title: Transfer of the pronator quadratus motor branch for wrist extension reconstruction in brachial plexus palsy.
abstract: BACKGROUND
  In extended upper-type lesions of the brachial plexus, nerve transfers and root grafting have improved the results of shoulder and elbow reconstruction. However, wrist extension reconstruction has received little attention.
  
  
  METHODS
  In 20 cadaveric upper limbs, we dissected the anterior interosseous nerve and extensor carpi radialis brevis motor branch. Four patients with upper-type lesions of the brachial plexus with paralysis of wrist and finger extension were operated on within 10 months of trauma and followed up for 12 months after surgery. The terminal division of the anterior interosseous nerve, which innervates the pronator quadratus muscle, was transferred to the extensor carpi radialis brevis, and the distal stump was connected to a motor fascicle of the median nerve (n = 2) or to the distal branch of the flexor superficialis of the index finger (n = 2).
  
  
  RESULTS
  The anterior interosseous nerve and extensor carpi radialis brevis had similar diameters (roughly 1 mm). The number of myelinated fibers in the nerve averaged 670, whereas the number in the extensor carpi radialis brevis averaged 183. The length of the nerve was approximately 80 mm, allowing for direct transfer to the extensor carpi radialis brevis with redundant length. At last evaluation, pronation scored M4 according to the Medical Research Council grading system. All patients recovered active wrist extension, scoring M4 with full, independent motor control.
  
  
  CONCLUSIONS
  In C5 to C8 root injuries of the brachial plexus, transfer of the motor branch of the pronator quadratus to the extensor carpi radialis brevis can restore active wrist extension, and pronation is preserved.
  
  
  METHODS
  : Therapeutic, IV.
authors.affiliation: Florianópolis and Tubarão, Santa Catarina, Brazil From the Department of Orthopedic Surgery, Governador Celso Ramos Hospital; the Center of Biological and Health Sciences, University of the South of Santa Catarina (Unisul); and the Department of Anatomy, Federal University of Santa Catarina.
authors.forename: Jayme A
authors.initials: JA
authors.lastname: Bertelli
authors.forename: Cristiano P
authors.initials: CP
authors.lastname: Tacca
authors.forename: Elisa C
authors.initials: EC
authors.lastname: Winkelmann Duarte
authors.forename: Marcos F
authors.initials: MF
authors.lastname: Ghizoni
authors.forename: Hamilton
authors.initials: H
authors.lastname: Duarte
mesh_terms: D000328:Adult; D001917:Brachial Plexus / Q000293:injuries* / Q000601:surgery; D005500:Follow-Up Studies; D005542:Forearm / Q000294:innervation* / Q000601:surgery; D006801:Humans; D008297:Male; D016067:Nerve Transfer / Q000379:methods*; D010243:Paralysis / Q000209:etiology / Q000601:surgery*; D059348:Peripheral Nerve Injuries / Q000150:complications / Q000601:surgery*; D016896:Treatment Outcome; D014953:Wrist / Q000294:innervation / Q000503:physiopathology*