A Retrospective Study of the Navio Robotic-assisted Surgical System

Study Overview
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Brief Summary
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A retrospective, multi-center, cohort study with prospective follow-up and comparison to historical control

Detailed Description
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Subjects who had previously received the Navio robotic-assisted surgical system for unilateral knee replacement (UKR) were assessed to determine the 2-year safety and effectiveness of the Navio system.

Official Title
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A Retrospective Study of the Navio™ Robotic-assisted Surgical System

Conditions
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Surgical Robotics, Knee Replacement

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female subjects ≥ 18 years old (at the time of surgery) who have undergone Navio System-assisted UKR at least 2 years prior to enrollment. This includes UKR procedures with all Unicondylar Knee cemented implant designs. Subject had a primary diagnosis of unicompartmental, non-inflammatory degenerative joint disease including osteoarthritis, traumatic arthritis, or avascular necrosis, required correction of functional deformity, or required treatment of fractures that were unmanageable using other techniques. Exclusion Criteria: Subject received the Navio System-assisted UKR on the index joint as a revision for a previously failed UKR. Subject, in the opinion of the Investigator, had advanced osteoarthritis or joint disease at the time of surgery and was better suited for Total Knee Arthroplasty (TKA). Subject, in the opinion of the Investigator, had a neuromuscular disorder that prohibited control of the index joint. Subject, in the opinion of the Investigator, was morbidly obese. Subject, in the opinion of the Investigator, was contraindicated for UKR. Subject (prospective subjects only), in the opinion of the Investigator, has an emotional or neurological condition including mental illness, mental retardation, drug or alcohol abuse. Subject (prospective subjects only) is a prisoner.

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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluate the Navio™ System for Revisions at 2+ Years Post-surgical Implantation Survivorship | Analysis of the absence of device revision (overall survivorship) outcomes assessed from Baseline through 120 weeks post-surgical implantation. | Preoperative (Baseline) and 24, 48, 72, 96, and 120 weeks postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of Efficacy Based on Knee Society Score (KSS) Assessments | Analysis of KSS from preoperatively (Baseline) up to 36 months postoperatively in 6-months increments to evaluate objective observation, patient satisfaction, and function. Objective knee indicators: Range 0-100 points; Patient Satisfaction: Range 0-40 points; and Functional Activities: Range 0-100 points. Higher scores indicated a better outcome. | Preoperative (Baseline) and 6, 12, 18, 24, 30, and 36 months postoperatively | 
| Evaluation of Efficacy Based on Veterans RAND 12 (VR-12) Assessments | Analysis of VR-12 scores preoperatively (Baseline) through 36 months postoperatively in 6 months increments. These scores encompass the individual domains of physical component score (PCS), mental component score (MCS) as well as the sub-domain scores within the PCS (physical functioning, role physical, bodily pain, and general health) and those within the MCS (vitality, social functioning, role emotional, and mental health). Domain Scores: Physical Component Score (PCS): Range 1 to 20 Mental Component Score (MCS): Range 1 to 25 Sub-domain Scores: Physical Functioning: Range 1 to 6 Role Physical: Range 1 to 4 Bodily Pain: Range 1 to 6 General Health: Range 1 to 6 Vitality: Range 1 to 6 Social Functioning: Range 1 to 6 Role Emotional: Range 1 to 4 Mental Health: Range 1 to 10 Transformation of raw scale scores (range 0-100) = {(actual raw score - lowest possible raw score)/possible raw score range} x100 A higher score indicates a better outcome. | Preoperative (Baseline) and 6, 12, 18, 24, 30, and 36 months postoperatively | 
| Preoperative Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (anterior-posterior [AP] and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | Preoperative (Baseline) | 
| Postoperative 6-Month Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (AP and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | 6 months postoperatively | 
| Postoperative 12-Month Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (AP and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | 12 months postoperatively | 
| Postoperative 18-Month Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (AP and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | 18 months postoperatively | 
| Postoperative 24-Month Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (AP and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | 24 months postoperatively | 
| Postoperative 30-Month Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (AP and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | 30 months postoperatively | 
| Postoperative 36-Month Evaluation of Efficacy Based on Radiographic Findings | Changes in radiographic findings (AP and lateral x-rays) from Baseline to 3 years postoperatively were collected for the SAF population. | 36 months postoperatively |