استفاده از ميدان مغناطيسي براي قراردادن پيچ هاي قفل كننده در ميله هاي داخل كانال استخواني (يك روش ابداعي )

Efficacy of Distal Screw Placement by Magnetic Field without X-rays ( An Innovative Method )

Insertion of distal interlocking screws in interlocking intramedullary I.M. Rods is a demanding procedure. Although closed IM nailing, as an ideal internal fixation method, needs X-Ray to send the guide wire past the fracture site, some surgeons prefer making a small incision at fracture site and pass it manually. To find the. distal holes of the rod, however, X-Ray has been considered unavoidable up to now. By this innovative method of applying a magnetic field, the hole sites can be precisely marked on the outer bone cortex. 63 distal holes were locked in 35 intramedullary nailings of femur and tibia by four orthopaedic surgeons. Distal screw fixation took only 5.2 ± 2 minutes in each case. During the total procedures there were 5 "error holes" ( three of them from the use of template for the second hole instead of repeat use of magnet ), 3 misplaced screws ( 4.8%) and 8 single X-Rays Exposures used for placing 6 screws while 57 distal bolts were correctly placed without any X-Ray. Omitting the X-Rays, the easy and cheap magnetic method can replace expensive, hazardous and time - consuming free - hand procedure in placing distal screws. A true expriemental study is recommended.