Comparison of Removing and Non-removing Patellofemoral Joint Osteophytes Following Medial Unicompartment Knee Arthroplasty

Does Removing Patellofemoral Joint Osteophytes Reduce Anterior Knee Pain Following Unicompartment Knee Arthroplasty?

Background: Anterior knee pain (AKP) is a challenge following unicompartmental knee arthroplasty (UKA). Some surgeons remove patellofemoral joint (PFJ) osteophytes to reduce osteophyte impingement and AKP. However, there is evidence that PFJ osteophytes compensate for knee osteoarthritis (OA) by increasing and improving stability and increase contract surface area in knee osteoarthritis. Moreover, when PFJ osteophytes are not removed, some studies report good clinical outcomes. The issue of removing or leaving PFJ osteophytes is controversial.

The objective of this study was to compare AKP following mobile bearing UKA after removing or leaving PFJ osteophytes.

Methods: The prospective non-randomized study included 89 isolated medial osteoarthritis (OA) of knee. They were classified into 2 groups. Group (Gp)1 was removing PFJ osteophytes; consists of 44 knees. Gp2 was non-removing PFJ osteophytes: consists of 45 knees. The patients were follow up and recorded incidence of AKP and VAS for AKP at 6 weeks, 3months, 6 months, 1 year and 2 years. No patients were lost to follow up. The patellar tilt and shift were measured at 6 weeks, 3months, 6months, 1year and 2 years via skyline view radiography. The knee society scores, Oxford knee score, knee injury and osteoarthritis outcome score, forgotten joint score and Kujala scale also were recorede at 6 weeks, 3months, 6months, 1 year and 2 years.

Study Overview

• Status: Completed
• Conditions: Anterior Knee Pain
• Intervention / Treatment: Procedure: removing osteophyte at patellofemoral joint

Detailed Description

Removing and non-removing osteophyte at patellofemoral joint is controversial topic. The osteophyte may help to reduce load and improve stability of patellofemoral joint. Therefore, the purpose of this study is to compared anterior knee pain between removing and non-removing osteophyte at patellofemoral joint following medial mobile bearing unicompartmental knee arthroplasty

• Study Type: Observational
• Enrollment (Actual): 90

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 43 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

isolated medial osteoarthritis of the knee

Description

Inclusion Criteria:

• age > 42 years old
• range of motion > 90 degrees
• flexion contracture< 15 degrees
• normal function of anterior cruciate ligament

Exclusion Criteria:

• spontaneous osteonecrosis of the knee
• inflammatory joinr arthritis
• full thickness cartilage loss at lateral compartment

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
removing patellofemoral joint osteophytes; remove osteophyte at patella, medial femoral condyle and lateral femoral condyle	Procedure: removing osteophyte at patellofemoral joint; to compare anterior knee pain between removing patellofemoral joint osteophytes and non-removing patellofemoral joint osteophytes after medial unicompartmental knee arthroplasty
non-removing patellofemoral joint osteophytes; no remove osteophyte at patella, medial femoral condyle and lateral femoral condyle

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
incidence of anterior knee pain	number of participant that had anterior knee pain	6 weeks
incidence of anterior knee pain	number of participant that had anterior knee pain	3 months
incidence of anterior knee pain	number of participant that had anterior knee pain	6 months
incidence of anterior knee pain	number of participant that had anterior knee pain	1 year
incidence of anterior knee pain	number of participant that had anterior knee pain	2 year
Visual analogue scale for anterior knee pain	pain score 0= no pain and pain score 10= maximum pain	6 weeks
Visual analogue scale for anterior knee pain	pain score 0= no pain and pain score 10= maximum pain	3 months
Visual analogue scale for anterior knee pain	pain score 0= no pain and pain score 10= maximum pain	6 months
Visual analogue scale for anterior knee pain	pain score 0= no pain and pain score 10= maximum pain	1 year
Visual analogue scale for anterior knee pain	pain score 0= no pain and pain score 10= maximum pain	2 years

Collaborators and Investigators

• Sponsor: Thammasat University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2017
• Primary Completion (Actual): May 1, 2021
• Study Completion (Actual): November 1, 2021

Study Registration Dates

• First Submitted: May 1, 2022
• First Submitted That Met QC Criteria: May 4, 2022
• First Posted (Actual): May 10, 2022

Study Record Updates

• Last Update Posted (Actual): May 10, 2022
• Last Update Submitted That Met QC Criteria: May 4, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Keywords: patellofemoral pain; mobile bearing UKA; patellofemoral osteophyte; anteromedial osteoarthritis knee
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Bone Diseases; Hyperostosis; Exostoses; Osteophyte
• Other Study ID Numbers: MTU-EC-OT-0-224/62

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No