title: Neurotization of free gracilis transfer with the brachialis branch of the musculocutaneous nerve to restore finger and thumb flexion in lower trunk brachial plexus injury: an anatomical study and case report.
abstract: OBJECTIVE
  To investigate the feasibility of using free gracilis muscle transfer along with the brachialis muscle branch of the musculocutaneous nerve to restore finger and thumb flexion in lower trunk brachial plexus injury according to an anatomical study and a case report.
  
  
  METHODS
  Thirty formalin-fixed upper extremities from 15 adult cadavers were used in this study. The distance from the point at which the brachialis muscle branch of the musculocutaneous nerve originates to the midpoint of the humeral condylar was measured, as well as the length, diameter, course and branch type of the brachialis muscle branch of the musculocutaneous nerve. An 18-year-old male who sustained an injury to the left brachial plexus underwent free gracilis transfer using the brachialis muscle branch of the musculocutaneous nerve as the donor nerve to restore finger and thumb flexion. Elbow flexion power and hand grip strength were recorded according to British Medical Research Council standards. Postoperative measures of the total active motion of the fingers were obtained monthly.
  
  
  RESULTS
  The mean length and diameter of the brachialis muscle branch of the musculocutaneous nerve were 52.66±6.45 and 1.39±0.09 mm, respectively, and three branching types were observed. For the patient, the first gracilis contraction occurred during the 4th month. A noticeable improvement was observed in digit flexion one year later; the muscle power was M4, and the total active motion of the fingers was 209°.
  
  
  CONCLUSIONS
  Repairing injury to the lower trunk of the brachial plexus by transferring the brachialis muscle branch of the musculocutaneous nerve to the anterior branch of the obturator nerve using a tension-free direct suture is technically feasible, and the clinical outcome was satisfactory in a single surgical patient.
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Orthopedic Trauma, Naval-Hospital, Guangzhou, China.
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Zou
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Fu
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Ben-Gang
authors.initials: BG
authors.lastname: Qin
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Jian-Tao
authors.initials: JT
authors.lastname: Yang
authors.affiliation: Department of Orthopedic Surgery, Henan University of Science and Technology, Luoyang, China.
authors.forename: Xiang-Ming
authors.initials: XM
authors.lastname: Li
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Hou
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Qi
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Liu
authors.affiliation: Department of Microsurgery and Orthopedic Trauma, Sun Yat-sen University, Guangzhou, China.
authors.forename: Li-Qiang
authors.initials: LQ
authors.lastname: Gu
mesh_terms: D000293:Adolescent; D001917:Brachial Plexus / Q000293:injuries*; D020516:Brachial Plexus Neuropathies / Q000503:physiopathology / Q000601:surgery*; D002102:Cadaver; D005240:Feasibility Studies; D005385:Fingers / Q000502:physiology*; D000071976:Gracilis Muscle / Q000294:innervation* / Q000601:surgery*; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D009138:Musculocutaneous Nerve / Q000637:transplantation*; D016067:Nerve Transfer / Q000379:methods; D016059:Range of Motion, Articular / Q000502:physiology; D013709:Tendon Transfer / Q000379:methods*; D013933:Thumb / Q000502:physiology