The optimal strategy for postoperative deep venous thrombosis (DVT) prophylaxis remains among the most controversial topics in hip and knee arthroplasty. Warfarin, the most commonly used chemical anticoagulant, initially causes transient hypercoagulability; however the optimal timing of treatment with respect to surgery remains unclear. Our purpose was to evaluate the effects of pre- versus postoperative initiation of warfarin therapy with a primary endpoint of perioperative change in hemoglobin (pre- minus post-operative level), with secondary endpoints of postoperative International Normalized Ratio (INR), drain output, and bleeding/thrombotic events. A quasi-experimental study design was employed, under which patients were assigned to begin taking warfarin the night prior to surgery or the night following surgery based on day of the week seen in clinic. An a priori power analysis was conducted in order to ensure appropriate enrollment to detect a 0.5 g/dL difference in perioperative change in hemoglobin between groups, given an alpha level of 0.05 and beta of 0.80. Based on the results, the study included all primary, elective total hip and knee arthroplasties performed by a single surgeon over a 12 month period. Fifteen patients were excluded (7 chronic anticoagulation, 3 hip fractures, 2 medical contraindications, 3 simultaneous procedures), leaving 165 cases (108 hips, 57 knees) available for study. Of these, 73 received warfarin preoperatively (49 hips, 24 knees) and 92 postoperatively (59 hips, 33 knees). Warfarin was dosed according to a standard nomogram in both groups. INR (on postoperative days 1 and 2), perioperative decrease in hemoglobin (difference between level preoperatively and on postoperative days 1 and 2), and drain outputs were compared between groups using a student t test. Adverse events (transfusions, hematomas, epidural complications, and pulmonary embolus) were compared using two-tailed Fischer's exact test.Background
Methods
Modular tapered implants have been suggested as the optimal treatment in patients with severe femoral bone loss undergoing revision total hip arthroplasty (THA). The purpose of this study is to describe minimum 2 year follow up of patients treated with modular tapered prostheses for Paprosky type IIIB and IV femoral bone loss in revision THA. 44 Consecutive patients with Paprosky type IIIB (23) or IV (21) femurs undergoing revision total hip arthroplasty to cementless modular tapered prostheses were studied. Harris Hip Scores were obtained prior to revision on all patients except those presenting with acute implant failure or periprosthetic fracture. 10 Patients were deceased within 2 years of surgery; the remaining 18 were followed for an average of 42 months (range 25-69 months). Clinical outcomes were measured using the Harris Hip Score, and radiographs were assessed for signs of stem loosening or subsidence >4mm.Introduction
Methods
When using press-fit stems in revision total knee arthroplasty (TKA), diaphyseal engagement optimizes stability. Attempts to maximize press fit may lead to periprosthetic fracture; however, the literature offers no guidance regarding the prevalence or management of this complication. The purpose of this study is to report the incidence, risk factors, and outcomes of these fractures. 634 Stemmed implants (307 femoral and 327 tibial) from 413 consecutive revision TKAs were reviewed. Immediate and 6 week post-operative radiographs were examined. Patient age, gender, stem length, diameter, and offset were evaluated as potential risk factors for fracture occurrence using a paired t-test for continuous and a chi-square analysis for categorical variables.Introduction
Methods
Serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and synovial fluid white blood cell (WBC) count and differential are effective in diagnosing periprosthetic joint infection (PPJI); however their utility in patients with inflammatory arthritis is unknown. The purpose of this study is to determine the utility of these tests in patients with inflammatory arthritis. 934 Consecutive revision hip and knee arthroplasties were prospectively evaluated for PPJI. 202 Cases were excluded due to acute post-operative or hematogenous infection. 690 Patients had non-inflammatory and 42 had inflammatory arthritis. Receiver operating characteristic (ROC) curves were used to establish optimal ESR, CRP, WBC, and % neutrophil values for diagnosis of PPJI, and the area under the curve (AUC) was calculated to determine the overall accuracy.Introduction
Methods