Yaiza Lópiz1,2, Pablo Checa3, Carlos García-Fernández1, Susana Martín Albarrán4, Rafael López de Ramón5, Fernando Marco1,2. 1. Shoulder and Elbow Unit, Department of Traumatology and Orthopaedic Surgery, Clínico San Carlos Hospital, 5º Planta, Ala Sur. Calle Profesor Martín Lagos S/N, 28004, Madrid, Spain. 2. Surgery Department, Complutense University, Madrid, Spain. 3. Shoulder and Elbow Unit, Department of Traumatology and Orthopaedic Surgery, Clínico San Carlos Hospital, 5º Planta, Ala Sur. Calle Profesor Martín Lagos S/N, 28004, Madrid, Spain. pachebet@gmail.com. 4. Department of Clinical Neurophysiology, Clínico San Carlos Hospital, Madrid, Spain. 5. Department of Traumatology and Orthopaedic Surgery, Ourense's Universitary Hospital Complex, Ourense, Spain.
Abstract
BACKGROUND: Alterations in the anatomical relationships of the musculocutaneous (MCN) and axillary nerves and the influence of arm positioning on these relationships after a Latarjet procedure have been demonstrated in the cadaver, but there are no studies in the literature that establish if there is any neurophysiological repercussion. METHODS: We retrospectively identified 24 patients with a primary or revision open Latarjet procedure. A prospective clinical (Constant-Murley, Rowe and Walch-Duplay and active range of motion), radiographic (with CT), and electrodiagnostic evaluation was made at the most recent follow-up. RESULTS: Nonunion occurred in four patients (22%); there were, as well, one case of partial coracoid reabsorption (5%) and two (11%) with mild glenohumeral osteoarthritis. In the anatomical position, we found no alterations in the musculocutaneous nerve and two cases (11%) in the axillary nerve slight motor unit loss. In the risk position, 11 cases (61%) had neurophysiological involvement (36% had neurophysiological changes in the musculocutaneous nerve and 64% in the axillary nerve). No differences between patients with or without neurophysiologic changes were found: Constant 87/83; Rowe 89/90; Walch-Duplay 84/78; Forward elevation 175º/170º, abduction 165°/175°; external rotation 48°/45°. CONCLUSION: The rate of clinical electromyographic changes in the axillary and MCN in the abducted and externally rotated arm position (risk dislocation position) is higher than in neutral position. Nonunion of the coracoid process must play a role in these neurophysiological changes. Although in the medium-term they don't have clinical impact, further randomized prospective studies with a larger sample size are necessary to determine their true repercussion. LEVEL OF EVIDENCE: Level IV.
BACKGROUND: Alterations in the anatomical relationships of the musculocutaneous (MCN) and axillary nerves and the influence of arm positioning on these relationships after a Latarjet procedure have been demonstrated in the cadaver, but there are no studies in the literature that establish if there is any neurophysiological repercussion. METHODS: We retrospectively identified 24 patients with a primary or revision open Latarjet procedure. A prospective clinical (Constant-Murley, Rowe and Walch-Duplay and active range of motion), radiographic (with CT), and electrodiagnostic evaluation was made at the most recent follow-up. RESULTS: Nonunion occurred in four patients (22%); there were, as well, one case of partial coracoid reabsorption (5%) and two (11%) with mild glenohumeral osteoarthritis. In the anatomical position, we found no alterations in the musculocutaneous nerve and two cases (11%) in the axillary nerve slight motor unit loss. In the risk position, 11 cases (61%) had neurophysiological involvement (36% had neurophysiological changes in the musculocutaneous nerve and 64% in the axillary nerve). No differences between patients with or without neurophysiologic changes were found: Constant 87/83; Rowe 89/90; Walch-Duplay 84/78; Forward elevation 175º/170º, abduction 165°/175°; external rotation 48°/45°. CONCLUSION: The rate of clinical electromyographic changes in the axillary and MCN in the abducted and externally rotated arm position (risk dislocation position) is higher than in neutral position. Nonunion of the coracoid process must play a role in these neurophysiological changes. Although in the medium-term they don't have clinical impact, further randomized prospective studies with a larger sample size are necessary to determine their true repercussion. LEVEL OF EVIDENCE: Level IV.
Authors: Christopher M LaPrade; Andrew S Bernhardson; Zachary S Aman; Gilbert Moatshe; Jorge Chahla; Grant J Dornan; Robert F LaPrade; Matthew T Provencher Journal: Am J Sports Med Date: 2018-05-24 Impact factor: 6.202
Authors: Michael T Freehill; Umasuthan Srikumaran; Kristin R Archer; Edward G McFarland; Steve A Petersen Journal: J Shoulder Elbow Surg Date: 2012-09-01 Impact factor: 3.019
Authors: Michael J Griesser; Joshua D Harris; Brett W McCoy; Waqas M Hussain; Morgan H Jones; Julie Y Bishop; Anthony Miniaci Journal: J Shoulder Elbow Surg Date: 2013-02 Impact factor: 3.019
Authors: Ruth A Delaney; Michael T Freehill; David R Janfaza; Kamen V Vlassakov; Laurence D Higgins; Jon J P Warner Journal: J Shoulder Elbow Surg Date: 2014-06-18 Impact factor: 3.019
Authors: Sanjeev Bhatia; Rachel M Frank; Neil S Ghodadra; Andrew R Hsu; Anthony A Romeo; Bernard R Bach; Pascal Boileau; Matthew T Provencher Journal: Arthroscopy Date: 2014-02 Impact factor: 4.772