Gwo-Chin Lee

Acetabular Revisions Using Trabecular Metal Cups and Augments

The purpose of this study is to evaluate the efficacy of trabecular metal (TM) shells and augments in acetabular revisions with significant pelvic bone loss. We retrospectively reviewed 97 cases of consecutive loose total hip arthroplasty with a minimum of Paprosky grade IIA pelvic bone loss treated with a TM revision acetabular component with or without modular augments. The average Harris hip score improved from 55 preoperatively to 76 postoperatively. At the most recent radiographic evaluation, 88 cups demonstrated no lucent lines, 1 cup had lucent lines but remained well fixed, and 8 cups underwent resection arthroplasty for infection. One cup was revised for chronic instability. There were no aseptic failures in this series. Trabecular metal acetabular cups and shells with or without the use of modular augments can be effectively used to revise failed acetabular components in patients with substantial pelvic bone loss.

Prospective Results of Uncemented Tantalum Monoblock Tibia in Total Knee Arthroplasty Minimum 5-Year Follow-up in Patients Younger Than 55 Years

A significant increase in younger patients undergoing total knee arthroplasty raises the theoretical concern for revision secondary to micromotion and fixation failure with cemented components. We prospectively studied 100 consecutive tantalum monoblock uncemented tibial components and 312 concurrent cemented controls. Patients younger than 55 years with adequate bone stock were enrolled. This cementless patient group was younger and had higher preoperative functional status. Prostheses were posterior-substituting uncemented femoral and tibial components with a cemented patellar button. Knee Society pain and function scores and radiographs were obtained, and a cost analysis was performed. Knee Society scores were excellent and equivalent beyond 6 months. There was no significant difference in perioperative blood loss, complication rates, or cost. There was a significant decrease in operative time in the uncemented group. Radiographs revealed no failures of ingrowth at last follow-up. There were 3 uncemented group failures, but none were due to failure of fixation. The use of a porous tantalum tibia at minimum 5 years has yielded promising clinical and radiographic results in a younger patient population.

Modern Total Hip Arthroplasty in Patients Younger Than 21 Years

Total hip arthroplasty (THA) is not commonly performed in adolescents. However, it may be the only option for pain control with continued mobility for advanced disease. We report our experience with modern alternative-bearing THA in patients younger than 21 years. Twenty-one THAs (18 patients) were followed. Preoperative and postoperative Harris hip scores were recorded, and radiographs were reviewed. Average follow-up was 49 months (range, 25-89). Underlying etiology was chemotherapy-induced osteonecrosis (33%), steroid-induced osteonecrosis (29%), sickle cell disease (24%), and chronic dislocation (14%). Articulation bearings were ceramic/ceramic (67%), metal/highly cross-linked polyethylene (29%), and metal resurfacing (5%). Mean age was 18 years (range, 13-20). Harris hip scores improved from 43.6 to 83.6 (P < .001). At final follow-up, there was no radiographic loosening; 1 THA was revised for a cracked ceramic liner. At intermediate-term follow-up, clinical and radiographic results are favorable after alternative-bearing THA in patients younger than 21 years.

Complications Following Direct Anterior Hip Procedures: Costs to Both Patients and Surgeons.

A systematic review of the literature on clinical outcomes following direct anterior approach (DAA) hip arthroplasty was performed. An aggregated 11,810 hip procedures were analyzed for intraoperative and early postoperative complications. The most common complication following DAA hip arthroplasty was nerve dysfunction (2.8%) followed by intraoperative fractures (2.3%). Postoperative dislocation, wound complications, and revision THA within the first 12 months were reported in 1.2% of cases. Thus, while DAA hip arthroplasty can be successfully performed, it is not without complications. Without definitive evidence of clinical superiority, surgeons considering switching to DAA should benchmark their personal complication rates against published reports.

Should All Patients Be Included in Alternative Payment Models for Primary Total Hip Arthroplasty and Total Knee Arthroplasty

BACKGROUND Alternative payment models in total joint replacement incentivize cost effective health care delivery and reward reductions in length of stay (LOS), complications, and readmissions. If not adjusted for patient comorbidities, they may encourage restrictive access to health care. METHODS We prospectively evaluated 802 consecutive primary total hip arthroplasty and total knee arthroplasty patients evaluating comorbidities associated with increased LOS and readmissions. RESULTS During this 9-month period, 115 patients (14.3%) required hospitalization >3 days and 16 (1.99%) were readmitted within 90 days. Univariate analysis demonstrated that preoperative narcotic use, heart failure, stroke, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), and liver disease were more likely to require hospitalization >3 days. In multivariate analysis, CKD and COPD were independent risk factors for LOS >3 days. A Charlson comorbidity index >5 points was associated with increased LOS and readmissions. CONCLUSION Patients with CKD, COPD, and Charlson comorbidity index >5 points should not be included in alternative payment model for THA and TKA.

Incidence of Modern Alumina Ceramic and Alumina Matrix Composite Femoral Head Failures in Nearly 6 Million Hip Implants

BACKGROUND Because of improvements in ceramic materials and manufacturing, the incidence of ceramic failures has decreased over time. Recent concerns with corrosion have contributed to an increase in ceramic ball head utilization. The purpose of this study is to report the incidence of modern alumina bearing failures from a single major ceramic manufacturer in nearly 6 million hip implants and to identify trends in the modes of failure of these implants. METHODS Beginning in the year 2000, CeramTec AG (Plochingen, Germany) began a comprehensive program for reporting and gathering failure data on its products. From January 1, 2000, to December 31, 2013, over 3.2 million pure alumina (PA) and 2.78 million alumina matrix composite (AMC) ceramic ball heads were implanted worldwide. During this period, there were 672 PA and 28 AMC femoral head fractures. The fractures were analyzed with respect to time to failure, head size, and implant factors. RESULTS The incidence of clinical fractures of modern PA femoral heads and AMC femoral heads was 1 in 5000 (0.0201%) and 1 in 100,000 (0.0010%), respectively (P < .0001). The majority of implant failures (80%) occurred within 48 months following surgery (P < .01). Fractures were usually associated with specific events such as trauma, mismatched components, and dislocations. Large-diameter PA heads were associated with a lower rate of fracture compared to smaller-diameter femoral heads (0.0316% for 28-mm heads vs 0.0080% for heads 32 mm or greater [P < .01]). Similar trends were observed with AMC heads. The neck lengths of the femoral ball heads were also a factor: a short-taper 28-mm ball head was more likely to fracture compared to other neck lengths (P < .01). CONCLUSION Modern PA ceramic heads are reliable with extremely low risk of fracture. The reliability is even better with AMC heads.

Revision THA in Obese Patients Is Associated With High Re-Operation Rates at Short-Term Follow-Up

We performed a retrospective review of 309 consecutive revision THAs from 2005 to 2009. We identified a subgroup of patients with BMI >35 and compared the operative time, rate of complications, ICU admissions, re-admissions, and re-operations to patients with BMI <35 undergoing revision THA. At a mean follow-up of 36.3 months, there was no significant difference in operative time, perioperative complications, or re-admission rate between the two groups. However, a significantly higher rate of re-operation was observed in the obese group (46% vs. 28%, P=0.015). Obese patients were more likely to undergo reoperation for infection (P=0.017). Patients with high BMI contemplating primary THA should be aware of the potential subsequent complications associated with revision surgery should it become necessary.

Management of Periprosthetic Femur Fractures With Severe Bone Loss Using Impaction Bone Grafting Technique

We present a technique of femoral impaction grafting used for the treatment of periprosthetic femur fractures with severe bone loss after total hip arthroplasty. Seven patients with femoral fractures with compromise of the femoral isthmus were treated with femoral component revision using the impaction grafting bone technique. The average age was 64 years (range, 44-72 years), and 2 patients required mesh augmentation at the time of surgery. The average follow-up for this group of patients was 56 months (range, 39-92 months). Radiographic evaluation revealed healed fractures in all patients and no evidence of implant loosening at a mean of 56 months (range, 39-92 months). There were no cases of infections or dislocations in this series. Impaction grafting technique can be useful in the treatment of periprosthetic femur fractures when bone loss and canal geometry preclude the use of fully coated femoral components.

Bipolar Sealing in Revision Total Hip Arthroplasty for Infection Efficacy and Cost Analysis

Saline-coupled bipolar sealing has shown mixed results in primary arthroplasty. However, this technology has not been studied in infected revision total hip arthroplasty (THA), where morbidity is higher and conventional methods of blood management, such as cell salvage, often cannot be used. This case-matched study of 76 consecutive revision THA for infection included an experimental bipolar sealing group and a control group of conventional electrocautery. Groups were matched for gender, body mass index, American Society of Anesthesiologists classification, and surgery type. Total blood loss, intraoperative blood loss, and perioperative hemoglobin drop were significantly less in the experimental group. In addition, operative time was significantly shorter in the experimental group, which translated into gross savings approximately equal to the cost of the device. The decreases in total blood loss and perioperative hemoglobin decline, along with financial savings, may support the use of bipolar sealing in infected revision THA.

Which patients need critical care intervention after total joint arthroplasty? : a prospective study of factors associated with the need for intensive care following surgery.

Older patients with multiple medical co-morbidities are increasingly being offered and undergoing total joint arthroplasty (TJA). These patients are more likely to require intensive care support, following surgery. We prospectively evaluated the need for intensive care admission and intervention in a consecutive series of 738 patients undergoing elective hip and knee arthroplasty procedures. The mean age was 60.6 years (18 to 91; 440 women, 298 men. Risk factors, correlating with the need for critical care intervention, according to published guidelines, were analysed to identify high-risk patients who would benefit from post-operative critical care monitoring. A total of 50 patients (6.7%) in our series required critical care level interventions during their hospital stay. Six independent multivariate clinical predictors were identified (p < 0.001) including a history of congestive heart failure (odds ratio (OR) 24.26, 95% confidence interval (CI) 9.51 to 61.91), estimated blood loss > 1000 mL (OR 17.36, 95% CI 5.36 to 56.19), chronic obstructive pulmonary disease (13.90, 95% CI 4.78 to 40.36), intra-operative use of vasopressors (OR 8.10, 95% CI 3.23 to 20.27), revision hip arthroplasty (OR 2.71, 95% CI 1.04 to 7.04) and body mass index > 35 kg/m(2) (OR 2.70, 95% CI 123 to 5.94). The model was then validated against an independent, previously published data set of 1594 consecutive patients. The use of this risk stratification model can be helpful in predicting which high-risk patients would benefit from a higher level of monitoring and care after elective TJA and aid hospitals in allocating precious critical care resources.