Biomechanics of the elbow in sports

Medical advisability of softball youth pitching recommendations on the internet

OBJECTIVE

Developing softball pitchers are prone to injury due to the repetitive throwing motion. Many children and parents use the internet as a source of medical advice, but this information may not always be aligned with medical guidelines. The purpose of this study was to assess the medical advisability of injury prevention guidelines for developing softball pitchers on websites using Google as the primary search engine.

METHODS

The first 100 websites populated from a Google search using the term softball youth pitching recommendations were evaluated. Each website was categorized as discussing baseball, softball, or both, and as athletic, commercial, or educational. For every website, 16 recommendations described by the American Orthopaedic Society for Sports Medicine (AOSSM) Stop Sports Injuries softball injury prevention guidelines (Table 1) were scored as in agreement (+1), different guideline mentioned (0.5), no mention (0), or discordant (-1).[Table: see text].

RESULTS

Of the 98 qualifying websites, 57 advised only about softball, while 19 advised about both baseball and softball. Fifty websites had no mention of any recommendation outlined by AOSSM. Websites that were mostly in agreement with AOSSM were educational websites (mean score = 3.9, p = 0.02), websites discussing only softball (mean score = 2.0, p = 0.02), and the first 50 websites (mean score = 2.2, p = 0.04). The most common discordant guideline was differing opinions in pitch count (13 websites).

CONCLUSION

The most common category in disagreement with AOSSM was different pitch count guidelines, highlighting a need for websites to provide more consistent information using high-quality resources. Educational websites, websites discussing only softball, and the first 50 websites had the highest scores, indicating that these types of websites are most likely to have the highest amount of medically advisable information. We recommend users conduct targeted Google searches on reliable websites for information on pitching softball recommendations to maximize the validity of Google search results.

Estimation of joint torque in dynamic activities using wearable A-mode ultrasound

The human body constantly experiences mechanical loading. However, quantifying internal loads within the musculoskeletal system remains challenging, especially during unconstrained dynamic activities. Conventional measures are constrained to laboratory settings, and existing wearable approaches lack muscle specificity or validation during dynamic movement. Here, we present a strategy for estimating corresponding joint torque from muscles with different architectures during various dynamic activities using wearable A-mode ultrasound. We first introduce a method to track changes in muscle thickness using single-element ultrasonic transducers. We then estimate elbow and knee torque with errors less than 7.6% and coefficients of determination (R2) greater than 0.92 during controlled isokinetic contractions. Finally, we demonstrate wearable joint torque estimation during dynamic real-world tasks, including weightlifting, cycling, and both treadmill and outdoor locomotion. The capability to assess joint torque during unconstrained real-world activities can provide new insights into muscle function and movement biomechanics, with potential applications in injury prevention and rehabilitation.

Biomechanical Characteristics of Ulnar Collateral Ligament Injuries Treated With and Without Augmentation: A Network Meta-analysis of Controlled Laboratory Studies

BACKGROUND

Treatment of ulnar collateral ligament (UCL) tears with suture tape augmentation has gained interest given preliminary reports of favorable biomechanical characteristics. No study to date has quantitatively assessed the biomechanical effects of multiple augmentation techniques relative to the native UCL.

PURPOSE

To perform a systematic review and meta-analysis of controlled laboratory studies to assess and comparatively rank biomechanical effects of UCL repair or reconstruction with or without augmentation.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

PubMed, OVID/Medline, and Cochrane databases were queried in January 2023. A frequentist network meta-analytic approach was used to perform mixed-treatment comparisons of UCL repair and reconstruction techniques with and without augmentation, with the native UCL as the reference condition. Pooled treatment estimates were quantified under the random-effects assumption. Competing treatments were ranked in the network meta-analysis by using point estimates and standard errors to calculate P scores (greater P score indicates superiority of treatment for given outcome).

RESULTS

Ten studies involving 206 elbow specimens in which a distal UCL tear was simulated were included. UCL reconstruction with suture tape augmentation (AugRecon) restored load to failure to a statistically noninferior magnitude (mean difference [MD], -1.99 N·m; 95% CI, -10.2 to 6.2 N·m; P = .63) compared with the native UCL. UCL reconstruction (Recon) (MD, -12.7 N·m; P < .001) and UCL repair with suture tape augmentation (AugRepair) (MD, -14.8 N·m; P < .001) were both statistically inferior to the native UCL. The AugRecon condition conferred greater load to failure compared with Recon (P < .001) and AugRepair (P = .002) conditions. AugRecon conferred greater torsional stiffness relative to all other conditions and was not statistically different from the native UCL (MD, 0.32 N·m/deg; 95% CI, -0.30 to 0.95 N·m/deg; P = .31). Medial ulnohumeral gapping was not statistically different for the AugRepair (MD, 0.30 mm; 95% CI, -1.22 to 1.82 mm; P = .70), AugRecon (MD, 0.57 mm; 95% CI, -0.70 to 1.84 mm; P = .38), or Recon (MD, 1.02 mm; 95% CI, -0.02 to 2.05 mm; P = .055) conditions compared with the native UCL. P-score analysis indicated that AugRecon was the most effective treatment for increasing ultimate load to failure and torsional stiffness, whereas AugRepair was the most effective for minimizing medial gapping.

CONCLUSION

AugRecon restored load to failure and torsional stiffness most similar to the parameters of the native UCL, whereas Recon and AugRepair did not restore the same advantageous properties at time zero. Medial ulnohumeral gapping during a valgus load was minimized by all 3 treatments. Based on network interactions, AugRecon was the superior treatment approach for restoring important biomechanical features of the UCL at time zero that are jeopardized during a complete distal tear.

Ulnar Collateral Ligament Repair With Suture Tape Augmentation: Can You Overtighten?

BACKGROUND

There has been a renewed interest and, recently, wider implementation of ulnar collateral ligament (UCL) repair in throwing athletes because of improvement in ligament repair technology and corresponding outcome data.

PURPOSE

To compare the biomechanical parameters and failure mode between 2 brace-tightening techniques for UCL repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eleven matched pairs of cadaveric arms were procured. One limb from each pair underwent UCL repair with suture tape augmentation with either (1) attempted restoration of physiologic ligament tension or (2) maximal tension. Each specimen was subjected to 10 cycles of subfailure valgus torque at 90º of flexion in the intact state after UCL avulsion and then after UCL repair. Specimens were then torqued to failure. Articular contact mechanics, linear gap distance, angular displacement, failure torque, failure stiffness, and suture tape pull-through length were recorded. Two-way analysis of variance and paired t tests were used to test for statistical differences.

RESULTS

There was a significant effect (P = .01) of tightening on joint contact area. There was a significant decrease in gap distance (P = .03) and angular displacement (P = .004) from the torn condition to the repaired condition for the maximum tension group, without a significant difference in gap distance from the intact condition. Failure torque and stiffness were not significantly different between groups, although there was a significant difference (P = .001) in the overall suture tape pull-through length.

CONCLUSION

Although there are potential physiologic changes at time zero-including significant decreases in contact area, normalized gap distance, and normalized angular displacement with maximal tension repair-examination of failure biomechanics suggests that these effects may be mitigated over time within the construct by suture tape pull-through at the tape-anchor interface. Neither method of UCL repair with suture tape augmentation resulted in overconstraint of the elbow joint compared with the native ligament biomechanics.

CLINICAL RELEVANCE

As more long-term outcome data from UCL repair with suture tape augmentation emerge, there will be wider implementation with various techniques to tension the suture tape. Examining the potential biomechanical sequelae of the UCL repair construct applied under maximal tension will help further refine recommendations for surgeons who utilize this technique for UCL repair.

Return to Sport After Nonoperative Management of Elbow Ulnar Collateral Ligament Injuries: A Systematic Review and Meta-analysis

BACKGROUND

Elbow ulnar collateral ligament (UCL) injuries can result in significant functional impairment in throwing and overhead athletes. UCL reconstruction and repair are proven treatments to restore stability, but the efficacy of nonoperative management is unclear.

PURPOSE

To determine the rate of return to sports (RTS) and return to previous level of play (RTLP) in athletes sustaining medial elbow ulnar collateral ligament (UCL) injuries treated nonoperatively.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A literature search was performed using Scopus, PubMed, Medline, the Cochrane Database for Systematic Review, and the Cochrane Central Register for Controlled Trials according to the 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Inclusion criteria were limited to level 1 to 4 human studies reporting on RTS outcomes after nonoperative management of UCL injuries.

RESULTS

A total of 15 studies, consisting of 365 patients with a mean age of 20.45 ± 3.26 years, were identified. Treatment primarily consisted of platelet-rich plasma (PRP) injections with physical therapy (n = 189 patients; n = 7 studies) versus physical therapy alone (n = 176 patients; n = 8 studies). The overall RTS rate was 79.7% and the overall RTLP rate was 77.9%. Increasing UCL injury severity grade was associated with lower RTS rates. The RTS rate for proximal tears (89.7%; n = 61/68) was significantly greater than that for distal tears (41.2%; n = 14/34) (P < .0001). No significant difference in RTS rate was seen in patients treated with PRP versus those who did not receive PRP (P = .757).

CONCLUSION

For athletes undergoing nonoperative management of UCL injuries, the overall RTS and RTLP rates were 79.7% and 77.9%, respectively, with excellent outcomes in grade 1 and grade 2 UCL injuries, specifically. The RTS rate for proximal tears was significantly higher than that for distal tears. Athletes were most commonly treated with PRP injection and physical therapy.

Factors Important to Patient Decision-Making After Ulnar Collateral Ligament Injury in Competitive High School and Collegiate Baseball Players

Background

Patients are faced with several treatment decisions after an ulnar collateral ligament (UCL) injury: nonoperative versus operative treatment, repair versus reconstruction, and immediate versus delayed surgery.

Purpose/Hypothesis

The aim of this study was to investigate the factors important to patients when deciding which treatment to pursue after a UCL injury. We hypothesized that (1) length of time away from sports and seasonal timing would be important to patients and (2) treatment decision-making would be heavily influenced by how many and which seasons of their baseball career would be missed.

Study Design

Cross-sectional study.

Methods

High school and collegiate baseball players with UCL tears treated at an academic institution were surveyed retrospectively on their sports participation at the time of injury and their UCL injury treatment decisions. Respondents rated the influence of various factors on a 5-point Likert scale, and they selected the top 3 factors and the single most important factor influencing their treatment decisions. Multiple logistic regression analysis was used to assess the relationship between player characteristics and factors important to their treatment decision.

Results

A total of 83 athletes completed the survey; 40 were in high school and 43 were in college at the time of injury; 7 were treated nonoperatively and 76 underwent surgery (66 immediately and 10 in a delayed fashion), 10 with UCL repair and 66 with UCL reconstruction. The ability to play competitive baseball in the long term was very important or extremely important to 90% of players, while the ability to play in the short term was very important or extremely important to 17%. Length of recovery and seasonal timing were also important factors for 53% and 54% of players, respectively, and almost all (90%) highly valued advice from a surgeon. Possible failure of nonoperative treatment leading to increased time away and the possible loss of 2 consecutive baseball seasons heavily influenced decision-making in 41% of respondents.

Conclusion

Survey respondents were driven by the desire to play baseball in the long term. Treatment decisions were influenced by the length of recovery and by the seasonal timing of their injury, both of which affect how many and which seasons of baseball a player may miss. Patients found advice from their surgeon to be extremely important to decision-making.

Outcomes following arthroscopic posteromedial osteophyte resection and risk of future ulnar collateral ligament reconstruction

BACKGROUND AND HYPOTHESIS

Despite successful return-to-sport (RTS) outcomes after posteromedial osteophyte resection, one possible consequence of osteophyte removal is increased stress on the ulnar collateral ligament (UCL), leading to a UCL injury. It is currently unknown how often overhead athletes who undergo isolated posteromedial osteophyte resection subsequently require UCL reconstruction (UCLR). Therefore, the purpose of this study was to report outcomes following arthroscopic resection of posteromedial osteophytes in overhead athletes and determine whether overhead athletes who underwent arthroscopic posteromedial osteophyte resection for posteromedial impingement went on to require UCL surgery. We hypothesized that there would be a high rate of RTS following osteophyte resection and that players who underwent arthroscopic posteromedial osteophyte resection would have a >10% risk of requiring subsequent UCLR or UCL repair.

MATERIALS AND METHODS

All patients who underwent elbow arthroscopy from 2010-2020 at a single institution were reviewed. Patients were included if they underwent isolated arthroscopic posteromedial osteophyte resection without concomitant UCL surgery, were overhead athletes at the onset of posteromedial impingement symptoms, and had no history of elbow surgery. Primary outcomes included RTS rate, complications, and subsequent shoulder and/or elbow injury and surgery, as well as several patient-reported outcome measures (Kerlan-Jobe Orthopaedic Clinic score, Timmerman-Andrews elbow score, and Conway-Jobe score).

RESULTS

Overall, 36 overhead athletes were evaluated at 5.1 ± 3.4 years postoperatively, including 28 baseball pitchers, 3 baseball catchers, 3 softball players, 1 tennis player, and 1 volleyball player. Of the overhead athletes, 77% were able to RTS; the mean Kerlan-Jobe Orthopaedic Clinic and satisfaction scores were 70 and 75, respectively; and 89% of athletes had either excellent (73%) or good (16%) Conway-Jobe scores at long-term follow-up. Subsequent UCLR was required in 18% of baseball pitchers (n = 5) at a median of 13 months postoperatively. Of the 5 UCLRs, 3 were performed shortly after posteromedial osteophyte resection (6, 7, and 13 months postoperatively) whereas the other 2 were performed at 6.2 and 7.5 years postoperatively.

CONCLUSION

Following arthroscopic posteromedial osteophyte resection, 77% of athletes were able to RTS. Baseball pitchers who undergo arthroscopic resection of posteromedial osteophytes for posteromedial impingement have an 18% risk of subsequent UCLR.

Performance-environment mutual flow model using big data on baseball pitchers

Introduction

The study investigated the baseball pitching performance in terms of release speed, spin rate, and 3D coordinate data of the release point depending on the ball and strike counts.

Methods

We used open data provided on the official website of Major League Baseball (MLB), which included data related to 580 pitchers who pitched in the MLB between 2015 and 2019.

Results

The results show that a higher ball count corresponds to a slower release speed and decreased spin rate, and a higher strike count corresponds to a faster release speed and increased spin rate. For a higher ball count, the pitcher's release point tended to be lower and more forward, while for a higher strike count, the pitcher's release point tended to be to the left from the right pitcher's point of view. This result was more pronounced in 4-seam pitches, which consisted the largest number of pitchers. The same tendency was confirmed in other pitches such as sinker, slider, cut ball, and curve.

Discussion

Our findings suggest that the ball count is associated with the pitcher's release speed, spin rate, and 3D coordinate data. From a different perspective, as the pitcher's pitching performance is associated with the ball and strike count, the ball and strike count is associated with pitching performance. With regard to the aforementioned factor, we propose a “performance-environment flow model,” indicating that a player's performance changes according to the game situation, and the game situation consequently changes the player's next performance.

Change in humeral anchor position significantly affects isometry in ulnar collateral ligament repair: a 3-dimensional computer modeling study

BACKGROUND

Medial ulnar collateral ligament (UCL) repair utilization is increasing in recent years, bolstered by shorter rehabilitation and satisfactory clinical outcomes. Although previous literature has illustrated the importance of tunnel position on restoring graft isometry in reconstruction, there remains a paucity of literature guiding anchor placement in UCL repair. The purpose of this study is to design a 3-dimensional (3D) elbow model to understand the effect of anchor location on UCL repair isometry.

METHODS

A 3D computer model of an elbow joint was created using computed tomographic and magnetic resonance imaging MRI scans from a single patient. The humeral and ulnar attachments of the UCL were plotted using 3 methodologies: (1) geometric cloud mapping and (2) quantitative measurements from the anatomic studies by Camp et al and (3) Frangiamore et al. A 3.5-mm-diameter clockface was placed on each attachment site, which allowed for simulation of 12 distinct 1.75-mm deviations in anchor position. The 3 models were ranged through 0°-120° at 10° increments, and the 3D distances were measured between the ligament centroids. The humeral and ulnar anchors were sequentially repositioned around the clockfaces, and construct lengths were again measured to evaluate changes in isometry. A paired Student t test was performed to determine if there was a significant difference in isometry between the humeral and ulnar anchor deviations.

RESULTS

Using method 1, the UCL repair length at 90° of elbow flexion was 26.8 mm. This construct underwent 13.6 mm of total excursion for a 46.4% change in length throughout its arc of motion. Method 2 produced a 19.3-mm construct that underwent 0.8 mm of excursion for a 3.9% length change throughout the arc. Method 3 produced a 24.5-mm construct that underwent 2.3 mm of excursion for a 9.4% length change. Identifying ligament footprints using the quantitative anatomic measurements from Camp et al and Frangiamore et al improved construct isometry through 120° of flexion (length changes of 3.9% and 9.4%, respectively) when compared to using the geometric cloud technique alone (46.4% length change). Humeral anchor deviations produced a significant increase in repair construct excursion compared with ulnar anchor deviations (P < .001).

CONCLUSION

When performing UCL repair, small deviations in humeral anchor position may significantly influence ligament repair isometry. Using quantitative anatomic data may help identify anchor positions with improved repair isometry. Particularly when addressing detachments of the humeral footprint, surgeons should be critical of the humeral anchor position in order to restore native anatomy and optimal biomechanics.

Upper Body Injuries in Golfers

PURPOSE OF REVIEW

Golf is a sport that can be played by an athlete of any age, which enhances its popularity. Each golfer's swing is unique, and there is no "right" way to swing the golf club; however, the professional golfer often has more of a consistent swing as opposed to an amateur golfer. A collaborative, team approach involving the golfer with a swing coach, physical therapist, and physician often can be informative on how to prevent golf injury, but also how to treat golf injury if it occurs.

RECENT FINDINGS

As a rotational sport, the golfer needs to be trained and treated with respect for how the body works as a linkage system or kinetic chain. A warm-up is recommended for every golfer before practicing or playing, and this warm-up should account for every segment of the linkage system. Though it has been thought of as a relatively safe sport, injuries can be seen with golfers of any age or skill level, and upper body injuries involving the cervical and thoracic spine, shoulder, elbow, and wrist are common. A narrative review is provided here of the epidemiology of golf injury and common injuries involving each of these upper body regions. In addition, treatment and injury prevention recommendations are discussed.

Decreased Trunk Rotation at Foot Contact in Professional Baseball Pitchers With Prior Conservatively Managed SLAP Tears: A Propensity Score-Matched Analysis

PURPOSE

To compare kinematic and kinetic parameters between a cohort of fully recovered professional pitchers with prior shoulder injury treated conservatively and a cohort with no prior shoulder injury.

METHODS

Twenty-six fully recovered professional baseball pitchers with a history of shoulder injury treated conservatively pitched 8 to 10 fastball pitches using 3-dimensional motion capture (480 Hz). All shoulder injuries occurred within a 1- to 4-year time span from biomechanical evaluation and were severe enough to prevent pitchers from playing for between 1 and 12 months. These pitchers were propensity score matched by age, height, weight, handedness, and ball velocity to pitchers with no prior injury history (control) at a ratio of 1:4. We compared 21 kinematic and 11 kinetic parameters between groups using appropriate parametric testing. Subanalysis comparisons of pitchers with prior SLAP injury as well as rotator cuff tendinitis were also performed.

RESULTS

SLAP tears (n = 11, 42.3%) were the most frequently reported injury, followed by rotator cuff tendinitis and/or shoulder impingement (n = 7, 26.9%). Compared with the control group, the 26 pitchers with prior injury showed no significant differences across the kinematic and kinetic factors. However, the SLAP tear subgroup did show significantly less trunk rotation at foot contact compared with controls (34.1° ± 4.9° vs 39.2° ± 10.2°, P = .0075).

CONCLUSIONS

Fully recovered professional baseball pitchers with shoulder injuries treated conservatively showed no significant differences in kinetics or kinematics compared with their propensity score-matched counterparts, suggesting that shoulder injury alone may not greatly alter pitching mechanics. However, whereas prior groups have shown a decrease in trunk rotation at foot contact after surgical repair for SLAP tears, our study suggests that this kinematic change may alternatively originate with the injury itself.

CLINICAL RELEVANCE

Understanding the cause of biomechanical adaptations by pitchers after injury can better aid clinicians and coaching staff in providing individualized and specific care to the throwing athlete.

Ulnar collateral ligament reconstruction in javelin throwers: an analysis of return to play rates and patient outcomes

BACKGROUND

Although results after ulnar collateral ligament reconstruction (UCLR) in baseball players have been well documented, the literature is replete regarding the outcomes after UCLR in javelin throwers.

PURPOSE

To report outcomes after UCLR in javelin throwers.

HYPOTHESIS

UCLR in javelin throwers will result in a high rate of return to play similar to that of previously published studies from athletes of other sports.

METHODS

All patients who were identified preoperatively as javelin throwers and underwent UCLR between 2011 and 2017 with a minimum 2-year follow-up were eligible for inclusion. Patients were assessed with the Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow score, Timmerman-Andrews Elbow score, Conway-Jobe score, patient satisfaction, return to sport rate questionnaire, and the occurrence of any postoperative complications.

RESULTS

Eighteen patients met the inclusion criteria. Complete follow-up was available in 16 (88.9%) patients. The average age at surgery was 21.2 ± 2.0 (range, 18.6-24.9) years. At the final follow-up, the average Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow score and Timmerman-Andrews Elbow score were 77.3 (range, 18.7-98.4) and 91.8 (range, 70.0-100.0), respectively. Outcomes on the Conway-Jobe scale were as follows: excellent (n = 6; 37.5%), good (n = 4; 25%), fair (n = 6; 37.5%). Ten (62.5%) patients returned to play at an average of 12.2 ± 3.6 (range, 6.0-18.0) months after surgery. Two (12.5%) patients sustained a shoulder injury postoperatively; however, neither required surgery.

CONCLUSION

UCLR in javelin throwers results in good outcomes with a low rate of reinjury/reoperation. However, the return to play rate (62.5%) and good/excellent outcomes per the Conway-Jobe scale (68.8%) are lower than what has been previously reported in baseball players and javelin throwers. Further investigation regarding outcomes in javelin throwers after UCLR is warranted.

Shoulder External Rotational Properties During Physical Examination Are Associated With Injury That Requires Surgery and Shoulder Joint Loading During Baseball Pitching

BACKGROUND

Throwing arm injuries are common because of the demand on the shoulder. The shoulder is qualitatively checked regularly by team physicians. Excessive instability and joint loading in baseball pitching are risk factors for throwing arm injuries. Knowledge of shoulder flexibility, range of motion, and joint loading may provide new insights for treatments to reduce the likelihood of injury incidence.

PURPOSE

To investigate the relationship among injuries, shoulder external rotational properties, and shoulder joint loading in baseball pitchers.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Pitching kinetics, shoulder rotational tests, and self-reported injury questionnaires were used to study 177 collegiate baseball pitchers. Pitching motion data were collected at 240 Hz using a motion capture system. A custom program calculated the shoulder joint loading. The shoulder rotational test quantitatively records shoulder range of motion and flexibility using a custom-made wireless device. Self-reported injury questionnaires were filled out during tests and yearly follow-ups. The total length of the study was 5 years. Analysis of variance, chi-square, and regression tests were performed to compare differences among groups and detect correlations with surgery and shoulder joint loadings.

RESULTS

There were significant differences in shoulder flexibility among surgery groups. Shoulder external rotational properties during physical examination were significantly associated with shoulder joint loading in baseball pitching. High shoulder external rotation was associated with 14% to 36% lower shoulder posterior force and adduction, internal rotation, and horizontal adduction torque (P < .05). High shoulder flexibility was associated with 13% higher anterior force (P < .05). High shoulder external rotation before external rotation torque was applied was associated with 13% to 33% lower shoulder inferior force and adduction, internal rotation, and horizontal adduction torque (P < .05). There were no significant differences in shoulder joint loading among the surgery groups.

CONCLUSION

Shoulder injuries that require surgery were associated with shoulder external rotation flexibility. High shoulder external rotation may be advantageous because it lowers the force and torque on the shoulder joint.

CLINICAL RELEVANCE

The ability to understand shoulder external rotational properties, joint loading, and injury during baseball pitching helps further our understanding of injury mechanisms. The shoulder rotational test should be used as a screening tool to identify players at risk.

Lateral epicondylosis: A literature review to link pathology and tendon function to tissue-level treatment and ergonomic interventions

BACKGROUND

Common treatments for lateral epicondylosis (LE) focus on tissue healing. Ergonomic advice is suggested broadly, but recommendations based on biomechanical motion parameters associated with functional activities are rarely made. This review analyzes the role of body functions and activities in LE and integrates the findings to suggest motion parameters applicable to education and interventions relevant to activities and life roles for patients.

PURPOSE

This study examines LE pathology, tendon and muscle biomechanics, and population exposure outlining potentially hazardous activities and integrates those to provide motion parameters for ergonomic interventions to treat or prevent LE. A disease model is discussed to align treatment approaches to the stage of LE tendinopathy.

STUDY DESIGN

Integrative review METHODS: We conducted in-depth searches using PubMed, Medline, and government websites. All levels of evidence were included, and the framework for behavioral research from the National Institutes of Health was used to synthesize ergonomic research.

RESULTS

The review broadened the diagnosis of LE from a tendon ailment to one affecting the enthesis of the capitellum. It reinforced the continuum of severity to encompass degeneration as well as regeneration. Systematic reviews confirmed the availability of evidence for tissue-based treatments, but evidence of well-defined harm reducing occupational interventions was scattered amongst evidence levels. Integration of biomechanical studies and population information gave insight into types of potentially hazardous activities and provided a theoretical basis for limiting hazardous exposures to wrist extensor tendons by reducing force, compression, and shearing during functional activities.

CONCLUSIONS

These findings may broaden the first treatment approach from a passive, watchful waiting into an active exploration and reduction of at-risk activities and motions. Including the findings into education modules may provide patients with the knowledge to lastingly reduce potentially hazardous motions during their daily activities, and researchers to define parameters of ergonomic interventions.

Overuse-related instability of the elbow: the role of CT-arthrography

The elbow is a complex joint whose biomechanical function is granted by the interplay and synergy of various anatomical structures. Articular stability is achieved by both static and dynamic constraints, which consist of osseous as well as soft-tissue components. Injuries determining instability frequently involve several of these structures. Therefore, accurate knowledge of regional anatomy and imaging findings is fundamental for a precise diagnosis and an appropriate clinical management of elbow instability. This review focuses particularly on the varied appearance of overuse-related elbow injuries at CT-arthrography.

Return to Performance After Ulnar Collateral Ligament Reconstruction in Major League Baseball Pitchers: A Case-Control Assessment of Advanced Analytics, Velocity, Spin Rates, and Pitch Movement

Background:

There are limited data on the performance or pitching metrics of Major League Baseball (MLB) pitchers who returned to play after ulnar collateral ligament reconstruction (UCLR).

Purpose:

To describe MLB pitcher performance after return from primary UCLR, compare the velocity and pitch characteristics against the preoperative season, and determine if performance analytics can predict successful return to pitching after UCLR.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

This study included 63 pitchers who underwent primary UCLR between 2015 and 2019. Publicly available advanced analytics and pitch metrics from the first 2 postoperative seasons were compared with the preoperative (index) season as well as with an uninjured control group.

Results:

Overall, 57% of the pitchers successfully returned to the MLB level. Although they threw significantly fewer pitches (P = .012) and innings (P = .022) in postoperative year 1 as compared with the index season, there were no significant differences in pitch velocity, release extension, perceived velocity, or performance as measured by advanced analytics. Also, as compared with the index season, returners demonstrated increased postoperative spin rates on curveballs (P = .001) and sliders (P = .010), and curveball horizontal movement was significantly increased (P = .007); however, horizontal movement was significantly decreased for 4-seam fastballs (P = .026), changeups (P = .005), and sinkers (P = .019). The vertical movement on 4-seam fastballs was greater (P < .001) in postoperative year 1, and the vertical movement on curveballs (P = .031) and sinkers (P = .010) was greater in postoperative year 2 when compared with the index season. Pitchers who failed to return to the MLB level had a lower preoperative strikeout percentage (P = .047), fewer strikeouts per 9 innings pitched (P = .046), fewer wins above replacement ([WAR]; P = .026), and lower player value (P = .030) than the pitchers who returned.

Conclusion:

Pitchers returning to the MLB level after UCLR demonstrated changes in pitch movement profiles and spin rates postoperatively, but there were no differences in velocity or many advanced analytics upon return. Pitchers with lower strikeout metrics, fewer WAR, and less player value before surgery may have an elevated risk of failing to return to the MLB level.

Medial Ulnar Collateral Ligament Repair With Internal Brace Augmentation: Results in 40 Consecutive Patients

Background:

Medial ulnar collateral ligament (MUCL) repair has been proven to be effective in nonprofessional overhead-throwing athletes, with faster and higher rates of return to play (RTP) than the more traditional Tommy John reconstruction. Biomechanical studies and clinical data suggest that MUCL repair augmented with a collagen-coated internal brace may be an effective treatment option in this patient population.

Purpose:

To evaluate the functional outcomes of young nonprofessional athletes who underwent MUCL repair with internal brace augmentation for medial elbow instability. The hypothesis was that these patients will have high rates of RTP and improved functional outcomes.

Study Design:

Case series; Level of evidence, 4.

Methods:

Nonprofessional overhead athletes treated with MUCL repair with internal brace augmentation between 2015 and 2017 were prospectively evaluated for a minimum of 1 year. Preoperatively, all patients had evidence of medial elbow pain caused by MUCL insufficiency, as confirmed by signal changes on magnetic resonance imaging and valgus instability on arthroscopic examination. These findings did not allow them to participate in their chosen sport or profession, and each patient had failed nonoperative treatment. Postoperative outcomes were evaluated using the Overhead Athlete Shoulder and Elbow Score of the Kerlan-Jobe Orthopaedic Clinic. Complications were recorded and detailed.

Results:

A total of 40 nonprofessional overhead athletes were included in this study (35 men and 5 women; mean age, 17.8 years [range, 14-28 years]). The mean follow-up time was 23.8 months (range, 12-44 months). The mean postoperative Kerlan-Jobe Orthopaedic Clinic score was 92.6 (range, 64-100). Overall, 37 athletes (92.5%) returned to play or profession at the same level or higher at a mean time of 6.9 months (range, 2-12 months). Three patients did not RTP: 1 was limited by a concomitant medical diagnosis, and the other 2 chose not to resume athletics after the procedure but remained symptom free.

Conclusion:

In the nonprofessional athlete, primary MUCL repair with internal brace augmentation is a viable alternative to traditional repair techniques or reconstruction, allowing for a rapid RTP and promising functional outcomes.

Evaluation and management of elbow injuries in the adolescent overhead athlete

With an increased interest in youth sports, the burden of overhead throwing elbow injuries accompanying early single-sport focus has steadily risen. During the overhead throwing motion, valgus torque can reach and surpass Newton meters (N m) during the late cocking and early acceleration phases, which exceeds the tensile strength (22.7–33 N m) of the ulnar collateral ligament. While the ulnar collateral ligament serves as the primary valgus stabilizer between and degrees of elbow flexion, other structures about the elbow must contribute to stability during throwing. Depending on an athlete’s stage of skeletal maturity, certain patterns of injury are observed with mechanical failures resulting from increased medial laxity, lateral-sided compression, and posterior extension shearing forces. Together, these injury patterns represent a wide range of conditions that arise from valgus extension overload. The purpose of this article is to review common pathologies observed in the adolescent overhead throwing athlete in the context of functional anatomy, osseous development, and throwing mechanics. Operative and non-operative management and their associated outcomes will be discussed for these injuries.

Increase in Use of Medial Ulnar Collateral Ligament Repair of the Elbow: A Large Database Analysis

Purpose

To assess the current national rate of medial ulnar collateral ligament (MUCL) repair of the elbow and delineate the patient demographics of those undergoing repair.

Methods

A retrospective review and analysis of a national private insurance database was conducted covering 2007-2017 using Pearl Diver technologies. All patients diagnosed with a MUCL injury and those who underwent repair were included using Clinical Modification and Current Procedural Terminology code 24345, referencing repair of the ulnar collateral ligament of the elbow with local tissue. The extracted data included patient age at time of procedure, sex, race, region, year of surgery, insurance type, hospital setting, and any associated diagnoses with 90 days of the repair procedure. Standard descriptive methods characterized our study sample to calculate frequency counts and percentages. Means with respective standard deviations and/or standard errors, and 95% confidence intervals were calculated and reported for continuous variables, whereas frequencies and percentages were reported for categorical variables. Pearson χ² tests were used to determine differences between group proportion categorical variables. Significance was considered at a P ≤ .05.

Results

From 2007 to 2014, MUCL injuries showed an upward trend in incidence per 100,000 from 4.59 to 7.19 (56% increase) within the database population. Accordingly, the incidence of MUCL repair rose from 0.016 to 0.49 (2962%). However, from 2015-2017 there was a drop in both categories, as injury incidence fell from 7.19 to 1.48 whereas repair rates dropped from 0.49 to 0.012. The ages undergoing repair show a significant peak in 15-24-year-olds. The incidence of MUCL repair was greatest in the West and South (P < .01). Male patients had a greater incidence of MUCL injury, and a greater incidence of MUCL repair per 100,000 persons compared to females (P < .01).

Conclusions

MUCL repair has emerged as a viable alternative to reconstruction in select indications. The impetus for this change may be to provide a quicker return to sport and fewer complications, largely due to recent improvements in surgical technique for MUCL repair. As anticipated, the incidence of MUCL repair had steadily increased in the United States from 2007 to 2014, with a subsequent relatively inexplicable decrease primarily in 2017, according to the database utilized in this study. The 15-24 year-old age group encompassing young athletes has the greatest incidence of repair by a significant margin.

Level of Evidence

IV, Therapeutic Case Series.

Forearm flexor injury is associated with medial ulnar collateral ligament injury in throwing athletes

BACKGROUND

Elbow ulnar collateral ligament (UCL) injuries have become increasingly common in throwing athletes. The forearm flexors (FF) have been studied as biomechanical stabilizers for the medial elbow. However, there are no studies investigating the association of concomitant UCL injuries and FF injuries in throwing athletes.

OBJECTIVE

To determine if throwing athletes with a complete UCL injury had a greater likelihood of concomitant FF injury than those with a partial UCL injury.

DESIGN

Descriptive retrospective epidemiological study.

SETTING

Academic, tertiary care medical center.

PATIENTS

Throwing related UCL injuries in patients aged 12-24 years.

INTERVENTIONS/METHODS

Electronic medical records and key word searches identified all patients from January 1, 2010 to December 31, 2019. A board certified and fellowship trained musculoskeletal radiologist reviewed all advanced imaging studies.

RESULTS

Fifty-four patients (46 male, 8 female, mean age 17.1 years, SD 2.3) were included. Fifty-four UCL injuries (21 complete ruptures, 16 proximal partial injuries, 17 distal partial injuries) were confirmed by magnetic resonance imaging (MRI). Twenty-eight FF injuries (22 strains, 6 tears) were diagnosed with MRI and/or MRI-arthrogram. There was a significant association between sustaining a FF injury and UCL reconstruction (UCL-R) (X² = [1, N = 54], = 3.97, P = .046) (15/22, 68.2%), as well as FF injury and UCL injury location (X² = [1, N = 33], = 3.86, P = .049) (10/17, distal partial UCL injury, 58.8%). Analysis of FF injury and complete UCL tear is not significant (X² = [1, N = 54], = 3.02, P = .08) (14/21, 66.7%).

CONCLUSIONS

The data indicate that FF injury is associated with UCL injury in throwing athletes. Future prospective studies should investigate causation versus correlation of FF and UCL injury in throwing athletes. The results of this study have applications to multiple sports medicine areas that include but are not limited to surgical, nonsurgical, prehabilitation, rehabilitation, and sports performance. This study reveals a strongly significant association between FF injury and concomitant UCL injury in throwing athletes.

THE NONOPERATIVE REHABILITATION OF A TRAUMATIC COMPLETE ULNAR COLLATERAL LIGAMENT TEAR OF THE ELBOW IN A HIGH SCHOOL WRESTLER: A CASE REPORT

Background and Purpose

Injuries frequently occur in competitive wrestling, with the elbow joint representing about 25% of all injuries. Specific to the elbow, the ulnar collateral ligament (UCL) can be injured traumatically from takedowns in wrestling. In athletes with complete UCL tears, surgical management is often recommended with nonoperative management resulting in less favorable outcomes. The purpose of this case report is to present a nonoperative criterion-based rehabilitation program for a high school wrestler with a complete UCL tear of the elbow.

Case Description

A 17-year-old male wrestler presented to outpatient physical therapy with a complete UCL tear sustained from falling on an outstretched hand during a wrestling match. He presented with limited elbow range of motion (ROM), medial elbow instability, and weakness of the involved shoulder and forearm musculature. A three staged criterion-based rehabilitation protocol was developed for this subject based on specific criteria, including pain, elbow ROM, arm strength, and functional outcomes.

Outcomes

The subject was treated for nine visits over six weeks, and demonstrated improvements in all strength tests of the involved upper extremity, with elbow flexion strength improving the most by 58%. Return to sport (RTS) tests were used to assess the subject's ability to return to practice. At approximately eight weeks after initial injury, the subject was able to return to full participation in competitive wrestling with no reports of elbow pain or instability.

Discussion

Through the utilization of a criterion-based rehabilitation protocol for the nonoperative management of an UCL injury, this high school wrestler was able to safely progress back to wrestling without pain or instability in an accelerated time frame. Previously, no detailed rehabilitation guidelines for nonoperative management of UCL injuries in contact sports have been described. Additionally, few studies exist which report on the inclusion of RTS testing following an injury to the UCL of the elbow, as RTS testing is optimal for determining readiness for sport.

Level of Evidence

4, Case Report.

Conservative Versus Surgical Management of Elbow Medial Ulnar Collateral Ligament Injury: A Systematic Review

Objective

Several studies have been published regarding the treatment of medial ulnar collateral ligament (MUCL) injuries for professional overhead athletes. However, there is a paucity of data regarding non‐professional athletes. The aim of this systematic review was to compare the rate of outcome scores and complications of conservative versus operative treatments both in non‐professional athletes and in non‐sport‐related trauma patients with MUCL lesions.

Methods

A systematic review of the published literature was performed by applying the PRISMA guidelines. A search was conducted using three databases: Medline, Science Direct, and Web of Science. The keywords used were “ulnar collateral ligament injury,” “elbow,” “surgery,” and “conservative treatment”. Patients were divided into three groups: patients who underwent conservative treatment (C‐group), surgical treatment (S‐group), and surgery after a failed conservative treatment (C&S‐group). Clinical outcomes were analyzed: Disability of Arm, Shoulder and Hand (DASH), Conway scale, Carson score, and Kerlan–Jobe Orthopaedic Clinic score (KJOC).

Results

A total of 15 studies were included, evaluating 513 patients. Although good and excellent outcomes were found for most patients during daily and/or sport activities, independently of the type of treatment, the C‐group had better results. Excellent results were found in 98.8% of the C‐group, in 88.1% of the S‐group, and in 87.7% of the C&S‐group. The complication rate in the C‐group was statistically higher compared to the S and C&S groups (P < 0.001). However, its complication rate was higher with lower patient satisfaction.

Conclusions

There is insufficient evidence to establish statistically significant differences in the effects of conservative versus surgical treatments on the functional outcomes of patients with MUCL lesions. However, a period of rehabilitation therapy and the functional request of the single injured subject are useful to discern which patients genuinely require MUCL surgical repair.

Prevalence of Medial Ulnar Collateral Ligament Surgery in 6135 Current Professional Baseball Players: A 2018 Update

Background:

As the incidence of ulnar collateral ligament (UCL) surgery continues to rise rapidly, an update on the current prevalence and demographics in professional baseball players is warranted.

Hypothesis:

The prevalence of UCL reconstruction in Major League Baseball (MLB) and Minor League Baseball (MiLB) players will be higher than that previously reported, and the increase in prevalence will be most notable in MiLB pitchers.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

During the 2018 baseball season, an online questionnaire regarding a history of UCL surgery was distributed to the certified athletic trainers of all 30 MLB organizations. These trainers then administered the survey to all players within their organizations, including MLB, MiLB (AAA, AA, High A, Low A, High Rookie, Low Rookie), and Dominican Summer League (DSL) players. Demographics were compared between MLB, MiLB, and DSL players. Results of this 2018 survey were compared with previously published data from the 2012 season to assess the change over time.

Results:

There were 6135 professional baseball players who completed the survey (66% response rate). The prevalence of UCL reconstruction in all MLB and MiLB players was 13% (637/4928), while the prevalence in DSL players was 2% (20/1207) (P < .001). The prevalence in all MLB and MiLB players (13%) and pitchers (20%) both increased significantly from 2012 (P < .001). MLB pitchers reported a higher prevalence of UCL reconstruction than did MiLB pitchers (26% vs 19%, respectively; P < .001). In 2018, the prevalence of UCL reconstruction has increased significantly in MiLB pitchers (19% vs 15%, respectively; P < .001) and pitchers aged 21 to 30 years (22% vs 17%, respectively; P < .001) compared with 2012. Additionally, United States–born pitchers were more likely to have undergone UCL reconstruction compared with Latin America–born pitchers (23% vs 13%, respectively; P < .001).

Conclusion:

The prevalence of UCL reconstruction has increased significantly in professional baseball players over the past 6 years from 10% to 13%. Ultimately, the prevalence of UCL reconstruction has increased most significantly since 2012 in MiLB pitchers, pitchers aged 21 to 30 years, and pitchers born in the United States.

Do Professional Baseball Players With a Higher Valgus Carrying Angle Have an Increased Risk of Shoulder and Elbow Injuries?

Background:

There are many risk factors for shoulder and elbow injuries in professional baseball pitchers. The elbow carrying angle has not been studied as a potential risk factor.

Purpose/Hypothesis:

The aim of this study was to determine whether elbow carrying angle is a risk factor for shoulder or elbow injuries in professional baseball pitchers. We hypothesized that pitchers with a higher elbow carrying angle would be less likely to sustain an injury during the season than pitchers with a lower elbow carrying angle.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

All professional pitchers for a single baseball club during the 2018 season had the carrying angle of both elbows measured at spring training by a single examiner. The pitchers were followed prospectively throughout the season. Shoulder and elbow injuries were recorded prospectively.

Results:

A total of 52 pitchers (21 [40%] Major League Baseball and 31 [60%] Minor League Baseball) were included. During the season, 23 (44%) pitchers became injured. The mean carrying angle in the throwing arm was 12.5° ± 4.2° versus 9.9° ± 2.8° in the nonthrowing arm (P < .001). Comparing the injured and noninjured groups, there were no differences in level of play (P = .870), throwing hand dominance (P = .683), batting hand dominance (P = .554), throwing-side carrying angle (P = .373), nonthrowing-side carrying angle (P = .773), or side-to-side difference in carrying angle (P = .481).

Conclusion:

The elbow carrying angle was not associated with an injury risk during a single season in professional baseball pitchers.

Deceleration phase elbow varus moments: a potential injury mechanism for collegiate baseball pitchers

The incidence of elbow injury experienced by baseball pitchers is on the rise. Biomechanical investigations focusing on the acceleration phase of the pitch have yet to elucidate a singular cause for these injuries. Leading to the question is there an additional significant stress on the elbow during other phases of the pitch? This study sought to determine the magnitude of the elbow varus moment during the deceleration phase of the pitching cycle for the fastball, curveball, slider and change-up. Eighty-seven collegiate-level pitchers were evaluated using motion analysis techniques to determine the magnitude of the elbow varus moment occurring during the deceleration phase. The results indicated that the elbow varus moment during the deceleration phase of the pitch was typically between 40% and 50% of the peak acceleration phase moment and was greatest when throwing a slider. Results also indicated that more pitchers experienced deceleration phase moments in excess of 50% of the acceleration moment when throwing breaking pitches. These moments which are the result of the pitchers' need to rapidly decelerate their arm produce an additional significant elbow varus moment that results in additional stress to the elbow.

Open Reduction Internal Fixation of Medial Epicondyle Fractures After Ulnar Collateral Ligament Reconstruction in Professional Baseball Pitchers

Background:

Ulnar collateral ligament reconstruction (UCLR) is a common procedure among professional baseball pitchers. An uncommon complication after UCLR is a fracture of the medial epicondyle at the level of the humeral tunnel, which requires open reduction internal fixation (ORIF).

Purpose/Hypothesis:

The purpose of this study was to determine the performance upon and rate of return to sport (RTS) in professional baseball pitchers after ORIF of the medial epicondyle and examine whether there is a difference in the RTS rate and performance between players who underwent ORIF and matched controls. It was hypothesized that there would be a high rate of RTS in professional baseball pitchers after ORIF of the medial epicondyle, with no difference between the ORIF and control groups in the rate of RTS or performance, specifically related to the primary performance outcome variables of win-loss percentage, walks plus hits per inning pitched, fielding independent pitching, and wins above replacement.

Methods:

All professional baseball pitchers who underwent ORIF of the medial epicondyle between 2010 and 2016 were included in this study. Demographic and performance data (preoperative and postoperative) were recorded for each player. Performance metrics were then compared between the ORIF and control (no history of UCLR or ORIF) groups.

Results:

Overall, 15 pitchers (80.0% starters, 73.3% right-handed) underwent ORIF of a medial epicondyle fracture. All had undergone prior UCLR using either the American Sports Medicine Institute (n = 9; 60.0%) or docking (n = 6; 40.0%) technique. ORIF techniques included fixation with 1 screw (n = 13; 86.7%) and fixation with suture anchors (n = 2; 13.3%). Eleven (73.3%) pitchers were able to return to sport (did not differ from controls; P = .537); 55% returned to the same level or higher. No significant differences existed in the primary performance outcome variables when comparing preoperative with postoperative performance. No significant differences in the primary performance outcome variables were seen between the ORIF and control groups after surgery, although players in the ORIF group pitched fewer innings than controls after surgery (P = .003).

Conclusion:

After ORIF of the medial epicondyle in professional pitchers with a history of UCLR, 73.3% were able to return to sport (only 55% of those who returned pitched at the same level or higher) without a significant decline in most performance variables when compared with their preoperative performance or matched controls. The number of innings pitched declined after surgery.

Elbow flexion post ball release is associated with the elbow varus deceleration moments in baseball pitching

The association between breaking pitches and elbow injury remains nebulous. Biomechanical studies have shown that throwing a fastball rather than a curveball results in greater elbow moments, despite some epidemiological studies and pitcher self-report indicating the opposite. This leads to the following question: Are biomechanical studies missing something that could explain this discrepancy? This study evaluated the association between elbow kinematics of baseball pitchers during the deceleration phase of the pitch and the elbow varus moment. Eighty-seven uninjured collegiate pitchers were analysed using 3-dimensional motion capture techniques. Results indicated that pitchers who remained in greater elbow flexion had greater post ball release elbow varus moments (EVMPBR) (p = 0.001). Regression analysis indicated that for every 10° of increased elbow flexion during follow-through the EVMPBR increased by 5.4 Nm for the fastball and 8.2 Nm for the curveball (p < 0.001). This suggests a concerning second stress on the elbow joint occurring during the deceleration phase of the pitch. The results showed that maintaining greater elbow flexion during the deceleration phase of the pitch can substantially increase the elbow varus moment after ball release (BR), especially when pitching the curveball. The results reinforce the need to emphasise appropriate pitching mechanics.

Ulnar collateral ligament injuries of the elbow in female division I collegiate gymnasts: a report of five cases

Introduction

Elbow ulnar collateral ligament (UCL) injuries in gymnastics have not been well documented in the literature, in comparison to UCL injuries in baseball. Few studies have examined the mechanism and nonoperative management of this injury, and no studies to date have been published on incidence of injury and return to play recommendations in gymnastics.

Patient case review

A literature search was performed using PubMed to review articles from 1980 to 2016 that addressed the biomechanics of UCL injury in baseball and gymnastics, the anatomy of the elbow, injury rates, surgical vs non-surgical management, rehabilitation, and return to play recommendations for the sport of gymnastics. Five female collegiate gymnasts sustained UCL injury over a 3-year period. Electronic medical records for each case were thoroughly reviewed including imaging, surgical and non-surgical management, rehabilitation, and the progressive return to gymnastics.

Discussion

Four UCL injuries were confirmed by MRI to be avulsions at the distal insertion of the UCL and one was an avulsion at the proximal origin. While less than half of baseball players can return to competition with conservative management of these types of injuries, four out of five gymnasts were able to return to competition with nonoperative management. One gymnast opted to have reconstruction after a successful competition season. Time to return to play varied seemingly dependent on the severity of UCL injury and event.

Conclusion

In our case series, collegiate female gymnasts were able to return to participation with nonoperative treatment of the UCL. Their success in returning to competitive gymnastics may also depend on the event(s) in which they are trying to participate.

Strength of Recommendation Taxonomy

C.

Return to Play After PRP and Rehabilitation of 3 Elite Ice Hockey Players With Ulnar Collateral Ligament Injuries of the Elbow

Background:

Ulnar collateral ligament (UCL) injury is a well-described etiology of pain and decreased performance for the overhead athlete. Despite a growing volume of literature regarding the treatment of these injuries for overhead athletes, there is a paucity of such data regarding stickhandling collision sport athletes, such as ice hockey players.

Purpose/Hypothesis:

The purpose of this study was to characterize this injury among 3 elite ice hockey players and to describe the ability of these athletes to return to play, as well as to review the unique sport-specific implications of this injury, evaluation, nonsurgical management, and considerations for return to play. The authors hypothesized that elite ice hockey players will be able to return to play at the same level following nonoperative treatment of UCL injury.

Study Design:

Case series; Level of evidence, 4.

Methods:

Data from 3 elite professional ice hockey players who sustained a high-grade injury to the UCL were retrospectively reviewed. All athletes underwent 2 autologous conditioned plasma injections as part of their treatment and were evaluated with ultrasonography and magnetic resonance imaging.

Results:

Three consecutive elite ice hockey players were included in this study, and no patients were excluded. Players were cleared to full return to play at a mean 36 days postinjury. Follow-up examination at this time point demonstrated full range of motion of the elbow for all athletes, without tenderness to palpation over the UCL, including no tenderness over the humeral insertion site. Stability examination improved as well, demonstrating a soft to moderate endpoint with valgus stress, although this was not symmetric to the contralateral side. All athletes were able to continue to play at the same level of competition as before the injury occurred, without any complaints. No players had repeat injury during the same or following seasons.

Conclusion:

The authors present 3 elite-level ice hockey players who sustained a high-grade injury to the UCL. Successful return to play was possible after nonoperative treatment with injection of autologous conditioned plasma at a mean 36 days following injury. Athletes who injure either the top or bottom hand can return to play at the same elite level following this injury.

Understanding the medial ulnar collateral ligament of the elbow: Review of native ligament anatomy and function

The medial ulnar collateral ligament complex of the elbow, which is comprised of the anterior bundle [AB, more formally referred to as the medial ulnar collateral ligament (MUCL)], posterior (PB), and transverse ligament, is commonly injured in overhead throwing athletes. Attenuation or rupture of the ligament results in valgus instability with variable clinical presentations. The AB or MUCL is the strongest component of the ligamentous complex and the primary restraint to valgus stress. It is also composed of two separate bands (anterior and posterior) that provide reciprocal function with the anterior band tight in extension, and the posterior band tight in flexion. In individuals who fail comprehensive non-operative treatment, surgical repair or reconstruction of the MUCL is commonly required to restore elbow function and stability. A comprehensive understanding of the anatomy and biomechanical properties of the MUCL is imperative to optimize reconstructive efforts, and to enhance clinical and radiographic outcomes. Our understanding of the native anatomy and biomechanics of the MUCL has evolved over time. The precise locations of the origin and insertion footprint centers guide surgeons in proper graft placement with relation to bony anatomic landmarks. In recent studies, the ulnar insertion of the MUCL is described as larger than previously thought, with the center of the footprint at varying distances relative to the ulnar ridge, joint line, or sublime tubercle. The purpose of this review is to consolidate and summarize the existing literature regarding the native anatomy, biomechanical, and clinical significance of the entire medial ulnar collateral ligament complex, including the MUCL (AB), PB, and transverse ligament.

Following ulnar collateral ligament reconstruction, professional baseball position players return to play faster than pitchers, but catchers return less frequently

BACKGROUND

Although much as been done to characterize trends of medial ulnar collateral ligament (UCL) reconstruction in pitchers, outcomes in position players (PPs) (non-pitchers) remain undefined in the current literature.

METHODS

Three resources were combined to identify all known Major League Baseball and Minor League Baseball (MiLB) PPs who have ever undergone UCL reconstruction. A multitude of player and surgical variables were included. Trends over time were analyzed collectively, based on level of play, revision status (primary vs revision), and position. Additional comparisons were made with a known cohort of professional baseball pitchers having undergone UCL reconstruction.

RESULTS

We identified 168 UCL reconstructions in professional PPs. The annual rate of primary UCL reconstruction rose significantly from 1984 to 2015 (P < .001), and the proportion of cases performed in MiLB PPs (vs Major League Baseball PPs) increased steadily (P < .001). Of PPs, 75.5% returned to play at any level at a mean of 342 days. Catchers demonstrated the lowest return-to-play (RTP) rate (58.6%) compared with infielders (75.6%) and outfielders (88.9%). The overall revision rate was low, at 4.8%. Compared with pitchers, PPs demonstrated a lower rate of RTP (75.5% for PPs vs 83.7% for pitchers, P = .040) but shorter RTP times for those able to return (342 days for PPs vs 435 days for pitchers, P < .001).

CONCLUSIONS

The incidence of UCL reconstruction in PPs continues to rise, a trend that is significantly more pronounced at the MiLB level. Although PPs (particularly catchers) are less likely to return to professional baseball compared with pitchers, those who are able to RTP do so more rapidly.

Clinical Outcome of Arthroscopic Treatment for Posteromedial Elbow Impingement in Adolescent Baseball Players

PURPOSE

To evaluate the clinical outcomes of arthroscopic treatment in adolescent baseball players with posteromedial elbow impingement.

METHODS

This retrospective study evaluated the clinical outcome of arthroscopic treatment for posteromedial elbow impingement in adolescent baseball players. Patients were eligible for participation if they had undergone surgery at least 2 years earlier and excluded if they had arthritis, loose bodies, osteochondritis dissecans, ulnar collateral ligament tear, flexor/pronator injuries or medial epicondylitis, or nerve problems. Patients were also excluded if they had undergone prior elbow surgery, were younger than 13 years, or were older than 19 years. Arthroscopic treatment included debridement of posteromedial synovitis, fragment removal, and olecranon spur excision. At a mean follow-up of 26.7 (range 24-42) months, patients were evaluated based on a questionnaire, examination, and the previously reported elbow outcome score.

RESULTS

This retrospective study involved 15 male patients, comprising 6 pitchers, 3 catchers, and 6 fielders, of mean age 15.7 (range 14-17) years. Mean time from onset of symptoms to surgery was 4.9 (range 3-18) months. Intraoperative findings included posteromedial synovitis and olecranon spurs in all patients and fragments in 10. The elbow outcome score was considered excellent in 11 patients and good in 2, with a mean score of 92 points (maximum 100 points). The mean postoperative range of motion at the elbow was 5° to 139.7° of flexion. All patients were able to return to their previous level of play after an average of 3.4 (range 2.5-4.5) months. No patient developed medial instability that later required reconstructive surgery.

CONCLUSIONS

Arthroscopic debridement, excision of the olecranon spur, and removal of fragments yield reliable subjective and objective results and allow a return to baseball in adolescent patients.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

The Relationship of Throwing Arm Mechanics and Elbow Varus Torque: Within-Subject Variation for Professional Baseball Pitchers Across 82,000 Throws

BACKGROUND

Likely due to the high level of strain exerted across the elbow during the throwing motion, elbow injuries are on the rise in baseball. To identify at-risk athletes and guide postinjury return-to-throw programs, a better understanding of the variables that influence elbow varus torque is desired.

PURPOSE

To describe the within-subject relationship between elbow varus torque and arm slot and arm rotation in professional baseball pitchers.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 81 professional pitchers performed 82,000 throws while wearing a motusBASEBALL sensor and sleeve. These throws represented a combination of throw types, such as warm-up/catch, structured long-toss, bullpen throwing from a mound, and live game activity. Variables recorded for each throw included arm slot (angle of the forearm relative to the ground at ball release), arm speed (maximal rotational velocity of the forearm), arm rotation (maximal external rotation of the throwing arm relative to the ground), and elbow varus torque. Linear mixed-effects models and likelihood ratio tests were used to estimate the relationship between elbow varus torque and arm slot, arm speed, and arm rotation within individual pitchers.

RESULTS

All 3 metrics-arm slot (χ² = 428, P < .001), arm speed (χ² = 57,683, P < .001), and arm rotation (χ² = 1392, P < .001)-were found to have a significant relationship with elbow varus torque. Within individual athletes, a 1-N.m increase in elbow varus torque was associated with a 13° decrease in arm slot, a 116 deg/s increase in arm speed, and an 8° increase in arm rotation.

CONCLUSION

Elbow varus torque increased significantly as pitchers increased their arm rotation during the arm cocking phase, increased the rotational velocity of their arm during the arm acceleration phase of throwing, and decreased arm slot at ball release. Thus, shoulder flexibility, arm speed, and elbow varus torque (and likely injury risk) are interrelated and should be considered collectively when treating pitchers.

CLINICAL RELEVANCE

It is well established that elbow varus torque is related to ulnar collateral ligament injuries in overhead throwers. This study describes the relationship of arm slot, arm speed, and arm rotation to elbow varus torque in an attempt to identify modifiable risk factors for injury.

Pathologies of the shoulder and elbow affecting the overhead throwing athlete

The overhead-throwing athlete is susceptible to a variety of predictable disease entities affecting the shoulder and elbow. While the pathophysiology and nomenclature of these diseases are ubiquitous throughout the clinical literature, this information is sparse within the radiology domain. We provide a comprehensive review of these unique injuries with accompanying imaging features in an effort to enhance the role of the radiologist during the management of the overhead thrower. When appropriately recognized and described, the imaging features aid in establishing a diagnosis and ultimately the implementation of appropriate clinical management.

Treatment of Ulnar Collateral Ligament Tears of the Elbow: Is Repair a Viable Option?

BACKGROUND

Ulnar collateral ligament (UCL) tears have become common, and UCL reconstruction (UCLR) is currently the preferred surgical treatment method for treating UCL tears.

PURPOSE/HYPOTHESIS

The purpose of this study was to review the literature surrounding UCL repair and determine the viability of new repair techniques for treatment of UCL tears. We hypothesized that UCL repair techniques will provide comparable results to UCLR for treatment of UCL tears.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

A systematic review was registered with PROSPERO and performed with PRISMA guidelines using 3 publicly available free databases. Biomechanical and clinical outcome investigations reporting on UCL repair with levels of evidence 1 through 4 were eligible for inclusion. Descriptive statistics were calculated for each study and parameter/variable analyzed.

RESULTS

Of the 46 studies eligible, 4 studies (3 clinical and 1 biomechanical) were included. There were 92 patients (n = 92 elbows; 61 males [62.3%]; mean age, 21.9 ± 4.7 years) included in the clinical studies, with a mean follow-up of 49 ± 14.4 months. Eighty-six percent of repairs performed were on the dominant elbow, and 38% were in college athletes. Most UCL repairs (66.3%) were performed via suture anchors. After UCL repair, 87.0% of patients were able to return to sport. Overall, 94.9% of patients scored excellent/good on the Andrews-Carson score. Patients who were able to return to sport after UCL repair did so within 6 months after surgery. Biomechanically, when UCL repair was compared with the modified Jobe technique, the repair group showed significantly less gap formation than the reconstruction group.

CONCLUSION

In patients for whom repair is properly indicated, UCL repair provides similar return-to-sport rates and clinical outcomes with shorter return-to-sport timing after repair compared with UCL reconstruction. Future outcome studies evaluating UCL repair with internal bracing are necessary before recommending this technique.

Elbow Imaging in Sport: Sports Imaging Series

Elbow pain is a frequent presenting symptom in athletes, particularly athletes who throw. The elbow can be injured as a result of acute trauma, such as a direct blow or a fall onto an outstretched hand or from chronic microtrauma. In particular, valgus extension overload during the throwing motion can precipitate a cascade of chronic injuries that can be debilitating for both casual and high-performance athletes. Prompt imaging evaluation facilitates accurate diagnosis and appropriate targeted interventions.

The effect of age on elbow range of motion in pitchers

BACKGROUND

Alteration of elbow range of motion (ROM) has been observed in baseball pitchers. This study aims to compare dominant elbow ROM between early-puberty, late-puberty, and young-adult pitchers.

METHODS

We recruited 62 pitchers, consisting of 17 early-puberty (mean age 13.1 years old), 22 late-puberty (mean age 17.7 years old), and 23 young-adult players (mean age 19.4 years old). Dominant elbow ROMs was measured. One-way ANOVA was used to compare the differences in elbow ROM variables between 3 groups.

RESULTS

Late-puberty pitchers exhibited a significantly lower elbow hyperextension and flexion than early-puberty or young-adult pitchers (P < .05). Valgus angle was significantly lower in young-adult (7.7°±5.5°) versus early-puberty (12.1°±2.3°) and late-puberty pitchers (13.0°±4.1°; P < .05). Young-adult pitchers had the largest forearm supination range (101.2°±18.1°), followed by early-puberty (82.5°±6.5°; P < .05) and late-puberty pitchers (70.6°±15.8°). Elbow flexion-hyperextension total range was smallest in late-puberty pitchers (130.3°±7.4°), followed by young-adult (142.6°±9.3°) and early-puberty pitchers (144.6°±8.3°; P < .05). Forearm pronation-supination total range was also smallest in late-puberty pitchers (142.0°±20.3°), followed by early-puberty (159.8°±9.5°) and young-adult pitchers (177.2°±20.8°; P < .05).

CONCLUSIONS

These results indicate that careful monitoring of the elbow and forearm range of motion should be undertaken in adolescent baseball pitchers to prevent and or minimize injury risk.

Ulnar Collateral Ligament Reconstruction: Anatomy, Indications, Techniques, and Outcomes

Context:

Ulnar collateral ligament (UCL) injuries lead to pain and loss of performance in the thrower’s elbow. Ulnar collateral ligament reconstruction (UCLR) is a reliable treatment option for the symptomatic, deficient UCL. Injury to the UCL usually occurs because of chronic accumulation of microtrauma, although acute ruptures occur and an acute-on-chronic presentation is also common.

Evidence Acquisition:

Computerized databases, references from pertinent articles, and research institutions were searched for all studies using the search terms ulnar collateral ligament from 1970 until 2015.

Study Design:

Clinical review.

Level of Evidence:

Level 5.

Results:

All studies reporting outcomes for UCLR are level 4. Most modern fixation methodologies appear to be biomechanically and clinically equivalent. Viable graft choices include ipsilateral palmaris longus tendon autograft, gracilis or semitendinosus autograft, and allograft. Clinical studies report excellent outcomes of UCLR for both recreational and elite level athletes with regard to return to sport and postoperative performance. Complications, although rare, include graft rerupture or attenuation, ulnar nerve symptoms, stiffness, pain, and/or weakness leading to decreased performance.

Conclusion:

Injuries to the UCL have become commonplace among pitchers. Nonoperative treatment should be attempted, but the limited studies have not shown promising results. Operative treatment can be performed with several techniques, with retrospective studies showing promising results. Complications include ulnar neuropathy as well as failure to return to sport. Detailed preoperative planning, meticulous surgical technique, and a comprehensive rehabilitation program are essential components to achieving a satisfactory result.

Ulnar Collateral Ligament and Elbow Adaptations in High School Baseball Pitchers

BACKGROUND

Baseball pitchers have adaptive changes in the soft tissues of the throwing elbow.

HYPOTHESIS

High school baseball pitchers would show adaptive changes in the ulnar collateral ligament (UCL), such as calcifications and hypoechoic foci, thickening, and increased ulnohumeral joint laxity, on dynamic ultrasound (DUS).

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Twenty-two asymptomatic high school pitchers, designated as their primary position by their coach, underwent DUS and physical examination of the throwing and nonthrowing elbows prior to the start of the season. UCL substance consistency and thickness, ulnohumeral joint space widening, and soft tissue elbow structures were evaluated.

RESULTS

The mean age of the cohort was 16.9 years. Calcifications of the UCL were similar, being present in 7 of 22 (32%) throwing elbows versus 8 of 22 (36%) nonthrowing elbows (P = 0.11). UCL hypoechoic foci also were similar between elbows: 2 of 22 (9%) throwing elbows versus 0 of 22 nonthrowing elbows (P = 0.11). UCL thickness was also found to be similar in both elbows (throwing arm, 6.54 mm vs nonthrowing, 6.71 mm; P = 0.48). Ulnohumeral joint laxity unloaded (throwing arm, 3.13 mm vs nonthrowing, 3.17 mm; P = 0.835) and loaded (throwing arm, 3.87 mm vs nonthrowing arm, 4.11 mm; P = 0.30) was similar between elbows. Throwing elbows showed posteromedial olecranon spurring in 36%, effusions in 27%, and synovitis in 9%.

CONCLUSION

High school pitchers show limited adaptive changes in the elbow, including UCL calcifications, hypoechoic foci, posteromedial olecranon spurring, and effusions. However, these changes are similar to those seen in the nonthrowing elbow, and these younger athletes lack findings seen in professional and collegiate pitchers such as UCL thickening and increased ulnohumeral joint space laxity.

CLINICAL RELEVANCE

Preseason ultrasound examination of the high school pitching elbow lacks the adaptive changes to the elbow as seen in professional pitchers. These changes likely occur later in a pitcher's career.

The thrower's elbow

Overhead throwing activities expose the elbow to tremendous valgus stress, making athletes vulnerable to a specific constellation of injuries. Although baseball players, in particular pitchers, are the athletes affected most commonly, overhead throwing athletes in football, volleyball, tennis, and javelin tossing also are affected. The purpose of this review is to review the anatomy, biomechanics, pathophysiology, and treatment of elbow disorders related to overhead throwing athletes. Although focus is on management of ulnar collateral ligament injuries, all common pathologies are discussed.

Upper body contributions to power generation during rapid, overhand throwing in humans

High-speed and accurate throwing is a distinctive human behavior. Achieving fast projectile speeds during throwing requires a combination of elastic energy storage at the shoulder, as well as the transfer of kinetic energy from proximal body segments to distal segments. However, the biomechanical bases of these mechanisms are not completely understood. We used inverse dynamics analyses of kinematic data from 20 baseball players fitted with 4 different braces that inhibit specific motions to test a model of power generation at key joints during the throwing motion. We found that most of the work produced during throwing is generated at the hips, and much of this work (combined with smaller contributions from the pectoralis major) is used to load elastic elements in the shoulder and power the rapid acceleration of the projectile. Despite rapid angular velocities at the elbow and wrist, the restrictions confirm that much of the power generated to produce these distal movements comes from larger proximal segments, such as the shoulder and torso. Wrist hyperextension enhances performance only modestly. Together, our data also suggest heavy reliance on elastic energy storage may help explain some common throwing injuries and can provide further insight into the evolution of the upper body and when our ancestors first developed the ability to produce high speed throws.

Elbow ulnar collateral ligament reconstruction in javelin throwers at a minimum 2-year follow-up

BACKGROUND

There are several large series of outcomes after ulnar collateral ligament (UCL) reconstruction that have 1 or 2 javelin throwers included. To our knowledge, however, there are no reports that focus solely on the results of UCL reconstruction in this group of athletes.

HYPOTHESIS/PURPOSE

We hypothesize that by using modern UCL reconstruction techniques, javelin throwers can reliably expect to return to their sport. Additionally, we review the principles behind postoperative rehabilitation in these athletes, as it differs from the usual approach used with baseball players.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This was a retrospective review of 10 javelin throwers who underwent UCL reconstruction between 2006 and 2009 using the docking technique. There were 5 college and 5 high school javelin throwers. The average age was 18.5 years (range, 18-21 years). All patients, before being indicated for ligament reconstruction, failed a course of nonoperative management that included rest, physical therapy, and a structured attempt to return to throwing. Postoperatively, patients were evaluated using the Conway Scale and the Andrews-Timmerman Score.

RESULTS

Patients were evaluated at a minimum 2-year follow-up. The average follow-up was 28.9 months after surgery (range, 24-45 months). On the Conway Scale, 9 of the 10 players had excellent outcomes (90%). There was one fair (10%) outcome. Average time to return to previous level of competition was 15 months. The mean Andrews-Timmerman Score was 97 (range, 85-100). Overall, 100% (10/10) of the patients were subjectively satisfied with their clinical outcome.

CONCLUSION

Similar to other overhand athletes with UCL insufficiency, javelin throwers can reliably expect to return to their previous level of play after surgical reconstruction. A thorough understanding of the unique demands placed on these athletes because of the different throwing motion is helpful when tailoring their postoperative rehabilitation protocol. Additionally, these athletes must be counseled that the postoperative course is associated with an extended period of time until return to previous level of competition when compared with baseball players.

Posteromedial elbow impingement: magnetic resonance imaging findings in overhead throwing athletes and results of arthroscopic treatment

PURPOSE

The purpose of this study was to define the magnetic resonance imaging (MRI) pattern and assess the results of arthroscopic treatment of posteromedial elbow impingement in overhead throwers.

METHODS

Over an 8-year period, 9 throwing athletes diagnosed with posteromedial elbow impingement were retrospectively identified. All patients had either a noncontrast or direct arthrogram-MRI study that was reviewed by a single, fellowship-trained musculoskeletal radiologist blinded to the clinical diagnosis. Arthroscopic treatment included debridement of posteromedial synovitis, loose body removal, and excision of the olecranon spur. All patients underwent a physical examination and completion of the Andrews-Carson scale at a mean of 68 months (range, 25 to 112 months).

RESULTS

All patients were male, with a mean age of 21.0 years (range, 17 to 34 years). The dominant arm was affected in all patients. The mean length of symptoms before surgery was 9 months (range, 5 to 24 months). At MRI, a reproducible pattern of pathology was noted. All patients had pathology at the articular surfaces of the posterior trochlea and the anterior, medial olecranon. The findings ranged from abnormal edema-like signal in the hyaline cartilage to cartilage defects and subjacent, subchondral bone marrow edema. Findings at surgery included posteromedial synovitis and olecranon spurring in all patients and loose bodies in 3 patients. On the basis of the Andrews-Carson scale, the subjective and objective outcome was considered excellent in 7 patients and good in 2.

CONCLUSIONS

Posteromedial elbow impingement is a source of disability in the overhead throwing athlete. Correlation of history and physical examination with imaging findings is essential to confirm the diagnosis. This study indicates that MRI identifies a reproducible pattern of pathology in throwing athletes with this disorder. These MRI findings correlate highly with arthroscopic evaluation. Arthroscopic debridement, olecranon spur excision, and loose body removal allow return to throwing sports and reliable subjective and objective results in carefully selected patients.