Do anatomic changes found in the throwing arm after a season of pitching resolve with off-season rest? A dynamic ultrasound study

Abstract

HypothesisOur hypothesis was that seasonal adaptive changes in the ulnar collateral ligament (UCL), ulnohumeral joint space (UHJS), and glenohumeral internal rotation deficit (GIRD) of the pitching extremity would subsequently resolve with off-season rest.MethodsEleven collegiate pitchers underwent preseason, postseason, and off-season evaluations including physical examination; dynamic ultrasound imaging of the UCL and UHJS; and the short version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire. Ultrasound images were evaluated by 2 fellowship-trained musculoskeletal radiologists.ResultsAll 11 pitchers were included in the final analysis, with an average age of 20.1 years and with 14.1 years of playing experience. After a season of pitching, we found significant increases in GIRD (P = .004) and UCL thickness (P = .033) and nonsignificant increases in both unloaded (P = .069) and loaded (P = .122) UHJS. Preseason GIRD correlated with this increase in loaded UHJS (r = 0.80, P = .003). The increase in UCL thickness was significantly greater in pitchers with GIRD greater than 10° (P < .05). After the off-season, UCL thickness returned to baseline and significant decreases were noted in both unloaded (P = .004) and loaded (P = .041) UHJS, but a progression in GIRD was found (P = .021). Pitchers with GIRD of 10° or less showed greater improvement in UHJS after the off-season (P < .05).ConclusionsThe pitching season produced adaptive changes in the throwing elbow that subsequently resolved after off-season rest. However, shoulder range-of-motion deficits were progressive and did not resolve. Ultrasound adaptations of the pitching elbow were significantly related to GIRD.

Elbow Torque May be Predictive of Anatomic Adaptations to the Elbow After a Season of Collegiate Pitching: A Dynamic Ultrasound Study

“…32,33 Previous literature has suggested that increased elbow stresses in overhead throwing athletes may lead to ulnohumeral adaptive changes on ultrasound, as demonstrated in this study, such as UCL thickening. 14,18,25,30 In a cross-sectional study of 102 pitchers, Atanda et al 14 ELBOW TORQUE AND POSTSEASON US CHANGES e5 adolescent pitchers and found that the UCL was significantly thicker in pitchers who threw more than 67 pitches per appearance (4.69 mm vs 4.14 mm, P ¼ .03). In a prospective observational study of 22 high school pitchers, Keller et al 18 found significant increases in UCL thickness and UCL substance heterogeneity (P ¼ .02 and P ¼ .001) after a season of pitching relative to preseason measurements.…”

“…Anthropometric and arm length measurements in this study were consistent with previous studies implementing this wearable device. 5,6,24,25 Pitchers were fitted with an appropriately size athletic sleeve containing a medial elbow sensor, which recorded accelerometer and gyroscope data to a mobile phone application (motusTHROW v 8.3.3; Motus Global, Seattle, WA). The device manufacturer and vendor had no involvement in funding or design of this study.…”

“…[4][5][6]8,[26][27][28] Consistent with previous literature, preseason data were collected within 2 weeks of the first game of the season and postseason data were collected within 1 week of the final game. 18,25 For each session, testing while using the wearable sensor technology compression sleeve followed a similar format to prior studies. 5,6,23,28,29 Participants were allowed as much time as they required to warm up using their typical routine.…”

“…Studies conducting serial ultrasound imaging have demonstrated that UCL thickness and UHJS widening progress after a season of pitching. 16,18,25,32 Tajika et al 33 evaluated 122 high school baseball pitchers during the preseason with ultrasound of their dominant elbow and found significantly greater UCL thickness and UHJS widening in pitchers with a history of elbow pain. Furthermore, Shanley et al 32 performed dynamic ultrasounds on 70 asymptomatic professional baseball pitchers, following these pitchers prospectively, and discovered that the 7 pitchers who subsequently sustained a UCL injury had significantly greater elbow laxity than the 63 who remained healthy (6.5 AE 1.2 vs 5.3 AE 1.2 mm, P ¼ .01).…”

Effect of Fascial Manipulation on Glenohumeral Internal Rotation Deficit in Overhead Athletes - A Randomized Controlled Trial

“…Even though anatomic changes in the ulnar collateral ligaments of the elbow have shown some potential to resolve during off-season, GIRD which had developed during the competitive season, were found to progress and did not resolve even after off-season rest. Since there is a plausible association between the UCL adaptations and GIRD and the progressive adaptations of GIRD in OTA, it is vital to improve GIRD to reduce the risk of shoulder and elbow injuries in OTA (8). Joint mobilization, shoulder capsular release using balls, and stretching of the posterior capsule are the conventional treatment strategies used in the management for GIRD (3,6).…”