None listed
Conditions
Brief summary
Traditionally the goal of the knee replacement has been to position the components such that the alignment goal is a straight limb, or a mechanical axis of 0 degrees. This has been considered desirable from an engineering point of view to maximise implant longevity, however patient satisfaction of total knee replacement has not always been ideal. The opportunity exists to provide an alternative approach to total knee replacement surgery which may improve patient outcomes. One such approach is to determine the optimal placement of components based on the individual anatomy of patients, rather than a generic limb alignment philosophy. A three-dimensional description of the anatomy can be obtained by magnetic resonance imaging (MRI) scans obtained pre-operatively. It is then possible to develop a model of the arthritic bone and cartilage, adapt that model to take into account degenerative processes, and generate a model of the pre-arthritic anatomy. The pre-arthritic state then becomes the surgical goal in terms of limb alignment. Custom cutting guides are generated for each individual patient to enable the surgeon to perform the bone resections in such a way that the resultant construct with the total knee replacement components reproduces the pre-disease limb alignment. The aim of the study is to observe whether there is any difference in outcome following a total knee replacement in terms of pain and function at early follow-up (6 weeks, 6 months and 12 months) between the ShapeMatch Cutting Guide group and the control group. Radiographic, pain, function and health-related quality of life will be compared between both groups using various questionnaires which patients will complete prior to the operation and at 6 weeks, 6 months and 12 months following their total knee replacement. The study will also aim to compare the cost-effectiveness and cost-utility of the procedure between the ShapeMatch group and the Navigation group by recording and calculating various parameters including total duration of operating procedure and length of stay in hospital following the operation.
Interventions
For patients requiring a total knee replacement a new method has been developed which may improve patient satisfaction levels in terms of function and pain after surgery. Instead of using conventional measuring and cutting equipment and computer-assisted navigation (Control Group), patient-specific cutting guides will be manufactured based on pre-operative Magnetic Resonance Imaging (MRI) scans of the patient's leg (Intervention Group). The patient will have a total knee replacement performed
For patients requiring a total knee replacement a new method has been developed which may improve patient satisfaction levels in terms of function and pain after surgery. Instead of using conventional measuring and cutting equipment and computer-assisted navigation (Control Group), patient-specific cutting guides will be manufactured based on pre-operative Magnetic Resonance Imaging (MRI) scans of the patient's leg (Intervention Group). The patient will have a total knee replacement performed using these cutting guides which will ultimately align the patient’s prosthesis according to their natural leg alignment (as opposed to the convention way where the patient’s leg is aligned according to a mechanical axis of 0 degrees). The procedure will take approximately 45 minutes. Both groups will receive the same type of implant. Patients will be followed up at 6 weeks, 6 months and 12 months and also have a Computed Tomography (CT) scan at 3 months.
Sponsors
Stryker Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used)
Eligibility
Sex/Gender
All
Age
40 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
- The patient is a male or non-pregnant female between the ages of 50-80. - 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. - Patient has had a high tibial osteotomy or femoral osteotomy. - The patient is morbidly obese (BMI is greater than or equal to 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 varus or valgus malalignment greater than or equal to 15 degrees (relative to mechanical axis). - The patient has a fixed flexion deformity greater than or equal to 15 degrees. - 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. - 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).
Outcome results
None listed