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Background: The overhead-throwing athlete is a unique patient, requiring an elite, precise functional ability. Superior labral tears are quite common, and the percentage of athletes who return to play after superior labrum anterior-posterior (SLAP) repair has been variable. A tear of the infraspinatus caused by either internal impingement or tension overload may compromise this return., Hypothesis: The rate of return to a level of play similar to or greater than the preinjury level after repair of combined SLAP and infraspinatus injuries will be lower than in previous reports of SLAP repair alone., Study Design: Case series; Level of evidence, 4., Methods: In the current study, we examined a series of overhead-throwing athletes with diagnoses of both a SLAP tear and a significant (>50%) tear of the infraspinatus tendon who underwent surgical repair of both injuries. We identified 17 high-level baseball players younger than 25 years who underwent simultaneous arthroscopic repairs of a SLAP tear with a standard suture anchor technique and of an infraspinatus tear with either a free polydioxanone (PDS) suture or suture anchor between 2005 and 2008. The postoperative records of all patients were reviewed to determine their ability to return to play and their postoperative level of performance. All patients were then contacted to determine their Kerlan-Jobe Orthopaedic Clinic Overhead Athlete Shoulder and Elbow score and their current sport participation level., Results: All 17 patients in the series attempted to return to their prior sport after completion of postoperative rehabilitation. Only 6 patients (35%) were able to return to the same or a superior preinjury level of performance. Five of the remaining 11 patients returned to play at a lower level, either playing the same position or else forced to switch to another position of play because of a decline in throwing velocity. Six patients were unable to return to play. No complications or reoperations occurred in any of the patients following surgery., Conclusion: A significant (>50%) tear of the infraspinatus in combination with glenohumeral internal rotation deficit (GIRD) and SLAP tears in the throwing athlete results in a guarded prognosis in return to play at the same level. While the rates of return to play in overhead-throwing athletes with an isolated SLAP tear have historically been encouraging, the prognosis for an athlete with both a SLAP and infraspinatus tear is more guarded. These patients are not likely to return to their preinjury level of play.

Background: Infections following hip and knee replacements can compromise the function and durability of arthroplasty. When these infections occur during the immediate postoperative period, irrigation and débridement can be attempted to salvage the implant. Prior studies have reported varying results likely due to lack of consistent inclusion criteria, variations in surgical technique, and lack of uniform treatment protocols., Questions/purposes: To supplement this literature we determined the rate at which irrigation and débridement and prosthesis retention would control acute periprosthetic infections., Methods: We retrospectively reviewed the medical records of 18 patients with acute periprosthetic infections occurring within 28 days after 13 THAs and 5 TKAs. The mean time to reoperation was 19 days (range, 6-28 days) after arthroplasty. Superficial débridements were performed in five cases, and a polyethylene or ball head exchange was performed in the remaining 13 cases when fascial defects were encountered at the time of surgery., Results: We salvaged the prosthesis in four of five patients with superficial irrigation and débridement group and eight of 13 with deep infections. Intraoperative cultures were positive in 83% of cases (n = 15). Five patients (one superficial and four deep) eventually underwent resection arthroplasty. Three patients underwent repeat irrigation and débridement, and one of these three ultimately had resection arthroplasty. Polymicrobial infections were detected in four cases, all failures. The average time to resection was 62 days (range, 12-134 days)., Conclusions: Consistent with the literature, success of prosthesis salvage for periprosthetic infections occurring within 28 days after arthroplasty depends on the location, extent, and microbiology of the infection., Level of Evidence: Level IV, case series. See the Guidelines for Authors for a complete description of levels of evidence.

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.

Purpose: Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine shown to inhibit scar formation in fetal wound healing. The role of IL-10 in adult tendon healing and scar formation, however, remains unknown. The objective of this study is to investigate the effect of IL-10 overexpression on the properties of adult healing tendon using a well-established murine model of tendon injury and a lentiviral-mediated method of IL-10 overexpression., Methods: A murine model of patellar tendon injury was used and animals divided into 3 groups. Mice received bilateral patellar tendon injections with a lentiviral vector containing an IL-10 transgene (n = 34) or no transgene (n = 34). Control mice (n = 34) received injections of sterile saline. All animals then were subjected to bilateral, central patellar tendon injuries 2 days after injection and were killed at 5, 10, 21, and 42 days after injury. IL-10 content was analyzed by immunohistochemistry (n = 4/group). Tendon healing was evaluated by histology (n = 4/group) and biomechanical analysis (n = 10/group)., Results: Overexpression of IL-10 in patellar tendon was confirmed after injection of the lentiviral vector. IL-10 immunostaining was increased at day 10 in the IL-10 group relative to that in controls. Histologically, there was no significant difference in angular deviation between groups at day 21, but a trend toward decreased angular deviation in controls relative to that in empty vector group mice was seen at day 42. Biomechanically, the IL-10 group showed significantly increased maximum stress at day 42 relative to that in controls. Percent relaxation showed a trend toward an increase at day 10 and a significant increase at day 42 in the IL-10 group relative to that in controls., Conclusions: This study demonstrates successful gene transfer of IL-10 into adult murine patellar tendon using a lentiviral vector. Although the effects of overexpression of IL-10 on adult tendon healing have not yet been fully elucidated, the current study may help to further clarify the mechanisms of tendon injury and repair.

Rotator cuff tears frequently occur and can lead to pain and decreased shoulder function. Repair of the torn tendon back to bone is often successful in relieving pain, but failure of the repair commonly occurs. Post-operative activity level is an important treatment component that has received minimal attention for the shoulder, but may have the potential to enhance tendon to bone healing. The objective of this study was to investigate the effect of short and long durations of various activity levels on the healing supraspinatus tendon to bone insertion site. Rotator cuff tears were surgically created in Sprague-Dawley rats by detaching the supraspinatus tendon from its insertion on the humerus and these tears were immediately repaired back to the insertion site. The post-operative activity level was controlled through shoulder immobilization (IM), cage activity (CA), or moderate exercise (EX) for durations of 4 or 16 weeks. The healing tissue was evaluated utilizing biomechanical testing and a quantitative polarized light microscopy method. We found that activity level had no effect on the elastic properties (stiffness, modulus) of the insertion site at four weeks post injury and repair, and a decreased activity level had a positive effect on these properties at 16 weeks (IM>CA=EX). Furthermore, a decreased activity level had the greatest positive effect on these properties over time (IM>CA=EX). The angular deviation of the collagen, a measure of disorganization, was decreased with a decrease in activity level at 4 weeks (IM

Rotator cuff tendon tears are one of the most common shoulder injuries. Although surgical repair is typically beneficial, re-tearing of the tendons frequently occurs. It is generally accepted that healing is worse for chronic tears than acute tears, but the reasons for this are unknown. One potential cause may be the large tensions that are sometimes required to repair chronically torn tendons back to bone (i.e., repair tension). Therefore, the objective of this study was to utilize an animal model of chronic rotator cuff repairs to investigate the role of increased repair tension on tendon to bone healing. We hypothesized that an increase in repair tension would be related to detrimental changes to the healing insertion site. To test this hypothesis, the supraspinatus tendon of rats was surgically detached and then repaired immediately or after a delay of 2, 4, or 16 weeks. The repair tension was measured using a tensiometer and the mechanical properties, collagen organization, and protein expression of the healing insertion site were evaluated 4 and/or 16 weeks following repair. We found that the repair tension increased with time following detachment, and was related to a decrease in the failure properties and viscoelastic peak stress and an increase in cross-sectional area and stiffness of the insertion site. Therefore, repair tension should be minimized in the clinical setting. Future studies will include additional animal model studies involving the relationship between tension and muscle properties and a clinical study investigating the role of repair tension on repair failure.

We present a prospective study of impaction grafting using collared textured stems in femurs with massive defects (defined as requiring >150 cm(3) of cancellous allograft). Eighteen hips were followed for a minimum of 2 years. Average Harris hip scores increased from 50 preoperatively to 83 at most recent follow-up. Seventeen hips were functioning well at the time of most recent follow-up and exhibited no stem subsidence or aseptic loosening. One hip was associated with visible subsidence and required further revision. Single-photon emission computed tomography analyses performed at an average of 37 months indicated active graft reorganization in all cases studied. Impaction allografting with collared textured stems for massive defects demonstrates good intermediate-term clinical results and may be a useful alternative to allograft stem composites and megaprostheses.

Rotator cuff tears occur frequently and can cause significant pain and reduced shoulder function. A high percentage of patients are satisfied after surgical repair of rotator cuff tears, but a smaller percentage of patients with chronic tears continue to have pain and poor shoulder function. This may be partly attributable to an increase in the repair tension, the force required at repair to reappose the tendon to its original insertion site on the humerus. Increases in repair tension have been shown to occur for long-standing ruptures of the supraspinatus tendon, but the precise tension at various times after injury are unknown. Therefore, the objective of the current study was to determine the repair tension at various times after a rotator cuff tear. This was achieved by creating a full-thickness supraspinatus tendon tear in a rat model and measuring the mechanical characteristics of the musculotendinous unit at 0, 2, 4, 9, and 16 weeks after injury. The repair tension rapidly increased initially after injury followed by a progressive, but less dramatic, increase with additional time. These findings suggest that rotator cuff tears should be repaired early in the clinical setting. Future studies will investigate the effect of repair tension on tendon to bone healing after repair.

Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repair of rotator cuff tendon tears depends on the time from onset of injury to the time of surgical repair. However, the effect of time from injury to repair remains poorly understood. A rat model was used to investigate the supraspinatus tendon organizational and mechanical property changes that occur with time post-injury to understand the natural injury response in the absence of repair. It was hypothesized that increased time post-injury would result in increased detrimental changes to tendon organizational and mechanical properties. Tendons were detached at the insertion on the humerus without repair and the quantitative organizational and mechanical properties were analyzed at 1, 2, 4, 8, and 16 weeks post-detachment. Tendon detachment resulted in a dramatic decrease in mechanical properties initially followed by a progressive increase with time. The quantitative collagen fiber orientation results provided corroborating support to the mechanical property data. Based on similarities in histology and mechanical properties to rotator cuff tears in humans, the animal model presented here is promising for future investigations of the tendon's natural injury response in the absence of repair.

Tears and tendinopathy of the gluteus medius and minimus are potentially underrecognized clinical sources of hip pain. Magnetic resonance imaging is useful in diagnosing gluteal tears. This entity is frequently a result of predisposing conditions but may arise spontaneously. This clinical problem should be considered in the differential diagnosis of patients presenting with acute hip pain. In this article, we report a case of spontaneous rupture of the gluteus medius and minimus tendons in a previously healthy patient with no prior hip symptoms.