Search

Laxity testing is an important part of the examination of any joint. In the shoulder, it presents unique challenges because of the complexity of the interactions of the glenohumeral and scapulothoracic joints. Many practitioners believe that laxity testing of the shoulder is difficult, and they are unclear about its role in evaluation of patients. The objectives of the various laxity and instability tests differ, but the clinical signs of such tests can provide helpful information about joint stability. This article summarizes the principles of shoulder laxity testing, reviews techniques for measuring shoulder laxity, and evaluates the clinical usefulness of the shoulder laxity tests. Shoulder laxity evaluation can be a valuable element of the shoulder examination in patients with shoulder pain and instability. [ABSTRACT FROM AUTHOR]

The development and successful clinical application of suture anchors and tacks have revolutionized the surgeon's ability to secure soft tissues to bone via open or arthroscopic surgical techniques. When used carefully and with proper technique, these devices provide viable options for the repair and reconstruction of many intra-articular and extra-articular abnormalities in the shoulder, including rotator cuff tears, shoulder instability, and biceps lesions that require labrum repair or biceps tendon tenodesis. Like many technologies, however, the successful application of these devices requires an understanding of the biology and biomechanics that affect their use in the shoulder as well as knowledge of the factors that can affect subsequent clinical outcomes, including complications. [ABSTRACT FROM AUTHOR]

BACKGROUND: Prevalence and clinical significance of partial tears of the subscapularis tendon have not been widely studied. PURPOSE: To determine prevalence of and clinical factors associated with partial tears of the subscapularis tendon at arthroscopy. STUDY DESIGN: Case control study. METHODS: During arthroscopic procedures on 314 consecutive shoulders, the arthroscopically visible portion of the subscapularis tendon was probed. Patients with and without partial tears were compared for prospectively identified variables. RESULTS: Partial tears were found in 60 of the 314 patients (19%). Increasing age and dominant arm involvement were significant variables for partial tears. Significantly associated factors included supraspinatus tendon tears (54 of 60; 90%), rotator cuff disease (44 of 60, 73%), and posterosuperior labral fraying (34 of 47, 72%). Increasing age, dominant arm involvement, and coexisting infraspinatus tendon tears were strong independent risk factors for partial tears. CONCLUSION: Partial tears of the subscapularis tendon are not uncommon findings during shoulder arthroscopic procedures and are associated with extensive rotator cuff disease. They do not appear to be associated with glenohumeral instability, but a possible association with atypical forms of instability (subclinical or superior instability) cannot be excluded by this study. The absence of a significant association between the lesion and specific subjective symptoms or physical findings suggests that caution should be taken when attributing a specific symptom to this condition. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous authors have suggested that the axillary nerve should be explored or palpated during all anterior shoulder stabilization procedures. OBJECTIVE: The goal of this study was to document the axillary nerve injury rate in a cohort of patients who had undergone anterior shoulder stabilization without axillary nerve dissection. HYPOTHESIS: Use of a subscapularis muscle-splitting approach by using a retractor along the scapular neck does not result in significant risk of injury to the axillary nerve, and exploration of the axillary nerve is not necessary using this approach. STUDY DESIGN: Prospective cohort study. METHODS: One hundred and twenty-eight anterior stabilizations were performed with a subscapularis muscle-splitting approach that has been previously described. In all cases a retractor was placed along the inferior scapular neck to protect the axillary nerve. The axillary nerve was not exposed or palpated in any case. All patients were evaluated on the 1st postoperative day and again within 10 days for symptoms of axillary nerve palsy, including sensory loss and return of muscle function. One patient (0.8%) had paresthesia in an axillary nerve distribution; recovery occurred without the need for electromyography or other interventions. There were no clinically detected cases of axillary nerve motor dysfunction. CONCLUSIONS: Routine exposure of the axillary nerve is not necessary during anterior stabilization procedures using a subscapularis muscle-splitting approach if proper precautions are taken to protect the nerve. Other techniques of anterior stabilization may require exposure of the axillary nerve. [ABSTRACT FROM AUTHOR]

During the last 3 decades, arthroscopy has revolutionized the way knee surgery is performed. The indications and the applications of arthroscopic procedures in the knee joint have enormously increased with the improvement in surgical technique and advent of new arthroscopic equipment. The use of arthroscopic techniques has led to a significant decrease in morbidity for the patient with intraarticular abnormalities, in terms of both diagnosis and surgical correction. Even though knee arthroscopy is a minimally invasive procedure with relatively low morbidity, it is not without risk of complications, of which neurovascular complications are among the most serious and devastating. The reported incidence of neurovascular complication is low, but it may be underestimated. Many neurovascular complications that occur are preventable with a thorough understanding of neurovascular anatomy, good preoperative and intraoperative planning, and attention to the details of basic techniques and the equipment used for the procedure. It is imperative that the surgeon who is performing arthroscopy be aware of these neurovascular complications, recognize them as early as possible, and initiate further evaluation and treatment as expeditiously as possible. In this article, the causes, management, prevention, and medicolegal implications of neurovascular complications of knee arthroscopy are reviewed. [ABSTRACT FROM AUTHOR]

Iatrogenic brachial plexus injury is an uncommon but potentially severe complication of shoulder reconstruction for instability that involves dissection near the subscapularis muscle and potentially near the brachial plexus. We examined the relationship of the brachial plexus to the glenoid and the subscapularis muscle and evaluated the proximity of retractors used in anterior shoulder surgical procedures to the brachial plexus. Eight fresh-frozen cadaveric shoulders were exposed by a deltopectoral approach. The subscapularis muscle was split in the middle and dissected to reveal the capsule beneath it. The capsule was split at midline, and a Steinmann pin was placed in the equator of the glenoid rim under direct visualization. The distance from the glenoid rim to the brachial plexus was measured with calipers with the arm in 0 degrees, 60 degrees, and 90 degrees of abduction. The brachial plexus and axillary artery were within 2 cm of the glenoid rim, with the brachial plexus as close as 5 mm in some cases. There was no statistically significant change in the distance from the glenoid rim to the musculocutaneous nerve, axillary artery, medial cord, or posterior cord with the arm in various degrees of abduction. Retractors placed superficial to the subscapularis muscle or used along the scapular neck make contact with the brachial plexus in all positions tested. [ABSTRACT FROM AUTHOR]

One hundred twelve practicing members of the American Shoulder and Elbow Surgeons in the United States and Canada were surveyed regarding use of weighted views of the acromioclavicular joint. They were also asked about treatment for hypothetical patients seen in the emergency department or office with grade II or III acromioclavicular separations. One hundred five physicians (94%) responded to the survey. Eighty-five members (81 %) did not recommend obtaining weighted views in the emergency department. Sixty members (57%) did not use weighted views, and the majority commented that weighted views had no influence on their decision-making regarding treatment. Forty-five members (43%) used weighted views, but most did not use the results of this test to determine surgical intervention. Physicians recommending weighted views averaged 21 years of practice, compared with 16 years for those who did not obtain weighted views. Only nine physicians (9%) had changed treatment on the basis of weighted views. The patient's arm dominance, work, or athletic status did not influence most surgeons' decision to perform surgery when weighted views revealed a grade III separation. We found no correlation between obtaining weighted views and performing surgical reconstruction for patients with grade III acromioclavicular separations. [ABSTRACT FROM AUTHOR]

We evaluated the frequency of posterior subluxations on physical examination of athletes who had no symptoms of shoulder injuries and correlated the findings with other measures of joint laxity. During routine sports physical examinations, 356 shoulders in 178 athletes were examined for posterior subluxation and graded as either positive or negative for subluxation. Sulcus signs were performed and graded as I (<1.0 cm), II (1.0 to 1.5 cm), or III (>1.5 cm). Standard hyperlaxity tests of other joints were used to measure general ligamentous laxity. Statistical analysis included the Student's t-test and chi-square analysis (P < 0.05). Overall, 55% of the shoulders could be subluxated posteriorly. More female shoulders (65%) than male shoulders (51%) could be subluxated posteriorly. Ten percent of the athletes had asymmetrical posterior shoulder laxity. Men had statistically significant less inferior translation (sulcus signs of grade I, 49%; grade II, 46%; grade III, 3%) than women (grade I, 36%; grade II, 54%; grade III, 9%). Five percent of the shoulders had posterior subluxation and a grade III sulcus sign. Asymptomatic posterior subluxation present at physical examination may represent normal laxity and may not indicate pathologic instability. [ABSTRACT FROM AUTHOR]

The histologic characteristics of the deltoid muscle attachment to nine cadaveric acromia were studied using light microscopy. The deltoid muscle attaches to the anterior and lateral acromion primarily by direct tendinous attachment. The muscle attaches to the dorsal side of the acromion by periosteal fiber attachment. In the specimens studied, a hypothetical acromioplasty of 4 mm would release, on average, 41% of the direct fiber attachment, and a 6-mm acromioplasty would release 69% for all zones examined histologically. The functional and clinical effects of these findings are not known, but the deltoid muscle would be released by arthroscopic acromioplasty in areas where bone is removed. [ABSTRACT FROM AUTHOR]

Overhand throwing requires contributions from and interaction between all limb segments. Most previous investigations have concentrated on the throwing arm itself, yet poor mechanics at the arm may originate in the lower extremities. Multicomponent ground-reaction forces of both the push-off and landing limbs were measured in six collegiate and one high school level baseball pitchers. Full body kinematics were simultaneously recorded to correlate phases in the pitching cycle with the force data. Pitchers were found to generate shear forces of 0.35 body weight in the direction of the pitch with the push-off leg and to resist forces of 0.72 body weight with the landing leg. Wrist velocity was found to correlate highly with increased leg drive. This study validates the clinical impression that the lower extremity is an important contributor to the throwing motion. Based on this study, strengthening of the lower extremities could be inferred to be important both to enhance performance and to avoid injury. [ABSTRACT FROM AUTHOR]

Background: Despite the increasing use of biceps tenodesis, there is a lack of consensus regarding optimal implant choice (suture anchor vs interference screw) and implant placement (suprapectoral vs subpectoral)., Purpose/hypothesis: The purpose was to determine the associations of procedural parameters with the biomechanical performance of biceps tenodesis constructs. The authors hypothesized that ultimate failure load (UFL) would not differ between sub- and suprapectoral repairs or between interference screw and suture anchor constructs and that the number of implants and number of sutures would be positively associated with construct strength., Study Design: Meta-analysis., Methods: The authors conducted a systematic literature search for studies that measured the biomechanical performance of biceps tenodesis repairs in human cadaveric specimens. Two independent reviewers extracted data from studies that met the inclusion criteria. Meta-regression was then performed on the pooled data set. Outcome variables were UFL and mode of failure. Procedural parameters (fixation type, fixation site, implant diameter, and numbers of implants and sutures used) were included as covariates. Twenty-five biomechanical studies, representing 494 cadaveric specimens, met the inclusion criteria., Results: The use of interference screws (vs suture anchors) was associated with a mean 86 N-greater UFL (95% CI, 34-138 N; P = .002). Each additional suture used to attach the tendon to the implant was associated with a mean 53 N-greater UFL (95% CI, 24-81 N; P = .001). Multivariate analysis found no significant association between fixation site and UFL. Finally, the use of suture anchors and fewer number of sutures were both independently associated with lower odds of native tissue failure as opposed to implant pullout., Conclusion: These findings suggest that fixation with interference screws, rather than suture anchors, and the use of more sutures are associated with greater biceps tenodesis strength, as well as higher odds of native tissue failure versus implant pullout. Although constructs with suture anchors show inferior UFL compared with those with interference screws, incorporation of additional sutures may increase the strength of suture anchor constructs. Supra- and subpectoral repairs provide equivalent biomechanical strength when controlling for potential confounders.

Background: Biomechanical cadaveric studies of rotator cuff repair (RCR) have shown that transosseous equivalent and double-row anchored repairs are stronger than other repair constructs., Purpose: To identify technical and procedural parameters that most reliably predict biomechanical performance of RCR constructs., Study Design: Systematic review., Methods: The authors systematically searched the EMBASE and PubMed databases for biomechanical studies that measured RCR performance in cadaveric specimens. The authors performed a meta-regression on the pooled data set with study outcomes (gap formation, failure mode, and ultimate failure load) as dependent variables and procedural parameters (eg, construct type, number of suture limbs) as covariates. Stratification by covariates was performed. An alpha level of .05 was used., Results: Data from 40 eligible studies were included. Higher number of suture limbs correlated with higher ultimate failure load (β = 38 N per limb; 95% CI, 28 to 49 N) and less gap formation (β = -0.6 mm per limb; 95% CI, -1 to -0.2 mm). Other positive predictors of ultimate failure load were number of sutures, number of mattress stitches, and use of wide suture versus standard suture. When controlling for number of suture limbs, we found no significant differences among single-row anchored, double-row anchored, transosseous equivalent, and transosseous repairs. Higher number of suture limbs and transosseous equivalent repair both increased the probability of catastrophic construct failure., Conclusion: This study suggests that the number of sutures, suture limbs, and mattress stitches in a RCR construct are stronger predictors of overall strength than is construct type. There is a need to balance increased construct strength with higher risk of type 2 failure.

Background: Diagnosing superior labrum anterior and posterior (SLAP) lesions through physical examination remains challenging. The dynamic labral shear test (DLST) has been shown to have likelihood ratios (LRs) of 31.6 and 1.1 for diagnosing SLAP lesions., Purpose: To determine the clinical utility of the DLST for diagnosing SLAP lesions., Study Design: Cohort study (diagnosis); Level of evidence, 2., Methods: This prospective, consecutive case series included 774 patients who underwent diagnostic arthroscopy and a preoperative DLST between 2007 and 2013. Patients were divided into 3 groups: 610 control patients with no SLAP lesion but with other abnormalities, 9 patients with isolated SLAP lesion (ISL), and 155 patients with concomitant SLAP lesion (CSL), who had a SLAP lesion and another shoulder abnormality. We determined sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), odds ratio (OR), and diagnostic accuracy (DA) of the DLST with and without other tests., Results: The DLST was positive for 242 of 610 controls (40%), 7 of 9 patients (78%) in the ISL group, and 88 of 155 patients (57%) in the CSL group. In the ISL group, the DLST had a sensitivity of 78%, specificity of 51%, PPV of 2%, NPV of 100%, OR of 3.58, and DA of 51%. In comparison, the ORs were 1.09 for the active compression test, 1.30 for the lift-off test, and 1.53 for the relocation test, which were not significantly different from each other. For diagnosing a SLAP lesion existing in a joint with other associated injury, the DLST had a sensitivity of 57%, specificity of 52%, PPV of 23%, NPV of 83%, OR of 1.4, and DA of 53%. Combining all 4 tests did not improve the OR for detecting ISLs or CSLs., Conclusion: The DLST is sensitive but not specific for detecting ISLs. With an OR of 3.58, the DLST is useful for diagnosing ISLs. However, in patients who have CSLs, the DLST is not as useful for diagnosing SLAP lesions.

Background: In part because of the perception that many injuries occur during collisions with the catcher at home plate, Major League Baseball (MLB) officials recently implemented rule changes to prevent these injuries. There is little research on the rate, type, and severity of injuries in MLB catchers., Purpose: To (1) determine the types and severity of injuries to catchers, (2) determine catchers' athlete exposure (AE) rate of injuries, and (3) assess the perception that catchers are at risk for career-ending injuries caused by home plate collisions., Study Design: Descriptive epidemiology study., Methods: The MLB Electronic Baseball Information System was queried for injuries in catchers during the 2001-2010 seasons categorized by cause (collision vs noncollision), diagnosis, and severity. All collision injuries were confirmed by reviewing publicly accessible records and news media. The injury exposure rate per 1000 AEs was calculated, and the rate of injury, associated days on the disabled list (DL), and injury severity were determined on the basis of cause and location of injury. Poisson regression was used to compare rates among seasons, and significance was set at P < .05., Results: During the study period, 134 injuries were sustained, resulting in 6801 days lost. The mean time on the DL was 50.8 days (range, 15-236). The average injury rate was 2.75 injuries per 1000 AEs (range, 0.82-5.14). Of those 134 injuries, 20 were collision injuries. Collision injuries resulted in a mean of 39 days (range, 15-93) of DL time, compared with 53 days for noncollision injuries (range, 15-236), which was not a significant difference. No collision injury was career ending. Noncollision injuries more commonly resulted in >100 days on the DL compared with collision injuries (P = .049)., Conclusion: Study findings indicated that (1) the most common type of injury to catchers was noncollision injury, (2) the rate of injuries to catchers is lower than previously reported rates for other player positions, and (3) this study did not support the perception that collision injuries are a frequent cause of career-ending injury to catchers., (© 2015 The Author(s).)

Background: Previous studies of the reliability of classifications for superior labral anterior and posterior (SLAP) lesions suggest that intraobserver/interobserver reliability is poor., Purpose: The goals were to (1) evaluate intraobserver/interobserver reliability of the Snyder classification of labrum tears among experienced surgeons, (2) determine the effect of simplifying that classification into normal versus abnormal labrums, (3) determine the reliability of subdividing type II SLAP lesions, and (4) evaluate the effect of videotape quality on diagnostic confidence., Study Design: Cohort study (diagnosis); Level of evidence, 3., Methods: At 2 separate times, 5 experienced shoulder surgeons (all >10 years of practice) evaluated 90 videotapes of shoulder arthroscopy performed for SLAP lesions to identify lesion type, to grade video quality, and to determine degree of confidence in diagnosis. The results were compared for intraobserver reliability (κ analysis) and interobserver reliability (intraclass correlation coefficients) and effect of video quality on diagnostic confidence. Significance was set at P < .05., Results: When the choices were normal labrum or the 4 types of SLAP lesions, the intraobserver agreements (mean κ, 0.670) and interobserver agreements (mean correlation, 0.804) were substantial. When the labrums were divided into normal (normal and type I) and abnormal (types II-IV), the intraobserver agreements (mean κ, 0.792) and interobserver agreements (mean correlation, 0.648) were substantial. When the 3 type II SLAP lesion subvariants were evaluated, the intraobserver agreement (mean κ, 0.598) was moderate, and the interobserver agreement (mean correlation, 0.804) was substantial. The confidence of the diagnosis was highly correlated with the perceived video quality (average Pearson correlation, 0.718; P < .01). Repeated measures analysis showed a significant relationship between confidence and quality (parameter estimate, 0.732; standard error, 0.021; P < .01) adjusting for rater and review., Conclusion: For experienced shoulder surgeons, the Snyder classification is a reliable system for identifying SLAP lesions.

Although suture anchor complications after arthroscopic shoulder surgery are uncommon, they can be devastating, such as articular cartilage or bone loss secondary to a dislodged or prominent suture anchor. Proper insertion of the anchor is the most important factor in the prevention of this complication, but if a complication occurs, prompt recognition and treatment are important to prevent damage to the shoulder. The goals were to (1) discuss strategies for preventing or dealing with dislodged or prominent suture anchors and (2) introduce techniques for removal of these implants.

Background: The accuracy of the physical examination for tears of the long head of the biceps remains controversial., Purpose: The goals were 1) to characterize the occurrence of partial tears of the long head of the biceps tendon in a group of consecutive patients, and 2) to analyze the diagnostic value of various clinical tests for pathologic lesions of the proximal biceps tendon., Study Design: Cohort study (diagnosis); Level of evidence, 2., Methods: Of 847 consecutive patients who underwent arthroscopic procedures for a variety of shoulder conditions, 40 were found at the time of arthroscopy to have partial biceps tendon tears. The average age of these 24 men and 16 women was 59 years (range, 18-83). Preoperative physical examinations had included 9 commonly used tests for shoulder examination. Statistical analysis included sensitivity, specificity, negative predictive value, positive predictive value, and likelihood ratios for these tests., Results: The prevalence rate of partial tears was 5% (40/847) of all arthroscopic procedures. The most commonly associated conditions included rotator cuff tears (85% [34/40]) and anterior instability (7.5% [3/40]). Tenderness on palpation of the long head of the biceps tendon had a sensitivity of 53%, a specificity of 54%, and a likelihood ratio of 1.13. The sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios for Speed's test were 50%, 67%, 8%, 96%, and 1.51, respectively., Conclusion: In patients with rotator cuff abnormality, the diagnosis of partial biceps tears cannot be made reliably with existing physical examination tests. Diagnostic arthroscopy is recommended, if clinically indicated, for potential partial tears of the long head of the biceps tendon. The treating physician should be prepared to treat unsuspected tears of the long head of the biceps tendon at the time of surgery.

The use of suture anchors and tacks around the shoulder requires a thorough knowledge of the proper use of the devices and how to insert them. Although typically not technically demanding, suture anchors and tacks can present unique and frustrating challenges to the patient and the surgeon. These challenges can occur whether the procedure is performed via an open or arthroscopic approach, but knowledge of the potential challenges may optimize the surgical result and prevent complications. Complications can be categorized as technique-related or device-related issues (mechanical or biologic failure). Technique-related complications include problems with the delivery systems, anchor malpositioning, and suture management issues, such as knots not sliding. Device-related complications include implant fracture, migration secondary to poor fixation, synovitis from implant degradation, and osteolysis. This review describes the prevention of these and other complications, addresses the indications or need for intervention, and suggests potential solutions when intervention is indicated.

Background: With the failure of thermal capsulorrhaphy for shoulder instability, there have been concerns with capsular thinning and capsular necrosis affecting revision surgery., Purpose: To report the findings at revision surgery for failed thermal capsulorrhaphy and to evaluate the technical effects on subsequent revision capsular plication., Study Design: Case series; Level of evidence, 4., Methods: Fourteen patients underwent arthroscopic evaluation and open reconstruction for a failed thermal capsulorrhaphy. The cause of the failure, the quality of the capsule, and the ability to suture the capsule were recorded. The patients were evaluated at follow-up for failure, which was defined as recurrent subluxations or dislocations., Results: The origin of the instability was traumatic (n = 6) or atraumatic (n = 8). At revision surgery in the traumatic group, 4 patients sustained failure of the Bankart repair with capsular laxity, and the others experienced capsular laxity alone. In the atraumatic group, all patients experienced capsular laxity as the cause of failure. Of the 14 patients, the capsule quality was judged to be thin in 5 patients and ablated in 1 patient. A glenoid-based capsular shift could be accomplished in all 14 patients. At follow-up (mean, 35.4 months; range, 22 to 48 months), 1 patient underwent revision surgery and 1 patient had a subluxation, resulting in a failure rate of 14%., Conclusions: Recurrent capsular laxity after failed thermal capsular shrinkage is common and frequently associated with capsular thinning. In most instances, the capsule quality does not appear to technically affect the revision procedure.

Background: Interference screw fixation of the graft in anterior cruciate ligament reconstruction is considered the gold standard, but limited clinical experience suggests that transcondylar fixation is equally effective., Purpose: To compare transcondylar and interference screw fixation., Study Design: Ex vivo biomechanical study., Methods: Twenty pairs of unembalmed knees underwent anterior cruciate ligament reconstruction with patellar tendon autografts. In 1 knee of each pair, the bone plug was stabilized in the femoral tunnel with standard interference screws; in the other knee, transcondylar screws were used. Testing to failure occurred immediately or after 1000 cycles of sinusoidal loading (30 to 150 N) (20 paired reconstructions each). Fixation stiffness, strength, graft creep, displacement amplitude, and change in amplitude were measured and compared (repeated measures anaylsis of variance with Tukey test; P <.05)., Results: There was no significant difference in acute strength, maximum load within 3 mm, or stiffness between transcondylar fixation (410 +/- 164 N, 183 +/- 93 N, and 49.6 +/- 28 N/mm, respectively) and interference fixation (497 +/- 216 N, 206 +/- 115 N, and 61 +/- 37.8 N/mm, respectively). Similarly, there was no significant difference in cyclic strength, maximum load within 3 mm, or stiffness between transcondylar fixation (496 +/- 214 N, 357 +/- 82.9 N, and 110 +/- 27.4 N/mm, respectively) and interference fixation (552 +/- 233 N, 357 +/- 76.2 N, and 112 +/- 26.8 N/mm, respectively). Predominant modes of failure were bone plug pullout (transcondylar fixation) and tendon failure or bone plug fracture (interference fixation)., Conclusions: Transcondylar screw fixation of the patellar tendon autograft into the femoral tunnel performed mechanically as well as interference screw fixation., Clinical Relevance: The results suggest that transcondylar and interference screws provide similar fixation for anterior cruciate ligament reconstruction.

Purpose: Chronic acromioclavicular joint lesions are a common source of pain and disability in the shoulder. The goal of this study was to evaluate diagnostic values of physical tests for isolated, chronic acromioclavicular joint lesions., Study Design: A retrospective case-control study., Methods: Between 1994 and 2002, 35 patients underwent a distal clavicle excision for isolated acromioclavicular joint lesions. The results of 3 commonly used examinations for acromioclavicular joint lesions were calculated for sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy., Results: The cross body adduction stress test showed the greatest sensitivity (77%), followed by the acromioclavicular resisted extension test (72%) and active compression test (41%). The active compression test had the greatest specificity (95%). All tests had a negative predictive value of greater than 94%, but the positive predictive value was less than 30% for all tests. The active compression test had the highest overall accuracy (92%), followed by the acromioclavicular resisted extension test (84%) and the cross arm adduction stress test (79%). Combinations of the tests increased the diagnostic values for chronic acromioclavicular joint lesions., Conclusions: These tests have utility in evaluating patients with acromioclavicular joint pathologic lesions, and a combination of these physical tests is more helpful than isolated tests.

Background: Three tests (active compression, anterior slide, and compression rotation) are commonly used to diagnose superior labral anterior-posterior lesions., Hypothesis: We hypothesized that the accuracy, sensitivity, and specificity for these tests was less than that previously reported and that a click in the shoulder during manipulation was not specific for the study lesion., Study Design: Case-control study., Methods: The three tests were performed on 426 patients who subsequently underwent shoulder arthroscopy. The results of physical examination were compared with the arthroscopic findings and analyzed for sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy., Results: At arthroscopy, 39 patients had type II to IV lesions (study group); the remaining 387 patients had type I lesion or no lesion (control group). The incidences of positive results were not statistically different between the groups (P > 0.05). Our findings were as follows: most sensitive test, active compression (47%); most specific test, anterior slide (84%); highest positive predictive value, active compression (10%); highest overall accuracy, anterior slide test (77%); lowest overall accuracy, active compression test (54%). The presence of a click and the location of the pain were not reliable diagnostic indicators., Conclusions: The results of such tests should be interpreted with caution when considering surgery for a possible superior labral anterior-posterior lesion.

Background: Attenuation of the shoulder capsule has been noted during revision surgery for failed thermal capsulorrhaphy., Hypothesis: The attenuated capsule seen in patients who have undergone failed thermal capsulorrhaphy will show histologic characteristics distinguishing it from the capsule of normal shoulders and dislocating shoulders., Study Design: Case control study., Methods: The shoulder capsules were studied in 12 patients with traumatic anterior instability and in 7 patients who experienced recurrent instability after a thermal capsulorrhaphy. The capsules of six fresh-frozen cadavers with no shoulder lesions were used as controls., Results: Among patients who had a history of traumatic instability, a denuded synovial layer was present in 58%, subsynovial edema in 58%, increased cellularity in 25%, and increased vascularity in 83%. At the time of surgery, five of seven shoulders in the failed thermal capsulorrhaphy group (71%) were subjectively felt to be thin and attenuated. Denuded synovium was found in 100% of these patients, subsynovial edema in 43%, and changes in the collagen layer in 100%. Changes in the collagen layer in these patients included a "hyalinization" appearance in five cases (71%), increased collagen fibrosis in two cases (29%), and increased cellularity in two cases (29%)., Conclusions: There was no one characteristic observable on histologic evaluation that would explain the attenuation of the capsule in cases of failed thermal treatment. Morphologic collagen structure can be histologically abnormal for up to 16 months after thermal capsulorrhaphy., (Copyright 2002 American Orthopaedic Society for Sports Medicine)

During the last 3 decades, arthroscopy has revolutionized the way knee surgery is performed. The indications and the applications of arthroscopic procedures in the knee joint have enormously increased with the improvement in surgical technique and advent of new arthroscopic equipment. The use of arthroscopic techniques has led to a significant decrease in morbidity for the patient with intraarticular abnormalities, in terms of both diagnosis and surgical correction. Even though knee arthroscopy is a minimally invasive procedure with relatively low morbidity, it is not without risk of complications, of which neurovascular complications are among the most serious and devastating. The reported incidence of neurovascular complication is low, but it may be underestimated. Many neurovascular complications that occur are preventable with a thorough understanding of neurovascular anatomy, good preoperative and intraoperative planning, and attention to the details of basic techniques and the equipment used for the procedure. It is imperative that the surgeon who is performing arthroscopy be aware of these neurovascular complications, recognize them as early as possible, and initiate further evaluation and treatment as expeditiously as possible. In this article, the causes, management, prevention, and medicolegal implications of neurovascular complications of knee arthroscopy are reviewed.

A case of myotonia congenita in an adolescent athlete was presented. Although this is a rare condition unknown to many treating physicians, the key to diagnosis was provocation of the patient's symptoms of muscle "tightening" and "cramping" during sustained exercise. The diagnosis would have been missed in routine office examinations with the patient at rest. The stereotypic generalized myotonic signs and symptoms were provoked after the patient was asked to play 20 minutes of basketball during one of his office evaluations. The provocative or postexercise examination was critical to the diagnosis as the resting office examination was completely normal. The diagnosis was subsequently confirmed by EMG and genetic testing. Myotonia congenita should be considered in the differential diagnosis of athletes with exercise-induced muscle "stiffness" or "cramping," particularly if the course is protracted and initial examinations are unremarkable. A provocative exercise period can be used to make the diagnosis. Once the diagnosis is established, appropriate pharmacologic treatment may improve symptoms and allow return to daily activity without restriction.

The methods and materials for ACL reconstruction are important issues for the practicing orthopaedic surgeon. In this study a model was developed to study the biological and biomechanical characteristics of a patellar tendon autograft used for ACL reconstruction. Specifically it was hypothesized that since vascularity of these grafts reflects their "healthiness," strength and vascularity should be inversely related in the early period after implantation. Using an over the top technique, a patellar tendon graft was placed in three groups of dogs and studied at 37, 57, and 120 days. Vascularity of the grafts was measured using technetium-tagged red blood cells, and percent water by weight was determined by dessication. Tensile testing to failure was performed using an MTS machine. The grafts became more vascular, more hydrated, less stiff, and less strong (by 4 weeks) than controls. By 16 weeks the vascular response was subsiding but the grafts remained only 40% as strong as controls. Percent water increased significantly over controls for all time periods. Decrease in strength correlated poorly with vascularity but correlated well with increase in percent water. These findings suggest that the change in strength of an intraarticular ACL replacement relates more to a basic rearrangement of its collagen-ground substance relationships, and that vascularity may reflect the inflammatory response bringing about these changes. The model developed in this study serves as a basis for further studies, and the findings reveal important information about the behavior of ACL grafting materials.