Clinical Outcome and OR Resource Use of Total Knee Arthroplasty Using Patient-Specific or Conventional Instrumentation

Study Overview
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Brief Summary
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Compare OR resource use and clinical Outcome after Total Knee Arthroplasty using Patient-specific or conventional Instrumentation.

Detailed Description
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The aim of this study was to compare OR resource use and clinical Outcome after Total Knee Arthroplasty (TKA) using Patient-specific (PSI) or conventional Instrumentation. For this purpose, economic variables of the surgery (number of instrument trays, setup and cut-sew-time), radiological alignment and patient reported outcomes (VAS Pain Scale, Oxford Knee Score, EQ-5D) were assessed. Cost per QALY (quality-adjusted life year) was assessed using the German DRG reimbursement and the EQ-5D. A total of 139 TKA with PSI or conventional instrumentation were included in three Centers and were assessed before surgery, as well as 6 weeks, 6 and 12 months postoperatively.

Official Title
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Evaluation of Zimmer® Patient Specific Instrumentation vs. Conventional Instrumentation in Total Knee Arthroplasty Procedures: Clinical and Economic Outcomes

Conditions
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Gonarthrosis

Intervention / Treatment
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* Procedure: PSI
* Procedure: Conventional


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Painful, disabled knee joint resulting from osteoarthritis requiring primary TKA Informed Consent: Patient has signed a Patient Informed Consent. Able and willing to undergo a preoperative MRI scan (for PSI cases) and full-leg, standing radiographs (all cases) Able and willing to follow instructions and complete follow-up Patient receiving Zimmer NexGen Solutions CR-Flex (including Gender Solutions) Exclusion Criteria: Patient is skeletally immature Active Infection (including septic knee, distant infection, or osteomyelitis) Severe hip arthrosis Neurological disorders (including, but not limited to Parkinson's disease) Prior unicompartmental knee arthroplasty, TKA, knee fusion or patellectomy Hip or knee ankylosis Either rheumatoid or post-traumatic knee arthritis Scheduled for simultaneous bilateral TKA Indications of intra- and/or extra-articular deformations that would inhibit the use of PSI guides Any metal within 150 mm of the joint line for the operative-side knee Knee deformities greater than 15 degrees of fixed varus, valgus, or flexion contracture on initial physical examination An existing condition that would, in the opinion of the investigator, compromise participation or follow-up in this study A female who is pregnant or lactating Current involvement in any personal injury litigation, medical-legal or worker's compensation claims Arterial disease or stents that would exclude the use of a tourniquet

Ages Eligible for Study
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Minimum Age: 18 Years

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: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients were operated consecutively with conventional and patient-specific Instrumentation.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PSI<br>Patients received TKA using patient-specific Instrumentation. | Procedure: PSI<br>* Implantation of a Total Knee Arthroplasty patient-specific instrumentation using Zimmer® NexGen Solutions (Zimmer Biomet, Warsaw, IN).<br>|
| Active Comparator: Conventional<br>Patients received TKA conventional Instrumentation. | Procedure: Conventional<br>* Implantation of a Total Knee Arthroplasty with conventional using Zimmer® NexGen Solutions (Zimmer Biomet, Warsaw, IN).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| OR time | Operating Room (OR) time: incision to Close in minutes | during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| OR resource use: number of instrument trays | OR Efficiency measured by number of instrument trays used | during surgery | 
| OR Setup Time | Operating Room (OR) Setup Time in minutes | during surgery | 
| Oxford Knee Score | clinical outcome measured by the Oxford Knee Scoring System. The Oxford Knee Score is aggregated to a single score where 0 is the worst and 48 is the best Outcome. | 1 year after surgery | 
| visual analog scale (VAS) | patient-reported pain scores as measured by the visual analog scale (VAS), ranging from 0 (worst) to 10 (best). | 1 year after surgery | 
| device alignment | device alignment as determined using radiographs (A/P long-standing and lateral films) | 1 year after surgery | 
| EQ-5D-3L | patients' health-related Quality of life is measured by the EQ-5D-3L, which aggregates to a single index where 0 is the worst and 1 is the best outcome | 1 year after surgery |