure, implant breakage and nonunion when compared to intramedullary nailing. However it has a role in diaphyseal fractures which extend down to the metaphyseal and condylar region of the knee. In this situation a nail alone is unlikely to confer adequate stability whereas a plate allows for multiple screws to purchase the distal bone fragments and therefore achieve greater stability. Several proprietary plate designs allow for insertion using minimally invasive techniques. Periprosthetic fractures adjacent to hip and knee joint replacements are now seen commonly and
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ORTHOPAEDICS: LOWER LIMB
e14 days post-injury. The indications for using damage control principles are still being defined and in most clinical situations early definitive stabilization is the management of choice. Use of external fixation for definitive management is associated with a high rate of pin tract infection, malunion and knee joint stiffness. Paediatric femoral fractures Management of paediatric femoral fractures differs from adult care in three main ways. The first is that in the younger age group bone heals rapidly and remodels well meaning that non-operative management has a much greater role. The second is that the physis must be protected to prevent growth arrest precluding conventional nail designs. Thirdly, blood supply to the femoral head is reliant upon extra-osseous means (trochanteric anastomisis) rather than intra-osseous supply. Antegrade femoral nailing places this anastomosis at risk and therefore the possibility of femoral head osteonecrosis. For these reasons it is generally advised that nailing should be avoided until skeletal maturity. For young children with a weight less than 14 kg, gallows traction or spica cast may be used. In older children weighing between 14 and 50 kg then traction, spica cast, or now quite commonly, flexible intramedullary nails inserted at the level of the knee. In young adolescents flexible intramedullary nails or external fixators are used. In late adolescence, depending on skeletal maturity standard reamed nailing can be used.
Tibial fractures Epidemiology The tibia is the most commonly injured long bone with an incidence of 26 per 100,000. Males are more commonly affected and the mean age is 37 although the distribution is also bimodal. At a rate of 21% it is the long bone most commonly associated with an open injury. The mechanism in a young adult requires relatively high energy although in contrast to femoral fractures these are more commonly seen from sporting injuries. The elderly population with osteoporosis are susceptible to sustaining tibial fractures with much less force. Anatomy and biomechanics The tibia takes approximately 80% of the axial load of the lower leg. It is roughly triangular in cross section. The anteromedial surface is largely subcutaneous which contributes to the susceptibility of open injury.
Figure 1 Postoperative radiograph of bilateral femur fractures. The left has been treated with a reamed antegrade nail whereas on the right a retrograde nail has been used. Note both fractures healing with abundant callus formation. The nails are locked to maintain length and prevent rotational or angular deformity occurring.
Classification Tibial diaphyseal fractures can be classified according to the AO/ OTA system as described above. Open fractures are classified by the modified Gustilo and Anderson system. Grade I injuries are low-energy fractures with a wound of less than 1 cm. Grade II injuries are fractures as a result of moderate energy with a wound of between 1 cm and 10 cm but without significant deep soft tissue damage or contamination. Grade III injuries are all the result of high-energy trauma and are associated with deep soft tissue damage and/or contamination. Grade III injuries are subdivided into three sub-categories. Grade IIIA injuries have a wound of greater than 10 cm with deep soft tissue contamination or are high energy fractures with a segmental configuration, but allow direct soft tissue closure. Grade IIIB injuries usually require closure with a local or free flap and may have significant bone
frequently treated by plate fixation. Plating also has a certain indications in the paediatric population as discussed below. External fixation is mainly used when definitive fixation with nail or plate fixation is not advisable. It is often used in military conflicts when facilities for definitive fixation are not available. In the setting of polytrauma with an ISS of greater than 40 or with severe thoracic and abdominal trauma then temporizing surgery known as damage control surgery may be undertaken. Skeletal stability is achieved with external fixation with delayed definitive care performed once the patient’s overall condition improves, typically 10
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ORTHOPAEDICS: LOWER LIMB
loss and periosteal stripping. A grade IIIC open fracture is associated with vascular injury requiring repair.
closed fractures. Frequent clinic visits and regular radiographs are necessary to ensure maintenance of fracture position. Nonoperative care is the management of choice for most paediatric tibial fractures, but is rarely used for displaced adult fractures.
Management Initial management follows the same principles as outlined for the femur. All high-energy injuries must be initially assessed and managed according to ATLS principles. Distal neurological and vascular status should be assessed. Open wounds or threatened skin must be inspected and open wounds should be initially irrigated in the emergency department, sterile dressing placed and appropriate antibiotic and tetanus cover provided. All unstable tibial fractures should be provisionally splinted in an above knee plaster cast or similar device with repeat assessment of vascular perfusion and neurologic function. If there is any vascular compromise a vascular opinion should be sought. Radiographs, AP and lateral, from the knee to the ankle must be obtained. The tibia frequently fractures in a spiral manner and the distal extent may extend to the ankle mortice which is important feature to assess. Analgesia will be required but nerve blocks should be avoided as they may mask an impending compartment syndrome. Compartment monitoring is now frequently used to facilitate early recognition of this complication. Normal compartment pressures should be less than 30 mmHg and there should always be a differential of more than 30 mmHg between the compartment pressure and the diastolic blood pressure to allow adequate perfusion of the compartment.
Operative management Intramedullary nailing: displaced fractures are invariably unstable and generally managed operatively with intramedullary nailing (Figure 2). The concept is similar to that outlined for femoral fractures. An entry point is developed behind the patella tendon and following placement of the guide-wire past the fracture and subsequent reaming an appropriately sized nail is placed and interlocked with at least one screw proximal and one screw distal. Open fractures are initially managed with thorough wound debridement and irrigation followed by skeletal stabilization. This is usually with an intramedullary nail but external fixation is also a common choice. Circular fine wire skeletal external fixators can be used if there is bone loss as they allow initial shortening and subsequent lengthening, which may simplify management of a complex problem. Should the soft tissue defect require flap closure this should be carried out as soon as possible, preferably with 48e72 hours. Proximal and distal fractures are more difficult than midshaft fractures to reduce and stabilize with intramedullary devices. Plate fixation can be considered if the soft tissue envelope is in good condition. Plating has a role in the management of tibial fractures in which there are extensions towards the knee or the ankle which cannot be adequately controlled with intramedullary nailing. Plate fixation allows for increased screw hold in the metaphyseal bone which assists with achieving and maintaining reduction. Specifically designed plates allow for multiple screw placement in periarticular fractures. Plate fixation is also of use in the adolescent with open
Non-operative management Undisplaced and stable tibial fractures may be managed nonoperatively in a long leg cast for 4e6 weeks followed by conversion to a below knee cast or brace until union occurs, which typically occurs between 12 and 20 weeks in the majority of
Figure 2 (a) Distal third tibial shaft fracture; (b) postoperative radiograph after fixation with a locked nail. The tubing seen on the radiograph is linked to a compartment pressure monitor to detect any evidence of compartment syndrome developing in the postoperative period.
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Ó 2013 Elsevier Ltd. All rights reserved.
ORTHOPAEDICS: LOWER LIMB
physis and an unstable fracture pattern which is not being adequately supported by a cast. Plate fixation is associated with a definite risk of wound complications and this increases with distal fractures, poor soft tissues and other risk factors such as smoking and diabetes. Deep infection often results in osteomyelitis and may be very difficult to manage.
monitoring the compartment pressure as described above. A prompt four-compartment fasciotomy of the leg is the mandatory treatment. Failure to do this will result in muscle necrosis, sometimes complicated by acute renal failure secondary to myoglobin from muscle breakdown entering the circulation and causing acute tubular necrosis. Later the limb function will be adversely affected by development of a Volkmann’s ischaemic contracture.
External fixation can be used as definitive treatment for open and closed tibial shaft fractures. However it is associated with higher rates of malunion and reoperation, and nail fixation is preferred for most situations. As indicated, fine wire external fixators such as the Ilizarov or Taylor spatial frame can be used to correct complex skeletal deformity and leg length discrepancy. They can be used for high-energy open tibial fractures with bone loss. However they are most frequently used for management of late tibial malunion, particularly in the presence of infection, shortening and bone loss.
Vascular injury and amputation The incidence of vascular injury is low in both femoral and tibial shaft fractures and no higher than 1%. It is more commonly associated with open fractures. Femoral shaft fractures with vascular injury can be treated with rapid skeletal fixation and vascular repair. Temporary vascular shunting may be required during skeletal stabilization. Limb salvage occurs in most cases but amputation rates are 25% and functional outcome in salvaged limbs is often poor. Grade IIIC open fractures of the tibia are generally associated with extensive soft tissue damage and amputation is the outcome in the majority of cases. Severe open tibial fractures may need to be treated by early amputation if the predicted functional outcome is likely to be inferior to limb salvage. Numerous scores for assessing the limb to guide the decision have been described (e.g. Mangled Extremity Severity Score (MESS), Hanover score) but have not be shown in clinical studies to be a sensitive or specific guide to decision making. Relative indications for amputation are a warm ischaemic time in excess of 6 hours, transection of the posterior tibial nerve, and associated severe crushing injuries of the foot or leg that would preclude good long-term function.
Complications of femoral and tibial fractures Modern techniques of operative management have been associated with low rates of complications, particularly with closed femoral and tibial shaft fractures. Deep vein thrombosis (DVT) and pulmonary embolism Thromboembolic complications are uncommon with closed femoral and tibial fractures, particularly if treated with early mobilization. Although evidence for thromboprophylaxis is limited most patients are treated with a low-molecular-weight heparin which in hospital.
Infection Infection is more common in open fractures. The incidence is lower in open femur fractures where the rate should be less than 5% but in open tibial fractures is between 5 and 10% for higher grade injuries. General principles include the use of targeted antibiotics and maintaining skeletal stability until the fracture has united at which point the implant should be removed. Should the infection not be controlled using this strategy more aggressive surgery will be required to remove infected bone and metal wear and adopt an alternative strategy of stabilization.
Fat embolism syndrome Fat embolism is a clinical syndrome characterized principally by respiratory dysfunction. Fat emboli occur in 90% of those with severe long-bone fractures but only 1e5% of these cases will be symptomatic. The condition is mainly seen in multiple trauma patients particularly those with femoral shaft fractures but it can occur in isolated tibial fractures although this is rare. Signs and symptoms typically occur 24e72 hours following trauma and may include dyspnoea, agitation and petechial rash. Pathogenesis involves a mechanical pathway of obstruction by the fat globules and a biochemical pathway of endothelial injury from the toxic effect of fatty acids. Some emboli can bypass the lung and lodge in other areas resulting in multi-organ dysfunction. The process can also result in disseminated intravascular coagulopathy and lead onto a systemic inflammatory response. Treatment is generally supportive and may require high-dependency or intensive care facilities. There is good clinical evidence that early stabilization of long bone fractures minimizes the risk of this syndrome developing.
Nonunion Nonunion of tibial fractures is more common than femoral fractures due to lack of circumferential muscular cover and consequently a poorer blood supply. The incidence of nonunion in closed femoral and tibial shaft fractures treated by intramedullary nailing should be no higher than 2%. The risk is higher in heavy smokers, patients with systemic disease and with use of high doses of non-steroidal anti-inflammatory analgesics. Most closed femoral and tibial fractures will be united or showing radiographic evidence of progression to uneventful union by 20 weeks and operative intervention should be considered if this is not the case. Open fractures are more prone to nonunion in part due to the higher energy injury mechanism with increased disruption of the bone blood supply. In general grade IIIA and B open fractures have an increased risk and up to 50% of grade IIIB open tibial fractures may require further surgery to achieve union. Bone loss in association with open fractures greater increases the risk. In the absence of bone loss exchange intramedullary nailing will be effective in most cases in nonunion following primary nail
Compartment syndrome This is most frequently encountered with tibial shaft fractures. The overall incidence in closed tibial shaft fractures is 2% but with higher energy injuries the incidence may approach 10%. It does occur in open fractures unless the soft tissue disruption is extensive. The diagnosis is suggested by disproportionate pain and the presence of increased pain on passive flexion and extension of the foot. Pulses are usually normal and neurological compromise is a late sign. The most reliable way to make the diagnosis is by
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Tibial shaft fractures. In: Petrisor BA, Bhandari M, Schemitsch E, eds. Rockwood and Green’s fractures in adults. 7th edn. Lippincott Williams & Wilkins, 2010.
fixation. Nonunion following plate fixation usually requires replating and bone grafting. If there is bone loss after open fractures then bone grafting is usually necessary as a planned procedure within 6 months of injury. Extensive segmental bone loss of 6 cm or more will usually require complex reconstruction with bone transport.
SPECIFIC PUBLICATIONS Aderinto J, Walmsley P, Keating JF. Fractures of the tibial spine: epidemiology and outcome. Knee 2008 Jun; 15: 164e7. Epub 2008 Mar 5. Bone LB, Johnson KD. Early versus delayed stabilization of femoral shaft fractures. A randomized study. J Bone Joint Surg Am 1989; 71: 336e40. Bosse MJ, Kellam JF. Damage control orthopaedic surgery: a strategy for the orthopaedic care of the critically injured patient. In: Browner BD, ed. Skeletal trauma. 4th edn. Saunders, 2008. Bosse MJ, MacKenzie EJ, Kellam JF, et al. A prospective evaluation of the clinical utility of the lower-extremity injury-severity scores. J Bone Joint Surg Am 2001; 83-A: 3e14. Brundage SI, McGhan R, Jurkovich GJ, et al. Timing of femur fracture fixation: effect on outcome in patients with thoracic and head injuries. J Trauma 2002; 52: 299e307. Keating JF, Blachut P, Court-Brown CM, O’Brien PJ. Reamed nailing of grade IIIB open tibial fractures. J Bone Joint Surg 2000; 82B: 1113e6. Keating JF, Robinson CM, Simpson AHR. Management of bone loss after trauma. J Bone Joint Surg 2005; 87B: 142e50. McQueen MM, Christie J, Court-Brown CM. Compartment pressures after intramedullary nailing of the tibia. J Bone Joint Surg Br 1990; 72e73: 395e7. Mitchell SE, Keating JF, Robinson CM. The treatment of open femoral fractures with bone loss. J Bone Joint Surg Br 2010 Dec; 92: 1678e84. Pape HC, Ciannoudis P, Krettek C. The timing of fracture treatment in polytrauma patients: relevance of damage control orthopedic surgery. Am J Surg 2002; 183: 622e9.
Malunion This is most commonly associated with non-operative treatment or with external fixation. Rates of malunion may be as high as 40% with these methods, although the degree of malunion is frequently not severe enough to necessitate operative correction. In patients undergoing internal fixation with a nail or plate the rate of malunion is much lower and should not exceed 5%. In most cases it is attributable to technical error at the time of surgery with failure to restore a satisfactory reduction. Shortening in excess of 3e4 cm, angulation or rotation deformity in excess of 10 degrees may be associated with functional impairment and require operative correction. Anterior knee pain Anterior knee pain is relatively common following tibial intramedullary nailing with reported incidence in the order of 50%. This may be related to the presence of metal wear and an improvement in symptoms is seen in the majority of patients following implant removal. A
FURTHER READING GENERAL Femoral shaft fractures. In: Nork SE, ed. Rockwood and Green’s fractures in adults. 7th edn. Lippincott Williams & Wilkins, 2010.
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Ó 2013 Elsevier Ltd. All rights reserved.
Femoral and tibial fractures
knee. The diaphysis is roughly circular in cross-section with the prominent ridge of the linea aspera seen posteriorly. In the sagittal plane it forms an anterior bow with an average radius of curvature of 8 m. In the coronal plane the axis of the femoral diaphysis slopes towards the midline as it approaches the knee forming an average angle of 81 degrees with the joint line of the condyles. Powerful muscles cloak the femur and when fractured these muscles act as deforming forces on the bone fragments. An understanding of these force vectors aids the treating surgeon in manipulating the fragments and achieving fracture reduction. The gluteal muscles insert on the greater trochanter and abduct the proximal segment. The iliopsoas tendon inserts on the lesser trochanter and flexes and externally rotates the proximal fragment together with the short external rotators. The adductor muscle group inserting on the medial aspect of the distal femur tend to pull the distal segment into varus. The gastrocnemius originates on the posterior aspect of the distal femur and will pull a distal femoral fracture into hyperextension. Bone demonstrates viscoelastic properties in which its ability to accommodate load depends on the rate at which it is applied. In practical terms this means that a force which is applied gradually will be better tolerated than the same force applied rapidly. With rapid deformation the bone behaves in a more brittle fashion increasing susceptibility to fracture. The fracture pattern is related to the mechanism of injury; a spiral fracture typically results from a torsional injury whereas transverse fractures result from a sideways force vector. Oblique fractures are usually a result of combined axial and transverse forces. Higher energy impacts result in greater degrees of comminution or segmental fractures.
David Bartle John Keating
Abstract Femoral shaft fractures have a bimodal distribution with high energy injuries in young patients and an increasing incidence of osteoporotic fractures in elderly patients. Adult diaphyseal fractures are invariably managed operatively and the procedure most commonly performed is stabilisation with antegrade reamed intramedullary nailing. Retrograde nailing is also used for specific indications. Plating is still used for more distal fractures. External fixation and non-operative treatment by traction are seldom used now due to high risk of complications. Tibial shaft fractures are the most common long bone fracture and the most common open long bone fracture (21%). Reamed intramedullary nailing is the most common treatment for unstable fractures. Low energy undisplaced fractures can be treated non-operatively in a cast or brace. Plating is not often used for diaphyseal injuries but is useful for metaphyseal fractures. External fixation is still commonly used for some severe open injuries or to correct deformity. Complications of femoral and tibial fractures include nonunion, malunion and infection in association with open fractures. Compartment syndrome complicates 2-10% of tibial fractures. For closed fractures the incidence of all of these complications should be less than 5%. Open fractures have a greater risk of complication which is generally proportional to the energy of the injury.
Keywords Femoral fractures; fracture management; intramedullary nailing; skeletal trauma; tibial fractures; wounds and injuries
Classification The most comprehensive skeletal classification system is that € r Osteosynthesefragen/ developed by the Arbeitsgemeinschaft fu Orthopaedic Trauma Association (AO/OTA) group. This is a hierarchical alphanumeric system which covers the spectrum of fractures by first describing the location of the fracture and then the morphology. Long-bone fracture location is described using two numbers. The first numerical descriptor denotes the effected long bone with three representing the femur. The second numerical descriptor denotes the location within that bone by a number 1, 2, 3 representing proximal, diaphyseal and distal respectively. The morphology of the fracture is then coded and for diaphyseal injuries A refers to simple, B to wedge and C to complex fractures. Additional numbers can be used to further specify the group and subgroup.
Femoral fractures Epidemiology The incidence of femoral fractures is 10 per 100,000 with a bimodal distribution. High-energy femoral fractures are more common in young males with usual mechanisms being motor vehicle crashes and sporting injuries. However the incidence of high-speed road traffic accidents is falling and therefore the number of these injuries is reducing. The second peak in distribution is seen in the elderly in which fragility fractures secondary to osteoporosis are common. This group of patients is increasing as a proportion of the population and therefore the volume of these osteoporotic fractures is continuing to rise.
Early management Patients involved in high-energy injuries require management using Advanced Trauma Life Support (ATLS) principles to evaluate and simultaneously address life-threatening injuries. The primary survey will typically detect an unstable femoral fracture and a full secondary survey must be completed to identify other injuries. Specifically it is necessary to assess for any open wounds communicating with the fracture and to assess the distal neurologic and vascular status. Femoral fractures in the elderly are more commonly due to low-energy mechanisms such as falls from standing height. Assessment should search for the cause of the fall, any prodromal symptoms and screen for both metabolic bone disease and malignancy.
Anatomy and biomechanics The diaphyseal portion of the femur extends from the lesser trochanter to the metaphyseal flare of the condylar region of the
David Bartle FRACS(Orth) is a Trauma Fellow at the Royal Infirmary of Edinburgh, Edinburgh, UK. Conflicts of interest: none declared. John Keating FRCS(Orth) is a Consultant Orthopaedic Surgeon at the Royal Infirmary of Edinburgh, Edinburgh, UK. Conflicts of interest: none declared.
SURGERY 31:9
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Ó 2013 Elsevier Ltd. All rights reserved.
ORTHOPAEDICS: LOWER LIMB
Injuries associated with femoral shaft fractures C C C C C C C
Relative indications for retrograde femoral nail
Posterior wall acetabular fractures Hip dislocation Femoral head fractures Femoral neck or intertrochanteric fractures Hoffa fracture (posterior femoral condyle fracture) Patellar fracture Posterior cruciate ligament rupture
C C C C C C C
Box 1
Box 2
There are specific situations in which retrograde passage of the nail confers certain advantages. A retrograde nail is introduced through the intercondylar notch of the knee passing up the medullary canal to the proximal femur. Fracture reduction can be more easily achieved using limb manipulation rather than relying on traction and this makes it easier to manage injuries when there is associated pelvic fractures or an ipsilateral tibial fracture. A distal entry point allows distal fractures to be better aligned and stabilized. Access through the knee rather than at the level of the hip has advantages when the patient is obese or if additional surgical approaches will be required to the pelvis. The relative indications for retrograde nailing are listed in Box 2. Subtrochanteric fractures present unique challenges due to the powerful deforming muscle forces acting on the proximal femur. These fractures are vulnerable to malunion and conventional proximal interlocking locking screws do not provide adequate stability. In these situations the preferred implant has become a cephalomedullary nail in which locking bolts are advanced through the rod up the femoral neck to rest in the femoral head thereby improving proximal stability. Achieving correct implant position is more technically demanding with this procedure. Concomitant diaphyseal and intertrochanteric/neck fractures need to have each component considered in turn as principles of fixation and potential complications are different. Ipsilateral pertrochanteric fractures can usually have both fractures fixed with a cephalomedullary nail. However if the proximal fracture is a displaced intracapsular fracture then this must receive priority. Anatomic reduction is necessary to minimize the risk of fixation failure, nonunion and avascular necrosis. Screw fixation of the intracapsular fracture with plate or retrograde nail fixation of the diaphyseal component would be common alternatives to a cephalomedullary nail in this situation.
Paediatric femoral fractures in children less than 4 years of age must always raise the question of non-accidental injury and mandate a thorough assessment, clear documentation and referral as required. All suspected femoral fractures should be imaged with anteroposterior (AP) and lateral plain film images of the entire bone including the knee and the hip and an AP view of the pelvis. CT scans are not needed for diaphyseal femoral fractures but will be required for complex intra-articular distal femoral fractures or associated pelvic and acetabular fractures. Angiography is required in cases with suspected vascular injury. Associated injuries are common and must be sought to ensure that they are not overlooked. Ipsilateral limb injuries are common with 6% of femoral shaft fractures being associated with a concomitant intertrochanteric/femoral neck fracture. Other associated injuries which should be considered are listed in Box 1. Non-operative management Until the middle of the 20th century non-operative treatment on traction was the standard method of treating femoral fractures and in many parts of the developing world this remains the standard of care. Non-operative management involves a period of immobilization on traction until sufficient callus has formed to allow mobilization in a hinged cast termed a cast brace until union is complete. The usual duration of traction was 2e3 months. Some degree of malunion was common, as was knee stiffness and other complications of immobilization including deep vein thrombosis, pressure sores, and urinary tract and respiratory infections. Non-operative management for adult diaphyseal fractures in the developed world is now rare. Operative management Intramedullary nailing is the treatment of choice for most adult diaphyseal femoral fractures and this should ideally be performed within the first 24 hours of injury. A reamed locked antegrade nail is the most common implant used. The exact nail entry depends on the specific design of the implant which is either the prominence of the greater trochanter or the piriformis fossa. A guide wire is passed from the entry point down the medullary space of proximal and distal fragments thereby bridging the fracture. Reaming is used to allow for a nail that closely fits the internal diameter of the diaphysis to improve stability. After insertion of the nail interlocking screws above and below the fracture pass through the bony cortices and the nail providing rotation and length stability (Figure 1).
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Morbid obesity Distal third fracture Ipsilateral femoral and tibial shaft fracture Pregnancy to reduce radiation dose Proximal implant, e.g. THR or femoral neck screws Proximal femoral deformity Ipsilateral tibial shaft fractures
Plating of diaphyseal femoral fractures is no longer widely used as it is technically demanding, and associated with higher rates of fixation failure, implant breakage and nonunion when compared to intramedullary nailing. However it has a role in diaphyseal fractures which extend down to the metaphyseal and condylar region of the knee. In this situation a nail alone is unlikely to confer adequate stability whereas a plate allows for multiple screws to purchase the distal bone fragments and therefore achieve greater stability. Several proprietary plate designs allow for insertion using minimally invasive techniques. Periprosthetic fractures adjacent to hip and knee joint replacements are now seen commonly and
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e14 days post-injury. The indications for using damage control principles are still being defined and in most clinical situations early definitive stabilization is the management of choice. Use of external fixation for definitive management is associated with a high rate of pin tract infection, malunion and knee joint stiffness. Paediatric femoral fractures Management of paediatric femoral fractures differs from adult care in three main ways. The first is that in the younger age group bone heals rapidly and remodels well meaning that non-operative management has a much greater role. The second is that the physis must be protected to prevent growth arrest precluding conventional nail designs. Thirdly, blood supply to the femoral head is reliant upon extra-osseous means (trochanteric anastomisis) rather than intra-osseous supply. Antegrade femoral nailing places this anastomosis at risk and therefore the possibility of femoral head osteonecrosis. For these reasons it is generally advised that nailing should be avoided until skeletal maturity. For young children with a weight less than 14 kg, gallows traction or spica cast may be used. In older children weighing between 14 and 50 kg then traction, spica cast, or now quite commonly, flexible intramedullary nails inserted at the level of the knee. In young adolescents flexible intramedullary nails or external fixators are used. In late adolescence, depending on skeletal maturity standard reamed nailing can be used.
Tibial fractures Epidemiology The tibia is the most commonly injured long bone with an incidence of 26 per 100,000. Males are more commonly affected and the mean age is 37 although the distribution is also bimodal. At a rate of 21% it is the long bone most commonly associated with an open injury. The mechanism in a young adult requires relatively high energy although in contrast to femoral fractures these are more commonly seen from sporting injuries. The elderly population with osteoporosis are susceptible to sustaining tibial fractures with much less force. Anatomy and biomechanics The tibia takes approximately 80% of the axial load of the lower leg. It is roughly triangular in cross section. The anteromedial surface is largely subcutaneous which contributes to the susceptibility of open injury.
Figure 1 Postoperative radiograph of bilateral femur fractures. The left has been treated with a reamed antegrade nail whereas on the right a retrograde nail has been used. Note both fractures healing with abundant callus formation. The nails are locked to maintain length and prevent rotational or angular deformity occurring.
Classification Tibial diaphyseal fractures can be classified according to the AO/ OTA system as described above. Open fractures are classified by the modified Gustilo and Anderson system. Grade I injuries are low-energy fractures with a wound of less than 1 cm. Grade II injuries are fractures as a result of moderate energy with a wound of between 1 cm and 10 cm but without significant deep soft tissue damage or contamination. Grade III injuries are all the result of high-energy trauma and are associated with deep soft tissue damage and/or contamination. Grade III injuries are subdivided into three sub-categories. Grade IIIA injuries have a wound of greater than 10 cm with deep soft tissue contamination or are high energy fractures with a segmental configuration, but allow direct soft tissue closure. Grade IIIB injuries usually require closure with a local or free flap and may have significant bone
frequently treated by plate fixation. Plating also has a certain indications in the paediatric population as discussed below. External fixation is mainly used when definitive fixation with nail or plate fixation is not advisable. It is often used in military conflicts when facilities for definitive fixation are not available. In the setting of polytrauma with an ISS of greater than 40 or with severe thoracic and abdominal trauma then temporizing surgery known as damage control surgery may be undertaken. Skeletal stability is achieved with external fixation with delayed definitive care performed once the patient’s overall condition improves, typically 10
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loss and periosteal stripping. A grade IIIC open fracture is associated with vascular injury requiring repair.
closed fractures. Frequent clinic visits and regular radiographs are necessary to ensure maintenance of fracture position. Nonoperative care is the management of choice for most paediatric tibial fractures, but is rarely used for displaced adult fractures.
Management Initial management follows the same principles as outlined for the femur. All high-energy injuries must be initially assessed and managed according to ATLS principles. Distal neurological and vascular status should be assessed. Open wounds or threatened skin must be inspected and open wounds should be initially irrigated in the emergency department, sterile dressing placed and appropriate antibiotic and tetanus cover provided. All unstable tibial fractures should be provisionally splinted in an above knee plaster cast or similar device with repeat assessment of vascular perfusion and neurologic function. If there is any vascular compromise a vascular opinion should be sought. Radiographs, AP and lateral, from the knee to the ankle must be obtained. The tibia frequently fractures in a spiral manner and the distal extent may extend to the ankle mortice which is important feature to assess. Analgesia will be required but nerve blocks should be avoided as they may mask an impending compartment syndrome. Compartment monitoring is now frequently used to facilitate early recognition of this complication. Normal compartment pressures should be less than 30 mmHg and there should always be a differential of more than 30 mmHg between the compartment pressure and the diastolic blood pressure to allow adequate perfusion of the compartment.
Operative management Intramedullary nailing: displaced fractures are invariably unstable and generally managed operatively with intramedullary nailing (Figure 2). The concept is similar to that outlined for femoral fractures. An entry point is developed behind the patella tendon and following placement of the guide-wire past the fracture and subsequent reaming an appropriately sized nail is placed and interlocked with at least one screw proximal and one screw distal. Open fractures are initially managed with thorough wound debridement and irrigation followed by skeletal stabilization. This is usually with an intramedullary nail but external fixation is also a common choice. Circular fine wire skeletal external fixators can be used if there is bone loss as they allow initial shortening and subsequent lengthening, which may simplify management of a complex problem. Should the soft tissue defect require flap closure this should be carried out as soon as possible, preferably with 48e72 hours. Proximal and distal fractures are more difficult than midshaft fractures to reduce and stabilize with intramedullary devices. Plate fixation can be considered if the soft tissue envelope is in good condition. Plating has a role in the management of tibial fractures in which there are extensions towards the knee or the ankle which cannot be adequately controlled with intramedullary nailing. Plate fixation allows for increased screw hold in the metaphyseal bone which assists with achieving and maintaining reduction. Specifically designed plates allow for multiple screw placement in periarticular fractures. Plate fixation is also of use in the adolescent with open
Non-operative management Undisplaced and stable tibial fractures may be managed nonoperatively in a long leg cast for 4e6 weeks followed by conversion to a below knee cast or brace until union occurs, which typically occurs between 12 and 20 weeks in the majority of
Figure 2 (a) Distal third tibial shaft fracture; (b) postoperative radiograph after fixation with a locked nail. The tubing seen on the radiograph is linked to a compartment pressure monitor to detect any evidence of compartment syndrome developing in the postoperative period.
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physis and an unstable fracture pattern which is not being adequately supported by a cast. Plate fixation is associated with a definite risk of wound complications and this increases with distal fractures, poor soft tissues and other risk factors such as smoking and diabetes. Deep infection often results in osteomyelitis and may be very difficult to manage.
monitoring the compartment pressure as described above. A prompt four-compartment fasciotomy of the leg is the mandatory treatment. Failure to do this will result in muscle necrosis, sometimes complicated by acute renal failure secondary to myoglobin from muscle breakdown entering the circulation and causing acute tubular necrosis. Later the limb function will be adversely affected by development of a Volkmann’s ischaemic contracture.
External fixation can be used as definitive treatment for open and closed tibial shaft fractures. However it is associated with higher rates of malunion and reoperation, and nail fixation is preferred for most situations. As indicated, fine wire external fixators such as the Ilizarov or Taylor spatial frame can be used to correct complex skeletal deformity and leg length discrepancy. They can be used for high-energy open tibial fractures with bone loss. However they are most frequently used for management of late tibial malunion, particularly in the presence of infection, shortening and bone loss.
Vascular injury and amputation The incidence of vascular injury is low in both femoral and tibial shaft fractures and no higher than 1%. It is more commonly associated with open fractures. Femoral shaft fractures with vascular injury can be treated with rapid skeletal fixation and vascular repair. Temporary vascular shunting may be required during skeletal stabilization. Limb salvage occurs in most cases but amputation rates are 25% and functional outcome in salvaged limbs is often poor. Grade IIIC open fractures of the tibia are generally associated with extensive soft tissue damage and amputation is the outcome in the majority of cases. Severe open tibial fractures may need to be treated by early amputation if the predicted functional outcome is likely to be inferior to limb salvage. Numerous scores for assessing the limb to guide the decision have been described (e.g. Mangled Extremity Severity Score (MESS), Hanover score) but have not be shown in clinical studies to be a sensitive or specific guide to decision making. Relative indications for amputation are a warm ischaemic time in excess of 6 hours, transection of the posterior tibial nerve, and associated severe crushing injuries of the foot or leg that would preclude good long-term function.
Complications of femoral and tibial fractures Modern techniques of operative management have been associated with low rates of complications, particularly with closed femoral and tibial shaft fractures. Deep vein thrombosis (DVT) and pulmonary embolism Thromboembolic complications are uncommon with closed femoral and tibial fractures, particularly if treated with early mobilization. Although evidence for thromboprophylaxis is limited most patients are treated with a low-molecular-weight heparin which in hospital.
Infection Infection is more common in open fractures. The incidence is lower in open femur fractures where the rate should be less than 5% but in open tibial fractures is between 5 and 10% for higher grade injuries. General principles include the use of targeted antibiotics and maintaining skeletal stability until the fracture has united at which point the implant should be removed. Should the infection not be controlled using this strategy more aggressive surgery will be required to remove infected bone and metal wear and adopt an alternative strategy of stabilization.
Fat embolism syndrome Fat embolism is a clinical syndrome characterized principally by respiratory dysfunction. Fat emboli occur in 90% of those with severe long-bone fractures but only 1e5% of these cases will be symptomatic. The condition is mainly seen in multiple trauma patients particularly those with femoral shaft fractures but it can occur in isolated tibial fractures although this is rare. Signs and symptoms typically occur 24e72 hours following trauma and may include dyspnoea, agitation and petechial rash. Pathogenesis involves a mechanical pathway of obstruction by the fat globules and a biochemical pathway of endothelial injury from the toxic effect of fatty acids. Some emboli can bypass the lung and lodge in other areas resulting in multi-organ dysfunction. The process can also result in disseminated intravascular coagulopathy and lead onto a systemic inflammatory response. Treatment is generally supportive and may require high-dependency or intensive care facilities. There is good clinical evidence that early stabilization of long bone fractures minimizes the risk of this syndrome developing.
Nonunion Nonunion of tibial fractures is more common than femoral fractures due to lack of circumferential muscular cover and consequently a poorer blood supply. The incidence of nonunion in closed femoral and tibial shaft fractures treated by intramedullary nailing should be no higher than 2%. The risk is higher in heavy smokers, patients with systemic disease and with use of high doses of non-steroidal anti-inflammatory analgesics. Most closed femoral and tibial fractures will be united or showing radiographic evidence of progression to uneventful union by 20 weeks and operative intervention should be considered if this is not the case. Open fractures are more prone to nonunion in part due to the higher energy injury mechanism with increased disruption of the bone blood supply. In general grade IIIA and B open fractures have an increased risk and up to 50% of grade IIIB open tibial fractures may require further surgery to achieve union. Bone loss in association with open fractures greater increases the risk. In the absence of bone loss exchange intramedullary nailing will be effective in most cases in nonunion following primary nail
Compartment syndrome This is most frequently encountered with tibial shaft fractures. The overall incidence in closed tibial shaft fractures is 2% but with higher energy injuries the incidence may approach 10%. It does occur in open fractures unless the soft tissue disruption is extensive. The diagnosis is suggested by disproportionate pain and the presence of increased pain on passive flexion and extension of the foot. Pulses are usually normal and neurological compromise is a late sign. The most reliable way to make the diagnosis is by
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Tibial shaft fractures. In: Petrisor BA, Bhandari M, Schemitsch E, eds. Rockwood and Green’s fractures in adults. 7th edn. Lippincott Williams & Wilkins, 2010.
fixation. Nonunion following plate fixation usually requires replating and bone grafting. If there is bone loss after open fractures then bone grafting is usually necessary as a planned procedure within 6 months of injury. Extensive segmental bone loss of 6 cm or more will usually require complex reconstruction with bone transport.
SPECIFIC PUBLICATIONS Aderinto J, Walmsley P, Keating JF. Fractures of the tibial spine: epidemiology and outcome. Knee 2008 Jun; 15: 164e7. Epub 2008 Mar 5. Bone LB, Johnson KD. Early versus delayed stabilization of femoral shaft fractures. A randomized study. J Bone Joint Surg Am 1989; 71: 336e40. Bosse MJ, Kellam JF. Damage control orthopaedic surgery: a strategy for the orthopaedic care of the critically injured patient. In: Browner BD, ed. Skeletal trauma. 4th edn. Saunders, 2008. Bosse MJ, MacKenzie EJ, Kellam JF, et al. A prospective evaluation of the clinical utility of the lower-extremity injury-severity scores. J Bone Joint Surg Am 2001; 83-A: 3e14. Brundage SI, McGhan R, Jurkovich GJ, et al. Timing of femur fracture fixation: effect on outcome in patients with thoracic and head injuries. J Trauma 2002; 52: 299e307. Keating JF, Blachut P, Court-Brown CM, O’Brien PJ. Reamed nailing of grade IIIB open tibial fractures. J Bone Joint Surg 2000; 82B: 1113e6. Keating JF, Robinson CM, Simpson AHR. Management of bone loss after trauma. J Bone Joint Surg 2005; 87B: 142e50. McQueen MM, Christie J, Court-Brown CM. Compartment pressures after intramedullary nailing of the tibia. J Bone Joint Surg Br 1990; 72e73: 395e7. Mitchell SE, Keating JF, Robinson CM. The treatment of open femoral fractures with bone loss. J Bone Joint Surg Br 2010 Dec; 92: 1678e84. Pape HC, Ciannoudis P, Krettek C. The timing of fracture treatment in polytrauma patients: relevance of damage control orthopedic surgery. Am J Surg 2002; 183: 622e9.
Malunion This is most commonly associated with non-operative treatment or with external fixation. Rates of malunion may be as high as 40% with these methods, although the degree of malunion is frequently not severe enough to necessitate operative correction. In patients undergoing internal fixation with a nail or plate the rate of malunion is much lower and should not exceed 5%. In most cases it is attributable to technical error at the time of surgery with failure to restore a satisfactory reduction. Shortening in excess of 3e4 cm, angulation or rotation deformity in excess of 10 degrees may be associated with functional impairment and require operative correction. Anterior knee pain Anterior knee pain is relatively common following tibial intramedullary nailing with reported incidence in the order of 50%. This may be related to the presence of metal wear and an improvement in symptoms is seen in the majority of patients following implant removal. A
FURTHER READING GENERAL Femoral shaft fractures. In: Nork SE, ed. Rockwood and Green’s fractures in adults. 7th edn. Lippincott Williams & Wilkins, 2010.
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