Reliability and validity of the Hartofilakidis classification system of congenital hip disease in adults.

The reliability and validity of the Hartofilakidis et al. classification system in adults with congenital hip disease (CHD) were examined. The radiographs of 102 adult patients (158 hips) with CHD were independently assessed by three senior surgeons. Interobserver variability was assessed by examining the agreement between the three raters while validity of the classification system was assessed by examining the agreement between the assessment by either one of the three raters and the intraoperative finding (reference standard). The interobserver agreement between the three observers was high ranging from 0.720 to 0.854 (substantial to excellent) while the agreement of the preoperative prediction with the intraoperative findings was 87.4% (K = 0.823, excellent agreement). The Hartofilakidis et al. classification system reliably predicts from preoperative pelvis radiographs the bone deficiencies encountered during the operation.

Evaluation of two surgical techniques for acetabular reconstruction in total hip replacement for congenital hip disease: results after a minimum ten-year follow-up.

We have evaluated the results of total hip replacement in patients with congenital hip disease using 46 cemented all-polyethylene Charnley acetabular components implanted with the cotyloplasty technique in 34 patients (group A), and compared them with 47 metal-backed cementless acetabular components implanted without bone grafting in 33 patients (group B). Patients in group A were treated between 1988 and 1993 and those in group B between 1990 and 1995. The mean follow-up for group A was 16.6 years (12 to 18) and the mean follow-up for group B was 13.4 years (10 to 16). Revision for aseptic loosening was undertaken in 15 hips (32.6%) in group A and in four hips (8.5%) in group B. When liner exchange was included, a total of 13 hips were revised in group B (27.7%). The mean polyethylene wear was 0.11 mm/yr (0.002 to 0.43) and 0.107 mm/yr (0 to 0.62) for groups A and B, respectively. Polyethylene wear in group A was associated with linear osteolysis, and in group B with expansile osteolysis. In patients with congenital hip disease, when 80% cover of the implant can be obtained, a cementless acetabular component appears to be acceptable and provides durable fixation. However, because of the type of osteolysis arising with these devices, early exchange of a worn liner is recommended before extensive bone loss makes revision surgery more complicated.

Treatment of high dislocation of the hip in adults with total hip arthroplasty. Operative technique and long-term clinical results.

The clinical results of eighty-four total hip arthroplasties performed through a transtrochanteric approach in sixty-seven patients who had a high dislocation of the hip (the femoral head completely out of the acetabulum), from 1976 to 1994, were reviewed. The acetabular component was placed in the true acetabulum and the femur was shortened at the level of the femoral neck, along with release of the psoas tendon and the small external rotators, in order to facilitate reduction of the components and to avoid neurovascular complications. Eleven hip prostheses (13 per cent) failed at a mean of 6.4 years (range, two months to sixteen years) postoperatively; the failure was due to aseptic loosening of both components in four hips, aseptic loosening of the stem only in three, late infection in three, and malpositioning of the acetabular component that caused recurrent dislocations in one. The other seventy-three hips were functioning well at the latest follow-up examination, two to twenty years (mean, 7.1 years) postoperatively. The overall cumulative rate of success was 92.4 per cent (95 per cent confidence interval, 89.5 to 95.3 per cent) at five years and 88.0 per cent (95 per cent confidence interval, 82.2 to 93.8 per cent) at ten years. We believe that this operative technique of total hip arthroplasty is effective for the treatment of the difficult condition of high dislocation of the hip.

Congenital hip disease in adults. Classification of acetabular deficiencies and operative treatment with acetabuloplasty combined with total hip arthroplasty.

We describe three distinct types of congenital hip disease in adults. The first type is dysplasia, in which the femoral head is contained within the original true acetabulum. The second type is low dislocation, in which the femoral head articulates with a false acetabulum, the inferior lip of which contacts or overlaps the superior lip of the true acetabulum, giving the appearance of two overlapping acetabula. The third type is high dislocation, in which the femoral head has migrated superoposteriorly and there is no contact between the true and the false acetabulum. We describe and classify the acetabular abnormalities and deficiencies found with these three types. If the anterior, posterior, and superior aspects of the acetabular component cannot be covered during a total hip arthroplasty because of a deficient acetabulum in an adult who has congenital hip disease, we advocate and acetabuloplasty technique (which we have named a cotyloplasty) that involves medial advancement of the acetabular floor by the creation of a controlled comminuted fracture of its medial wall, autogenous bone-grafting, and the implantation of a small acetabular component with cement. This procedure was performed in sixty-six patients (eighty-six hips). Forty-nine of the hips had a high dislocation, thirty-one had a low dislocation, and six were dysplastic. Two to fifteen years (mean, seven years) after the operation, the clinical and radiographic results were satisfactory. Only two acetabular components needed to be revised for aseptic loosening, at 5.3 and 7.5 years postoperatively. Moreover, the cumulative success rate for the acetabular components was 100 percent at five years and 93.2 percent at ten years.

Seven- to 20-year outcome of lumbar discectomy.

STUDY DESIGN: A retrospective, follow-up study. OBJECTIVES: To assess the effects of conventional surgery for lumbar disc herniation over an extended period of time and to examine factors that might correlate with unsatisfactory results. SUMMARY OF BACKGROUND DATA: Although the short-term results of lumbar discectomy are excellent when there is a proper patient selection, the reported success rates in the long-term follow-up studies vary, and few factors have been implicated for an unsatisfactory outcome. METHODS: One hundred-nine patients with surgically documented herniated lumbar disc were analyzed, retrospectively, by an independent observer. Long-term follow-up (mean 12.2 years) was done by a mailed, self-report questionnaire that included items about pain relief in the back and leg, satisfaction with the results, need for analgesics, level of activity, working capacity, and reoperations. Subjective disability was measured by the Oswestry questionnaire. Radiographic review was carried out in 66% of patients. End results were assessed using the modified Stauffer-Coventry's evaluating criteria. Several variables were examined to assess their influence to the outcome. RESULTS: The late results were satisfactory in 64% of patients. The mean Oswestry disability score was 18.9. Of the 101 patients who had primary procedures, 28% still complained of significant back or leg pain. Sixty-five percent of patients were very satisfied with their results, 29% satisfied, and 6% dissatisfied. The reoperation rate was 7.3% (8 patients), about one-third of which was due to recurrent disc herniation. Sociodemographic factors predisposing to unsatisfactory outcome, including female gender, low vocational education, and jobs requiring significant physical strenuousness. Disc space narrowing was common at the level of discectomy, but was without prognostic significance. CONCLUSIONS: The long-term results of standard lumbar discectomy are not very satisfying. More than one-third of the patients had unsatisfactory results and more than one quarter complained of significant residual pain. Heavy manual work, particularly agricultural work, and low educational level were negative predictors of a good outcome. These indicators should be used preoperatively to identify patients who are at high risk for an unfavorable long-term result.

Low friction arthroplasty for old untreated congenital dislocation of the hip.

We report the replacement of 42 hips in 34 adults with untreated congenital dislocation. We used Charnley low friction implants, cementing the cup at the level of the true acetabulum after deepening and enlarging it by our own technique of cotyloplasty. Results were evaluated in 38 hips after a mean of 5.5 years. All the patients showed marked improvement, with no infection and, as yet, no late revision. The technical difficulties of the operation and the complications are discussed.

Long-term behaviour of the Charnley offset-bore acetabular cup.

We report the long-term radiological results of 58 total hip arthroplasties (THA) using the Charnley offset-bore acetabular socket. Wear was measured at four sites and radiolucent lines and possible migration were recorded. Four cups were retrieved at revision and were examined using light microscopy, SEM and X-ray microanalysis. At a mean follow-up of seven years the mean wear in the DeLee and Charnley zone I was 0.4 mm and in zone II 0.26 mm. The wear rate was 0.06 and 0.04 mm/year, respectively. Progression of radiolucent lines was seen in five cases (8.6%). Three sockets (5.2%) were revised because of aseptic migration at a mean follow-up of 9.8 years and one socket for infection at two years. The offset-bore acetabular cup had excellent wear behaviour and a low migration and revision rate. We recommend that it should be considered in THA since the use of small cups is increasing, particularly in revision cases.

Failure analysis of two Ti-alloy total hip arthroplasty femoral stems fractured in vivo.

Failure of total hip arthroplasty femoral stems is a serious clinical complication. Even modern metal alloys and designs sometimes suffer such incidents. The reported study aimed at the investigation of the reasons leading the in vivo fracture of two Ti6Al4V femoral stems. Stems were retrieved during revision surgery approximately 2 years postoperatively. Examination and analysis included XRF spectrometry for identification of chemical composition, macroscopic examination and topographical measurements, SEM study of fracture surfaces, study of alloy microstructure by optical microscopy, and finally measurement of mechanical properties by means of tensile testing conducted on alloy samples machined from the stems themselves. Macroscopic examination and measurements showed close topographical similarity between the two fractures. XRF spectrometry, tensile testing, and microstructure analysis identified the alloy as a typical Ti6Al4V surgical titanium alloy. During SEM analysis the fracture surfaces exhibited characteristic fatigue striations tidally running on the cross sections, which were considered as the weakest ones regarding toward geometry and stress concentration. Fracture in both stems occurred due to fatigue along these cross sections.

Survival of the Charnley low-friction arthroplasty. A 12-24-year follow-up of 276 cases.

The long-term results (12-24 years) of Charnley low-friction arthroplasty performed in 113 hips in 93 patients with a mean age of 45 years, were compared to those achieved in 163 hips in 144 patients with a mean age of 66 years treated with the same procedure. Survivorship analysis showed a 73% prosthesis survival after 17 years in the younger age group and an 86% in the older age group.

Epidemiology, demographics, and natural history of congenital hip disease in adults.

This study examined the epidemiology and demographics of congenital hip disease in 468 (660 hips) patients who were examined between 1970 and 1996. In 356 (54%) hips, the diagnosis was secondary osteoarthritis due to congenital hip disease, and in 272 (41%) hips, the diagnosis was idiopathic osteoarthritis. In the remaining 32 (5%) hips, the diagnosis was uncertain. Of the hips with congenital hip disease, 170 (47.7%) hips were dysplastic, 85 (23.9%) had low dislocation, and 101 (28.4%) high dislocation. The majority of patients with congenital hip disease were women (338 [95%] hips). The natural history of the three types of congenital hip disease was studied in 157 patients (202 hips: 102 dysplastic, 42 low dislocation, and 58 high dislocation) who had received no treatment before the initial examination. Average length of follow-up was 17 years. In dysplastic hips, the disease remained undiagnosed until the onset of symptoms at an average age of 34.5 years. In patients with low dislocation, pain had started at an average of 32.5 years due to progressive degenerative arthritis within the false acetabulum. In patients with high dislocation, in the presence of a false acetabulum, pain started at an average age of 31.2 years, while in its absence, pain started at an average age of 46.4 years due to muscle fatigue. These findings suggest dysplasia, low dislocation, and high dislocation in adults are the results of untreated dysplasia, subluxation, and complete dislocation in infancy, respectively.

Long-term mechanical stability of the impacted morselized graft-cement interface in total joint replacement: an experimental study in dogs.

This experimental study compared the long-term (12 months) mechanical stability of the morselized graft-cement interface with the conventional bone-cement interface in both femoral bones of 10 adult dogs. For mechanical testing, three-point bending and push-out loading tests of composite bone-cement beams were used, while the incorporation of the graft was assessed by serial radiographs. Although the parameters fracture load and interface failure load showed inferior values in the specimens with a morselized graft-cement interface compared to those in specimens with a conventional bone-cement interface, no statistically significant differences were found between groups. Radiographic reconstitution of the lateral femoral cortex was observed in all animals at 3 months while signs of advanced remodeling were apparent at 6 months. These results indicate the long-term mechanical stability of the impacted morselized graft-cement interface is comparable to that of the conventional bone-cement interface created in primary total hip replacements provided the grafted area is protected from early heavy loading.

Acetabular reconstruction in patients with low and high dislocation: 20- to 32-year survival of an impaction grafting technique (named cotyloplasty).

We report the results at a mean of 24.3 years (20 to 32) of 61 previously reported consecutive total hip replacements carried out on 44 patients with severe congenital hip disease, performed with reconstruction of the acetabulum with an impaction grafting technique known as cotyloplasty. The mean age of the patients at operation was 46.7 years (23 to 68) and all were women. The patients were followed post-operatively for a mean of 24.3 years (20 to 32), using the Merle d'Aubigné and Postel scoring system as modified by Charnley, and with serial radiographs. At the time of the latest follow-up, 28 acetabular components had been revised because of aseptic loosening at a mean of 15.9 years (6 to 26), and one at 40 days after surgery because of repeated dislocations. The overall survival rate for aseptic failure of the acetabular component at ten years was 93.1% (95% confidence interval (CI) 86.5 to 96.7) when 53 hips were at risk, and at 23 years was 56.1% (95% CI 49.4 to 62.8), when 22 hips remained at risk. These long-term results are considered satisfactory for the reconstruction of an acetabulum presenting with inadequate bone stock and circumferential segmental defects.

Charnley low-friction arthroplasty in patients 35 years of age or younger. Results at a minimum of 23 years.

We evaluated the outcome of 41 consecutive Charnley low-friction arthroplasties (LFAs) performed by a single surgeon in 28 patients aged ≤ 35 years at operation between 23 and 36 years previously. There were 20 women and eight men with a mean age of 32 years (23 to 35) at surgery. Two patients (three hips) were lost to follow-up at 12 and 17 years post-operatively, respectively, and one patient (one hip) died at 13 years post-operatively. These patients were excluded from the final evaluation. The survival rate of the acetabular components was 92.7% (95% confidence interval (CI) 88.7 to 96.7) at ten years, 67.1% (95% CI 59.75 to 74.45) at 20 years and 53.2% (95% CI 45.3 to 61.1) at 25 years. For the femoral component the survival was 95.1% (95% CI 91.8 to 98.5) at ten years, 77.1% (95% CI 73.9 to 80.3) at 20 years and 68.2% (95% CI 60.7 to 75.8) at 25 years. The results indicate that the Charnley LFA remains a reasonable choice in the treatment of young patients and can serve for comparison with newer techniques and implants.

Trochanteric osteotomy in total hip replacement for congenital hip disease.

We studied the effect of trochanteric osteotomy in 192 total hip replacements in 140 patients with congenital hip disease. There was bony union in 158 hips (82%), fibrous union in 29 (15%) and nonunion in five (3%). The rate of union had a statistically significant relationship with the position of reattachment of the trochanter, which depended greatly on the pre-operative diagnosis. The pre-operative Trendelenburg gait substantially improved in all three disease types (dysplasia, low and high dislocation) and all four categories of reattachment position. A persistent Trendelenburg gait post-operatively was noticed mostly in patients with defective union (fibrous or nonunion). Acetabular and femoral loosening had a statistically significant relationship with defective union and the position of reattachment of the trochanter. These results suggest that the complications of trochanteric osteotomy in total hip replacement for patients with congenital hip disease are less important than the benefits of this surgical approach.

An examination of the association between different morphotypes of femoroacetabular impingement in asymptomatic subjects and the development of osteoarthritis of the hip.

We retrospectively examined the long-term outcome of 96 asymptomatic hips in 96 patients with a mean age of 49.3 years (16 to 65) who had radiological evidence of femoroacetabular impingement. When surveillance commenced there were 17, 34, and 45 hips with cam, pincer, and mixed impingement, respectively. Overall, 79 hips (82.3%) remained free of osteoarthritis for a mean of 18.5 years (10 to 40). In contrast, 17 hips (17.7%) developed osteoarthritis at a mean of 12 years (2 to 28). No statistically significant difference was found in the rates of development of osteoarthritis among the three groups (p = 0.43). Regression analysis showed that only the presence of idiopathic osteoarthritis of the contralateral diseased hip was predictive of development of osteoarthritis on the asymptomatic side (p = 0.039). We conclude that a substantial proportion of hips with femoroacetabular impingement may not develop osteoarthritis in the long-term. Accordingly, in the absence of symptoms, prophylactic surgical treatment is not warranted.

Congenital hip disease in adults: terminology, classification, pre-operative planning and management.

This paper reviews the current knowledge relating to the management of adult patients with congenital hip disease. Orthopaedic surgeons who treat these patients with a total hip replacement should be familiar with the arguments concerning its terminology, be able to recognise the different anatomical abnormalities and to undertake thorough pre-operative planning in order to replace the hip using an appropriate surgical technique and the correct implants and be able to anticipate the clinical outcome and the complications.

Unilateral hip osteoarthritis: can we predict the outcome of the other hip?

OBJECTIVE: The objective of this study was to define, in unilateral hip osteoarthritis (OA), factors predicting the outcome of the other hip. MATERIALS AND METHODS: We examined the anteroposterior radiographs of the pelvis of 95 white patients with unilateral idiopathic (56 patients) or secondary to congenital hip diseases (39 patients) OA. The other hip was free from symptoms (pain or limping) at the initial examination and without radiographic evidence of OA; it was what we call a "normal" hip. Two parameters were evaluated: (1) the type of osteoarthritis of the involved hip and (2) the range of four radiographic indices of the contralateral hip: the sourcil inclination (weight-bearing surface), the acetabular angle, the Wiberg's center-edge angle, and the neck-shaft angle. Follow-up radiographs for the hips that remained OA-free were available for 10 to 35 years and for those that developed OA, at the time of initial symptoms, range 2 to 31 years. RESULTS: Logistic regression analysis showed that the presence of idiopathic OA in one hip had a statistically significant effect on the development of OA on the other hip (p < 0.001). Minor deviations of radiographic indices of the contralateral hip is not a predictive factor for its outcome. When the radiographic indices are examined together with the pathology of the involved hip, only WBS was shown to have a significant effect to the development of OA and its type (p < 0.001). CONCLUSIONS: The following conclusions can be drawn from this study: 1. Patient with idiopathic OA of one hip is at increased risk of developing OA in the other hip. 2. The outcome of the other hip cannot be predicted only on the basis of the evaluation of its radiographic indices. 3. Among the different indices, WBS seems to have a strong influence toward the development of OA.