Comparison Between the Onlay and Inlay Techniques for Patellar Resurfacing in Posterior Cruciate Ligament-Substituting Total Knee Arthroplasty

Study Overview
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Brief Summary
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The purpose of this study is to compare clinical outcome in posterior cruciate ligament-substituting total knee arthroplasty with onlay patellar resurfacing technique and inlay patellar resurfacing technique

Official Title
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Comparison Between the Onlay and Inlay Techniques for Patellar Resurfacing in Posterior Cruciate Ligament-Substituting Total Knee Arthroplasty: A Prospective, Randomized Controlled Trial

Conditions
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Onlay Patellar Resurfacing Technique, Inlay Patellar Resurfacing Technique, Patellar Resurfacing

Intervention / Treatment
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* Procedure: Total knee with onlay patellar resurfacing technique
* Procedure: Total knee with inlay patellar resurfacing technique


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Primary osteoarthritis of knee who were scheduled for a primary total knee arthroplasty Exclusion Criteria: Valgus deformity History of inflammatory arthroplathy Previous fracture or open surgery on the same knee History of patellar instability
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Onlay patellar resurfacing technique<br> | Procedure: Total knee with onlay patellar resurfacing technique<br>* The patellar resurfacing technique that the patellar implant is embedded on the patellar bone.The patellar implant is placed on top of a flat tibial osteotomy or cut-surfaced bone<br>|
| Experimental: Inlay patellar resurfacing technique<br> | Procedure: Total knee with inlay patellar resurfacing technique<br>* The patellar resurfacing technique that the patellar implant is embedded in the patellar bone.The patellar implant is surrounded by a rim of cortical bone and supported by hardened, sclerotic bone<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of post-operative anterior knee pain | Visual Analog Scale for anterior knee pain (minimum 0, maximum 10) Do higher values represent a worse outcome | Change from baseline Visual Analog Scale for anterior knee pain at 3 months, 6 months, and 12 months after surgery | 
| range of motion of knee | Knee Society and Knee Society function score (minimum 0, maximum 200) | Change from baseline Knee Society and Knee Society function score at 3 months, 6 months, and 12 months after surgery | 
| Knee Society and Knee Society function score | Knee Society and Knee Society function score (minimum 0, maximum 200) | Change from baseline Knee Society and Knee Society function score at 3 months, 6 months, and 12 months after surgery | 
| New patellar score | New patellar score (minimum 0, maximum 30) | Change from baseline new patellar score at 3 months, 6 months, and 12 months after surgery | 
| Oxford knee score | Oxford knee score (minimum 0, maximum 48) | Change from baseline Oxford knee score 3 months, 6 months, and 12 months after surgery | 
| Prevalence of anterior knee pain ,AKP | Prevalence of anterior knee pain ,AKP (minimum 0, maximum 10) | Change from baseline Prevalence of anterior knee pain ,AKP 3 months, 6 months, and 12 months after surgery | 
| Prevalence of patellar crepitus complication | Prevalence of patellar crepitus complication (present, absent) | Change from baseline patellar crepitus complication 3 months, 6 months, and 12 months after surgery |