Patellar Resurfacing Versus Patellar Retention in Total Knee Arthroplasty - A Randomized Clinical Trial

NCT01500252 | Completed Phase 4 Results

• 1 other identifier: Pro00002794
• Study Type: interventional
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

Background: Despite the excellent results of total knee replacement, also known as total knee arthroplasty (TKA) there is persistent controversy over whether or not to replace the surface of the kneecap. Anterior knee pain, which occurs with variable and unpredictable frequency, continues to be a problem in a subset of TKA patients. Some clinicians replace the surface of all kneecaps during TKA to avoid repeat surgery, which occurs in approximately 10% of cases. However, others cite the complications attributed to replacing the surface of kneecap as reasons to avoid this procedure. This study prospectively randomized patients receiving TKA into two groups, those receiving replacement of the kneecap surface and those left without replacement of the kneecap surface to determine clinical outcomes and revisions over the first 5-10 postoperative years. Objectives: The primary objective of this work was to compare pain, stiffness and function between groups at five years postoperatively. Secondarily, we compared pain, stiffness and function at one and 10 years postoperatively. Finally, we examined the number of reoperations following TKR over 10 years in the 2 groups of subjects. The investigators hypothesized that there would be no difference between the two groups of subjects in the measured outcomes. Methods: Patients receiving TKA were prospectively enrolled before surgery and randomized intraoperatively to either receive a replacement of the kneecap surface or have no kneecap intervention. The Smith and Nephew Profix TKA system was implanted in all cases; the post-operative regimen was standardized. Subjects were assessed pre-operatively and at 1 and 5 years postoperatively for pain, function, and stiffness using a disease-specific (Western Ontario and MacMaster Osteoarthritis Index \[WOMAC\]) and generic health status (Short Form 36 \[SF-36\]) questionnaire. At the end of the five year follow-up, the study was extended to a 10-year followup and the same outcomes were assessed. The revision rate was also compared between the two groups at the end of the 10-year follow-up.

Conditions

Total Knee Replacement

Keywords

Total Knee Replacement; Patellar Resurfacing; Health Related Quality of Life

Outcome Measures

Primary Outcomes (3)

• Change in Western Ontario MacMaster (WOMAC) Osteoarthritis Index Pain Score From Preoperative to 5 Years Postoperative

  This index assesses pain as reported by the patient. The WOMAC Pain scale has a minimum value of 0 (worst pain) to a maximum value of 100 (no pain). The change score was calculated by subtracting the preoperative score from the five year score.

  Preoperative to 5 years postoperative

• Change in WOMAC Osteoarthritis Index Function Score From Preoperative to 5 Years Postoperative

  This measures the change in patients' reported function from preoperative to 5 years postoperative. The WOMAC Function scale has a minimum value of 0 (worst function) to a maximum value of 100 (no functional limitations). The change score was calculated by subtracting the preoperative score from the five year score.

  Preoperative to 5 years postoperative

• Change in WOMAC Osteoarthritis Index Stiffness Score From Preoperative to 5 Years Postoperative

  This is the change in the patients' perceived pain between preoperative and 5 years postoperative. The WOMAC stiffness scale has a minimum value of 0 (maximal stiffness) to a maximum value of 100 (no stiffness). The change score was calculated by subtracting the preoperative score from the five year score.

  Preoperative to 5 years postoperative

Secondary Outcomes (7)

• Change in WOMAC Osteoarthritis Index Pain Score From Preoperative to 1 Year Postoperative

  Preoperative to 1 year postoperative

• Change in WOMAC Osteoarthritis Index Function Score From Preoperative to 1-year Postoperative

  Preoperative to 1 year postoperative

• Change in WOMAC Osteoarthritis Index Stiffness Score From Preoperative to 1 Year Postoperative

  Preoperative to 1 year postoperative

• Change in WOMAC Osteoarthritis Index Pain Score From 5 Years Postoperative to 10 Years Postoperative

  5 years postoperative to 10 years postoperative

• Change in WOMAC Osteoarthritis Index Function Score From 5 Years Postoperative to 10 Years Postoperative

  5 years postoperative to 10 years postoperative

Study Arms (2)

Patellar Resurfacing

EXPERIMENTAL

These subjects received a Profix TKR including an all polyethylene patellar implant.

Device: Patellar Replacement Prosthesis

Patellar Retention

ACTIVE COMPARATOR

This group received a Profix TKR, but retained their native patella

Device: Profix TKR with Patellar Retention

Interventions

Patellar Replacement Prosthesis DEVICE

The Profix™ Total Knee System, a posterior cruciate retaining prosthesis manufactured by Smith and Nephew, Inc. was utilized in all subjects. Subjects randomized to the Resurfaced group received an all polyethylene patellar implant

Patellar Resurfacing

Profix TKR with Patellar Retention DEVICE

All subjects received a Profix TKR. Subjects in the Patellar Retention group retained their native patellar surface.

Patellar Retention

Eligibility Criteria

• Age: 40 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• scheduled for primary TKA to treat non-inflammatory arthritis
• age 40- 75 years of age

You may not qualify if:

• history of knee sepsis
• previous patellectomy
• previous high tibial osteotomy
• knee flexion contracture of \>20 degrees
• varus or valgus deformity of \> 20 degrees
• \< 90 degrees of knee flexion
• tibial or femoral bone deficiency requiring augmentation

Sponsors & Collaborators

• University of Alberta: lead
• Smith & Nephew, Inc.: collaborator

Study Sites (1)

University of Alberta Hospital

Edmonton, Alberta, T6G 2B7, Canada

Location

Related Publications (1)

• Beaupre L, Secretan C, Johnston DW, Lavoie G. A randomized controlled trial comparing patellar retention versus patellar resurfacing in primary total knee arthroplasty: 5-10 year follow-up. BMC Res Notes. 2012 Jun 7;5:273. doi: 10.1186/1756-0500-5-273.

  PMID: 22676495 DERIVED

Results Point of Contact

• Title: Dr. Lauren Beaupre
• Organization: UAlberta

lauren.beaupre@albertahealthservices.ca

780-407-3945

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 22, 2011
• First Posted: December 28, 2011
• Study Start: September 1, 1996
• Primary Completion: June 1, 2004
• Study Completion: December 1, 2009
• Last Updated: July 27, 2021
• Results First Posted: May 1, 2012

Record last verified: 2021-07

Locations

CA (1)