Effect of Early Weight Bearing on Outcomes After Open Reduction and Internal Fixation of Trimalleolar Ankle Fractures

SLR - September 2021 - Conor Ross Keeley

Reference: Myers DM, Pulido SH, Forsting S, Umbel B, Taylor BC. Effect of Early Weight Bearing on Outcomes After Open Reduction and Internal Fixation of Trimalleolar Ankle Fractures. Orthopedics. 2021 May-Jun;44(3)-160-165

Level of Evidence: Level III

Scientific Literature Review

Reviewed By: Conor Ross Keeley, DPM
Residency Program: University of Florida Health – Jacksonville, FL

Podiatric Relevance: Trimalleolar ankle fractures are high energy injuries with lengthy recovery periods. The potential for early weight bearing post-operatively can have many advantages for patients.

Methods: This was a retrospective comparative review of 185 patients with operative trimalleolar ankle fractures treated from 2010-2019 at an urban level 1 trauma center by one of the five fellowship-trained orthopedic traumatologists. Exclusion criteria were patients under 18 years old, follow up time of less than six months, primary arthrodesis, use of external fixation, or prior ankle surgeries. Patients were sorted into two groups, early weight bearing (EWB) or late weight bearing (LWB) based on whether they initiated weight bearing before or after three weeks post-operatively. Forty-seven patients were in the EWB group (25.4 percent) and 138 patients were in the LWB group (74.6 percent). Patients were evaluated for union, hardware failure, infection, ambulatory status and return to surgery.

Results: The only demographic difference between the two groups was the rate of illicit drug use with 21.2 percent in EWB and 7.9 percent in LWB. There was no significant difference in sex, weight, age, BMI, diabetes, A1C, neuropathy, tobacco use, employment or open fracture.

The EWB and LWB showed a significant difference in only the following measurements:
-    Posterior malleolus fixation 51.1 percentin EWB and 34.8 percent in LWB
-    Syndesmotic fixation 21.3 percent in EWB and 46.3 percent in LWB
-    Estimated blood loss 99.2 ± 109.9 mL in EWB and 65.9 ± 69.9 mL in LWB
-    Time to weight bearing 2.9 ± 0.2 weeks in EWB and 9.6 ± 4.2 weeks in LWB

There was no statistically significant difference between the two groups for operative time, superficial infection, deep infection, return to OR, implant failure, decreased ambulatory status or non-union.

A binary logistic regression analysis was then performed with all the cases to identify predictors of union and nonunion. Syndesmotic fixation increased the union rate by 2.5 times. Open fracture increased the nonunion rate by 3.8 times. Deep infection increased the nonunion rate by three times.
                
Conclusions: This study showed that early weightbearing following trimalleolar fractures does not have an increased risk of complications. Early weight bearing has been shown in many other studies to have benefits for patients compared to prolonged non weight bearing periods. This study is most significantly limited by its retrospective nature and not having functional outcome scores.