Does the Use of Locking Screws Decrease the Rate of Hardware Removal in Ankle Fractures?

SLR - May 2019 - Eric M. Swenson

Reference:  Walley, K. C., Gonzalez, T. A., Nandyala, S. V., Macauley, A., Elnabawi, Y., Rodriguez, E. K., & Appleton, P. T. (2019). Does the Use of Locking Screws Decrease the Rate of Hardware Removal in Ankle Fractures? Foot & Ankle Specialist.

Scientific Literature Review

Reviewed By: Eric M. Swenson, DPM
Residency Program: Mount Auburn Hospital, Cambridge, MA

Podiatric Relevance: Depending on where you practice, ankle fractures are commonly encountered and treated by foot and ankle surgeons. When utilizing any type of surgical hardware to reduce and correct traumatic ankle fractures, hardware removal must always be considered. There are many factors that help formulate the proper decision regarding type of hardware to be utilized, ranging from surgical training, surgeon comfort level/preference, fracture pattern and overall patient factors. Locking plates were originally developed as fixed-angle devices for the fixation of long-bone fractures, however, they have also been found to be useful in Charcot midfoot disease. Some clinically advantageous properties of locking plates include the preservation of periosteal blood supply, usefulness with osteoporotic bone, bridging properties in incidents of bone loss as well as minimal invasiveness. To add to this list, locking plates provide a biomechanically stable fixed-angle construct without the requirement of particular anatomical contouring. This study retrospectively reviewed the efficacy and complication rates of locking screws versus traditional nonlocking screws in 135 patients with complex ankle fractures utilizing distal fibula internal fixation with 1/3 semitubular small fragment plates.

Methods: A level III retrospective review from January 2010 to June 2013 was performed for all patients who underwent internal fixation of the fibula in an ankle fracture via only 1/3 semitubular small fragment fibular plates. A total of 135 patients with open (22 patients) or closed (113 patients) ankle fractures, including syndesmotic injury and polytrauma, were identified. Screws placed in the distal two fibular plate holes were characterized as either locking (98 patients) or nonlocking (37 patients) and recorded. Infection and the need and purpose for hardware removal was identified and recorded.

Results: Patients with nonlocking screws required fewer hardware removals, however, this was not statistically significant. There were no statistically significant differences appreciated regarding age, smoking status, BMI, diabetes or use of syndesmotic screw fixation. No significant differences were seen in loss of fixation, infection and other surgical complications. Hardware failure and infection rate was higher in the locking screw group. Painful hardware was higher with the nonlocking group.
    
Conclusions: There were no statistically significant differences found with the use of locking vs. nonlocking screws regarding the rate of hardware removal in the setting of distal fibular fractures fixated with 1/3 semitubular plates. Due to the retrospective design of this study, there were a number of limitations, including concern for selection bias, surgery performed by a few isolated surgeons, small sample size and short-term follow-up period of only six months. The additional expense of utilizing distal locking screws when fixating distal fibular fractures should not be implemented routinely but rather when indicated by fracture patterns and bone quality. Moreover, further studies are warranted to support these findings with larger sample sizes and longer follow-up duration.