Neurologic complications after surgical management of complex elbow trauma requiring radial head replacement

Background: Radial head arthroplasty (RHA) has become a successful procedure for addressing acute unreconstructible radial head fractures that compromise elbow stability in complex elbow trauma. The purpose of this study was to investigate the incidence of and risk factors for the development of neurologic complications after surgical treatment of complex elbow fractures that require an RHA. Methods: Sixty-two patients with an unreconstructible radial head fracture and complex elbow instability treated with RHA were included. There were 33 men and 29 women, with a mean age of 54 years (range, 22-87 years). The average follow-up period was 5.2 years (range, 316 years). All patients were neurologically intact before surgery. The arthroplasty was implanted through a Kocher approach in 55 cases, whereas a Kaplan approach was used in 7. An uncemented smooth stem arthroplasty (Evolve) was used in 27 patients, and an anatomic ingrowth system (Anatomic Radial Head), in 35. At the time of surgery, 23 patients underwent fixation of a coronoid fracture and 15 underwent plating of the proximal ulna. All patients were clinically examined immediately after surgery and during follow-up to detect any degree of neurologic deficit. Radial and ulnar nerve injuries were classified according to the Hirachi and McGowan classifications, respectively. Functional outcomes were evaluated with the Mayo Elbow Performance Score. Results: A complete posterior interosseous nerve palsy occurred postoperatively in 2 patients. Hand function had completely recovered in both at 2 months after surgery without sequelae. Nine patients complained of ulnar nerve symptoms (immediately after surgery in 6 and as delayed ulnar neuropathy in 3). Most patients with ulnar nerve deficits had undergone additional surgical procedures to address ulnar fractures. Among patients with ulnar neuropathies, only 3 complained of mild sensory symptoms at the latest follow-up. No significant differences in range of motion and Mayo Elbow Performance Score were found between patients with and without neurologic complications. Associated olecranon or coronoid fixation and a prolonged tourniquet time were identified as risk factors for neurologic complications. Conclusion: This study shows that the incidence of neurologic complications associated with the surgical treatment of complex elbow fractures requiring implantation of a radial head prosthesis may be underestimated in the literature. Inappropriate retraction in the anterior aspect of the radial neck, a prolonged ischemia time, and concomitant coronoid or olecranon fracture fixation represent the main risk factors for the development of this complication. Although the great majority of patients have full recovery of their nerve function, they should be advised on the risk of this stressful complication. (C) 2020 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.