Functionally Aligned vs Mechanical Axis Aligned Total Knee Arthroplasty

Not Applicable

• Conditions: Osteoarthritis; Osteo Arthritis Knee
• Interventions: Procedure: Mechanically Aligned Total Knee Arthroplasty; Procedure: Functionally Aligned Total Knee Arthroplasty

• Registration Number: NCT04748510
• Lead Sponsor: Perth Hip and Knee

Brief 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). Both FA TKA and MA TKA are performed through similar skin incisions, robotic-guidance, and use identical implants. In MA TKA, bone is prepared and implants positioned to ensure that that the overall alignment of the leg is in neutral. In FA TKA, the bone is prepared and implants positioned to restore the natural alignment of the patient's leg. Both of these surgical techniques provide excellent outcomes in TKA but it is not known which of the two techniques is better for patient recovery. Mako robotic-assisted TKA is an established treatment for arthritis of the knee joint. The positions of the implants and overall alignment of the leg are important as they influence how quickly the implants wear out and need replacing. The aim of this study is 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)

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-02-04
• Study First Submitted QC: 2021-02-08
• Study First Posted: 2021-02-10
• Study Start: 2021-04-30
• Status Verified: 2022-04
• Last Update Submitted: 2022-04-28
• Last Update Posted: 2022-04-29
• Primary Completion: 2023-08
• Study Completion: 2024-02

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 100

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 therapy's 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 principal.
• Patient has bone loss that requires augmentation
• Patient requires revision surgery following previously failed correctional osteotomy or ipsilateral TKA (eg. 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 on 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 (eg. Dementia)
• Patient is unable to communicate effectively in English.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Mechanical axis aligned Total Knee Arthroplasty	Mechanically Aligned Total Knee Arthroplasty	Knee arthroplasty performed using a mechanical alignment theory
Functionally aligned Total Knee Arthroplasty	Functionally Aligned Total Knee Arthroplasty	Knee arthroplasty performed using a functional alignment theory

Primary Outcome Measures

Name	Time	Method
Difference in Oxford Knee Score after 2 years	Preoperatively and 2 years postoperatively	Difference in relative change in Oxford Knee Score (OKS) between FA and MA patients 2 years post-operatively compared to preoperatively. Scale 0-48 with higher scores being a better outcome.
Difference in Forgotten Joint Score after 2 years	Preoperatively and 2 years postoperatively	Difference in relative change in Forgotten joint score between FA and MA patients 2 years post-operatively compared to preoperatively. Scale 0-100 with higher scores being a better outcome
Relative change in range of motion between FA and MA patients post-operatively compared to preoperatively.	Preoperatively and 2 years postoperatively	Difference in range of motion via goniometry preoperatively and postoperatively at 2 years

Secondary Outcome Measures

Name	Time	Method
Difference in clinical outcomes as measured in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement Score (KoosJR)	Measured Pre-operatively and at 3 month, 1 year and 2 years post operatively.	Difference in operated knee outcome on Koos JR scale. Scale 0-100 where higher scores mean better outcome.
Determine lower limb alignment achieved with both alignment techniques	3 Months post-operatively	Lower limb alignment as assessed using standing long leg x-rays performed postoperatively at 3 months. Measurements of the hip-knee-angle (HKA), medial proximal tibial angle (MPTA) and lateral distal femoral angle (LDFA). Also evidence of imbalance with implant lift off will be measured.
Difference in analgesia requirements between patients in alignment groups	6 weeks, 3 months, 1 year, 2 years	Determine if there are any differences in analgesic requirements based on alignment method used.; Inpatient medical records will be utilised to obtain analgesia requirements as inpatient Questionnaires will be used to obtain analgesia usage at remaining timepoints. Analgesia usage will be converted to morphine equivalent dosages for comparison
Difference in sagittal stability of the knee post replacement	Preop, and post-operatively at 3 months, 1 year and 2 years	Determine whether alignment method utilized has an effect on the sagittal stability of the knee post replacement, as measure with an arthrometer "Lachmeter"
Difference in functional outcomes (measured as maximal voluntary contraction) of knee flexion and extension between alignment groups	Preop, 3 months, 1 Year and 2 years	Determine whether alignment method utilized has an effect on functional outcomes.; Measured as Maximal voluntary isometric knee flexion and extension forces as measured via hand-held dynamometry.
Intra-operative balance achieved with different alignment techniques.	Intraoperatively	Surgeon blinded measurement of intraoperative balance achieved with Verasense sensor (smaller cohort) Secondary outcome \[6\] To determine if there is a difference in knee kinematics between the two techniques. Measurement of knee kinematics with Verasense sensor to assess presence or absence of medial pivot (smaller cohort)
Difference in clinical outcomes as measured in European Quality of Life questionnaire with 5 dimensions for adults (EQ-5D-5L).	Measured Pre-operatively and at 3 month, 1 year and 2 years post operatively.	Difference in overall by Visual Analogue Scale for overall health (VAS). Scale: Five dimensions combined into a 5-digit number lower numbers represent better outcomes. Addition of overall health VAS Scale 0-100 with higher score being better outcome.
Difference in operated knee pain as measured by Visual Analogue Scale for pain (VAS)	Measured Pre-operatively and at 3 month, 1 year and 2 years post operatively.	Difference in operated knee pain as measured by Visual Analogue Scale for pain (VAS). Scale 0-100 with higher scores meaning worse outcome.
Difference in clinical outcomes as measured by Kujala score- a measure of anterior knee pain and best clinical score for patellofemoral function	Measured Pre-operatively and at 3 month, 1 year and 2 years post operatively.	Difference in clinical outcomes as measured by Kujala score. Scale 0-100 with higher scores meaning better outcome.

Trial Locations

Locations (2)

St John of God Private Hopsital; 🇦🇺 Subiaco, W, Australia

Perth Hip and Knee; 🇦🇺 Subiaco, Western Australia, Australia