The success of return to sport after ulnar collateral ligament injury in baseball: a systematic review and meta-analysis

Variable Return to Play and Sport Performance After Elbow Ulnar Collateral Ligament Reconstruction in Baseball Players: A Systematic Review

PURPOSE

To evaluate return to play (RTP) and return to same level of play (RTSP) rates as well as preoperative and postoperative in-game performance metrics in baseball pitchers who underwent ulnar collateral ligament reconstruction (UCLR). Secondarily, this review sought to assess outcomes based on primary versus revision UCLR as well as level of competition.

METHODS

This review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, Embase, Web of Science, and Cochrane Database of Systematic Reviews were queried to identify articles evaluating UCLR in baseball players between January 2002 and October 2022. Data included RTP, RTSP, and performance metrics including earned run average, innings pitched, walks and hits per inning pitched, batting average against, strikeouts per 9 innings, walks per 9 innings, percentage of fastballs thrown, and average fastball velocity. The Methodological Index for Non-randomized Studies criteria were used for quality assessment.

RESULTS

Analysis included 25 articles reporting on 2,100 elbows. After primary UCLR, RTP ranged from 336 to 615 days (57% to 100% achieved) and RTSP ranged from 330 to 513 days (61% to 95%). After revision UCLR, RTP ranged from 381 to 631 days (67% to 98%) and RTSP ranged from 518 to 575 days (42% to 78%). When stratifying primary UCLR outcomes by competitive level, RTP and RTSP ranged respectively from 417 to 615 days (75% to 100%) and 513 days (73% to 87%) for Major League Baseball only, 409 to 615 days (57% to 100%) and 470 to 513 days (61% to 95%) for Major League Baseball plus Minor League Baseball, and 336 to 516 days (73% to 85%) and 330 days (55% to 74%) for college plus high school. Heterogeneity was seen in postoperative sports performance metrics.

CONCLUSIONS

Although more than half of baseball players appear able to RTP after primary and revision UCLR, RTSP rates after revision UCLR were as low as 42% in the literature. Preoperative and postoperative performance metrics varied.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II-IV studies.

A systematic review of the outcomes of partial ulnar collateral ligament tears of the elbow in athletes treated non-operatively with platelet-rich plasma injection

Background

This study aimed to analyze the effects of platelet-rich plasma (PRP) for partial ulnar collateral ligament (UCL) tears in athletes and predicted positive outcomes.

Methods

The researchers systematically reviewed the PubMed, Cochrane CENTRAL, MEDLINE, Scopus, and Google Scholar databases to identify studies with clinical outcomes of PRP for partial UCL tears. They excluded studies that did not stratify data by tear type or included surgical management.

Results

Five studies with 156 patients were included. The timing, amount, platelet concentration, type, and number of PRP injections were highly variable among the studies. However, 75% (n = 97/127) of athletes returned to sport (RTS) at a weighted average of 82.1 days (37-84) after PRP injection. One study showed significant improvements in patient-reported outcomes. Two studies showed positive outcomes in the modified Conway scale, complete reconstitution of the UCL in 87% of patients on MRI, and significant improvement in the humeral-ulnar joint space after PRP injection via ultrasound. The Coleman methodology score (CMS) averaged 48/100, indicating an overall poor quality of evidence.

Conclusion

This review demonstrates favorable RTS, clinical, and radiographic outcomes in patients receiving PRP for partial UCL tears, but the literature remains heterogeneous and of low quality.

Level of Evidence

III.

Elbow valgus stress during towel drills in college baseball players

BACKGROUND

In baseball players with elbow injuries, towel drills are clinically used before initiating active throwing exercises to gradually increase stress across the elbow. However, elbow valgus torque during towel drills remains unknown. Moreover, towel drills and active ball throws might have different relationships between biomechanical metrics, such as elbow stress, arm slot, and arm speed. Therefore, the aims of this study were 1) to demonstrate the difference in elbow valgus stress between towel drills and active ball throws and 2) to evaluate the correlation between elbow valgus torque and other biomechanical metrics including arm slot and arm speed in towel drills and active ball throws.

METHODS

Seventeen healthy college baseball players performed three towel drills using a face towel, short foam tube, and long foam tube, followed by full-effort throwing on flat ground. Each participant completed five consecutive trials of each task, and the elbow valgus torque, arm slot, and arm speed were measured using wearable sensors. One-way repeated analysis of variance and post-hoc tests were used to determine the differences in biomechanical metrics among the tasks. Furthermore, the correlation between the elbow valgus torque and other metrics was evaluated using Pearson correlation coefficients.

RESULTS

Elbow valgus torque was lower in towel drills compared to that of active ball throws; however, the stress during towel drills using a face towel reached almost 80% of the maximum effort of active ball throws. There was no relationship between elbow valgus stress and arm slot in either the towel or active ball throw tasks. However, a higher arm speed was associated with greater elbow valgus torque in towel drills, whereas no relationship between elbow stress and arm speed was found in active ball throws.

CONCLUSION

Precaution must be taken in athletes following a progressive throwing program because elbow valgus stress reaches almost 80% of the full-effort throw, even when using a face towel in a towel drill. Hence, the subjective intensity must be controlled even in towel drills to gradually increase the medial elbow stress. Moreover, the mechanisms underlying changes in elbow stress may differ between towel drills and active ball throws. Future investigations on the difference between towel drills and active ball throws may help understand the underlying mechanism of alterations in elbow valgus torque during the throwing movement.

Evaluation of Spin in the Abstracts of Systematic Reviews and Meta-Analyses of Ulnar Collateral Ligament Reconstruction

Purpose

To identify the quantity and types of spin present in systematic reviews and meta-analyses of ulnar collateral ligament reconstruction (UCLR) outcomes and to characterize the studies with spin to determine if any patterns exist.

Methods

This study was conducted per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. In August 2022, PubMed, Scopus, and SportDiscus databases were searched using the terms "ulnar collateral ligament reconstruction" AND "systematic review" OR "meta-analysis." Each abstract was assessed for the presence of the 15 most common types of spin derived from a previously established methodology. General data that were extracted included study title, authors, publication year, journal, level of evidence, study design, funding source, reported adherence to PRISMA guidelines, preregistration of the study protocol, and methodologic quality per A Measurement Tool to Assess Systematic Reviews Version 2 (AMSTAR 2).

Results

In total, 122 studies were identified during the preliminary search, of which 19 met the inclusion criteria. Each study had at least 1 form of spin. The most common type of spin identified was type 5 ("The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies") (7/19, 36.8%). AMSTAR type 9 ("Did the review authors use a satisfactory technique for assessing the RoB [risk of bias] in individual studies that were included in the review?") was associated with both a lower Clarivate Impact Factor (P = .001) and a lower Scopus CiteScore (P = .015). Studies receiving external funding were associated with the failure to satisfy AMSTAR type 3 ("Did the review authors explain their selection of the study designs for inclusion in the review?") (P = .047).

Conclusions

Spin is highly prevalent in the abstracts of systematic reviews and meta-analyses that investigate the outcomes of UCLR.

Clinical Relevance

Spin has been identified in peer-reviewed articles published on various topics, including many in orthopaedics. Systematic reviews and meta-analyses contain the most comprehensive evidence regarding a clinical question, so it is important to identify spin that may be included in these reports. Greater efforts are needed to ensure that the abstracts of papers accurately represent the results in the full text.

Organizational risk profiling and education associated with reduction in professional pitching arm injuries: a natural experiment

Background

Risk profiling and education are strategies implemented to help reduce injury risk; however, currently. there is little evidence on the effect of these interventions on injury incidence. The purpose of this study was to evaluate the influence of risk profiling and education on upper extremity injury incidence in minor league (MiLB) pitchers and to stratify by injury severity.

Methods

A prospective natural experiment study was conducted from 2013 to 2019 on MiLB pitchers. Beginning in the 2015 season, pitchers were examined and risk profiled for upper extremity injury. Shoulder external, internal, total range of motion, horizontal adduction, and humeral torsion were measured. Organizational risk profiling and education was implemented starting in 2015, based on preseason assessments. Chi-squared test was performed to investigate potential differences between shoulder range of motion risk categories between 2013-2014 (pre) and 2015-2019 (post) seasons. Interrupted time series analyses were performed to assess the association between organizational risk profiling and education on arm injury in MiLB pitchers and were repeated for 7-27 and 28+ day injury severity.

Results

297 pitchers were included (pre: 119, post: 178). Upper extremity injury incidence was 1.5 injuries per 1000 athletic exposures. Pitchers in the 2015-2019 seasons demonstrated increased preseason shoulder injury risk for internal (P = .003) and external (P = .007), while the 2013-2014 seasons demonstrated greater horizontal adduction risk (P = .04). There were no differences between seasons for total range of motion risk (P =.76). Risk profiling and education resulted in an adjusted time loss upper extremity injury reduction for the 2015-2019 seasons (0.68 (95% CI: 0.47, 0.99)), which impacted 7-27 days (0.62 (95% CI: 0.42, 0.93)) but not for 28+ days (0.71 (95% CI: 0.47, 1.06)) time loss. There was no reduction in combined trunk and lower extremity injuries for the 2015-2019 seasons (1.55 (95% CI: 0.79, 3.01)).

Conclusions

Organizational risk profiling and education appear to reduce professional pitching overall and 7-27-day upper extremity injury risk by 33%-38%. There was no difference in trunk and lower extremity injuries over the period, strengthening the reduction in upper extremity injury risk results. This suggests that while injury risk increased over time, organizational risk profiling mitigated the expected increase in upper extremity injury rates. Risk profiling and education can be used as a clinical screening and intervention tool to help decrease upper extremity injuries in professional baseball populations.

High return to sport rate and good patient-reported outcomes in recreational athletes following simple elbow dislocations

BACKGROUND

The purpose of this study was to investigate outcomes and return to sport metrics in recreational athletes who suffered simple elbow dislocations and were treated operatively or nonoperatively.

METHODS

The study included patients between the ages of 16 and 65 who were recreational athletes and had experienced a simple elbow dislocation, with at least 2 years having passed since the injury. Patient-reported outcomes including Mayo Elbow Performance Score (MEPS), Subjective Elbow Value (SEV), Oxford Elbow Score (OES) and Visual Analog Scale (VAS) were collected. Return to sport metrics were assessed.

RESULTS

A total of 44 patients (21 females, mean age 43.8 years [95% CI, 39.1-48.5]) who were recreational athletes before their injury completed follow-up at mean 7.6 years (95% CI, 6.7-8.5). There were 29 patients (65.9%) who were treated operatively. Mean MEPS was 93.3 (95% CI, 90.2-96.4), mean SEV was 94.9 (95% CI, 91.9-97.9) and mean OES was 43.3 (95% CI, 41.3-45.4). A total of 36 (81.8%) patients returned to their pre-injury sport. Mean time to return to sport was 21.7 (95% CI, 16.8-26.5) weeks. There was a significant difference in OES (P = .019) and SEV (P = .030) that favored the nonoperative group; however, no significant differences for MEPS, VAS, satisfaction, arc of motion and return to sport were present between groups. A total of five (11.4%) complications were observed and one (2.3%) required revision.

CONCLUSIONS

Good outcomes and a high return to sport rate can be expected in recreational athletes following operative and nonoperative treatment of simple elbow dislocations. However, as many as one-in-five patients may not return to pre-injury sport.

Shoulder Range of Motion Measurements and Baseball Elbow Injuries: Ambiguity in Scientific Models, Approach, and Execution is Hurting Overhead Athlete Health

Elbow injuries are a significant and increasing issue in baseball. Elbow injuries account for 16% of all injuries sustained at the professional level and collegiate level. Because of the continued rise in injury rates, loss of performance value, and medical burden, sports medicine clinicians have attempted to research the causes underlying this injury epidemic in an attempt to help mitigate baseball elbow injuries. Shoulder range of motion (ROM) is the most researched clinical metric related to elbow injuries in baseball and has the greatest consensus as a viable prognostic factor specifically for medial elbow injury. Shoulder ROM is easy to measure, can be modified through stretching and manual therapy interventions, and can be easily assessed during preseason screening throughout all baseball levels. Despite a large number of studies and the widespread use of shoulder ROM in injury risk screening, current findings are unclear as to whether there is a true cause-effect relation with baseball elbow injuries. We argue that the conflicting findings revolving around the value of shoulder ROM measurements associated with baseball elbow injuries are the result of 4 gaps in the research approaches implemented to date: ambiguous research questions, mixed study populations, statistical models used, and shoulder ROM methodology. Specifically, there is a mismatch of methods, statistical models, and conclusions such as (1) investigating the association (i.e., correlation) between shoulder ROM measurements and injury and (2) investigating the cause-effect relation of shoulder ROM to baseball injuries. The purpose of this article is to detail the required scientific steps to evaluate whether preseason shoulder ROM is a potential causal factor for pitching elbow injury. We also provide recommendations to allow for future causal inferences to be made between shoulder ROM and elbow injury. This information will ultimately assist in informing clinical models of care and decision making for baseball throwers.

The 50 most impactful articles on the medial ulnar collateral ligament: An altmetric analysis of online media

The purpose of this study was to use the Altmetric Attention Score to determine the 50 most impactful medial ulnar collateral ligament articles in online media and compare their characteristics to the most-cited medial ulnar collateral ligament articles in the scientific literature. The Altmetric database was queried to identify all published articles about the medial ulnar collateral ligament, and this list was stratified by the Altmetric Attention Score to identify the 50 highest scoring articles. Several data elements were extracted, including article topic, article type, journal name, and the number of online mentions on Facebook, Twitter, news, and other platforms. Each article's geographic origin was determined based on the institutional affiliation of the first author. Our index search yielded 1283 articles published between 1987 and 2020, from which the 50 articles with the highest Altmetric Attention Scores were included for analysis. Altmetric Attention Scores of the top 50 medial ulnar collateral ligament articles ranged from 20 to 482 (median: 32, interquartile range: 20-62). The most common article type was original research (72%), and the most common topic was epidemiology/risk factors (26%). A majority of studies were Level 3 (36%) or Level 4 evidence (36%). Of the top 50 medial ulnar collateral ligament articles, 94% originated from the United States. A few articles had a high Altmetric Attention Score, suggesting that medial ulnar collateral ligament research does not generate consistently high online attention. The lack of Level 1 studies suggests the need for high-level studies on the medial ulnar collateral ligament. Most studies originated in the United States and were published in the American Orthopaedic Society for Sports Medicine-affiliated journals. The medial ulnar collateral ligament articles included in this study differed substantially from a previous report of the most-cited medial ulnar collateral ligament articles in the literature, suggesting that alternative metrics add a unique dimension to understanding the overall impact of published research on the medial ulnar collateral ligament.

Increasing rates of ulnar collateral ligament repair outpace reconstruction in isolated injuries: review of a Texas surgical database

Background

The gold standard of treatment for ulnar collateral ligament (UCL) injuries has been reconstruction. Despite early repair studies yielding less than satisfactory results, there has been recent renewed interest in UCL repair due to improved outcomes and new technologies. Data regarding clinical use of these procedures are lacking. The purpose of this study was to define the epidemiological trends of UCL repair and reconstruction surgery from 2010 to 2019, compare demographic characteristics of patients undergoing either procedure, and determine incidence of concomitant procedures in each surgical group as well as comparing respective patient-level charges.

Methods

A retrospective database analysis of UCL surgeries was performed through the Texas Healthcare Information Collection database, a comprehensive and publicly available statewide billing dataset. Inclusion criteria were defined using Current Procedural Terminology billing codes for elbow UCL repair and reconstruction between 2010 through 2019, excluding patients who had concomitant elbow fractures or lateral collateral ligament tears indicative of high-energy trauma. Procedural volume changes, patient demographics, and commonly performed concomitant procedures including elbow arthroscopy, ulnar nerve surgery, and platelet-rich plasma injection were compared. Total patient-level charges were compared across groups.

Results

A total of 1664 patients were included, consisting of 484 UCL repairs and 1180 reconstructions. Total UCL surgeries increased eleven-fold when corrected for population growth from 2010 (N = 25) to 2019 (N = 315). In 2010, repair constituted 23% of all UCL tear surgeries and increased to 40% by the end of 2019. The annual frequency of UCL repair increased at a 5.4% faster rate than UCL reconstruction from 2010 to 2019 (P < .001). There were no significant differences between any demographic data between UCL repair and reconstruction except for rural surgical settings which demonstrated 1.8 times greater odds of undergoing reconstruction (P = .05). There were no differences among commonly associated procedures including ulnar nerve surgery (P = .217), elbow arthroscopy (P = .092), and platelet-rich plasma injection (P = .837) with no differences in patient-level charges at any time point (P = .47).

Conclusion

While reconstruction remains more common, the annual frequency of UCL repair is increasing at a faster rate. Since were no demographic differences aside from surgical setting, it can be inferred that patients who were previously receiving reconstruction are instead undergoing repair. This highlights the need for future studies to further identify surgical indications for the two interventions.

Pain Is the Most Frequently Cited Reason Athletes Fail to Return to Sport After Ulnar Collateral Ligament Surgery: A Systematic Review and Meta-analysis

Background

No previous systematic review to our knowledge has examined the reasons that athletes fail to return to sport (RTS) after ulnar collateral ligament (UCL) surgery.

Purpose

To report the rate of failure to RTS after UCL surgery and identify reasons that preclude an athlete's ability to successfully RTS.

Study Design

Systematic review; Level of evidence, 4.

Methods

This study was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We searched the PubMed, Scopus, and SPORTDiscus databases for studies on athletes who underwent either UCL reconstruction or repair that reported RTS rates and identified reasons for failure to RTS. Data were collected on the number of athletes included, average age, sport played, operative technique, average follow-up, rate of failure to RTS, and reasons for failure to return. A random-effects model was used to conduct the meta-analysis.

Results

Included were 26 studies reporting on 1019 athletes. Primary or revision UCL reconstruction was performed in 913 patients (89.6%), while the remaining 106 patients (10.4%) underwent UCL repair. The pooled rate of failure to RTS after UCL reconstruction or repair was calculated to be 11.4% (95% CI, 8.4-14.7). A significantly higher estimated proportion of athletes failed to return because of elbow-related reasons compared with non-elbow-related reasons (55.3% vs 40.6%; P = .0352). Persistent pain (29/103; 28.2%) was the most common reason for failure to return, followed by elbow limitations and other unspecified elbow problems (19/103; 18.4%). There was moderate evidence for publication bias and study heterogeneity across the included studies.

Conclusion

This meta-analysis estimated the rate of failure to RTS after UCL surgery as 11.4%, with the majority of athletes unable to return because of elbow pain. Future studies reporting outcomes and providing details as to why athletes are unable to RTS can better inform sport surgeons on factors precluding RTS and can guide clinical practice to better help athletes achieve their postoperative goals.

Rehabilitation and Return to Sport Criteria Following Ulnar Collateral Ligament Reconstruction: A Systematic Review

BACKGROUND

Ulnar collateral ligament (UCL) reconstruction (UCLR) is a viable treatment option for patients with UCL insufficiency, especially in the overhead throwing athlete. Within the clinical literature, there is still no universally agreed upon optimal rehabilitation protocol and timing for return to sport (RTS) after UCLR.

HYPOTHESIS

There will be significant heterogeneity with respect to RTS criteria after UCLR. Most surgeons will utilize time-based criteria rather than functional or performance-based criteria for RTS after UCLR.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

All level 1 to 4 studies that evaluated UCLR with a minimum 1-year follow-up were eligible for inclusion. Studies lacking explicit RTS criteria, studies that treated UCL injury nonoperatively or by UCL repair, or studies reporting revision UCLR were excluded. Each study was analyzed for methodologic quality, RTS, timeline of RTS, and RTS rate.

RESULTS

Overall, 1346 studies were identified, 33 of which met the inclusion criteria. These included 3480 athletes across 21 different sports. All studies reported RTS rates either as overall rates or via the Conway-Jobe scale. Timelines for RTS ranged from 6.5 to 16 months. Early bracing with progressive range of motion (ROM) (93.9%), strengthening (84.8%), and participation in an interval throwing program (81.8%) were the most common parameters emphasized in these rehabilitation protocols. While all studies included at least 1 of 3 metrics for the RTS value assessment, most commonly postoperative rehabilitation (96.97%) and set timing after surgery (96.97%), no article completely defined RTS criteria after UCLR.

CONCLUSION

Overall, 93.9% of studies report utilizing bracing with progressive ROM, 84.8% reported strengthening, and 81.8% reported participation in an interval throwing program as rehabilitation parameters after UCLR. In addition, 96.97% reported timing after surgery as a criterion for RTS; however, there is a wide variability within the literature on the recommended time from surgery to return to activity. Future research should focus on developing a comprehensive checklist of functional and performance-based criteria for safe RTS after UCLR.

Return to performance following severe ankle, knee, and hip injuries in National Basketball Association players

The purpose of this study was to compare basketball performance markers 1 y prior to initial severe lower extremity injury, including ankle, knee, and hip injuries, to 1 and 2 y following injury during the regular National Basketball Association (NBA) season. Publicly available data were extracted through a reproducible extraction computed programmed process. Eligible participants were NBA players with at least three seasons played between 2008 and 2019, with a time-loss injury reported during the study period. Basketball performance was evaluated for season minutes, points, and rebounds. Prevalence of return to performance and linear regressions were calculated. A total of 285 athletes sustained a severe lower extremity injury. A total of 196 (69%) played for 1 y and 130 (45%) played for 2 y following the injury. A total of 58 (30%) players participated in a similar number of games and 57 (29%) scored similar points 1 y following injury. A total of 48 (37%) participated in a similar number of games and 55 (42%) scored a similar number of points 2 y following injury. Fewer than half of basketball players who suffered a severe lower extremity injury were participating at the NBA level 2 y following injury, with similar findings for groin/hip/thigh, knee, and ankle injuries. Fewer than half of players were performing at previous preinjury levels 2 y following injury. Suffering a severe lower extremity injury may be a prognostic factor that can assist sports medicine professionals to educate and set performance expectations for NBA players.

Initial kinematic chain injuries increase hazard of subsequent arm injuries in professional baseball pitchers

BACKGROUND

Currently, there are few studies that have evaluated the relationship between a lower extremity or trunk injury (kinematic chain) and subsequent arm injury. The purpose of this study was (1) to investigate the relationship between initial kinematic chain (lower extremity or trunk) injury and subsequent arm injury; and (2) to investigate the relationship between initial shoulder or elbow injury and subsequent arm injury.

METHODS

A 7-year prospective injury risk study was conducted with Minor League Baseball pitchers. Pitches, pitching appearances, athlete exposures (AEs), and arm injuries (≥1-day time loss) were documented throughout the season. Cox survival analyses with 95% confidence intervals (95% CIs) were performed. Confounders controlled for included age, body mass index, arm dominance, pitching role, previous arm injury, number of pitching appearances, and seasonal pitch load.

RESULTS

A total of 297 pitchers participated (total player days = 85,270). Arm injury incidence was 11.4 arm injuries/10,000 AEs, and kinematic chain incidence was 5.2 injuries/10,000 AEs. Pitchers who sustained a kinematic chain injury demonstrated a greater hazard (2.6 [95% CI: 1.2, 5.6], P = .019) of sustaining an arm injury. Pitchers who sustained an initial shoulder injury demonstrated a greater hazard (9.3 [95% CI: 1.1, 83], P = .047) of sustaining a subsequent shoulder or elbow injury compared with pitchers who sustained an initial elbow injury.

CONCLUSIONS

Pitchers who sustained an initial lower extremity or trunk injury demonstrated an increased subsequent arm injury hazard compared with pitchers who did not. Pitchers who sustained an initial shoulder injury demonstrated a greater hazard of sustaining a subsequent arm injury compared with pitchers who sustained an initial elbow injury. However, this secondary analysis should be interpreted with caution. Clinicians should monitor risk with workload accumulation, which may be related to pitching compensatory strategies in a fatigued state. Pitchers who sustain a shoulder injury should be evaluated and perform both shoulder and elbow rehabilitation strategies before return to sport.

Return-to-Competition Criteria After Ulnar Collateral Ligament Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

Injury to the ulnar collateral ligament of the elbow is common among overhead throwing athletes and can result in significant functional limitations. While surgical reconstruction offers high rates of return to competition, there are no validated or universally accepted guidelines for determining when an athlete can safely resume play.

PURPOSE

To assess the existing scientific literature for return-to-competition criteria utilized after ulnar collateral ligament reconstruction.

STUDY DESIGN

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

METHODS

The PubMed database was searched for clinical investigations of ulnar collateral ligament reconstruction in overhead throwing athletes published between January 2000 and June 2020. Only studies that had a minimum follow-up of 1 year and included at least 1 specific return-to-competition criterion were considered.

RESULTS

A total of 15 studies were included in the final analysis, encompassing 1156 patients with an average age of 20.7 years (SD, 2.0 years). Baseball players composed 96.3% of patients for whom sport was specified, and 92.4% of baseball players were pitchers. The most common return-to-competition criterion, identified in 87% of studies, was completion of a return-to-throwing program, which started on average 16.7 weeks (range, 12-18 weeks) after surgery. A return-to-mound program was utilized in 53% of studies, starting on average 7.4 months (range, 6-9 months) postoperatively. Minimum time from surgery was used in 73% studies, with players waiting 7 to 12 months (mean, 9.7; SD, 1.4 months) after surgery before return-to-competition consideration. The overall rate of return to competition at the preinjury level or higher was 85.7% (SD, 8.5%) at an average of 12.2 months (SD, 0.6 months).

CONCLUSION

In general, we observed a paucity of literature describing the return-to-competition process after ulnar collateral ligament reconstruction in overhead throwing athletes. Only 3 explicit return-to-competition criteria were identified across all studies: completion of a return-to-throwing program, completion of a return-to-mound program for pitchers, and minimum time from surgery. Increased transparency regarding postoperative rehabilitation protocols and further research are necessary to identify and validate sport-specific return-to-competition criteria, which will ultimately help athletes return to play in a safe and timely fashion after ulnar collateral ligament reconstruction.

Trends in Medial Ulnar Collateral Ligament Repair and Reconstruction From 2007 to 2016: A Population-Based Study of a Large Private Insurance Database

Background: Ulnar collateral ligament (UCL) reconstruction and UCL repair of the elbow are commonly performed procedures, resulting in high return-to-play rates. Whether the incidence rate of UCL reconstruction vs UCL repair has changed over time is not currently known. Purpose/Questions: We sought to assess temporal trends in the incidence rates of UCL repair and UCL reconstruction and to identify factors associated with UCL reconstruction. We hypothesized that UCL repair would demonstrate an increased incidence overall in recent years with an associated decline in UCL reconstruction rates. Methods: Using the PearlDiver Research Program to query the Humana administrative claims database, we identified patients who had undergone UCL repair and/or reconstruction from 2007 to 2016. Patients were stratified by age (15-19; 20-29; 30-49 years), sex, and year (2007-2011 vs 2012-2016). Poisson regression analysis (continuous variables) was used to calculate the incidence risk ratio (IRR); chi-square tests were performed for categorical variables, and odds ratios were calculated with 95% confidence intervals (CI). Results: The incidence rate of UCL repair was greater in 2012-2016 than in 2007-2011 (IRR: 1.86, 95% CI: 1.16-2.96). The incidence rate of UCL reconstruction vs UCL repair was greater for patients aged 15 to 19 years (IRR: 3.37, 95% CI: 1.97-5.77) but not patients aged 20 to 29 years (IRR: 0.89, 95% CI: 0.49-1.59) as compared with patients aged 30 to 49. Males aged 19 years were more likely than females to undergo UCL reconstruction (IRR: 10.09, 95% CI: 1.37-3.45). Conclusion: While UCL procedures are becoming more popular, our retrospective analysis showed that young males are preferentially treated with UCL reconstruction, warranting further investigation into these trends.

Effect of COVID-19 on Ulnar Collateral Ligament Reconstruction in Major League Baseball Pitchers

Background:

The coronavirus disease of 2019 (COVID-19) pandemic led to the suspension and shortening of the 2020 Major League Baseball (MLB) season from 162 to 60 regular season games. The effect of this disruption on injury rates, specifically injury to the ulnar collateral ligament (UCL), has not been quantified.

Purpose/Hypothesis:

The purpose of this study was to compare the rate of UCL reconstruction (UCLR), surgery timing, and pitching workload in MLB pitchers from before and after the COVID-19 pandemic lockdown. We hypothesized that UCLR rates relative to games played would be increased and pitching workload would be decreased in 2020 compared with previous seasons.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

An extensive online search using publicly available data was conducted to identify all MLB pitchers who underwent UCLR between January 1, 2017, and December 31, 2020. Only pitchers who were competing at the MLB level when undergoing reconstruction were included. Player characteristics and surgery date, as well as career and season of surgery pitching workload, were collected for all included pitchers. All data were compared as a pooled sample (2017-2019 vs 2020).

Results:

A similar number of pitchers underwent UCLR during or after the 2020 regular season (n = 18) compared with the 2017-2019 seasons (n = 16, 20, and 16, respectively). However, after accounting for the decrease in games played during the 2020 regular season, an MLB pitcher was 2.9 times more likely to undergo surgery per game after the COVID-19 lockdown compared with the previous years (P < .001). MLB pitchers who underwent surgery in 2020 threw fewer preseason innings than did pitchers who underwent surgery between 2017 and 2019 (5.98 vs 9.39; P = .001).

Conclusion:

MLB pitchers were almost 3 times more likely to undergo UCLR per game after the COVID-19 lockdown. A decreased preseason pitching workload because of the COVID-19 lockdown may have had an effect on per game UCLR rates.

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.

Ulnar collateral ligament reconstruction of the elbow at minimum 48-month mean follow-up demonstrates excellent clinical outcomes with low complication and revision rates: systematic review

IMPORTANCE

Tears of the ulnar collateral ligament (UCL) of the elbow occur predominantly as an overuse injury, most commonly affecting throwing athletes, particularly baseball players. UCL reconstruction (UCLR) has been described as an effective treatment modality in the short term.

OBJECTIVE

The purpose of this study was to systematically review the evidence in the literature to ascertain the clinical outcomes, complication and revision rates in baseball players following UCLR of the elbow at a minimum of 48 months of follow-up.

EVIDENCE REVIEW

Two independent reviewers performed a search of the literature based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the EMBASE, PubMed and Scopus databases. Clinical studies were included if they reported outcomes of baseball players at a minimum of 48 months following UCLR.

FINDINGS

Our review included 8 studies including 1104 baseball players (1105 elbows) at mean 69.9 months (48-205) following UCLR. The majority of baseball players were pitchers (92.3%), with a mean age of 22.2 years (13-42). At final follow-up, the overall return to play (RTP) was 95.3%%, with 85.3% returning at pre-injury level. In addition, the mean reported Conway-Jobe score was 86.8%, the revision rate was 6.0% with postoperative neuropathy reported in 2.4% of patients. A total of 479 (43.4%) were professional baseball players, with an overall RTP rate of 97.5% and 82.3% managing to RTP at their pre-injury level. The mean number of career years following UCLR was 4.7 years (0-22).

CONCLUSION AND RELEVANCE

UCLR provides excellent patient-reported and clinical outcomes to patients at medium-term follow-up with low complication and revision rates. In addition, high rates of RTP at pre-injury level and career longevity were reported by baseball players following UCLR.

LEVEL OF EVIDENCE

Level IV; Systematic Review.

Rehabilitation Following Ulnar Collateral Ligament Reconstruction in Overhead-Throwing Athletes

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The prevalence of ulnar collateral ligament (UCL) injury and UCL reconstruction (UCL-R) continues to rise, causing morbidity in overhead-throwing athletes.

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Postoperative rehabilitation protocols are essential for proper healing of the reconstructed ligament and safely returning athletes to competition, yet there is no uniformly accepted standard of care.

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UCL-R rehabilitation has traditionally been guided by expert opinion and conventional wisdom rather than scientific studies, resulting in substantial variability in rehabilitation practices, time to return to play, and outcomes.

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Current research efforts aim to closely investigate the biomechanical implications of UCL-R and overhead throwing to better guide rehabilitation and to improve competitive performance and outcomes.

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Additional biomechanical and scientific studies on rehabilitation modalities and timing are warranted for systematic analysis, optimization, and standardization of UCL-R rehabilitation.

The Effect of the Crow Hop on Elbow Stress During an Interval Throwing Program

BACKGROUND

Postoperative rehabilitation protocols after ulnar collateral ligament (UCL) reconstruction typically involve a structured interval throwing program. In an effort to minimize torque placed on the UCL, athletes are often instructed to throw with a crow hop, even at short throwing distances. However, the effect of the crow hop on medial elbow stress is unknown.

PURPOSE/HYPOTHESIS

The purpose was to determine whether elbow stress differs with and without a crow hop across the throwing distances of a typical interval throwing program. We hypothesized that crow hop throws would generate lower torque on the elbow than standing throws at each distance of the interval throwing program.

STUDY DESIGN

Controlled laboratory study.

METHODS

Healthy high school and collegiate pitchers and position players were recruited from the surrounding area. Each player was outfitted with a wearable athletic sleeve and device that recorded elbow torque (Newton-meters), arm slot (degrees), arm speed (revolutions per minute), and shoulder rotation (degrees). Ball velocity (miles per hour) was measured using a radar gun. Players were instructed to perform 3 crow hop throws and 3 standing throws at distances of 30, 45, 60, 90, 120, 150, and 180 feet. A repeated measures analysis of variance was used to compare ball velocity, elbow torque, arm slot, arm speed, and shoulder rotation between crow hop and standing throws at each throwing distance.

RESULTS

Twenty athletes participated in this study (average age, 17.8 years; range, 15-25 years). The average medial elbow torque increased at each distance for both crow hop and standing throws at distances of 30, 45, 60, and 90 feet (P < .05), after which there were no significant increases in elbow torque (P > .05). The average torque was higher for crow hop throws than standing throws at distances of 30 feet (13.9 N·m vs 12.0 N·m; P = .002), 45 feet (21.8 N·m vs 19.3 N·m; P = .005), and 60 feet (28.0 N·m vs 24.5 N·m; P = .02).

CONCLUSION

Crow hop throws generated greater medial elbow torque than standing throws at distances up to 60 feet; however, there were no differences in elbow torque at distances greater than 60 feet between the 2 throw types. For both crow hop and standing throws, elbow stress increased at each distance interval up to 90 feet before plateauing at distances greater than 90 feet. The crow hop throwing technique does not reduce medial elbow stress during a simulated interval throwing program, and it may actually increase torque at shorter throwing distances.

CLINICAL RELEVANCE

The results of our study indicate that it would be prudent for players to initially perform standing throws at shorter distances and only later be allowed to employ a natural crow hop at greater distances to minimize torque placed on the medial elbow during UCL rehabilitation protocols.

Return-to-Play and Competitive Outcomes After Ulnar Collateral Ligament Reconstruction Among Baseball Players: A Systematic Review

Background:

Ulnar collateral ligament (UCL) reconstruction (UCLR) is very common in baseball. However, no review has compared the return-to-play (RTP) and in-game performance statistics of pitchers after primary and revision UCLR as well as of position players after UCLR.

Purpose:

To review, synthesize, and evaluate the published literature on outcomes after UCLR in baseball players to determine RTP and competitive outcomes among various populations of baseball players.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A literature search including studies between 1980 and November 4, 2019, was conducted for articles that included the following terms: ulnar collateral ligament, elbow, medial collateral ligament, Tommy John surgery, throwing athletes, baseball pitchers, biomechanics, and performance. To be included, studies must have evaluated baseball players at any level who underwent UCLR (primary or revision) and assessed RTP and/or competitive outcomes.

Results:

A total of 29 studies with relatively high methodological quality met the inclusion criteria. After primary UCLR, Major League Baseball (MLB) pitchers returned to play in 80% to 97% of cases in approximately 12 months; however, return to the same level of play (RTSP) was less frequent and took longer, with 67% to 87% of MLB pitchers returning in about 15 months. RTP rates for MLB pitchers after revision UCLR were slightly lower, ranging from 77% to 85%, while RTSP rates ranged from 55% to 78%. RTP rates for catchers (59%-80%) were generally lower than RTP rates for infielders (76%) and outfielders (89%). All studies found a decrease in pitching workloads after UCLR. Fastball usage may also decrease after UCLR. Changes in earned run average and walks plus hits per inning pitched were inconclusive.

Conclusion:

Pitchers returned to play after UCLR in approximately 12 months and generally took longer to return to their same level of play. Pitchers also returned to play less frequently after revision UCLR. After both primary and revision UCLR, professional pitchers experienced decreased workloads and potentially decreased fastball usage as well. Catchers may RTP after UCLR less frequently than pitchers, infielders, and outfielders possibly because of the frequency of throwing in the position. These results will help guide clinical decision making and patient education when treating UCL tears in baseball players.

Treatment of elbow instability: state of the art

The elbow is a congruent joint with a high degree of inherent stability, provided by osseous and soft-tissue constraints; however, when substantial lesions of these stabilising structures happen, instability of the elbow occurs. Significant improvements in surgical elbow instability diagnosis and treatment have been recently introduced both for acute and chronic cases. Specific stress tests, recently introduced in the clinical practice, and different imaging techniques, both static and dynamic, allow assessment of the elbow stabilisers and detection of the instability direction and mechanism even in subtle forms. Many surgical techniques have been standardised and surgical instruments and devices, specifically dedicated to elbow instability treatment, have been developed. Specific rehabilitation protocols have been designed to protect the healing of the elbow stabilisers while minimising elbow stiffness. However, despite the progress, surgical treatments can be challenging even for expert surgeons and the rate of persistent instability, post-traumatic arthritis, stiffness and pain can be still high especially in most demanding cases. The biology of the soft-tissue healing remains one of the most important aspects for future investigation. If future research will help to understand, correct or modulate the biological response of soft-tissue healing, our confidence in elbow instability management and the reproducibility of our treatment will tremendously improve. In this paper, the state of the art of the current knowledge of elbow instability is presented, specifically focusing on modern surgical techniques used to solve instability, with repair or reconstruction of the damaged elbow stabilisers.

THE SUCCESS OF RETURN TO SPORT AFTER SUPERIOR LABRUM ANTERIOR TO POSTERIOR (SLAP) TEARS: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Reviews on superior labral anterior to posterior (SLAP) injuries have been reported in the literature. However, current reviews have not focused on the success of athletes return to their previous level of sport or athletic performance.

Hypothesis/Purpose

Systematically review return to sport (RTS) and return to sport at previous level (RTSP) proportions after SLAP injury while reporting any additional performance metrics and outcome measures.

Study Design

Systematic Review & Meta-Analysis.

Methods

A computer assisted literature search of MEDLINE, CINAHL, Embase and SportDiscus databases utilizing keywords related to RTS post-surgery for SLAP tear was implemented. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were utilized for study methodology. Quality assessment utilized the MINORS scale.

Results

Twenty-two studies (617 athletes) qualified for analysis. Based on limited evidence from level 3b to 4 studies, athletes RTS post intervention for SLAP injury occurred at a rate of 93% (95% CI:87 to 98%) and overall RTSP rate was 72% (95% CI:60 to 83%). The mean time to RTS post intervention was reported in 59% of studies at 6.9 ± 2.9 months. Patient reported outcome measures (PROM's) were reported in 86% of studies. There was limited reporting of performance statistics, rehabilitation guidelines, return to sport criteria, and information regarding SLAP diagnosis in the available studies. None of the included studies reported post-surgical athletic performance or career longevity.

Conclusions

Limited evidence suggests that less than three in four athletes return to their previous level of sport participation after SLAP injury intervention. Treatment success for an athlete with SLAP injury remains relatively unknown as only 59% of included studies clearly delineate RTS from RTSP and neither athletic performance nor career longevity were reported in any included studies. Future studies of higher quality are required for this determination.

Level of Evidence

Level 1a.

Functional outcomes of ulnar collateral ligament reconstruction with a novel double suspensory fixation

BACKGROUND

Ulnar collateral ligament reconstruction (UCLR) has allowed the return of overhead athletes to throwing sports. We describe a new double suspensory (DS) technique using a single tunnel in the ulna and humerus, achieving fixation with adjustable loop buttons.

METHODS

Inclusion criteria included skeletally mature baseball players with clinical and magnetic resonance imaging diagnosis of UCL insufficiency who failed a trial of structured nonoperative treatment. A total of 36 baseball players underwent DS UCLR, between 2011 and 2017, by 1 surgeon with minimum 2-year follow-up. The graft was fixated with an adjustable button loop on the humeral side and a tension slide technique with a button on the ulnar side. Pre- and postoperative Kerlan-Jobe Orthopaedic Clinic and Single Assessment Numerical Evaluation and postoperative Conway scores were obtained.

RESULTS

The mean age was 19.8 ± 4.6 years (range, 14-35 years). All were male. Mean years played before surgery was 14.3 ± 4.6 years (range, 8-28 years). There were 32 (89%) pitchers and 4 (11%) position players. There were 13 (36%) high school, 20 (55%) college, 2 (6%) minor league, and 1 (3%) adult league athletes. The mean follow-up was 55.3 ± 23.7 months (range, 26-97 months). There was significant improvement in Kerlan-Jobe Orthopaedic Clinic (33.2 ± 19.9 to 89.7 ± 15.1, P < .0001) and Single Assessment Numerical Evaluation (20.7 ± 16.7 to 93.6 ± 11.9, P < .0001) scores. Using Conway scoring, 25 (69%) had excellent, 5 (14%) good, 3 (8%) fair, and 3 (8%) poor scores. Mean return to play was 9 ± 1.5 months (range, 6-16 months). Only 1 (3%) athlete required a revision surgery and ultimately returned to play and 1 (3%) hardware removal. None developed ulnar nerve symptoms.

CONCLUSION

DS fixation for UCLR in baseball players can lead to excellent clinical results and early return to play.

A qualitative assessment of return to sport following ulnar collateral ligament reconstruction in baseball players

Background

The rate of ulnar collateral ligament (UCL) reconstruction has been increasing at all levels of play. With excellent outcomes, primary UCL reconstruction has allowed many overhead athletes to return to their pre-injury sport. However, the subjective factors influencing this decision to return to sport have yet to be studied. The aim of this study is to understand the factors influencing an athlete's decision to return to pre-injury level of sport after primary UCL reconstruction.

Methods

An experienced interviewer conducted qualitative, semi-structured interviews of patients aged 18-35 years who had undergone primary UCL reconstruction by one fellowship-trained, Major League Baseball (MLB) team orthopaedic surgeon. All subjects were throwing athletes prior to injury and had a minimum two-year follow-up without revisions. Qualitative analysis was then performed to derive codes, categories, and themes. Patients were surveyed to assess familiarity with UCL reconstruction as well as to obtain Kerlan-Jobe Orthopaedic Clinic (KJOC) Overhead Athlete Shoulder and Elbow score, American Shoulder and Elbow Surgeons Shoulder (ASES) score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) highlighting current activity and function levels along with sport participation.

Results

Twenty-two athletes were interviewed to elucidate four predominant themes influencing their return to sport: trust in surgeon and care team, innate drive and optimism, misconceptions regarding post-operative athletic ability, and life priorities. A significant difference was noted between patients that returned and those that did not in the KJOC survey and for the statement that UCL reconstruction surgery would improve throwing ability relative to patients' peak performance three years prior to the surgery. Athletes who did not return to sport cited lifestyle changes and age as limiting factors.

Conclusion

Patients' decision to return to their pre-injury level of sport after primary UCL reconstruction was based on trust in their care team's reputation, intrinsic personality traits, anecdotal evidence about post-operative outcomes, and lifestyle. This study emphasizes the importance for health care providers to educate patients toward realistic expectations upon return to sport. On a larger scale, this study illustrates the effects the media and anecdotal experiences of a growing population of players undergoing UCL reconstruction have had on the game of baseball and players' decisions to return to sport.

Level of evidence

Level IV.

The Relationship Between Baseball Participation and Health: A Systematic Scoping Review

OBJECTIVE

To investigate the relationship between baseball participation and health (musculoskeletal, general, and psychological health) and to identify research gaps in the existing literature.

DESIGN

Systematic scoping review.

LITERATURE SEARCH

Medical databases and gray literature were systematically searched from inception to November 2018.

STUDY SELECTION CRITERIA

All studies that investigated constructs related to the health of current or former baseball players were included.

DATA SYNTHESIS

Data were extracted for thematic summaries.

RESULTS

Ten thousand five hundred seventy-four titles/abstracts were screened, and 678 studies were included. Ninety percent of articles included only baseball players playing in the United States, 34% of articles investigated professional baseball players, and 11% studied college baseball players. Five hundred eighty-three (86%) studies investigated musculoskeletal health, 77 (11%) general health, and 18 (3%) psychological health. Injury incidence (injuries per 1000 athlete exposures) ranged from 0.7 to 3.6 in professional, 4.7 to 5.8 in college, and 0.8 to 4.0 in high school baseball. Among baseball players, 31% to 50% reported regular tobacco use. There was limited research investigating psychological health in current or former baseball players at all competition levels.

CONCLUSION

Almost 90% of all articles investigated musculoskeletal health, with few articles studying general or psychological health. Baseball players have high tobacco, alcohol, and drug use compared to the general population, which may have negative health outcomes. Little is understood about the long-term musculoskeletal, general, and psychological health of baseball players. J Orthop Sports Phys Ther 2020;50(2):55-66. doi:10.2519/jospt.2020.9281.

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.

Nonoperative Treatment of Elbow Ulnar Collateral Ligament Injuries With and Without Platelet-Rich Plasma in Professional Baseball Players: A Comparative and Matched Cohort Analysis

BACKGROUND

Recent studies evaluating nonoperative treatment of elbow ulnar collateral ligament (UCL) injuries augmented with platelet-rich plasma (PRP) have shown promising results. To date, no comparative studies have been performed on professional baseball players who have undergone nonoperative treatment with or without PRP injections for UCL injuries.

HYPOTHESIS

Players who received PRP injections would have better outcomes than those who did not receive PRP.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The Major League Baseball (MLB) Health and Injury Tracking System identified 544 professional baseball players who were treated nonoperatively for elbow UCL injuries between 2011 and 2015. Of these, 133 received PRP injections (PRP group) before starting their nonoperative treatment program, and 411 did not (no-PRP group). Player outcomes and a Kaplan-Meier survival analysis were compared between groups. In addition, to reduce selection bias, a 1:1 matched comparison of the PRP group versus the no-PRP group was performed. Players were matched by age, position, throwing side, and league status: major (MLB) and minor (Minor League Baseball [MiLB]). A single radiologist with extensive experience in magnetic resonance imaging (MRI) interpretation of elbow injuries in elite athletes analyzed 243 MRI scans for which images were accessible for tear location and grade interpretation.

RESULTS

Nonoperative treatment of UCL injuries resulted in an overall 54% rate of return to play (RTP). Players who received PRP had a significantly longer delay in return to throwing (P < .001) and RTP (P = .012). The matched cohort analysis showed that MLB and MiLB pitchers in the no-PRP group had a significantly faster return to throwing (P < .05) and the MiLB pitchers in the no-PRP group had a significantly faster RTP (P = .045). The survival analysis did not reveal significant differences between groups over time. The use of PRP, MRI grade, and tear location were not statistically significant predictors for RTP or progression to surgery.

CONCLUSION

In this retrospective matched comparison of MLB and MiLB pitchers and position players treated nonoperatively for a UCL tear, PRP did not improve RTP outcomes or ligament survivorship, although there was variability with respect to PRP preparations, injection protocols, time from injury to injection, and rehabilitation programs. MRI grade and tear location also did not significantly affect RTP outcomes or progression to surgery.

Outcomes With a Focus on Return to Play for Revision Ulnar Collateral Ligament Surgery Among Elite-Level Baseball Players: A Systematic Review

BACKGROUND

Ulnar collateral ligament (UCL) reconstruction is commonly performed among overhead throwing athletes. Previous studies demonstrated relatively high rates of return to sport after primary reconstruction. Outcomes after revision UCL reconstruction have not been widely studied.

PURPOSE

To report the rate of return to sport after revision UCL reconstruction among elite-level baseball players.

STUDY DESIGN

Systematic review.

METHODS

A systematic review of the literature following the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines was performed for high-level baseball players undergoing revision UCL reconstruction. Study bias was assessed with the Methodological Index for Non-Randomized Studies scoring system. The primary outcome measure was whether the study participants were able to return to sport after revision UCL reconstruction. Secondary outcome measures included career length after revision and pitching performance statistics. Data were summarized with ranges, tables, and weighted averages. A subjective analysis was performed.

RESULTS

A total of 5 studies met inclusion criteria. The rate of return to sport at preinjury level was 62.8%. Among Major League Baseball pitchers, the rate of return to sport at the preinjury level was 68.8%. The rate of return to sport at the same level or lower (Major League Baseball, minor league, collegiate) was 78.1%. Time to return to sport ranged from 1.3 to 1.7 years. Mean earned run average after revision ranged from 4.87 to 5.04. Mean number of innings pitched per season after revision ranged from 36.95 to 50.5.

CONCLUSION

This systematic review demonstrated a limited rate of return to preinjury level of sport among elite-level baseball players who underwent revision UCL reconstruction. Pitching durability and career longevity were inferior to results that were reported for players who underwent primary UCL reconstruction alone. This study suggests that outcomes after revision UCL reconstruction are not reliable and elite-level players should be counseled accordingly.

Correlation of Force to Deformation of the Anterior Bundle of the Medial Collateral Ligament Through Consideration of Band Laxity

The anterior bundle of the medial collateral ligament (AMCL) resists the loads that arise at the elbow during overhand throwing and has commonly been divided into posterior and anterior bands. While these anterior and posterior bands have been thought to bear the load at different flexion angles, any transition of the load distribution between the two bands is poorly understood and has not considered laxity (slack). This study considers the AMCL as three bands and quantifies the mechanical response to vertical distraction, simulating valgus-load joint opening, through the sequential superposition of the band responses after the elimination of inherent laxity. Eight cadaveric elbow specimens were used for the study. The intact AMCL of each specimen was tested under vertical distraction in a specialized load frame at four elbow flexion angles and then subsequently retested after two longitudinal transections. The greatest laxity at full extension and full flexion belonged to the posterior (1.9 mm) and anterior (2.4 mm) band, respectively. At the lesser and higher flexion angles, the greatest structural stiffness belonged to the anterior and middle band. The overall AMCL was the most structurally stiff at 60°, with approximately 150 N of force required for 2% elongation. This study shows that the different bands of the AMCL may have different load bearing properties at different flexion angles, causing each band to support different proportions of an imposed load. The presence of the laxity may impose a load-bearing delay, causing load-bearing in each band to begin asynchronously. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2027-2034, 2019.

The pathoanatomy of the anterior bundle of the medial ulnar collateral ligament

BACKGROUND

The purpose of this study was to increase our understanding of the pathoanatomy of the ulnar collateral ligament (UCL) by performing a descriptive analysis of the surgical inspection of the anterior bundle in patients undergoing reconstruction.

METHODS

A single-surgeon series of 163 patients who underwent UCL reconstruction between 2009 and 2017 was retrospectively analyzed. Descriptions of the pathoanatomy of injury were obtained from the operative reports. Magnetic resonance imaging data were reviewed to assess whether the presence and location of tissue disruptions were accurately recognized. Demographic and clinical characteristics were obtained from medical records and correlated to observed pathoanatomy.

RESULTS

Injuries to the anterior bundle were characterized by a single tissue disruption (65%), tissue disruptions at more than 1 location (23%), or injuries without distinct fiber tissue disruptions (12%). The presence and location of tissue disruptions matched magnetic resonance imaging findings in 124 of 153 patients (81%). Partial tears more frequently affected the anterior band of the anterior bundle distally as opposed to the posterior band of the anterior bundle proximally (P = .012). Patients with single tissue disruptions more frequently reported a popping sensation than patients with non-tear insufficiency (P = .030).

CONCLUSIONS

This study shows the heterogeneity of anterior bundle injuries in patients undergoing UCL reconstruction. A variety of injury configurations and chronic attritional damage to the anterior bundle were observed, as well as distinct tear patterns at the distal and proximal attachment sites. Future research may elucidate the diagnostic value of a pop sign for UCL injury.

Return to Play and In-Game Performance Statistics Among Pitchers After Ulnar Collateral Ligament Reconstruction of the Elbow: A Systematic Review

BACKGROUND

Injury to the ulnar collateral ligament of the elbow is relatively common among baseball pitchers. Ulnar collateral ligament reconstruction (UCLR) has revolutionized the management of this injury, allowing a greater proportion of pitchers to return to play.

PURPOSE

To assess the return to play and in-game performance specific to baseball pitchers who have undergone primary UCLR.

STUDY DESIGN

Systematic review.

METHODS

This review was conducted according to the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The electronic databases MEDLINE, EMBASE, and PubMed were searched for relevant studies, and pertinent data were abstracted. Only studies reporting in-game performance statistics (earned run average [ERA], pitching velocity, innings pitched per season, etc) of pitchers after UCLR were included. The methodological index for nonrandomized studies (MINORS) was used to assess study quality.

RESULTS

A total of 14 studies and 1520 pitchers were included in this systematic review. All studies were of level 3 or 4 evidence, and the mean ± SD MINORS score was 14.4 ± 3.0, which indicates fair quality of evidence for nonrandomized studies. The rates of return to any level of pitching after UCLR ranged from 79% to 100%. Subgroup analysis revealed that 79% to 87% of Major League Baseball (MLB) pitchers returned to preinjury levels of pitching. The mean time to return to play was 19.8 ± 13.5 months, and the mean time to return to competition for MLB pitchers was 17.3 ± 2.4 months. Of the 5 studies reporting ERA, 2 cited a significant increase after UCLR, and 1 indicated a significant decrease. Of the 4 studies reporting fastball velocity, 3 cited decreased pitching velocities after UCLR. All studies found that pitchers pitched, on average, fewer innings per game or season after UCLR.

CONCLUSION

There was a high rate of return to pitching after UCLR. However, most studies showed that UCLR was associated with a prolonged recovery and significant decline in pitching performance as objectively measured by in-game statistics. The strength of these conclusions is limited by the quality of the available literature and inconsistencies in the reporting of outcomes.

Considerations of Conservative Treatment After a Partial Ulnar Collateral Ligament Injury in Overhead Athletes: A Systematic Review

CONTEXT

Ulnar collateral ligament (UCL) reconstructions continue to increase without consensus on an evidence-based treatment protocol for nonoperative management. Currently, there is no consensus on an effective nonoperative protocol for partial UCL injuries that uses return-to-play (RTP) rates in determining the outcome of conservative treatment.

OBJECTIVE

To systematically review RTP rates after conservative treatment of partial UCL injuries in overhead athletes along with descriptive components of each conservative intervention to identify an effective evidence-based nonoperative rehabilitation protocol.

DATA SOURCES

Articles in PubMed, CINAHL, MEDLINE, Academic Search Complete, and SPORTDiscus were identified in October 2018 based on the following terms: overhead athlete, ulnar collateral ligament, nonoperative treatment, and return to play.

STUDY SELECTION

Seven retrospective, level 4 studies (n = 196) qualified for analysis.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Study design, level of evidence, demographics, sample size, sports involved, level of competition, grade or type of UCL diagnosis, conservative treatment components, and percentage RTP were extracted.

RESULTS

Overall, RTP rates after conservative treatment ranged between 42% and 100% (mean, 78% ± 20%). The most frequently reported components of rehabilitation protocols were (1) a period of rest, (2) stretching, (3) strengthening, and (4) a throwing program. Platelet-rich plasma injections were included in 5 (71%) of the 7 protocols with a rehabilitation period.

CONCLUSION

Conservative treatment is a viable option for partial UCL tears in overhead athletes. A successful rehabilitation protocol includes the use of patient-reported outcomes, a sport-specific tailored treatment plan, kinetic chain strengthening, and an interval throwing program. Factors such as age, grading of tear, level of play, sport, and athlete's perceived well-being should all be considered during treatment decisions.