High-grade intramuscular tendon disruption in acute hamstring injury and return to play in Australian Football players.

BACKGROUND

Recent literature has reported intramuscular tendon (IT) disruption is associated with longer return to play (RTP) following acute hamstring injury.

OBJECTIVES

Investigate whether an increase in hamstring injury severity involving high-grade IT disruption and proximal injury location is associated with longer RTP times in elite Australian Rules Football (AFL) players.

METHODS

Hamstring injury records and RTP times from one professional AFL club were obtained over six seasons. MRI of injuries was retrospectively reviewed by a musculo-skeletal radiologist blinded to RTP information. A simplified four-grade classification of acute hamstring injuries was developed based on IT disruption severity and proximodistal injury location. MR0 had no observable MRI tissue damage; MR1 involved muscle-tendon junction, myofascial and low-grade IT injuries; MR2 involved distal and/or single muscle high-grade IT injuries, and MR3 involved high-grade IT injuries of the proximal biceps femoris (BF) IT with concomitant injury to BF+ semitendinosus muscles.

RESULTS

Forty-one injuries were available for analysis. Median RTP times were as follows: MR0, 14 days; MR1, 21 days; MR2, 35 days; and MR3, 88 days. For MRI-positive injuries (MR1, MR2, MR3), there was a significant difference in the distributions of RTP, with increased injury severity associated with increased RTP times (P < .001). The distributions of RTP were significantly different between MR1 vs MR2 (P = .008), MR1 vs MR3 (P = .002), and MR2 vs MR3 (P = .012).

CONCLUSION

In elite AFL players, acute hamstring injuries with high-grade IT disruption identified on MRI were associated with increased times to RTP compared to injuries with low-grade or no IT disruption.