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Updated: Aug 25, 2026

Collection of Skeletal Muscle Biopsies from the Superior Compartment of Human Musculus Tibialis Anterior for Mechanical Evaluation
Published on: September 27, 2020
Intramuscular innervation of upper-limb skeletal muscles
Aymeric Y T Lim1, Barry P Pereira, V Prem Kumar
1Department of Hand and Reconstructive Microsurgery, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074. dosbarry@nus.edu.sg
Abstract:
We studied 150 skeletal muscles from 8 upper limbs using the modified Sihler's staining technique. Based on the pattern of the intramuscular innervation and shape, the muscles were grouped into trapezoidal-shaped (Class I), spindle-shaped (Class II), and muscles that were combinations of these two classes (Class III). Such distinctions are clinically important for limb reconstruction procedures. Bipennate, spindle-shaped muscles with the aponeurosis of the tendons of insertion extending proximally into the muscle belly and Class III muscles with multiple tendons of origin may be split for separate independent functional transfers.
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