Complete resolution of a hamstring intramuscular tendon injury on MRI is not necessary for a clinically successful return to play

Abstract

BackgroundClinical decision-making around intramuscular tendon injuries of the hamstrings is a controversial topic in sports medicine. For this injury, MRI at return to play (RTP) might improve RTP decision-making; however, no studies have investigated this.ObjectiveOur objectives were to describe MRI characteristics at RTP, to evaluate healing and to examine the association of MRI characteristics at RTP with reinjury for clinically recovered hamstring intramuscular tendon injuries.MethodsWe included 41 athletes with hamstring intramuscular tendon injuries and an MRI at baseline and RTP. For both MRIs, we used a standardised scoring form that included intramuscular tendon injury characteristics. We recorded reinjuries during 1-year follow-up.ResultsAt RTP, 56% of the intramuscular tendons showed a partial or complete thickness tendon discontinuity. Regarding healing from injury to RTP, 18 of 34 (44% overall) partial-thickness tendon discontinuities became continuous and 6 out of 7 (15% overall) complete thickness tendon discontinuities became partial-thickness tendon discontinuities. Waviness decreased from 61% to 12%, and 88% of tendons became thickened. We recorded eight (20%) reinjuries within 1 year. Intramuscular tendon characteristics at RTP between participants with or without a reinjury were similar.ConclusionComplete resolution of an intramuscular tendon injury on MRI is not necessary for clinically successful RTP. From injury to RTP, the intramuscular tendon displayed signs of healing. Intramuscular tendon characteristics of those with or without a reinjury were similar.

Return to Play After a Hamstring Strain Injury: It is Time to Consider Natural Healing

“…Namely, is a complete and thus terminated muscle healing necessary for a successful RTP? According to a previous study of Vermeulen et al [35], this does not seem to be the case. First, it should be mentioned that the study of Vermeulen et al agrees with the previously stated fact that at the moment of RTP (the moment that the athlete seems clinically recovered), MRI does not depict a complete resolution of the hamstring injury [32,35].…”

“…According to a previous study of Vermeulen et al [35], this does not seem to be the case. First, it should be mentioned that the study of Vermeulen et al agrees with the previously stated fact that at the moment of RTP (the moment that the athlete seems clinically recovered), MRI does not depict a complete resolution of the hamstring injury [32,35]. However, the authors reported that the group of athletes that obtained a reinjury showed the same tissue discontinuities on MRI as the group of athletes that had a successful, (re)injury-free RTP [35].…”

Hamstring Strain Injury Rehabilitation

“…Athletes can, however, successfully RTS despite persistent signs of intramuscular tendon disruption on follow-up MRI, without increasing their risk of re-injury. 34 Based on current evidence, practitioners with scope to refer for an MRI may be able to provide a more accurate prognosis for RTS by differentiating between HSIs with and without visible tissue damage or proximal tendon involvement. However, the need to alter rehabilitation and RTS decision-making based purely on other MRI findings, such as intramuscular tendon disruption, requires further investigation before being recommended as standard practice.…”

“…Deficits in hamstring muscle structure and function are commonly observed at the time of RTS or even later following HSI, 42,60 but there is little evidence to suggest these variables are associated with re-injury. When measured at RTS, risk of re-injury is increased with greater between-leg deficits in active knee extension ROM and isometric hamstring strength, 47 but unaltered by residual deficits on MRI 34 or isokinetic strength testing. 60 These findings are limited to relatively small sample sizes, highlighting the need to conduct multi-site studies, employing a standard suite of RTS assessments, over several years, to identify variables associated with re-injury risk.…”

Differentiation Between Tendinous, Myotendinous and Myofascial Injuries by L-BIA in Professional Football Players

“…And when an injury in the myoconnective junction has a tendon gap (by MRI), the injury will have worst prognosis, require longer time to RTP and could present greater risk of re-injury compared to others injuries. However, a study of full-thickness intramuscular tendon damage, did not show re-injury after 12 months ( Vermeulen et al, 2019 ). Regarding MTJ and MFJ injuries, it is not clear which one has better prognosis and, consequently, less time to RTP ( Balius et al, 2020 ).…”