Stryker Triathlon Total Knee System for Total Knee Arthroplasty Implanted Using Shapematch Cutting Guides:Sub-Study A

Not Applicable

Completed

Brief Summary: This is a prospective, non-randomized, study of the clinical outcomes of participants that receive the Stryker Triathlon® Total Knee System for Total Knee Arthroplasty implanted using ShapeMatch® Cutting Guides.

Detailed Description: This is a prospective, non-randomized, study of the clinical outcomes of participants that receive the Stryker Triathlon® Total Knee System for Total Knee Arthroplasty implanted using ShapeMatch® Cutting Guides. Sub-study A aims to quantify the reproducibility of intra-operatively positioning the cutting guides onto the affected femoral and tibial joint surfaces.

Recruitment & Eligibility

Inclusion Criteria

The patient is a male or non-pregnant female between the ages of 50-90.
The patient requires a primary total knee replacement and is indicated for computer-assisted surgery.
The patient has a primary diagnosis of osteoarthritis (OA).
The patient has intact collateral ligaments.
The patient is able to undergo MRI scanning of the affected limb.
The patient has signed the study specific, HREC-approved, Informed Consent document.
The patient is willing and able to comply with the specified pre-operative and post-operative clinical and radiographic evaluations.

Exclusion Criteria

The patient has a history of total, unicompartmental reconstruction or fusion of the affected joint.
The patient has had a high tibial osteotomy or femoral osteotomy.
The patient is morbidly obese (BMI ≥ 40).
The patient has a deformity which will require the use of stems, wedges or augments in conjunction with the Triathlon Total Knee System.
The patient has a varus/valgus malalignment ≥ 15° (relative to mechanical axis).
The patient has a fixed flexion deformity ≥ 15°.
The patient has a neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device.
The patient has a systemic or metabolic disorder leading to progressive bone deterioration.
The patient is immunologically suppressed or receiving steroids in excess of normal physiological requirements.
The patient has a cognitive impairment, an intellectual disability or a mental illness.
The patient is pregnant.
The patient has metal hardware present in the region of the hip, knee or ankle (as this is known to create geometrical distortion in the region of the implant).
The patient has any known contraindications for undergoing assessment by MRI (e.g. ferrous implants, metallic clips, magnetically activated implanted devices such as cardiac pacemakers, etc).

Arm && Interventions

Group	Intervention	Description
Shapematch Cutting Guides	Shapematch Cutting Guides	The ShapeMatch® Cutting Guides are intended to be used as patient-specific surgical instrumentation to assist in the positioning of knee arthroplasty components intra-operatively and in guiding the marking of bone before cutting. They are intended for single use only.

Primary Outcome Measures

Name	Time	Method
Repeatability of Cutting Guide Position	Intraoperative - participants were followed for the duration of the operation, an average of 1 hour and 50 minutes.	Repeatability of cutting guide position on the distal femur and proximal tibia assessed by repeated measures using computer navigation system for total knee replacement, assessed intra-operatively. Placement of the cutting guides by the surgeon was determined by recording the position of the cutting guide when placed by the same surgeon multiple times. The intraclass correlation coefficient (ICC) was calculated for each positioning parameter. This included femoral and tibial varus/valgus,flexion/extension, medial resection, lateral resection and rotation. ICC agreement categories:\>0.75 excellent agreement; 0.75-0.4 good or fair agreement; \<0.4 poor agreement.

Secondary Outcome Measures