Supraphysiologic temperature enhances cytotoxic effects of bupivacaine on bovine articular chondrocytes in an in vitro study.

PURPOSE: The purpose of this study was to determine the effects of temperature or 0.25% bupivacaine treatment in combination with supraphysiologic temperatures on chondrocyte viability. METHODS: Bovine articular chondrocytes in suspension culture were treated with phosphate-buffered saline solution at 20°C, 37°C, 40°C, 42°C, 45°C, 47°C, and 50°C for 15, 30, and 60 minutes or with phosphate-buffered saline solution at 37°C, 45°C, and 50°C for 30 and 60 minutes followed by 0.25% bupivacaine at 20°C for 60 minutes. Chondrocyte viability was analyzed by flow cytometry with the LIVE/DEAD Viability/Cytotoxicity Kit (Molecular Probes, Eugene, OR). Annexin V and ethidium double staining determined whether apoptosis or necrosis occurred. RESULTS: Temperatures from 20°C to 42°C did not cause chondrocyte death. Temperatures at or above 45°C caused significant chondrocyte death, particularly at 50°C for 60 minutes, compared with 37°C at 60 minutes (P < .01). When the chondrocytes were incubated at 50°C, subsequent exposure to bupivacaine significantly increased chondrocyte death compared with the saline solution-treated control group (P < .001). There were additive cytotoxic effects when bupivacaine was combined with supraphysiologic temperatures. It was also found that bupivacaine at supraphysiologic temperatures caused necrosis of articular chondrocytes. CONCLUSIONS: Temperatures at or above 45°C caused significant chondrocyte death. Bupivacaine treatment in the presence of 45°C and 50°C temperatures significantly increased necrosis of bovine articular chondrocytes in this in vitro study. CLINICAL RELEVANCE: Immediate intra-articular injection of bupivacaine after heat-generating procedures may cause damage to the cartilage because of the additive cytotoxic effects of bupivacaine and elevated temperature.

Biomechanical Comparison of UCL Repair Using Suspensory Fixation Versus UCL Reconstruction.

BACKGROUND: Medial ulnar collateral ligament (mUCL) repair is growing in popularity as a treatment for younger athletes with mUCL tears. One of the most recent techniques utilizes a collagen-coated suture tape to augment the repair. The most popular repair technique uses a screw for proximal fixation in the humerus. We present an alternative technique that uses suspensory fixation in the proximal humerus. PURPOSE: To biomechanically compare elbow valgus stability and load to failure of a novel alternative repair technique with suspensory fixation to an mUCL reconstruction. STUDY DESIGN: Controlled laboratory study. METHODS: Eighteen fresh-frozen cadaveric elbows were dissected to expose the mUCL. Medial elbow stability was tested with the mUCL in an intact, deficient-either repaired or reconstructed-state. The repair technique used a suspensory fixation with suture augmentation, and the docking technique was used on all reconstructions. A 3-N·m valgus torque was applied to the elbow, and valgus rotation of the ulna was recorded via motion tracking cameras as the elbow was cycled through a full range of motion. After kinematic testing, specimens were loaded to failure at 70° of elbow flexion. RESULTS: Both ulnar collateral ligament reconstruction and repair restored valgus stability to levels that were not statistically different from intact at all angles of flexion. There was no significant difference in the ultimate torque to failure between repaired and reconstructed mUCLs. CONCLUSION: There was no significant difference in the valgus strength between the mUCL repair with suspensory fixation and the mUCL reconstruction. CLINICAL RELEVANCE: Suspensory fixation is an alternative method for proximal fixation in the mUCL without compromising the strength of the construct.

A Technique Utilizing GraftNet to Fill Graft Donor Sites in Bone-Patellar-Bone Anterior Cruciate Ligament Reconstruction.

Anterior knee pain and patella fracture are 2 potential complications of bone-patellar-bone autograft anterior cruciate ligament reconstruction. Techniques have been developed to minimize the risk of these complications, including filling the defects with autologous bone fragments and augmenting with biologic agents. We have developed a technique that uses a graft collection device to collect the autologous bone graft generated during surgery. This graft augments the larger bone graft derived from the bone plugs. This autologous augmentation provides a complete biologic strategy to potentially reduce the risk of anterior knee pain and potential patella fracture.

Epidemiology of Upper Extremity Injuries in NCAA Men's and Women's Ice Hockey.

BACKGROUND: Ice hockey is a physically demanding sport where athletes are susceptible to a variety of injuries. Several studies reported the overall injury rates in ice hockey; however, there is a paucity of information on upper extremity (UE) injuries among collegiate ice hockey players. PURPOSE: To describe the epidemiology of UE injuries among collegiate male and female ice hockey players with NCAA (National Collegiate Athletic Association) injury surveillance data from 2004-2005 to 2013-2014. STUDY DESIGN: Descriptive epidemiology study. METHODS: Data were obtained from the NCAA Injury Surveillance Program for all UE injuries sustained during the academic years 2004-2005 to 2013-2014. Injury rates, rate ratios (RRs), and injury proportion ratios were reported with 95% CIs. RESULTS: During the 10 years studied, the overall rate of UE injuries for men was higher than that for women (236 vs 125 injuries per 100,000 athlete-exposures [AEs]; RR, 1.89; 95% CI, 1.67-2.15). UE injuries sustained during either pre- or postseason were approximately 3 times higher for men than for women (preseason: 149 vs 53 per 100,000 AEs; RR, 2.83; 95% CI, 1.69-4.74; postseason: 143 vs 49 per 100,000 AEs; RR, 2.91; 95% CI, 1.33-6.38). The overall injury rate was highest during the regular season (men: 257 per 100,000 AEs; 95% CI, 242-272; women: 143 per 100,000 AEs; 95% CI, 126-160). Additionally, the injury rate for men and women was higher during competition than practice (men: 733 vs 83 per 100,000 AEs; 95% CI, 687-780 and 75-92; women: 303 vs 64 per 100,000 AEs; 95% CI, 259-348 and 52-76). The most common injury observed was acromioclavicular joint sprain (men, 29.1%; women, 13.8%). For both groups, acromioclavicular joint injuries accounted for most non-time loss, moderate time loss (2-13 days), and severe time loss (≥14 days) injuries. CONCLUSION: Men and women sustained a significant number of UE injuries playing collegiate ice hockey during the period studied, with acromioclavicular joint sprain being the most common UE injury and the one that most frequently led to significant time loss. These data may provide insight for future injury prevention and guide improvements in training.