Hamstring intramuscular tendon injury RTP decision-making: Does a picture speak 1000 words?
2016 Rio Olympics – Soccer – Preliminary – Women’s First Round – Group E Brazil v Sweden – Olympic Stadium – Rio de Janeiro, Brazil – 06/08/2016. Cristiane (BRA) of Brazil reacts after an injury. REUTERS/Gonzalo Fuentes
Paper title: Complete resolution of a hamstring intramuscular tendon injury on MRI is not necessary for a clinically successful return to play.
Publication: British Journal of Sports Medicine 2021;55:397-402.
Publication date: April 2021.
Hamstring injuries make up a significant percentage of acute, sports-related musculoskeletal injuries. There is ongoing debate regarding the return to play (RTP) decision-making criteria. The involvement of the intramuscular tendon delays RTP and is a risk factor for re-injury. The clinical assessment and differentiation of intramuscular tendon involvement are challenging, and thus clinicians utilize magnetic resonance imaging (MRI) to confirm the degree and prognosis of the injury. However, the significance of MRI in RTP decision-making is questionable as edema and fibrosis remain present following successful RTP. This study aimed to describe the MRI characteristics at RTP, evaluate healing, and examine the relationship between MRI characteristics at RTP with re-injury for clinically recovered hamstring intramuscular tendon injuries.
Investigators used a combined cohort of two double-blind, placebo-controlled randomized controlled clinical trials (RCT). Investigators included 41 participants from both studies with a confirmed hamstring intramuscular tendon injury on MRI at baseline (within five days of injury) and RTP (within seven days of RTP). On MRI, intramuscular tendon injury is characterized by a loss of low signal intensity within the tendon, with or without waviness.
In both groups, investigators assessed the re-injury rates up to one year through regular phone contact with participants. A subset of participants received a platelet-rich plasma (PRP), platelet-poor plasma injection, or saline (placebo) injection in both RCTs. In addition, all participants underwent standardized rehabilitation for their injury, supervised by sports physiotherapists.
RESULTS AND CLINICAL IMPLICATIONS
Throughout both studies, the MRI characteristics of clinically recovered injuries changed, signifying the presence of tissue healing. Over half of the participants still displayed partial or complete tendon discontinuity despite clinically successful RTP. Investigators found no difference in re-injury rates between those with or without intramuscular tendon involvements at RTP.
An MRI remains a costly investigation, and although it may assist in the diagnosis and prognosis of hamstring injuries, its relevance in RTP decision-making is questionable. To clear athletes for RTP, complete resolution on MRI is unnecessary. The presence of tissue changes on MRI may impact an athlete’s psychological readiness despite the apparent clinical insignificance. Clinicians should base RTP decision-making on a comprehensive physical and field-based assessment.