Kinematic Alignment vs Mechanical Alignment for Total Knee Arthroplasty

This is a prospective, randomized, single-blinded, multi-center trial comparing Kinematic Alignment vs Mechanical Alignment in TKA patients using patient reported outcomes, clinical and functional performance tests and radiographic analyses.

This is a prospective, randomized, single-blinded, multi-center trial comparing Kinematic Alignment vs Mechanical Alignment in TKA patients with Medacta GMK Sphere knee system using patient specific instrumentation Medacta MyKnee. Patients will be assessed a pre-operative, operative and interim post-operative visits, week 6, month 6 and 1,2,5 \& 10 years. There will be a phone survey follow up at year 3,4,6,7,8,\& 9.

Eligibility Criteria:
Inclusion Criteria:

* Must be able to read, understand and provide written informed consent on the Institutional Review Board (IRB) approved Informed Consent Form (ICF).

  * Ability to understand and provide written authorization for use and disclosure of personal health information.
  * Subject who are able and willing to comply with the study protocol and follow-up visits.
  * Must be 21 years or older to participate, and less than 80 years old.
  * Subjects must have osteoarthritis knee disease in the affected knee compliant with the FDA-approved indications for use of GMK Sphere knee system and MyKnee cutting blocks.
  * Patients who are candidates for Total Knee Arthroplasty and are determined to undergo a TKA using the Medacta GMK Sphere implant and MyKnee cutting blocks will be offered enrollment.
  * Subjects must be able to return for the follow-up appointments, and have the mental capacity to cooperate and complete PRO questionnaires, physical exam and radiographs.

Exclusion Criteria:

* • Cases of extreme bone loss requiring an augmented femoral or tibial implant and chronic ligamentous laxity requiring a constrained implant

  * The patient has a fixed flexion deformity of ≥15°
  * The patient has less than 90° of flexion
  * Patient is morbidly obese (BMI ≥40)
  * Patient with inflammatory arthritis
  * History of prior deep knee infection
  * History of alcoholism or drug abuse
  * Currently on chemotherapy or radiation therapy for neoplastic disease
  * Patient currently on immunosuppressive medications including steroids except when, (a) steroid use is less than 10mg daily, (b) other immunosuppressive medications are held for appropriate time, for example Adalimumab is held 2 weeks prior and 2 weeks after surgery
  * History of known sensitivity or allergy to materials used in orthopedic implants, specifically Titanium and Cobalt-Chrome alloys
  * Habitual use of narcotic pain medications prior to surgery (more than 2 doses daily and chronic use of a minimum 3 months)
  * History of metabolic disorder affecting the skeletal system other than osteoarthritis or osteoporosis (e.g., Osteomalacia, Ricketts)
  * History of chronic pain issues for reasons other than knee joint pain. If the type of pain affects activities of daily living, do not enroll. If the pain is intermittent and does not affect activities of daily living, it is OK to enroll. Fibromyalgia is exclusionary.
  * Women who are pregnant
  * Patient with unstable psychiatric illness or psychosis is excluded. (Patients with stable anxiety or depression can be enrolled if PI determines that the condition does not adversely affect study outcomes \& requirements)
  * Any patient, in the opinion of the investigator, is unable to fully comply with the surgical, rehabilitation, or follow-up aspects of this procedure.
  * Prior surgery on the target knee other than arthroscopy and/or arthroscopically-assisted ligament reconstruction
  * Prior high tibial osteotomy (HTO) or femoral osteotomy
  * Malunion of fracture of a tibia or femur
  * Patient with a neuromuscular or neurosensory deficiency
  * Patient with history of knee fusion in the affected joint