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

Abstract

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.

Use of an Elbow Brace During Repetitive Pitching Does Not Cause an Increased Mechanical Burden on the Throwing Arm

“…Further studies as to whether the use of the elbow brace causes injury to other parts of the body are also necessary. As shown in the prior study, the elbow brace used in this study was uncomfortable during throwing, so it may be necessary to improve the elbow brace by reducing its weight and improving material comfort. If these further studies and improvements in elbow braces develop, we may be able to recommend that adolescent baseball pitchers use an elbow brace during training and games.…”

“…We previously reported the data on the medial elbow joint space gapping when participants were using an elbow brace during repetitive pithing in order to reduce the mechanical burden on the elbow joint . This previous study has shown that use of an elbow brace during repetitive pitching prevents an increase in the medial elbow joint space gapping without influencing pitching performance, suggesting the possibility that the use of the elbow brace may be effective in the prevention of medial elbow injury.…”

“…If these further studies and improvements in elbow braces develop, we may be able to recommend that adolescent baseball pitchers use an elbow brace during training and games. In particular, future studies can identify whether a brace can limit the burden on the medial elbow joint such as on resumption of throwing after UCL injury or after UCL reconstruction surgery, and when repetitive pitching of more than 60 pitches, which results in an expected increase in medial elbow joint space gapping …”

“…This study investigated the burden on the throwing arm resulting from pitching without an elbow brace compared with pitching with an elbow brace. The throwing protocol was reported in a previous study . Measurement commenced after the participants performed a preparation routine of stretching and warm‐up throwing.…”

“…Grip strength of the throwing arm was measured using a grip strength dynamometer (GRIP‐D T.K.K.5401; Takei Scientific Instruments Co., Ltd., Niigata, Japan) before pitching and after 100 pitches. The mean of three trials was used for data analysis …”