A Study to Compare the NexGen CR and CR-Flex Knee Implants

Zimmer Biomet

Status

Completed

Conditions

Osteoarthritis

Total Knee Arthroplasty

Treatments

Device: NexGen CR-Flex Fixed Bearing Knee

Device: NexGen CR Knee

Study type

Interventional

Funder types

Industry

Identifiers

NCT00761956

04-300

Details and patient eligibility

About

The purpose of this study is to test for significant differences in functional outcomes, specifically pre-operative ROM and post-operative ROM obtained by using a NexGen CR versus a NexGen CR-Flex knee implant. Specifically, it is predicted that an increase in post-operative range of motion will be experienced by patients treated with the NexGen CR-Flex knee implant.

Full description

This study will compare the clinical results of the NexGen CR femoral component with the higher flexion potential of the NexGen CR-Flex femoral component in all patients with degenerative joint disease that require total knee arthroplasty. The primary variable of interest is post-operative range of motion achieved with the two devices, which are implanted with slightly different surgical techniques in patients who may also be subjected to different rehabilitation programs depending on the device they are assigned.

Enrollment

189 patients

Sex

All

Ages

21 to 80 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Age, 21-80 years
Sex, Male and Females will be included
BMI less than or equal to 39
Stable Health, the patient would be able to undergo surgery and participate in a follow-up program based on physical examination and medical history.
Patient is willing and able to cooperate in follow-up therapy.
Patient exhibits pre-operative radiographic evidenced of joint degeneration consistent with TKA that cannot be treated in non-operative fashion.
Patient has stable and functional posterior cruciate and collateral ligaments.
Patient has potential to perform higher than average range of motion activities.
Operative side range of motion flexion greater than or equal to 120 degrees.
Severe knee pain and disability due to degenerative joint disease.
Patient or patient's legal representative has signed the Informed Consent form.

Exclusion criteria

Previous history of infection in the affected joint.
Previously failed knee endoprosthesis of any kind.
Charcot joint disease or other severe neurosensory deficits.
Previous patellectomy
Patient is skeletally immature.
Grossly insufficient femoral or tibial bone stock.
Patient is pregnant.
Varus or valgus deformity greater than 20 degrees.
Fixed flexion deformity greater than 15 degrees.
Previous high tibial osteotomy.
Previous femoral osteotomy.
Patient is a poor compliance risk, currently treated for ethanol or drug abuse, physical or mental handicap, etc.
Loss of musculature or absence of musculoligamentous supporting structures required for adequate soft tissue balance.