BICEPS FEMORIS MUSCLE ARCHITECTURE – THE INFLUENCE OF PREVIOUS INJURY. Issue 7 (11th March 2014)

• Record Type: Journal Article
• Authors: Timmins, R; Porter, K; Williams, M; Shield, A; Opar, D
• Is Part Of: British journal of sports medicine. Volume 48:Issue 7(2014)
• Page Start: 665
• Page End: 666
• Publication Date: 2014-03-11
• Subjects: Sports medicine -- Periodicals; 617.1027
• DOI: 10.1136/bjsports-2014-093494.282
• Languages: English
• ISSNs: 0306-3674

Abstract

Abstract : Background: A history of hamstring strain injury (HSI) has been indicated as a primary risk factor for a future injury. It is unknown whether a prior strain influences the architectural characteristics of the hamstring. Objective: To determine if alterations occur to the architecture of the long head (BFlh) muscle in those with a history of strain injury to this muscle. Design: Reliability and retrospective case-control study design. Setting: Clinical setting with recreationally active males and elite Australian Footballers. Participants: 31 males (Australian Footballers n=14, recreational males n=17). Of the 31 participants, 18 had a prior unilateral HSI, whereas the other 13 formed an uninjured control group. Risk factor assessment: The independent variables were muscle fascicle length (FL), pennation angle (PA) and thickness (MT)). Main outcome measure: The BFlh muscle architecture of both limbs was assessed utilising B-mode ultrasound (General Electric Vivid-i) whilst rested in a prone position. The scan site was determined as 50% of the distance between the ischial tuberosity and the lateral knee joint line. The hypothesis prior to recruitment was that a history of injury would result in a reduction of FL and MT and an increase in PA. Reliability was assessed at a second time point within ten days of the initial visit and was determined utilising intra-class correlations (ICC). Results: The assessment of the architectural characteristics of the BFlh was shown as reliable whilst in a rested state (FL and PA ICC=0.97, MT=0.96). PA's (P=.001) and FL's (P=.013) were significantly less in the previously injured BFlh then the contralateral uninjured limb. Muscle thickness was not significantly different (p=0.466). Conclusions: Ultrasound is a reliable measure of architectural characteristics in the BFlh. A previously injured BFlh displays reductions in FL and increases in PA. These variations may partly explain the high rate of recurrence of HSI's.