Clinical trial NCT00761956: A Study to Compare the NexGen CR and CR-Flex Knee Implants
Official title: Prospective Randomized Multicenter Study of NexGen CR-Flex Knee
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Total Knee Arthroplasty
Osteoarthritis
Keywords: Total Knee Arthroplasty
Osteoarthritis
Knee
Lead sponsor: Zimmer Biomet
Sponsor class: INDUSTRY
First posted: 2008-09-30
Enrollment: 189
Sex: ALL
Minimum age (years): 21
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: 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.

Detailed 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.

Eligibility criteria: 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.

Primary outcomes:
measure: Postoperative Range of Motion (ROM)
timeFrame: 24 Months
Secondary outcomes:
measure: Return to Function (RtF) Via Knee Scoiety Score (Modified)
timeFrame: 24 Months
Other outcomes:
Locations:
city: Milford
country: United States
facility: Dickinson Medical Group, LLC
state: Delaware
city: Chicago
country: United States
facility: University of Chicago Hospital
state: Illinois
city: Rockford
country: United States
facility: Rockford Orthopedic Associates
state: Illinois
city: Worcester
country: United States
facility: University of Massachusetts Memorial Medical Center
state: Massachusetts
city: Grand Rapids
country: United States
facility: Orthopaedic Associates of Grand Rapids, PC
state: Michigan
city: Pinehurst
country: United States
facility: Pinehurst Surgical Center
state: North Carolina
city: Eugene
country: United States
facility: Slocum Orthopedics, PC
state: Oregon
city: Clairton
country: United States
facility: The Orthopedic Group
state: Pennsylvania
Study officials:
References: