Orthopedics - Oleksa A.P. 2006

Congenital and Acquired Deformities of the Lower Extremity
Congenital and Acquired Hip Deformities
Chondrolysis of the Hip Joint

Hip chondrolysis was first described by R. Elmslie in 1913 as a complication of adolescent coxa vara, and in 1930 H. Waldenström identified the morphological substrate of this pathological process.

Hip chondrolysis is referred to in the literature under various names: chondrolyse (R.L. Cruess, 1963; Mers Letts, 1997), Waldenström's disease (L.I. Hansson et al., 1982), the osteochondral form of aseptic Necrosis of the femoral HEAD (J. Ariet, P. Ficat, 1964), and spontaneous hip stiffness (G. Imhäuser, 1976). Such a divergence in terminology is due to the ambiguity surrounding The Nature of the pathology resulting from an insufficient number of clinical observations and studies by various authors.

In the vast majority of publications, hip chondrolysis is equated with necrosis of the articular hyaline Cartilage, which fails to fully reflect the complex pathological process occurring in all elements of the hip joint without exception (V.V. Filipchuk, 1998).

Hip chondrolysis is a rather formidable complication of adolescent Slipped capital femoral epiphysis resulting from inadequate Treatment, which leads to progressive degenerative and dystrophic Changes in the joint.

M. Tachdjian proposed a Classification of femoral head chondrolysis based on the form and Developmental Stages of the pathological process.

V.V. Filipchuk (1998) identified two groups of risk factors for the onset of this pathology:

1) factors associated with the clinical course of adolescent slipped capital femoral epiphysis;

2) factors associated with its treatment.

The first group includes chronic and acute-on-chronic slipped capital femoral epiphysis. The second group comprises skeletal traction, plaster immobilization, intra-articular interventions, repositioning using external fixation devices, Schnek's protrusion during epiphysiodesis, and inadequate muscular decompression during extra-articular corrective femoral osteotomies.

The earliest clinical signs of hip chondrolysis as a complication of adolescent slipped capital epiphysis are Muscle spasm and pain, though radiographic evaluation remains central to Diagnosis. The initial radiographic sign of the onset of chondrolysis is juxta-articular Osteoporosis of the bones forming the acetabulum, as well as the epiphysis and metaphysis of the Femur, followed by joint space narrowing.

V.V. Filipchuk notes that in patients treated with skeletal traction using heavy weights, the joint space appears nearly normal for 2 to 3 months following the removal of traction, despite a complete loss of joint mobility.

Hip scanning using ^99mTc, proposed by G. De Rossi et al. (1973) for diagnosing chondrolysis, is highly informative. Given that osteotropic radioactive technetium accumulates in bone, particularly in metabolically active areas, this diagnostic modality for chondrolysis is indispensable. An elevated level of radioactive isotope uptake in chondrolysis indicates involvement not only of the femoral head but also of the acetabular bones.

V.V. Filipchuk believes that articular cartilage destruction in chondrolysis is caused by:

1. Resorption of the articular cartilage by a pannus advancing from the synovial membrane, leading to its partial or full-thickness destruction in specific areas. These areas may subsequently be replaced by fibrous tissue, while the underlying layers beneath the scar of the superficially damaged cartilage undergo pronounced matrix dystrophy.

2. Dystrophy and lysis of the cartilage matrix resulting from impaired cartilage Nutrition caused by pathological alterations in the synovial fluid and the predominance of Catabolism in metabolic processes. This leads to softening of the articular cartilage, fissure formation, and subsequent matrix lysis, manifesting as reduced elasticity and decreased thickness of the articular cartilage.

3. Chondroresorption of the deep layers of articular cartilage and osteoresorption of the subchondral Bone tissue driven by osteoclastic lysis.

The author disputes the inevitability of articular cartilage necrosis in hip chondrolysis and, moreover, rejects equating hip chondrolysis with articular cartilage necrosis.

Upon detecting early signs of chondrolysis, the primary measures involve unloading the affected limb and initiating comprehensive conservative treatment aimed at improving Blood supply and METABOLISM while halting destructive processes. Attempts to select a graft for the subchondral necrosis zone remain questionable. In cases of osteoarthritis, joint arthroplasty or arthrodesis is performed.