Idiopathic Chondrolysis of the Hip: a Case Report and Review of the Literature

Ann Rheum Dis: first published as 10.1136/ard.44.4.268 on 1 April 1985. Downloaded from

Annals of the Rheumatic Diseases, 1985, 44, 268-272

Case report Idiopathic chondrolysis of the hip: a case report and review of the literature

ANGUS W HUGHES From the Royal Orthopaedic Hospital, Birmingham

SUMMARY A case of idiopathic chondrolysis of the hip in an adolescent Indian girl is reported. The association between idiopathic chondrolysis of the hip and primary protrusio acetabuli (Otto's pelvis) is discussed. Key word: protusio acetabuli.

Chondrolysis of the hip associated with s!ped rotation was limited to 300. There was also somecopyright. upper femoral epiphyses is well recognised,' and minor discomfort in the left hip but with no its association with trauma and prolonged immobi- restriction of movement. lisation has been described.4 7 Idiopathic chondroly- Laboratory investigations showed a mild anaemia sis of the hip was described by Jones in 19718 and of an iron deficiency type (haemoglobin 10 g/dl; sporadic reports have since been made.>'3 The serum iron 6 ,umol/l; serum total iron binding factors include age, sex, and capacity (TIBC) 60-8 saturation 9-9% (nor- known aetiological Rmol/I; http://ard.bmj.com/ racial origin of the patients; the impression is that mal value 15)) but there was no leucocytosis and the this is a disease mainly occurring in teenage female leucocyte differential count was normal; serum Negroes. This paper reports only the second case of platelet concentration was normal. There was a idiopathic chondrolysis of the hip occurring in a slightly raised erythrocyte sedimentation rate (ESR) female Indian girl and reviews the cases previously which was reported as 34 mm/lst h. Rheumatoid described in the literature. factor, antistreptolysin 0 (ASO) antibody titres, sickle cell test, and thalassaemia screen were nor- Case report mal. A biochemical screen was normal, apart from on September 27, 2021 by guest. Protected a persistently raised alkaline phosphatase, which was The patient was a 14-year-old Indian girl who was reported as 28, 22, 24, and 20 KA units on four admitted on 11 November 1983. She was a healthy separate tests, with laboratory normal limits of 3-12 girl with no significant previous illnesses and no KA units. Serum calcium levels were normal. A skin history of recent injury. Her presenting symptoms Mantoux test was normal. were pain of insidious onset in the right hip and leg, Pelvic x-rays taken on 6 December 1983 showed a associated with a limp which had been present definite joint space narrowing affecting the right hip approximately three months prior to admission. (Fig. 1) and possibly some slight cortical haziness On examination she appeared well with no fever affecting the right femoral head. There was regional or lymphadenopathy. All movements of the right osteoporosis. Tomographic studies confirmed the hip were restricted and painful. She had a fixed joint space narrowing and there was no definite flexion deformity of 20' but could flex the right hip bone destruction. A technetium bone scan showed to 1000. There was no external rotation, and internal no specific local abnormality in the region of the right hip. Accepted for publication 2 October 1984. Correspondence to Mr A W Hughes, Orthopaedic Senior The young girl was treated initially with bed rest, Registrar, Royal Orthopaedic Hospital, Birmingham. traction, and paracetamol analgesic. However, since 268 Ann Rheum Dis: first published as 10.1136/ard.44.4.268 on 1 April 1985. Downloaded from

Idiopathic chondrolysis of the hip 269

Fig. 1 Anteroposterior ofpelvis at time ofadmission.

her symptoms did not subside and septic arthritis approximately 1 cm in diameter. There was no could not be excluded, the right hip was explored excessive synovial fluid in the joint. Biopsy material and material taken for biopsy on 9 January 1984. was harvested from the femoral neck, the superior and the lip of the acetabulum, and the capsule copyright. ARTHROTOMY FINDINGS synovium. The capsule was not closed but the The right hip was explored by a Smith-Petersen wound was otherwise closed in layers with suction approach. The capsule was found to be grossly drainage. Postoperatively the wound healed well thickened and oedematous. The synovium was and the girl's right leg was nursed on a continuous hypertrophic, reddened, and oedematous, but there passive motion machine. was no pannus. The articular surface appeared to be Microbiology reports on the biopsy material intact, though a curious indentation on the superior showed no growth and delayed cultures gave no lateral aspect of the femoral head, i.e., the weight- mycobacterial growth. Histological investigation of http://ard.bmj.com/ bearing area, was noticed. This depression was the biopsy material of the synovium and capsule on September 27, 2021 by guest. Protected

Fig.2 Anteroposteriorofpelvis showing progression of protrusio acetabuli. Ann Rheum Dis: first published as 10.1136/ard.44.4.268 on 1 April 1985. Downloaded from

270 Hughes showed non-specific mild chronic inflammatory paper and subsequent reports is shown in Table 1. In changes only. There was no evidence of rheumatoid total 33 females (82-5%) and seven males (17-5%) arthritis or tuberculosis. have been studied, i.e., a ratio of females to males of 5:1. The average age at presentation is a little SUBSEQUENT MANAGEMENT lower for females, 12-5 years (range 9-18 years), The iron deficiency was corrected with oral iron than for males, 14-8 years (range 13-20 years). supplements. With the use of a continual passive There is an apparent preponderance of the right hip motion machine her range of movements improved being more commonl affected (60% of cases), with during the subsequent weeks and she was discharged two cases described 3 with bilateral involvement from hospital on 10 February 1984. She limped less (5% of cases). and could walk without pain. However, subsequent The earlier reports suggested that this disease was x-rays taken on 24 January 1984 showed further loss limited to Negro adolescents8 10 until Wenger, of joint space (Fig. 2) and the development of Michelson, and Ponsetill described two white girls protrusio acetabuli. A final review six months after with the same condition. The racial incidence of the the time of presentation showed that she was now reported cases of idiopathic chondrolysis of the hip pain free, but the right hip was ankylosed with 30° is given in Table 2, which shows that half of the cases fixed flexion and 100 internal rotation and adduction are Negroid, and a third Caucasian. deformity. CLINICAL FEATURES Discussion Moule and Goldingl suggested that there could be a delay in diagnosing this condition; in our review of Jones8 reported the first cases of idiopathic chon- the literature we found that 14 of the 40 cases had drolysis of the hip in 1971, and a summary of this the time of presentation and time of diagnosis recorded. The delay in these cases ranged from 1 to Table I Idiopathic chondrolysis of the hip 18 months. The clinical features of all 40 cases werecopyright. similar. All presented with insidious onset of hip, Female Male leg, or knee pain, associated with a limp, and progressive loss of movements of the affected hip. In Numbers 33 (82-5%) 7 (17-5%) all cases there was no history of significant trauma, Sex ratio 5 1 Age range (yr) 9-18 13-20 though Duncan reported that two of his nine cases Average age (yr) 12 5 14-8 had 'minor trauma'.9 All patients had been other-

wise mobile and quite healthy before the onset ofhttp://ard.bmj.com/ Side affected hip symptoms apart from two reported on by Jones,8 Right 24 (60%) Left 14 (35%) who had been previously immobilised because of Right and left 2 (5%) disease in the opposite hip. All the patients had restricted hip movements at presentation, with fixed Delay in diagnosis flexion deformities and fixed abduction or adduction 14/40 cases=1-18 months deformities. White cell counts, blood cultures, and on September 27, 2021 by guest. Protected Table 2 Summary of reports of idiopathic chondrolysis of the hip

Paper Negro White Hispanic Indian Unknown Total Jones (1971)' 7 1 1 9 Moule and Golding 8 1 (1974)'" 9 Sivananthan (1977)12 1 1 Wenger, Michelson. and Ponseti (1975)" 2 2 Duncan et al. (1979)9 3 5 1 9 Bleck (1983)'3 5 1 2 1 9 Hughes (this paper) 1 1 20 14 2 3 1 40 50% 35% 5% 7-5% 2-5% 100% Ann Rheum Dis: first published as 10.1136/ard.44.4.268 on 1 April 1985. Downloaded from

Idiopathic chondrolysis of the hip 271 rheumatoid factors were normal. In only four of the where some avascular necrosis was noted has been 40 cases was the ESR higher than 30 mm/h. Bleck reported. 12 performed HLA-B27 determinations in six of his nine cases and this was negative in all six cases.'3 DIFFERENTIAL DIAGNOSIS Skin tests for fungal infection were all negative, but Monarticular hip arthritis in adolescence presents a four of Jones' nine cases had a positive skin challenge to the diagnostician. Clinical evaluation, tuberculin test. No other cases were reported with radiological appearances and joint tissue biopsy are similar positive skin reactions. the cornerstone of a firm diagnosis. A differential diagnosis includes: (1) trauma RADIOLOGICAL FEATURES (2) slipped upper femoral epiphysis Bleck'3 gave a detailed report on the radiographic (3) septic arthritis changes seen in idiopathic chondrolysis of the hip. (4) tuberculosis The x-ray features of the 40 reported cases are (5) Perthes' disease summarised in Table 3. Early changes include (6) pigmented villonodular synovitis regional osteoporosis and blurring of the subchon- (7) synovioma and other neoplasm dral line, with reduction of the joint space. In none (8) monarticular rheumatoid arthritis. of the 40 cases was there evidence of epiphyseal slip. Late changes include early closure of capital, and Positive features that should aid in the early trochanteric epiphyseal plates; more severe cases diagnosis of idiopathic chondrolysis of the hip are developed fibrous or bony ankylosis. In less severe the age, sex, and race of the patient who will present cases there was a tendency to show the early changes lame with hip pain and with no history of trauma or of osteoarthritis with marginal osteophyte forma- systemic illness. The patient will be apyrexial with a tion, progressive loss of joint space, and lateral stiff, contracted, painful hip joint, and laboratory

buttress sclerosis. There is a tendency to develop data will not suggest any infections or rheumatoid copyright. secondary protrusio acetabuli with a progressive aetiology. The x-rays will show osteoporosis and decrease in the CE angle of Wiberg. early joint space reduction with no effusion. Joint tissue biopsy may not be necessary and may delay any treatment13 but is required if there is still any PATHOLOGICAL FEATURES doubt in the diagnosis. The histology report will be Seventeen of the 40 cases had reported histological non-specific, and cultures will grow no bacterial were features (Table 2). Essentially these thickening isolates. http://ard.bmj.com/ of the capsufe, with oedematous changes in the capsule and synovium. There was usually no pannus TREATMENT AND PROGNOSIS formation. The synovium has been reported, in In nine cases the mode of therapy was not reported. various papers, as non-specific chronic changes, or Ten cases received non-surgical treatment, including infiltration of plasma cells, or lymphocytes. There early traction followed by non-weight-bearing exer- are articular surface changes with fibrillation and cises and anti-inflammatory analgesics; five of these fragmentation and progressive loss of cartilage. cases went on to develop complete loss of movement Some reports suggest degeneration of chondrocyte but were pain free. Twelve cases were treated with a on September 27, 2021 by guest. Protected nuclei and loss of cells in the lacunae. One case hip spica, and eight of these subsequently developed a fusion. There have been three cases treated by soft Table 3 X-ray features of idiopathic chondrolysis of the tissue releases, and each of these later required hip further surgical procedures. Seven cases have received bony operations, including excision arthroplasty, mould arthroplasty. Wagner resurfacing Early No epiphyscal slip arthroplasty, and arthrodesis. Reduction of joint spacc Of the 31 cases where the treatment and progress Subchondral line blurring have been reported 16 eventually lost all hip Protrusio acetabuli (dccrcased Wibcrg centre cdgc (CE) anglc)2" movements. However, these cases were all pain Osteoporosis free. Nevertheless, it is evident that idiopathic Late chondrolysis of the hip is a progressive destructive No cpiphyscal slip disease for which there is no known effective Early epiphyscal closurc therapy and which carries catastrophic end results Marginal osteophytes and latcral buttrcss Loss of joint space. ankylosis, ostcoarthritis for the children who are unfortunate enough to be affected by the disease. Ann Rheum Dis: first published as 10.1136/ard.44.4.268 on 1 April 1985. Downloaded from

272 Hughes

ASSOCIATION WITH PRIMARY PROTRUSIO References ACETABULI (OTTO PELVIS) 1 Waldenstrom J. On necrosis of the joint cartilage by Otto first described protrusio acetabuli in 1824,14 epiphyseolysis capitis femoris. Acta Chir Scand 1930; 67: and since then there have been reports of this 939-46. condition occurring in childhood. The 2 Cruess R L. The pathology of acute necrosis of cartilage in aetiology of slipping of the capital femoral epiphysis. A report of two cases this condition may be genetic,15 16 due to mechani- with pathological sections. J Bone Joint Surg 1963; 45A: cal deformity of a soft acetabular floor,'7 18 or due 1013-24. to early closure of the triradiate cartilage. 1820 3 Hartmann J T, Gates D J. Recovery from cartilage necrosis Idiopathic following slipped capital femoral epiphysis. A seven year study chondrolysis of the hip may lead to the of 166 cases. Orthop Rev 1972; 1: 33-7. development of protrusio acetabuli in childhood. 4 Jacobs B. Chondrolysis after epiphyseolysis. In: Instruction Seven of the nine cases described by Jones8 de- course lectures. St Louis CV Mosby, The American Academy of veloped protrusio acetabuli, as did one case of Orthopaedic Surgeons. 1972; 21: 224-6. Wenger," Moule and 5 Lowe H G. Necrosis after slipped capital femoral epiphysis. A Golding,'( and the case report on sex cases with recovery. J Bone Joint Surg 1970; 52B: reported here. 108-18. There are similarities in the clinical features of 6 Maurer R C, Larsen I J. Acute necrosis of cartilage in slipped both conditions. Friedenberg21 reports 17 cases of capital femoral epiphysis. J Bone Joint Surg 1970; 52A: 39-50. 7 Heppenstall R B, Marvel J P Jr, Chung S M K, Brighton C T. primary protrusio acetabuli and all were female, and Chondrolysis of the hip. Clin Orthop 1974; 103: 136-42. six were Negro. Crichton and Curlewis22 report 67 8 Jones B S. Adolescent chondrolysis of the hip joint. S Afr MedJ female cases of protrusio acetabuli, and 75% of 1971; 45: 196-202. these cases were Negro, 8-5% white, and 16*5% 9 Duncan J W, Schrantz J L, Nasca R J. The bizarre stiff hip, Indian. In cases of possible idiopathic chondrolysis. JAMA 1979; 231: 382-5. idiopathic chondrolysis of the hip 10 Moule N J, Golding J S S R. Idiopathic chondrolysis of the hip. the probable cause of protrusion is the softening of Clin Radiol 1974; 25: 247-51. the acetabular floor due to the local hyperaemia, 11 Wenger D R, Michelson M R, Ponseti I V. Idiopathic and loss of the normal growth pattern of the chondrolysis of the hip. Report on two cases. J Bone Joint Surg 1975; 57A: 268-71.

triradiate copyright. cartilage. 12 Sivananthan M, Kutty M K. Idiopathic chondrolysis of the hip. The overlap in clinical features of these two Case report with a review of the literature. Aust N Z J Surg diseases suggests that some cases diagnosed as 1977; 47: 229-31. primary protrusio acetabuli may have been cases of 13 Bleck E E. Idiopathic chondrolysis of the hip. J Bone Joint Surg 1983; 65A: 1226-75. idiopathic chondrolysis of the hip and vice versa. 14 Otto A W. Ein becken, mit hagelformg aus gedehnten pfannen. Certainly the case reports of primary protrusio In: Neue seltene beobachtungen zur anatomie, physiologie and acetabuli described by Friedenberg23 (cases 1 and pathologie gehorig. Berlin: A Rucker, 1824; 2: 19. 19.

2), Gilmour20 (cases 1, 2, and 3). Brailsford,19 and http://ard.bmj.com/ 15 Rechtmon A M. Etiology of deep acetabulum and intrapelvic again by Friedenberg2' (cases 1, 2, and 3) could have protrusion. Arch Surg 1936; 33: 122-37. been cases of idiopathic chondrolysis of the hip in 16 Macdonald D. Primary protrusio acetabuli. J Bone Joint Surg adolescent girls. 1971; 53B: 30-6. 17 Hooper J C, Wyn Jones E. Primary protrusio of the acetabulum. J Bone Joint Surg 1965; 53B: 23-9. CONCLUSION 18 Alexander C. The aetiology of primary protrusio acetabuli. BrJ Idiopathic chondrolysis of the hip is a rare clinical Radiol 1965; 38: 567-80. entity where, unfortunately, there is often a delay in 19 Brailsford J F. Bilateral protrusio acetabuli. A progressive diagnosis. There are characteristic clinical and deformity from childhood. J Int Coll Surg 1953; 5: 555-67. on September 27, 2021 by guest. Protected 20 Gilmour J. Adolescent deformities of the acetabulum. An radiological features but no effective therapy to investigation into the nature of protrusio acetabuli. Br J Surg arrest the disease. Non-steroidal anti-inflammatory 1939; 26: 670-99. analgesia has been given, but there have been no 21 Friedenberg Z B. Protrusio acetabuli. Am J Surg 1953; 85: reports on the use of cortisone, which may be more 764-75. 22 Crichton D, Curlewis C. Bilateral protrusio acetabuli (Otto effective if the aetiology is proved to have an pelvis). J Obstet Gynaecol Commonwealth 1962; 69: 47-51. immunological basis. This paper reports the use of 23 Friedenberg Z B. Protrusio acetabuli in childhood. J Bone Joint continuous passive movement in treating idiopathic Surg 1963; 45A: 373-8. chondrolysis of the but we cannot comment 24 Golding J S R. Chondrolysis of the hip. J Bone Joint Surg 1973; hip, on 55B: 214-5. its value. It is suggested that the disease may have 25 Eisenstein A, Rothschild S. Biochemical abnormalities in immunological,24 biochemical,25 or viral origins.'3 patients with slipped upper femoral epiphysis and chondrolysis. Awareness of the existence of this disease will lead J Bone Joint Surg 1976; 58A: 459-67. to earlier diagnosis. Hopefully this in turn will 26 Wiberg G. Studies on diplastic acetabuli and congenital subluxation of the hip joint. With special reference to the remove the speculation on its aetiology and lead to complication of osteoarthritis. Acta Chir Scand [Suppll 1939; effective management. 58: 28-38.