Correlation of the AOFAS Scores with a Generic Health Qualy Score in Foot and Ankle Surgery

Abstract

Background: The American Orthopaedic Foot and Ankle Score (AOFAS) is one scoring system used to assess and monitor the progress of patients after foot and ankle surgery. The aim of this study was to evaluate the trend of the AOFAS score over a period of time and correlate it with the QUALY score, which is a valid and reliable scoring system. Methods: All patients undergoing surgery by one foot and ankle surgeon between January, 2001, and July, 2003, were reviewed. The preoperative AOFAS and QUALY and postoperative scores at 3, 6 and 12 months, and yearly were collected prospectively. Results: This study includes 204 operative procedures in 159 patients. The mean age of the patients was 51.9 (range 12 to 89) years. The AOFAS scores increased from a mean of 45.5 preoperatively to 76.5 at 3 months and reached a peak of 81.5 at 6 months and then started to decrease to 79.2 at 12 months. This fall, though seemingly marginal, was significant (p < 0. 01). This trend seems to be consistent for all the procedures. The 6-month AOFAS score was found to have a higher correlation with the final QUALY score (r ² = 0.423) than the 12-month AOFAS score (r ² = 0.326). Conclusions: The AOFAS score has low levels of correlation with the validated generic health QUALY score. Our study suggests that scores collected preoperatively, at 6 and 12 months after surgery, and annually there after may be best. The 3-month score may not be necessary. We recommend that a generic health score such as the QUALY score be used in conjunction with the AOFAS score to reflect outcome.

Keywords

AOFAS and QUALY Scores Foot and Ankle Scores

Get full access to this article

View all access options for this article.

References

1. Budiman-Mak

Conrad

Roack

: The Foot Function Index: a measure of foot pain and disability. J. Clin. Epidemiol. 44:561–570, 1991.

2. Button

Pinney

: A meta-analysis of outcome rating scales in foot and ankle surgeries: is there a valid, reliable and responsive system?. Foot Ankle Int. 25:521–525; 2004.

3. Guyton

: Theoretical limitations of the AOFAS scoring systems: an analysis using Monte Carlo modeling. Foot Ankle Int. 22:779–787, 2001.

4. Kitaoka

Alexander

Adelaar

Nunley

Myerson

: Clinical rating systems for the ankle-hindfoot, midfoot, hallux and lesser toes. Foot Ankle Int. 15:349–353, 1994.

5. Nyska

: Principles of first metatarsal osteotomies. Foot Ankle Clin. 6: 399–408, 2001.

6. Pynsent

Fairbank

Carr

: Outcome measures in orthopaedics, In O'Doherty

(ed.) The Foot and Ankle, Butterworth-Heinmann, London, pp. 246–268, 1993.

7. Parker

Nester

Long

Barrie

: The problem with measuring patient perceptions of outcome with existing outcome measures in foot and ankle surgery. Foot Ankle Int. 24:56–60, 2003.

8. Radford

: General outcomes measures, In Pynsent

Fairbank

Carr

(eds). Outcome Measures in Orthopaedics, Butterworth-Heinmann, London, pp. 59–80, 1993.

9. Rosser

Kind

: A scale for valuation of state of illness: Is there a social consensus? Int. J. Epidemiol. 7:347–358, 1978.

10.

10. Schneider

Knahr

: Scoring in forefoot surgery: a statistical evaluation of single variables and rating systems. Acta Orthop. Scand. 69:498–504, 1998.

11.

11. SooHoo

Shuler

Fleming

: Evaluation of the validity of the AOFAS clinical rating systems by correlation to the SF-36. Foot Ankle Int. 24:50–55, 2003.

12.

12. Toolan

Wright, Quinones

Cunningham

Brage

: An evaluation of the use of retrospectively acquired preoperative AOFAS clinical rating scores to assess surgical outcome after elective foot and ankle surgery. Foot Ankle Int. 22:775–778, 2001.