A BIOMECHANICAL ANALYSIS OF INTRASCAPHOID COMPRESSION USING THE HERBERT SCAPHOID SCREW SYSTEM - AN IN-VITRO CADAVERIC STUDY

The purpose of this study was to evaluate the compressive capabilities of the Herbert scaphoid screw system. A transverse osteotomy was perf ormed at the waist of eight scaphoids removing a 3 mm wafer of bone. A custom-designed load washer was inserted within this defect to measur e intrascaphoid compression during Huene guide application, during scr ew insertion, after screw insertion and after guide release. The intra scaphoid compression was noted to peak during screw insertion; however it dramatically decreased without any clinical subjective evidence of decreased insertional torque by the surgeon. The average final compre ssion as a percentage of maximal compression was 38 (SD 26) %.