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Evaluation of the limping child
SYMPOSIUM: SURGERY & ORTHOPAEDICS
Evaluation of the limping child
system. It should be smooth, rhythmical and energy efficient. Children’s gait patterns differ greatly from adults and it’s only by the age of 3e4 years that gait exhibits adult type characteristics. By 7 years the child’s gait is nearly identical to that of an adult. Children typically start walking between 10e18 months of age. At this stage it is common to see bowing (genu varum)of the legs. Children stand with a wide base of support to improve stability. An increase in lumbar lordosis is present due to lack of abdominal tone however this may also be a compensatory mechanism by placing the lumbar spine ‘facet’ joints into a closed pack position and hence improving stability by increasing afferent input. Gait is slow although ironically, cadence (number of steps per minute) is very high due to leg length and poor balance. As the child develops so does lower limb alignment, by 2e3 years of age typically the lower limb shows a ‘knock knee’ posture (genu valgum). They are now able to stand on one leg for longer due to improving hip abductor strength and balance. Cadence is also helped by an increasing leg length. At 4e6 years of age the majority of children have developed a medial longitudinal arch, however they still may present with a flexible ‘pes planus’ on weight bearing due to hypermobility and poor intrinsic muscle function. A congenital flat foot is not dependent on weight-bearing and is present at all times. It is also at this stage that the lower limb will begin to straighten into normal alignment. As muscle power and co-ordination improve the child is able to balance for longer on one leg and the majority of children are able to hop by 6e7 years of age.
Ian Roberts Gavin Cleary
Abstract Limping in children is common and may arise from a spectrum of disorders ranging from normal variations in gait development, through to potentially life threatening systemic disease. In this review we take the reader through the normal development of gait, then discuss normal variants of gait in order to identify pathological gait patterns. We aim to provide a framework for the holistic clinical assessment of the limping child and review in more detail some of the commoner diseases associated with limping. Finally some of the commoner pitfalls to establishing a correct diagnosis are presented along with suggestions that may help to improve the diagnostic yield.
Keywords Abnormal gait; Children; Limping
Introduction Accepting a limp as normal in a child risks failure to diagnose potentially significant pathology. Certain pathology may even be life threatening. In the majority of cases however a limp will have an innocent cause that can be easily identified and treated possibly requiring no more than simple reassurance. The true incidence of limp in children is unknown with no community based epidemiological studies. A UK teaching hospital reported an incidence of atraumatic limp of 1.8 per 1000 children presenting to the emergency department, equating to every 58th visit. In the UK shortfalls in the training of doctors involved in the assessment of children with musculoskeletal symptoms have been identified. In order to reduce delay in the diagnosis of potentially significant pathology professionals must be confident in the holistic assessment of the child. For example - in our own service we all too frequently receive late referrals for children with juvenile idiopathic arthritis because questions regarding symptoms beyond a limp have simply not been asked. This is devastating for patients, families and professionals alike. In this paper we will outline an approach to the evaluation of the limping child by a multi-disciplinary team, focussing on clinical assessment and investigations most likely to reveal the correct diagnosis. We begin with an overview of normal gait development and variations thereof.
Normal gait variants In-Toeing In-toeing or ‘pigeon toe’ arises as a result of pathology at three possible locations: femoral anteversion, internal tibial torsion and metatarsal adductus. Femoral anteversion (or medial femoral torsion) describes excessive inward rotation of the femur. At birth, approximately 40 of anteversion is present. It is typically most evident between the ages of 3e5 years due to increase in mobility and is more common in girls than boys. With skeletal maturity the angle gradually decreases and by adolescence it is approximately 10e15 . Surgery is only indicated if the child is 8 years of age and still presents with an angle greater than 50 degrees as excessive femoral anteversion can lead to patellar subluxation due to the femoral condylar alignment. Internal tibial torsion describes excessive medial rotation of the tibia. It is considered entirely normal at birth, however should spontaneously resolve between 18e24 months. It affects both sexes equally and although it can be unilateral, two thirds of patients present bilaterally. Treatment is only indicated if the thigh-foot angle is greater than -45 . Metatarsal adductus describes the medial displacement of the metatarsals and can be referred to as Skew or Banana foot. It presents from birth and approximately 85-90% spontaneously correct in the first year of life. It is associated with congenital dislocation of the hip. The deformity should be passively correctible with a normal hind foot and should not be confused with the more serious ‘club foot’ deformity. The cause of the deformity is thought to be intrauterine position.
Normal development of gait Normal gait is a complex mechanical process which is dependent on painless joints, adequate muscle power and an intact neurological
Ian Roberts BSc HONS HPC Physiotherapy Extended Scope Practitioner, Alder Hey Children’s Hospital NHS Foundation Trust. Gavin Cleary MBChB BSc HONS MSc FRCPCH Consultant Paediatric Rheumatologist, Alder Hey Children’s Hospital NHS Foundation Trust.
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SYMPOSIUM: SURGERY & ORTHOPAEDICS
Out-toeing Out-toeing is far less common than in-toeing. It is usually a packing defect due to fetal position with hips and knees flexed, ankles dorsiflexed and legs externally rotated. Like the more common ‘in-toe’ deformity the majority self correct in the first year of walking.
equinovarus (CETV). It can however present as idiopathic toe walking which can be more habitual in nature. Medically unexplainable gait Some children will present with limp that may not be explainable by organic pathology. In our practice we avoid the use of terms such as ‘‘hysterical’’ gait. Such gait patterns may mimic an organic impairment, however it is generally more theatrical in its presentation, and is frequently inconsistent. In our experience such gait patterns arise unconsciously as a result of a somatoform (conversion) disorder. This label must never be applied until exclusion of organic pathology and management is discussed further below.
Angular deformities (genu varum/valgum) As previously described genu varum (bow legged) and genu valgum (knock knee) are normal at certain stages of growth and is a passing trait which self corrects. This may be seen as a family trait. Pathological angular deformities are generally asymmetric, unilateral and can be painful and require appropriate investigation.
The surgical sieve for limping children Abnormal gait
To aid a structure in the evaluation of a limping child, readers are encouraged to consider using a surgical sieve approach. In no particular order there are many diagnostic or pathological processes that can result in a limp, shown in Table 1. This can be used as a framework during history taking and physical examination and will help guide subsequent investigations to maximise yield of positive information and minimise unnecessary and potential distressing tests. Utilising this approach it is possible to consider a large number of potential causes for limp in children, summarised in Table 2.
Limping is a deviation from the normal gait pattern expected for a child’s age resulting in an asymmetric walking pattern. Pathological gait patterns may guide the clinician to possible causes. It is however prudent to remember that multiple mechanisms can co-coexist e.g. in Perthes disease when there may be both antalgic and Trendelenburg characteristics to gait. Antalgic gait The antalgic limp is characterised by shortening of the stance phase on the affected side to avoid inducing pain and in extreme situations will result in complete refusal to mobilise.
History Ultimately there is no substitute for taking a detailed history from the child and carer focussing on the history of limp itself, but must include a detailed review of all systems, family history, medication and vaccination history, social and activity history including where appropriate a psychosocial history. Key points to focus on in the history are shown in Table 3, as these features will help to define the cause.
Circumduction gait Also referred to as ‘hemiplegic’ or ‘spastic’ gait, it is characterised when each step is initially rotated away from the body then towards it in a semi-circle motion. Typically, this is seen in children with cerebral palsy however may be caused by leg length discrepancy, stiff painful joints and in children with excessive genu valgum where the leg is swung outwards to avoid striking the planted limb.
Physical examination
Trendelenburg gait Caused by weakness of gluteus medius and minimus. During the stance phase the weakened muscles allow the contra-lateral side of the pelvis to tilt downwards. To compensate the trunk lurches to the weakened side in an attempt to maintain a level pelvis during gait. It is primarily seen in patients with hip pathology such as Perthes, slipped upper femoral epiphysis (SUFE) and developmental dysplasia of the hip (DDH). Bilateral Trendelenburg or a ‘waddling’ gait is associated with neuromuscular pathology such as muscular dystrophy.
After taking a careful history differential diagnoses can be further explored by physical examination. We suggest the priority is first to identify the gait pattern and seek any localising signs. To assess any suspected lower limb asymmetry a rotational profile is recommended to identify site of deformity. The following tests may be useful.
Surgical sieve headings for cause of limp in children List of diagnostic headings for limping in children C Congenital C Normal variant C Orthopaedic/Mechanical C Neoplastic C Inflammatory C Infective C Metabolic C Traumatic C Haematological C Iatrogenic C Medically unexplainable physical symptoms
High stepping gait A stepping gait is usually seen when a patient has lost the ability to actively dorsiflex the ankle. Due to the resulting foot drop a child will compensate by increasing hip and knee flexion during swing phase to improve ground clearance, stopping the toes dragging along the ground. It will be seen in any neurological condition affecting the common peroneal nerve including upper and lower neurone lesions. Equinus gait Equinus or ‘toe- walking’ gait is seen in any condition resulting in a shortening of the Achilles tendon or gastrocnemius muscle. It is common in children with cerebral palsy and congenital talipes
PAEDIATRICS AND CHILD HEALTH 20:5
Table 1
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SYMPOSIUM: SURGERY & ORTHOPAEDICS
Differential diagnosis of cause of limp with commonest gait pattern for each Differential diagnosis of limping in children Congenital Developmental dysplasia of the hip (DDH) Congenital talipes equinovarus (CTEV) Congenital short femur Skeletal dysplasias Multiple hereditary osteochondromata Mechanical/Orthopaedic Soft tissue injury including bruising, strains and foreign body Non accidental injury Skeletal fracture e including stress/overuse fracture Toddler’s fracture Apophysitis of tibial tuberosity (Osgood-Schlatter disease) or calcaneum (Sever’s disease) Chondromalacia patellae Tarsal coalitions Specific hip disorders Perthe’s disease Slipped upper femoral epiphysis Idiopathic chondrolysis Neoplastic/malignant disease Leukaemia/lymphoma Bone neoplasia (e.g. osteoid osteoma, osteoblastoma, and osteosarcoma.) Spinal cord tumour Neuroblastoma Langerhan’s cell histiocytosis Inflammatory Reactive arthritis including transient synovitis of the hip Juvenile idiopathic arthritis Myositis Other connective tissue disease (e.g. systemic vasculitis, systemic lupus erythematosus) Chronic recurrent multifocal osteomyelitis (CRMO) Synovitis Acne Pustulosis Hyperostosis Osteitis syndrome (SAPHO) Infection Skeletal sepsis including osteomyelitis and septic arthritis Discitis Soft tissue infection Abdominal sepsis including psoas abscess, appendicitis, peritonitis Inguinal lymphadenitis Metabolic Rickets Others Neurological and neuromuscular disease Haematological disease (e.g. haemophilia, sickle cell disease) Osteochondritis dissecans (knee, talus, metatarsal) Chronic pain syndromes (eg chronic regional pain syndrome Type I) Medically unexplained physical symptoms a
Commonest Gait Pattern T E C A,T,C A,T A A A A A A A A,T A,T A,T A A A A A A,T,Ca A,T,Ca A,T A,Ta A,Ta A,Ta A,T,Ca A A,T,C A,T A A T,C A A A,C,T,S,Ea A,C,T,S,E
A¼antalgic, C¼circumduction, T¼Trendelenberg, S¼stepping, E¼equinus, ¼depending on site involved.
Table 2
Foot progression angle This observational test determines if a child is in-toeing or outtoeing. It is the angle created by the foot against a straight line plotted in the direction a child is walking, however will not identify where the rotational deformity is originating.
PAEDIATRICS AND CHILD HEALTH 20:5
Craigs test (test for femoral torsion) With the child in prone position and with test knee flexed to 90 , the examiner palpates the posterior aspect of the greater trochanter then gently passively rotates the hip until greater trochanter is most prominent. The angle formed between vertical
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in leg length discrepancy from congenital hemimelia, developmental hip dysplasia and less common WILMS tumor affecting the ipsilateral kidney causing hemi-hypertrophy. A classical acquired cause is juvenile idiopathic arthritis.
Key points to establish when taking a history from a limping child Key points in the history when evaluating a limping child Onset e acute or chronic Painful or non painful Exacerbation by rest (‘‘gelling’’) e suggests inflammatory process e is there a history of joint swelling? Exacerbation by activity suggests biomechanical process e investigate sporting or other physical activities
Galeazzi Test With the child in supine bring the ankles to the buttocks with the knees flexed. A positive test is demonstrated when the knees are at different heights. ‘True’ leg length test In supine align pelvis by asking the child to adopt a bridging position by lifting knees and buttocks from bed. Measure from anterior superior iliac spine to medial malleolus and compare leg length.
Other constitutional symptoms e always consider as alerts (‘‘red flags’’) to potentially serious pathology C Fever C Night sweats C Night pain C Weight loss C Pallor or bruising C Abdominal pain C Malaise/lethargy C Weakness C Rash C Disability associated with symptoms
Specific disorders Musculoskeletal sepsis Generally bone and joint infection is of rapid onset and associated with systemic upset including fever, pallor, irritability and lethargy. Such signs may be masked in immunosuppressed children in whom a high index of suspicion is needed and this population need assessment in specialist centres. Unfortunately many children present out of hours making access to all imaging modalities difficult, and early clinical features may be difficult to distinguish from more benign conditions such as transient synovitis of the hip. Using logistic regression analysis, the absence of the following predictors: fever (>37 C), ESR > 35 mm/hr and duration of symptoms (>1, <5 days) enabled sepsis to be ruled out with 99% certainty in limping children. On the other hand, if sepsis is suspected peripheral blood cultures must be taken prior to empirical antibiotic therapy because of the likelihood of haematogenous seeding. The suspicion of septic arthritis should prompt microbiological analysis of both blood and synovial fluid. A septic joint should always be aspirated to confirm the diagnosis, allow microbiological studies and relieve pain. The management of musculoskeletal sepsis is reviewed in detail elsewhere. ESR and CRP may be useful in monitoring response to treatment. Special note should be made of discitis in toddlers with infants often adopting a distinctive prone position with extension of the lumbar spine for comfort.
Table 3
axis extending from tabletop and the longitudinal axis of the lower leg is measured. Normal variant range is þ/- 15 . Thigh foot angle (test for tibial torsion) Again the child is in prone with test knee flexed to 90 deg. An imaginary line is drawn down the centre of the thigh. The angle formed with the heel bisector is the thigh foot angle, in-toeing angles are normally given a negative value while out-toeing is positive. Thigh-foot angle is variable and age related however generally surgery would never be considered unless over 45 . Forefoot alignment This is a gross measurement to check for forefoot adductus. An imaginary line is drawn bisecting the heel up to the forefoot. Normally the line should pass between the second and third toes, hitting the fourth or fifth is indicative of adductus.
Juvenile Idiopathic Arthritis (JIA) This is a heterogeneous group of conditions characterised by arthritis of unknown cause in children below the age of 16 years. Classification of JIA is according to the onset pattern, namely: Oligoarthritis (4 joints in first 6 months). May subsequently ‘‘extend’’ and follow a polyarticular course Polyarthritis (5 or more joints in first 6 months). Subdivided by presence of rheumatoid factor Systemic arthritis (arthritis and quotidian fever, with at least one of: evanescent rash, lymphadenopathy, serositis, hepatosplenomegaly) Psoriatic arthritis Enthesitis related arthritis (frequently boys and associated with HLA B27). The child with active JIA of lower limb joint or SI joint will limp with an antalgic gait pattern. A frequent complication of
Hip assessment A thorough examination of the hip is essential in a limping child because hip pathology can often present as vague diffuse leg pain. In the majority of cases hip pathology is accompanied by an increase in synovial fluid production. Intra-capsular pressure is dependent on position of the hip and maximally increases in extension and internal rotation, resulting in a flexed and externally rotated posture of the hip. The most sensitive test for intra-articular pathology is prone internal rotation. With knees and ankles flexed, gently passively allow the ankles to fall away from the body, compare range of movement between legs. Leg length discrepancy Limb length should be assessed as a significant discrepancy will itself alter gait pattern. There are a variety of conditions resulting
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Pitfalls during investigation of limping children and potential solutions Pitfalls arising during assessment of limping children C Sterile synovial fluid in partially treated septic arthritis C Tuberculous skeletal disease C Classical clinical features of sepsis may be masked in immunosuppressed children C Medically unexplained physical symptoms are a diagnosis of exclusion but warrant specific management C Hip pathology may be referred to the knee C Labelling children with day time and disabling symptoms as ‘‘growing pains’’ C Certain patterns of injury are suspicious of non accidental injury C
Plain radiograph changes are frequently normal in early sepsis.
C
Peripheral blood film may not show blast cells in children with leukamia cells
C
Beware false positives such as antinuclear antibody and rheumatoid factor in children without an inflammatory phenotype
Solutions C Consider 16 S ribosomal RNA studies to search for bacterial product C Consider specific TB culture of synovial fluid and synovium C High index of suspicion and refer to specialist centre C
C C
Careful evaluation of psychosocial factors and referral to appropriate multidisciplinary team Examine and investigate the hip as appropriate Systematic approach to assessment
Is the history consistent with the signs of trauma? Seek advice from colleagues with relevant expertise. C Choose imaging modality according to clinical features and encourage clinician/radiologist discussion C Look for clues such as disproportionate pain and disability, thrombocytopenia and raised lactate dehydrogenase. Perform bone marrow examination if haematological malignancy suspected C Tailor investigations according to clinical features C
Table 4
uncontrolled chronic lower limb disease is leg length discrepancy resulting from stimulation of epiphyseal growth plates. This avoidable outcome can be prevented by early recognition and treatment with intra-articular steroid injection, the therapeutic agent of choice being triamcinolone hexacetonide. Children with synovitis of lower limb joints must have examination of all joints to avoid missing polyarthritis.
Health professionals must always be aware that physical, sexual or emotional abuse may be associated with unexplained physical symptoms, although such disclosures have been very rare within our own multidisciplinary approach to management.
Investigation The diagnostic yield from investigation will be improved if informed by a careful history and physical examination. For example immunological tests such as antinuclear antibody are only of relevance if the child has features of an inflammatory disorder, and indiscriminate testing runs the risk of false positive results that become difficult to interpret. Common pitfalls during investigation of limping children and potential solutions are shown in Table 4.
Warning: All children with JIA are at risk of potentially sight threatening uveitis and must be screened by ophthalmology services. Screening guidelines are available at www.bspar.org.uk In contrast to inflammatory disorders, limping associated with mechanical problems, including joint hypermobility syndromes, is generally exacerbated by exertion and relieved by rest. However it must be noted that limping associated with mechanical problems may be present for prolonged periods such as into the next day, particularly if the exertion has been strenuous. Idiopathic nocturnal pain (‘‘growing pain’’) may have a profound effect on whole families and be associated with significant distress, but remains a diagnosis of exclusion.
Laboratory investigations A baseline screen of full blood count (FBC), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) should be performed in all children with acute onset atraumatic limp. If septic arthritis is considered blood culture and joint aspiration prior to antibiotics is gold standard. Recognising joint aspiration may require general anaesthetic in younger children, blood culture must be taken. Culture from bone may have highest yield of positive culture in osteomyelitis. Other laboratory investigations should follow a logical sequence according to the clinical features. It is impossible to be exhaustive and the authors recommend advice from appropriate specialists depending on likely underlying diagnosis.
Medically unexplainable causes of limping Limping that cannot be explained by physiological process despite assessments outlined above is, in our experience, becoming more prevalent and presents particular challenges to health professionals. Disability is frequently significant, and symptoms in other organ systems such as abdominal pain, headache and fatigue may be present. The gait may be bizarre and inconsistent, with discrepancy between active and passive movements. However dismissing such symptoms as ‘‘hysterical’’ or ‘‘psychosomatic’’ is unhelpful, and a multidisciplinary approach utilising a biopsychosocial model is recommended.
PAEDIATRICS AND CHILD HEALTH 20:5
Conclusion Limping is common in children. In the majority of cases the cause is benign and self-limiting, but there are a broad range of potential
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Petty RE, Southwood TR, Manners P, et al. International League of Associations for Rheumatology classification of juvenile idiopathic arthritis: second revision, Edmonton, 2001. J Rheumatol 2004 Feb; 31: 390e2. Rosey AL, Abachin E, Quesnes G, et al. Development of a broad-range 16S rDNA real time PCR for the diagnosis of septic arthritis in children. J Microbial Methods 2007; 68: 88e93. Zulian F, Martini G, Gobber D, Plebani M, Zacchello F, Manners P. Triamcinolone acetonide and hexacetonide intra-articular treatment of symmetrical joints in juvenile idiopathic arthritis: a double-blind trial. Rheumatology (Oxford) 2004 Oct; 43: 1288e91.
pathological causes. In order to determine the cause of limping, it is necessary to understand the mechanisms of normal gait and its variants and a holistic approach to assessment of the child is essential.A
FURTHER READING Calvert P, Jureidini J. Restrained rehabilitation: an approach to children and adolescents with unexplained signs and symptoms. Arch Dis Child 2003; 88: 399e402. Davidson J, Cleary AG, Bruce C. Disorders of bones, joints and connective tissues. In: McIntosh N, Helms P, Smyth R, Logan S editors. Forfar and Arneil’s textbook of paediatrics. 7th rd. 2008;1385e1446. Delaney RA, Lenehan B, O’Sullivan L, McGuiness AJ, Street JT. The limping child: an algorithm to outrule musculoskeletal sepsis. Ir J Med Sci 2007; 176: 181e7. Fischer SU, Beattie TF. The limping child: epidemiology, assessment and outcome. J Bone Joint Surg [Br] 1999; 81-B: 1029e34. Halliwell P, Monsell F. Growing pains: a diagnosis of exclusion. Practitioner 2001; 245: 620e3. Hartwig NG. How to treat acute musculoskeletal infections in children. Adv Exp Med Biol 2006; 582: 191e200. Jandial S, Rapley T, Foster H. Current teaching of paediatric musculoskeletal medicine within UK medical schools - a need for change. Rheumatology (Oxford) 2009; 48: 587e90.
PAEDIATRICS AND CHILD HEALTH 20:5
Clinical practice points C
C
C
C
200
This review will help the reader understand normal gait development in children and identify abnormal gait patterns Limping children must always have a holistic assessment, as limp may be associated with systemic pathology Undue diagnostic delay may increase morbidity or even mortality Not all children with limp have medically explainable pathology and will require psychosocial assessment after careful exclusion of organic disease.
Ó 2009 Elsevier Ltd. All rights reserved.
Evaluation of the limping child
system. It should be smooth, rhythmical and energy efficient. Children’s gait patterns differ greatly from adults and it’s only by the age of 3e4 years that gait exhibits adult type characteristics. By 7 years the child’s gait is nearly identical to that of an adult. Children typically start walking between 10e18 months of age. At this stage it is common to see bowing (genu varum)of the legs. Children stand with a wide base of support to improve stability. An increase in lumbar lordosis is present due to lack of abdominal tone however this may also be a compensatory mechanism by placing the lumbar spine ‘facet’ joints into a closed pack position and hence improving stability by increasing afferent input. Gait is slow although ironically, cadence (number of steps per minute) is very high due to leg length and poor balance. As the child develops so does lower limb alignment, by 2e3 years of age typically the lower limb shows a ‘knock knee’ posture (genu valgum). They are now able to stand on one leg for longer due to improving hip abductor strength and balance. Cadence is also helped by an increasing leg length. At 4e6 years of age the majority of children have developed a medial longitudinal arch, however they still may present with a flexible ‘pes planus’ on weight bearing due to hypermobility and poor intrinsic muscle function. A congenital flat foot is not dependent on weight-bearing and is present at all times. It is also at this stage that the lower limb will begin to straighten into normal alignment. As muscle power and co-ordination improve the child is able to balance for longer on one leg and the majority of children are able to hop by 6e7 years of age.
Ian Roberts Gavin Cleary
Abstract Limping in children is common and may arise from a spectrum of disorders ranging from normal variations in gait development, through to potentially life threatening systemic disease. In this review we take the reader through the normal development of gait, then discuss normal variants of gait in order to identify pathological gait patterns. We aim to provide a framework for the holistic clinical assessment of the limping child and review in more detail some of the commoner diseases associated with limping. Finally some of the commoner pitfalls to establishing a correct diagnosis are presented along with suggestions that may help to improve the diagnostic yield.
Keywords Abnormal gait; Children; Limping
Introduction Accepting a limp as normal in a child risks failure to diagnose potentially significant pathology. Certain pathology may even be life threatening. In the majority of cases however a limp will have an innocent cause that can be easily identified and treated possibly requiring no more than simple reassurance. The true incidence of limp in children is unknown with no community based epidemiological studies. A UK teaching hospital reported an incidence of atraumatic limp of 1.8 per 1000 children presenting to the emergency department, equating to every 58th visit. In the UK shortfalls in the training of doctors involved in the assessment of children with musculoskeletal symptoms have been identified. In order to reduce delay in the diagnosis of potentially significant pathology professionals must be confident in the holistic assessment of the child. For example - in our own service we all too frequently receive late referrals for children with juvenile idiopathic arthritis because questions regarding symptoms beyond a limp have simply not been asked. This is devastating for patients, families and professionals alike. In this paper we will outline an approach to the evaluation of the limping child by a multi-disciplinary team, focussing on clinical assessment and investigations most likely to reveal the correct diagnosis. We begin with an overview of normal gait development and variations thereof.
Normal gait variants In-Toeing In-toeing or ‘pigeon toe’ arises as a result of pathology at three possible locations: femoral anteversion, internal tibial torsion and metatarsal adductus. Femoral anteversion (or medial femoral torsion) describes excessive inward rotation of the femur. At birth, approximately 40 of anteversion is present. It is typically most evident between the ages of 3e5 years due to increase in mobility and is more common in girls than boys. With skeletal maturity the angle gradually decreases and by adolescence it is approximately 10e15 . Surgery is only indicated if the child is 8 years of age and still presents with an angle greater than 50 degrees as excessive femoral anteversion can lead to patellar subluxation due to the femoral condylar alignment. Internal tibial torsion describes excessive medial rotation of the tibia. It is considered entirely normal at birth, however should spontaneously resolve between 18e24 months. It affects both sexes equally and although it can be unilateral, two thirds of patients present bilaterally. Treatment is only indicated if the thigh-foot angle is greater than -45 . Metatarsal adductus describes the medial displacement of the metatarsals and can be referred to as Skew or Banana foot. It presents from birth and approximately 85-90% spontaneously correct in the first year of life. It is associated with congenital dislocation of the hip. The deformity should be passively correctible with a normal hind foot and should not be confused with the more serious ‘club foot’ deformity. The cause of the deformity is thought to be intrauterine position.
Normal development of gait Normal gait is a complex mechanical process which is dependent on painless joints, adequate muscle power and an intact neurological
Ian Roberts BSc HONS HPC Physiotherapy Extended Scope Practitioner, Alder Hey Children’s Hospital NHS Foundation Trust. Gavin Cleary MBChB BSc HONS MSc FRCPCH Consultant Paediatric Rheumatologist, Alder Hey Children’s Hospital NHS Foundation Trust.
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SYMPOSIUM: SURGERY & ORTHOPAEDICS
Out-toeing Out-toeing is far less common than in-toeing. It is usually a packing defect due to fetal position with hips and knees flexed, ankles dorsiflexed and legs externally rotated. Like the more common ‘in-toe’ deformity the majority self correct in the first year of walking.
equinovarus (CETV). It can however present as idiopathic toe walking which can be more habitual in nature. Medically unexplainable gait Some children will present with limp that may not be explainable by organic pathology. In our practice we avoid the use of terms such as ‘‘hysterical’’ gait. Such gait patterns may mimic an organic impairment, however it is generally more theatrical in its presentation, and is frequently inconsistent. In our experience such gait patterns arise unconsciously as a result of a somatoform (conversion) disorder. This label must never be applied until exclusion of organic pathology and management is discussed further below.
Angular deformities (genu varum/valgum) As previously described genu varum (bow legged) and genu valgum (knock knee) are normal at certain stages of growth and is a passing trait which self corrects. This may be seen as a family trait. Pathological angular deformities are generally asymmetric, unilateral and can be painful and require appropriate investigation.
The surgical sieve for limping children Abnormal gait
To aid a structure in the evaluation of a limping child, readers are encouraged to consider using a surgical sieve approach. In no particular order there are many diagnostic or pathological processes that can result in a limp, shown in Table 1. This can be used as a framework during history taking and physical examination and will help guide subsequent investigations to maximise yield of positive information and minimise unnecessary and potential distressing tests. Utilising this approach it is possible to consider a large number of potential causes for limp in children, summarised in Table 2.
Limping is a deviation from the normal gait pattern expected for a child’s age resulting in an asymmetric walking pattern. Pathological gait patterns may guide the clinician to possible causes. It is however prudent to remember that multiple mechanisms can co-coexist e.g. in Perthes disease when there may be both antalgic and Trendelenburg characteristics to gait. Antalgic gait The antalgic limp is characterised by shortening of the stance phase on the affected side to avoid inducing pain and in extreme situations will result in complete refusal to mobilise.
History Ultimately there is no substitute for taking a detailed history from the child and carer focussing on the history of limp itself, but must include a detailed review of all systems, family history, medication and vaccination history, social and activity history including where appropriate a psychosocial history. Key points to focus on in the history are shown in Table 3, as these features will help to define the cause.
Circumduction gait Also referred to as ‘hemiplegic’ or ‘spastic’ gait, it is characterised when each step is initially rotated away from the body then towards it in a semi-circle motion. Typically, this is seen in children with cerebral palsy however may be caused by leg length discrepancy, stiff painful joints and in children with excessive genu valgum where the leg is swung outwards to avoid striking the planted limb.
Physical examination
Trendelenburg gait Caused by weakness of gluteus medius and minimus. During the stance phase the weakened muscles allow the contra-lateral side of the pelvis to tilt downwards. To compensate the trunk lurches to the weakened side in an attempt to maintain a level pelvis during gait. It is primarily seen in patients with hip pathology such as Perthes, slipped upper femoral epiphysis (SUFE) and developmental dysplasia of the hip (DDH). Bilateral Trendelenburg or a ‘waddling’ gait is associated with neuromuscular pathology such as muscular dystrophy.
After taking a careful history differential diagnoses can be further explored by physical examination. We suggest the priority is first to identify the gait pattern and seek any localising signs. To assess any suspected lower limb asymmetry a rotational profile is recommended to identify site of deformity. The following tests may be useful.
Surgical sieve headings for cause of limp in children List of diagnostic headings for limping in children C Congenital C Normal variant C Orthopaedic/Mechanical C Neoplastic C Inflammatory C Infective C Metabolic C Traumatic C Haematological C Iatrogenic C Medically unexplainable physical symptoms
High stepping gait A stepping gait is usually seen when a patient has lost the ability to actively dorsiflex the ankle. Due to the resulting foot drop a child will compensate by increasing hip and knee flexion during swing phase to improve ground clearance, stopping the toes dragging along the ground. It will be seen in any neurological condition affecting the common peroneal nerve including upper and lower neurone lesions. Equinus gait Equinus or ‘toe- walking’ gait is seen in any condition resulting in a shortening of the Achilles tendon or gastrocnemius muscle. It is common in children with cerebral palsy and congenital talipes
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Table 1
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Differential diagnosis of cause of limp with commonest gait pattern for each Differential diagnosis of limping in children Congenital Developmental dysplasia of the hip (DDH) Congenital talipes equinovarus (CTEV) Congenital short femur Skeletal dysplasias Multiple hereditary osteochondromata Mechanical/Orthopaedic Soft tissue injury including bruising, strains and foreign body Non accidental injury Skeletal fracture e including stress/overuse fracture Toddler’s fracture Apophysitis of tibial tuberosity (Osgood-Schlatter disease) or calcaneum (Sever’s disease) Chondromalacia patellae Tarsal coalitions Specific hip disorders Perthe’s disease Slipped upper femoral epiphysis Idiopathic chondrolysis Neoplastic/malignant disease Leukaemia/lymphoma Bone neoplasia (e.g. osteoid osteoma, osteoblastoma, and osteosarcoma.) Spinal cord tumour Neuroblastoma Langerhan’s cell histiocytosis Inflammatory Reactive arthritis including transient synovitis of the hip Juvenile idiopathic arthritis Myositis Other connective tissue disease (e.g. systemic vasculitis, systemic lupus erythematosus) Chronic recurrent multifocal osteomyelitis (CRMO) Synovitis Acne Pustulosis Hyperostosis Osteitis syndrome (SAPHO) Infection Skeletal sepsis including osteomyelitis and septic arthritis Discitis Soft tissue infection Abdominal sepsis including psoas abscess, appendicitis, peritonitis Inguinal lymphadenitis Metabolic Rickets Others Neurological and neuromuscular disease Haematological disease (e.g. haemophilia, sickle cell disease) Osteochondritis dissecans (knee, talus, metatarsal) Chronic pain syndromes (eg chronic regional pain syndrome Type I) Medically unexplained physical symptoms a
Commonest Gait Pattern T E C A,T,C A,T A A A A A A A A,T A,T A,T A A A A A A,T,Ca A,T,Ca A,T A,Ta A,Ta A,Ta A,T,Ca A A,T,C A,T A A T,C A A A,C,T,S,Ea A,C,T,S,E
A¼antalgic, C¼circumduction, T¼Trendelenberg, S¼stepping, E¼equinus, ¼depending on site involved.
Table 2
Foot progression angle This observational test determines if a child is in-toeing or outtoeing. It is the angle created by the foot against a straight line plotted in the direction a child is walking, however will not identify where the rotational deformity is originating.
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Craigs test (test for femoral torsion) With the child in prone position and with test knee flexed to 90 , the examiner palpates the posterior aspect of the greater trochanter then gently passively rotates the hip until greater trochanter is most prominent. The angle formed between vertical
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in leg length discrepancy from congenital hemimelia, developmental hip dysplasia and less common WILMS tumor affecting the ipsilateral kidney causing hemi-hypertrophy. A classical acquired cause is juvenile idiopathic arthritis.
Key points to establish when taking a history from a limping child Key points in the history when evaluating a limping child Onset e acute or chronic Painful or non painful Exacerbation by rest (‘‘gelling’’) e suggests inflammatory process e is there a history of joint swelling? Exacerbation by activity suggests biomechanical process e investigate sporting or other physical activities
Galeazzi Test With the child in supine bring the ankles to the buttocks with the knees flexed. A positive test is demonstrated when the knees are at different heights. ‘True’ leg length test In supine align pelvis by asking the child to adopt a bridging position by lifting knees and buttocks from bed. Measure from anterior superior iliac spine to medial malleolus and compare leg length.
Other constitutional symptoms e always consider as alerts (‘‘red flags’’) to potentially serious pathology C Fever C Night sweats C Night pain C Weight loss C Pallor or bruising C Abdominal pain C Malaise/lethargy C Weakness C Rash C Disability associated with symptoms
Specific disorders Musculoskeletal sepsis Generally bone and joint infection is of rapid onset and associated with systemic upset including fever, pallor, irritability and lethargy. Such signs may be masked in immunosuppressed children in whom a high index of suspicion is needed and this population need assessment in specialist centres. Unfortunately many children present out of hours making access to all imaging modalities difficult, and early clinical features may be difficult to distinguish from more benign conditions such as transient synovitis of the hip. Using logistic regression analysis, the absence of the following predictors: fever (>37 C), ESR > 35 mm/hr and duration of symptoms (>1, <5 days) enabled sepsis to be ruled out with 99% certainty in limping children. On the other hand, if sepsis is suspected peripheral blood cultures must be taken prior to empirical antibiotic therapy because of the likelihood of haematogenous seeding. The suspicion of septic arthritis should prompt microbiological analysis of both blood and synovial fluid. A septic joint should always be aspirated to confirm the diagnosis, allow microbiological studies and relieve pain. The management of musculoskeletal sepsis is reviewed in detail elsewhere. ESR and CRP may be useful in monitoring response to treatment. Special note should be made of discitis in toddlers with infants often adopting a distinctive prone position with extension of the lumbar spine for comfort.
Table 3
axis extending from tabletop and the longitudinal axis of the lower leg is measured. Normal variant range is þ/- 15 . Thigh foot angle (test for tibial torsion) Again the child is in prone with test knee flexed to 90 deg. An imaginary line is drawn down the centre of the thigh. The angle formed with the heel bisector is the thigh foot angle, in-toeing angles are normally given a negative value while out-toeing is positive. Thigh-foot angle is variable and age related however generally surgery would never be considered unless over 45 . Forefoot alignment This is a gross measurement to check for forefoot adductus. An imaginary line is drawn bisecting the heel up to the forefoot. Normally the line should pass between the second and third toes, hitting the fourth or fifth is indicative of adductus.
Juvenile Idiopathic Arthritis (JIA) This is a heterogeneous group of conditions characterised by arthritis of unknown cause in children below the age of 16 years. Classification of JIA is according to the onset pattern, namely: Oligoarthritis (4 joints in first 6 months). May subsequently ‘‘extend’’ and follow a polyarticular course Polyarthritis (5 or more joints in first 6 months). Subdivided by presence of rheumatoid factor Systemic arthritis (arthritis and quotidian fever, with at least one of: evanescent rash, lymphadenopathy, serositis, hepatosplenomegaly) Psoriatic arthritis Enthesitis related arthritis (frequently boys and associated with HLA B27). The child with active JIA of lower limb joint or SI joint will limp with an antalgic gait pattern. A frequent complication of
Hip assessment A thorough examination of the hip is essential in a limping child because hip pathology can often present as vague diffuse leg pain. In the majority of cases hip pathology is accompanied by an increase in synovial fluid production. Intra-capsular pressure is dependent on position of the hip and maximally increases in extension and internal rotation, resulting in a flexed and externally rotated posture of the hip. The most sensitive test for intra-articular pathology is prone internal rotation. With knees and ankles flexed, gently passively allow the ankles to fall away from the body, compare range of movement between legs. Leg length discrepancy Limb length should be assessed as a significant discrepancy will itself alter gait pattern. There are a variety of conditions resulting
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Pitfalls during investigation of limping children and potential solutions Pitfalls arising during assessment of limping children C Sterile synovial fluid in partially treated septic arthritis C Tuberculous skeletal disease C Classical clinical features of sepsis may be masked in immunosuppressed children C Medically unexplained physical symptoms are a diagnosis of exclusion but warrant specific management C Hip pathology may be referred to the knee C Labelling children with day time and disabling symptoms as ‘‘growing pains’’ C Certain patterns of injury are suspicious of non accidental injury C
Plain radiograph changes are frequently normal in early sepsis.
C
Peripheral blood film may not show blast cells in children with leukamia cells
C
Beware false positives such as antinuclear antibody and rheumatoid factor in children without an inflammatory phenotype
Solutions C Consider 16 S ribosomal RNA studies to search for bacterial product C Consider specific TB culture of synovial fluid and synovium C High index of suspicion and refer to specialist centre C
C C
Careful evaluation of psychosocial factors and referral to appropriate multidisciplinary team Examine and investigate the hip as appropriate Systematic approach to assessment
Is the history consistent with the signs of trauma? Seek advice from colleagues with relevant expertise. C Choose imaging modality according to clinical features and encourage clinician/radiologist discussion C Look for clues such as disproportionate pain and disability, thrombocytopenia and raised lactate dehydrogenase. Perform bone marrow examination if haematological malignancy suspected C Tailor investigations according to clinical features C
Table 4
uncontrolled chronic lower limb disease is leg length discrepancy resulting from stimulation of epiphyseal growth plates. This avoidable outcome can be prevented by early recognition and treatment with intra-articular steroid injection, the therapeutic agent of choice being triamcinolone hexacetonide. Children with synovitis of lower limb joints must have examination of all joints to avoid missing polyarthritis.
Health professionals must always be aware that physical, sexual or emotional abuse may be associated with unexplained physical symptoms, although such disclosures have been very rare within our own multidisciplinary approach to management.
Investigation The diagnostic yield from investigation will be improved if informed by a careful history and physical examination. For example immunological tests such as antinuclear antibody are only of relevance if the child has features of an inflammatory disorder, and indiscriminate testing runs the risk of false positive results that become difficult to interpret. Common pitfalls during investigation of limping children and potential solutions are shown in Table 4.
Warning: All children with JIA are at risk of potentially sight threatening uveitis and must be screened by ophthalmology services. Screening guidelines are available at www.bspar.org.uk In contrast to inflammatory disorders, limping associated with mechanical problems, including joint hypermobility syndromes, is generally exacerbated by exertion and relieved by rest. However it must be noted that limping associated with mechanical problems may be present for prolonged periods such as into the next day, particularly if the exertion has been strenuous. Idiopathic nocturnal pain (‘‘growing pain’’) may have a profound effect on whole families and be associated with significant distress, but remains a diagnosis of exclusion.
Laboratory investigations A baseline screen of full blood count (FBC), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) should be performed in all children with acute onset atraumatic limp. If septic arthritis is considered blood culture and joint aspiration prior to antibiotics is gold standard. Recognising joint aspiration may require general anaesthetic in younger children, blood culture must be taken. Culture from bone may have highest yield of positive culture in osteomyelitis. Other laboratory investigations should follow a logical sequence according to the clinical features. It is impossible to be exhaustive and the authors recommend advice from appropriate specialists depending on likely underlying diagnosis.
Medically unexplainable causes of limping Limping that cannot be explained by physiological process despite assessments outlined above is, in our experience, becoming more prevalent and presents particular challenges to health professionals. Disability is frequently significant, and symptoms in other organ systems such as abdominal pain, headache and fatigue may be present. The gait may be bizarre and inconsistent, with discrepancy between active and passive movements. However dismissing such symptoms as ‘‘hysterical’’ or ‘‘psychosomatic’’ is unhelpful, and a multidisciplinary approach utilising a biopsychosocial model is recommended.
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Conclusion Limping is common in children. In the majority of cases the cause is benign and self-limiting, but there are a broad range of potential
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Petty RE, Southwood TR, Manners P, et al. International League of Associations for Rheumatology classification of juvenile idiopathic arthritis: second revision, Edmonton, 2001. J Rheumatol 2004 Feb; 31: 390e2. Rosey AL, Abachin E, Quesnes G, et al. Development of a broad-range 16S rDNA real time PCR for the diagnosis of septic arthritis in children. J Microbial Methods 2007; 68: 88e93. Zulian F, Martini G, Gobber D, Plebani M, Zacchello F, Manners P. Triamcinolone acetonide and hexacetonide intra-articular treatment of symmetrical joints in juvenile idiopathic arthritis: a double-blind trial. Rheumatology (Oxford) 2004 Oct; 43: 1288e91.
pathological causes. In order to determine the cause of limping, it is necessary to understand the mechanisms of normal gait and its variants and a holistic approach to assessment of the child is essential.A
FURTHER READING Calvert P, Jureidini J. Restrained rehabilitation: an approach to children and adolescents with unexplained signs and symptoms. Arch Dis Child 2003; 88: 399e402. Davidson J, Cleary AG, Bruce C. Disorders of bones, joints and connective tissues. In: McIntosh N, Helms P, Smyth R, Logan S editors. Forfar and Arneil’s textbook of paediatrics. 7th rd. 2008;1385e1446. Delaney RA, Lenehan B, O’Sullivan L, McGuiness AJ, Street JT. The limping child: an algorithm to outrule musculoskeletal sepsis. Ir J Med Sci 2007; 176: 181e7. Fischer SU, Beattie TF. The limping child: epidemiology, assessment and outcome. J Bone Joint Surg [Br] 1999; 81-B: 1029e34. Halliwell P, Monsell F. Growing pains: a diagnosis of exclusion. Practitioner 2001; 245: 620e3. Hartwig NG. How to treat acute musculoskeletal infections in children. Adv Exp Med Biol 2006; 582: 191e200. Jandial S, Rapley T, Foster H. Current teaching of paediatric musculoskeletal medicine within UK medical schools - a need for change. Rheumatology (Oxford) 2009; 48: 587e90.
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Clinical practice points C
C
C
C
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This review will help the reader understand normal gait development in children and identify abnormal gait patterns Limping children must always have a holistic assessment, as limp may be associated with systemic pathology Undue diagnostic delay may increase morbidity or even mortality Not all children with limp have medically explainable pathology and will require psychosocial assessment after careful exclusion of organic disease.
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