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Completed

NCT Number: NCT01418378

Sigma CR150 Versus Sigma CR Knee RCT

This study will compare two very similar designs of knee replacement device. One device (Sigma CR150) is a slightly modified version of the original (Sigma CR) and has been modified to enhance/accommodate higher flexion. The original device has been in widespread clinical use with excellent results since 1996 and this study will determine whether the design modifications of the newer device add further value. The newer device has been in clinical use with good short-term(unpublished) outcomes since becoming commercially available in January 2009.

Achieving higher knee flexion may be required for cultural reasons or by the increasingly younger, more active patient population undergoing knee replacement today. In addition to promoting flexion, it is also possible that this design change may help the knee replacement to last longer than traditional implants in patients who achieve higher flexion. Therefore, the study will compare the two devices in terms of survivorship, flexion and other measures of the success of a total knee replacement (range of motion, knee-related quality of life, activity and generic quality of life) over the short-term.

A minimum of one hundred and forty subjects (minimum 70 per group) with osteoarthritis and aged 50-75 years will be included at UK/international hospitals.

Study duration is 2 years and patients will complete standard knee outcome scores plus radiological evaluation.

Subjects would receive one of the study devices regardless of their involvement in the study, and apart from (possible)additional visits, x-rays and/or questionnaires, treatment and follow-up care will be as per the care they would receive outside of the study.

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Key information

Conditions

Osteoarthritis Arthritis Joint Diseases Musculoskeletal Diseases Rheumatic Diseases

Age range

50 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Sunshine Hospitals, Secunderabad, Andhra Pradesh, India

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

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

Inclusion criteria

i)Male or female subjects, aged between 50 and 75 years inclusive.

ii)Subjects who are able to give voluntary, written informed consent to participate in this clinical investigation and from whom consent has been obtained.

iii) Subjects who, in the opinion of the Clinical Investigator, are able to understand this clinical investigation, co-operate with the investigational procedures and are willing to return to the hospital for all the required post-operative follow-ups.

iv) Subjects defined by the Investigator as ASA Grade I or II.

v) Subjects with a primary diagnosis of osteoarthritis.

vi) Subjects who require a primary total knee arthroplasty.

vii) Subjects who can achieve active flexion of 90 degrees.

Exclusion criteria

i) Subjects who, in the opinion of the Clinical Investigator, have an existing condition that would compromise their participation and follow-up in this clinical investigation.

ii) Subjects who are known drug or alcohol abusers or with psychological disorders that could affect follow-up care or treatment outcomes.

iii) Subjects who have participated in a clinical investigation with an investigational product in the last month.

iv) Subjects who are currently involved in any injury litigation claims.

v) Subjects with an anatomical limb alignment of above 20 degrees varus or valgus.

vi) Subjects with a fixed flexion deformity of over 20 degrees.

vii) Subjects with recurvatum (definition: hyperextension ≥ 5 degrees).

viii) Subjects who cannot flex their hip to 90 degrees.

ix) Subjects with a BMI of 35 or above.

x) Subjects defined by the Investigator as ASA Grade III-V.

xi) Subjects who are identified pre-operatively as having bone defects which require augmentation.

xii) Subjects who have previously undergone total or unicondylar knee arthroplasty, high tibial osteotomy, ligament reconstruction, ORIF or with previous fracture in the knee joint.

xiii) Subjects with primary or secondary diagnosis of inflammatory or traumatic arthritis.

xiv) Subjects who have undergone contralateral total knee arthroplasty during the previous 6 months.

xv) Subjects who in the opinion of the Investigator require patellar resurfacing.

Intra-operative exclusion criteria:

i) Subjects who have uncontained bone defects or defects bigger than 8 mm3 and/or require augmentation.

ii) Subjects who are not suitable to receive both the study and comparator devices.

iii) Subjects who require patellar resurfacing

Treatment and study plan

Sigma CR150

Device

Sigma CR150 femoral component used in combination with the Highly Polished Cobalt Chrome fixed bearing tibial tray and the Curved (XLK) polyethylene bearing (cemented, no patellar resurfacing).

Other names: PFC Sigma CR150

Sigma CR

Device

Sigma CR femoral component used in combination with the Highly Polished Cobalt Chrome fixed bearing tibial tray and the Curved (XLK) polyethylene bearing (cemented, no patellar resurfacing).

Other names: PFC Sigma CR

Primary outcomes

  1. Percentage of Knees Who Survived at 2 Years Post-operative

    Time frame: 2 Years

    The Kaplan-Meier success rate at 24-months post-operatively was calculated with Kaplan-Meier time-to-event methodology, where the time variable for patients who were successful (no components revised for any reason) was censored at the time of last follow-up.

Secondary outcomes

  1. Change From Baseline in Goniometer Measured Maximum Passive Flexion at 2 Years

    Time frame: Pre-operative baseline to 2 years

    Comparative evaluation of the change from baseline values in 2 year goniometer-measured passive flexion. A goniometer is an instrument used to measure angles in degrees and captures the change in angle between the upper and lower leg

  2. Knee Injury and Osteoarthritis Outcome Pain Subscore - 1 Year

    Time frame: Pre-operative baseline to 1 year

    Comparative evaluation of the change from baseline values at 1 years in Knee Injury and Osteoarthritis Outcome Pain Subscore

    The subscore ranges from 0 (no pain) to 36 (extreme pain). The subscore is then transformed into a 0 (extreme pain) to 100 (no pain) scale.

    100 - (score x 100) / 36 = transformed score

  3. Knee Injury and Osteoarthritis Outcome Pain Subscore - 2 Years

    Time frame: 2 years

    Comparative evaluation of the change from baseline values at 2 years in Knee Injury and Osteoarthritis Outcome Pain Subscore

    The subscore ranges from 0 (no pain) to 36 (extreme pain). The subscore is then transformed into a 0 (extreme pain) to 100 (no pain) scale.

    100 - (score x 100) / 36 = transformed score

  4. Knee Injury and Osteoarthritis Outcome Symptoms Subscore - 1 Years

    Time frame: 1 years

    Comparative evaluation of the change from baseline values at 1 year in Knee Injury and Osteoarthritis Outcome Symptom Subscore

    The subscore ranges from 0 (no symptoms) to 36 (always have symptoms). The subscore is then transformed into a 0 (always have symptoms) to 100 (never have symptoms) scale.

    100 - (score x 100) / 36 = transformed score

  5. Knee Injury and Osteoarthritis Outcome Symptom Subscore - 2 Years

    Time frame: 2 years

    Comparative evaluation of the change from baseline values at 2 years in Knee Injury and Osteoarthritis Outcome Symptom Subscore

    The subscore ranges from 0 (never have symptoms) to 28 (always have symptoms). The subscore is then transformed into a 0 (always have symptoms) to 100 (never have symptoms) scale.

    100 - (score x 100) / 28 = transformed score

  6. Knee Injury and Osteoarthritis Outcome - Activities of Daily Living Subscore - 1 Years

    Time frame: 1 year

    Comparative evaluation of the change from baseline values at 1 years in Knee Injury and Osteoarthritis Outcome Symptom Subscore

    The subscore ranges from 0 (no difficulty) to 68 (extreme difficulty). The subscore is then transformed into a 0 (extreme difficulty) to 100 (no difficulty) scale.

    100 - (score x 100) / 68 = transformed score

  7. Knee Injury and Osteoarthritis Outcome - Activities of Daily Living Subscore - 2 Years

    Time frame: 2 year

    Comparative evaluation of the change from baseline values at 2 years in Knee Injury and Osteoarthritis Outcome Activities of Daily Living Subscore

    The subscore ranges from 0 (no difficulty) to 68 (extreme difficulty). The subscore is then transformed into a 0 (extreme difficulty) to 100 (no difficulty) scale.

    100 - (score x 100) / 68 = transformed score

  8. Knee Injury and Osteoarthritis Outcome - Sport and Recreation Subscore - 1 Years

    Time frame: 1 year

    Comparative evaluation of the change from baseline values at 1 years in Knee Injury and Osteoarthritis Outcome Activities of Daily Living Subscore

    The subscore ranges from 0 (no difficulty) to 20 (extreme difficulty). The subscore is then transformed into a 0 (extreme difficulty) to 100 (no difficulty) scale.

    100 - (score x 100) / 20 = transformed score

  9. Knee Injury and Osteoarthritis Outcome Sport and Recreation Subscore - 2 Years

    Time frame: 2 year

    Comparative evaluation of the change from baseline values at 2 years in Knee Injury and Osteoarthritis Outcome Activities of Daily Living Subscore

    The subscore ranges from 0 (no difficulty) to 20 (extreme difficulty). The subscore is then transformed into a 0 (extreme difficulty) to 100 (no difficulty) scale.

    100 - (score x 100) / 20 = transformed score

  10. Knee Injury and Osteoarthritis Outcome - Quality of Life Subscore - 1 Years

    Time frame: 1 year

    Comparative evaluation of the change from baseline values at 1 years in Knee Injury and Osteoarthritis Outcome Activities of Quality of life Subscore

    The subscore ranges from 0 (no difficulty) to 16 (extreme difficulty). The subscore is then transformed into a 0 (extreme difficulty) to 100 (no difficulty) scale.

    100 - (score x 100) / 16 = transformed score

  11. Knee Injury and Osteoarthritis Outcome - Quality of Life Subscore - 2 Years

    Time frame: 2 years

    Comparative evaluation of the change from baseline values at 2 years in Knee Injury and Osteoarthritis Outcome Quality of Life Subscore

    The subscore ranges from 0 (no difficulty) to 16 (extreme difficulty). The subscore is then transformed into a 0 (extreme difficulty) to 100 (no difficulty) scale.

    100 - (score x 100) / 16 = transformed score

  12. Change From Baseline in Goniometer Measured Maximum Passive Flexion at 1 Year.

    Time frame: 1 year

    Comparative evaluation of the change from baseline values in 1 year goniometer-measured passive Flexion. A goniometer is an instrument used to measure angles in degrees and captures the change in angle between the upper and lower leg. Passive flexion involves moving the leg through range of motion without active muscle contraction

  13. Change From Baseline in Goniometer Measured Maximum Passive Extension at 1 Year

    Time frame: 1 year

    Comparative evaluation of the change from baseline values in 1 year goniometer-measured passive extension. A goniometer is an instrument used to measure angles in degrees and captures the change in angle between the upper and lower leg. Passive extension involves the leg being moved without active muscle contraction

  14. Change From Baseline in Goniometer Measured Maximum Passive Extension at 2 Years

    Time frame: 2 year

    Comparative evaluation of the change from baseline values in 2 year goniometer-measured passive extension. A goniometer is an instrument used to measure angles in degrees and captures the change in angle between the upper and lower leg. Passive extension involves moving the leg without active muscle contraction

  15. Change From Baseline in Goniometer Measured Maximum Total Range of Motion at 1 Year

    Time frame: 1 year

    Comparative evaluation of the change from baseline values in 1 year goniometer-measured total range of motion. A goniometer is an instrument used to measure angles in degrees and captures the change in angle between the upper and lower leg. Total range of motion is the full distance the lower leg travels in relation to the upper leg.

  16. Change From Baseline in Goniometer Measured Maximum Total Range of Motion at 2 Years.

    Time frame: 2 years

    Comparative evaluation of the change from baseline values in 2 year goniometer-measured total range of motion. A goniometer is an instrument used to measure angles in degrees and captures the change in angle between the upper and lower leg. Total range of motion is the full distance the lower leg travels in relation to the upper leg.

  17. Number of Participants With Flexion Contracture at 1 Year

    Time frame: 1 years

    Summary of flexion contracture at 1 year time point. Flexion contracture is a shortening of the muscles that prevents the leg from fully extending

  18. Number of Participants With Flexion Contracture at 2 Years

    Time frame: 2 years

    Summary of flexion contracture at 2 year time point.Flexion contracture is a shortening of the muscles that prevents the leg from fully extending

  19. Total Knee Society Score at 1 Year

    Time frame: 1 year

    Total Knee Society Knee Score change from baseline at 1 year

    The Total Knee Society Score is comprised of two scores: the Knee Score and the Function Score. Both have a 0-100 range. Sub-scales are combined to compute a total score of 100

    The Total Knee Society Score is made up of pain, range of motion, alignment and stability subscores. An Excellent score is 80-100, a good score is 70-79, a fair score is 60-69 and a poor score is anything below 60.

  20. Total Knee Society Knee Score at 2 Years

    Time frame: 2 years

    Total Knee Society Knee Score change from baseline at 2 years

    The Total Knee Society Score is comprised of two scores: the Knee Score and the Function Score. Both have a 0-100 range. Sub-scales are combined to compute a total score of 100

    The Total Knee Society Score is made up of pain, range of motion, alignment and stability subscores. An Excellent score is 80-100, a good score is 70-79, a fair score is 60-69 and a poor score is anything below 60.

  21. Anatomic Alignment Angle

    Time frame: 1 year time point

    Anatomic angle measured at 1 year time point.

    If one draws a line from the center of the hip joint to the center of the ankle joint this is considered to be the mechanical axis of the femur.

    A line drawn through the center of the femoral shaft is the anatomic axis.

    The angle created at the intersection of these lines is referred to as the anatomic alignment angle.

    A normal angle is approximately 7-9 degrees "valgus" or slightly "knock-kneed". "Varus" angles are less common and are also referred to as "bow-legged".

  22. Anatomic Alignment Angle

    Time frame: 2 year time point

    Anatomic angle measured at 2 year time point.

    If one draws a line from the center of the hip joint to the center of the ankle joint this is considered to be the mechanical axis of the femur.

    A line drawn through the center of the femoral shaft is the anatomic axis.

    The angle created at the intersection of these lines is referred to as the anatomic alignment angle.

    A normal angle is approximately 7-9 degrees "valgus" or slightly "knock-kneed". "Varus" angles are less common and are also referred to as "bow-legged".

  23. Alignment - Femoral Component to Anatomic Angle.

    Time frame: 1 year time point

    Femoral component angle measured at 1 year time point. This angle is measured between a line drawn from the center of the femoral head and a line across the bottom of the femoral implant (condyles).

  24. Alignment - Femoral Component to Anatomic Angle

    Time frame: 2 year time point

    Femoral component angle measured at 2 year time point. This angle is measured between a line drawn from the center of the femoral head and a line across the bottom of the femoral implant (condyles).

  25. Alignment - Tibial Component to Anatomic Angle

    Time frame: 1 year time point

    Tibial component angle measured at 1 year time point. This angle is measured between a line drawn from the center of the femoral head tibial implant.

  26. Alignment - Tibial Component to Anatomic Angle

    Time frame: 2 year time point

    Tibial component angle measured at 2 year time point. This angle is measured between a line drawn from the center of the femoral head tibial implant.

  27. Alignment - Femoral Component Flexion

    Time frame: 1 year time point

    Femoral Component Flexion measured at 1 year time point. This measures the angle between a line drawn though the center of the side of the femur and a line drawn across the top of the flat inner surface of the femoral component.

  28. Alignment - Femoral Component Flexion

    Time frame: 2 year time point

    Alignment - Femoral Component Flexion measured at 2 year time point. This measures the angle between a line drawn though the center of the side of the femur and a line drawn across the top of the flat inner surface of the femoral component.

  29. Alignment - Tibial Posterior Slope

    Time frame: 1 year time point

    Tibial Posterior Slope measured at 1 year time point. This angle is measured between a line through the center of the side of the tibia and the top flat surface of the tibial implant

  30. Alignment - Tibial Posterior Slope

    Time frame: 2 year time point

    Alignment - Tibial Posterior Slope measured at 2 year time point. This angle is measured between a line through the center of the side of the tibia and the top flat surface of the tibial implant

  31. Number of Subjects With Radiolucencies - Femoral Component

    Time frame: 6 to 12 week and 24 month intervals

    The bone-implant interface at the femoral components were examined radiographically and radiolucencies were measured in millimeters.

    Radiolucent lines (RLLs) greater than 2mm are considered to be clinically significant.

  32. Number of Subjects With Radiolucencies - Tibial Component

    Time frame: 6 weeks to 24 months

    The bone-implant interface at the tibial components were examined radiographically and radiolucencies were measured in millimeters.

    Radiolucent lines (RLLs) greater than 2mm are considered to be clinically significant.

    Radiolucent lines greater than 2mm are considered to be clinically significant.

  33. Radiographic Evaluation of Maximum Flexion

    Time frame: 1 year time point

    Maximum knee flexion measured radiographically at 1 year time point

Sponsors and collaborators

Lead sponsor

DePuy International

Industry

Registry information

Official study title

A Double-blinded Randomised Controlled Trial Comparing the Performance of the Sigma® CR150 and Sigma® CR Knee Systems, When Used in Fixed Bearing Primary Cruciate Retaining Total Knee Arthroplasty for the Treatment of Osteoarthritis

Important dates

Study start
2011
Primary completion
2016
Study completion
2016
First posted
Aug 17, 2011
Registry last updated
Aug 28, 2019

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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