Morphometry of radial head: A guide for radial head prosthesis

Abstract

Introduction: Radial head fractures constitute one-third of all elbow fractures and 20% of all trauma cases. The head, being the key element is very important for maintaining stability and biomechanics of the humeroradial joint. Treatment of radial head fractures involves fixation or replacement with radial head prosthesis. However, the designing of prosthesis requires accurate knowledge of morphometry of proximal radius for a specific population to restore normal joint mechanics and joint morphometry. Henceforth, this study was carried out to determine dimensions of radial head in the North Indian subjects. Materials and methods: The present observational study was conducted on one hundred dry adult human radii with an intact upper end. The parameters included Anteroposterior diameter of radial head (APD), Transverse diameter of radial head (TD), Medial height of radial head (MH], Lateral height of radial head (LH), Anterior height of radial head (AH), Posterior height of radial head (PH), Depth of superior articular facet (D), Surface area of head of radius (SA), Volume of head of radius (VOL), Ventral curve (VC), Dorsal curve (DC), Lateral curve (LC) and Circumference of the head (C). The side dimorphism was noted for any statistically significant side dimorphism. Results: The morphometry of radial head revealed that the APD, TD were lesser by 2mm to 3mm as compared with western studies. The VC and the PC in the western studies were lesser by 0.4mm and 0.6mm respectively as compared to the current study. Conclusions: These parameters are of importance for orthopaedic surgeons in the treatment of fractures of the upper radius, where a radial head implant or prosthesis is required. Accurately matched prosthesis in accordance with the size of head will reduce postoperative complications and result in better operative outcome. Keywords: Radial head, Radial head prosthesis, Morphometry, Humororadial joint