Six-year course and prognosis of nontraumatic knee symptoms in adults in general practice: A prospective cohort study

✍ Scribed by Marlous Kastelein; Pim A. J. Luijsterburg; Janneke N. Belo; Jan A. N. Verhaar; Bart W. Koes; Sita M. A. Bierma-Zeinstra

• Publisher: Wiley (John Wiley & Sons)
• Year: 2011
• Tongue: English
• Weight: 98 KB
• Volume: 63
• Category: Article
• ISSN: 2151-464X
• DOI: 10.1002/acr.20522

✦ Synopsis

Abstract

Objective

To examine the 6‐year course of nontraumatic knee symptoms in adults in general practice, to identify prognostic factors for unfavorable outcome, and to develop a clinical prediction rule.

Methods

Adults (ages >35 years) with incident nontraumatic knee symptoms (n = 549) were followed for 6 years. Multivariable logistic regression analysis was used to identify prognostic factors associated with an unfavorable outcome, the area under the receiver operating curve (AUC) was calculated to determine discriminative ability, and a clinical prediction rule was developed. Unfavorable outcome is defined as persistent knee symptoms at 6‐year followup or having undergone knee replacement surgery during followup.

Results

At 6‐year followup, 42.1% of patients had an unfavorable outcome. Having persistent knee symptoms (odds ratio [OR] 5.31, 95% confidence interval [95% CI] 3.27–8.61) and fulfilling the clinical American College of Rheumatology (ACR) criteria for osteoarthritis (OA; OR 2.65, 95% CI 1.48–4.73) at 1‐year followup were significantly associated with unfavorable outcome, while fulfilling the clinical ACR criteria for OA at baseline was not. Baseline factors independently associated with an unfavorable outcome were low/middle education level, comorbidity of the skeletal system, duration of knee symptoms of >3 months, bilateral knee symptoms, self‐reported warm knee, history of nontraumatic knee symptoms, valgus alignment, pain at passive knee flexion/extension, and bony enlargement of the knee joint (AUC 0.80).

Conclusion

Nontraumatic knee symptoms in adults in general practice appear to become a chronic disorder in nearly half of the patients. The developed clinical prediction rule with 10 baseline prognostic factors can be used to select high‐risk patients for an unfavorable outcome at long‐term followup.