Knee Osteoarthritis and Perceived Joint Instability

Knee Osteoarthritis and Perceived Joint Instability

by Maureen Ambrose PT, DPT, OCS

A common report among patients suffering from knee osteoarthritis is the feeling that the knee is buckling or “giving way” during weight bearing activities. This could occur while walking or going down stairs and contributes to avoidance of activities due to the fear of falling.

True knee instability would indicate that the knee ligaments are damaged or over-stretched (laxity) and have lost the ability to stabilize the femur and tibia bones of the knee joint. A recent study set out to determine if the sensation of knee instability that osteoarthritis patients report is actually due to ligament laxity.

35 patients (24 female, 11 male) from age 52-68 years old were examined 1 month before undergoing total knee arthroplasty (total knee replacement). They measured

  •  Knee extensor strength
  • Knee pain (self-reported)
  • Perception of knee instability
    o Slight to none (15 patients)
    o Moderate to severe (20 patients)
  • Knee Ligament laxity in the operating room just prior to total knee replacement

Results showed that poor knee extensor strength and high pain rating were the most associated with perceived moderate to severe knee instability.

Knee ligament laxity was actually not associated with perceived instability.

As a result of these findings we can suggest that increasing knee extensor (quadriceps) strength and reducing knee pain would result in the knee feeling more stable. If you are suffering from knee osteoarthritis that leaves your knee feeling like it is “giving way”, contact us at Physical Therapy First where we can design a program to help you feel more stable and confident during activities.

Perceived Instability Is Associated With Strength and Pain, Not Frontal Knee Laxity, in Patients With Advanced Knee Osteoarthritis .
Journal of Orthopaedic & Sports Physical Therapy, 2019,
Volume:49 Issue:7 Pages:513-517