Revision Total Knee Arthroplasty for Instability-Outcome for Different Types of Instability and Implants.

BACKGROUND: Given the mixed outcome after revision total knee arthroplasty (TKA) for instability in the literature and the relative high recurrence of instability, we were interested in the outcome of a cohort of patients operated for various types of clinical instability and with different types of implants. METHODS: A total of 77 patients with unstable TKA were completely revised (19 hinged and 58 condylar implants). We classified the patients in 3 instability groups based on the literature: (1) anterior-posterior flexion instability (N = 29); (2) medial-lateral flexion instability (N = 16); and (3) multiplane instability (N = 32). Patients were evaluated up to 24 months postoperatively, concerning Knee Society clinical rating system, range of motion, visual analog scale (VAS) pain, and VAS satisfaction. RESULTS: For the total group, all outcome scores improved, but substantial residual pain (VAS = 41) was reported. For type of instability, the clinical outcome was similar for all the groups. For type of implant, the hinged group had lower postoperative outcome scores but similar satisfaction scores compared with those in the condylar group. There was a considerable number of insert changes and secondary patellar resurfacing in the condylar group compared with no reoperations in the hinged group. Recurrent instability was not seen in the anterior-posterior flexion instability group and in patients who received a condylar constraint-type implant. CONCLUSIONS: We recommend 3 options in revision TKA for instability: (1) hinged implants in cases with severe ligament instability in multiple planes or bone loss, (2) condylar implants with a posterior-stabilized insert in cases with isolated posterior cruciate ligament insufficiency, and (3) condylar implants with condylar constraints in all other cases.

Surgical technique: Results of stabilization of sternoclavicular joint luxations using a polydioxanone envelope plasty.

BACKGROUND: Surgical treatment options for sternoclavicular joint luxations described in the literature are numerous, although all have limitations. Therefore, there is no favorable surgical treatment for sternoclavicular luxations when nonoperative treatment has failed. DESCRIPTION OF TECHNIQUE: We developed the polydioxanone (PDS) envelope plasty, a modification of the figure-of-eight technique, using a PDS ligament. METHODS: We retrospectively reviewed 39 patients (40 joints), treated with a PDS envelope plasty for invalidating sternoclavicular luxations. The minimum followup was 10 months (average, 52 months; range, 10-171 months). The Simple Shoulder Test (SST), Constant-Murley shoulder score, and subjective categorical results were recorded preoperatively and postoperatively. RESULTS: In most patients, postoperative functional shoulder scores were excellent (mean Constant-Murley score, 90, range, 52-100; mean SST, 10; range, 2-12). Ninety percent of patients had an improvement of shoulder function at followup. Only minor complications occurred. Thirteen percent of patients had spontaneous postoperative subluxations. However, the postoperative shoulder function improved in all these patients. CONCLUSIONS: The PDS envelope plasty is a simple procedure, a modification of the best-reported technique. We have promising results with high shoulder scores. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Acetabular revision with impacted morselized cancellous bone graft and a cemented cup in patients with rheumatoid arthritis. A concise follow-up, at eight to nineteen years, of a previous report.

We previously reported our results at a minimum of three years after thirty-five revisions of total hip arthroplasty acetabular components in twenty-eight patients with rheumatoid arthritis. The revisions were performed with use of impacted morselized bone graft and a cemented cup. This update report presents the results at eight to nineteen years after the surgery, which, to our knowledge, is the longest follow-up available in the literature. No patient was lost to follow-up. Since our previous report, there were two additional cup failures due to aseptic loosening, at ten and sixteen years postoperatively. Kaplan-Meier analysis showed the probability of survival of the acetabular component at twelve years to be 80% (95% confidence interval, 65% to 95%) with removal of the cup for any reason as the end point and 85% (95% confidence interval, 71% to 99%) with aseptic loosening as the end point. Cup revisions performed with cement and use of impaction bone-grafting in patients with rheumatoid arthritis led to acceptable long-term prosthetic survival rates. This technique is attractive from a biological standpoint because of the possibility of maintaining acetabular bone stock.

Bone impaction grafting for corticosteroid-associated osteonecrosis of the knee.

BACKGROUND: Osteonecrosis of the distal portion of the femur produces a segment of dead bone in the weight-bearing portion of the femoral condyle, frequently associated with subchondral fracture and collapse and eventually resulting in secondary osteoarthritis. Treatment of these late stages of osteonecrosis in the knee can be problematic. The purpose of the present study was to evaluate a new surgical technique in which the subchondral osteonecrotic lesion is removed. The bone defect is then reconstructed with impacted bone grafts to prevent collapse and/or to regain distal femoral sphericity. METHODS: In this prospective, one-surgeon study, nine consecutive knees in six patients were studied, all of which had extensive corticosteroid-associated osteonecrotic lesions of the femoral condyles. Six knees had collapsed lesions when they were initially treated. The mean age of the patients was thirty-one years. Both the clinical and radiographic outcomes were assessed at a minimal follow-up time of two years. RESULTS: At a mean follow-up time of fifty-one months, none of the reconstructed knees had been converted to a total knee prosthesis. The objective Knee Society score improved from a mean of 63 to 89 points. The functional Knee Society score improved from a mean of 19 to 81 points. During the follow-up period, there was no progression of collapse observed; however, three knees showed early signs of osteoarthritis. Clinical success was achieved in six of eight knees, and radiographic success was achieved in seven of nine knees. CONCLUSIONS: At the time of writing (at the time of midterm follow-up), this method appears attractive as a joint-preserving procedure. It is a relatively simple procedure that is not likely to interfere with future knee procedures. It appears that this technique can be effective in knees with collapse of the femoral condyle, and it may delay the need for a total knee arthroplasty. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.