americanscience.org jof http://www. ) 11 2013;9( Journal of American Science 220 Lateral Closing Wedge Osteotomy of the Radial Styloid in Treatment of Scaphoid Proximal Pole Nonunion with AVN Ezzat H Fouly 1 and Ahmed F Sadek 2 1 Consultant Orthopedic Surgeon, 2 Lecturer of Orthopedic Surgery and Traumatology, Minia, University Hospital, Egypt ezatfoli2004@yahoo.com Abstract: Nonunion is the most common complication after scaphoid fracture treatment especially proximal pole fracture. Because the vascular supply of the proximal pole primarily relies on vessels entering the scaphoid more distal, thereby making the proximal pole particularly susceptible to ischemic changes placing it at risk for avascular necrosis (AVN). Furthermore the radial styloid essentially functions as a fulcrum against the center of the scaphoid, resulting in the predominance of fracture. Over long time, patients may then experience pain, instability, and eventual collapse of the proximal pole that leads to intercarpal or radiocarpal arthritis. Eight patients with symptomatic nonunion of the proximal pole fracture of the scaphoid with AVN had been treated by excision of the proximal pole and lateral closing wedge osteotomy of the radial styloid. The average age was 37 years. The average time of delay before the operation was 27 months. The average duration of follow up period was 10 months. The radial deviation, grip strength and the resting pain improved and the changes were statistically significant. This technique is a simple procedure and effective technique for management of scaphoid proximal pole nonunion with AVN. [Ezzat H. Fouly, and Ahmed F. Sadek. Control of the Activity of Pseudomonas Aeruginosa by Positive Electric Impulses at Resonance Frequency Am Sci 2013;9(11):220-224]. (ISSN: 1545-1003). http://www.jofamericanscience.org . 30 Key Words: styloid osteotomy, scaphoid nonunion, AVN, proximal pole 1. Introduction The unique anatomy of the scaphoid predisposes its fractures to delayed union or nonunion and to disability of the wrist. The proximal pole is vascularized nearly exclusively from intraosseous vessels. Fractures through the proximal third of the scaphoid have a high rate of devascularizing the proximal fragment 1 . Non-union of the scaphoid ranges from 5% to 50% and it usually causes pain and weakness, also it would result in carpal osteoarthritis 2 . Treatment of scaphoid nonunion remains a challenging problem, especially in the setting of proximal pole avascular necrosis. The options for treatment of nonunion of proximal pole fractures depend on the blood supply to the proximal pole and the size of the fragments 3 . Despite the best efforts in diagnosis and treatment, failure of the persistent scaphoid nonunion to heal may occur. Theoretically, the use of pedicled vascularized bone grafts (VBG), which help revascularize ischemic bone, should improve the union rate and time to union 4 , but, unfortunately, not all reports on the use of VBG have been favorable 5 . A metaanalysis of treatment of scaphoid nonunion with osteonecrosis of the proximal pole indicated an 88% union rate with a VBG 6 . Pedicled dorsal distal radius VBG has been reported to have nearly a 50% failure rate when used in scaphoid nonunion with proximal pole AVN 7 . Straw etal at 2002 reported on Zaidemberg's technique, only 2 of 16 nonunions with avascular proximal poles (12.5%) united 8 . They concluded that pedicled vascularized bone grafting may not improve the union rate for scaphoid fracture nonunion with avascular proximal pole fragments 6 . To avoid collapse of the carpus and painful arthritis, a salvage procedure is likely to be necessary 9 . Many salvage procedures can be done one of them is radial styloidectomy with partial scaphoid excision 10 . Partial scaphoid excision can be performed without disrupting wrist biomechanics if the proximal pole fracture fragment is small 11, 12 . The main risk following a radial styloidectomy is ulnar translocation of the carpus 13 . Nakamura et al observed significantly increased radial translation with ulnar and palmar carpal displacement after radial styloidectomy. Excessive styloid resection may result in scaphoid instability by transection the origin of the radioscaphocapitate ligament and loss of the radial buttress of the articular surface toward the carpus 14 .