Limping in Children — Acute & Chronic Presentation
Ages 0–16 · Differential diagnosis, safety exclusion, investigation & management pathway
Progress0 / 9
The full reasoning pathway — the limping child needs septic arthritis and non-accidental injury excluded first, then an age-based differential from transient synovitis to malignancy. Manage and safety-net.StartDecisionInvestigateActionReferStop / Admit
Well child, post-viral, low-grade; settles with rest/analgesia — diagnosis of exclusion.
Age-specific hip
Structural
DDH (infant), Perthes (4–8y), SUFE (adolescent, often overweight) → orthopaedics.
Reactive / other
Consider
Reactive arthritis, JIA, fracture, malignancy.
Step 6 · ReferEscalation
Emergency septic arthritis / suspected NAI / malignancy. Orthopaedics Perthes/SUFE/DDH; SUFE needs urgent referral and non-weight-bearing.
Step 8 · management & family advice
Step 8 · Management & family adviceFor benign transient synovitis
Transient synovitis (well child, exclusion diagnosis): rest, simple analgesia/ibuprofen, reduced activity — usually settles within ~1–2 weeks. Give parents clear written safety-net advice and a planned review. Encourage normal mobilisation as pain allows once serious causes are excluded.
Step 9 · review & safety-net
Step 9 · Review & safety-netRe-examine; don't miss the emergencies
Same-day / emergency if fever develops, the child won't weight-bear, or pain worsens (septic arthritis — Kocher criteria, urgent aspiration). Review transient synovitis in 24–48h and again if not resolving in a week (reconsider Perthes, JIA, malignancy). Never miss SUFE in an adolescent with hip or knee pain (non-weight-bear + urgent ortho), or NAI — escalate safeguarding for an inconsistent history.
⚠️ A febrile child who will not weight-bear has septic arthritis until proven otherwise — and never miss SUFE in an adolescent (hip or referred knee pain) or non-accidental injury.
🔴 Newborn / infant refuses to move limb
Pseudo-paralysis, crying on nappy change, fever or no fever → Same-day A&E Septic arthritis / osteomyelitis (fever may be absent in neonates)
🔴 Weight loss / pallor / fatigue
Constitutional symptoms with bony pain, lymphadenopathy → 2WW Leukaemia / lymphoma (most common childhood malignancy to present with limp)
🔴 Acute trauma with deformity
Mechanism of injury, deformity, inability to weight-bear, crepitus → Same-day A&E Fracture — including toddler's fracture (subtle spiral)
Septic arthritis is a surgical emergency — cartilage destruction begins within 8 hours of bacterial inoculation due to proteolytic enzymes and pressure necrosis. Hip septic arthritis in children carries a high risk of avascular necrosis of the femoral head if drainage is delayed beyond 24–48 hours. The Kocher criteria (fever, non-weight-bearing, raised ESR >40, raised WBC >12) predict septic arthritis with 99% probability when all 4 present — send to A&E immediately.
Malignancy: Acute lymphoblastic leukaemia classically presents in 2–5 year olds with bone pain and limp — often before blast cells appear on blood film. Night pain and constitutional symptoms are the alarm features. NICE NG12 mandates 2WW referral.
NAI: 10–25% of physical abuse involves fractures. A limp with no clear explanation, bruising in pre-mobile infants, or delayed presentation should prompt immediate safeguarding referral. Document carefully; do not confront carers alone.
2
Diagnose
Apply age-based differential — the single most powerful diagnostic filter
Age narrows the differential dramatically. Ask the age first, then build your differential.
0–2 years
Developmental dysplasia of hip (DDH), toddler's fracture (subtle spiral tibia), septic arthritis, osteomyelitis, NAI — always consider abuse in non-walking children
2–5 years
Transient synovitis (most common overall), septic arthritis, toddler's fracture, leukaemia, Perthes disease (onset peaks 4–8 yr), developmental dysplasia (late presentation)
Age-related prevalence determines pre-test probability before any examination or investigation. Transient synovitis is the most common cause of acute hip pain in children aged 2–10 years, but it is a diagnosis of exclusion — septic arthritis must be excluded first (Kocher criteria). SUFE is the most common hip disorder in adolescents and presents with knee or groin pain — beware the referred pain pattern; the knee is examined but the hip is the problem. Delay in diagnosing SUFE leads to avascular necrosis. Perthes disease runs a 2–4 year course and 60% of cases resolve without surgery if caught early — early MRI referral preserves outcome.
Systematic history directs the differential — never skip preceding illness or trauma history.
Onset & mechanism
Sudden (trauma/fracture) vs gradual (Perthes/JIA) vs insidious (malignancy). Ask: "Did anything happen, even a small bump?" — toddler fractures often have trivial mechanisms
Fever history
Temperature at home, timing, associated rigors → High fever + joint pain = septic arthritis until proven otherwise. Low-grade fever may accompany transient synovitis (25%) or JIA
Night pain waking from sleep = 2WW malignancy. Activity-related = mechanical. Morning stiffness >30 min = JIA / inflammatory. Pain at rest = infection/malignancy
Pain location
Hip → knee referred pain common in SUFE and Perthes — always examine the hip if knee pain. Groin pain = hip pathology until proven otherwise. Heel = Sever's disease
JIA (family history), sickle cell disease, haemophilia, psoriasis (psoriatic arthritis), IBD-related arthritis. Ask about prior episodes (Perthes is recurrent in 10%)
Social / safeguarding
Who was with the child? Does history match the injury? Delayed presentation? Previous attendances? Inconsistent accounts? → Activate safeguarding pathway
Referred pain is the most dangerous diagnostic pitfall: up to 15% of SUFE cases present with isolated knee pain and a normal knee examination — clinicians who only examine the knee miss the diagnosis. Always examine the hip when a child complains of thigh or knee pain.
Morning stiffness >30 minutes is a JIA hallmark — children are often described as "warming up" over the morning. JIA requires 6 weeks of symptoms before formal diagnosis; early referral to paediatric rheumatology avoids joint damage.
Safeguarding: The limp consultation is a key opportunity — 10% of physically abused children present with limb symptoms. The RCGP safeguarding competency requires GPs to consider abuse when injury doesn't fit the story.
Antalgic (short stance phase on painful side) = pain. Trendelenburg (pelvis drops on swing side) = hip abductor weakness (DDH, Perthes). Stiff-knee = quad weakness / knee pain
Hip examination
Log-roll test: pain or reduced internal rotation in early SUFE/Perthes. FABER test (hip flexion-abduction-external rotation). Measure true & apparent leg length. Any restriction of internal rotation = X-ray hip same day
Knee examination
Effusion (patellar tap, bulge sign), tenderness at tibial tuberosity (Osgood-Schlatter), patellar grind, MCL/LCL laxity. Remember: knee pain may be referred from hip
Spine
Lumbar range of movement, Schober's test, sciatic stretch tests. Scoliosis (may cause limp). Tenderness over vertebral bodies (disc/infection)
Lower leg & foot
Sever's disease: squeeze calcaneum → pain. Köhler's: midfoot tenderness over navicular. Plantar fascia tenderness. Toddler's fracture: spiral tibia tenderness on compression
Power, tone, reflexes, sensation in both legs. Bilateral findings or upper motor neurone signs → urgent neurological referral
Log-roll test: The hip is the single most important examination in a limping child. Loss of internal rotation is the earliest sign of Perthes disease and SUFE — often before the child is in severe pain. Any restriction of hip internal rotation warrants same-day plain X-ray (AP and lateral hip).
Trendelenburg gait in a young child suggests hip dysplasia (DDH) or early Perthes — both require urgent paediatric orthopaedic referral.
Fever >38.5°C + restricted hip movement + refusal to weight-bear: Even if CRP is modestly raised, treat as septic arthritis until joint aspiration confirms otherwise. Do not be reassured by a normal inflammatory marker — early septic arthritis can have normal bloods.
5
Diagnose
Investigations — bloods, X-ray, ultrasound, MRI (stratified by urgency)
Investigations are guided by the clinical picture. Do not withhold investigations if septic arthritis is possible — normal bloods do NOT exclude it.
Same-day (if any red flag or diagnostic uncertainty)
FBC + differential
Bloods WBC >12 raises Kocher probability. Blast cells may be absent in early leukaemia — repeat if clinical suspicion. Thrombocytopenia + anaemia → haematology referral
CRP / ESR
Bloods CRP >20 + fever = treat as septic until proven otherwise. ESR >40 in hip pain = high Kocher score. Normal CRP does NOT exclude septic arthritis
Plain X-ray
Imaging AP pelvis + frog-leg lateral hip: SUFE (posterior slip of femoral head — best seen on lateral), Perthes (sclerosis, fragmentation, flattening), fracture. Normal X-ray does not exclude early Perthes or SUFE
Hip ultrasound
Imaging Detects effusion (present in transient synovitis AND septic arthritis — cannot distinguish). Guides aspiration in septic arthritis. Request same-day if septic arthritis suspected
Urgent within 48 hours
MRI hip/pelvis
Imaging Gold standard for Perthes (early avascular necrosis before X-ray changes), osteomyelitis, soft tissue infection, malignancy. Request via paediatric orthopaedics
Blood cultures
If febrile Before antibiotics if septic arthritis suspected and awaiting transfer. Do not delay transfer to take cultures
Clinical diagnosis — heel pain in 8–12 year active children. No X-ray needed (calcaneal apophysitis is normal growth variant)
Osgood-Schlatter
Clinical diagnosis in active adolescents. X-ray only if atypical features or not settling. MRI not routinely indicated
The Kocher criteria (fever, non-weight-bearing, CRP >20, WBC >12) stratify septic arthritis risk: 0 factors = 0.2%, 1 factor = 3%, 2 factors = 40%, 3 factors = 93%, 4 factors = 99%. Children with ≥2 factors should be transferred to A&E for same-day ultrasound and orthopaedic assessment.
X-ray limitations: Early Perthes and SUFE may have normal plain films. A normal X-ray in a child with restricted hip movements and pain requires MRI. SUFE can only be confidently excluded on the frog-leg lateral view — an AP alone misses 15% of cases.
Avoiding unnecessary radiation: Children are more radiation-sensitive than adults. Ultrasound is preferred for effusion detection; MRI for soft tissue and bony detail. Don't X-ray a toddler's "limp" if clinical features clearly point to Sever's or Osgood-Schlatter.
6
Refer
Referral pathway — match urgency to clinical picture
Most limping children with red flags need same-day A&E. Don't manage septic arthritis or SUFE in primary care.
999
Toxic / septic appearance. Fever + hot joint + refuses weight-bearing. Suspected spinal cord compression (bilateral leg weakness, urinary symptoms). Neurovascular compromise of limb
Suspected NAI — contact safeguarding lead. Do NOT discharge before consultant review. Document all findings, take photos if appropriate, use body map
2WW bone
Night pain waking child, unexplained constitutional symptoms, pallor, raised LDH/ALP, lymphadenopathy with bone pain (NICE NG12 — children with suspected bone/soft tissue sarcoma or leukaemia)
Urgent paeds ortho (<2 weeks)
Confirmed or suspected Perthes disease (abnormal X-ray + restricted hip rotation). SUFE confirmed on X-ray — do not allow weight-bearing; refer for pinning same admission
Routine paeds ortho
DDH suspected (click/clunk, positive Barlow/Ortolani in infant). Leg length discrepancy >1 cm. Persistent limp >6 weeks without diagnosis
Transient synovitis (well child, afebrile or low-grade fever, Kocher score 0–1, normal bloods). Osgood-Schlatter. Sever's disease. Overuse injury. Hypermobility-related pain
SUFE is a surgical emergency once confirmed: the child must be non-weight-bearing from the moment of diagnosis and admitted for surgical pinning (in-situ fixation) within 24 hours. Any delay risks further slip and avascular necrosis. Do not send home to await an outpatient appointment.
Perthes disease: Outcome correlates strongly with age of onset and degree of femoral head involvement. Children under 6 have better prognosis; those over 8 with >50% head involvement need containment surgery. Early referral preserves function.
Transient synovitis: Can be managed in primary care only if all of the following are met — well child, afebrile or low-grade fever, Kocher score 0–1, normal CRP/WBC, able to weight-bear. Review within 48 hours; if not improving, re-refer to A&E for aspiration.
7
Treat
Primary care management — transient synovitis, mechanical pain, Osgood-Schlatter, Sever's
Only manage in primary care once serious pathology is excluded. Escalate immediately if not improving as expected.
Condition-specific primary care treatment
Transient synovitis (irritable hip)
Analgesia + rest First-line
Ibuprofen 5–10 mg/kg TDS (max 400 mg/dose) with food. Rest from sport for 1–2 weeks. Review in 48 hours. Resolves spontaneously in 95% within 2 weeks. Recurs in 15% — each recurrence needs re-assessment
Osgood-Schlatter disease
Load management + physio First-line
Reduce high-impact activity (not complete rest). Ibuprofen or paracetamol for pain. Ice 15 min post-activity. Quadriceps stretching programme. Refer physio if persistent >6 weeks. Reassure: resolves at skeletal maturity
Sever's disease (calcaneal apophysitis)
Activity modification + heel raise First-line
Heel wedge insole (5–10 mm). Reduce running/jumping temporarily. Calf stretching exercises. Analgesia: ibuprofen or paracetamol as needed. Resolves with skeletal maturity (usually by 15 years)
Hypermobility-related pain
Physiotherapy First-line
Proprioception and strengthening exercises. Avoid extreme positions. Pacing advice. Consider Beighton score. If recurrent joint dislocations — refer to paeds rheumatology to exclude hEDS
Analgesia ladder for acute limb pain (primary care)
Step 1Paracetamol 15 mg/kg (max 1 g) every 4–6 hours — max 4 doses/24 hr. Safe in all ages, give regularly not PRN for acute pain
Step 2Ibuprofen 5–10 mg/kg (max 400 mg) TDS with food, ≥3 months of age and >5 kg. Avoid in dehydration, renal impairment, active infection (theoretical concern re: NF)
Step 3Alternate paracetamol + ibuprofen every 3–4 hours (staggered). Provides near-continuous analgesia without exceeding doses of either. Suitable for moderate pain
Step 4Refer to A&E — strong opioids require hospital setting in children. Codeine is CONTRAINDICATED in children under 12 and post-tonsillectomy (MHRA 2013)
Hospital-initiated treatments (for context)
Septic arthritis
IV flucloxacillin 25 mg/kg QDS (adjust if MRSA risk / organism). Surgical washout (arthrotomy or arthroscopy). Orthopaedic admission. Duration: typically 2–3 weeks (IV then oral based on response)
Perthes disease
Conservative (activity restriction, physiotherapy) for mild/young cases. Containment surgery (femoral or pelvic osteotomy) for severe/older cases. Managed by paeds orthopaedics
SUFE
In-situ cannulated screw fixation within 24 hours. Contralateral hip pinning may be considered. No weight-bearing until surgery. Long-term avascular necrosis surveillance
JIA
NSAIDs first-line. Intra-articular corticosteroid injections. MTX for oligoarticular/polyarticular. Biologics (anti-TNF) if MTX fails — initiated by paeds rheumatology
Ibuprofen in children: Anti-inflammatory and analgesic — preferred over paracetamol alone for musculoskeletal conditions. Give regularly for the first 48–72 hours (not PRN) to maintain anti-inflammatory levels. The theoretical concern about ibuprofen worsening necrotising fasciitis is based on observational data only — do not withhold if infection has been excluded clinically.
Codeine is banned in children under 12 since the 2013 MHRA restriction following deaths from codeine-morphine ultra-rapid metabolisers. Do not prescribe.
Transient synovitis recurs in 15% and 1–3% ultimately develop Perthes disease — this is why all recurrences need orthopaedic review and MRI consideration. Natural history of TS is benign, but follow-up is mandatory.
Lifestyle is treatment — especially for overuse injuries, hypermobility, and chronic musculoskeletal conditions.
Activity modification (not rest)
For overuse injuries (Sever's, Osgood-Schlatter): reduce load, not eliminate. Swimming and cycling tolerated. Return to sport gradually — "pain is the guide" approach. Complete rest causes deconditioning
Physiotherapy referral
Refer for strengthening, proprioception training, gait re-education. Essential for JIA, hypermobility, post-fracture rehabilitation, DDH. Reduces recurrence of transient synovitis in hypermobile children
Footwear assessment
Cushioned trainers for Sever's. Heel raise insoles (5–10 mm). Avoid flip-flops in children with flat feet or hypermobility. Paediatric orthotics referral if persistent biomechanical issues
Weight management
SUFE risk directly correlates with obesity (BMI >95th centile). Reduce load on developing epiphyses. Refer to dietitian / MEND programme if BMI >91st centile. Supports Perthes outcomes too
School communication
Provide "fit note equivalent" for schools: PE exemption letter, stair access, seating arrangements. Children with JIA or Perthes may need adapted PE plans — coordinate with SENCO. Fatigue management for JIA
Vitamin D supplementation
SACN recommends 400 IU/day for all UK children. Deficiency contributes to bone pain, stress fractures, and periostitis. Check 25-OH vitamin D if unexplained bone pain. Supplement if <50 nmol/L
Calcium-rich diet
3 portions dairy/day (or fortified alternatives) for bone health. Adequate calcium intake critical during rapid growth phases (ages 9–18). Important for children on long-term corticosteroids (JIA)
Mental health & chronic pain
Chronic pain affects school attendance and mental health. Screen for anxiety and depression in children with JIA, hypermobility, or persistent limb pain. Refer to CAMHS / pain psychology if needed. Involve family in pain management approach
Activity modification vs rest: Complete rest worsens outcomes in overuse injuries — bone requires mechanical loading to remodel. The British Journal of Sports Medicine recommends load management (reducing volume by 50%) over complete cessation. Children respond better and faster than adults to structured physiotherapy.
Obesity and SUFE: The incidence of SUFE has risen 3-fold in the UK over the last 30 years, mirroring childhood obesity rates. Obese boys aged 10–14 are the highest-risk group. Weight reduction reduces shear forces on the capital femoral epiphysis and may delay contralateral slip.
Vitamin D: UK children are at high risk of deficiency (high latitude, limited sun exposure, dietary). Vitamin D deficiency causes periosteal reaction mimicking osteomyelitis on X-ray (metaphyseal cupping) and diffuse bone pain. SACN (2016) recommends universal supplementation for all UK children year-round.
9
Safety
Follow-up, safety-netting, and monitoring — never discharge without a safety net
All children managed in primary care for limping must have explicit safety-netting. Document this in the notes.
Transient synovitis: 48 hr
Phone review or same-day review if not improving. If worsening, fever develops, or child now refuses to weight-bear → Same-day A&E. If improving: review at 2 weeks, then discharge if resolved
Transient synovitis: 2 weeks
Should have full resolution. If persistent limp at 2 weeks → plain X-ray hip + urgent paeds orthopaedic referral (exclude early Perthes). Do not discharge a child still limping at 2 weeks
Osgood-Schlatter: 6 weeks
Review response to load management. Refer to physiotherapy if not improving. Re-examine to exclude other pathology. X-ray only if atypical. Reassure: resolves at skeletal maturity (2–3 years)
Sever's disease: 4–6 weeks
Review with insoles in place. Most improve significantly. If bilateral or not resolving: check vitamin D, refer paeds orthopaedics if structural concern
JIA monitoring
Uveitis screening: slit-lamp examination every 3–6 months (ophthalmology) — can be asymptomatic. Joint disease review by rheumatology 3-monthly. Monitor for MTX toxicity (LFTs, FBC). Annual growth monitoring
Post-septic arthritis
Paeds orthopaedic follow-up at 6 weeks, 3 months, 1 year for avascular necrosis surveillance. Parents advised: any return of pain/limp → same-day assessment
Perthes / SUFE
Managed entirely by paeds orthopaedics. GP role: ensure attended follow-up, monitor pain, screen for contralateral SUFE (25% bilateral — refer immediately if new hip/groin pain)
Safety-net instructions (give verbally AND in writing)
999 immediately
Child collapses or loses consciousness. Cannot breathe. Extreme pallor with limb pain. Limb goes cold/white/blue
Same-day A&E
Develops fever >38°C. Refuses to weight-bear (was walking before). Joint becomes hot, red, swollen. Child is vomiting, increasingly unwell. Night pain starts
Return to GP <48 hours
Not improving as expected. New symptoms. Pain spreading. Parent concerned child is "not right". Any doubt — re-examine; a second opinion is appropriate
The 2-week rule for transient synovitis is evidence-based: 98% of true transient synovitis resolves within 2 weeks. Any child still limping at 2 weeks has a diagnosis other than transient synovitis until proven otherwise — Perthes, reactive arthritis, and early JIA are the commonest alternatives. A normal X-ray at 2 weeks does not exclude early Perthes — MRI is needed.
Contralateral SUFE risk: 25–40% of SUFE is bilateral (sequential or synchronous). Children who have had one SUFE fixed must be counselled to return immediately with any new hip, groin, or thigh pain. GP follow-up has a critical role in detecting the contralateral slip early.
JIA uveitis: Oligoarticular JIA carries a 20–30% risk of anterior uveitis — it is painless and can cause blindness if undetected. Children with ANA-positive oligo JIA need 3-monthly slit-lamp screening. GPs must ensure ophthalmology follow-up is active. This is an area where GP-initiated safety-netting prevents preventable visual loss.
Educational use only. Pathway based on: NICE NG12 (Suspected Cancer, 2015, updated 2023) · NICE CKS Limp in Children (2023) · BOAST guidelines for septic arthritis / SUFE · RCPCH JIA guidance (2020) · BSPAR standards for paediatric rheumatology · SACN Vitamin D report (2016) · Kocher MS et al. (JBJS 1999/2004) — Kocher criteria for septic arthritis. Always adapt to individual patient context and local trust guidelines.