Hip Arthroplasty Using the Bencox® Hip System: An Evaluation of a Consecutive Series of One Thousand Cases / 대한고관절학회지

PURPOSE: This is a report on the outcomes associated with a consecutive series of 1,000 cementless hip arthroplasties utilizing the Bencox® hip stem–the first Korean-developed hip prosthesis. MATERIALS AND METHODS: A consecutive series of 1,000 hip arthroplasties using the Bencox® hip stem were analyzed, starting from its initial release (September 2006) until June 2014. Patients in this consecutive series underwent surgery for fractures (n=552), arthritis (n=155), avascular necrosis (n=209), and revisions (n=84). Of these 1,000 cases, patients with a minimum follow-up of at least 1 year (n=616) were retrospectively analyzed for radiographic and clinical outcomes (i.e., Harris hip score). The stability of the prosthesis was evaluated by examining subsidence. RESULTS: During the follow-up period (mean follow-up period of 54.8 months), there were 2 cases requiring revision of the femoral stem–both were caused by periprosthetic fractures and neither involved stem loosening. The mean Harris hip score during follow-up was 95.5. Bone ongrowth occurred in 95% of patients; no cases of subsidence or aseptic loosening of the stem were detected, and no cases of postoperative complications such as ceramic breakage were observed. CONCLUSION: Clinical and radiographic evaluations of hip arthroplasty using the Bencox® hip stem revealed excellent outcomes with an average of 54.8 month follow-up in a consecutive series of 1,000 cases.

Outcomes of Surgical Treatment of Periprosthetic Femoral Fractures in Cementless Hip Arthroplasty / 대한고관절학회지

PURPOSE: We aimed to evaluate the results of surgical treatment of periprosthetic femoral fractures in cementless total hip arthroplasty (THA). MATERIALS AND METHODS: From June 2002 to May 2012, 40 patients who could be followed-up for more than 1 year after surgery were enrolled in this study. The mean duration of follow-up was 28.5 months (range, 15-97 months) and the average age at the time of surgery was 71.5 years (range, 38-89 years). The fracture types were determined by using the Vancouver classification. Among intraoperative fractures, there were type A in 3 hips, type B2 in 2 hips and type B3 in one. Among postoperative fractures, type AG was present in 5 hips, type AL in 2 hips, type B1 in 15 hips, type B2 in 6 hips, type B3 in 3 hips, and type C in 3 hips. Evaluation of the results was based on bony union, stability of the prosthesis, postoperative complications, and Harris hip score at the final follow-up. RESULTS: Bony union was achieved in all but one case and the average time for bony union was 21 weeks. The mean Harris hip score was 86 at the final follow-up. Clinical results were above good in 34 of 40 hips (85.0%). Stem loosening occurred in one patient with a type B1 fracture treated with open reduction and plate fixation. Nonunion was observed in 1 patient with an AG type fracture. CONCLUSION: Open reduction and fixation using a plate with a screw and cerclage wiring provided good results for periprosthetic fractures in patients who had a stable femoral stem without bone defects. Revision surgery with a cementless long stem should be considered in patients with an unstable stem or suspected stability in B1 type of THA using a proximal fixation type.

Radiological Analysis of the Tapered Femoral Stem after Cementless Hip Arthroplasty: Minimum 5 years follow-up / 대한정형외과학회잡지

PURPOSE: We reviewed radiological mid-term results of cementless hip replacement using Mallory-Head tapered titanium femoral stem. MATERIALS AND METHODS: Forty six patients, 50 hips were followed for more than 5 years. Mean age was 56 years, and mean follow-up period was 6.8 years. Radiologically changes in alignment, subsidence and wear rate were measured. Radiolucent line, endosteal spot weld and osteolysis were also assessed according to Gruen zones. RESULTS: All stems showed stable fixation, and radiolucent lines were observed in noncoated zones of 13 cases (26%) . Osteolysis was observed around the proximal stem in 16 cases (32%) , but it did not progress distally. CONCLUSION: With minimum follow-up of 5 years, the tapered titanium femoral stem showed good radiological results, however osteolysis needs more long-term follow-up.

Cementless Hip Arthroplasty in Patients with Avascular Necrosis of the Femoral Head: Long term results in AML / 대한정형외과학회잡지

PURPOSE: We reviewed the clinical and radiological outcomes of total hip arthroplasty and bipolar hemiarthroplasty for avascular necrosis of the femoral head. MATERIALS AND METHODS: From January 1986 to December 1989, 24 cases were treated with total hip arthroplasty and 27 cases with bipolar hemiarthroplasty for avascular necrosis of the femoral head. Clinical outcomes were assessed using Harris Hip Score. Serial radiographs of the hip were used to assess stability of the femoral component, change of the acetabular cup angle, osteolysis of acetabulum or femur, wear of polyliner and erosion of the acetabular cartilage. RESULTS: The average Harris Hip Score was 93.1 in bipolar hemiarthroplasty group and 86.8 in total hip arthroplasty group at last follow up. Femoral osteolysis was observed in 17 patients of 24 total hip arthroplasties and in 14 patients of 27 bipolar hemiarthroplasties. Acetabular osteolysis was observed in 8 cases of 24 total hip arthroplasties. Revision was undertaken 8 cases (33.3%) in the total hip arthroplasty group and 6 cases (22.2%) in the bipolar hemiarthroplasty group. The main causes of revision were wear of polyliner and severe osteolysis in the total hip arthroplasty group and erosion of the acetabular cartilage in the bipolar arthroplasty group. CONCLUSION: The main cause of failure after total hip arthroplasty for avascular necrosis of the femoral head was using a 32 mm femoral head and a polyliner less than 8mm thickness.