Abstract
Background
Controversy persists regarding preference between Herbert and Acutrak screw for internal fixation of scaphoid non-union. Acutrak screw has been shown to have better biomechanical compression properties than Herbert screw in the laboratory setting. The aim of this study was to assess the clinical, radiological and functional outcome of patients treated with the two different screw systems.
Methods
A retrospective review of the results of patients with scaphoid non-union treated by a single surgeon. Group 1 comprised of 61 patients treated with Herbert screw between July1996 and June2000 and Group 2 comprised of 71 patients treated with Acutrak screw between July 2000 and December 2005. Union rates were assessed radiologically and clinically. Functional outcome was measured by using modified Mayo wrist score.
Results
Both groups of patients were comparable in terms of age (25.3:27.3yrs, Herbert: Acutrak) and their occupations in relation to wrist loading. The mean time interval between injury and surgery was 12.2months for Herbert group (range: 3–144months) and 17months (range: 4–180months) in Acutrak group. Time to union was similar for both groups. Union rate was 93% (66) in Acutrak compared to 77% (47) in Herbert screw. Union rate was related to fracture site (Herbert p=0.01; Acutrak p=0.0001) and higher when the screw had been placed axially (Herbert; p=0.006, Acutrak; p=0.004) in the scaphoid. Ninety seven percent of screws had been placed axially in Acutrak compared to 84% in the Herbert. Functional outcome was satisfactory in 85% of Acutrak group compared to 67% in Herbert. Wrist fusion was performed in 4 patients in Herbert group due to progressive wrist pain and in 1 patient in Acutrak group due to similar reason.
Conclusion
Acutrak screw provides more accurate method of screw placement and a higher union rate when compared to Herbert screw.
