A Randomized Trial Comparing High Tibial Osteotomy Plus Non-Surgical Treatment and Non-Surgical Treatment Alone

This two groups, parallel design randomized controlled trial will compare patients with medial compartment knee OA and varus alignment receiving optimized non-surgical treatment plus High Tibial Osteotomy (HTO) to similar patients receiving optimized non-surgical treatment only. All participants will receive non-surgical treatment that will be individualized to the patient and include medications, physiotherapy and nutritional seminars. The non-surgical treatment will include supervised physiotherapy and nutritional seminars once per week for 12 weeks, will be accompanied and followed by a home program, and follow-up appointments for potential modification every three months for the duration of the study. Participants randomized to surgery will also undergo medial opening wedge HTO after 12 weeks of optimized non-surgical treatment. Both groups will follow the same schedule of clinic visits throughout the 24 month follow-up period. MRI-derived measures of articular cartilage morphology, biological markers of articular cartilage degradation and synthesis, gait biomechanics and patient-reported outcomes will be assessed at baseline, 12 and 24 months follow-up.

Inclusion criteria

• Is the subject either:

• 25-55 years old?
• Older than 55 but still active (ex. physical labour, regular recreational activities)?
• Does this subject present with varus alignment? (Based on hip to ankle x-rays).
• Does this subject have clinical Knee OA? (MAA <-2° on full limb standing AP) according to the Altman classification primarily involving the medial compartment of the knee?
• Patient is a good candidate for high tibial osteotomy and will be receiving a PEEK plate, or if receiving an alternate plate, agrees to have the plate removed prior to 1 year postoperative.

Exclusion criteria

• Has this subject had a previous HTO or joint replacement in either limb?
• Is this subject likely to undergo bilateral HTO within the 2 year follow up period?
• Does this subject have an unstable knee or ligament?
• Does this subject have inflammatory or infectious arthritis of the knee?
• Radiographic disease too advanced for HTO (ie. diffuse lateral compartment, patellofemoral joint OA and/or severe enough disease to suggest that joint replacement is the better surgical option) and/or Kellgren and Lawrence grade 4.
• The subject's disease is not advanced enough (symptomatically or radiographically) to warrant HTO.
• Does this subject have a major medical illness with life expectancy <2 years or with an unacceptably high operative risk?
• Does this subject have a major neurological deficit that would affect gait?
• Is this subject possibly pregnant or planning pregnancy?
• Is this subject unable to read English?
• Does this subject have a psychiatric illness that limits informed consent?
• Is the subject unlikely to comply with study protocol?