Rotational Alignment in Tibia Diaphyseal Fractures With the Suprapatellar Semiextended versus Standard Upper Entry Tibial Intramedullary Nailing: A Randomized Controlled Trial (RASPUTIN).

Abstract

To determine whether suprapatellar or infrapatellar approach makes a difference in the rate of rotational malalignment in tibial diaphyseal fractures treated with intramedullary nailing. Noninferiority, randomized controlled trial, with two arms (suprapatellar and infrapatellar approaches). Single-center trial at a Level I trauma center in South India. Adults presenting with tibial diaphyseal fractures (OTA/AO 42A, B and C, 43A) planned for intramedullary nailing between September 2021 and July 2022. The primary outcome compared was the degree of rotational malalignment in patients undergoing tibia nailing with suprapatellar and infrapatellar approaches. This was performed using CT scan in the immediate postoperative period. Secondary outcomes assessed across the 2 groups were postoperative entry site pain, anterior knee pain (Kujala score), functional scores, and union rates. Fifty patients, 25 in each arm, were included and followed up to a period of 1 year. The mean age was 34 (16-67) years (68% male) in the suprapatellar group and 45 (16-72) years (72% male) in the infrapatellar group. The rate of rotational malalignment was 34% with 8 (32%) in the suprapatellar group and 9 (36%) in the infrapatellar group and was independent of the approach used ( P = 0.76). The rotational malalignment had no association with knee functional scores ( P = 0.24). Factors such as location of fracture ( P = 0.81), mechanism of injury ( P = 0.76), type of injury ( P = 0.24), and surgeon seniority ( P = 0.2) had no association with malrotation. Suprapatellar and infrapatellar groups were similar in knee function ( P = 0.52), knee ( P = 0.31) and ankle ( P = 0.23) range of movement, and union rates ( P = 0.84). Entry site pain was found to be significantly less ( P = 0.021) in the suprapatellar group (6/25) as compared with the infrapatellar group (14/25). This difference persisted at 1 year. Rotational malalignment in tibial diaphyseal fractures treated by intramedullary nailing was independent of the approach used. Entry site pain was less common with the suprapatellar approach. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.