Fractures of the thigh bone (femur) just below the hip joint capsule (extracapsular hip fractures) may be surgically fixed using a variety of implants. One particular type of implant is the sliding hip screw, which consists of a screw that is inserted into the upper part of the (femur) to bridge (fix) the fracture. This screw can move within a metal barrel connected to a plate that is screwed to the outside of the femur. Implants of this sort of design are called 'extramedullary'. Intramedullary implants are nails inserted from the top of the femur into the inner cavity of the femur bone ('the medulla') and held in place with screws. This review compared these two types of implants in predominantly older populations.
The main results were for the comparisons of various types of intramedullary nails with the sliding hip screw. Twenty-two trials, involving 3749 participants, tested the Gamma nail. Five trials, involving 623 participants, tested the intramedullary hip screw (IMHS). Three trials, involving 394 participants, tested the proximal femoral nail. Other trials involved newer varieties of intramedullary nails. Most older trials showed a tendency for the nails to be associated with an increased risk of fracture of the thigh bone both during and after the operation. More recent trials testing newer varieties of nails seemed to avoid this specific problem to some extent. The review found that using intramedullary nails resulted in one extra reoperation in every 50 people. Mortality and, where data were available, other long-term outcomes were similar between the implants.
The review concluded that current evidence supports the continued use of the sliding hip screw for fixing the more common types of extracapsular hip fractures. This may not be the case for some of the more recently developed designs of intramedullary nails or for specific fracture types, but further research is required to confirm this.
With its lower complication rate in comparison with intramedullary nails, and absence of functional outcome data to the contrary, the SHS appears superior for trochanteric fractures. Further studies are required to confirm whether more recently developed designs of intramedullary nail avoid the complications of previous nails. Intramedullary nails may have advantages over fixed angle plates for subtrochanteric and some unstable trochanteric fractures, but further studies are required.
Two types of implants used for the surgical fixation of extracapsular hip fractures are cephalocondylic intramedullary nails, which are inserted into the femoral canal proximally to distally across the fracture, and extramedullary implants (e.g. the sliding hip screw).
To compare cephalocondylic intramedullary nails with extramedullary implants for extracapsular hip fractures in adults.
We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (April 2010), The Cochrane Central Register of Controlled Trials (The Cochrane Library 2010, Issue 1), MEDLINE (1950 to March 2010), EMBASE (1980 to 2010 Week 13), and other sources.
All randomised and quasi-randomised controlled trials comparing cephalocondylic nails with extramedullary implants for extracapsular hip fractures.
Both authors independently assessed trial quality and extracted data. Wherever appropriate, results were pooled.
We included 43 trials containing predominantly older people with mainly trochanteric fractures.
Twenty-two trials (3749 participants) compared the Gamma nail with the sliding hip screw (SHS). The Gamma nail was associated with increased risk of operative and later fracture of the femur and increased reoperation rate. There were no major differences between implants in wound infection, mortality or medical complications.
Five trials (623 participants) compared the intramedullary hip screw (IMHS) with the SHS. Fracture fixation complications were more common in the IMHS group. Results for post-operative complications, mortality and functional outcomes were similar in both groups.
Three trials (394 participants) showed no difference in fracture fixation complications, reoperation, wound infection and length of hospital stay for proximal femoral nail (PFN) versus the SHS.
None of the 10 trials (1491 participants) of other nail versus extramedullary implant comparisons for trochanteric fractures provided sufficient evidence to establish definite differences between the implants under test.
Two trials (65 participants) found intramedullary nails were associated with fewer fracture fixation complications than fixed nail plates for unstable fractures at the level of the lesser trochanter.
Two trials (124 participants) found a tendency to less fracture healing complications with the intramedullary nails compared with fixed nail plates for subtrochanteric fractures.