Background
- A limp is defined as an asymmetric gait and is a deviation from a normal age-appropriate gait pattern
- Most presentations are benign and do not require investigations, however serious pathology must be considered
Key points
- A thorough gait assessment, examination of the lower limbs, spine and other relevant body systems is essential to accurately localise the source
- A patient who cannot put any weight on the affected limb cannot be discharged without a clear diagnosis
- Severe localised joint pain is concerning for septic arthritis
Approach
Assessment
| Duration | Systemic Features | Location | Range of Motion | Imaging | |
| Developmental Dysplasia of the hip | Weeks | None | Bilateral in 20% | Dislocatable hip (<3 months). Limited hip abduction (<1 year). Toe walking (>1 year) | X-ray: AP/ frog leg lateral view | 
| Transient Synovitis | Days | Possible recent viral infection | Unilateral | Limited internal rotation | Not usually required | 
| Septic Arthritis (Hip) | Days | Fever Chills, rigors | Severe localised joint pain | Held in external rotation, abduction and flexion | US. Further imaging and joint aspiration in conjunction with Orthopaedics | 
| Duration | Location | Range of Motion | Leg length Disparity | Imaging | |
| Perthes | Weeks | Bilateral in 10% | Limited abduction and internal rotation | Late finding | X-ray: AP/ frog leg lateral view | 
| SUFE | Acute or chronic | Bilateral in 30%. Vague pain in groin, hip or knee | Externally rotated leg | Yes | X-ray: AP/frog leg lateral view | 
| Septic Arthritis (Hip) | Days | Fever, chills, rigors | Severe localised joint pain | Held in external rotation, abduction and flexion | US. Further imaging and joint aspiration in conjunction with Ortho. | 
Other pathologies considered
- Malignancy – solid or haematological
- Fracture/Sprain
- Neuromuscular disease – cerebral palsy, muscular dystrophy
- Neurological - ataxia, guillain-barre, transverse myelitis, stroke
- Rheumatological/Immunological – HSP, vasculitis, juvenile RA, discitis, osteomyelitis
- Non MSK – appendicitis, testicular or ovarian torsion, Psoas Abscess
* Appendix
| No. of Factors | Modified Kocher Criteria | Kocher Criteria | 
| 0 | 17 | 0.2 | 
| 1 | 37 | 3 | 
| 2 | 62 | 40 | 
| 3 | 83 | 93 | 
| 4 | 93 | 99 | 
| 5 | 98 | 
Factors: Temp >38.5°C, WBC >12 x109/L, ESR >40 mm/Hr, refusal to weight bear ± CRP >20 mg/mL (if using modified Kocher criteria)
Discharge Criteria
Cause of limp identified and managed/referred appropriately or
- No red flags identified
- Patient ambulating with mild/no discomfort with simple analgesia
- Patient information sheet provided
References
- Kocher MS, Zurakowski D, Kasser JR. Differentiating Between Septic Arthritis and Transient Synovitis of the Hip in Children. The Journal of Bone & Joint Surgery. 1999 Dec;81(12):1662–70
- Caird MS, Flynn JM, Leung YL, Millman JE, DʼItalia JG, Dormans JP. Factors Distinguishing Septic Arthritis from Transient Synovitis of the Hip in Children. The Journal of Bone & Joint Surgery. 2006 Jun;88(6):1251–7
- RCH Limp Guidelines
- NICE Limp Guidelines
- Andrew Tagg, The child with a limp, Don't Forget the Bubbles, 2020
- Queensland Paediatric Flowchart