Idiopathic chondrolysis of the hip

1. IDIOPATHIC CHONDROLYSIS OF THE
HIP

2. INTRODUCTION
 Very rare
 Characterized by
 the destruction of articular cartilage due to an unknown
cause, principally affecting women during adolescence
and producing premature degeneration of hip.
 Insidious onset of pain in hip, thigh, knee.
 Radiographic symmetrical joint space narrrowing.
 Most common cause of degenerative arthritis of hip
in women.
 Most commonly affects hip, but also involves knee,
shoulder, annkle.

3. ETIOLOGY
 Single hip more than double.
 Right hip more than left.
 Six times more common in females.
 Onset most commonly around 11-12 years.
 Theories for causation
 Abnormal chondrocytes metabolism triggered by
unknown environmental event
 Abnormal intracapsular pressure
 Mechanical insult to articular cartilage

4. PATHOLOGY
 Microscopically, zone 1 is missing and zone 2 is
superficial layer.
 Collagen fibrils thinner, more uniform in diameter.
 Degenerating chondrocytes and debris of dead
cells found
 But many chondrocytes are still vital, important for
subsequent regeneration of the articular cartilage.
 IgM and C3 deposited in synovium.

5. CLINICAL FEATURES
 Classical case: premenstrual girl of 11-12 years
with insidious onset of pain in affected hip, anterior
thigh or knee
 Stiffness and limp
 No constitutional symptoms
 If late, fixed contractures, LLD, pelvic obliquity,
incresed lumbar lordosis.

6. LAB FINDINGS
 CBC, CRP, Rh Factor, HLA B27 Ag, ANA, MT,
Blood culture all negative.
 ESR +/-
 Important to rule out other infective and
inflammatory causes of hip in volvement.

7. RADIOGRAPHY
 Early stage: normal xcept regional osteoporosis
 Later: concentric narrowing of joint space, small
subchondral erosions.
 A concentric diminution of the articular space of
less than 3mm is considered diagnostic for
idiopathic chondrolysis.
 Premature closure of capital femoral physis
 Lateral overgrowth of femoral head on neck.
 Protrusio acetabuli

8.  Bone scan: marked periarticular uptake and
premature efusion of epiphysis of GT
 MRI: cartilage loss, small synovial effusion, bone
remodelling, regional muscle wasting

9. NATURAL HISTORY
 Very variable
 Severe stiffness with fibrous ankylosis and pain,
poor outcome.
 Gradual improvement in ROM and joint space.

10. TREATMENT
 TOC : NSAIDs, protected weight bearing,
maintenance of ROM
 bed rest and traction during acute period.
 Indications for surgery not defined, includes
subtotal capsulotomy, contracture and tendon
releases.
 Aggressive physiothrapy post-op.

11. CURRENTLY
 Arthrodiastsis by hinged distraction.
 Provide joint separation and ROM, cartilage healing
permitted by decreasing mechanical load and
stimulating chondrocytes nourishment through
motion and even distribution of synovial fluid

12. LASTLY
 Arthroplasty
 Arthrodesis ...