Back to Authors

Chalmers, Peter N.

https://orcid.org/0000-0002-1275-0285

Mayo Clinic

University of Utah

Citations 14

Clinical Utility of the Moving Valgus Stress Test and Milking Maneuver for Medial Ulnar Collateral Ligament Injuries of the Elbow
Sciascia, Aaron D. , Chalmers, Peter, Smith, Matthew V. , Griffith, Timothy B. , Erickson, Brandon, Freehill, Michael T., Safran, Marc, Hardaway, Austin, Azar, Frederick M., Brolin, Tyler, Spence, David, Jones, Grant, Freehill, Michael T. , Sciascia, Aaron , Camp, Christopher L. , Griffith, Timothy Bryan , Freehill, Michael T , Bowman, Eric N. , Chalmers, Peter N. , Wolf, Brian R. , Safran, Marc R. , Azar, Frederick M. , Brolin, Tyler J. , Spence, David D. , Cox, Charles L. , LeClere, Lance E. , Jones, Grant

The American Journal of Sports Medicine | May 6, 2026 | Volume: 54 | Issue: 8 | Pages: 1993-2002

10.1177/03635465261439107 Get It

Background: Several special tests for detecting medial ulnar collateral ligament (MUCL) injuries of the elbow have been described, but data on the clinical utility of these tests are limited. Purpose: To determine the clinical utility of selected elbow special tests to detect MUCL injuries in an athletic population. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 84 consecutive patients with sports-related elbow pain underwent a standardized clinical examination. Overall, 6 special tests (moving valgus stress test, static valgus stress test, modified valgus stress test, milking maneuver, pronation flexion resistance test, and temple/cheek press test) were performed. Sensitivity, specificity, accuracy, positive/negative predictive value, and positive/negative likelihood ratio (LR+ and LR–, respectively) were calculated for individual tests and combinations of tests to detect MUCL injuries. Higher values for the LR+ and lower values for the LR– represent stronger clinical utility. Results: For detecting MUCL injuries, the moving valgus stress test resulted in the highest sensitivity (98%) and accuracy (93%) with the lowest LR– (2%). The milking maneuver had the highest LR+ (5.1) with the second highest sensitivity (77%) and accuracy (79%). The pronation flexion resistance test and the temple/cheek press test had the lowest LR+ (1.5 and 1.8, respectively) and highest LR– (94% and 95%, respectively) in addition to the lowest sensitivity (16% and 9%, respectively) and accuracy (33% and 30%, respectively). No combination of tests resulted in increased clinical utility. Conclusion: The moving valgus stress test and milking maneuver demonstrated acceptable clinical utility in which the moving valgus stress test was better for ruling out MUCL injuries and the milking maneuver was better at ruling in MUCL injuries. There was no added value when combining the 2 tests together or with other maneuvers.
Poster 46: Trends and Outcomes of Medial Ulnar Collateral Ligament Repair with Internal Brace, Isolated Reconstruction, and ’Hybrid’ Reconstruction with Internal Brace in Professional Baseball Players: A Matched Cohort Analysis
Griffith, Timothy B. , Chalmers, Peter N., Hebert, Elizabeth, Griffith, Timothy Bryan , Pan, Xuankang , Erickson, Brandon J. , Chalmers, Peter N. , Hebert, Elizabeth, Camp, Christopher L.

Orthopaedic Journal of Sports Medicine | September 26, 2025 | Volume: 13 | Issue: 9_suppl3 | Pages: No page available

10.1177/2325967125s00157 Get It

Objectives: There is a paucity of research comparing the outcomes of medial ulnar collateral ligament (MUCL) repair with internal bracing to isolated MUCL reconstruction in professional baseball players. Further, the practice of supplementing a MUCL reconstruction with an internal brace, a "hybrid" reconstruction, has increased in the surgical treatment of MUCL injuries for professional baseball players, without any currently known published research defining the clinical outcomes of this modification. We sought to investigate the trends and outcomes of MUCL repair with internal bracing and "hybrid" MUCL reconstruction with internal bracing. Using a matched cohort analysis, we also sought to compare the clinical outcomes of both MUCL repair with internal bracing and "hybrid" MUCL reconstruction with internal bracing to isolated MUCL reconstructions, without internal bracing, in professional baseball players. Methods: The MLB Health and Injury Tracking System was used to identify all professional baseball players who underwent MUCL surgery, regardless of surgery technique, from 2010 to 2023. Professional players of all levels (MLB and MiLB) and players of all positions were included. Player demographics, injury characteristics, surgical details, and postoperative outcomes were obtained. Player demographics included age at surgery, position of play, professional level of play and surgical technique. Outcomes assessed were return to play (RTP) status, time to RTP, return to same level of play (RTSL), time to RTSL, revision MUCL surgery, and time to revision MUCL surgery, with a minimum of 2 years of follow up. Players were considered to have RTP if they participated in at least one game at any professional level. RTSL was defined as returning to the same league of professional play or higher. Patients undergoing MUCL repair and "hybrid" MUCL reconstruction with internal bracing were independently compared to propensity matched patients undergoing isolated MUCL reconstruction, without internal bracing, to assess for a difference in postoperative outcomes. Four subgroup analyses were conducted by further categorizing patients to MLB players, MiLB players, pitchers, and position players. Results: 76 patients underwent MUCL repair with internal bracing from 2016-2021 and were successfully propensity matched to 76 patients undergoing isolated MUCL reconstructions. Baseline patient demographic variables of MUCL repairs were statistically similar to those of controls except for age at time of surgery (24.5 vs 21.8; p<0.001). 81 patients underwent "hybrid" MUCL reconstructions with internal bracing from 2016-2021 and were successfully propensity matched to 81 patients undergoing isolated MUCL reconstructions. Baseline demographic variables of "hybrid" MUCL reconstructions were statistically similar to those of controls except for age at time of surgery (24.3 vs. 23.3; p=0.006). Compared to isolated MUCL reconstruction controls, all patients undergoing MUCL repair demonstrated significantly shorter time to RTP (mean 421.2 vs. 546.2 days; p<0.001), shorter time to RTSL (mean 436.2 vs. 558.8 days; p<0.001), and shorter time to revision (mean 465.2 vs.1648 days; p=0.036). The number of patients who RTP at any level, RTSL, and number of revision surgeries were not significantly different. Compared to isolated MUCL reconstruction controls, all patients undergoing "hybrid" MUCL reconstructions demonstrated no significant differences with respect to the number of patients who RTP, time to RTP, number of patients who RTSL, days to RTSL, number of revision surgeries, and time to revision surgery. In MLB players only, compared to isolated MUCL reconstruction controls, patients who underwent MUCL repairs demonstrated significantly shorter time to RTP (mean 282.8 vs 507.3 days; p=0.008) and shorter time to RTSL (mean 299.7 vs. 598.0 days; p = 0.024). No other outcomes were significant. In MLB players only, compared to isolated MUCL reconstruction controls, patients who underwent "hybrid" MUCL reconstructions demonstrated significantly shorter time to RTP (mean 436.2 vs. 525.3 days; p=0.026). No other outcomes were significant. In MiLB players only, compared to isolated MUCL reconstruction controls, patients who underwent MUCL repairs demonstrated significantly shorter time to RTP (mean 444.3 vs 550.7 days; p<0.001) and shorter time to RTSL (mean 451.7 vs. 556.5 days; p<0.001). No other outcomes were significant. In MiLB players only, compared to isolated MUCL reconstruction controls, patients who underwent "hybrid" MUCL reconstructions demonstrated no significant differences in outcomes. In evaluating pitchers only, compared to isolated MUCL reconstruction controls, patients undergoing MUCL repair demonstrated significantly shorter time to RTP (mean 421.7 vs. 578.6 days; p<0.001), shorter time to RTSL (mean 434.8 vs. 591.6 days; p <0.001), and shorter time to revision surgery (mean 465.2 vs.1648 days; p=0.036). No other outcomes were significant. In pitchers only, compared to isolated MUCL reconstruction controls, patients undergoing "hybrid" MUCL reconstructions demonstrated significantly shorter time to RTP (mean 488.1 vs. 549.0 days; p=0.013) and shorter time to RTSL (mean 505.7 days vs. 577.0 days, respectively; p=0.021). No other outcomes were significant. Notably, all revision surgeries in occurred in pitchers only. Conclusions: Based on a matched cohort anaylsis of professional baseball players undergoing MUCL surgery, when compared to an isolated MUCL reconstruction, MUCL repair with internal bracing may allow for a shorter time to RTP and RTSL, with a shorter time to revision surgery. For pitchers, "hybrid" MUCL reconstruction may allow for a shorter time to RTP and RTSL. For MLB players, "hybrid" MUCL reconstruction may allow for a shorter RTP.
Poster 44: Outcomes of Revision Elbow Medial Ulnar Collateral Ligament Reconstruction in Professional Baseball Players: an Analysis of 191 Pitchers from 2010 to 2023
Chalmers, Peter N., Conte, Stan, Griffith, Timothy B. , Ma, Kevin , D’Angelo, John, Herbert, Liz, Simon, Karissa N. , Erickson, Brandon J. , Chalmers, Peter N. , Griffith, Timothy Bryan , D’Angelo, John, Herbert, Liz, Camp, Christopher L.

Orthopaedic Journal of Sports Medicine | September 26, 2025 | Volume: 13 | Issue: 9_suppl3 | Pages: No page available

10.1177/2325967125s00155 Get It

Objectives: The number of medial ulnar collateral ligament (MUCL) reconstructions are increasing. The epidemiology surrounding revision MUCL reconstructions in professional baseball players has not been well defined. The purpose of this study was to report the epidemiology of revision MUCL reconstruction in professional baseball players. The authors hypothesized that the number of revision MUCL reconstructions would increase over time and that the return to sport rate at the same level of play would be less than 70%. Methods: All professional baseball pitchers who underwent revision MUCL reconstruction between 2010-2023 were identified using the MLB Health and Injury Tracking System (HITS). Rate of return and time to return to play (RTP) and return to same level of play (RTSL) was recorded and analyzed for pitchers with a minimum follow up of 2 years. Surgical variables including technique and graft choice were also recorded. Results: Overall, 191 pitchers (avg age 26.0 years), underwent revision MUCL reconstruction. The average time between primary and revision surgery was 1,381 days (45 months). 130 (68%) of these players were MLB pitchers and the other 61 (32%) were MiLB pitchers. 59% of pitchers were able to RTSL at an average of 604 ± 250 days after surgery. 2023 was the year with most revision MUCL reconstructions (n = 27) and the fewest reconstructions were performed in 2010 and 2011 (n = 4). Monthly distribution demonstrates the highest surgery months to be May (17%), June (20%), and July (17%). Hamstring tendon autograft was found to be the most commonly used graft source (n = 90, 47%), compared to palmaris longus autograft (n = 67, 35%). No significant differences were found in the types of grafts used over time ( P = .238 for palmaris and P = .133 for hamstring). In terms of tunnel configuration, both the Modified Jobe and Docking techniques were used in equal occurrence (n = 70, 37%) Conclusions: Following revision MUCL reconstruction, only 72% of professional baseball pitchers were able to return to play at any level at an average of 556 days (18 months), and only 59% were able to return to the same level of play at an average of 604 days (20 months). The average time between primary and revision MUCL reconstruction was 45 months (3.75 years). Pitchers should be counseled on the relatively low RTSL rate and the prolonged time to RTSL.
Poster 52: Epidemiology of Ulnar Collateral Ligament Surgeries in Major and Minor League Baseball Pitchers: A Comprehensive Report of 2,287 Cases
Meta, Fabien , Meister, Keith, Griffith, Timothy B. , Chalmers, Peter N., Mavrommatis, Sophia , Griffith, Timothy Bryan , Chalmers, Peter N. , Clark, Sean C. , Camp, Christopher L.

Orthopaedic Journal of Sports Medicine | September 26, 2025 | Volume: 13 | Issue: 9_suppl3 | Pages: No page available

10.1177/2325967125s00163 Get It

Objectives: The medial ulnar collateral ligament (MUCL) is the primary stabilizer of valgus forces across the elbow. Injury to the MUCL has a large impact on the throwing athlete, particularly in baseball. The incidence of MUCL injury in baseball pitchers is on the rise. Surgical treatment and rehabilitation is evolving to improve outcomes and improve return to sport time frames. The purpose of this study was to highlight the trends in MUCL repair and reconstruction in professional baseball pitchers, describe relevant outcomes such as return to any level of play (RTP) for surgical repair and reconstruction, and distinguish what factors might impact these outcomes. The authors hypothesize that primary and revision MUCL surgery is increasing with revision surgery requiring the greatest time to RTP. Methods: The Major League Baseball (MLB) Health and Injury Tracking System (MLB HITS) database was used to procure data during the targeted study period (2010 – 2023). All professional pitchers who underwent MUCL surgery within the study period were included. Variables analyzed included age, career length, and level of play. Surgical variables included date and type of procedure, RTP status, time required to RTP, return to same level of play (RTSL), career length before and after surgery, number of revision surgeries, and time between surgeries. Successful RTP was designated if a pitcher had returned in at least one professional game after index surgery. Analyses of trends over time were performed. The year 2020 was considered an outlier and omitted from the analysis of trends due to the coronavirus pandemic which limited games played. Results: A total of 2,287 pitchers underwent MUCL surgery during the study period (Table 1). The annual number of MUCL surgeries on all pitchers increased year over year (R 2 = 0.821, p < 0.001), as did the annual number of reconstructions with internal brace (IB) augmentation (R 2 = 0.896, p < 0.001) (Figure 1). The RTP rate (93%) for MLB pitchers was significantly higher compared to the RTSL rate (71%, P < 0.001). This difference was not observed in Minor League Baseball (MiLB) (RTP 76% vs. RTSL 74%, P = 0.142) (Figure 2). The percentage of players who RTP after revision surgery was significantly lower compared to primary surgery (71%vs. 80% respectively, P = 0.020). Mean time to RTP is significantly shorter (470 ± 135 days) compared to the mean time to RTSL (499 ± 153 days, P < 0.001) (Figure 3). The annual number of revision MUCL surgeries on all pitchers increased year over year as well (R 2 = 0.322, p = 0.043). Conclusions: MUCL surgery continues to increase, also leading to increasing numbers of revisions in professional pitchers. Overall, 80% of pitchers were able to RTP at a mean of 470 days (15.5 months), while only 71% were able to RTSL at a mean of 499 days (16.5 months), but this varied based on level of play. Surgical techniques continue to evolve as MUCL repairs and reconstructions with IB augmentation have increased significantly in recent years. This study will help guide athlete expectations and surgeon decision-making.
Epidemiology of Elbow Medial Ulnar Collateral Ligament Surgeries in Major and Minor League Baseball Pitchers: A Descriptive Study of 2281 Cases
Meta, Fabien , Meister, Keith, Griffith, Timothy B. , Conte, Stan, Chalmers, Peter N., Mavrommatis, Sophia , Hebert, Elizabeth, Clark, Sean C. , Griffith, Timothy Bryan , Chalmers, Peter N. , Hebert, Elizabeth, Camp, Christopher L.

Orthopaedic Journal of Sports Medicine | July 7, 2025 | Volume: 13 | Issue: 7 | Pages: No page available

10.1177/23259671251352199 Get It

Background: Injuries of the medial ulnar collateral ligament (MUCL) among baseball pitchers are increasing. Surgical treatment is evolving to optimize outcomes. Purpose/Hypothesis: This study’s purpose was to highlight trends in MUCL repair and reconstruction in professional pitchers, describe outcomes such as return to any level of play (RTP), and identify factors impacting these outcomes. It was hypothesized that primary and revision MUCL surgery is increasing, with revision surgery requiring greater RTP time. Study Design: Case series; Level of evidence, 4. Methods: The Major League Baseball (MLB) Health and Injury Tracking System database was used to procure data during the study period (2010-2023). All professional pitchers who underwent MUCL surgery during this period were included. RTP was defined as a pitcher returning to at least 1 professional game after index surgery. Return to the same level of play (RTSL) was defined as return to at least 1 game in the same league of play as before surgery. Because of the coronavirus pandemic, the year 2020 was considered an outlier and omitted from time-trend analysis. Results: A total of 2281 pitchers who underwent MUCL surgery during the study period were included for analysis. The number of MUCL surgeries for pitchers increased yearly ( R 2 = 0.821; P < .001), as did the number of reconstructions with internal brace augmentation ( R 2 = 0.896; P < .001). The RTP rate for MLB pitchers was significantly higher than the RTSL rate (93% vs 71%; P < .001). This difference was not observed in Minor League Baseball (MiLB) pitchers (RTP 76% vs RTSL 74%; P = .142). RTP rates after revision surgery were lower than those after primary surgery (71% vs 80%; P = .020). The mean time to RTP was shorter (470 ± 135 days) than the mean time to RTSL (499 ± 153 days; P < .001). Conclusion: The incidence of MUCL surgery and revision surgery is increasing among professional pitchers. Overall, 79% of pitchers returned to any level of play at a mean of 470 days, while 74% returned to the same level of play at a mean of 499 days, but this varied based on level of play. This study will guide athlete expectations and surgeon decision-making.
Musculoskeletal Findings of the Major League Baseball Combine: A Description of the “Normal” Prospective Professional Baseball Player
Erickson, Brandon J. , D’Angelo, John , Ma, Kevin , Casey, Helen, Papp, Derek F. , Lund, Pamela, Chalmers, Peter N. , Camp, Christopher L. , Chalmers, Peter N , Hebert, Liz, Potter, Hollis G.

The American Journal of Sports Medicine | May 19, 2025 | Volume: 53 | Issue: 8 | Pages: 1826-1831

10.1177/03635465251339773 Get It

Background: Major League Baseball (MLB) recently instituted a combine for their prospective players. Purpose/Hypothesis: The purpose of this study was to report initial epidemiological findings for both physical examination and imaging findings for the MLB Combine. It was hypothesized that most players would have no significant abnormal physical examination findings, but most would have abnormal findings on their shoulder and elbow magnetic resonance imaging (MRI) scans. Study Design: Descriptive epidemiology study. Methods: All players who attended the 2023 MLB Combine were included. History was taken and physical examination was performed by an MLB team physician, and MRI of the shoulder, elbow, cervical spine, and lumbar spine was performed on all players and read by 1 of 2 musculoskeletal radiologists. Physical examination notes and imaging reports were reviewed by the authors and recorded. Data were analyzed separately for pitchers and position players. Results: Overall, 219 players (112 pitchers [51%], 107 position players [49%]) were included. The mean age was 20.4 ± 1.5 years. The majority of players (95%) had no current pain or limitations; 54 players (25%) had a history of previous surgery. For pitchers, 18% underwent previous elbow surgery. With regard to MRI, >80% of pitchers had some abnormality within their ulnar collateral ligament (UCL), the majority of which was UCL scarring/remodeling. 70% of pitchers and 60% of position players had evidence of an olecranon osteophyte. Increased signal within the ulnar nerve was common in pitchers (40%) but rare in position players (4%). For the shoulder, 95% of pitchers and 93% of position players had some rotator cuff abnormality (often tendinosis within the supraspinatus and infraspinatus muscles). Also, 75% of pitchers had MRI evidence of a superior labrum anterior to posterior (SLAP) tear, while 24% of position players demonstrated this. Lumbar spine MRI showed that 47% of position players had a disk protrusion and 46% had a previous pars fracture. Conclusion: Most baseball players who participated in the 2023 MLB Combine had MRI evidence of rotator cuff abnormalities, and many showed evidence of an olecranon osteophyte. Eighteen percent of pitchers had a previous history of elbow surgery. The majority of pitchers had some abnormality within their UCL and evidence of a SLAP tear on MRI scans.
Outcomes of Revision Elbow Medial Ulnar Collateral Ligament Reconstruction in Professional Baseball Players: An Analysis of 191 Pitchers From 2010 to 2023
Erickson, Brandon J. , Chalmers, Peter N. , Griffith, Timothy B. , Simon, Karissa N. , Hebert, Elizabeth, Meister, Keith, Camp, Christopher L. , Chalmers, Peter N , Griffith, Timothy Bryan , Hebert, Elizabeth

The American Journal of Sports Medicine | March 4, 2025 | Volume: 53 | Issue: 5 | Pages: 1210-1215

10.1177/03635465251322780 Get It

Background: The number of medial ulnar collateral ligament (MUCL) reconstructions is increasing. The epidemiology surrounding revision MUCL reconstructions in professional baseball players has not been well defined. Purpose/Hypothesis: The purpose was to report the epidemiology of revision MUCL reconstruction in professional baseball players. The authors hypothesized that the number of revision MUCL reconstructions has increased over time and that the rate of return to sport at the same level of play is <70%. Study Design: Case series; Level of evidence, 4. Methods: All professional baseball pitchers who underwent revision MUCL reconstruction between 2010 and 2023 were identified using the Major League Baseball Health and Injury Tracking System. Rates of return to play, time to return to play, and return to same level of play were recorded and analyzed for pitchers with a minimum follow-up of 2 years. Surgical variables, including technique and graft choice, were also recorded. Results: Overall 191 pitchers (mean age, 26.0 years) underwent revision MUCL reconstruction. The mean time between primary and revision surgery was 1381 days (45 months). Of these players, 130 (68%) were Minor League Baseball pitchers. Hamstring tendon autograft was the most commonly used graft source (n = 90; 47%) when compared with palmaris longus autograft (n = 67; 35%). In terms of tunnel configuration, the modified Jobe and docking techniques were used in equal occurrence (n = 70; 37%). After revision MUCL reconstruction, only 72% of professional baseball pitchers were able to return to play at any level at a mean 556 days (18 months), and only 58% were able to return to the same level of play at a mean 604 days (20 months). The mean time between primary and revision MUCL reconstruction was 45 months (3.75 years). Conclusion: Revision MUCL surgery continues to be a challenging problem, where the procedure is complex, rehabilitation timelines are prolonged, and outcomes are not always optimal. Accordingly, the authors recommend that these procedures be performed by surgeons with high levels of experience.
Interval Throwing Programs for Baseball Players: Methodological Assessment of the Quality and Construct of Publicly Available Programs
Boos, Alexander M. , Sambare, Namit, Smith, Matthew V. , Freehill, Michael T. , Bowman, Eric N. , Erickson, Brandon J. , Chalmers, Peter N. , Sciascia, Aaron , Camp, Christopher L. , Sciascia, Aaron D. , Camp, Christopher L. , Boos, Alexander , Freehill, Michael T

Sports Health: A Multidisciplinary Approach | March 28, 2024 | Volume: 17 | Issue: 3 | Pages: 451-459

10.1177/19417381241237011 Get It

Context: The quality and interprogram variability of publicly available throwing programs have not been assessed. Objective: To (1) identify publicly available interval throwing programs, (2) describe their components and structure, and (3) evaluate their quality, variability, and completeness. Data Sources: Google, Bing, Yahoo; keyword: “interval throwing program.” Study Selection: Baseball-specific publicly available programs. Study Design: Systematic review. Level of Evidence: Level 4. Data Extraction: Independent evaluation by 2 authors using a novel 21-item Quality Assessment Rubric (QAR). Results: Of the 99 included programs, 54% were designed for return from injury/surgery; 42% explicitly stated no expected timeline for completion, and approximately 40% did not provide criteria to initiate the program. Program construction was highly variable. There were broad-ranging shortest (mean: 40±8 ft, range: 20-45 ft) and longest (mean: 150±33 ft, range: 90-250 ft) long toss distances, and variable maximum numbers of mound pitches thrown before returning to game play (range: 40-120, mean: 85). Only 63% of programs provided guidelines for handling setbacks, and standardized warm-ups, arm care, and concomitant training were absent in 32%, 63%, and 47% of programs, respectively. Mean QAR completion rate and QAR item response rate were low (62 ± 4% [range, 24-91%], 62 ± 24% [range, 7-99%], respectively). Finally, only 20 (20%) programs provided at least 1 peer-reviewed reference, most of which were published >10 years ago. Conclusion: Publicly available interval throwing programs are readily available but demonstrate significant interprogram heterogeneity across multiple areas including target audience, program construction, progression, and execution. The quality and consistency of publicly available interval throwing programs is poor at this time, which may limit their utility and effectiveness for baseball players attempting to return to competition. This work identifies a multitude of deficiencies in currently available throwing programs that should be targets of future improvement efforts.
Characteristics Associated With Noncompliance of Current Pitch Smart Guidelines in High School Baseball Pitchers Throughout the United States
Bowman, Eric N. , Smith, Matthew V. , Serio, Nicholas, Ishikawa, Hiroaki , Smith, Karch, Chalmers, Peter N. , Camp, Christopher, Erickson, Brandon J. , Camp, Christopher L. , Freehill, Michael T.

Orthopaedic Journal of Sports Medicine | September 26, 2023 | Volume: 11 | Issue: 9 | Pages: No page available

10.1177/23259671231199085 Get It

Background: Although pitch count and rest guidelines have been promoted for youth and adolescent baseball players for nearly 2 decades, compliance with guidelines remains poorly understood. Purpose/Hypothesis: The purpose of this study was to determine the frequency of compliance with Major League Baseball (MLB) Pitch Smart guidelines as well as the association between compliance and range of motion (ROM), strength, velocity, injury, and pitcher utilization. It was hypothesized that pitchers in violation of current recommendations would have increased strength, velocity, and injury. Study Design: Case-control study; Level of evidence, 3. Methods: This was a prospective, multicenter study of 115 high school pitchers throughout the United States. Pitchers were surveyed about their compliance with current off-season, rest-related guidelines, and history of injury. During the preseason, pitchers underwent standardized physical examinations, and pitch velocity was measured. Pitch counts were collected during the baseball season that followed. Dynamometer strength testing of shoulder forward flexion, and external rotation as well as grip strength was recorded. We compared pitchers who were compliant with recommendations with those who were noncompliant using Student t and Mann-Whitney U tests. Results: Based on preseason data, 84% of pitchers had violated current Pitch Smart guidelines. During the season, 14% had at least 1 violation of the Pitch Smart guidelines. Across both the preseason survey and in-season pitch counts, 89% of players had at least 1 violation of the Pitch Smart guidelines. While there were no significant differences in ROM or strength, the noncompliant group had higher maximum pitch velocity than the compliant group (74 ± 8 vs 69 ± 5 mph [119 ± 13 vs 111 ± 8 kph], respectively; P = .009). Players’ self-reported velocity differed significantly from the direct measurement, for both peak velocity (80 ± 6 vs 73 ± 8 mph [129 ± 9 vs 117 ± 13 kph], respectively; P < .001) and mean velocity (73 ± 8 vs 53 ± 27 mph [117 ± 13 vs 85 ± 43 kph], respectively; P < .001). Conclusion: Most high school pitchers were not fully compliant with current Pitch Smart guidelines, and they tended to overestimate their peak velocity by 7 mph (11 kph). Pitchers who threw with greater velocity were at higher risk for violating Pitch Smart recommendations.
Poster 206: What are the Indications for Medial Ulnar Collateral Ligament Surgery in Baseball Players? An MRI Case-based Study
Smith, Matthew V. , Chalmers, Peter N. , Freehill, Michael T. , Camp, Christopher L. , Erickson, Brandon J. , Sciascia, Aaron , Silva, Adrik Z. Da , Bowman, Eric N.

Orthopaedic Journal of Sports Medicine | July 31, 2023 | Volume: 11 | Issue: 7_suppl3 | Pages: No page available

10.1177/2325967123s00191 Get It

Objectives: Ulnar Collateral Ligament (UCL) tears are common in baseball players. When non-operative management fails; reconstruction or repair may be necessary to restore physical function. There is no clear consensus regarding the indications for surgery based on magnetic resonance imaging (MRI) tear characteristics, or the indications for selecting repair over reconstruction. The purpose of this study was to define the indications for UCL surgery based on MRI and to elucidate indications for UCL repair vs reconstruction. Methods: Twenty-six orthopaedic surgeons who treat baseball players were surveyed. Forty-five MRIs were reviewed: 15 without UCL tears, 15 with intra-operatively confirmed partial-thickness tears, and 15 with full-thickness tears. Factors investigated included ligament characteristics (peri-ligamentous or osseous edema, ligament hypertrophy, calcification, partial or full-thickness tearing) and location (proximal, mid-substance, or distal). Surgeons were given a clinical scenario and asked whether 1) surgery was indicated and 2) whether repair or reconstruction was recommended. Odds ratios (OR) and 95% confidence intervals (95%CI) helped identify significant predictors for both queries. Results: The odds of recommending surgical treatment compared to non-operative treatment were 2.4x more likely for a proximal partial-thickness tear, 3.2x for distal partial-thickness tear, 5.1x for distal full- thickness tear, and 7.0x for proximal full-thickness tear (p<0.001). Significant indications for repair included distal partial (OR=1.6, 95%CI 1.0, 2.1, p<0.001) and full-thickness tears (OR=1.7, 95%CI 1.1, 2.3, p<0.001). Repair was 3x less likely recommended for mid-substance full-thickness tears (OR=3.0, 95%CI - 5.0, -1.0, p=0.004). Ultrasound stress testing was requested in 78% of partial tears. Conclusions: Among surgeons surveyed, the highest odds for recommending operative treatment were proximal full-thickness tears, then distal full-thickness, distal partial-thickness, and proximal partial- thickness tears. Repair was most appropriate for partial and full-thickness distal tears, but relatively contraindicated for complete mid-substance UCL tears. Ultrasound stress testing was frequently requested for partial tears. Given the lack of consensus among surgeons, future prospective registries are necessary to determine whether these factors associate with clinical outcomes. [Table: see text]