Muscle Injuries in Sports: A New Evidence-Informed and Expert Consensus-Based Classification with Clinical Application

Abstract

Muscle injuries are among the most common injuries in sport and continue to be a major concern because of training and competition time loss, challenging decision making regarding treatment and return to sport, and a relatively high recurrence rate. An adequate classification of muscle injury is essential for a full understanding of the injury and to optimize its management and return-to-play process. The ongoing failure to establish a classification system with broad acceptance has resulted from factors such as limited clinical applicability, and the inclusion of subjective findings and ambiguous terminology. The purpose of this article was to describe a classification system for muscle injuries with easy clinical application, adequate grouping of injuries with similar functional impairment, and potential prognostic value. This evidence-informed and expert consensus-based classification system for muscle injuries is based on a four-letter initialism system: MLG-R, respectively referring to the mechanism of injury (M), location of injury (L), grading of severity (G), and number of muscle re-injuries (R). The goal of the classification is to enhance communication between healthcare and sports-related professionals and facilitate rehabilitation and return-to-play decision making.

Calf muscle strain injuries in elite Australian Football players: A descriptive epidemiological evaluation

“…The absence of an inciting incident might be related to the precise anatomical location of injury and/or severity of tissue disruption, such as whether the injury primarily involves the epimysial layer versus injuries involving the intramuscular aponeuroses. 16,17 Clearly, further research is warranted to explore whether the mechanism of injury is associated with specific injury characteristics.…”

“…13,15,16 Furthermore, clinical factors at baseline may explain some of the variation in the time taken to return to play (RTP), but the prognostic value of clinical factors for estimating recovery following CMSI requires further investigation. 17 It is likely that intrinsic factors, such as strength, flexibility, and functional capacity, as well as extrinsic factors, such as the stage of the season, the mechanism of injury, and whether it is a first time injury or a re-injury, [17][18][19] play a role in the time that it takes to achieve recovery milestones and RTP following CMSI. It has not been possible to determine the impact of these factors from research to date since direct references to prognostic data and information regarding the characteristics of the injured athletes or the circumstances of injury are often lacking.…”

MR Imaging of Muscle Trauma: Anatomy, Biomechanics, Pathophysiology, and Imaging Appearance

“…There may be accompanying injury to the subcutaneous tissues, fascia, and/or bone (18,41). While contusions often appear larger than strain injuries, fiber disruption is primarily limited to muscle, which heals faster than tendon, so the recovery time after contusions tends to be shorter than that after strains (2,28). In one large study evaluating thigh injuries in professional soccer players, contusions resulted in half the time lost to sport as compared with strains (41,42).…”

“…ISMuLT) and subclassifies indirect injuries by area involved and specific tissues injured (similar to British Athletics) (28,84). This system additionally stratifies strain into initial injury or reinjury at a site of prior tissue damage, reflecting the average 30% longer recovery time for reinjury at sites of preexisting tissue damage (28,84) (Fig 39).…”

“…This system additionally stratifies strain into initial injury or reinjury at a site of prior tissue damage, reflecting the average 30% longer recovery time for reinjury at sites of preexisting tissue damage (28,84) (Fig 39). Early studies assessing the utility of these comprehensive systems suggest that classifications incorporating mechanism, clinical assessment, and imaging findings reflecting the precise location and extent of injury improve prognostic accuracy (83,85).…”