Minimally invasive internal fixation for extra-articular distal radius fracture: Comparison between volar plate and intramedullary nail.

INTRODUCTION:There are numerous internal fixation techniques for distal radius fracture, using pins, plates or nails. Some authors have developed minimally invasive procedures. The aim of the present study was to compare two minimally invasive internal fixation techniques for unstable extra-articular distal radius fracture in women over 50 years of age: volar plate (minimally invasive plate osteosynthesis: MIPO), and intramedullary nail. HYPOTHESES:The main study hypothesis was that the incision scar left by minimally invasive internal fixation is smaller using MIPO than an intramedullary nail. The secondary hypotheses were that the two techniques do not differ in terms of pain, functional score, strength, range of motion and radiologic indices. MATERIAL AND METHOD:The series comprised nineteen A2.2 and one A2.1 fractures in 20 female patients with a mean age of 72 years. The first 10 (group 1) received minimally invasive internal fixation of the distal radius by MIPO, and the other 10 (group 2) by intramedullary nail locked onto the distal radius epiphysis and diaphysis. RESULTS:The main study hypothesis was confirmed: the incision scar left by minimally invasive internal fixation was smaller using MIPO than an intramedullary nail (mean, 14.3mm vs. 32.8mm). Some of the secondary hypotheses were also confirmed: there were no differences between the two techniques in terms of pain at 6 months, QuickDASH, PRWE (Patient-Reported Wrist Evaluation), range of motion or ulnar variance; two were not confirmed: pain at 6 weeks was less with intramedullary nails, and palmar slope was better with MIPO. DISCUSSION AND CONCLUSION:The main study hypothesis was confirmed: the incision scar left by minimally invasive internal fixation was smaller using MIPO than an intramedullary nail. In conclusion, the present findings showed that internal fixation of unstable extra-articular fracture in over 50-year-olds gave better clinical results at 6 weeks using an intramedullary nail, while MIPO required smaller incision. LEVEL OF EVIDENCE:III, retrospective study.