Opening Wedge High Tibial Osteotomy

High Tibial Opening Wedge Osteotomy and Conservative Treatment in Medial Knee Osteoarthritis - A Randomised Controlled Trial

A prospective, randomised controlled trial where clinical and radiological outcome of high tibial opening wedge osteotomy with physiotherapy is compared to physiotherapy alone while treating symptomatic medial knee osteoarthrosis.

90 Symptomatic patients with mild to moderate medial knee osteoarthrosis are randomized to two groups:

Group 1 (HTO-group) receive an diagnostic arthroscopy with high tibial opening wedge osteotomy (Tomofix-plate). Postoperatively a supervised physiotherapeutic rehabilitation program is started.

Group 2 (FT-group) receive the same supervised physiotherapeutic rehabilitation program without the HTO or arthroscopy.

Primary outcome measure is composite score of Knee injury and Osteoarthritis Outcome Score (KOOS5).

Secondary outcome measures are pain (VAS), KOOS subscales, objective physical performance measurements, progression of osteoarthrosis (X-ray, MRI), change of mechanical axis, complications, treatment costs, rate of reoperation, revision to total knee arthroplasty (TKA), biological markers of arthrosis progression, 15D (quality of life assessment), QALY (Quality-Adjusted Life-Year), Work Productivity and Activity Impairment Questionnaire, Work Productivity and Activity Impairment Questionnaire, sum of governmental benefits received.

Outcomes will be measured at 24, 60 and 120 months after the intervention.

Inclusion Criteria:

• Pain: Subjective pain in the knee most of the month for at least one month during past 12 months.
• Knee range of motion (ROM) at least 5-120 degrees
• X-ray: medial joint space Altman > 1. Lateral joint space Altman < 2.
• Mechanical axis > 3 degrees varus alignment.
• Medial proximal tibial angle (MPTA) < 90 degrees
• age 25-55.
• Written consent, accepts both treatment arms.

Exclusion Criteria:

• Pain is caused by something else than medial knee osteoarthrosis
• deficient ROM (flexion contracture > 10 degrees, flexion < 110 degrees)
• significant ligament instability
• post traumatic OA
• clinically relevant neurological disease (e.g. Alzheimer´s disease)
• clinically relevant metabolical disease (e.g. Diabetes)
• alcohol/drug abuse
• infectious/inflammatory joint disease
• previous knee area osteotomy or lower limb arthroplasty
• smoking (> 0 cigarette per day)
• obesity (BMI > 33)
• pregnancy or hope of pregnancy in the following two years