title: Force recovery assessment of functioning free muscle transfers using ultrasonography.
abstract: OBJECTIVE
  To evaluate the usefulness of ultrasonography for measurement of functioning free muscle transfer strength and estimate the capacity and potential of ultrasonography measurement.
  
  
  METHODS
  Twenty-five patients underwent functioning free muscle transfer for brachial plexus injury. The cross-sectional areas (CSAs) of the transferred muscle and the contralateral gracilis (control) were measured using ultrasonography. First, the reliability and reproducibility of the ultrasonography measurements of the muscle CSA was investigated. Next, force recovery was evaluated by calculating the contraction ratio (CR), which was defined as the value equal to the CSA of the transferred muscle under maximum isometric contraction divided by the CSA value in a complete rest position. The CR of the contralateral gracilis was calculated in the same manner. The CR of the transferred muscle and the control were compared statistically. We also analyzed the correlation between the CR of the transferred muscle and other measurements of muscle strength. The follow-up duration was 24 to 87 months after surgery.
  
  
  RESULTS
  The reliability and reproducibility of the ultrasonography measurements was determined statistically. The CR of the transferred muscle (1.30 ± 0.12) was significantly greater than that of the contralateral gracilis (1.22 ± 0.13). Furthermore, the CR of the transferred muscle showed significant correlations with both manual muscle testing and elbow arc of motion.
  
  
  CONCLUSIONS
  Ultrasonography measurement of transferred muscle can easily indicate the recovery process of rehabilitation in a quantitative and dynamic manner. This study demonstrated that ultrasonography has the capacity to evaluate force recovery objectively.
  
  
  METHODS
  Therapeutic IV.
authors.affiliation: Department of Orthopaedic Surgery, Ogori Daiichi General Hospital, Yamaguchi, Japan. Electronic address: koda62@belle.shiga-med.ac.jp.
authors.forename: Narihito
authors.initials: N
authors.lastname: Kodama
authors.affiliation: Department of Orthopaedic Surgery, Ogori Daiichi General Hospital, Yamaguchi, Japan.
authors.forename: Kazuteru
authors.initials: K
authors.lastname: Doi
authors.affiliation: Department of Orthopaedic Surgery, Ogori Daiichi General Hospital, Yamaguchi, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Hattori
mesh_terms: D000293:Adolescent; D000328:Adult; D001917:Brachial Plexus / Q000293:injuries*; D020516:Brachial Plexus Neuropathies / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D058752:Free Tissue Flaps / Q000098:blood supply / Q000294:innervation / Q000502:physiology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000637:transplantation*; D020127:Recovery of Function / Q000502:physiology; D015203:Reproducibility of Results; D016896:Treatment Outcome; D014463:Ultrasonography; D055815:Young Adult
keywords: Functioning free muscle transfer; cross-sectional area; ultrasonography