Evaluation of the Child with Acute Limp
Bruce Minnes MD, FRCPCStaff Physician and Assistant Professor,
Division of Paediatric Emergency MedicineChief Medical Editor, AboutKidsHealth
SickKids and The University of Toronto
[email protected]@AesklepianBruce
Objectives
After this talk, participants will be able to:
• Identify common causes of acute limp in children
• Develop appropriate differential diagnoses based on age, clinical findings and circumstance
• Develop an approach to investigating patients with an acute limp
Limp
Abnormal gait pattern:• Pain• Weakness• Deformity
Antalgic: pain shortened stance phase on affected side
Development of gait: mature, rhythmic, reproducible gait cycle after age 7
History
• Age• Interactions child/family• Consistency (? Non-accidental injury)• Mechanism (acute or remote)• Associated symptoms: fever, rash, pallor,
bruising, weight loss• Limp: apparent site (referred pain), duration,
severity, effect on activity, painful or painless
Examination - pGALS
paediatric “Gait, Arms, Legs, Spine” examination
• Screening questions: Pain or stiffness? Location?• Gait/general: temperature, walking pattern regular,
on toes, on heels, standing and bending• Arms: not applicable• Legs: swelling, tenderness, deformities, effusions,
entry points, active/passice ROM, laxity, hip IR/ER• Spine: position, ROM, tenderness, overlying
abnormalities
Examination: Look, Feel, Move
• Look: fever, habitus, colour/rashes, entry points, stand, gait, positions (spine, limb), swelling, deformities, muscle bulk
• Feel: focal/general tenderness, can patient localize pain, warmth, effusions
• Move: walk, jump, hop, gait pattern, joint ROMs, back/hips/knees/ankles/feet
• Other: abdomen, scrotum/testes, back
Limp – Key Diagnoses
• Toddler’s fracture• Non-accidental injury (NAI)• Transient synovitis• Septic arthritis/Osteomyelitis• Slipped Capital Femoral Epiphysis (SCFE)• Legg Perthes’ Disease
Toddler’s Fracture
• Subtle undisplaced spiral fracture of tibia• Preschoolers• Sudden twist• History of injury may be absent• Tenderness over tibial shaft• Radiographs: may be subtle, absent, require
oblique views or nuclear medicine scan• Immobilize and arrange follow-up
Non-Accidental Injury
• Injury pattern vague or inconsistent with history of mechanism or developmental stage
• Recurrent minor fractures• Other unrelated fractures• Variable stages of healing• Fracture pattern: Metaphyseal (bucket-
handle) fracures in long bones
Transient Synovitis
• Most common cause of atraumatic limp in children
• Boys• Ages 4 – 8 years• Self limiting• ? Post viral• Hip effusion and exclusion of more important
causes
Septic Arthritis
• Infection of synovium and joint space• May originate from haematogenous spread
(Staphylococcus aureus), osteomylelitis of metaphysis or epiphysis
• Hip, shoulder, ankle, elbow, knee• Requires urgent surgical washout and
intravenous antibiotics to prevent/minimize joint destruction and growth arrest
Septic Arthritis: Kocher’s criteria
Predictive factors:
•Fever > 38.5 degrees•Inability to bear weight•ESR > 40 mm/hr•WBC > 12x109 /l
Probability of septic arthritis:•None: <0.2%•One: 3%•Two: 40%•Three: 93.1%•Four: 99.6%
Kocher, MS et al. J Bone Joint Surg Am. 1999. 81:1662-70
Septic Arthritis in Children• Most common organisms: S. aureus and Group A
streptococcus• Typical signs/symptoms may be absent,
particularly in neonates and infants• CRP, ESR added to Kocher’s criteria useful• Recommend early initiation of antibiotics• Length of treatment based on clinical and
serologic response• Arthrotomy, arthroscopy usually recommended• Multidisciplinary approach
Kang, S-N et al. J Bone Joint Surg (Br) 2009. 91B:1127-33
Slipped Capital Femoral Epiphysis
• Children over 10 years• More common in boys and overweight
patients, hypothyroid, GH deficiency• Displacement of epiphysis relative to
metaphysis (Kline’s Line)• Knee pain• Early fixation improves outcome• Xrays: Hips AP and frog-leg (lateral)
Legg Perthe’s Disease
• Idiopathic avascular necrosis of the femoral head
• Ages 4 – 8 years, usually boys• Xray: Hips AP. Lateral sometimes helps.• Sclerosis, fragmentation, irregularity,
flattening of femoral epiphysis• Persistent limp (contrast to transient
synovitis)
ASIS Avulsion
• Larger forces – MVC or sport-related• Inability to bear weight from pain• Extremely tender over ASIS, reduced active
hip flexion and pain on passive extension• Non-weight bearing and analgesics with
orthopaedic follow up
Limp – Red Flags
• Age under 3 years• Inability to bear weight• Fever• Systemic illness• Older child with painful or restricted hip
movement
Acute Limp - Summary• Non-traumatic limp is a common presenting
problem in children and adolescents• Age is key in identifying differential
considerations• Hip is most common site of pathology• Delayed diagnosis may worsen outcome
(osteomyelitis, septic joint, SCFE)• Transient synovitis & septic
arthritis/osteomyelitis may be hard to differentiate