Abstract
Fixation with a dynamic hip screw (DHS) is one of the most common methods for stabilizing intertrochanteric fractures, except for unstable and reverse oblique fracture types. However, failure is often observed in osteoporotic patients whereby the lag screw effectively ‘cuts out’ through the weak bone. Novel anti-migration blades have been developed to be used in combination with a lag screw (‘Blade Screw’) to improve the fixation strength in osteoporotic intertrochanteric fractures. An in-vitro biomechanical study and a retrospective clinical study were performed to evaluate lag screw migration when using the novel Blade Screw and a traditional threaded DHS. The biomechanical study showed both the Blade Screw and DHS displayed excessive migration (≥10 mm) before reaching 20,000 loading cycles in mild osteoporotic bone, but overall migration of the Blade Screw was significantly less (p ≤ 0.03). Among the patients implanted with a Blade Screw in the clinical study, there was no significant variation in screw migration at 3-months follow-up (P = 0.12). However, the patient’s implanted with a DHS did display significantly greater migration (P<0.001) than those implanted with the Blade Screw. In conclusion, the Blade Screw stabilizes the bone fragments during dynamic loading so as to provide significantly greater resistance to screw migration in patients with mild osteoporosis.
Highlights
Intertrochanteric fractures are common injuries in the elderly and are often a consequence of sudden impact to an osteoporotic hip, such as that experienced during a fall [1]
The mean number of cycles achieved by the Blade Screw and traditional dynamic hip screw (DHS) were 11,000±409 and 6,200±250 cycles respectively
The displacement of the femoral head (DFH), displacement of the distal lag screw tip (DDLS), varus collapse (VC), and RN of the Blade Screw group were all significantly smaller than those recorded from the traditional DHS group at the point of excessive migration (p 0.03; Table 1)
Summary
Intertrochanteric fractures are common injuries in the elderly and are often a consequence of sudden impact to an osteoporotic hip, such as that experienced during a fall [1]. Anti-Migration Blade Screw Design for Sliding Hip Fixations of Intertrochanteric Fractures. Postoperative fracture instability with secondary complications is frequently reported in severely osteoporotic patients [1,2,3,4,5]. In a sample of 178 intertrochanteric fractures treated with a DHS with a minimum of one year follow-up, Kim et al [5] reported a complication rate in osteoporotic bone of greater than 50%. Poor bone quality is a major risk factor for intertrochanteric fractures, which could lead to an increased failure rate for implants or collapse and lag screw cut-out from the superior aspect in older patients [3,4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
