abstract
- INTRODUCTION: This article describes a technique in which measurements are obtained from radiographs of the contralateral, normal elbow to predict the magnitude of overlengthening resulting from use of a metallic radial head prosthesis. STEP 1 OBTAIN BILATERAL ELBOW RADIOGRAPHS: Obtain bilateral digital anteroposterior radiographs of the elbows that are orthogonal to the forearm in 45° of flexion and neutral forearm rotation. STEP 2 PERFORM RADIOGRAPHIC MEASUREMENTS OF THE CONTRALATERAL NORMAL ELBOW: Draw the angle on the radiograph of the normal elbow. STEP 3 PERFORM RADIOGRAPHIC MEASUREMENTS OF THE RADIAL HEAD IMPLANT: Draw the same lines and angle and perform the same measurements on the implant radiograph. STEP 4 CALCULATE RADIAL HEAD IMPLANT LENGTH: The virtual length of the native radial head implant (L-NRH) is subtracted from the virtual length of the radial head implant (L-RHI), which results in the magnitude of the radial head implant overlengthening in millimeters: (L-RHI) - (L-NRH) = overlengthening. RESULTS: The radiographic measurement technique was validated in a cadaveric study. WHAT TO WATCH FOR: IndicationsContraindicationsPitfalls & Challenges.