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Tumor necrosis factor-alpha antagonists (anti-TNFalpha) have become increasingly more common as a treatment for rheu- matoid arthritis (RA). However, there has been an increased incidence of severe infections in patients taking anti-TNFalpha therapy. We present a case series of RA patients treated with anti-TNFalpha therapy that had previously underwent TJA and subsequently developed periprosthetic infections. All patients had a well-functioning implant for a period of 1 to14 years prior to the development of infection. Each patient underwent two to five different joint replacements, and four patients developed infection in multiple sites. The infections proved difficult to eradicate with four patients requiring multiple procedures, and one patient ultimately requiring a hemipelvectomy. This study suggests that periprosthetic infections acquired by patients on anti-TNFalpha therapy are challenging to eradi- cate and treat; highlighting the need for the establishment of guidelines for perioperative and long-term management of anti-TNFalpha therapy, and infection monitoring in joint replacement patients.

INTRODUCTION: Previous reports in the literature from Europe and Asia cite an increased burden on the local emergency departments and orthopaedic services during the operational period of the ice skating rinks. This retrospective observational study was undertaken in order to report the incidence, characteristic, and severity of injuries during a full season at a large urban ice skating rink, as well as to quantify the added burden the ice skating rink places on the local emergency department and the orthopaedic service. METHODS: All patients seen at our emergency room who sustained an injury at the neighboring "free" ice rink were identified over the 4-month period when it was open. The data collected included type of injury, demographics, and need for surgical treatment. RESULTS: Over this period, 118 patients were seen in our ED (of the 135 referrals from the ice rink logbook); Of these, 43 (38%) required an orthopaedic consult and were evenly divided into upper (22) and lower extremity injuries (21). Sixty-seven percent of the patients were adults, and the most common fractures were ankle and distal radius fractures. There were two open fractures of the distal radius seen in the older patients (both in patients > 50). Overall 32% of patients needed operative treatment. Of the non-orthopaedic injuries, the most common was head injury (25%). CONCLUSIONS: An ice-rink may be "free" but adds sig- nificant burden to the healthcare system, and these costs should be factored in by both the sponsoring body and the healthcare system for treatment of these additional patients.

The geometry of the intercondylar box plays a significant role in the development of patellar clunk syndrome. We reviewed the incidence of patella clunk at mid-to-long-term follow-up of a rotating high-flex versus fixed bearing posterior stabilized TKA design. 188-mobile and 223-fixed bearing TKAs were reviewed for complications, incidence of patellar clunk, treatment, recurrence rates, range of motion, and patient satisfaction. Patellar clunk developed in 22 knees in the mobile (11.7%) and in 4 (1.8%) in the fixed bearing group (P<0.001). 23 out of 26 cases resolved with a single arthroscopic treatment and 2 resolved with a second procedure. The mean postoperative range of motion was 122.4 degrees . All but one patient reported overall satisfaction with the index procedure. In contrast with other recent studies we found a significant incidence of patellar clunk in high-flex mobile bearings. Despite the high rate of patellar clunk syndrome, overall patients did well and were satisfied with their outcomes.

This study investigated the impact of metabolic syndrome (MetS) on perioperative and postoperative complication rates: the results of a cohort of 168 total hip and knee arthroplasties, 63 of normal weight, 105 with obesity without risk factors for metabolic syndrome and 39 with obesity and other factors that classify them with metabolic syndrome. Patients with metabolic syndrome were more likely to have complications than those without metabolic syndrome (P=0.0156). Perioperative and postoperative complication rates for the MetS and control groups were 35.9% and 16.3%, respectively. Elevated BMI was the element of MetS that had the largest impact on post-surgical complication rates, and this was statistically significant (P=0.0028). The presence of MetS in patients undergoing total joint arthroplasty has a significant impact on surgical complication rates. This cannot be attributed to the BMI component alone, and may help guide efforts of patient optimization prior to total joint arthroplasty.

The kinematics of seven knee specimens were measured from 0 to 120 degrees flexion using an up-and-down crouching machine. Motion was characterized by the positions of the centers of the lateral and medial femoral condyles in the anterior-posterior direction relative to a fixed tibia. A modular unicompartmental knee, trochlea flange, and patella resurfacing (multicompartmental knee [MCK] system) were implanted using a surgeon-interactive robot system that provided accurate surface matching. The MCK was tested, followed by standard cruciate retaining (CR) and posterior stabilized (PS) knees. The motion of the MCK was close to anatomic, especially on the medial side, in contrast to the CR and PS knees that showed abnormal motion features. Such a modular knee system, accurately inserted, has the potential for close to normal function in clinical application.

OBJECTIVES: To compare lag-screw sliding characteristics and fixation stability of two cephalomedullary nails (CMN) with different lag-screw designs (solid and telescopic), we conducted a biomechanical study and an analysis of clinical results. METHODS: Six pairs of cadaver femurs with simulated intertrochanteric fractures were randomly assigned to one of two CMN fixations. Femur constructs were statically then cyclically loaded on an MTS machine. Lag-screw sliding and inferior and lateral femoral head displacements were measured, following which failure strength of the construct was determined. Forty-five patients with intertrochanteric fractures treated with these CMN were identified. Medical records and radiographs were reviewed and analyzed using Fisher's exact test and Student's t test to determine lag-screw sliding. RESULTS: No difference was seen with cycling in inferior femoral head displacement between the two screw designs. The solid screw had an average inferior head displacement of 1.75 mm compared with 1.59 mm for the telescoping screw (p = 0.772). The solid lag screws slid an average of 2.79 mm lateral from the nail, whereas the telescoping screws slid an average of 0.27 mm (p = 0.003). In our clinical review, the average lateral sliding of the telescoping screw was 0.5 mm and of the solid screw was 3.7 mm (p < 0.001). Despite differences in lateral sliding, there were no reoperations for prominent or painful hardware in either group. CONCLUSIONS: Both designs are acceptable devices for stabilization of intertrochanteric fractures. Clinical and biomechanical data demonstrate greater lateral sliding in the solid lag-screw group, making for greater potential for lateral-sided hip pain in CMNs with solid lag screws as opposed to telescoping lag screws.

Today, patients with human immunodeficiency virus (HIV) live long enough to develop chronic degenerative and HIV-associated joint disease. There is a growing population of patients infected with HIV who are candidates for total hip arthroplasty (THA). A total of 31 HIV-positive, non-hemophilic patients undergoing 41 THAs at our institution between 2000 and 2012 were identified. In-hospital medical complications were reported in 5 of 41 hips, all of which resolved prior to discharge. Deep infection developed in 1 of 41 hips and revision was required in 3 of 41 hips. These results suggest that low rates of complications and revision can be achieved in the HIV-positive, non-hemophilic population. We believe that with careful patient selection, THA may improve the quality of life in the HIV-positive population.

Our goal was to report a 10-year follow up of linear penetration rates for HCLPE, and to determine whether a difference exists between penetrations measured on pelvis or hip anterior-posterior radiographs. We reviewed 48 total hip arthroplasties where a first-generation HCLPE liner was used. Femoral head penetration was measured on both AP pelvis and hip radiographs. Total wear and wear rate at 10years were 1.26mm and 0.122mm/y, respectively. The rate decreased significantly after the first 2-3years, plateauing at a wear rate of 0.05mm/y for the last 5years. The AP hip total wear and wear rate were 1.38mm and 0.133mm/y respectively, while rates were 1.13mm and 0.109mm/y respectively for the pelvis radiographs (P<.05). We found a significant difference in measurements of linear penetration when comparing AP pelvis vs. hip radiographs with lower rates recorded using an AP pelvis.

The goal of this study was to evaluate the efficacy of arthroscopic lysis of adhesions after total knee arthroplasty (TKA) in improving range of motion (ROM) and providing an improvement in knee function. The authors retrospectively examined 19 patients who underwent arthroscopic lysis of adhesions following TKA due to poor ROM. The criterion for lysis was the inability to flex to 90 degrees at 3 months. All patients were followed for at least 2 years after lysis. Patient demographics, postoperative and follow-up ROM,number of prior surgeries, Knee Society Scores, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) functional scores were collected. Average ROM increased from 75.37 degrees preoperatively to 98.95 degrees postoperatively. The authors found an association between preoperative knee score and change in ROM between pre-arthroscopic lysis and ROM at final follow-up (P=.0188). When the authors examined the relationship between patient body mass index (BMI) and change in ROM,they found that patients with a BMI higher than 30 kg/m2 had a change of 26.44 degrees compared with patients with a BMI lower than 30 kg/m2, who had a change of only 8.75 degrees . A strong association was found between patient height and change in ROM and final ROM achieved (P=.0062 and .0032, respectively). The authors report a successful outcome among study patients. Furthermore, they found an association between patient height, BMI, and preoperative knee score and the improvement achieved after arthroscopic lysis of adhesions following TKA. The current study's results are comparable with those of published results. The authors recommend arthroscopic lysis of adhesions as a treatment option for stiff knees after TKA that fails after at least 3 months of nonoperative treatment.