Pattern of Recovery and Outcomes of Patient Reported Physical Function and Pain Interference After Ankle Fusion: A Retrospective Cohort Study

SLR - January 2021 - Donald D. Cohen

Reference: Kohring JM, Houck JR, Oh I, Flemister AS, Ketz JP, Baumhauer JF. Pattern of Recovery and Outcomes of Patient Reported Physical Function and Pain Interference After Ankle Fusion: A Retrospective Cohort Study. J Patient Rep Outcomes. 2020;4(1):40. Published 2020 May 27. doi:10.1186/s41687-020-00203-y

Level of Evidence: Level II, Prospective single cohort study.

Scientific Literature Review

Reviewed By: Donald D. Cohen, DPM 
Residency Program: Saint Vincent Hospital – Worcester, MA

Podiatric Relevance: The majority of research regarding outcomes following ankle fusion focuses on outcomes based on basic activities of daily living, fusion rate and gait parameters. Although this offers good insight into surgical outcomes following an ankle arthrodesis, the patient satisfaction and perspective is often missed. This allows us, as clinicians, to provide a better and more effective treatment to our patients following surgery. The patient perspective, so long as the provider listens, acts as a guideline as to how we can build patient expectation, increase provider communication and provide an overall better surgical experience all together.

Methods: This study is a  retrospective review of  prospectively collected patient outcomes. The authors utilized a patient reported outcome measurement information system (PROMIS) to evaluate 88 ankle arthrodesis procedures performed over three years. During routine care and visits, physical function (PF) and pain interference (PI) measures were collected. These values were collected prior to their appointments via computer survey. Analysis of post-operative outcomes for these two measures were then followed for a year. T-scores which showed greater than 4 points improvement, PROMIS-Preference scores for PF and PI were then analyzed and reported. Results were placed through a linear mixed model analysis in different day ranges.

Results: The day ranges for PI following 90-119 days, and a PF after 120-149 days revealed a patient reported plateau at 57-59 days and 39-40 days for PI and PF, respectively. The change in pain interference revealed a -5.4 T-score improvement, suggesting a statistically significant improvement. This was analyzed at a 95 percent confidence interval. 66.2 percent of patients reported a T-score improvement of greater than four for either PI, PF, or both PI and PF. The pain interference score was the only reported value of significance. 

Conclusions: Resolution of pain happens more frequently following ankle arthrodesis, rather than physical function or both physical function and pain together. This study suggests that, although patients show interval improvement for up to a year post-operatively, the most significant finding was how the patient felt at four months. The average patient recovery showed progressive improvement in pain and function until the four month postoperative time point. This means that an increase in pain or a reduction in function after month four post-op could suggest further complications, such as nonunion, and warrant further investigation. This study can help the podiatric surgeon in preoperative counseling and postoperative expectation management for patients with end stage ankle arthritis.