Dataset for: Musculotendon adaptations but preservation of spinal reflex pathways following agonist-to-antagonist tendon transfer

Tendon transfer surgeries are performed to restore lost motor function, but outcomes are variable, particularly those involving agonist-to-antagonist muscles. Here, we evaluated the possibility that lack of proprioceptive feedback reorganization and musculotendon adaptations could influence outcomes. Plantaris to tibialis anterior tendon transfer along with resection of the distal third of the tibialis anterior muscle belly was performed in 8 cats. Four cats had concurrent transection of the deep peroneal nerve. After 15-20 weeks, intermuscular length and force dependent sensory feedback were examined between hindlimb muscles, and the integrity of the tendon-to-tendon connection and musculotendon adaptations were evaluated. Three of the transferred tendons tore. A common finding was the formation of new tendinous connections, which often inserted near the original location of insertion on the skeleton (e.g. connections from plantaris toward calcaneus and from tibialis anterior toward first metatarsal). The newly formed tissue connections are expected to compromise the mechanical action of the transferred muscle. We found no evidence of changes in intermuscular reflexes between transferred plantaris muscle and synergists/antagonists whether the tendon-to-tendon connection remained intact or tore, indicating no spinal reflex reorganization. We propose the lack of spinal reflex reorganization could contribute to altered task dependent temporal activation of the transferred muscle. Taken together, these findings suggest musculotendon plasticity and lack of spinal reflex circuitry reorganization could limit functional outcomes after tendon transfer surgery. Surgical planning and outcomes assessments after tendon transfer surgery should consider potential consequences of the transferred muscle’s intermuscular spinal circuit actions.

肌腱转移术（tendon transfer surgery）用于恢复丧失的运动功能，但术后预后存在差异，尤其是涉及主动肌-拮抗肌（agonist-to-antagonist muscles）的转移手术。本研究旨在探讨本体感觉反馈（proprioceptive feedback）重塑缺失以及肌腱（musculotendon）适应性改变是否会影响手术预后。我们对8只家猫实施了跖肌（plantaris）-胫骨前肌（tibialis anterior）肌腱转移术，同时切除胫骨前肌肌腹的远端三分之一；其中4只家猫同时接受了腓深神经（deep peroneal nerve）切断术。术后15至20周，检测后肢肌肉间的肌间长度与肌力依赖性感觉反馈，并评估肌腱-肌腱连接的完整性及肌腱适应性改变。转移的肌腱中有3根发生撕裂。常见的研究发现为新腱性连接的形成，这类连接通常附着于骨骼的原附着点附近（例如：跖肌向跟骨（calcaneus）的连接、胫骨前肌向第一跖骨（first metatarsal）的连接）。这类新形成的组织连接预计会损害转移肌肉的力学功能。我们未发现转移跖肌与其协同肌/拮抗肌之间的肌间反射发生改变，无论肌腱-肌腱连接是否保持完整或发生撕裂，这表明未出现脊髓反射（spinal reflex）重塑。我们推测，脊髓反射重塑的缺失可能会导致转移肌肉的任务依赖性时序激活模式发生改变。综合来看，本研究结果表明，肌腱可塑性以及脊髓反射环路重塑的缺失，可能会限制肌腱转移术后的功能预后。肌腱转移术的手术规划及术后预后评估，应考虑转移肌肉的肌间脊髓环路活动所带来的潜在影响。