Trial Outcomes & Findings for Comparing Ankle Fusion to Ankle Replacement (NCT NCT01620541)

NCT ID: NCT01620541

Last Updated: 2026-08-21

Results Overview

Ankle specific function was assessed using the Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) subscale, a validated, self-reported questionnaire which measures functional ability during activities of daily living. \[CH1.1\]The FAAM ADL subscale sums and coverts responses to a standardized score ranging from 0 to 100%. A score of 0% represents complete disability, and a score of 100% represents no functional limitations. Higher scores indicate better ankle function.

Recruitment status

COMPLETED

Target enrollment

517 participants

Primary outcome timeframe

Before surgery, 1 year post-op, 2 years post-op, 4 years post-op, and 8 years post-op

Results posted on

2026-08-21

Participant Flow

Protocol Enrollment should be 517

Participant milestones

Participant milestones
Measure
Preference, Ankle Arthrodesis
Participants received ankle arthrodesis to treat ESAA
Preference, Ankle Arthroplasty
Participants received ankle arthroplasty to treat ESAA
Overall Study
STARTED
103
414
Overall Study
COMPLETED
17
93
Overall Study
NOT COMPLETED
86
321

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Comparing Ankle Fusion to Ankle Replacement

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Total
n=517 Participants
Total of all reporting groups
Age, Customized
Age +/- (yr)
54.2 years
STANDARD_DEVIATION 12.7 • n=5 Participants
63.2 years
STANDARD_DEVIATION 9.7 • n=109 Participants
61.4 years
STANDARD_DEVIATION 10.9 • n=133 Participants
Sex/Gender, Customized
Male
61 Participants
n=5 Participants
237 Participants
n=109 Participants
298 Participants
n=133 Participants
Sex/Gender, Customized
Female
42 Participants
n=5 Participants
177 Participants
n=109 Participants
219 Participants
n=133 Participants
Race (NIH/OMB)
American Indian or Alaska Native
1 Participants
n=5 Participants
3 Participants
n=109 Participants
4 Participants
n=133 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
2 Participants
n=109 Participants
2 Participants
n=133 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
0 Participants
n=109 Participants
0 Participants
n=133 Participants
Race (NIH/OMB)
Black or African American
1 Participants
n=5 Participants
5 Participants
n=109 Participants
6 Participants
n=133 Participants
Race (NIH/OMB)
White
100 Participants
n=5 Participants
403 Participants
n=109 Participants
503 Participants
n=133 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=5 Participants
0 Participants
n=109 Participants
0 Participants
n=133 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants
n=5 Participants
1 Participants
n=109 Participants
2 Participants
n=133 Participants

PRIMARY outcome

Timeframe: Before surgery, 1 year post-op, 2 years post-op, 4 years post-op, and 8 years post-op

Ankle specific function was assessed using the Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) subscale, a validated, self-reported questionnaire which measures functional ability during activities of daily living. \[CH1.1\]The FAAM ADL subscale sums and coverts responses to a standardized score ranging from 0 to 100%. A score of 0% represents complete disability, and a score of 100% represents no functional limitations. Higher scores indicate better ankle function.

Outcome measures

Outcome measures
Measure
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Change in Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
Pre-op
46.6 Scores on a scale
Standard Error 1.3
48.3 Scores on a scale
Standard Error 2
Change in Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
1 year
81.3 Scores on a scale
Standard Error 1.3
71.6 Scores on a scale
Standard Error 2
Change in Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
2 years
81.8 Scores on a scale
Standard Error 1.3
73.7 Scores on a scale
Standard Error 2
Change in Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
4 years
79.9 Scores on a scale
Standard Error 1.2
71.8 Scores on a scale
Standard Error 2
Change in Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
8 years
75.9 Scores on a scale
Standard Error 1.5
67.1 Scores on a scale
Standard Error 2.6

PRIMARY outcome

Timeframe: Before surgery, 1 year post-op, 2 years post-op, 4 years post-op, and 8 years post-op

Ankle specific function during sports activities was measured using the Foot and Ankle Ability Measure (FAAM) Sports subscale, a validated, self-reported questionnaire which measures functional ability during sport-related activities. The FAAM Sports subscale sums and converts responses to a standardized score ranging from 0 to 100%. A score of 0% represents complete disability, and a score of 100% represents no functional limitations. Higher scores indicate better ankle function during sports activities.

Outcome measures

Outcome measures
Measure
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Change in Foot and Ankle Ability Measure (FAAM) Sports Subscale Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
Pre-op
19.6 Scores on a scale
Standard Error 1.9
21.8 Scores on a scale
Standard Error 2.9
Change in Foot and Ankle Ability Measure (FAAM) Sports Subscale Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
1 year
59.1 Scores on a scale
Standard Error 1.9
45.5 Scores on a scale
Standard Error 3
Change in Foot and Ankle Ability Measure (FAAM) Sports Subscale Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
2 years
59.7 Scores on a scale
Standard Error 1.9
52.3 Scores on a scale
Standard Error 2.9
Change in Foot and Ankle Ability Measure (FAAM) Sports Subscale Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
4 years
56.6 Scores on a scale
Standard Error 1.9
50.1 Scores on a scale
Standard Error 2.8
Change in Foot and Ankle Ability Measure (FAAM) Sports Subscale Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
8 years
49.3 Scores on a scale
Standard Error 2.2
46.1 Scores on a scale
Standard Error 3.9

PRIMARY outcome

Timeframe: Before surgery, 1 year post-op, 2 years post-op, 4 years post-op, and 8 years post-op

Ankle specific function was assessed using the Short Form-36 (SF-36) Physical Component Summary (PCS) score, a validated, generic measure of health-related quality of life that evaluates physical health status. The PCS score is derived from responses to the SF-36 questionnaire and is norm-based, with scores ranging from 0-100, where higher scores indicate better physical health and lower scores indicate poorer physical health.

Outcome measures

Outcome measures
Measure
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Change in Short Form-36 (SF-36) Physical Component Summary (PCS) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
8 years
43.2 Scores on a Scale
Standard Error 0.6
42.6 Scores on a Scale
Standard Error 1.2
Change in Short Form-36 (SF-36) Physical Component Summary (PCS) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
Pre-op
34.2 Scores on a Scale
Standard Error 0.5
35.9 Scores on a Scale
Standard Error 0.9
Change in Short Form-36 (SF-36) Physical Component Summary (PCS) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
1 year
46.9 Scores on a Scale
Standard Error 0.5
44.3 Scores on a Scale
Standard Error 1.0
Change in Short Form-36 (SF-36) Physical Component Summary (PCS) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
2 years
46.6 Scores on a Scale
Standard Error 0.5
44.1 Scores on a Scale
Standard Error 0.9
Change in Short Form-36 (SF-36) Physical Component Summary (PCS) Score Between Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty
4 years
45.3 Scores on a Scale
Standard Error 0.4
43.7 Scores on a Scale
Standard Error 0.9

PRIMARY outcome

Timeframe: Before surgery, 1 year post-op, 2 years post-op, 4 years post-op, and 8 years post-op

Pain was assessed using two questions from the Chronic Pain Grade (CPG), including intensity of worst pain in past 6 months. This was scored on a 0-10 point scale where higher scores represented greater pain (e.g., 0 = "no pain" and 10 = "pain as bad as it could be")

Outcome measures

Outcome measures
Measure
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Worst Pain)
Pre-op
8.5 Scores on a scale
Standard Error 0.2
8.3 Scores on a scale
Standard Error 0.3
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Worst Pain)
1 year
3.6 Scores on a scale
Standard Error 0.2
4.2 Scores on a scale
Standard Error 0.3
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Worst Pain)
2 years
3.1 Scores on a scale
Standard Error 0.2
4.0 Scores on a scale
Standard Error 0.3
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Worst Pain)
4 years
3.2 Scores on a scale
Standard Error 0.2
3.8 Scores on a scale
Standard Error 0.3
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Worst Pain)
8 years
3.1 Scores on a scale
Standard Error 0.2
3.4 Scores on a scale
Standard Error 0.4

PRIMARY outcome

Timeframe: Before surgery, 1 year post-op, 2 years post-op, 4 years post-op, and 8 years post-op

Pain was assessed using two questions from the Chronic Pain Grade (CPG), including intensity of average ankle pain in past 6 months. This was scored on a 0-10 point scale where higher scores represented greater pain (e.g., 0 = "no pain" and 10 = "pain as bad as it could be")

Outcome measures

Outcome measures
Measure
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Average Pain)
Pre-op
6.3 Scores on a scale
Standard Error 0.1
6 Scores on a scale
Standard Error 0.2
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Average Pain)
1 year
2.1 Scores on a scale
Standard Error 0.1
2.7 Scores on a scale
Standard Error 0.2
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Average Pain)
2 years
1.9 Scores on a scale
Standard Error 0.1
2.5 Scores on a scale
Standard Error 0.2
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Average Pain)
4 years
2.0 Scores on a scale
Standard Error 0.1
2.5 Scores on a scale
Standard Error 0.2
Change in Overall Pain Intensity and Ankle Specific Pain Intensity; Interference With Activities in Subjects Undergoing Ankle Arthrodesis and Total Ankle Arthroplasty (Average Pain)
8 years
2.1 Scores on a scale
Standard Error 0.1
2.4 Scores on a scale
Standard Error 0.3

SECONDARY outcome

Timeframe: Assessed monthly until 12 months after surgery

Population: Sites attempted to record complications after 12 months but the tracking and reporting proved too difficult across sites to capture and summarize. Please see adverse events for details of the complications comparing arthroplasty to arthrodesis over the first 12 months after surgery.

Ankle-specific complications in the 12-month period post surgery

Outcome measures

Outcome measures
Measure
Preference, Ankle Arthroplasty
n=414 Participants
Participants received ankle arthroplasty to treat ESAA
Preference, Ankle Arthrodesis
n=103 Participants
Participants received ankle arthrodesis to treat ESAA
Post-surgical Complication Rates
33 Participants
17 Participants

SECONDARY outcome

Timeframe: Before surgery and at 6, 12, and 24 months after surgery

Population: While change in step counts were an intended secondary outcome, unfortunately step counts were not collected as sites were unable to obtain step counters for patients.

Step counts using a StepWatch Activity Monitor, worn for a 7-14 day time period.

Outcome measures

Outcome data not reported

Adverse Events

Preference, Ankle Arthrodesis

Serious events: 4 serious events
Other events: 13 other events
Deaths: 0 deaths

Preference, Ankle Arthroplasty

Serious events: 7 serious events
Other events: 26 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Preference, Ankle Arthrodesis
n=103 participants at risk
Participants received ankle arthrodesis to treat ESAA
Preference, Ankle Arthroplasty
n=414 participants at risk
Participants received ankle arthroplasty to treat ESAA
Musculoskeletal and connective tissue disorders
Major Surgical Revisions
3.9%
4/103 • from enrollment up to 12 months post-surgery
1.7%
7/414 • from enrollment up to 12 months post-surgery

Other adverse events

Other adverse events
Measure
Preference, Ankle Arthrodesis
n=103 participants at risk
Participants received ankle arthrodesis to treat ESAA
Preference, Ankle Arthroplasty
n=414 participants at risk
Participants received ankle arthroplasty to treat ESAA
Musculoskeletal and connective tissue disorders
Minor Surgical Revisions
8.7%
9/103 • from enrollment up to 12 months post-surgery
2.2%
9/414 • from enrollment up to 12 months post-surgery
Musculoskeletal and connective tissue disorders
Minor Adverse Event
3.9%
4/103 • from enrollment up to 12 months post-surgery
4.1%
17/414 • from enrollment up to 12 months post-surgery

Additional Information

Dan Norvell

Veterans Affairs

Phone: 253-906-5308

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place