"How You can Prevent Knee Pain from Arthritis" 

September 4, 2009 — Quadriceps strength does not predict the occurrence of radiographic knee osteoarthritis (OA) in either sex but predicts lower incidence of painful or stiff knee OA in women, according to the results of a longitudinal cohort study reported in the September 15 issue of Arthritis Care & Research.

Arthritis in the Knee usually occurs on the medial (inside part) of the knee

"Knee...OA is a major public health concern worldwide and one of the foremost causes of chronic disability in older adults," write Neil Segal, MD, MS, from the University of Iowa Hospitals and Clinics in Iowa City, and colleagues. "There is evidence that muscle dysfunction is involved in the pathogenesis of knee OA."

In the Multicenter Osteoarthritis Study (MOST), 3026 men and women aged 50 to 79 years were observed for a 30-month period to determine whether knee extensor strength would predict incident radiographic or symptomatic knee OA characterized by pain, aching, or stiffness on most days of the preceding month. For the study of radiographic knee OA, 2519 knees were evaluated in 1617 participants who did not have radiographic tibiofemoral OA at baseline, and 3392 knees were assessed for combined radiographic OA and symptomatic OA in 2078 participants without this combination of findings at baseline.

Using an isokinetic dynamometer, the investigators determined quadriceps muscle strength for knee extension and the balance of muscle strength between the hamstrings and quadriceps (H:Q ratio) as a measure of lower extremity musculature. Knee radiographs to determine the presence of OA were performed at baseline and at study end, and a telephone screen at both time points identified the presence of frequent knee pain, aching, or stiffness. Other measurements included height, weight body mass index (BMI), femoral neck bone mineral density (BMD), and physical activity status.

Knee Exercises to Help Strengthen Knee:

1.  Lower Extremity Matrix:  peform 2 sets of 10 to each side.  This is a great beginner exercise before progressing to lunges.

2.  Lunges:  Work up to performing 2 sets of 10.  If you have really bad knees and poor strength, perform the lunge shallow or just do the lower extremity matrix.

3.  Single Leg Balancing:  This is a great starter for anyone with knee pain.  Work your way up to 1 minute without touching the foot to the ground.  If you have poor balance keep you hand up close to the wall as demonstrated.

Generalized estimating equations accounted for 2 knees per participants. Multivariable models allowed adjustment for age, BMI, hip BMD, knee surgery or pain, and physical activity score.

Radiographic evidence of knee OA was present at study end in 48 of 680 men and 93 of 937 women, and symptomatic whole-knee OA was present at 30 months in 10.1% of women and 7.8% of men.

Women in the top tertile of peak knee extensor strength had a significantly lower incidence of symptomatic knee OA vs those in the lowest tertile. Compared with men with weaker knee extensor strength, however, those with strong quadriceps muscles had only slightly lower risk of not developing OA symptoms.

"Our results showed thigh muscle strength was not a significant predictor of radiographic knee OA," the study authors wrote. "The H:Q ratios were not predictive of symptomatic knee OA in either men or women."

Limitations of this study include lack of measurement of hip abductor strength and failure to identify individuals who had frequent knee symptoms outside of the 30-day window asked about on the questionnaire.

"Study of hip abductor strength, which is important for control of the knee joint, may be useful in a more comprehensive study of risk for OA of the knee," Dr. Segal said in a news release. "These findings suggest that targeted interventions to reduce risk for symptomatic knee OA could be directed toward increasing knee extensor strength."

The National Institute on Aging funded this study. Some of the authors have disclosed various financial relationships with the Association of American Physiatrists and the National Institutes of Health.

Arthritis Care Res. 2009;61:1210-1217. Abstract

 Dr. Bryan Dingsor is the owner of Watertown Chiropractic P.C. in Watertown, SD. He specializes in the treatment of many musculoskeletal conditions and weight loss. For an appointment, please call 605-882-2304 Today.