Range of motion measurements do not correlate with patient reported outcome measures in the early post-operative period following ankle fracture

Abstract

Background: Early mobilization following ankle fracture open reduction and internal fixation (ORIF) improves long-term patient functionality. Because of this, numerous resources have been spent to increase patient adherence to post-operative mobilization, with range of motion (ROM) measurements generally considered an important outcome in patient recovery. In this study we investigated how ankle ROM correlates to patient function, self-sufficiency in performing activities of daily living (ADLs), and pain in the early post-operative period.

Methods: This was a prospective, observational study on patients undergoing ORIF of ankle fractures. We collected patient reported outcome measures (PROMs) and ROM measurements at the 2-week, 6-week, 12-week, and 6 month post-operative visit. We collected three PROMs: pain intensity (VAS), pain self-efficacy questionnaire (PSEQ-2), and foot and ankle ability measurement (FAAM). ROM of the ankle was measured by goniometer. ANOVA and post-hoc Tukey tests were used to examine statistical differences in PROMs over time. Pearson correlation tests were used to examine the association between ROM and PROMs.

Results: One-hundred and twenty-three participants enrolled in this study in the perioperative period. Pain intensity was higher at enrollment compared to week 6 (post-hoc p = 0.006), after which pain intensity did not differ significantly. FAAM scores for activities or daily living (ADL) were increased at all study visits compared to enrollment (post-hoc p < 0.001). FAAM-Sports scores were higher compared to enrollment at the week 12 and 6 month visits (post-hoc p < 0.001). No significant improvements in goniometer measurements were noted across any timepoints. There were no significant correlations between ROM and PROMs at any of the study visits.

Conclusion: In our cohort of patients, there was no correlation between ROM and patient pain, self-efficacy or functionality in the early post-operative period following ankle ORIF. The lack of correlation between PROMs and ROM indicates that ROM may be both a poor indicator of patient improvement for physicians to guide post-operative treatment as well as a poor motivator for patient adherence to post-operative exercises. In the future, it is important to study reliable outcome measures in early recovery that can be utilized to track patient recovery from ankle ORIF.

Keywords: Ankle fracture; Patient reported outcome measures; Range of motion.