N/A Completed N=100 Randomized Double-blind Treatment

Functionally Aligned vs Mechanical Axis Aligned Total Knee Arthroplasty

Osteoarthritis · Osteo Arthritis Knee

Source: ClinicalTrials.gov NCT04748510 ↗

Enrolled (actual)

100

Serious AEs

2.0%

Results posted

Aug 2025

Primary outcomePrimary: Change in Forgotten Joint Score After 2 Years From Baseline — 50.1; 46.4 score on a scale

Summary

The objective of this study is to compare clinical and radiological outcomes in robotic-arm assisted TKA using mechanical alignment (MA TKA) versus robotic-arm assisted TKA with functional alignment (FA TKA). These outcomes will be used to determine if patient recovery is better with functionally aligned Mako robotic-assisted total knee arthroplasty (FA TKA) or mechanically aligned Mako robotic-assisted total knee arthroplasty (MA TKA).

Outcome Measures

Outcome	Result	p-value
PRIMARY Change in Forgotten Joint Score After 2 Years From Baseline	50.1; 46.4	—
PRIMARY Change in Oxford Knee Score After 2 Years From Baseline	17.0; 17.2	—
PRIMARY Change in Range of Motion After 2 Years From Baseline	2.8; 2.8	—
SECONDARY Determine Lower Limb Alignment Achieved With Both Alignment Techniques	—	—
SECONDARY Difference in Analgesia Requirements Between Patients in Alignment Groups	—	—
SECONDARY Difference in Sagittal Stability of the Knee Post Replacement	—	—
SECONDARY Difference in Functional Outcomes (Measured as Maximal Voluntary Contraction) of Knee Flexion and Extension Between Alignment Groups	—	—
SECONDARY Intra-operative Balance Achieved With Different Alignment Techniques.	—	—
SECONDARY Difference in Clinical Outcomes as Measured in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement Score (KoosJR)	—	—
SECONDARY Difference in Clinical Outcomes as Measured in European Quality of Life Questionnaire With 5 Dimensions for Adults (EQ-5D-5L).	—	—
SECONDARY Difference in Operated Knee Pain as Measured by Visual Analogue Scale for Pain (VAS)	—	—
SECONDARY Difference in Clinical Outcomes as Measured by Kujala Score- a Measure of Anterior Knee Pain and Best Clinical Score for Patellofemoral Function	—	—

Eligibility Criteria

Inclusion Criteria

Patient has symptomatic knee osteoarthritis requiring primary TKA
Patient and surgeon are in agreement that TKA is the most appropriate treatment
Patient is fit for surgical intervention following review by surgeon
Patient is between 45-75 years of age at time of surgery, computer literate, and able to complete patient-reported outcome measures independently.
Patient must be capable of giving informed consent and agree to comply with the postoperative review program.
Patient must be a permanent resident in an area accessible to the study site
Patient must have sufficient postoperative mobility to attend follow-up clinics and allow for radiographs to be taken
Patient has tried non-pharmacologic therapies including: patient education, self-management programs, aerobic exercise, weight loss, physiotherapy and occupational therapy
Patient has tried appropriate pharmacologic therapies including: regular paracetamol and NSAIDS if appropriate

Exclusion Criteria

Patient is not suitable for routine primary TKA. E.g., patient has ligament deficiency that requires a constrained prosthesis
Interoperative requirement for a more constrained implant.
Intraoperative requirement for the Posterior Cruciate Ligament to be released. These patients will be still included in the study, but analyzed with an intention-to-treat principle.
Patient has bone loss that requires augmentation
Patient requires revision surgery following previously failed correctional osteotomy or ipsilateral TKA (e.g., post-high tibial or distal femoral osteotomy)
Patient requires a polyethylene inset of 13mm or greater.
Patient is immobile or has another neurological condition affecting musculoskeletal function
Patient is less than 44 years of age or greater than 76 years of age
Patient is a compensable patient. I.e., Worker's compensation claim or motor vehicle accident.
Patient is already enrolled in another concurrent clinical trial
Patient is unable or unwilling to sign the informed consent form specific to this study
Patient is unable to attend the follow-up program
Patient is non-resident in local area or expected to leave the catchment area postoperatively
Patients who lacks capacity to provide consent, or the ability to understand the study protocol due to a cognitive condition (e.g., Dementia)
Patient is unable to communicate effectively in English.

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT04748510). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication. Informational only — not medical advice.