INTERMEDIATE TERM FUNCTIONAL OUTCOMES AFTER ARTHROSCOPIC KNEE SURGERY

Eric C. McCarty, MD, Kurt P. Spindler, MD, Michelle Secic, MS,
W. Grear Hurt, MD, and Elizabeth Turnipseed, BS

Objective:
Traditionally, assessment of patient function has been based on symptoms, clinical exam findings and radiographs. The use of patient-oriented questionnaires validated for outcome measures has only recently been employed. This study investigated demographic, intraarticular pathology and treatment as positive outcome predictors in 4 to 7 years after knee arthroscopy.

Methods:
The analysis consisted of 218 patients with minimum 4-year follow-up with single unilateral knee arthroscopy (single surgeon) in a ligamentously stable knee without other major lower extremity problems. Intraarticular knee pathology and treatment were recorded on diagrams and forms and function follow-up was by self-administered questionnaire which included SF-36, WOMAC, KOOS, Lysholm, and IKDC. Both univariate and multivariate statistical analyses were performed to determine statistically significant intraarticular and demographic variables at intermediate follow-up with the outcomes questionnaires, global scores, subscale scores, and functional status.

Results:
Multivariable modeling revealed gender (male) and patellar/trochlear degenerative pathology as the only consistent statistically significant (p<0.05) independent predictors of poor outcome with the KOOS, the IKDC, and the WOMAC scores. Other factors found to be significant were: age (p=0.037) in the KOOS symptoms/stiffness model, complete meniscus tear in the WOMAC stiffness (p=0.006, medial) and SF-36 Mental Health (p=0.046, lateral) models. Articular cartilage degeneration was significant only in the MFC with advanced models. Articular cartilage degeneration was significant only in the MFC with advanced (Grade IV) arthritis vs early (Grade I-III) changes in the KOOS model, and for the LFC was significant in both early and advanced in the KOOS model and in sports/recreation function, quality of life and overall scores.

Conclusions:
The overall functional outcome after operative knee arthroscopy as assessed by validated questionnaires is most highly correlated by articular cartilage status, especially patellofemoral arthritis, as well as gender with males having statistically significant worse outcomes scores than females. Meniscal treatment did not significantly affect scores at follow-up. The results of this study may assist the counseling of patients regarding expectations of functional outcomes following knee arthroscopy.