Treatment of Periprosthetic Femoral Fractures after Hip Arthroplasty / 대한정형외과학회잡지

PURPOSE: To determine results of treatment according to the guidelines of the Vancouver classification in periprosthetic femoral fractures after total hip arthroplasty. MATERIALS AND METHODS: Among 44 cases of periproshtetic femoral fractures after hip arthroplasty treated between Aug. 1991 and Feb. 2008, thirty-two cases with minimum follow-up greater than one year were included. Outcomes were evaluated using the Beals and Tower's critieria. RESULTS: Outcomes were excellent in 27 cases, and poor in 5 cases. Four of 5 cases with poor result were due to non-union. Three cases were treated with internal fixation and 1 case was treated with a conservative method. One case with a poor result was due to loosening of the cemented stem of a Vancouver type B1 fracture. Loosening of the stem after mid to long term follow up occurred in an additional 4 cases (3 cases with a cemented stem in a type B1 fracture, 1 case with a cemented stem of a type C fracture). Loosened stems were revised with a long revision stem. CONCLUSION: For type B1 periprosthetic fractures around a cementless stem, and for type B2, type B3 periprosthetic fractures, treatment according to the guidelines of the Vancouver classification showed excellent results. However, type B1 periprosthetic fractures around a cemented stem showed poor results with non-union or stem loosening. Hence, more rigid fixation using a bone graft or revision of the stem is needed. In type C periprosthetic fractures in osteoporotic patients, closer attentions is needed to avoid complications.

The Prevalence of Bacterial Nasal Colonization in Patients Undergoing Primary Total Knee Arthroplasty

PURPOSE: The objective of the current study was to investigate the prevalence of bacterial nasal colonization in patients who are undergoing primary total knee arthroplasty and to determine whether the prevalence affects the incidence of deep surgical site infections. MATERIALS AND METHODS: Of the 488 consecutive patients (784 knees) who had been screened for bacterial nasal colonization using nasal swab cultures before elective total knee arthroplasties, 434 patients (88.9%) were available for review at one year postoperatively. We assessed the overall rate of deep surgical site infections in the patients with nasal carriage of bacteria (group I) and in those patients without any bacterial nasal colonization (group II), respectively. RESULTS: Of the 434 patients, 69 (15.9%) had nasal carriage of bacteria. There was 1 infection (0.9%) among 113 knees of 69 patients in group I and 10 infections (1.7%) among 591 knees of 365 patients in group II. Those differences were not statistically significant. CONCLUSION: The prevalence of bacterial nasal colonization in patients undergoing primary total knee arthroplasty was 15.9% and the preoperative nasal carriage of bacteria did not affect the rate of deep surgical site infections.

Radiologic Evaluation of Change of Ankle Joint after Total Knee Arthroplasty / 대한족부족관절학회지

PURPOSE: To evaluate the incidence and describe radiologic pattern of ankle arthritis following change of mechanical loading axis by total knee arthroplasty. MATERIALS AND METHODS: We reviewed radiographs of 419 cases, 243 patients underwent total knee arthroplasy from January 2002 to October 2006 retrospectively. We described radiologic parameters around the ankle joint and measured the amount of change of knee varus or valgus angle by comparing preoperative and postoperative anteroposterior standing lower extremities AP X-rays. We divided cases into two groups, one with radiologically arthritic change of the ankle joint and the other one without any radiologic change after surgery. We compared two groups in each parameters and analyzed statistically (SPSS v13.0). RESULTS: Three hundred eighty one cases were divided into varus group and 38 cases in valgus group. 125 cases were divided into ankle arthritic change-positive subgroup among the varus group and 251 cases were in negative subgroup. The amount of varus angle correction by total knee arthroplasty showed significant difference between two subgroups. There was no significant difference in each parameters between subgroups within 38 valgus cases. CONCLUSION: Ankle arthritis can be aggravated after total knee arthroplasty because of the change of mechanical loading axis onto the ankle joint. Therefore it may be needed to evaluate symptoms and function of ankle joints before performing total knee arthroplasties especially in patients with huge varus deformities of knee joints.