Cementless total hip arthroplasty in patients with severely dysplastic hips and a previous Schanz osteotomy of the femur: techniques, pitfalls, and long-term outcome.

BACKGROUND AND PURPOSE: Historically, a Schanz osteotomy of the femur has been used to reduce limp in patients with severely dysplastic hips. In such hips, total hip arthroplasty is a technically demanding operation. We report the long-term results of cementless total hip arthroplasty in a group of patients who had all undergone a Schanz osteotomy earlier. PATIENTS AND METHODS: From 1988 through 1995, 68 total hip replacements were performed in 59 consecutive patients previously treated with a Schanz osteotomy. With the cup placed at the level of the true acetabulum, a shortening osteotomy of the proximal part of the femur and distal advancement of the greater trochanter were performed in 56 hips. At a mean of 13 (9-18) years postoperatively, we evaluated these patients clinically and radiographically. RESULTS: The mean Harris hip score had increased from 51 points preoperatively to 93 points. Trendelenburg sign was negative and there was good or slightly reduced abduction strength in 23 of 25 hips that had not been revised. There were 12 perioperative complications. Only 1 cementless press-fit porous-coated cup was revised for aseptic loosening. However, the 12-year survival rate of these cups was only 64%, as 18 cups underwent revision for excessive wear of the polyethylene liner and/or osteolysis. 6 CDH femoral components had to be revised due to technical errors. INTERPRETATION: Our results suggest that cementless total hip arthroplasty combined with a shortening osteotomy of the femur and distal advancement of the greater trochanter can be recommended for most patients with a previous Schanz osteotomy of the femur. Because of the high incidence of liner wear and osteolysis of modular cementless cups in this series, nowadays we use hard-on-hard articulations in these patients.

Late hardware-induced sciatic nerve lesions after acetabular revision.

UNLABELLED: We encountered late hardware-induced sciatic nerve lesions after acetabular revision in six patients. There were five female patients and one male patient. The mean age of the patients at the time of index acetabular revision was 59.3 years (range, 42-76 years). The interval from the index acetabular revision to the onset of sciatic nerve symptoms averaged 9.4 months (range, 4-16 months) and that from the onset of symptoms to nerve release was 11.3 months (range, 8-13 months), except in two patients with intermittent symptoms in which it was 9 and 10.5 years, respectively. Sciatic nerve release was successful in two patients, but in four patients, the nerve had been partly or entirely cut by the metallic hardware resulting in a permanent deficit. The minimum followup was 2 years (mean, 4 years; range, 2-7 years). Mechanical irritation should be suspected in the case of any late sign of peroneal neuropathy after acetabular revision with a macrocup or antiprotrusion device, and plate fixation of the posterior column. We recommend exploration and nerve release before a permanent lesion of the nerve has developed. LEVEL OF EVIDENCE: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Arthrography for the diagnosis of abductor avulsion after total hip arthroplasty: a comparison of arthrographic and surgical findings in 33 patients.

BACKGROUND: Weakness of the abductor muscles--or even their avulsion--is a potential risk when total hip arthroplasty (THA) is performed using the anterolateral approach. Avulsion of the re-attached gluteus medius leads to a limp, but can also provide an open canal for joint fluid to escape to the trochanteric region. Thus, our hypothesis was that arthrography can be used to diagnose such detachment. METHODS: We compared THA arthrographies with peroperative findings retrospectively in 33 patients who had undergone surgical exploration for a muscle reattachment because of a strong suspicion of abductor avulsion at physical examination. RESULTS: After a mean follow-up time of 22 (2-57) months after THA, 14/33 patients had a positive (pathological) arthrogram whereas 19 had a negative (normal) result. All 14 patients with a positive arthrogram were verified to have an avulsion of the abductor muscle at the operation. 10 of the 19 patients with a negative arthrogram had an intact abductor insertion, but 9 had an avulsion. All of these 9 patients with the peroperatively disclosed avulsion had a fibrous capsule, which obstructed the fistula leading from the joint cavity to the trochanteric bursa region. INTERPRETATION: Arthrography is a valuable diagnostic aid in the evaluation of patients with abductor weakness and with Trendelenburg's gait appearing after a THA performed using the anterolateral approach. A positive finding helps in the operative decision making, but a negative arthrogram is not a reliable predictor.

Cementless total hip arthroplasty in patients with high congenital hip dislocation.

BACKGROUND: The optimal surgical treatment for patients with high congenital dislocation of the hip remains controversial. The purpose of our study was to evaluate the mid-term to long-term results of cementless total hip arthroplasty in such patients. METHODS: The study included sixty-eight total hip replacements performed between 1989 and 1994 in fifty-six consecutive patients with high congenital hip dislocation at our hospital. The cup was placed at the level of the true acetabulum, and a shortening osteotomy of the proximal part of the femur and distal advancement of the greater trochanter were performed in 90% of the hips. At the time of final follow-up, at a mean of 12.3 years postoperatively, fifty-two patients (sixty-four hips) were evaluated by us with a physical examination, determination of Harris hip scores, and radiographs. RESULTS: The mean Harris hip score increased from 54 points preoperatively to 84 points at the time of final follow-up (p < 0.001). There was a negative Trendelenburg sign in fifty-nine (92%) of the sixty-four hips. There were thirteen perioperative complications (19%): three peroneal nerve palsies, one femoral nerve palsy, one superior gluteal nerve palsy, four nondisplaced fractures of the proximal part of the femur, one malpositioned stem perforating the posteromedial cortex of the femur, one superficial wound infection, and two early dislocations. With revision because of aseptic loosening as the end point, the ten-year survival rate for press-fit, porous-coated acetabular components was 94.9% (95% confidence interval, 89.3% to 100%). Eight of nine threaded acetabular components were revised, and the ninth was radiographically loose at the time of the last follow-up examination. The rate of survival for the CDH femoral components, with revision because of aseptic loosening as the end point, was 98.4% (95% confidence interval, 96.8% to 100%) at ten years. CONCLUSIONS: Total hip arthroplasty, with placement of the cup at the level of the true acetabulum, distal advancement of the greater trochanter, and femoral shortening osteotomy, can be recommended for patients with high congenital hip dislocation. Complications such as wear, osteolysis, and cup revision were secondary to the suboptimal design of the acetabular components used in this series.

Total knee arthroplasty in patients with diastrophic dysplasia.

BACKGROUND: Diastrophic dysplasia results in severe disproportionate short stature, generalized joint deformities, and early osteoarthritis. The knee joint often has an abnormal valgus position and is unstable, and degeneration of all joint compartments occurs, even during growth. The purpose of our study was to evaluate the clinical and radiographic results of total knee arthroplasty in a series of patients with diastrophic dysplasia. METHODS: Between February 1992 and March 2000, twenty-one primary total knee arthroplasties were performed on fourteen consecutive patients with severe osteoarthritis due to diastrophic dysplasia. The patients were followed prospectively with clinical examinations, determination of the Hungerford knee scores, and radiographs. Preoperatively, ten knees had chronic dislocation of the patella. The mean duration of follow-up was 3.4 years. RESULTS: The mean Hungerford knee pain and total scores improved from 5.8 points and 46 points preoperatively to 50 points and 83 points, respectively, at the final follow-up examination (p < 0.001 for both comparisons). Two knees required a distal femoral corrective osteotomy because of metaphyseal angulation. None of the total knee arthroplasties had to be revised during the follow-up period. Six complications were recorded. CONCLUSIONS: Total knee arthroplasty substantially improved the function of patients with diastrophic dysplasia. Additional peripatellar procedures were commonly needed, and complications were frequent.

Total hip arthroplasty in diastrophic dysplasia.

BACKGROUND: Diastrophic dysplasia results in severe disproportionate growth failure, multiple joint deformities, and early osteoarthritis of the hips. Mortality is increased in early childhood, but thereafter life expectancy is normal. Because of severe flexion deformities, resting pain, and diminished movements of the hip joints, total hip arthroplasty is indicated at an early age. The purpose of our study was to evaluate prospectively the midterm results of total hip arthroplasty in a consecutive series of patients with diastrophic dysplasia. METHODS: Between 1982 and 1996, forty-one total hip replacements were performed in twenty-four consecutive patients with diastrophic dysplasia (mean age, forty-one years) at our hospital. The patients were followed prospectively for a minimum of five years with clinical examination, determination of Harris hip scores, and radiographs. Twenty-two patients (thirty-eight hips) were examined clinically and radiographically at the time of follow-up, and the remaining two patients (three hips) were contacted only by telephone. The mean duration of follow-up was 7.8 years. RESULTS: The mean Harris hip score increased from 44 points (range, 25 to 66 points) before the operation to 70 points (range, 37 to 89 points) at the final follow-up examination (p < 0.001). Ten complications (24%) were recorded. Five (12%) of the forty-one hips required revision because of aseptic loosening of the acetabular component at a mean of 9.4 years after the primary operation. No revisions were due to aseptic failure of the femoral component. CONCLUSIONS: Implant survival was good and the Harris hip scores increased significantly after total hip arthroplasty in patients with diastrophic dysplasia. However, shortening femoral osteotomy and transposition of the greater trochanter, adductor and flexor tenotomies, and modification of the femoral stem were frequently needed. Total hip arthroplasty is recommended for patients with diastrophic dysplasia and severe degeneration of the hip joints, even for those who are relatively young. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.