Several factors associated with time to clinical union following ankle fracture

TORONTO — Tibiotalar dislocation, BMI, external fixation for initial stabilization and delay of definitive management significantly correlated with time to clinical union after ankle fracture, according to results presented at the American Orthopaedic Foot & Ankle Society Annual Meeting.

“We conclude that bony healing following surgical fixation of ankle fractures takes 16 weeks on average,” Andrew P. Matson, MD, said in his presentation here.

To determine factors linked with time to union, Matson and colleagues studied 112 patients treated for isolated, closed and malleolar ankle fractures. Patients had postoperative radiographs at 6 weeks, 12 weeks and 24 weeks after surgery and yearly thereafter. Cases of delayed union had additional radiographs at intervals of approximately 2 weeks.

“Our results demonstrated a mean time to union of almost 16 weeks,” Matson said. “Despite this high time to union, 90% of patients achieve union by 24 weeks.”

In their evaluation of gender, age, BMI, diabetes and tobacco use as factors for time to union, investigators found univariate analysis showed 86% of tobacco users had delayed union compared to 58% of non-tobacco users. This, researchers noted, was the only patient characteristic that appeared to have a statistically significant association with delayed union.

“When we looked at injury factors, including energy, presence of dislocation, injury pattern or delay of surgery, we found that energy of mechanism had a statistically significant association with time to union with an average of 18 weeks compared to low-energy mechanism of almost 15 weeks,” Matson said.

He added higher rates of delayed union were statistically significantly associated with definitive fixation involving both the medial malleolus and the fibula. Results showed statistically significant predictors of longer time to union also included BMI, presence of dislocation and delay of definitive management. – by Casey Tingle

Reference:

Matson AP, et al. Predictors of time to clinical union in ankle fractures. Presented at: American Orthopaedic Foot & Ankle Society Annual Meeting; July 21-23, 2016; Toronto.

Disclosure: Matson reports no relevant financial disclosures.