A preliminary study on B -mode ultrasonic evaluation of muscle recovery after functional gracilis muscle transplantation

Abstract

Objective To investigate the value of the B-mode ultrasound method for muscle recovery after transplantation. Methods From January, 2009 to January, 2014, 35 patients of functioning free gracilis muscle transplantation for brachial plexus injury were involved. Using B-mode ultrasound to determine the cross-sectional area (CSA) of transplanted gracilismuscle at rest and contraction state. The contraction ratio (CR) and the muscle bulk ratio (MBR) was calculated based on the CSA. Then the CR and MBR were analysised statistically with manual muscle strength and joint range of motion (ROM) to investigate the correlation. Results The followed-up time was 8-24 months, averaged of 22.4 months. The CR of the transplated muscle was (1.23±0.15), which was significantly correlated with muscle strength and joint ROM (P 0.05). There was no statistically significant difference in muscle strength and ROM between patients with MBR greater than 1 and those with MBR less than 1 (P= 0.054, P=0.284, respectively). Conclusion The transplanted muscle recovery can be quantitatively reflected by the CR. CR enlargement of the transplanted gracilis muscle indicated a better recovery of muscle contraction function. MBR is not suitable for evaluating function recovery of transplanted muscles. Key words: Gracilis; Functional muscle transplantation; B-mode ultrasound; Muscle contraction; Muscle strength