How much valgus instability can be expected with ulnar collateral ligament (UCL) injuries? A review of 273 baseball players with UCL injuries

The influence of a single 30-pitch session on elbow laxity in adolescent and collegiate baseball pitchers

BACKGROUND

Ulnar collateral ligament (UCL) injuries are a source of significant injury among baseball players, and are increasingly evaluated under ultrasound. The purpose of this study is to determine the effect of a single session of pitching upon UCL thickness and laxity via a cross sectional, controlled ultrasonographic study. We hypothesize that a single session of pitching will cause the ulnar collateral ligament to thicken and become more lax.

METHODS

This was a cross sectional comparative study of collegiate and high school pitchers. Pitchers underwent an ultrasonographic assessment of the UCL before and after a thirty-pitch bullpen warm-up. Laxity was measured as the change in the distance between the ulna and the trochlea with and without a 5-pound weight held in hand with the elbow at 30° of flexion. Pre- and post-throwing UCL thickness and medial laxity were statistically compared with paired tests.

RESULTS

Our study included 15 pitchers, 8 collegiate and 7 high school level athletes. All played baseball at least 6 days a week, and nearly all played for at least 10 months a year. Pitchers reported a peak velocity of 89 ± 6 (77 to 98) miles per hour. In the prior season, these pitchers pitched 56 ± 33 (10 to 120) games, throwing 62 ± 34 (25-140) pitches per game on average. After throwing, there was significantly less UCL laxity (P = .013). Post-throwing laxity was significantly positively correlated with both peak pitch velocity (P = .009) and an average number of pitches thrown per game (P = .10).

CONCLUSION

Throwing 30 pitches significantly decreases medial elbow laxity with stress, possibly due to flexor-pronator activation. Post-throwing medial laxity is correlated with both peak pitch velocity and average number of pitches thrown per game. Future studies should be conducted to determine the number of throws at which laxity begins to increase, as this may provide a workload management guideline for injury prevention.

High variability among surgeons in evaluation, treatment, and rehabilitation of medial ulnar collateral ligament injuries

Hypothesis and/or Background

The incidence of elbow medial ulnar collateral ligament (MUCL) injuries has been increasing, leading to advances in surgical treatments. However, it is not clear that there is consensus among surgeons regarding diagnostic imaging, the indications for acute surgery and postoperative rehabilitation. The purpose of this study is evaluate surgeon variability in the presurgical, surgical, and postsurgical treatment of MUCL injuries regarding the imaging modalities used for diagnosis, indications for acute surgical treatment, and postoperative treatment recommendations for rehabilitation and return to play (RTP). Our hypothesis is that indications for acute surgical treatment will be highly variable based on MUCL tear patterns and that agreement on the time to RTP will be consistent for throwing athletes and inconsistent for nonthrowing athletes.

Methods

A survey developed by 6 orthopedic surgeons with expertise in throwing athlete elbow injuries was distributed to 31 orthopedic surgeons who routinely treat MUCL injuries. The survey evaluated diagnostic and treatment topics related to MUCL injuries, and responses reaching 75% agreement were considered as high-level agreement.

Results

Twenty-four surgeons responded to the survey, resulting in a 77% response rate. There is 75% or better agreement among surveyed surgeons regarding acute surgical treatment for distal full thickness tears, ulnar nerve transposition in symptomatic patients or with ulnar nerve subluxation, postoperative splinting for 1-2 weeks with initiation of rehabilitation within 2 weeks, the use of bracing after surgery and the initiation of a throwing program at 3 months after MUCL repair with internal brace by surgeons performing 20 or more MUCL surgeries per year. There were a considerable number of survey topics without high-level agreement, particularly regarding the indications for acute surgical treatment, the time to return to throwing and time RTP in both throwing and nonthrowing athletes.

Discussion and/or Conclusion

The study reveals that there is agreement for the indication of acute surgical treatment of distal MUCL tears, duration of bracing after surgery, and the time to initiate physical therapy after surgery. There is not clear agreement on indications for surgical treatment for every MUCL tear pattern, RTP time for throwing, hitting and participation in nonthrowing sports.

Differences in Anatomic Adaptation and Injury Patterns Related to Valgus Extension Overload in Overhead Throwing Athletes

The purpose of our study was to determine differences in adaptative and injury patterns in the elbow related to valgus extension overload (VEO) in overhead throwing athletes by age. A total of 86 overhead throwing athletes and 23 controls underwent MRI or MR arthrography (MRA) of the elbow. Throwing athletes were divided by age into three groups: ≤16 years (26 subjects), 17-19 years (25 subjects), and ≥20 years (35 subjects). Consensus interpretation of each MRI was performed, with measurements of ulnar collateral ligament (UCL) thickness and subchondral sclerosis at the radial head, humeral trochlea, and olecranon process. A higher frequency of apophyseal and stress injuries was seen in adolescent athletes and increased incidence of soft tissue injuries was observed in older athletes. Early adaptive and degenerative changes were observed with high frequency independent of age. Significant differences were observed between athletes and controls for UCL thickness (p < 0.001) and subchondral sclerosis at the radial head (p < 0.001), humeral trochlea (p < 0.001), and olecranon process (p < 0.001). Significant differences based on athlete age were observed for UCL thickness (p < 0.001) and subchondral sclerosis at the olecranon process (p = 0.002). Our study highlights differences in anatomic adaptations related to VEO at the elbow between overhead throwing athletes and control subjects, as well as across age in throwing athletes.

Tommy John Ligament Repair with Ulnar Collateral Ligament Internal Brace

Ulnar collateral ligament (UCL) injuries commonly occur in overhead athletes as a result of excess valgus stress on the elbow and can be functionally debilitating, requiring surgical intervention. Since the advent of the first initial UCL reconstruction technique pioneered by Dr. Frank Jobe performed on professional baseball player Tommy John, UCL, or Tommy John Ligament reconstruction has successfully returned athletes to sport following injury and shown enhanced clinical outcomes with minimal complication rates. Tommy John surgery continues to evolve with the development of various techniques over recent years. This technical note describes a UCL repair with an internal brace using knotless suture anchors and aims to contribute to the current literature a technique that is efficacious and reproducible and offers satisfactory stability, functionality, and return to play.

Correlation of Joint Space Widening on Valgus Stress Magnetic Resonance Imaging With Level of Play and Innings Pitched in Professional Pitchers

Background

Previous studies have described various techniques and confirmed the clinical utility of valgus stress radiography and stress ultrasound in overhead athletes. The addition of valgus stress and a high-resolution anatomic assessment of the elbow with magnetic resonance imaging (MRI) in the active throwing position (flexed elbow valgus external rotation [FEVER] view) can add valuable diagnostic or prognostic information in throwing athletes.

Purpose/Hypothesis

The purpose of this study was to evaluate findings on MRI and subsequent performance in professional throwing athletes. It was hypothesized that joint space widening in the FEVER view would be predictive of performance and the risk of subsequent injuries.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

All pitchers on 2 Major League Baseball teams who consented to participate during their preseason screening in 2019 and 2020 underwent standard and FEVER MRI, and performance data from the following season were recorded, including injuries, mean throwing velocity, number of innings pitched, strikeout percentage, walk percentage, weighted on-base average, and level of play reached (not signed, minor league, or major league). Categorical variables were compared using the Fisher exact test or chi-square test, and continuous variables were compared using the Kruskal-Wallis test, as appropriate. Ordered logistic regression was used to determine the independent factors predicting performance.

Results

A total of 91 players underwent preseason imaging, and all players had subsequent performance data available. Multivariate analysis revealed that when controlling for age, mean velocity, history of injuries, presence of symptoms, and history of ulnar collateral ligament reconstruction, increased absolute joint space widening was predictive of a lower level of play (β = -0.63; P = .042). Univariate analysis demonstrated a significant correlation between relative joint space widening and level of play reached (β = -0.54; P = .034). Relative joint space widening remained a significant predictor of level of play (β = -0.87; P = .012) on multivariate analysis. Multivariate analysis also showed that both absolute joint space widening (β = -13.50; P = .012) and relative joint space widening (β = -13.60; P = .026) were predictive of the number of innings pitched in the subsequent season.

Conclusion

The present study demonstrates that findings on MRI with valgus stress correlated with the level of play reached and number of innings pitched in professional throwing athletes.

Comparison of elbow valgus laxity and medial elbow stabilizer parameters during repetitive pitching between high school baseball players with and without a history of medial elbow injury

BACKGROUND

Adolescent baseball players with a history of medial elbow injury are often reinjured during demanding practice sessions or games. The physical characteristics of baseball players with a history of medial elbow injury have been reported in several previous studies, but the nature of their medial elbow stabilizers is unknown. This study investigated the difference in characteristics of elbow valgus laxity and medial elbow stabilizer parameters between baseball players with and without a history of medial elbow injury, prior to and during repetitive pitching.

METHODS

Sixteen high school baseball players with no history of medial elbow injury (No-Injury group) and 14 high school baseball players with a history of medial elbow injury (Injury History group) participated. The participants pitched 100 fastballs. Medial elbow joint-space gapping and strain ratio indicating tissue elasticity of ulnar collateral ligament (UCL) and forearm flexor-pronator muscles (FPMs) were measured by ultrasound before pitching and following each of five 20-pitch blocks. Student t tests and Mann-Whitney U tests were used to compare each parameter between groups.

RESULTS

Medial elbow joint-space gapping and UCL elasticity were not significantly different between the 2 groups in each pitching block (P > .05). The strain ratio of FPMs before pitching and after 100 pitches in the Injury History group were significantly greater than that in the No-Injury group (No-Injury vs. Injury History group: before pitching, 0.47 ± 0.19 vs. 0.68 ± 0.26, P = .016; 100 pitches, 0.35 ± 0.12 vs. 0.53 ± 0.20, P = .007). In the other pitching blocks, there was no significant difference between groups, but the effect size was medium and showed a similar tendency (20 pitches, P = .069, Cohen d = 0.69; 40 pitches, P = .116, Cohen d = 0.59; 60 pitches, P = .102, Cohen d = 0.62; 80 pitches, P = .058, Cohen d = 0.72).

CONCLUSIONS

The results of this study indicate that FPM elasticity at baseline and during repetitive pitching in players with a history of medial elbow injury was harder than in players without injury history. This may suggest that baseball players with a history of medial elbow injury increase support of their previously injured medial elbow by hardening FPM elasticity to counteract elbow valgus stress generated during pitching, which may lead to long-term change in the FPMs. Therefore, physical management for this change may be important to prevent reinjury in baseball players with a history of medial elbow injury.

The Role of Ultrasound in the Evaluation of Elbow Medial Ulnar Collateral Ligament Injuries in Throwing Athletes

PURPOSE OF REVIEW

Although ultrasound (US) imaging is commonly used to evaluate the elbow medial ulnar collateral ligament (mUCL) in throwing athletes, significant technical heterogeneity exists in the published literature and in practice. This has resulted in variable and often ambiguous US diagnostic criteria for mUCL injury. This review summarizes the literature on sonographic evaluation of the mUCL and outlines recommendations for consistent descriptive terminology, as well as future clinical and research applications.

RECENT FINDINGS

Both acute and chronic throwing loads in overhead athletes cause the mUCL to become thicker and more lax on stress testing, and these changes tend to revert after a period of prolonged rest. Stress US (SUS) can aid in the diagnosis of mUCL tears and may help identify athletes at risk of mUCL injury. Variability exists in terminology, elbow flexion angle, amount of stress applied, and technique of stress testing. Recent studies have suggested an injured elbow stress delta (SD-change in ulnohumeral joint (UHJ) space with valgus stress) of 2.4 mm and a stress delta difference (SDD-side-side difference in SD) of 1 mm each denote abnormal UHJ laxity due to mUCL injury. US imaging is a powerful and widely accessible tool in the evaluation elbow mUCL injuries. Sonologists should consider how their US techniques compare with published methods and use caution when applying diagnostic criteria outside of those circumstances. Currently, an SD of 2.4 mm and an SDD of 1 mm provide the best diagnostic accuracy for mUCL tears requiring surgery. Finally, preliminary work suggests that shear wave elastography may be helpful in evaluating the biomechanical properties of the mUCL, but additional research is needed.

The relationship between changes in elbow valgus laxity and forearm flexor strength during repetitive pitching

This study examined the changes in the medial elbow joint space width and forearm flexor strength due to repetitive pitching and analysed the relationships among these factors. Thirty-one collegiate baseball players pitched seven sets of 15 pitches each. The medial elbow joint space width, grip strength, and forearm flexor strengths were measured before pitching and after each set. These parameters were compared at baseline and after pitching for each set. Additionally, the relationships between changes in the medial elbow joint space and forearm flexor strength were examined for each set. The medial elbow joint space width significantly increased after four sets compared to baseline values. Compared to baseline values, grip strength decreased significantly after one set, wrist flexion and radial deviation after six, and ulnar deviation after five. However, changes in the medial joint space compared to baseline values after each set were not significantly correlated with changes in forearm flexor strength variables. Therefore, repetitive pitching causes an increase in elbow valgus laxity and a decrease in forearm flexor strength. However, the decrease in forearm muscle strength does not explain the increase in elbow valgus laxity.

Medial Ulnar Collateral Ligament Injuries in Contact Athletes

PURPOSE OF REVIEW

The purpose of this article is to review medial ulnar collateral ligament (UCL) injuries in contact athletes. UCL injuries in overhead throwing athletes are typically chronic attenuation due to repetitive valgus stress on the elbow during the throwing motion. As such, UCL reconstruction is commonly performed for these athletes. In contrast, UCL injuries in contact athletes are usually acute ligament tears or avulsions of a ligament with otherwise normal tissue. Nonoperative treatment is typically the first-line treatment for partial injuries. UCL repair may work well for acute complete injuries and may avoid the donor site morbidity of UCL reconstruction.

RECENT FINDINGS

Most of the literature regarding UCL injuries have been performed in baseball players. Historically, UCL repair has had poor outcomes in baseball players due to the chronic ligament attenuation. Therefore, much of the recent literature has focused on outcomes of UCL reconstruction, which are generally excellent. However, there is a paucity of literature studying outcomes of UCL injuries in contact athletes and those studying UCL repair. One recent study looked at a new technique for UCL repair with collagen-coated fiber tape augmentation in baseball players and found good short-term outcomes. UCL injuries in contact athletes occur typically as acute tears or avulsions. While UCL reconstruction has typically been recommended as the accepted treatment for UCL tears that require operative treatment, UCL repair may be a good alternative in contact athletes.

Medial elbow joint space gapping associated with repetitive baseball pitching in preadolescent baseball players

BACKGROUND

The baseball pitching motion creates valgus stress to the medial elbow, which contributes to increased medial elbow joint space gapping. The musculoskeletal systems of preadolescent baseball players are immature compared with those of adults, but it is unclear whether the repetitive pitching action causes an increase in medial elbow joint space gapping. This study aimed to examine differences in medial elbow joint space gapping based on the pitch count of preadolescent baseball players compared with those of adult players.

METHODS

The participants were 11 healthy preadolescent baseball players and 12 college students with baseball experience. They threw 60 maximal-effort pitches arranged into 4 sets of 15 pitches. The medial elbow joint space was measured ultrasonographically with the forearm weight before pitching and following every set of 15 pitches. Repeated-measures analysis of variance and the Bonferroni post hoc test were used to compare the medial elbow joint space among the 5 pitching sets (before pitching and after 15, 30, 45, and 60 pitches) and between the groups of preadolescent baseball players and college students.

RESULTS

There was no significant change in the medial elbow joint space gapping of the dominant elbow based on age/pitch count (F = 0.42, P = .796). There was a significant effect of pitch count (F = 30.28, P < .001) and between-group effects (F = 4.56, P = .045). The medial elbow joint space gapping increased significantly after 60 pitches in preadolescent baseball players (P = .023) and college students (P = .021). The medial elbow joint space gapping in preadolescent baseball players was significantly wider than that in college students (P = .007 before pitching, P = .027 at 15 pitches).

CONCLUSION

Sixty repetitive pitches contributed to an increase in the medial elbow joint space gapping, regardless of age. The results of this study provide further evidence when considering pitching limitations.

Changes in Medial Elbow Joint Space When Elbow Valgus Stress Is Applied at Different Limb Positions and Loads In Vivo

Background:

Ulnar collateral ligament (UCL) injury is a common sports injury among overhead-throwing athletes and causes medial elbow pain and instability. UCL injury is generally diagnosed based on symptoms, physical findings, and image evaluation. To standardize the method for evaluating elbow valgus instability, more information is needed regarding changes in the medial elbow joint space (JS) in healthy elbows.

Purpose/Hypothesis:

The purpose of this study was to measure the JS during the application of elbow valgus stress at different elbow flexion angles and loads and to clarify the presence of defensive muscle contractions during elbow valgus stress. It was hypothesized that the JS will differ according to different limb positions and loads and that defensive contractions will occur when elbow valgus stress is >90 N.

Study Design:

Controlled laboratory study.

Methods:

Elbow joints on the nondominant side were examined in 20 healthy male university students (mean age, 21 ± 0.2 years) at 30°, 60°, and 90° of elbow flexion. To create valgus stress on the elbow, loads of 30, 60, 90, 120, and 150 N were applied with a Telos stress device and with gravity stress on the forearm. The medial JS was measured ultrasonographically during the application of elbow valgus stress. Electrodes were attached to the pronator teres muscle, and defensive muscle contractions were measured using electromyography during the application of elbow valgus stress. Repeated-measures analysis of variance and paired t tests were used to compare the JS at each elbow angle and each valgus stress load, and the Bonferroni method was used as a post hoc test.

Results:

At 30° of elbow flexion, the JS was significantly higher at 30 N versus 0 N and at 60 N versus 0 or 30 N (P ≤ .018 for all). At 60° of flexion, the JS was significantly higher at 30 N versus 0 N, at 60 N versus 0 and 30 N, and at 90 N versus 0, 30, and 60 N (P ≤ .024 for all). At 90° of elbow flexion, the JS was significantly higher at 30 N versus 0 N and at 60 N versus 0 and 30 N (P ≤ .028 for all). Defensive muscle contraction did not occur at any elbow flexion angles at elbow valgus stress ≤60 N.

Conclusion:

The lack of muscular contraction at elbow valgus stress ≤60 N may reflect the function of the medial collateral ligament.

Clinical Relevance:

Elbow valgus stress ≤60 N allows for the evaluation of the joint opening.

FEVER: The Flexed Elbow Valgus External Rotation View for MRI Evaluation of the Ulnar Collateral Ligament in Throwing Athletes-A Pilot Study in Major League Baseball Pitchers

Background: Ulnar collateral ligament (UCL) injuries are common in throwing athletes due to repetitive extreme valgus stress during overhead throwing maneuvers. Conventional positioning for elbow MRI provides suboptimal rendering of the UCL. Objective: To perform a prospective pilot study assessing the impact of a flexed elbow valgus external rotation (FEVER) view on ulnotrochlear (UT) joint space measurement and reader evaluation of the UCL when incorporated into standard elbow MRI in throwing athletes. Methods: A total of 44 Major League Baseball pitchers underwent elbow MRI including standard sequences and a coronal fat-saturated proton density-weighted sequence in the FEVER view that uses specific positioning maneuvers and sandbags to immobilize the elbow in valgus stress and visualize the UCL parallel to its long axis. Patients recorded pain during FEVER view [0 (none) to 10 (maximal)]. Two radiologists independently evaluated standard and FEVER views to measure the UT joint space, assess confidence in UCL-related findings, and assess the UCL as normal or abnormal. Results: Pain during FEVER view was: 0 (n=29), 1-3 (n=11), 4-7 (n=4), 8-10 (n=0). Intrareader agreement for UT joint space measurement was higher for FEVER [intraclass correlation coefficient (ICC)=0.92] than standard (ICC=0.54) views. Averaged between readers, mean UT joint space increase on FEVER compared with standard view was 1.80 mm (95% CI: 1.58, 2.03). Confidence was higher for FEVER than standard view for reader 1 for assessment of the UCL as normal versus abnormal (mean increase in confidence of 0.41), intensity of abnormal signal (0.44), injury grade (0.98), and retraction (0.20), and for reader 2, assessment of the UCL as normal versus abnormal (0.50), location of abnormal signal (0.42); intensity of abnormal signal (0.47), injury grade (0.89), and retraction (0.50). Readers 1 and 2 classified 3 and 2 additional UCLs as abnormal on FEVER compared with standard view; neither reader classified any UCL as abnormal in standard view but normal in FEVER view. Conclusion: The increased joint space width confirms elbow valgus stress with FEVER view. Diagnostic confidence increased, and additional UCLs were identified as abnormal. Clinical Impact: The FEVER view may improve MRI evaluation of the UCL in throwing athletes.

Diagnostic Imaging of Ulnar Collateral Ligament Injury: A Systematic Review

BACKGROUND

Ulnar collateral ligament (UCL) injuries can be debilitating in overhead athletes. Accurate diagnosis is important; however, several imaging modalities are available for the assessment of UCL injuries.

PURPOSE

To provide a comprehensive review of published literature regarding the diagnostic capabilities of different imaging modalities for UCL tears.

METHODS

PubMed, Medline, and Embase were queried for peer-reviewed literature published between January 1947 and June 4, 2019, pertaining to diagnostic imaging of UCL tears. Articles assessing static and stress radiography, ultrasound, magnetic resonance imaging (MRI), MRI with arthrography (MRA), and computed tomography arthrography of the UCL were included. Studies were excluded if imaging results were not compared with intraoperative diagnosis, as intraoperative findings are generally considered the gold standard for diagnostic comparison. The articles were assessed per the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines and reviewed with the Quality Assessment of Diagnostic Accuracy Studies, version 2 (QUADAS-2) assessment.

RESULTS

The literature search yielded 2478 articles, of which 15 were included in this review. Potential bias was noted in each QUADAS-2 subsection. Multiple studies demonstrate an association between UCL tears and osseous abnormalities identified on static radiographs; however, the use of static or nonstressed radiographs is not recommended for specific evaluation of UCL injuries. Conventional ultrasound was 81% sensitive and 91% specific, as compared with 96% and 81% for stress ultrasound, respectively. The sensitivity and specificity of MRI ranged from 57% to 100% and 89% to 100%. The sensitivity of computed tomography arthrography ranged from 63% to 86%. The sensitivity and specificity of MRA ranged from 81% to 100% and 91% to 100%.

CONCLUSION

Of the currently available imaging modalities, MRA provides the best combination of sensitivity and specificity of the evaluation of the UCL. Further research comparing ultrasound with MRA is needed.

Prediction and Potential Preventions for the Development of Posttraumatic Osteoarthritis after the Terrible Triad Injury: A Multicenter Risk Factors Study

Objective

A multicenter study to evaluate risk factors for the development of moderate or severe posttraumatic osteoarthritis (PTOA) and to find potential preventions.

Methods

We conducted a retrospective multicenter study including the terrible triad injury (TTI) patients with surgical treatment from January 2007 to November 2014. Demographics, injury information, and treatment history were obtained retrospectively. According to the Broberg and Morrey criterion, 198 included patients were sorted into two groups: the mild or no PTOA and moderate or severe PTOA. Uni- and multivariate logistic regression analyses were used to identify risk factors for moderate or severe PTOA.

Results

Moderate or severe PTOA was present in 64 patients (32.3%). Significant risk factors were Mason III radial head fracture (OR 4.049, 95% CI 1.877-8.736, p < 0.001), medial collateral ligament injury (OR 5.120, 95% CI 1.261-20.790, p = 0.022), and heavy use of elbow (OR 2.333, 95% CI 1.060-5.136, p = 0.035). Besides, patients suffered subluxation (p = 0.007) and those with more risk factors had a higher risk to develop moderate or severe PTOA.

Conclusions

Moderate or severe PTOA was common after the TTI. Patients need to be counseled about avoiding heavy use of the elbow, especially for those with Mason III radial head fractures. Surgeons should be aware of the recurrent instability of the elbow.

Injured vs. uninjured elbow opening on clinical stress radiographs and its relationship to ulnar collateral ligament injury severity in throwers

BACKGROUND

Stress radiography measures medial joint space opening of the elbow, but its value in the management of throwing athletes is unclear. The purpose of this study was to analyze the relationship between medial joint opening (gapping and excess opening) and ulnar collateral ligament (UCL) injury severity on magnetic resonance imaging, as well as to explore factors related to the unexpected finding of a greater opening of the uninjured elbow compared with the injured elbow (negative excess opening) with valgus stress radiography.

METHODS

Medial joint space measurements were independently performed by 2 raters in a clinical series of 74 patients evaluated with standardized valgus stress radiography as part of their clinical workup for throwing-related medial elbow pain. Demographic data were collected by chart review, and UCL injury severity was classified based on available imaging into intact UCLs, partial-thickness tears of the anterior bundle, or full-thickness tears of the anterior bundle.

RESULTS

Joint gapping was related to UCL injury severity (P = .003), and group-level comparison showed a difference among tear severity groups (P = .050). Excess opening was not significantly related to UCL injury severity (P = .109). A negative excess opening was observed in 22% of patients, but no factors corroborating guarding or a mechanical explanation were significant for a decreased medial joint opening of the injured elbow compared with the uninjured elbow.

CONCLUSIONS

Medial joint gapping was correlated to UCL injury severity in throwing athletes with medial elbow pain and a clinical suggestion of UCL injury, but no association between injury severity and excess opening was observed in this clinical series, which may limit the usefulness of stress radiography in the clinical workup of throwing athletes.

Ulnar Collateral Ligament Injuries of the Elbow in the Throwing Athlete

UPDATE

This article was updated on February 26, 2018, because of a previous error. On pages 1 and 7, in the author byline section, the authors' names that had read "Andrew Harris" and "Brett Owens" now reads "Andrew P. Harris" and "Brett D. Owens."

Ulnar collateral ligament insufficiency affects cubital tunnel syndrome during throwing motion: a cadaveric biomechanical study

BACKGROUND

In throwing athletes, cubital tunnel syndrome and insufficiency of the ulnar collateral ligament (UCL) are common pathologic processes of the elbow. The objective of this study was to investigate the effect of UCL tears on ulnar nerve elongation in the simulated throwing position.

METHODS

Eight fresh frozen cadaveric upper limbs were tested at the simulated late cocking to acceleration phase in the throwing motion using an elbow testing system. Elbow valgus laxity and ulnar nerve length and strain under 2 Nm of applied valgus torque (maximum torque in cadaveric elbow) were evaluated. Paired t-tests were used to compare all data between intact UCLs and UCLs after complete transection of the anterior oblique ligament. Linear regression analysis was used to investigate relationships between elbow valgus laxity and ulnar nerve strain.

RESULTS

Elbow valgus laxity significantly increased after transection of the UCL. Ulnar nerve length after UCL transection was significantly greater than that in the intact condition at 60° (P = .006) and 90° of elbow flexion (P < .0001). In addition, ulnar nerve strain was positive (increased) at 60° and 90° of elbow flexion. Maximum ulnar nerve strain at 90° of elbow flexion was 3.9% ± 0.9% when the UCL was intact and 6.8% ± 0.7% after transection. UCL transection yielded significant positive correlation between elbow valgus laxity and ulnar nerve strain (P = .006; r = .4714).

CONCLUSION

Increased elbow valgus laxity due to UCL insufficiency may cause elongation of the ulnar nerve and exacerbate cubital tunnel syndrome during the throwing motion.

Medial elbow stability assessment after ultrasound-guided ulnar collateral ligament transection in a cadaveric model: ultrasound versus stress radiography

BACKGROUND

The ulnar collateral ligament (UCL), consisting of 3 bundles, is the primary medial restraint in the elbow. Recent research has demonstrated that ultrasound is an effective modality to evaluate the medial elbow, whereas stress radiography is standard practice in the measurement of medial elbow laxity. This study (1) compared dynamic ultrasound (US_D) with stress radiography in the evaluation of UCL insufficiency and (2) further evaluated the contribution of the anterior bundle of the UCL to medial elbow stability.

METHODS

Stress radiographs and US_D were used to obtain coronal plane measurements of the medial joint space of 16 cadaveric elbows before and after US_D-guided isolated transection of the anterior bundle of the UCL. Measurements were performed with and without a valgus stress applied to the elbows, and gapping of the ulnohumeral joint space was documented.

RESULTS

Transection of the anterior bundle of the UCL resulted in 1.5 mm and 1.7 mm of additional gapping in the ulnohumeral joint as measured with stress radiographs and US_D, respectively. No differences were recorded in the ulnohumeral gapping measurements between stress radiography and US_D.

CONCLUSIONS

The lack of difference between measurements reveals US_D is as reliable as stress radiography in evaluating the medial ulnohumeral joint space and continuity of the UCL while eliminating radiation exposure and minimizing cost of the diagnostic examination. The increase in ulnohumeral gapping with isolated transection of the anterior bundle of the UCL demonstrates its significant contribution to medial elbow stability.

Elbow Ulnar Collateral Ligament Reconstruction Using the Novel Docking Plus Technique in 324 Athletes

BACKGROUND

This retrospective case series examined 324 athletes who received elbow ulnar collateral ligament (UCL) reconstruction by a single surgeon in a private practice over a 9-year period. The novel Docking Plus technique for elbow UCL reconstruction in 324 athletes provided good or excellent Conway score results in 88% of patients. The preponderance of previous studies examining UCL reconstruction outcomes were performed by surgeons at one of only three institutions (Andrews Institute, Hospital for Special Surgery, Kerlan Jobe Orthopedic Clinic).

METHODS

Patients undergoing UCL reconstruction from November 2005 to December 2014 were identified and contacted with a mailed survey and phone call. These patients were given a subjective 19 question survey assessing their outcomes from surgery.

RESULTS

The participants who responded to our survey were 90% male and 77% baseball players, 73% of which were pitchers. Of the baseball players who responded, 51.9% were in high school at the time of their surgery, 37% college, 6.5% minor leagues, and 2.2% in Major League Baseball. After surgery, 36% of survey responders returned to a higher level of competition than previously. For example, a high school athlete who had UCL reconstruction and went on to pitch in college. Further, 45% returned to the same level, and 7% returned to a lower level. Subjective "satisfaction," was reported in 92% of responders and 97.2% reported that, "having surgery was a good idea." Symptom onset in the responding athletes was 58.9% sudden, and 41.1% gradual. Overall, 90.9% of respondents returned to play in less than 1.5 years while 6.3% never were able to return. Re-tear occurred in 2.5% of patients, while 8.8% had subjective nerve dysfunction for at least 3 months following surgery.

CONCLUSION

The Docking Plus technique can produce excellent subjective and objective results in athletes. Further study is warranted to see the effects of this procedure in other settings and determine which method of reconstruction or repair is superior.

Ultrasound-Assisted Assessment of Medial Elbow Stability

OBJECTIVES

An assessment of medial elbow stability is essential to the patient with an ulnar collateral ligament injury. Ultrasound imaging can be used to assess medial elbow stability. This study determined the effect of the elbow flexion angle on the medial elbow joint space during clinical tests of medial elbow stability.

METHODS

Ultrasound images of the nondominant elbow were collected during 3 tests of medial elbow stability: valgus stress test, weighted valgus test, and milking maneuver. The elbow flexion angle increased between the valgus stress test and milking maneuver. The width of the medial joint space was measured on ultrasound images collected in unstressed and stressed conditions.

RESULTS

Across test conditions, the medial joint width was greater in the stressed condition (mean ± SD, 3.7 ± 0.1 mm) than in the unstressed condition (2.9 ± 0.09 mm). The medial elbow joint space width was less (mean difference, 0.16 ± 0.01 mm; P = .01) in the milking maneuver position compared to the valgus stress test positions.

CONCLUSIONS

This study provides evidence that changes in the width of the medial elbow during clinical evaluation of the unimpaired elbow can be detected by ultrasound. Changing the elbow flexion angle did not affect the change in width of the medial elbow during valgus loading.

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.

Revision Ulnar Collateral Ligament Reconstruction

Ulnar collateral ligament injuries continue to occur despite efforts to educate pitchers, coaches, and families at the amateur and professional levels about pitch counts, mechanics, and injury prevention. Although the data on the incidence of ulnar collateral ligament reconstructions are inconclusive, an increase in these reconstructions may mean a corresponding increase in the number of reconstruction failures and revision reconstruction surgeries. Less is known about the outcomes of revision ulnar collateral ligament reconstruction; not unexpectedly, early results are not as promising as those observed with primary reconstruction. In response, interest in revision techniques, rehabilitation, and outcomes of revision ulnar collateral ligament reconstruction surgeries has grown.

The effect of repetitive baseball pitching on medial elbow joint space gapping associated with 2 elbow valgus stressors in high school baseball players

BACKGROUND

To prevent elbow injury in baseball players, various methods have been used to measure medial elbow joint stability with valgus stress. However, no studies have investigated higher levels of elbow valgus stress. This study investigated medial elbow joint space gapping measured ultrasonically resulting from a 30 N valgus stress vs. gravitational valgus stress after a repetitive throwing task.

METHODS

The study included 25 high school baseball players. Each subject pitched 100 times. The ulnohumeral joint space was measured ultrasonographically, before pitching and after each successive block of 20 pitches, with gravity stress or 30 N valgus stress. Two-way repeated measures analysis of variance and Pearson correlation coefficient analysis were used.

RESULTS

The 30 N valgus stress produced significantly greater ulnohumeral joint space gapping than gravity stress before pitching and at each successive 20-pitch block (P < .01). For the 2 stress methods, ulnohumeral joint space gapping increased significantly from baseline after 60 pitches (P < .01). Strong significant correlations were found between the 2 methods for measurement of medial elbow joint space gapping (r = 0.727-0.859, P < .01).

CONCLUSIONS

Gravity stress and 30 N valgus stress may produce different effects with respect to medial elbow joint space gapping before pitching; however, 30 N valgus stress appears to induce greater mechanical stress, which may be preferable when assessing joint instability but also has the potential to be more aggressive. The present results may indicate that constraining factors to medial elbow joint valgus stress matched typical viscoelastic properties of cyclic creep.

Avoiding Tommy John Surgery: What Are the Alternatives?

The number of ulnar collateral ligament (UCL) reconstructions being performed has risen sharply in recent years, most notably in the young amateur athlete. While successful outcomes have been reported with reconstruction, the surgery and the associated rehabilitation timeline may be difficult for the nonelite athlete to incur. Return-to-play expectations, along with level of competition, should help guide surgeons in exploring management options. While reconstruction remains a mainstay, focused research exploring nonreconstructive options has expanded. This review discusses the clinical approach to those with UCL injury, including current support for rehabilitation, biologic strategies, and available repair or augmentation alternatives.

The Effects of Elbow Bracing on Medial Elbow Joint Space Gapping Associated With Repetitive Throwing in High School Baseball Players

Background:

Throwing athletes risk medial elbow injury from extreme valgus stress generated across the medial elbow during throwing. Braces have been developed to protect the elbow joint; however, no previous study has investigated the effects of elbow bracing on medial elbow joint space gapping associated with repetitive throwing.

Hypothesis/Purpose:

The purpose of this study was to investigate the effects of elbow bracing on medial elbow joint space gapping during repetitive throwing. Our hypothesis was that an elbow brace may reduce mechanical stress on the elbow by reducing medial elbow joint space gapping.

Study Design:

Controlled laboratory study.

Methods:

Twenty-five high school baseball players participated in this study. Each subject pitched 100 times under 2 conditions: control (without elbow brace) and elbow brace. The ulnohumeral joint space was measured ultrasonically before pitching and after every block of 20 pitches. Measurement of the ulnohumeral joint space was carried out using ultrasound with the forearm hanging by the side. Two-way repeated-measures analysis of variance and post hoc tests were used to compare ulnohumeral joint space with repeated pitching and between the elbow brace and control conditions.

Results:

In the control condition, ulnohumeral joint space after 60 pitches was significantly greater than that before pitching (P < .01). In contrast, in the elbow brace condition, ulnohumeral joint space was not significantly different after repeated pitching. When comparing these 2 conditions, ulnohumeral joint space in the control condition was significantly greater than that in the elbow brace condition after 60 pitches (P < .01).

Conclusion:

An elbow brace has the effect of preventing medial elbow joint space gapping with repeated throwing when determined ultrasonically by measuring the ulnohumeral joint space under gravity load.

Clinical Relevance:

An elbow brace worn during baseball pitching practice may help reduce mechanical stress on the elbow by reducing medial elbow joint space gapping.

Clinical interpretation of asymptomatic medial collateral ligament injury observed on magnetic resonance imaging in adolescent baseball players

PURPOSE

Magnetic resonance imaging (MRI) of medial collateral ligament (MCL) injury of the elbow was often observed in asymptomatic adolescent baseball players. We aimed to clarify the clinical interpretation of "asymptomatic MCL injury observed on MRI" by comparing MRI, ultrasonography (US), and physical findings.

MATERIALS AND METHODS

Sixty-four asymptomatic adolescent baseball players (mean 11.2 years) were enrolled. An open-type 0.2T MRI was used. MCL function was evaluated by measuring the opening of the ulnohumeral joint using US. Physical findings included MCL tenderness, the moving valgus test, and the Milking test. The correlation between MRI and US, and MRI and physical findings were analyzed.

RESULTS

Thirty-four subjects (53.1%) showed MCL injury by MRI. The mean laterality of the ulnohumeral joint opening showed no significant difference (P = 0.16) between the group with (0.29 ± 1.06 mm) and without (0.08 ± 0.96 mm) MCL injury on MRI. There was no correlation between MRI and physical findings except for a weak correlation between subjects with positive Milking test and MCL injury on MRI (φ coefficient = 0.3, P = 0.02).

CONCLUSION

'Asymptomatic MCL injury on MRI' had little correlation to ligament dysfunction. It might represent the transition period to MCL thickening called "adaptation."

Magnetic resonance imaging-based classification for ulnar collateral ligament injuries of the elbow

BACKGROUND

Magnetic resonance imaging (MRI) arthrography has been considered the gold standard for imaging ulnar collateral ligament (UCL) injuries. No classification system has been described for UCL tears to help discuss and guide treatment options. We propose that an MRI-based UCL classification system would correlate with valgus laxity and help predict surgical management.

METHODS

The MRIs from 240 patients who underwent UCL reconstruction were reviewed and classified according to a system based on severity and location of the UCL injury. Bilateral elbow valgus stress radiographs were used to compare the amount of valgus laxity associated with each grade of UCL injury. Additional data from the imaging review included intraligamentous calcifications, T-sign presence, and a newly described "vacuum sign."

RESULTS

The amount of valgus stress opening increased with the classification severity as follows: type I, 0.13 mm; type II, 0.20 mm; type III, 0.63 mm; and type IV, 0.76 mm.

CONCLUSIONS

We propose a new classification for UCL injuries based on MRI findings that helps predict valgus laxity, improve communication, and guide treatment for UCL pathology in throwing athletes.

Optimal Elbow Angle for Sonographic Visualization of the Ulnar Collateral Ligament

OBJECTIVE

To formally examine the sonographic appearance of the elbow ulnar collateral ligament (UCL) at 30° versus 70° of elbow flexion in asymptomatic baseball pitchers.

DESIGN

A prospective, cross-sectional design.

SETTING

Sports medicine clinic in a tertiary academic medical center.

PARTICIPANTS

Thirty asymptomatic adolescent baseball pitchers 13-18 years of age (mean 15.8 years), with at least 3 years of continuous pitching experience and no significant history of elbow pain or injury.

METHODS

Static sonographic images of the bilateral UCLs were obtained at 30° and 70° of elbow flexion by a single experienced examiner. Images were anonymized and randomized into a slide set. Three clinicians with different levels of ultrasound experience reviewed the static 30° and 70° images for each elbow and chose their preferred image based on UCL conspicuity. The clinicians reviewed a re-randomized slide set 1 week later. A different study co-investigator measured UCL cross-sectional area (CSA) on all images using ultrasound machine electronic calipers.

MAIN OUTCOME MEASURES

Preference for the sonographic conspicuity of the UCL at 30° versus 70° of elbow flexion, and UCL CSA at 30° versus 70° of flexion.

RESULTS

Each clinician demonstrated a significant preference for UCL images obtained at 70° of flexion when compared to those obtained at 30° (80.3% overall preference for 70°, P < .001). There was no statistically significant effect of clinician experience or arm dominance on image preference. The sonographically determined CSA of the UCLs were on average 1.4 mm(2) greater at 70° than at 30° of flexion (P < .001) when combining dominant and nondominant arms.

CONCLUSIONS

Static sonographic evaluation of the UCL at 70° of elbow flexion should be integrated into UCL imaging protocols. Furthermore, when performing sonographically guided procedures targeting the UCL, clinicians should consider positioning the elbow at >30° of flexion to optimize UCL conspicuity and CSA.