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The purpose of this study was to describe the activity of eight shoulder muscles during the windmill fast-pitch softball throw. Ten collegiate female pitchers were analyzed with intramuscular electromyography, high-speed cinematography, and motion analysis. The supraspinatus muscle fired maximally during arm elevation from the 6 to 3 o'clock position phase, centralizing the humeral head within the glenoid. The posterior deltoid and teres minor muscles acted maximally from the 3 to 12 o'clock position phase to continue arm elevation and externally rotate the humerus. The pectoralis major muscle accelerated the arm from the 12 o'clock position to ball release phase. The serratus anterior muscle characteristically acted to position the scapula for optimal glenohumeral congruency, and the subscapularis muscle functioned as an internal rotator and to protect the anterior capsule. Although the windmill softball pitch is overtly different from the baseball pitch, several surprising similarities were revealed. The serratus anterior and pectoralis major muscles work in synchrony and seem to have similar functions in both pitches. Although the infraspinatus and teres minor muscles are both posterior cuff muscles, they are characteristically uncoupled during the 6 to 3 o'clock position phase, with the infraspinatus muscle acting more independently below 90 degrees. Subscapularis muscle activity seems important in dynamic anterior glenohumeral stabilization and as an internal rotator in both the baseball and softball throws. [ABSTRACT FROM AUTHOR]

Optimization of isoquinolinone PI3K inhibitors led to the discovery of a potent inhibitor of PI3K-γ (26 or IPI-549) with >100-fold selectivity over other lipid and protein kinases. IPI-549 demonstrates favorable pharmacokinetic properties and robust inhibition of PI3K-γ mediated neutrophil migration in vivo and is currently in Phase 1 clinical evaluation in subjects with advanced solid tumors.

Background: There is no consensus on the optimal surgical technique for recurrent patellofemoral instability. Despite many different surgical procedures discussed in the literature, there are few studies with long-term outcomes., Hypothesis/purpose: The purpose of this study was to compare subjective and objective preoperative data from patients with recurrent patellar instability and normal alignment to midterm and long-term outcomes after an arthroscopically assisted medial reefing technique. The hypothesis was that the previously reported successful outcomes at 60 months would be well maintained over time., Study Design: Case series; Level of evidence, 4., Methods: A total of 19 patients (20 knees) with recurrent patellar instability and normal bony anatomy underwent arthroscopically assisted medial reefing without lateral release. They were evaluated preoperatively and then at midterm (average, 63 months) and long-term (average, 142 months) follow-ups. Patients underwent a history assessment, physical examination, and radiographic evaluation. Outcomes evaluated included Lysholm and Tegner scores, subjective data, and examination and radiographic findings. Operative reports were reviewed for the presence of chondral lesions. Comparative statistics were utilized (P < .05)., Results: All patients were satisfied with their surgery results and would undergo the procedure again. There was 1 recurrent subluxation and no recurrent dislocations. Subjective symptom scores demonstrated significant improvement from preoperative to midterm and long-term follow-ups for pain, instability, and swelling. Both Lysholm and Tegner scores improved significantly from preoperative to midterm and long-term follow-ups. At long-term follow-up, 70% of the patients reported excellent or good results, 5 patients reported fair results, and 1 patient reported a poor result. However, Tegner activity scores decreased significantly from midterm to long-term follow-ups. Significant improvement from preoperative to midterm and long-term follow-ups was demonstrated in physical examination findings including decreases in patellar apprehension and patellar quadrant glide; however, there was no significant difference in retropatellar pain or range of motion. For radiographic measurements, the lateral patellofemoral angle was significantly improved from preoperative to midterm and long-term follow-ups. At long-term radiographic analysis, 5 knees (25%) had narrowing of the patellofemoral joint space, 10 knees (50%) revealed patellofemoral osteophytes, and 7 knees (35%) demonstrated a medial ossicle. The presence of preoperative chondral lesions resulted in significantly lower Lysholm and Tegner scores and increased findings of osteoarthritis at long-term follow-up., Conclusion: Arthroscopically assisted medial reefing, without lateral release, is an effective long-term treatment for patients with recurrent patellar instability and normal bony anatomy.

Phosphoinositide-3 kinase (PI3K)-δ and PI3K-γ are preferentially expressed in immune cells, and inhibitors targeting these isoforms are hypothesized to have anti-inflammatory activity by affecting the adaptive and innate immune response. We report on a potent oral PI3K-δ and PI3K-γ inhibitor (IPI-145) and characterize this compound in biochemical, cellular, and in vivo assays. These studies demonstrate that IPI-145 exerts profound effects on adaptive and innate immunity by inhibiting B and T cell proliferation, blocking neutrophil migration, and inhibiting basophil activation. We explored the therapeutic value of combined PI3K-δ and PI3K-γ blockade, and IPI-145 showed potent activity in collagen-induced arthritis, ovalbumin-induced asthma, and systemic lupus erythematosus rodent models. These findings support the hypothesis that inhibition of immune function can be achieved through PI3K-δ and PI3K-γ blockade, potentially leading to significant therapeutic effects in multiple inflammatory, autoimmune, and hematologic diseases., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background: It has been suggested that patellofemoral contact pressures and contact forces may be altered secondary to an opening wedge high tibial osteotomy, yet few data are available that quantify the effect of varying degrees of medial opening wedge osteotomy on the patellofemoral joint contact characteristics., Hypothesis: Opening wedge medial proximal tibial osteotomy will increase patellofemoral contact force and pressure., Study Design: Controlled laboratory study., Methods: Nine human cadaver knees were used. Pressure-sensitive film was placed in the suprapatellar pouch, leaving the patellar tendon and medial and lateral retinacula intact. The quadriceps tendon was attached to a materials testing machine along the axis of the femur, whereby a pulley mechanism generated 950 N of force. Patellofemoral contact characteristics were measured with pressure-sensitive film at 30°, 60°, 90°, and 120° of flexion for the native knee and after subsequent 10-mm and 15-mm medial opening wedge proximal tibial osteotomies. The film was analyzed with imaging software., Results: There was a statistically significant increase (P < .05) in mean contact pressure at 30° and 120° between the 10-mm osteotomy and native knee and across all flexion angles between the 15-mm osteotomy and native knee. Furthermore, a significant difference was seen in peak pressures when native knees were compared with 10-mm and 15-mm opening wedge osteotomies at all flexion angles., Conclusion: There was a significant increase in patellofemoral pressures at varying degrees of knee flexion after medial opening wedge proximal tibial osteotomies of only 10 mm; a larger osteotomy resulted in a greater increase., Clinical Relevance: When performing a medial opening wedge proximal tibial osteotomy, the surgeon should consider the negative effects of increased patellofemoral peak pressure.

Background: The outcome is unknown for 2 common bracing treatments utilized for patients with lateral epicondylitis. The purpose of this study was to compare the clinical outcomes of a wrist splint with that of a counterforce forearm strap for the management of acute lateral epicondylitis., Materials and Methods: Forty-two patients (44 elbows) received either a wrist extension splint (Group I-24 elbows) or a counterforce forearm strap (Group II-20 elbows). Measures on the Mayo Elbow Performance (MEP) and American Shoulder and Elbow Society (ASES) Elbow Assessment Form were collected prior to treatment and at 6 weeks. A total score was derived, utilizing the ASES Elbow Assessment, as was a score utilizing the standard scoring system for the MEP., Results: Group I's score derived from the ASES form improved 16 points and Group II's score improved 13 points. Group I's score on the MEP improved 13 points and Group II's score improved 12 points. There was no significant difference measured between the Groups with the ASES (P = .60) nor MEP (P = .63) scores. However, within the ASES derived score, pain relief was significantly better with the extension splint group (P = .027). No other variables were statistically significantly different., Discussion: Significant pain relief with the wrist extension splint may be due to improved immobilization of the wrist extensor muscles in a resting position., Conclusion: The wrist extension splint allows a greater degree of pain relief than does the forearm strap brace for patients with lateral epicondylitis., (Copyright 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)

IPI-504, a water-soluble ansamycin analogue currently being investigated in clinical trials, is a potent inhibitor of the protein chaperone heat shock protein 90 (Hsp90). Inhibition of Hsp90 by IPI-504 triggers the degradation of important oncogenic client proteins. In cells, the free base of IPI-504 hydroquinone exists in a dynamic redox equilibrium with its corresponding quinone (17-AAG); the hydroquinone form binding 50 times more tightly to Hsp90. It has been proposed recently that the NAD(P)H:quinone oxidoreductase NQO1 can produce the active hydroquinone and could be essential for the activity of IPI-504. Here, we have devised a method to directly measure the intracellular ratio of hydroquinone to quinone (HQ/Q) and have applied this measurement to correlate NQO1 enzyme abundance with HQ/Q ratio and cellular activity of IPI-504 in 30 cancer cell lines. Interestingly, the intracellular HQ/Q ratio was correlated with NQO1 levels only in a subset of cell lines and overall was poorly correlated with the growth inhibitory activity of IPI-504. Although artificial overexpression of NQO1 is able to increase the level of hydroquinone and cell sensitivity to IPI-504, it has little effect on the activity of 17-amino-17-demethoxy-geldanamycin, the major active metabolite of IPI-504. This finding could provide an explanation for the biological activity of IPI-504 in xenograft models of cell lines that are not sensitive to IPI-504 in vitro. Our results suggest that NQO1 activity is not a determinant of IPI-504 activity in vivo and, therefore, unlikely to become an important resistance mechanism to IPI-504 in the clinic.

Hypothesis: We hypothesized that both the AC joint capsule and CC ligaments are biomechanically robust structures in the anterior-posterior (AP) and superior-inferior (SI) planes with low loads, and that these ligaments provide essential function in AC joint stability., Materials and Methods: Anterior-posterior (AP) and superior-inferior (SI) AC joint translations were quantified in 6 cadaver matched pairs with AC joint compressions of 10N, 20N and 30N, and with translational loads of 10N and 15N. Either the AC joint capsule or CC ligaments were transected, and measurements were then repeated. Biomechanical characteristics of the remaining AC joint capsule or CC ligaments were compared., Results: There were significant increases in AP translation with the cut AC joint capsule, and significant increases in SI translation with the cut CC ligaments (P < 0.0001). Compression significantly decreased translation (P < 0.0001)., Discussion: Our study is supported by, and further develops, recent studies and anatomical knowledge. It offers two interpreted pieces of information for the sports medicine physician to consider for reconstruction of the AC joint. First, resection of the distal clavicle may have a detrimental effect. Second, repair of the AC joint capsule, in addition to the customarily repaired CC ligaments, appears to have a beneficial effect., Conclusion: The AC joint capsule is a robust anatomical structure that contributes significantly to the AC joint stability, especially in the AP plane. Compression increases stability., Level of Evidence: Basic science study.

Background: College football players sustain an average of 3 subconcussive blows to the head per game. Concussions correlate with decreases in standardized neurocognitive test scores. It is not known whether repetitive, subconcussive microtrauma associated with participation in a full season of collision sport affects neurocognitive test scores., Hypothesis: No difference exists between preseason, midseason, and postseason Standardized Assessment of Concussion (SAC) and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores when collegiate football players sustain subconcussive microtrauma from forceful, repetitive contact activity., Study Design: Case series; Level of evidence, 4., Methods: Fifty-eight members of a Division III collegiate football team who had no known concussion during the season voluntarily completed the SAC and ImPACT instruments preseason, midseason, and postseason. A repeated measures analysis of variance was used to compare the scores at the 3 time intervals (P < .05)., Results: No statistically significant decreases were found in overall SAC or ImPACT scores or in any of the domains or composites of the tests (P < .05) when preseason, midseason, and postseason scores were evaluated., Conclusions: ImPACT and SAC neurocognitive test scores are not significantly altered by a season of repetitive contact in collegiate football athletes who have not sustained a concussion., Clinical Relevance: A diminution in SAC or ImPACT scores in concert with clinical symptoms and findings should be interpreted as evidence of a postconcussive event.

Background: Patellofemoral instability in patients with normal alignment has been effectively treated with medial reefing procedures and a lateral release. Recent research suggests that a lateral release may not be necessary in patients without excessive patellar tilt., Hypothesis: Arthroscopically assisted medial reefing without lateral release is as effective as techniques with a lateral release reported in the literature., Study Design: Case series; Level of evidence, 4., Methods: Twenty-four patients (25 knees) were observed for an average of 60 months. Preoperatively, patients underwent a history, physical examination, and radiographic evaluation. At follow-up, a physical examination and radiographic evaluation were repeated. Preoperative and postoperative Lysholm and Tegner scores were calculated. A subjective questionnaire was also completed. Comparative statistics were used for the preoperative and postoperative scores (P < .05)., Results: Ninety-six percent (24/25) were satisfied with their results, and all patients would have the same procedure performed again. Subjective symptom scores improved significantly. Lysholm knee scores improved from an average of 54 to 91 (P < .001). Tegner activity level improved from an average of 3.3 to 6.2 (P < .001). Significant improvement was seen in patellar mobility, apprehension, and patellofemoral tenderness with compression. Range of motion, muscle atrophy, and tilt did not change significantly. Congruence angles improved from 4.4 degrees to -2.5 degrees (P = .009), lateral patellofemoral angles improved from 5.5 degrees to 8.7 degrees (P = .011), and lateral patellar displacement improved from 2.0 to 0.2 mm (P < .044). There were no recurrent dislocations or subluxations., Conclusion: Arthroscopically assisted medial reefing, without lateral release, is an effective treatment for patients with recurrent patellofemoral instability and normal alignment.

Background: Inappropriately sized tennis racket grip is often cited in the popular media as a risk factor for overuse injuries about the forearm and elbow. Currently, a hand measurement technique developed by Nirschl is commonly used by tennis racket manufacturing companies as the method for determining a player's "recommended" grip size., Hypothesis: Quarter-inch changes from that recommended by Nirschl in tennis racket grip size will have no significant effect on forearm muscle firing patterns., Study Design: Controlled laboratory study., Methods: Sixteen asymptomatic Division I and II collegiate tennis players performed single-handed backhand ground strokes with rackets of 3 different grip sizes (recommended measurement, undersized (1/4) in, and oversized (1/4) in). Fine-wire electromyography was used to measure muscle activity in extensor carpi radialis longus and brevis, extensor digitorum communis, flexor carpi radialis, and pronator teres. Repeated-measure analysis of variance was used for within-group comparisons, comparing different grips in specified phases for backhand ground strokes (P

Background: The optimal suture configuration for arthroscopic rotator cuff repairs is controversial. "Locked" suture configurations, which use a combination of simple and transverse suture loops, have demonstrated better fixation strength than have traditional simple and horizontal mattress techniques., Purpose: To compare traditional arthroscopic suture configurations to locked arthroscopic configurations in ability to resist gap formation under cyclic loading., Study Design: Controlled laboratory study., Methods: Crescent-shaped defects were created at the infraspinatus tendon insertion in 32 bovine shoulders. Four arthroscopic suture configurations were tested (8 specimens in each group): simple (group 1), horizontal mattress (group 2), locked mattress (group 3), and locked inverted mattress (group 4). A metal corkscrew suture anchor doubly loaded with No. 2 Fiberwire suture was used for the repairs. A cyclic loading protocol with application of forces from 10 to 180 N for a maximum of 2,500 cycles was used. The number of cycles required to form gaps of 5 mm and 10 mm was recorded., Results: The locked mattress configuration (group 3) outperformed all other groups in resisting 5-mm gap formation (P < .0001), requiring a mean of 628 cycles in comparison to 65, 193, and 197 cycles for groups 1, 2, and 4, respectively. Both locked configurations (groups 3 and 4) were superior to traditional simple and horizontal mattress configurations in resisting 10-mm gap formation., Conclusion: The locked mattress suturing technique (group 3) provided the most secure tendon fixation of all arthroscopic configurations tested., Clinical Relevance: The use of locked suture configurations for arthroscopic rotator cuff repairs may enhance tendon fixation and limit gap formation in the early postoperative period.

Purpose: The purpose of this study was to evaluate the level of contaminants on, as well as the quality of, reprocessed shaver blades., Methods: We assessed 7 new shaver blades and 27 shaver blades that had been reprocessed with mechanical cleaning, functional testing, and sterilization with ethylene oxide. A spectrophotometer measured the amount of nucleic acid and protein. The blade quality was assessed by photographing the blades with magnification and determining the percentage of damage present on each blade. A subset of shaver blades were then used to cut meniscal tissue, and the cut surface was measured for smoothness by image processing and automated laser scanning cytometry. In evaluation of the meniscus, for the subset of shavers, an image processing value of 1 indicates a smooth, straight line, and values lower than 1 reflect deviations in the cut surface (the closer the value is to 1, the smoother the surface). Laser scanning cytometry values indicate the percentage of irregularities in the cut surface (the lower the value is, the smoother the surface)., Results: Of the 27 reprocessed shaver blades, 13 (48%) had detectable levels of protein and 17 (63%) had detectable levels of nucleic acid. On the reprocessed shaver blades, protein levels ranged from 2.43 microg to 60 microg and nucleic acid levels ranged from 0.40 microg to 3.5 microg. No new shaver blade had contaminants. Twenty reprocessed shaver blades had been manufactured with teeth and could be evaluated for visible damage. Of these, 10 had 1% to 25% damage, 5 had 26% to 50% damage, 3 had 51% to 75% damage, and 2 had 76% to 100% damage. The new blades had no visible damage. Image processing revealed smoothness of the surface cut with new shaver blades, yielding values of 1 +/- 0.12, whereas the values for reprocessed shaver blades ranged from 0.62 +/- 0.02 to 1 +/- 0.07. Laser scanning cytometry values ranged from 3.3% to 7.1% for the new blades as compared with 5.8% to 20.0% for the reprocessed blades., Conclusions: Of the reprocessed shaver blades, 48% had detectable levels of protein and 63% had detectable levels of nucleic acid. All of the reprocessed blades visually evaluated showed some level of damage or wear, whereas no new blade had such damage. In addition, menisci cut with reprocessed shavers showed rougher edges than did menisci cut with new shavers., Clinical Relevance: To make an informed decision regarding the use of reprocessed shaver blades, surgeons will want to know the level of contamination on, and the quality of, reprocessed shaver blades.

Purpose: The purpose of this study was to compare chondroplasty performed with an ExoJet high-pressure fluid-driven burr (Mitek, Norwood, MA), a mechanical shaver, and a bipolar radiofrequency (RF) wand on articular cartilage-covered condyles taken from sheep cadavers that were induced to have an osteoarthritic-like condition, and corresponding healthy control tissue., Type of Study: Experimental designed animal cadaveric, biochemical, and histologic study., Methods: Sheep condyles were used as a source of articular cartilage. Femurs were extracted approximately 1 hour postmortem and a transverse section of the condyles was made. Half of the samples were treated to induce an osteoarthritic-like condition. The condyles were then subjected to chondroplasty performed with the ExoJet high-pressure fluid-driven burr, a mechanical shaver, and a bipolar RF wand under sterile saline solution by an experienced orthopaedic surgeon. Twenty cross-sections from each condyle were examined by confocal microscopy to measure smoothness and depth of tissue damage to the articular cartilage caused by each of the 3 instruments., Results: The ExoJet high-pressure fluid-driven burr and the bipolar RF wand left a smoother surface on the articular cartilage compared with the mechanical shaver. Additionally, the ExoJet fluid-burr caused slightly less tissue damage to the cartilage than the bipolar RF wand, both of which were less damaging than the shaver., Conclusions: Orthopaedists have multiple choices for surgical instruments used on cartilage. However, the effect on the integrity of the cartilage left remaining at the knee was previously unknown. Based on this study, a fluid-burr appears to leave the cartilage with a smaller zone of injury than does the RF wand or shaver. It also leaves the cartilage surface smoother than the shaver. During surgical procedures, minimizing cartilage breakdown and smooth remaining surfaces are desired because they minimize the vulnerable tissue to further destruction. A fluid burr leaves cartilage with less injury and with a smoother surface than do more traditional surgical instruments., Clinical Relevance: This information should help surgeons in their selection of currently available surgical instruments and should aid engineers in the design of future instruments that function to modify articular cartilage.

Purpose: The purpose of this study was to compare the quality of meniscal tissue cut with 3 different surgical instruments (traditional shavers, bipolar radiofrequency (RF) wands, and a high-pressure saline jet) and that of control menisci., Type of Study: Experimental design, biochemical and histologic study., Methods: Sixty samples of sheep menisci were separated into 4 groups. Three groups were shaved on the apical surface with the different instruments. The smoothness of the cut surfaces was evaluated visually by an orthopaedic surgeon and then scored by laser scanning cytometry and by line measurement analysis. The depth of tissue damage was measured by fluorescent cytochemistry. Means and standard deviations were calculated and comparative statistics used (P < .05)., Results: The edges cut by the saline jet and bipolar RF were significantly smoother when judged by the surgeon than those cut by traditional shaver. There was no significant difference between the saline jet and bipolar RF. There were no significant differences in smoothness when measured by laser scanning cytometry or by line measurement techniques. The control menisci had less depth of damage along the edge as measured by fluorescent cytochemistry than did any of the menisci cut with the instrument. The saline jet had significantly less depth of damage than did the shaver. No other significant differences existed between the instruments for depth of damage., Conclusions: The results of our investigation conclude that high-pressure saline instruments may cause less damage to residual meniscal tissue when compared with bipolar RF and shavers. Saline jets and bipolar RF also produce a smoother cut than shavers., Clinical Relevance: Surgeons may want to consider the degree of residual damage to meniscal tissue from the application of various surgical instruments. Saline jets may be a superior cutting instrument than RF or shavers when considering depth of residual damage and smoothness of residual meniscal edges.

The goal of this study was to describe the anatomic relationships present during the active compression test. Four pairs of cadaveric shoulders were positioned to simulate the active compression test. The shoulders were embedded in polyurethane and evaluated in the axial and coronal planes with a planer. In the axial plane, all internally rotated shoulders demonstrated contact between the lesser tuberosity and subscapularis tendon and the superior aspect of the glenoid and labrum. In the externally rotated position, there was no contact between the superior structures of the shoulder. In the coronal plane, the internally rotated specimens revealed contact between the supraspinatus tendon and the lateral aspect of the acromion. There was no contact between the supraspinatus tendon and the acromion when the shoulders were externally rotated in the coronal plane. The results demonstrate that the active compression test can be used to assist in the diagnosis of superior labrum anterior-posterior lesions as well as other shoulder pathology.

This study compared muscle activity and timing of gait phases during functional activities in 13 subjects with patellofemoral pain associated with lateral subluxation and in 11 subjects with healthy knees. Fine wire electromyography recorded activity in the vastus lateralis and vastus medialis oblique during walking and ascending and descending stairs. Subjects were filmed to divide the activities into phases and determine timing. The vastus medialis oblique and vastus lateralis had similar patterns during all activities. Subjects with patellofemoral pain had significantly increased activity in the vastus medialis oblique and vastus lateralis compared with the healthy subjects during the most demanding phases of the gait cycle, suggesting a generalized quadriceps weakness in the patients with patellofemoral pain. Timing differences were seen in walking and stair ascending with the subjects with patellofemoral pain spending significantly more time in stance compared with the healthy subjects. This may be an attempt to reduce the load on weak quadriceps. These data reflect a generalized quadriceps muscle weakness, rather than the prevailing theory of quadriceps muscle imbalance as an etiology of patellofemoral pain. Therefore, we support the practice of strengthening the entire quadriceps muscle group, rather than attempting to specifically target the vastus medialis oblique.

Eighty-three athletes with medial elbow instability underwent reconstruction of the anterior band of the ulnar collateral ligament with a muscle-splitting approach without transposition of the ulnar nerve. The purposes of this study were to describe postoperative neurologic outcomes in all 83 athletes and to describe the 2-year follow-up in 33 athletes. Postoperatively, 5% of this group had transient ulnar nerve symptoms, all of which resolved with nonoperative management. There were no reoperations for nerve dysfunction and no permanent nerve problems. At 2- to 4-year follow-ups, 93% of the highly competitive athletes who had not had a prior surgical procedure had an excellent result. All athletes, regardless of whether they had a prior procedure, were able to return to their sport. These surgical modifications to the ulnar collateral ligament reconstruction yielded a decreased postoperative complication rate and improved outcomes compared with the results of prior procedures.

The purpose of this study was to compare subjects with subacromial impingement and subjects with normal shoulders with respect to muscle activity. Fifteen subjects in each group were studied by means of fine-wire electromyography. The middle deltoid and rotator cuff muscles were evaluated during isotonic scaption from 30 to 120 degrees. Overall, the impingement group demonstrated decreased mean muscle activity in comparison with the group of normal subjects. The magnitude of diminished activity was statistically significantly different (P < .05) during the 30- to 60-degrees arc for the infraspinatus, subscapularis, and middle deltoid muscles; in addition, the infraspinatus muscle demonstrated significantly depressed activity during the 60- to 90-degrees arc. In the impingement group, the supraspinatus and teres minor revealed a diminution of muscle function in comparison with shoulders in the normal group; the difference was not significant. This study demonstrates that muscle activity in subjects with impingement is most notably decreased in the first arc of motion. Also of clinical relevance is the fact that the inferior force vector (from the infraspinatus and subscapularis) is less functional in subjects with impingement than is the superior compressive vector (from the supraspinatus). Thus, humeral head depression during the critical first portion of elevation may be insufficient in people with subacromial impingement.

Thirteen overhand-throwing athletes who failed at least 3 months of physical therapy while restricted from throwing and who demonstrated a positive modified relocation test at 90 degrees, 110 degrees, and/or 120 degrees were clinically and arthroscopically examined. On arthroscopic examination, all patients demonstrated articular surface pathology. Eleven patients had fraying of the undersurface of the rotator cuff, and 10 patients had fraying of the posterosuperior labrum. With 90 degrees shoulder abduction, 8 patients had rotator cuff contact with the posterosuperior labrum. When the shoulder was abducted to 110 degrees, all patients demonstrated such contact. At 120 degrees of abduction, 12 patients revealed contact. The presence or absence of pain during the modified relocation test correlated with the presence or absence of cuff contact with the posterosuperior labrum 79% of the time. Six patients had a positive modified relocation test at all levels of abduction. These patients included 2 with SLAP lesions, 1 with a Bankart lesion, and 1 with a complete tear of the rotator cuff.

Given the popularity of swimming and the high risk of injury associated with the sport, many clinicians come into contact with the swimmer's shoulder. This article describes the mechanism of injury, diagnostic tools, and subtle signs of injury for swimmer's shoulder. It focuses on conservative treatment for the injury, including methods for stretching and strengthening and eliminating acute inflammation.

The purpose of this study was to compare the effect of increasing loads and doubling speed on the deltoid and rotator cuff muscles during isotonic scapular plane abduction (scaption) with neutral humeral rotation. These muscles were studied in 16 volunteers with asymptomatic shoulders with the use of fine wire electromyography. The addition of load to the arm during scaption caused an increase in electromyographic activity during the first 90 degrees of motion. Furthermore electromyographic activity decreased during the final 30 degrees of motion with each increase in load. Doubling the speed caused an increase in electromyographic activity during the first 60 degrees of motion while causing a decrease in activity in the final 60 degrees. This study demonstrates the response of the rotator cuff and deltoid muscles to varying loads and speeds during the most basic shoulder motion. With the data obtained in this study, rehabilitation exercises and experimental shoulder models can be refined to reflect this more physiologic situation.

Summary: The purpose of this article is to describe the outcome of an arthroscopic examination and the pathology in symptomatic shoulders of 41 professional overhand throwing athletes. With the arm in the position of the relocation test, 100% of the subjects had either contact between the rotator cuff undersurface and the posterosuperior glenoid rim or osteochondral lesions. Other key findings included undersurface cuff fraying in 93%, posterosuperior labral fraying in 88%, and anterior labral fraying in 36% of the subjects. This study supports the concept of impingement of the posterior cuff undersurface with the posterosuperior glenoid rim in the overhand throwing athlete with shoulder pain.

The purpose of this study was to describe the extra- and intra-articular anatomic relationships present during the Neer and Hawkins tests. Nine fresh-frozen cadaveric shoulders were positioned in the impingement position described by Neer (n = 5) or that described by Hawkins (n = 4), embedded in polyurethane, and studied with the use of a cross-sectional technique. All shoulders placed in the Neer position demonstrated soft tissue contact with the medial acromion and contact between the articular surface of the rotator cuff tendons and the anterosuperior glenoid rim. Shoulders placed in the Hawkins position demonstrated consistent contact between soft tissues and the coracoacromial ligament. In all Hawkins positioned shoulders, contact between the articular surface of the rotator cuff tendons and the anterosuperior glenoid was observed. The subscapularis tendon was deformed by the coracoid in 1 of the Hawkins positioned specimens. Although factors inherent to human subjects such as edema and muscle tone may influence the anatomy, these provocative tests for subacromial impingement appear to elicit contact consistent with impingement.

The primary restraint preventing humeral head translation is the capsuloligamentous system. Muscle forces can also decrease translation; however, the timing and magnitude of muscle response has not been previously reported. Fine wire electromyographic analysis of the biceps long head, anterior deltoid, pectoralis major, latissimus dorsi, and rotator cuff muscles was performed after an anterior translation force was applied to 15 normal shoulders. The reflex response time (time to 5% maximal muscle test), the protection response time (time to 20% maximal muscle test), the duration of the protection response, and the magnitude of the protection response were calculated. The shoulder reaction data showed 2 consistent patterns. Activation of the anteriorly located muscles preceded the posteriorly located muscles, and the rotator cuff muscles fired with greater magnitude than the more peripherally located muscles.

Objective: To compare the fine wire electromyographic (EMG) firing patterns during static stretches in the biceps femoris, soleus, and gastrocnemius before and after warm-up as well as over time., Design: Experimental single group pretest-posttest design., Setting: Biomechanics research laboratory., Participants: Sixteen healthy volunteers 23 to 36 years of age with no history of lower extremity injury., Intervention: Subjects performed one hamstring stretch and four calf stretches for 90 seconds, bicycled for 30 minutes as a warm-up, and stretched again., Main Outcome Measure: EMG was recorded at time 0, 30, 60, and 90 seconds during the stretches before and after warm-up. Recorded values were normalized to EMG during maximum manual muscle testing (MMT). A two-way analysis of variance with repeated measures (p < 0.05) was done to compare EMG activity during stretching before and after warm-up as well as over time., Results: Low EMG activity was seen for all muscles (< 20% MMT). It was constant over the time of the stretch for all muscles, but it increased in the soleus during the bent knee stretch position. There was a statistically significant decrease in the EMG activity after the warm-up for the gastrocnemius using the traditional and heel off stretching positions and for the soleus using the heel off stretching position (p < 0.05). The biceps femoris EMG activity showed no significant differences before and after warm-up., Conclusions: EMG activity during static stretching was low. Overall, the EMG activity remained constant with time for a given stretch position. EMG of the soleus and gastrocnemius was significantly less after warm-up for some stretches, whereas the EMG activity of biceps femoris showed no differences before and after warm-up.

The purpose of this study was to describe the electromyographic (EMG) pattern and relative intensities of 8 shoulder muscles during the volleyball serve and spike in 15 professional or collegiate-level athletes. The EMG analysis was synchronized with high-speed cinematography to discern phases of the spike and serve. During the spike, the anterior deltoid and supraspinatus functioned together to elevate and place the humerus throughout all phases. During cocking the infraspinatus and teres minor acted together to rotate the humerus externally. In acceleration, however, these muscles behaved independently; activity of the teres minor remained high, whereas the activity of the infraspinatus declined. The anterior wall muscles functioned to decelerate the humerus during cocking and acted as internal rotators during acceleration. Muscle activities recorded for the serve followed similar patterns as those seen for the spike, but with lower amplitudes. These data illustrate the complex sequence of shoulder muscle activity necessary to play competitive volleyball.

This study compared the electromyographic activity of rotator cuff and scapular muscles between subjects with anterior instability and subjects with normal shoulders. Thirty-eight patients were studied; 23 had anterior instability that was subsequently surgically confirmed, and 15 had normal shoulders. Fine wire electrodes were inserted into the subscapularis (upper and lower portions), supraspinatus, infraspinatus, rhomboid, serratus anterior, and trapezius (upper and lower portions) muscles. Abduction, scapular plane abduction (scaption), and forward flexion were performed over the range of motion and later divided into 30 degrees intervals. In both abduction and scaption, the supraspinatus demonstrated significantly less electromyographic activity from 30 degrees to 60 degrees in shoulders with anterior instability compared with normal shoulders (p < 0.05). During all three motions, shoulders with anterior instability demonstrated significantly less electromyographic activity in the serratus anterior when compared with normal shoulders (p < 0.05). This occurred at 30 degrees to 120 degrees of abduction and at 0 degree to 120 degrees of scaption and forward flexion. None of the other muscles demonstrated significant differences. These differences during planar motions were similar to those demonstrated during challenging overhead sport motions. Early rehabilitation efforts should focus both on the rotator cuff and scapular muscles to establish smooth, coordinated shoulder motion.

This discussion and the three case examples illustrate different etiologies of shoulder problems in the golfer. Age and the mechanics of an individual swing are factors to consider when defining the core problem. In summarizing shoulder pain in the golfer, perhaps the key point is that a thorough patient evaluation is essential to diagnose the problem accurately. It is only with a specific and accurate diagnosis that an optimal treatment program can be designed, and successful outcomes will be the result.

In summary, a sport-specific exercise program for golfers includes warming up, stretching, strengthening, and cardiovascular conditioning. The goals of such a program incorporated with playing the game of golf are to optimize performance and prevent injuries. The integration of each of these components represents a well-balanced fitness approach to sport and enhances the enjoyment of the game.