Dislocation and instability complicating low friction arthroplasty of the hip joint

Among the complications in a series of 1,400 consecutive Charnley low friction arthroplasty procedures, there were 8 dislocations, and 3 highly unstable hips. Three dislocations followed severe trauma, in 2 of the 3 there was only fibrous union of the greater trochanter. In all but 2 of the hips, more than one previous operation had been performed. More than one technical fault was evident in most dislocations. Six of the 8 dislocations required reoperation. Meticulous attention to the Charnley procedure, including soft tissue elements of the hip joint is necessary to avoid instability and dislocation following total hip arthroplasty.     

Labrum lesions and residual dysplasia of the hip joint. Definition and prospectives

Labral lesions are a sign of biomechanical decompensation of the hip joint and often represent the first clinical symptom of residual hip dysplasia (RHD) in the adult. Provocation tests (impingement, apprehension) are typical but not specific. Labral lesions and concomitant findings (intra- and extraosseous ganglia, stress bone marrow oedema) can be detected by magnetic resonance arthrography (MRA) with an accuracy of 91%. Primary therapeutic goal is the normalization of the underlying pathomorphology and instability by a redirectional acetabular osteotomy. There are several concepts concerning simultaneous arthrotomy at the time of osteotomy: no arthrotomy at all, selective arthrotomy, routine arthrotomy in every case. There are more clinical studies necessary before one of these concepts can be widely accepted and recommended. Based on preliminary results, palliative arthrotomy with partial labral resection but without corrective osteotomy in osteoarthritis secondary to residual hip dysplasia gives poor results; we therefore urgently dissuade from palliative labral surgery via arthrotomy. Whether labral surgery via arthroscopy might be a useful concept in symptomatic residual hip dysplasia, is still an open question. In this review article, the "state of the art" presented at the "Vienna Labral Symposium 1997" is reflected and summarized. At the end of this article, a "common statement" of the experts is published in English and German language.     

Fractures of the pelvis in children

Pelvic bony injuries are uncommon in children except for avulsion fractures. Medical records and radiographs of 54 children, in whom pelvic fractures were diagnosed from 1974 to 1993, were reviewed. Children 16 years of age and younger who were treated as inpatients were included in this study. Thirty-two patients were boys (59.3%) and 22 were girls (40.7%). In 47 (87.0%) patients, trauma was caused by motor vehicle accidents. The fractures were classified according to the Torode and Zieg classification and the Tile AO/Association for the Study of Internal Fixation classification. Forty-seven (87.0%) children had associated pelvic or extrapelvic injuries. The mean Injury Severity Score was 30.5 (range, 4-66). The AO classification correlated well with the severity of the injury. Eight children (14.8%) died. In most (38 patients = 70.4%) patients, the pelvic bony injury was treated by conservative means. External or internal fixation of the fracture was performed in 16 (29.6%) patients. A followup examination was conducted in 35 of 44 survivors (79.5%; 2 other patients died of unknown causes) with a mean followup of 135 months (range, 18-235 months); 1 additional patient was interviewed by telephone. In this series, long term morbidity was rare and was attributed to severe pelvic ring disruptions, acetabular fractures, or concomitant injuries. It is concluded that in unstable pelvic ring disruptions and acetabular fractures, the principles of management in children should not differ greatly from those in adults. Serious associated pelvic or extrapelvic injuries may pose more management problems than does the pelvic fracture.     

The x-ray examination of the hip joint in children (author''s transl)

Three parkinsonian patients who were nonresponders to levodopa treatment did not improve when shifted to levodopa-decarboxylase inhibitor combination but, instead, experienced involuntary movements. Their plasma levodopa and metabolite profiles showed unusually high baseline 3-0-methyldopa concentrations that further increased significantly during the decarboxylase inhibitor regimen. All patients had 3-0-methyldopa to levodopa ratios greater than 1, even two hours after therapy. Patients who are responders to levodopa-decarboxylase inhibitor combination or to levodopa alone had 3-0-methyldopa to levodopa ratios of less than 1. We discuss the role of 3-0-methyldopa as a metabolite and the significance of the 3-0-methyldopa to levodopa ratio as a predictor of patients' response to levodopa.     

Compression plate fixation of subtrochanteric osteotomies in children

Compression plates provide a reliable method for stabilizing subtrochanteric osteotomies (and fractures when indicated) in children. Apart from a standard compression set, no special appliances are required. The hazards and inconveniences of nail plates and external fixation devices are avoided.     

Predictive value of the hip flexion test for fractures of the pelvis

In 39 patients with pelvic injury, four clinical tests were performed during physical examination. Of these four tests, the positive and negative hip flexion test (active flexion of the hip with extension of the knee) had the highest predictive value for the presence (95 per cent) or the absence of pelvic fractures (90 per cent), respectively. The predictive values of the other three tests (downward compression on the pubic bone, compression on the iliac rings, and distraction pressure on the iliac crests) were considerably lower.     

Salvage of total hip instability with a constrained acetabular component

Between April 1988 and February 1993, 101 constraining acetabular components were implanted into 98 patients. One patient was lost to followup at 8 months. Otherwise, all patients were observed until death or for at least 2 years minimum followup. The average clinical followup for the living patients was 61 months (range, 24-97 months). Indications for the use of the constrained acetabular components were recurrent dislocation (an average of six dislocations, range 2-20) in 56 cases, intraoperative instability in 38 cases, and neurologic impairment in seven cases. For the entire group there were four cases of recurrent dislocation or failure of the component (4%). For the cases where this component was used for recurrent dislocation, 96% (54 of 56 cases) had no additional dislocations. Radiographically, at this short term followup, there was no evidence of an increased incidence of femoral or acetabular component loosening. The authors recommend judicious use of this component as a salvage measure for desperate cases of hip instability during or after total hip arthroplasty.     

Tuberculosis of the hip in children

We have reviewed 74 tuberculous hips in 73 children treated from 1950 to 1991. From 1979 to 1991 we treated 28 patients with rifampicin, isoniazid and pyrazinamide given for nine months (series A), using active mobilisation for the more recent cases. Before this, 46 hips had been treated with streptomycin and isoniazid with or without para-aminosalicyclic acid given for a mean of 18 months (series B), and all these patients were immobilised for a mean of 2.2 years. The radiological appearances at presentation as classified by Shanmugasundaram (1983) predicted the outcome. Most hips were of the 'normal' type (50% and 59% of series A and B respectively) followed by the dislocating type (25% and 13%) and the atrophic type (8% and 9%). There were good or excellent results in 93% of the 'normal' type. All the atrophic type had poor results. The dislocating type had a poor result if the joint space was narrow after reduction of the hip. Early mobilisation had no effect on the outcome of the 'normal' type of disease. The newer drug regimens allowed for shorter courses of treatment, but did not necessarily give a better outcome.     

Fractures of the hip in children and adolescents

Long-term results of 52 fractures of the hip in 51 children and adolescents are discussed. A distinction was made between fractures in children (aged 1 to 11 years) and those in adolescents (aged 12 to 18 years). Irrespective of the type of fracture it was found that immediate operative treatment leads to the best results. In children as well as in adolescents the risk of avascular necrosis, premature closure of the epiphysis and non-union is less following immediate operative treatment than following delayed operative treatment or conservative treatment. The prognosis of these fractures depends on the amount of damage to the vascularization. Treatment of children consisted of open reduction and fixation with K-wires followed by postoperative immobilization in a hip-spica for 6 weeks. Adolescents were treated with three-flanged nails usually without postoperative plaster immobilization. In both children and adolescents internal fixation may also be carried out with screws, in which case these must not cross an open epiphyseal plate. In both groups a non-weight-bearing period of 6 to 12 months is advisable. The results in adolescents were definitely poorer than in children. Seemingly completely destroyed hips can reintegrate even to a nearly "restitutio ad integrum" state after a period of years.