Immobilization in External Rotation Reduces the Risk of Recurrence After Primary Anterior Shoulder Dislocation: A Meta-analysis

Background

The best method for nonsurgical treatment after primary dislocation of the shoulder is not clear. The efficacy of immobilization with the arm in external rotation (ER) compared with internal rotation (IR) remains controversial.

Purpose

To determine the efficacy of ER immobilization versus IR immobilization on recurrence rate after primary dislocation of the shoulder from the evidence of randomized controlled trials.

Study Design

Systematic review; Level of evidence, 2.

Methods

Electronic databases (MEDLINE [Ovid SP], PubMed, Web of Science, EBM reviews, and CINAHL) and available proceedings according to the abstracts of major international meetings related to or including shoulder injuries and trauma were used to search for randomized controlled trials. Two independent investigators determined eligibility and carried out data extraction from the selected studies.

Results

A total of 9 studies (817 patients) were selected for this meta-analysis. They included 668 male and 149 female patients, with a mean age ranging from 20.3 to 37.5 years. In the 9 pooled studies, the recurrence rate of shoulder dislocation was 21.5% (84/390) in the ER group versus 34.9% (130/373) in the IR group. ER immobilization significantly reduced the recurrence rate compared with IR immobilization (risk ratio, 0.56; P = .007). In the subgroup analysis of those immobilized full-time, ER immobilization was significantly more effective than IR immobilization in reducing the recurrence rate (risk ratio, 0.57; P = .01). In the subgroup analysis of age, ER immobilization was significantly more effective than IR immobilization in those aged 20 to 40 years but not in those younger than 20 years.

Conclusion

This meta-analysis demonstrates that ER immobilization reduces the recurrence rate after primary shoulder dislocation compared with IR immobilization in patients older than 20 years. When treating a patient with primary shoulder dislocation, the clinician should provide this information to the patient before a treatment method is selected.

Acute Effects of Weighted Baseball Throwing Programs on Shoulder Range of Motion

BACKGROUND

Baseball pitching injuries are increasing at an alarming rate. While weighted ball throwing programs may be effective at increasing pitching velocity, previous research has identified a 24% injury rate and a 3.3° increase in shoulder external rotation (ER) range of motion (ROM) after performing a 6-week program. However, previous research has not investigated, separately, the immediate effects of throwing underloaded and overloaded balls on ROM. The purpose of this study was to examine the acute effects of throwing differently weighted baseballs on shoulder ROM. By analyzing these differences, it may be possible to determine the specific weight range that may lead to the greatest increase in ROM and potential injury risk.

HYPOTHESIS

Throwing with weighted balls will result in an increase in shoulder ER ROM.

STUDY DESIGN

Randomized controlled trial.

LEVEL OF EVIDENCE

Level 2.

METHODS

A total of 16 male high school baseball pitchers agreed to participate in this study. The participants were (mean ± SD) 17.1 ± 1.0 years of age, 1.81 ± 0.09 m tall, and had a mass of 79.2 ± 11.1 kg. Each participant was tested on 3 different days, 1 week apart, with 3 different conditions in random order: (1) underload throwing, using regulation 5-oz baseballs and 4- and 2-oz balls; (2) overload throwing, using 5-, 6-, and 9-oz balls; and (3) extreme overload throwing, using 5-, 16-, and 32-oz balls. Each testing session began by measuring passive shoulder ROM (external rotation and internal rotation) using standard goniometric measurements. Participants then performed 3 throws with each weighted ball from 3 different positions (kneeling, rocker, and run-and-gun) for a total of 27 throws each test session. ROM measurements were repeated at the end of each test session. The effect of each throwing condition on ROM was compared from pre- to posttraining using a paired t test (P ≤ 0.05).

RESULTS

There was no significant difference in ER after throwing at underloaded weights. The overload condition showed a statistically significant increase of 3.3° in external rotation (P = 0.05). The extreme overload condition showed a statistically significant increase in ER of 8.4° (P < 0.001). There were no differences in internal rotation for any group.

CONCLUSION

A significant increase in shoulder ER was observed immediately after throwing overload weighted balls. This effect increased as the weights of the balls increased.

CLINICAL RELEVANCE

Throwing with overload weighted baseballs causes an immediate increase in shoulder ER ROM. It is unknown why these changes occur; however, the results may explain both the increase in velocity and injury rates previously observed from throwing weighted balls. The current study results may be used to develop more scientifically validated weighted ball programs. Heavier balls should be used with caution, and ROM should be monitored during implementation of these programs.

Teres major transfer to restore external rotation of shoulder in Erb palsy patients

BACKGROUND

The lack of external rotation and shoulder abduction as sequelae of obstetric brachial plexus palsy requires a release of the subscapularis muscle associated with tendon transfer of the internal rotator of the shoulder. The aim of this study was to present the results of a teres major transfer to the infraspinatus tendon.

METHODS

This study included 20 patients (9 boys and 11 girls) with a mean age of 3 years 8 months (range, 1.5-14 years). The average follow-up time was 42 months (range, 12-48 months) to determine whether external rotation weakness and internal rotation contracture sequelae were managed by anterior release of the subscapularis and teres major tendon transfer to the infraspinatus tendon.

RESULTS

We found marked improvement in shoulder abduction from 67° before surgery to 158° after surgery. We also found marked improvements in active external rotation from 8° before surgery to 85° after surgery and in passive external rotation from 0° preoperatively to 72° postoperatively. Two cases showed a loss of the last degrees of internal rotation, but this improved after physiotherapy.

CONCLUSIONS

Anterior release of the subscapularis tendon with a teres major transfer to the infraspinatus tendon significantly improves shoulder function in Erb palsy patients with internal rotation contracture.

Immobilization in external rotation vs internal rotation after shoulder dislocation: A systematic review and meta-analysis protocol

BACKGROUND

Dislocation of shoulder joint is the most prone to occurrence in all joints of human body, which is common in young people and has a high recurrence rate. It is mainly treated by conservative treatment. External rotation and internal rotation fixation are 2 common conservative therapies in clinical practice. Therefore, we conduct this systematic review and meta-analysis to evaluate the efficacy and safety of the 2 treatments.

METHODS

Nine electronic databases, PubMed, Web of Science, Embase, Cochrane Library, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov, CNKI, Wanfang Database and VIP Database, will be searched to find and include randomized controlled trials that meet inclusion criteria. RevMan5.3 will be used for data analysis and synthesis in this study. Subgroup analysis and sensitivity analysis will also be performed if necessary. In addition, GRADE will be used in the evaluation of evidence hierarchy.

RESULTS

This study will analyze and integrate the original evidence so far for clinical efficacy and safety of immobilization in external rotation and internal rotation on shoulder dislocation.

CONCLUSION

The conclusion of this study will conclude higher evidence and suggestions for the treatment of shoulder dislocation, so as to further guide clinical decision making.

PROSPERO REGISTRATION NUMBER

CRD42018106030.

The position of sling immobilization influences the outcomes of anatomic total shoulder arthroplasty: a randomized, single-blind, prospective study

BACKGROUND

To date, no studies have been published that have assessed the optimal position of sling immobilization after anatomic total shoulder arthroplasty for glenohumeral osteoarthritis.

METHODS

Thirty-six patients undergoing anatomic total shoulder arthroplasty for osteoarthritis were randomized to a neutral rotation sling versus an internal rotation sling. The primary outcomes assessed included the Disabilities of the Arm, Shoulder and Hand score; Western Ontario Osteoarthritis of the Shoulder score; Single Assessment Numeric Evaluation score; visual analog scale (VAS) scores for pain and satisfaction; compliance ratings; and radiographic and range-of-motion measurements. Primary outcomes were assessed at baseline and postoperatively at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year.

RESULTS

All patient-determined outcome scores for both groups revealed statistically significant improvements (P < .0001) from enrollment to final follow-up. There were statistically significant advantages to the neutral rotation sling group compared with the internal rotation sling group when we evaluated the improvements in (1) active external rotation (42° vs 25°, P = .03), (2) passive external rotation (44° vs 26°, P = .02), (3) passive horizontal adduction (7.7 cm vs 3.7 cm, P = .05), and (4) pain relief with passive adduction (VAS score, 6.2 cm vs 3.5 cm; P = .002). There was a trend toward greater improvements in the neutral rotation sling group when we measured (1) active horizontal adduction (8.3 cm vs 2.9 cm, P = .06) and (2) active internal rotation behind the back (18 cm vs 11.1 cm, P = .09). At 2 weeks, the neutral rotation sling group had significantly less night pain than the internal rotation sling group (mean VAS score, 18 mm vs 34 mm; P = .047).

CONCLUSIONS

Neutral rotation sling use after anatomic total shoulder arthroplasty resulted in statistically significant improvements in external rotation and adduction, as well as decreased night pain, compared with an internal rotation sling.

Effect of a 6-Week Weighted Baseball Throwing Program on Pitch Velocity, Pitching Arm Biomechanics, Passive Range of Motion, and Injury Rates

BACKGROUND

Emphasis on enhancing baseball pitch velocity has become popular, especially through weighted-ball throwing. However, little is known about the physical effects or safety of these programs. The purpose of this study was to examine the effects of training with weighted baseballs on pitch velocity, passive range of motion (PROM), muscle strength, elbow torque, and injury rates.

HYPOTHESIS

A 6-week weighted ball training program would result in a change in pitching biomechanical and physical characteristics.

STUDY DESIGN

Randomized controlled trial.

LEVEL OF EVIDENCE

Level 1.

METHODS

During the baseball offseason, 38 healthy baseball pitchers were randomized into a control group and an experimental group. Pitch velocity, shoulder and elbow PROM, shoulder strength, elbow varus torque, and shoulder internal rotation velocity were measured in both groups. The experimental group then performed a 6-week weighted ball throwing program 3 times per week using balls ranging from 2 to 32 ounces while the control group only used a 5-ounce regulation baseball. Both groups performed a strength training program. Measurements were then repeated after the 6-week period. Injuries were tracked over the 6-week training program and the subsequent baseball season. The effect of training with a weighted ball program was assessed using 2-way repeated-measures analysis of variance at an a priori significance level of P < 0.05.

RESULTS

Mean age, height, mass, and pretesting throwing velocity were 15.3 ± 1.2 years (range, 13-18 years), 1.73 ± 0.28 m, 68.3 ± 11 kg, and 30.3 ± 0.7 m/s, respectively. Pitch velocity showed a statistically significant increase (3.3%) in the experimental group ( P < 0.001). There was a statistically significant increase of 4.3° of shoulder external rotation in the experimental group. The overall injury rate was 24% in the experimental group. Four participants in the experimental group suffered elbow injuries, 2 during the training program and 2 in the season after training. No pitchers in the control group were injured at any time during the study.

CONCLUSION

Performing a 6-week weighted ball throwing program increased pitch velocity. However, the program resulted in increased shoulder external rotation PROM and increased injury rate.

CLINICAL RELEVANCE

Although weighted-ball training may increase pitch velocity, caution is warranted because of the notable increase in injuries and physical changes observed in this cohort.

Improved external rotation with concomitant reverse total shoulder arthroplasty and latissimus dorsi tendon transfer: A systematic review

BACKGROUND

In conjunction with reverse total shoulder arthroplasty (RSA), latissimus dorsi and teres major (LD-TM) transfer has been advocated in the setting of combined loss of elevation and external rotation. The purpose of this systematic review is to summarize the clinical outcomes following RSA with LD-TM transfer.

METHODS

A search of PubMed, EMBASE, CINAHL, Medline, and Cochrane databases was performed between January 1, 1990 and March 1, 2016 and included articles related to outcomes following RSA with LD-TM transfer. Primary outcomes of interest were constant score, shoulder range of motion, and patient satisfaction. Secondary outcomes of interest included subjective shoulder value, simple shoulder test, activities of daily living requiring external rotation, and visual analog pain score. Additional outcomes evaluated included complications and reoperations. Frequency-weighted values of outcome data were utilized.

RESULTS

Five level IV studies involving 98 shoulders met the inclusion criteria. The mean age of the cohort was 69.1 ± 5.19 years (range 47-85). RSA with LD-TM transfer was performed for rotator cuff arthropathy (94%) or proximal humerus fracture (6%). The average follow-up was 44.5 ± 10.38 months (range 12-105 months). The constant score improved from 28 to 65 ( p < 0.0005). Active external rotation improved from -7.4° to 22.9° ( p < 0.0005). There was a 22.4% overall complication rate, including dislocation (5.1%), infection (5.1%), and transient nerve palsy (3.4%).

CONCLUSION

Patients undergoing RSA with LD-TM transfer in the setting of loss of external rotation demonstrate reliable clinical improvements in shoulder function with complication rates which are comparable to RSA alone.

Anatomic study and electromyographic analysis of the teres minor muscle

BACKGROUND

The teres minor muscle is a focused topic on the treatment of massive rotator cuff tears and reverse total shoulder arthroplasty. Its precise anatomy and function have not been completely investigated. The purposes of this study were to anatomically investigate the muscle and analyze electromyographic (EMG) activities during shoulder motion.

METHODS

This anatomic study used 20 shoulders from deceased donors (mean age, 75.0 years). EMG data were recorded from 10 healthy volunteers (mean age, 21.7 years) during flexion, abduction, and external rotations at 0° of abduction, at 90° of abduction, and at 90° of flexion in their dominant arms synchronized with a computerized 3-dimensional motion analysis system.

RESULTS

The muscle in all specimens consisted of 2 distinct muscular bundles: the upper and lower portions. The upper portion attached to the round area of the greater tuberosity, and the lower portion inserted into the linear shaped area. Both portions were independent in their origins, insertions, and innervation. The muscle engaged force during each shoulder motion. EMG activities of abduction and the 3 forms of external rotation were similar. Maximal voluntary contraction in the 3 forms of external rotation was 32% in maximum external rotation in the neutral position, 25% in flexion, and 40% in abduction.

CONCLUSIONS

The teres minor consists of independent upper and lower portions. The muscle engages force in all ranges of 5 shoulder motions, and maximum external rotation in abduction is a reliable method to evaluate potential activity of the muscle.

Effects of a Short-Duration Stretching Drill After Pitching on Elbow and Shoulder Range of Motion in Professional Baseball Pitchers

BACKGROUND

A glenohumeral internal rotation (IR) deficit or a total rotational motion (IR plus external rotation [ER]) deficit in the throwing shoulder compared with the nonthrowing shoulder has been shown to increase the risk of shoulder and elbow injuries. After a pitching session, both IR and total rotational motion deficits have been shown to occur naturally for an extended period of time in asymptomatic pitchers, but it is unclear how to best control these deficits between pitching sessions. Purpose/Hypothesis: The purpose of this study was to determine whether performing a short-duration stretching/calisthenics drill after pitching will result in an increase in IR, ER, total rotational motion, and elbow extension in professional baseball pitchers. It was hypothesized that these shoulder and elbow passive range of motion (PROM) measurements would all decrease after pitching but would subsequently return to prepitching values after the short-duration stretching/calisthenics drill.

STUDY DESIGN

Controlled laboratory study.

METHODS

A convenience sample of 20 male professional baseball pitchers served as study participants. The following sequence of activities was performed for all participants: (1) a 5- to 10-minute dynamic warm-up consisting of running and light throwing, (2) elbow extension and IR and ER PROM measurements taken before pitching, (3) 40 full-effort pitches off the pitching mound, (4) 8 minutes of rest, (5) elbow extension and IR and ER PROM measurements taken after pitching, (6) a short-duration stretching/calisthenics drill (two-out drill), and (7) elbow extension and IR and ER PROM measurements taken after the two-out drill. A 1-way repeated-measures analysis of variance ( P < .05) was employed to assess differences in elbow extension, IR, ER, and total rotational motion in the 3 measurement conditions (prepitching, postpitching, and postdrill). To assess intrarater and interrater reliability, intraclass correlation coefficients (ICCs) were calculated, and the measurement error was calculated using the standard error of measurement (SEM).

RESULTS

Significant differences were observed among the 3 conditions for ER ( P = .002), IR ( P = .027), and total rotational motion ( P < .001), but there was no significant difference in elbow extension ( P = .117). Bonferroni post hoc analyses revealed (1) significantly greater ER during prepitching and postdrill versus the postpitching condition (94° ± 7° [prepitching] and 94° ± 8° [postdrill] vs 88° ± 8°; P = .010 and .005, respectively), (2) significantly greater IR during prepitching and postdrill versus the postpitching condition (36° ± 10° [prepitching] and 35° ± 9° [postdrill] vs 30° ± 10°; P = .034 and .043, respectively), and (3) significantly greater total rotational motion during prepitching and postdrill versus the postpitching condition (129° ± 13° [prepitching] and 129° ± 13° [postdrill] vs 119° ± 13°; P = .034 and .004, respectively). There were no significant differences in ER, IR, or total rotational motion between the prepitching and postdrill conditions ( P > .999 for all). The intrarater reliability (ICC_3,1) was 0.91 for ER (SEM, 1.3°) and 0.90 for IR (SEM, 1.9°), and the interrater reliability (ICC_2,1) was 0.81 for ER (SEM, 3.3°) and 0.77 for IR (SEM, 4.3°).

CONCLUSION

After a 40-pitch bullpen session, IR and ER PROM as well as total rotational motion were significantly lower than prepitching values; however, these deficits were restored back to their prepitching levels after the players performed the two-out drill, which may increase pitching performance and decrease the risk of shoulder and elbow injuries. More research is needed to test these hypotheses and assess the clinical efficacy of the two-out drill.

CLINICAL RELEVANCE

The findings from the current study will assist clinicians better understand the positive effects of performing a short duration stretching/calisthenics drill on shoulder internal and external rotation range of motion between innings while pitching during a baseball game.

The validity and reliability of ultrasound on identifying supraspinatus tears during passive external rotation from 0° to 30°: a pilot project

BACKGROUND

Controversy exists regarding how much external rotation should be allowed following rotator cuff repair. Clinicians may use ultrasound imaging (USI) to visualize the supraspinatus (SSp) tendon during passive external rotation. However, the validity and reliability of USI used to assess supraspinatus tendon gap formation during external rotation needs to be established prior to using this technique in patient cohorts.

METHODS

Ten subjects with magnetic resonance imaging (MRI) confirmation of full-thickness SSp tears were matched to 10 control subjects. Images of the SSp were obtained at 0°, 10°, 20° and 30° of external rotation by a blinded tester on two occasions to establish both validity and reliability of the measure.

RESULTS

Validity was established as 70% agreement between the USI and MRI confirmed SSp tear group; reliability was established at greater than 0.90 at all positions of external rotation measured.

CONCLUSIONS

USI may be used to detect SSp tears with 70% validity, and the technique is reliable in all positions of external rotation.

Immobilization in External Rotation Versus Internal Rotation After Primary Anterior Shoulder Dislocation: A Meta-analysis of Randomized Controlled Trials

BACKGROUND

The recurrence rate after primary anterior shoulder dislocation is high, especially in young, active individuals. Recent studies have suggested external rotation immobilization as a method to reduce the rate of recurrent shoulder dislocation in comparison to traditional sling immobilization.

PURPOSE

To assess and summarize evidence from randomized controlled trials on the effect of internal rotation versus external rotation immobilization on the rate of recurrence after primary anterior shoulder dislocation.

STUDY DESIGN

Meta-analysis.

METHODS

PubMed, MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and abstracts from recent proceedings were searched for eligible studies. Two reviewers selected studies for inclusion, assessed methodological quality, and extracted data.

RESULTS

Six randomized controlled trials (632 patients) were included in this review. Demographic and prognostic variables measured at baseline were similar in the pooled groups. The average age was 30.1 years in the pooled external rotation group and 30.3 years in the pooled internal rotation group. Two studies found that external rotation immobilization reduced the rate of recurrence after initial anterior shoulder dislocation compared with conventional internal rotation immobilization, whereas 4 studies failed to find a significant difference between the 2 groups. This meta-analysis suggested no overall significant difference in the rate of recurrence among patients treated with internal rotation versus external rotation immobilization (risk ratio, 0.69; 95% CI, 0.42-1.14; P = .15). There was no significant difference in the rate of compliance between internal and external rotation immobilization (P = .43). The Western Ontario Shoulder Instability Index scores were pooled across 3 studies, and there was no significant difference between the 2 groups (P = .54).

CONCLUSION

Immobilization in external rotation is not significantly more effective in reducing the recurrence rate after primary anterior shoulder dislocation than immobilization in internal rotation. Additionally, this review suggests that there is minimal difference in patients' perceptions of their health-related quality of life after immobilization in internal versus external rotation.

Electromyographic Analysis of the Shoulder Girdle Musculature During External Rotation Exercises

Background:

Implementation of overhead activity, a key component of many professional sports, requires an effective and balanced activation of the shoulder girdle muscles, particularly during forceful external rotation (ER) motions.

Purpose:

To identify activation strategies of 16 shoulder girdle muscles/muscle segments during common shoulder ER exercises.

Study Design:

Descriptive laboratory study.

Method:

Thirty healthy subjects were included in this study, and 16 shoulder girdle muscles/muscle segments were investigated (surface electrode: anterior, middle, and posterior deltoid; upper, middle, and lower trapezius; serratus anterior; teres major; upper and lower latissimus dorsi; and upper and lower pectoralis major; fine wire electrodes: supraspinatus, infraspinatus, subscapularis, and rhomboid major) using a telemetric electromyography (EMG) system. Five ER exercises (standing ER at 0° and 90° of abduction, with underarm towel roll, prone ER at 90° of abduction, side-lying ER with underarm towel) were studied. Exercise EMG amplitudes were normalized to EMG at maximum ER force in a standard position. Univariate analysis of variance and post hoc analysis applied on EMG activity of each muscle were used to assess the main effect of the exercise condition.

Results:

Muscular activity differed significantly among the ER exercises (P < .05 to P < .001). The greatest activation for anterior and middle deltoid, supraspinatus, upper trapezius, and serratus anterior occurred during standing ER at 90° of abduction; for posterior deltoid, middle trapezius, and rhomboid during side-lying ER with underarm towel; for lower trapezius, upper and lower latissimus dorsi, subscapularis, and teres major during prone ER at 90° of abduction; and for the clavicular and sternal part of the pectoralis major during standing ER with underarm towel.

Conclusion:

Key glenohumeral and scapular muscles can be optimally activated during specific ER exercises, particularly in positions that stimulate athletic overhead motions.

Clinical Relevance:

These results enable sports medicine professionals to target specific muscles during shoulder rehabilitation protocols while minimizing the effect of others, providing a foundation for optimal evidence-based exercise prescription. They also provide information for tailored muscle training and injury prevention in overhead sports.

High Ankle Sprains and Syndesmotic Injuries in Athletes

Treatment of athletes with ligamentous injuries of the tibiofibular syndesmosis can be problematic. The paucity of historic data on this topic has resulted in a lack of clear guidelines to aid in imaging and diagnosing the injury, assessing injury severity, and making management decisions. In recent years, research on this topic has included an abundance of epidemiologic, clinical, and basic science investigations of syndesmotic injuries that are purely ligamentous or associated with ankle fracture. Several classification systems can be used to classify ligamentous injury to the syndesmosis. These systems integrate clinical and radiographic findings but do not address the location of the injury or its severity. Injury to the syndesmosis can be purely ligamentous; however, many unstable syndesmotic injuries are associated with fractures. Nonsurgical management can be used for stable ligamentous injuries without frank diastasis, but surgical management, including screw or suture-button fixation, is indicated for fractures with unstable syndesmotic injuries.

Deficits in Glenohumeral Passive Range of Motion Increase Risk of Shoulder Injury in Professional Baseball Pitchers: A Prospective Study

BACKGROUND

Shoulder injuries from repetitive baseball pitching continue to be a serious, common problem.

PURPOSE

To determine whether passive range of motion of the glenohumeral joint was predictive of shoulder injury or shoulder surgery in professional baseball pitchers.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Passive range of motion of the glenohumeral joint was assessed with a bubble goniometer during spring training for all major and minor league pitchers of a single professional baseball organization over a period of 8 successive seasons (2005-2012). Investigators performed a total of 505 examinations on 296 professional pitchers. Glenohumeral external and internal rotation was assessed with the pitcher supine and the arm abducted to 90° in the scapular plane with the scapula stabilized anteriorly at the coracoid process. Total rotation was defined as the sum of internal and external glenohumeral rotation. Passive shoulder flexion was measured with the pitcher supine and the lateral border of the scapula manually stabilized. After examination, shoulder injuries and injury durations were recorded by each pitcher's respective baseball organization and reported to the league as an injury transaction as each player was placed on the disabled list.

RESULTS

Highly significant side-to-side differences were noted within subjects for each range of motion measurement. There were 75 shoulder injuries and 20 surgeries recorded among 51 pitchers, resulting in 5570 total days on the disabled list. Glenohumeral internal rotation deficit, total rotation deficit, and flexion deficit were not significantly related to shoulder injury or surgery. Pitchers with insufficient external rotation (<5° greater external rotation in the throwing shoulder) were 2.2 times more likely to be placed on the disabled list for a shoulder injury (P = .014; 95% CI, 1.2-4.1) and were 4.0 times more likely to require shoulder surgery (P = .009; 95% CI, 1.5-12.6).

CONCLUSION

Insufficient shoulder external rotation on the throwing side increased the likelihood of shoulder injury and shoulder surgery. Sports medicine clinicians should be aware of these findings and develop a preventive plan that addresses this study's findings to reduce pitchers' risk of shoulder injury and surgery.

Clinical performance of lateralized versus non-lateralized reverse shoulder arthroplasty: a prospective randomized study

BACKGROUND

Reverse shoulder arthroplasty (RSA) is an established therapeutic option in the treatment of cuff tear arthropathy (CTA). Recent studies have described a positive effect of lateralization of the center of rotation, especially on postoperative rotational function. The goal of this study is to compare the outcome of non-lateralized versus lateralized RSA with particular regard to rotational function in patients with CTA.

METHODS

Thirty-four patients underwent implantation of RSA either with lateralization (n = 17) or without lateralization (n = 17) by use of a 1-cm autologous bone graft ("bony increased offset") of the humeral head for CTA. Clinical outcomes were measured with the Constant score; the Disabilities of the Arm, Shoulder and Hand score; and the Activities of Daily Living Requiring External Rotation score, as well as measurement of external rotation and determination of the external rotation lag sign with the arm at the side and at 90° of abduction, at 1 year postoperatively and at final follow-up. Computed tomography scan evaluation was performed in all patients preoperatively and at 1 year postoperatively to assess preoperative fatty infiltration of the rotator cuff and bony integration of the graft postoperatively.

RESULTS

At final follow-up, all patients showed significantly increased functional results. There were no significant differences in the evaluated parameters. If patients with degenerative changes of the teres minor were excluded, the lateralized group showed significantly increased external rotation. Bony integration of the graft could be verified on postoperative computed tomography scans in all patients.

CONCLUSION

RSA with bony lateralization shows a trend toward improved external rotation in lateralized RSA, with a statistically significant improvement in external rotation in patients with an intact teres minor.

Arm Abduction Provides a Better Reduction of the Bankart Lesion During Immobilization in External Rotation After an Initial Shoulder Dislocation

BACKGROUND

Shoulder dislocation often recurs, especially in the younger population. Immobilization in external rotation, in which a Bankart lesion is displaced in the anterior, medial, and inferior directions, was introduced as a new method of nonoperative treatment, but its clinical efficiency is controversial. In terms of reducing the lesion, it is reasonable to incorporate not only external rotation, which makes the anterior soft tissues tight to push the lesion posteriorly and laterally, but also abduction, which makes the inferior soft tissues tight to push the lesion superiorly.

HYPOTHESIS

Abducting the arm during immobilization in external rotation will improve the reduction of a Bankart lesion.

STUDY DESIGN

Controlled laboratory study.

METHODS

There were 37 patients with initial shoulder dislocation enrolled in this study. After reduction, MRI was taken in 4 positions of the shoulder: adduction and internal rotation (Add-IR), adduction and external rotation (Add-ER), 30° of abduction and 30° of external rotation (Abd-30ER), and 30° of abduction and 60° of external rotation (Abd-60ER). On radial slices, the separation, displacement of the labrum, and opening angle of the capsule were measured.

RESULTS

Add-ER improved the reduction of the anterior labrum but not the inferior labrum when compared with Add-IR. Both Abd-30ER and Abd-60ER improved the reduction of the inferior labrum as compared with Add-IR. Furthermore, Abd-60ER improved the reduction more than Add-ER.

CONCLUSION

Among the 4 positions tested, Abd-60ER is the best position in terms of reducing the Bankart lesion.

CLINICAL RELEVANCE

Abducting the shoulder during immobilization in external rotation is demonstrated to improve the reduction of the Bankart lesion. Therefore, this position is expected to reduce the recurrence rate after initial dislocation of the shoulder. Future clinical trials are necessary.

The effect of humeral version on teres minor muscle moment arm, length, and impingement in reverse shoulder arthroplasty during activities of daily living

BACKGROUND

External rotation can be compromised after reverse total shoulder arthroplasty (RTSA). A functional teres minor (TM) is relatively common in patients with posterosuperior tears of the rotator cuff, and its function should be enhanced for better postoperative results. The aim of this study was to investigate how the version of humeral fixation can affect the TM rotational moment arm and muscle length as well as impingement after RTSA.

METHODS

A 3-dimensional shoulder model was used to describe RTSA. Four humeral fixation versions were tested: +20°, 0°, -20°, and -40° (+, anteverted; -, retroverted). TM rotational moment arm and length as well as impingement-free range of motion were calculated for a set of 3 simple clinical motions: (1) scapula plane abduction (0°-150°); (2) internal/external rotation with the arm in adduction; and (3) internal/external rotation with the arm in abduction. Six common activities of daily living were also evaluated.

RESULTS

An anteverted fixation maximized TM moment arms, but it also resulted in very short muscle length (compared with normal) and increased inferior impingement. In contrast, 40° humeral retroversion resulted in the longest TM muscle length, but it also showed the smallest moment arms and increased anterior impingement in some of the activities of daily living.

CONCLUSIONS

Even if TM external rotation moment arm is higher in RTSA than in a normal shoulder, the decreased length could impair its force generation. The 0° and 20° retroversion was the optimum compromise between sufficient TM length and moment arm with minimum impingement.

The posterior medial blind spot of the distal tibia: implications for surgical fixation

The distal tibial blind spot represents an area where improperly measured long screws may pose a risk to surrounding anatomic structures and is not well visualized on AP, mortise, and lateral radiographs. Awareness of this area as well as the use of a 45° external rotation oblique view when placing fixation in this area may prevent iatrogenic injury.

LEVELS OF EVIDENCE

Level V, Expert Opinion.

Deficiencies in pitching biomechanics in baseball players with a history of superior labrum anterior-posterior repair

BACKGROUND

Baseball pitchers who undergo superior labrum anterior-posterior (SLAP) repair often have trouble returning to their previous level of performance. While the reason is often assumed to be diminished shoulder range of motion or other mechanical changes, differences in pitching biomechanics between baseball pitchers with a history of SLAP repair and pitchers with no injury history have not been studied previously.

HYPOTHESIS

The primary hypothesis was that compared with the control group, the SLAP group would exhibit compromised shoulder range of motion (external rotation and horizontal abduction) and internal rotation torque during pitching.

STUDY DESIGN

Controlled laboratory study.

METHODS

Pitching biomechanics were compared retrospectively between a group of 13 collegiate and professional pitchers with a history of a SLAP tear and a control group of 52 pitchers with no history of surgery; groups were matched by age, height, weight, and pitch velocity. Data were collected with an automated 3-dimensional motion analysis system while participants threw fastballs from the windup. Biomechanics of the shoulder (horizontal abduction and external rotation), elbow (flexion, extension velocity, and flexion torque), and body (stride length, shoulder horizontal adduction, and forward trunk tilt) were compared between the 2 groups. For each variable, a Student t test was used at an α level of .05.

RESULTS

Pitchers in the SLAP group exhibited significantly less shoulder horizontal abduction (10.0° ± 13.2° vs 21.0° ± 11.7°, respectively; P = .013) and shoulder external rotation (168.3° ± 12.7° vs 178.3° ± 7.3°, respectively; P = .016) than those in the control group. In addition, players in the SLAP group pitched with a more upright trunk, demonstrated by a less forward trunk tilt at the instant of ball release (30.2° ± 6.3° vs 34.4° ± 6.6°, respectively; P = .048).

CONCLUSION

Pitchers with a history of SLAP repair produce less shoulder horizontal abduction, shoulder external rotation, and forward trunk tilt during pitching than do pitchers with no history of injury.

CLINICAL RELEVANCE

To facilitate normal pitching mechanics, shoulder external rotation and horizontal abduction at 90° should be primary objectives in surgical repair and rehabilitation after SLAP repair. In addition, pitchers should work with their pitching coaches to ensure proper forward trunk tilt.

Contralateral lower trapezius transfer for restoration of shoulder external rotation in traumatic brachial plexus palsy: a preliminary report and literature review

The importance of external rotation of the shoulder is well accepted. Patients with inadequate recovery of shoulder function after nerve transfers for a brachial plexus injury have difficulty in using their reconstructed limb. The options for secondary procedures to improve shoulder function are often limited, especially if the spinal accessory nerve has been used earlier for nerve transfer or as a donor nerve for a free functioning muscle transfer. We have used the contralateral lower trapezius transfer to the infraspinatus in three cases, to restore shoulder external rotation. All patients had significant improvement in shoulder external rotation (mean 97°; range 80°-110°) and improved disability of the arm, shoulder and hand scores. The rotation occurred mainly at the glenohumeral joint, and was independent of the donor side. All patients were greatly satisfied with the outcome. Contralateral lower trapezius transfer appears to help in overall improvement of shoulder function by stabilizing the scapula. The results have remained stable after mean follow-up of 58 months (range 12-86). No donor site deficit was seen in any patient.

Deficits in glenohumeral passive range of motion increase risk of elbow injury in professional baseball pitchers: a prospective study

BACKGROUND

Injuries to the elbow joint in baseball pitchers appear common. There appears to be a correlation between shoulder range of motion and elbow injuries.

PURPOSE

To prospectively determine whether decreased ROM of the throwing shoulder is correlated with the onset of elbow injuries in professional baseball pitchers.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

For 8 consecutive years (2005-2012), passive range of motion of both the throwing and nonthrowing shoulders of all major and minor league pitchers within a single professional baseball organization were measured by using a bubble goniometer during spring training. In total, 505 examinations were conducted on 296 pitchers. Glenohumeral external rotation and internal rotation were assessed in the supine position with the arm at 90° of abduction and in the plane of the scapula. The scapula was stabilized per methods previously established. Total rotation was defined as the sum of external rotation and internal rotation. Passive shoulder flexion was assessed with the subject supine and the scapula stabilized per methods previously established. Elbow injuries and days missed because of elbow injuries were assessed and recorded by the medical staff of the team. Throwing and nonthrowing shoulder measurements were compared by using Student t tests; 1-tailed Fisher exact tests were performed to identify significant associations between shoulder motion and elbow injury. Nominal logistic regression was performed to determine the odds of elbow injury.

RESULTS

Significant differences were noted during side-to-side comparisons within subjects. There were 49 elbow injuries and 8 surgeries in 38 players, accounting for a total of 2551 days missed. Neither glenohumeral internal rotation deficit nor external rotation insufficiency was correlated with elbow injuries. Pitchers with deficits of >5° in total rotation in their throwing shoulders had a 2.6 times greater risk for injury. Pitchers with deficit of ≥5° in flexion of the throwing shoulder had a 2.8 times greater risk for injury.

CONCLUSION

Bilateral differences in shoulder total rotation and flexion had a significant effect on the risk for elbow injuries in pitchers. Clinicians need to be aware of these findings and plan preventive programs that address these issues in hopes of reducing elbow injuries.

Humeral rotational osteotomy for shoulder deformity in obstetric brachial plexus palsy: which direction should I rotate?

Shoulder internal rotation contracture is the most common deformity affecting the shoulder in patients with Obstetric Brachial Plexus Palsy. With progression of the deformity, the glenohumeral joint starts to subluxate and then dislocates. This is accompanied with bony changes of both the humerus and the glenoid. Two opposite direction humeral osteotomies have been proposed for this condition (internal rotation osteotomy (IRO) and external rotation osteotomy (ERO)). This fact of different direction osteotomies has not adequately been explained in the literature. Most orthopedic surgeons may not be able to fully differentiate between these two osteotomies regarding the indications, outcomes and effects on the joint. This review explains these differences in details.

In vivo baseline measurements of hip joint range of motion in suspensory and nonsuspensory anthropoids

Hominoids and atelines are known to use suspensory behaviors and are assumed to possess greater hip joint mobility than nonsuspensory monkeys, particularly for range of abduction. This assumption has greatly influenced how extant and fossil primate hip joint morphology has been interpreted, despite the fact that there are no data available on hip mobility in hominoids or Ateles. This study uses in vivo measurements to test the hypothesis that suspensory anthropoids have significantly greater ranges of hip joint mobility than nonsuspensory anthropoids. Passive hip joint mobility was measured on a large sample of anesthetized captive anthropoids (nonhuman hominids = 43, hylobatids = 6, cercopithecids = 43, Ateles = 6, and Cebus = 6). Angular and linear data were collected using goniometers and tape measures. Range of motion (ROM) data were analyzed for significant differences by locomotor group using ANOVA and phylogenetic regression. The data demonstrate that suspensory anthropoids are capable of significantly greater hip abduction and external rotation. Degree of flexion and internal rotation were not larger in the suspensory primates, indicating that suspension is not associated with a global increase in hip mobility. Future work should consider the role of external rotation in abduction ability, how the physical position of the distal limb segments are influenced by differences in ROM proximally, as well as focus on bony and soft tissue differences that enable or restrict abduction and external rotation at the anthropoid hip joint.

Hip and glenohumeral rotational range of motion in healthy professional baseball pitchers and position players

BACKGROUND

Research suggests that limitations in the hip motion of baseball players may lead to altered motion at the glenohumeral joint to maintain throwing velocity, thereby predisposing the upper extremity to injury.

PURPOSE

To measure and evaluate the correlation between hip and shoulder rotational range of motion (ROM) in healthy professional baseball players.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Ninety-nine professional baseball players (50 pitchers and 49 position players; mean age ± standard deviation [SD], 22 ± 2.8 years; mean height ± SD, 187 ± 5.4 cm; mean weight ± SD, 81.6 ± 7.7 kg) with no history of hip or shoulder injury were tested. Dominant and nondominant hip and glenohumeral joints were measured for the following passive ROM variables: (1) hip internal rotation (IR), (2) hip external rotation (ER), (3) total hip rotational ROM (IR + ER), (4) isolated glenohumeral IR, (5) isolated glenohumeral ER, and (6) total glenohumeral rotational ROM (IR + ER).

RESULTS

Statistically, hip ER and total hip rotational ROM were greater in position players than in pitchers and less in the lead leg compared with the stance leg hip with groups combined; however, differences are not clinically meaningful. Pitchers had more glenohumeral rotational ROM than did position players. For all players, glenohumeral motion had less IR and greater ER in the throwing arm than the nonthrowing arm, but total glenohumeral rotational ROM was equivalent between sides. The correlations between hip and glenohumeral ROM were little, if any, and ranged from r = -0.19 to 0.11 (P = .006-.94) for all players and r = -0.29 to 0.23 (P = .04-.97) for pitchers only.

CONCLUSION

These data suggest no clinically meaningful differences in hip ROM between pitchers and position players and between lead leg and stance legs of all players. There is little or no relationship between hip and glenohumeral ROM in healthy professional baseball players.

CLINICAL RELEVANCE

The study findings add to the growing body of evidence that suggests an absence of chronic hip ROM adaptations. It is therefore suggested that in the hip, unlike the glenohumeral joint, symmetry in ROM between player positions and dominant and nondominant sides should be expected in healthy professional baseball pitchers and position players.

Is protecting the healing ligament beneficial after immobilization in external rotation for an initial shoulder dislocation?

BACKGROUND

Immobilization in external rotation is one of the treatment options for an initial dislocation of the shoulder. However, it remains unclear how long it takes for a Bankart lesion to heal.

HYPOTHESIS

Protection of a healing Bankart lesion from stretching would promote the healing process and decrease the recurrence rate after an initial dislocation of the shoulder.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

This was a multicenter, prospective randomized study. Between January 2005 and August 2009, 109 patients (71 male and 38 female; mean age, 30 years) with an initial traumatic dislocation of the shoulder were enrolled. After 3 weeks of immobilization in external rotation, a shoulder motion restriction band designed to avoid stretching the anteroinferior shoulder capsule was used for 0 weeks (36 patients), 3 weeks (37 patients), or 6 weeks (36 patients). After using the band, patients were allowed to use their shoulders freely, but they were advised to avoid vigorous sport activities for at least 3 months after the injury. Any recurrent dislocation and return to sports were assessed at 2-year follow-up.

RESULTS

Of 109 patients, 90 were followed up for 2 years. The compliance rates were 60% to 72% among the groups (P = .54). The recurrence rate of dislocation was 28% in the 0-week group, 33% in the 3-week group, and 32% in the 6-week group (P = .88) according to the intention-to-treat analysis, and they were a respective 24%, 28%, and 27% according to the per-protocol analysis (P = .95). Based on the sport activity level, the recurrence rates for patients involved in contact sports (7/15, 47%) and those involved in noncontact sports (19/51, 37%) were significantly higher than for those not involved in sport activities (2/24, 8.3%) (P = .0076). Among the 3 groups, there were no significant differences in the recurrence rates. There was no significant difference in the rate of return to sports (P = .39).

CONCLUSION

No difference in the recurrence rate was seen with the use of a shoulder motion restriction band after 3 weeks of immobilization in external rotation after an initial dislocation of the shoulder.