Long-term outcome of pigmented villonodular synovitis of the hip after joint preserving therapy.

INTRODUCTION: Pigmented villonodular synovitis (PVNS) is a rare, destructive synovial disease that affects the hip joint the second most common after the knee. However, in contrast, joint preserving surgery in the hip joint is considered to be significantly more difficult or even impossible due to earlier occurrence of osteochondral dissemination and surgical difficulties. Today, earlier diagnosis due to the generous use of MRI and modern surgical strategies raise hope for improved outcomes. METHODS: Since 2005, six patients with PVNS of the hip and a minimal follow-up of 2 years underwent joint preserving surgery in our institution (mean age 20.5 years, range 14-27). After PVNS was suspected in the MRI and confirmed by arthroscopic biopsy (four diffuse, two focal forms), synovectomy was carried out in 5 patients via surgical hip dislocation and in one focal case via arthroscopy. In diffuse forms, adjuvant radiosynoviorthesis (RSO) was conducted 6-8 week postoperatively. MRI and clinical examinations were performed during follow-up. RESULTS: After a mean follow-up of 8 years (range 35-141 months), five of six patients did not show recurrence or secondary osteoarthritis. Clinical outcome evaluation resulted in a mean modified Harris Hip Score of 91 points (range 67-100 points). A 21-year-old patient with a diffuse form and advanced osteochondral involvement at the time of diagnosis was eventually treated by total hip arthroplasty. CONCLUSION: In cases without osteochondral involvement, recurrence-free long-term results without progression of joint degeneration can be achieved by joint preserving therapy.

Arthroscopic Treatment for Primary Septic Arthritis of the Hip in Adults.

Purpose. Primary septic arthritis is a rare differential diagnosis of acute hip pain in adults. Inspired by the success of all-arthroscopic treatment in pediatric patients, we developed a diagnostic and surgical pathway for our adult patients. Methods. Seven patients, average age 44 ± 13.7 years with acute hip pain since 4.4 ± 2.9 days in the average, were included. Septic arthritis was confirmed by joint aspiration and dissemination was excluded by MRI and standard radiographs. Surgical treatment consisted of immediate arthroscopic lavage using 4 portals for debridement, high-volume irrigation, partial synovectomy, and drainage. Results. Patients were treated in hospital for 12.4 ± 3.1 days (range 7-16 days). WBC and CRP returned to physiological levels. During the mean follow-up of 26.4 ± 19.4 months (range 13-66 months) no patient showed recurrence of infection. The 5 patients with an unimpaired hip joint prior to the infection had a mean modified Harris Hip Score of 94 ± 5.6 points (range 91-100) at final follow-up. Conclusions. Arthroscopic therapy using a minimally invasive approach with low perioperative morbidity for the treatment of primary septic arthritis of the adult hip is able to restore normal hip function in acute cases without dissemination of the infection. Level of Evidence. IV.

Arthroscopic treatment of femoroacetabular impingement shows persistent clinical improvement in the mid-term.

INTRODUCTION: The concept of femoroacetabular impingement (FAI) and the indication for surgical intervention have been established in the last decade. Despite promising short-term results and emerging arthroscopic techniques, it remains unclear whether patients benefit from surgical correction in the mid- to long-term and whether progressive joint degeneration can be prevented. MATERIALS AND METHODS: A retrospective study of our first 50 consecutive patients who underwent arthroscopic correction for FAI was conducted. The modified Harris hip score (mHHS) was assessed preoperatively and at final follow-up. In addition, the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) and a subjective hip value (SHV) were added at final follow-up. Degenerative changes according to Kellgren and Lawrence scale and the α angle were analyzed preoperatively and on the most recent radiograph. RESULTS: Of a total of 50 patients, 44 (24 male, 20 female) with a mean age of 34.3 years (17-65) were available with complete follow-up. Of these 44 patients, 39 were treated with correction of the femoral offset for isolated cam deformity, 5 with additional focal pincer correction and partial labral resection. After a mean follow-up of 66.3 ± 14.5 months the mHHS had improved significantly from 67.2 ± 6.4 preoperatively to 86.4 ± 13.5 (p < 0.001). The WOMAC score (converted to 0 = best/100 = worst) resulted in mean indices for the subcategories pain, stiffness and function of 11.8 ± 16.5, 12.2 ± 17.8 and 9.1 ± 16.1. The SHV was reported with a mean of 77.7 ± 21.8 % at final follow-up. The α angle was reduced significantly from 57.2° ± 10.1° to 46.3° ± 7.4° (p < 0.001). The Kellgren and Lawrence score showed a non-significant trend from 2.0 ± 0.8 preoperatively to 2.2 ± 0.9 in the most recent radiograph (p = 0.46). 5 patients had been converted to a total hip arthroplasty a mean of 28 ± 7.1 months postoperatively. These patients were significantly (p < 0.01) older with a mean age of 49.8 ± 7.8 years and showed significantly higher present osteoarthritic changes with an average Kellgren and Lawrence score of 2.6 ± 2.5 before FAI correction (p < 0.01). CONCLUSIONS: Arthroscopic correction of femoroacetabular impingement results in a persistent clinical improvement without significant progression of degenerative changes in the majority of patients. The indication for surgery should be established cautiously when degenerative changes are present. LEVEL OF EVIDENCE: Level IV, Case series with no comparison group.

The Zweymüller threaded cup: a choice in revision? Migration analysis and follow-up after 6 years.

Excellent long-term results are reported for threaded cups with an osteointegrable surface in primary interventions. So far, little data are available on the use of such implants in revision cases. We investigated 30 loosened Aesculap PM threaded cups (Tuttlingen, Germany) with a smooth surface, revised with a conical, corundum-blasted Zweymüller threaded cup (Zweymüller Alloclassic CSF cup, Zimmer, Warsaw, Ind). Aseptic radiological loosening was seen in 8% of cases, and a survival rate of 95% was achieved after 6.1 years. Average migration was 1.4 mm cranially and 0.7 mm medially. The Harris hip score improved from 42 points preoperatively to 75 points at follow-up. Good medium-term results are possible after revision using a threaded cup with an osteointegrable surface, but not if segmental acetabular margin defects are present.