Perthes Disease

Lower Limb

Overview

Perthes Disease is a childhood hip condition characterized by avascular necrosis of the femoral head epiphysis, typically affecting children aged 4-8 years. The condition results from temporary disruption of blood supply to the femoral head, causing bone necrosis, fragmentation, and potential long-term deformity if inadequately managed. Early diagnosis and appropriate management are crucial to minimize residual disability and prevent premature osteoarthritis.

Pathophysiology

Perthes Disease occurs when the blood supply to the femoral head epiphysis is interrupted, leading to avascular necrosis. The exact etiology remains unclear but involves transient vascular disruption, possibly related to increased intracapsular pressure, inflammation, or thrombosis of the lateral epiphyseal vessels. The disease progresses through four stages: initial (necrosis), fragmentation (revascularization with bone resorption), reossification (new bone formation), and remodeling (reshaping of the femoral head). The extent of femoral head deformity depends on the child's age at onset, the percentage of epiphysis involved, and the quality of containment during the healing phase. Poor outcomes are associated with loss of femoral head sphericity, increased lateral pillar involvement, and inadequate coverage.

Typical Presentation

Site

Anterolateral hip, often unilateral; pain may radiate to medial thigh, knee, or groin

Quality

Dull, aching pain; may be activity-related; sometimes sharp pain with certain movements or muscle spasm

Intensity

Mild to moderate; often intermittent initially, becoming more constant as disease progresses

Aggravating

Weight-bearing activities, running, jumping, prolonged standing, internal rotation and adduction of the hip, fatigue toward end of day

Relieving

Rest, recumbency, heat application, activity modification, anti-inflammatory medication

Associated

Antalgic gait, limping, hip stiffness (especially morning stiffness), limitation of hip abduction and internal rotation, relative leg length discrepancy, Trendelenburg gait, thigh or knee pain (referred), audible clicking or catching, pain with spinal flexion (psoas irritation), muscle wasting of hip flexors and abductors

Orthopaedic Tests

Test descriptions are written with AI assistance from standard clinical texts. Where a test lists Sources, its description has been checked against them; those sources are independent and do not endorse OsteoKit. Accuracy figures and grades (A–D) appear only when checked against the published study; tests without one are marked “No accuracy study”.

Further reading: full test procedures are described in standard clinical examination texts, e.g. Magee & Manske, Orthopedic Physical Assessment (7th ed.), and Cook & Hegedus, Orthopedic Physical Examination Tests: An Evidence-Based Approach (2nd ed.).

No accuracy study

Trendelenburg Test

Procedure

Ask the child to stand on the affected leg for up to 30 seconds while you watch the pelvis from behind.

Positive Finding

The pelvis drops on the opposite side, or the child leans the trunk over the stance leg.

Interpretation

Shows hip abductor weakness or pain inhibition, common in Perthes disease. Any child with a limp needs the hip examined, because hip problems often cause knee pain. A limp with fever or an unwell child is septic arthritis until proven otherwise (same-day referral); an adolescent with hip or knee pain and reduced internal rotation may have a slipped capital femoral epiphysis (urgent X-ray, stop weight-bearing).

Sources

No accuracy study

Thomas Test

Procedure

Child lying on their back. Bring both knees to the chest, then let the affected leg straighten towards the couch while the other knee is held to the chest.

Positive Finding

The affected thigh cannot reach the couch.

Interpretation

Shows a hip flexion contracture, which can develop with pain and stiffness in Perthes disease.

Sources

No accuracy study

Internal Rotation Range of Motion (ROM) Assessment

Procedure

Patient supine with hip flexed to 90 degrees and knee flexed to 90 degrees. Examiner internally rotates the hip and measures the arc of motion using visual estimation or goniometry.

Positive Finding

Loss of internal rotation compared with the contralateral hip, or pain with internal rotation movement

Interpretation

Loss of internal rotation is a characteristic finding in Perthes disease, reflecting femoral head deformity, capsular restriction, or pain inhibition. This restriction contributes to altered gait and may increase risk of secondary osteoarthritis.

Sources

No accuracy study

Abduction ROM Assessment

Procedure

Patient supine or standing; examiner passively or actively abducts the hip and measures the arc of motion. Pain or restriction during movement is noted.

Positive Finding

Reduced hip abduction compared with the contralateral hip, or pain at end-range

Interpretation

Reduced abduction may indicate capsular tightness, femoral head deformity, or pain-guarding. This restriction affects single-leg stance stability and contributes to compensatory gait patterns.

Sources

No accuracy study

Antalgic Gait Observation

Procedure

Watch the child walk and run, from the front, side and behind.

Positive Finding

A limp, shortened stance on the affected side, or a trunk lean over the affected hip.

Interpretation

Perthes disease typically presents in primary-school-aged children with a limp that may be painless or come with knee or thigh pain. A limping child needs referral for hip X-rays (front and frog-leg views). Any child with a limp needs the hip examined, because hip problems often cause knee pain. A limp with fever or an unwell child is septic arthritis until proven otherwise (same-day referral); an adolescent with hip or knee pain and reduced internal rotation may have a slipped capital femoral epiphysis (urgent X-ray, stop weight-bearing).

Sources

No accuracy study

Faber Test (Patrick Test)

Procedure

Child lying on their back. Place the heel of the test leg on the opposite knee and gently lower the knee towards the couch while steadying the pelvis.

Positive Finding

Groin pain or clearly reduced range compared with the other side.

Interpretation

Points to a hip joint problem. In Perthes disease, loss of abduction and internal rotation are the key examination findings.

Sources

⚠ Red Flags

  • •Systemic symptoms: fever, unexplained weight loss, night sweats suggesting infection or malignancy
  • •Acute severe pain with hip effusion on ultrasound raising suspicion of transient synovitis or septic arthritis
  • •Bilateral involvement suggesting metabolic or systemic disorder rather than idiopathic Perthes
  • •Onset before age 4 or after age 8 in typical presentation
  • •Signs of neurological involvement: lower limb weakness, sensory disturbance, or bowel/bladder dysfunction
  • •Acute increase in pain, swelling, or inability to bear weight requiring urgent imaging to rule out acute complications
  • •History of significant trauma preceding symptom onset

⚡ Yellow Flags

  • •Parental anxiety about prognosis and long-term outcome affecting compliance with treatment
  • •Overprotective parenting limiting child's normal activity and social participation
  • •Delayed psychosocial development due to activity restriction and peer comparison concerns
  • •School absences or educational disruption due to frequent medical appointments
  • •Pain catastrophization or excessive focus on symptoms by child or caregiver
  • •Low socioeconomic status affecting access to specialist care or compliance with treatment protocols
  • •Family history of hip dysplasia or connective tissue disorders
  • •Psychological impact of limping or visible gait abnormality on self-esteem

Osteopathic Techniques

Perthes disease heals as the femoral head regains its blood supply; the long-term result depends on how round the head stays. Children under 6 with mild disease usually do well without surgery, and physiotherapy to keep hip abduction and internal rotation is central to non-operative care. A review found no randomised trials and no robust evidence on which non-surgical treatment works best.

Safety: Containment, bracing or casting, and weight-bearing limits are decisions for the orthopaedic team. Work only within their plan.

Region

Hip joint (abduction and internal rotation)

Technique

Articulation, hip
Grade D
Low evidence: expert consensus or could not be verified against literature
No trials of hip mobilisation. Keeping hip abduction and internal rotation is a core aim of non-operative care.

Rationale

Gentle hip mobilisation to keep abduction and internal rotation.

How it's done, cautions & evidence

How it's done

Rhythmic, low-velocity passive movement of the hip joint within its range, with no thrust, usually with the patient supine. In hip osteoarthritis trials it was given as a course of about 9–10 sessions over 5–12 weeks.

Cautions

Side effects are usually mild and short-lived. In one hip osteoarthritis trial, 41% of the active group (manual therapy plus exercise) reported mild side effects, against 14% with sham.

Evidence in Perthes Disease

Searched 26 Oct 2026: no trials of hip mobilisation in Perthes disease. StatPearls makes keeping or restoring hip abduction and internal rotation a core aim of physiotherapy; a 2020 review found no robust evidence on non-surgical treatments.

Region

Hip flexors (psoas, iliacus)

Technique

Muscle energy, psoas
Grade D
Low evidence: expert consensus or could not be verified against literature
No trials of MET. Hip flexor and adductor stretching is part of non-operative care.

Rationale

Muscle energy technique to lengthen the psoas.

How it's done, cautions & evidence

How it's done

The hip is taken into extension to the barrier (prone, or supine with the leg off the table). The patient pulls the hip toward flexion for 3–5 seconds against equal resistance, relaxes, and the hip is taken further into extension. Repeat 3–5 times, then re-check.

Cautions

Do not use with a fracture in the area, an unstable pelvis or hip, recent surgery, or a patient who cannot contract on request or follow directions.

Evidence in Perthes Disease

Searched 26 Oct 2026: no trials of psoas MET in Perthes disease. StatPearls lists stretching of the hip adductors, flexors and internal rotators in non-operative physiotherapy.

Region

Gluteal muscles and deep external rotators

Technique

Soft tissue, lumbar and glutealNo trials found

Rationale

Soft tissue to the gluteal and deep external rotator muscles.

How it's done, cautions & evidence

How it's done

Hands-on soft-tissue work (kneading, stretching and sustained pressure) to the lumbar paraspinals, quadratus lumborum and gluteal muscles, usually prone or side-lying.

Cautions

Only minor side effects have been reported in trials.

Evidence in Perthes Disease

Searched 26 Oct 2026: no trials of gluteal soft tissue technique in Perthes disease.

Sources

Rehabilitation Exercises

Supine Hip Flexion and Extension (Pendulum Movement)

Range of MotionBeginner

Supine Figure-Four Stretch (Hip External Rotator Stretch)

StretchingBeginner

Supine Hip Flexor Stretch (Modified Thomas Stretch Position)

StretchingBeginner

Sidelying Hip Abduction (Clamshell Modification)

StrengtheningBeginner

Sidelying Glute Medius Lift with Hip Flexion

StrengtheningBeginner

Quadruped Hip Extension (Donkey Kick Modified)

StrengtheningIntermediate

Supine Glute Bridge (Bilateral, Progressing to Unilateral)

StrengtheningIntermediate

Standing Hip Abduction with Pelvic Stability (Wall Support)

PosturalIntermediate

Single-Leg Standing with Core Engagement (Supported Progression)

BalanceIntermediate

Aquatic Walking or Swimming (Non-Weight-Bearing)

CardiovascularBeginner

Tandem Standing with Upper Limb Reaching

BalanceAdvanced

Standing Hip Internal and External Rotation (Resistance Band, Progressive Load)

StrengtheningAdvanced

Referral Criteria

  • •Initial diagnosis or confirmation of Perthes Disease: refer to pediatric orthopedic specialist for imaging (X-ray, MRI) and staging
  • •Signs of acute hip pain with effusion: refer to pediatrician or orthopedic surgeon to rule out transient synovitis or septic arthritis
  • •Rapid progression of pain or loss of motion: return to orthopedic specialist for reassessment and consideration of containment therapy (bracing, surgery)
  • •Significant Trendelenburg gait or pelvic instability unresponsive to conservative care: refer to physiotherapy for advanced gait training or consider orthopedic reassessment
  • •Psychological distress or behavioral changes secondary to activity restriction: refer to pediatric psychologist or counselor
  • •Evidence of systemic disease (fever, weight loss, lymphadenopathy): refer to pediatrician for investigation of alternative diagnoses
  • •Bilateral hip involvement: refer to metabolic bone disease specialist or endocrinologist to exclude systemic metabolic disorder
  • •Lack of progress after 3-4 months of appropriate conservative management: refer back to orthopedic specialist for reassessment of containment strategy
  • •Complications such as limb length discrepancy affecting gait: refer to orthopedic surgeon for assessment of need for epiphysiodesis or shoe modification
  • •Age at presentation unusual (before age 4 or after age 8): refer for specialist evaluation to confirm diagnosis and exclude other pathology