Minimally invasive humeral shaft fractures osteosynthesis guided with intraoperative ultrassonography

• Grant number: 15/22912-7
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2016
• End date: June 30, 2018
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Bruno Livani
• Grantee: Bruno Livani
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated researchers: Mauricio Leal Dias Mongon ; William Dias Belangero

Abstract

Humeral shaft fractures (HSF) represent 1-3% of all human fractures, with an incidence of 14.5/100,000 adults up to fifty years to 60/100,000 adults aged from 90 to 100 years old. The radial nerve injuries related to HSF average incidence is 11% (range: 1.8% to 18%). Some authors recommend conservative treatment of those fractures with radial praxis claiming that over 80% of the nerve will recover spontaneously. However, other authors indicate immediate surgical exploration of the radial nerve and internal fixation of the fracture, based on the argument that spontaneous recovery of radial nerve is unlikely or at least unpredictable. Since the early 2000's the usage of minimally invasive plate osteosynthesis (MIPO) for HSF is universally accepted. Recently, surgical treatment with mechanical relative stability using MIPO technique was recognized for its safety, reproducibility and high fracture healing percentage with low complication rate. Several studies support MIPO technique safety and effectiveness for both, mid-diaphyseal and distal third humeral shaft fractures. However, recently a study using MIPO technique for the treatment of distal humeral fractures suggests that the radial nerve is visualized through a third window making this surgical procedure safer. Bodner et al reported the use of ultrasound (US) to visualize the radial nerve location. Based on these previous studies, Livani et al published a study using the US to measure the distance between the radial nerve and the implanted surgical hardware (MIPO) for the treatment of HSF.To date, no published studies have been conducted routinely using the US pre, intra and postoperative to identify and locate the radial nerve throughout the treatment of HSF with or without clinical radial nerve injury. The intraoperative use of the US can be an accurate and reliable method during surgical procedure to possibly avoid unnecessary exploration of the radial nerve or an iatrogenic injury of this nerve during the MIPO technique procedure. Patients and Methods.It will be a prospective study that will include all patients over 18 years of age, with HSF (with or without clinical radial nerve injury) and which is a surgical indication of the MIPO techniqueAfter the anesthetic induction, patients will undergo to preoperative US (before and after closed reduction maneuvers) with aseptic technique.Patients will be divided into two groups: Group I: patients that the US reveals that the radial nerve is not in the fracture site (either before or after closed reduction maneuvers). Group II: patients that the US reveals that the radial nerve is entrapped in the fracture site (either before or after the closed reduction maneuvers). In Group I the MIPO technique is conventionally performed (with a proximal and distal access, two-window bridge technique) avoiding the need for a third window to explore the radial nerve. In Group II, The third surgical window is performed and the nerve is identified and tagged with a Penrose drain in its emergence from the lateral intermuscular septum and released freely from distal to proximal to the fullest extent of this septum. All adhesion, nerve compression or entrapment between the bone fragments must be carefully dissected and released so that the radial nerve becomes loose and away from the bone fragments and the plate. For additional security, at the end of the surgical procedure is performed another US, to visualize the radial nerve and its anatomic relations between the fractured fragments and the implant. (AU)