Restoration of Winged Scapula in Upper Arm Type Brachial Plexus Injury: Anatomic Feasibility
Rattavuth Raksakulkiat MD*, Somsak Leechavengvongs MD**, Kanchai Malungpaishrope MD**, Chairoj Uerpairojkit MD**, Kiat Witoonchart MD**, Sukumal Chongthammakun PhD***
Affiliation : * Department of Orthopaedics, Vajira Hospital, Bangkok, Thailand ** Upper Extremity & Reconstructive Microsurgery Unit, Institute of Orthopaedics, Lerdsin General Hospital, Bangkok, Thailand *** Department of Anatomy, Mahidol University, Bangkok, Thailand
Background : The patients who have C5-C6 root avulsion in brachial plexus injury, suffered from loss of elbow
flexion, shoulder abduction and winged scapula. The purpose of study is to provide anatomic feasibility of
thoracodorsal nerve (medial and lateral branches) and long thoracic nerve for restoration of the shoulder
function caused by winged scapula.
Material and Method: To study the length of thoracodorsal nerve and long thoracic nerve from the apex of
the posterior axillary line to the insertion of the latissimus dorsi muscle and the serratus anterior muscle
respectively, 10 fresh cadavers were dissected. The distance between the thoracodorsal nerve and long
thoracic nerve, and the numbers of fascicles and axon were measured by histomorphometry. We transferred the
lateral branch of the thoracodorsal nerve to the long thoracic nerve in order to restore the serratus anterior
muscle function.
Results : The mean length of the thoracodorsal nerve from apex of posterior axillary line to bifurcation before
separation to medial and lateral branches was 31.5 mm. The average length of the thoracodorsal nerve and
long thoracic nerve from bifurcation to the insertion of the latissimus dorsi muscle and the serratus anterior
muscle were 10.3, 82.2, and 99.5 mm, respectively. The distance between the lateral branch of the thoracodorsal
nerve and long thoracic nerve was 33.4 mm. The mean number of myelinated nerve fiber of the thoracodorsal
nerve medial and lateral branches and long thoracic nerve were 973.8, 1843.3 and 1135.3 axons, respectively.
Conclusion : The anatomic study of the thoracodorsal nerve and long thoracic nerve showed that the lateral
branch of the thoracodorsal nerve is proper in the length and numbers of axon to transfer to the long thoracic
nerve for restoration of shoulder function caused by the winged scapula.
Keywords : Brachial plexus injury, nerve transfer, Long thoracic nerve, Thoracodorsal nerve, winged scapula
