Active Voluntary Contraction of the Ruptured Muscle Tendon during the Wide-awake Tendon Reconstruction

PURPOSE: The purpose of this study was to measure the active voluntary contraction distances of ruptured musculotendinous units during wide-awake tendon reconstruction surgery and to investigate the relationships between active contraction distance and the passive distraction distance and the time elapsed before reconstruction. METHODS: The passive distraction distance and active contraction distance of 36 tendons of 22 patients who underwent forearm tendon transfer or tendon graft during wide-awake surgery were measured. RESULTS: The passive distraction distance was significantly related to the active contraction distance of the ruptured musculotendinous unit (r = 0.60, P < 0.05). The passive distraction distance accounted for approximately half of the total excursion of the musculotendinous unit. There was no significant correlation between each distance and the time elapsed before reconstruction. CONCLUSIONS: The passive distraction distance was significantly related to the active contraction distance of the ruptured musculotendinous unit in vivo during wide-awake surgery. Active musculotendinous unit contraction distance may be a useful index to evaluate ruptured musculotendinous unit degeneration and donor muscle function in standard tendon reconstruction. This study suggested that the advantages of the wide-awake approach were not just as a clinical tool but also as an in vivo research tool.