FDA Clears Implantable Shock Absorber to Treat Knee Osteoarthritis

woman receiving knee exam, osteoarthritis
Credit: Getty Images.
The device is implanted subcutaneously during an outpatient-compatible procedure.

The Food and Drug Administration (FDA) has cleared the MISHA Knee System for the treatment of medial knee osteoarthritis (OA) in patients who have failed to find relief from nonsurgical or surgical treatment, continue to experience pain that interferes with daily activities, and are ineligible for, or unwilling to undergo, joint replacement due to age or absence of advanced OA.

The MISHA Knee System is an implantable shock absorber that reduces a portion of the weight-bearing load on the knee joint, thereby easing pain and preserving function. The device is implanted subcutaneously during an outpatient-compatible procedure.

The approval was based on data from an open-label cohort study (ClinicalTrials.gov Identifier: NCT03671213) that compared the MISHA Knee System to high tibial osteotomy (HTO) in individuals 25 to 65 years of age with OA of the medial knee (N=81). Patients were eligible if their activity was limited by knee pain, they failed conservative treatments (eg, injections, braces) and had radiographic evidence of OA.

Findings showed that the MISHA Knee System was superior to HTO, demonstrating improvements in pain relief (based on Western Ontario and McMasters University Osteoarthritis Index [WOMAC] pain score), function (based on WOMAC function score), and safety. Recovery time following the procedure (defined as full weight-bearing without assist devices) was reported to be 4 times shorter with the MISHA Knee System vs HTO.

Commenting on the approval, Anil Ranawat, MD, Chief, Hip and Knee Division of Sports Medicine Institute, Hospital for Special Surgery in New York, and study investigator said: “With the FDA’s clearance of the MISHA Knee System, millions of people with symptomatic knee OA will now have an opportunity to achieve high levels of pain relief, enjoy the lifestyle and activities that are important to them, and preserve the option for a primary knee arthroplasty in the future. This system fills that void for both surgeons and patients.”


  1. FDA authorizes marketing of MISHA Knee System for people suffering from knee osteoarthritis. News release. Moximed. April 10, 2023. https://www.businesswire.com/news/home/20230410005434/en/FDA-Authorizes-Marketing-of-MISHA%E2%84%A2-Knee-System-for-People-Suffering-from-Knee-Osteoarthritis.
  2. Diduch DR, Crawford DC, Flanigan DC, et al. Implantable shock absorber provides superior pain relief and functional improvement compared with high tibial osteotomy in patients with mild-to-moderate medial knee osteoarthritis: A 2-year report. Cartilage. Published online February 23, 2023. doi:10.1177/19476035231157335