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Active, Not Recruiting

NCT Number: NCT04600583

A Trial of Mechanical Axis With Soft Tissue Release Balancing vs Functional Alignment With Bony Release Balancing in Total Knee Replacement Using Stryker's Mako Robot

This study is a prospective, randomized, longitudinal study of the clinical outcomes of osteoarthritis patients treated by two different alignment philosophies for total knee replacement. All patients will be treated with the same knee system, implanted using MAKO robotic-arm assisted technology.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

Osteoarthritis Arthritis Joint Diseases Musculoskeletal Diseases Rheumatic Diseases

Age range

40 year–80 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

North Shore Hospital

Takapuna, Auckland, 0622, New Zealand

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • The patient is a male or non-pregnant female between the ages of 40-80 years.
  • The patient requires a primary total knee replacement and is indicated for robotic-assisted surgery.
  • Patient is deemed appropriate for a cruciate retaining knee replacement.
  • The patient has a primary diagnosis of osteoarthritis (OA).
  • The patient has intact collateral ligaments.
  • The patient is able to undergo CT scanning of the affected limb.
  • The patient has signed the study specific, ethics-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 previous osteotomy around the knee.
  • 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 deformity ≥ 15°.
  • 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.
  • 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).

Treatment and study plan

Triathlon® Total Knee System (Stryker Orthopaedics, Mahwah, NJ USA)

Device

All patients, regardless of the alignment arm they are randomized to will undergo a primary total knee arthroplasty with the Triathlon® Total Knee System using Mako Robotic-Arm Assisted Technology. The surgical intervention will be administered by a physician wherein the expected duration of surgery is approximately 1.5 hours.

Primary outcomes

  1. Joint feeling and Forgotten Joint Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months (primary timepoint) and 24 months

    To evaluate differences in joint feeling assessed via the Forgotten Joint Score. This newly-developed 12-item score ranges from 0 to 100 and assesses how aware recipients are of their joint in everyday life. Higher scores indicate a good outcome i.e. a high degree of forgetting the joint. For the purpose of this study a change in score of 14 points for the Forgotten Joint Score has been identified.

Secondary outcomes

  1. Function and Oxford Knee Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: Oxford Knee Score. This score ranges from 0 to 48 where a higher score indicates a better outcome.

  2. Function and The International Knee Society Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 12 months and 24 months

    To evaluate differences in function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: The International Knee Society Score. This score ranges from 0 to 100 where a higher score correlates to a better outcome.

  3. Function and Knee Injury and Osteoarthritis Outcome Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: Knee Injury and Osteoarthritis Outcome Score. This score ranges from 0 to 100 where 0 indicates the worst possible knee symptoms and 100 signifies no knee symptoms.

  4. Pain and Oxford Knee Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in pain between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: Oxford Knee Score. This score ranges from 0 to 48 where a higher score indicates a better outcome.

  5. Pain and The International Knee Society Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 12 months and 24 months

    To evaluate differences in pain between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: The International Knee Society Score. This score ranges from 0 to 100 where a higher score correlates to a better outcome.

  6. Pain and Knee Injury and Osteoarthritis Outcome Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in pain between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: Knee Injury and Osteoarthritis Outcome Score. This score ranges from 0 to 100 where 0 indicates the worst possible knee symptoms and 100 signifies no knee symptoms.

  7. Pain and Visual Analogue Scale

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in pain between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following graphic measurement instrument: Visual Analogue Scale. This scale is a continuum between no pain and the worst possible pain imaginable.

  8. Satisfaction and Net Promoter Score

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in satisfaction between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: Net Promoter. This score ranges from -100 to 100 where the upper end indicates the patient's recommendation of the healthcare they received.

  9. Health related quality of life and Euro-Qol (EQ-5D-3L)

    Time frame: Pre-operative (2 weeks prior to surgery), Post-operative - 6 weeks, 6 months, 12 months and 24 months

    To evaluate differences in health-related quality of life between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This will be achieved by employing the following instrument: Euro-Qol (EQ-5D-3L). This score ranges from 0 to 100 where 0 correlates to the worst imaginable health state whilst 100 indicates the best.

  10. Early pain

    Time frame: In-patient setting (< 5 days post-operation), Post-operative - 6 weeks and 6 months

    To evaluate differences in early pain (i.e. from in-patient setting to 6-months post operation) between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved through the use of a patient pain inventory form.

  11. Early function

    Time frame: In-patient setting (< 5 days post-operation)

    To evaluate differences in early function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved by utilizing functional tests conducted by physiotherapists. The following functional test will be carried out on the knee joint: Range of motion

  12. Early function

    Time frame: In-patient setting (< 5 days post-operation)

    To evaluate differences in early function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved by utilizing functional tests conducted by physiotherapists. The following functional test will be employed: 9 step stair climb

  13. Early function

    Time frame: In-patient setting (< 5 days post-operation)

    To evaluate differences in early function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved by utilizing functional tests conducted by physiotherapists. The following functional test will be employed: fast paced 10m walk test

  14. Early function

    Time frame: In-patient setting (< 5 days post-operation)

    To evaluate differences in early function between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved by utilizing functional tests conducted by physiotherapists. The following functional test will be employed: 30 second chair stand test

  15. Blood loss

    Time frame: Intra-operative

    To compare blood loss between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved through obtaining surgical data.

  16. Adjustments to balance

    Time frame: Intra-operative

    To compare adjustments to balance between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This objective will be achieved through obtaining the position from the Robotic system.

  17. Ability to reach target knee balance as assessed by alignment angles and gaps

    Time frame: Pre-operative (2 weeks prior to surgery), intra-operative, Post-operative - 6 weeks, 12 months and 24 months

    To compare the ability to achieve soft tissue balance between Robotic Assisted Functional Alignment and Robotic Assisted Mechanical Alignment. This object will be achieved by comparing pre-operative plan and pre-resection gaps with the final surgical plan and implanted gaps as derived from the robotic system. The implant position is defined as the angulation of components and resected bone in each anatomical plane. The soft tissue balance is defined as gaps created in extension and 90° of flexion when stressing the medial compartment (medial collateral ligament) and lateral compartment (lateral collateral ligament). The overall limb alignment is assessed by comparing the Hip-Knee-Ankle angle from pre-operative to 1-year post-operative on a long leg weight bearing x-ray.

Sponsors and collaborators

Lead sponsor

Stryker South Pacific

Industry

Registry information

Official study title

A Prospective, Randomized, Controlled Trial of Mechanical Axis With Soft Tissue Release Balancing vs Functional Alignment With Bony Release Balancing in Total Knee Replacement - A Study Using Stryker Mako Robotic-Arm Assisted Technology®.

Important dates

Study start
2020
Primary completion
2023
Study completion
2025
First posted
Oct 23, 2020
Registry last updated
Jul 23, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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