Trident® X3 Polyethylene Insert Study

Study Overview
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Brief Summary
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The primary objective of the study is to demonstrate the linear wear rates of the Trident® X3 polyethylene insert are superior to a polyethylene control group wear rate at 5 years postoperative. This measurement will be evaluated by comparing digitized images of serial radiographs obtained over a follow-up period of 5-years.

Detailed Description
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The study is a prospective, multi-center, historical-controlled clinical evaluation of the Trident® X3 Polyethylene insert. The device is commercially available in the United States where the study is being conducted. The study device, the Stryker Orthopaedics Trident® X3 polyethylene insert, is used for the replacement of the bearing surface of the acetabulum to relieve pain, instability, and the restriction of motion due to degenerative bone disease, including osteoarthritis, rheumatoid arthritis, trauma, or failure of other devices. The control device, the Stryker Orthopaedics N2VAC polyethylene insert, is also used for the replacement of the bearing surface of the acetabulum to relieve pain, instability, and the restriction of motion due to degenerative bone disease, including osteoarthritis, rheumatoid arthritis, trauma, or failure of other devices.

Official Title
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An Open-label, Prospective, Post-market, Historically Controlled, Multi-center Clinical Evaluation of the Trident® X3 Polyethylene Acetabular Inserts.

Conditions
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Arthroplasty, Replacement, Hip

Intervention / Treatment
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* Device: Trident® X3 Polyethylene Insert


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The patient has signed an IRB-approved, study specific Patient Informed Consent Form. The patient is a candidate for a primary total hip replacement with cementless acetabular and femoral components. The patient has a primary diagnosis of Non-Inflammatory Degenerative Joint Disease (NIDJD). Patient must have diagnosis of osteoarthritis (OA), traumatic arthritis (TA), avascular necrosis (AVN), slipped capital epiphysis, pelvic fracture, femoral fracture, failed fracture fixation, or diastrophic variant. The patient is a male or non-pregnant female patient ages 21 to 75. The patient is willing and able to comply with postoperative scheduled clinical and radiographic evaluations and rehabilitation. Exclusion Criteria: The patient has an active infection with the affected hip joint. The patient requires revision surgery of a previously implanted total hip arthroplasty or hip fusion to the affected joint. The patient has a BMI >45. The patient has a neuromuscular or neurosensory deficiency, which limits ability to evaluate the safety and efficacy of the device. The patient has diagnosed systemic disease (i.e. Paget's disease, renal osteodystrophy). The patient is immunologically suppressed or receiving chronic steroids in excess of 5mg per day. The patient has a recent history of substance dependency that may result in deviations from the evaluation schedule. The patient is a prisoner.

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 75 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Trident® X3 Polyethylene Insert<br>Participants who received the Trident® X3 Polyethylene Insert. | Device: Trident® X3 Polyethylene Insert<br>* Trident® X3 Polyethylene Insert<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Linear Wear Rate at 5 Years | Linear wear rates are defined as the annual rate of removal of the polyethylene from the polyethylene insert determined by comparing digitized images of serial radiographs obtained over the follow-up period of 5 years | 5 years | 
| Rate of Incidence of Revision of Component for Any Reason | Revision of any component is defined as surgical removal and replacement of the femoral component, acetabular shell, acetabular insert and/or femoral head. | 5 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Linear Wear Rate of the Trident X3 Polyethylene Insert | Linear wear rates are defined as the annual rate of removal of the polyethylene from the polyethylene insert determined by comparing digitized images of serial radiographs obtained over the follow-up period. NOTE: 2 year linear and volumetric wear was not calculated for the following reason: To determine polyethylene wear, the total femoral head penetration is first calculated from the radiographs.The femoral head penetration has two components namely wear and creep (or bedding-in). It is not possible to separate the total penetration in to two components. The creep of the polyethylene starts from the date of surgery and continues up to 12-24 months. Therefore, the head penetration value at 2-years is dominated by Creep rather than wear. | 2, 3 and 4 year films collected; 3 and 4 year wear assessed | 
| Volumetric Wear Rate of the Trident X3 Polyethylene Insert | Volumetric wear rate is calculated using a formula based on the cylindrical wear pattern perpendicular to the face of the cup and the mean linear wear rate. NOTE: 2 year linear and volumetric wear was not calculated for the following reason: To determine polyethylene wear, the total femoral head penetration is first calculated from the radiographs.The femoral head penetration has two components namely wear and creep (or bedding-in). It is not possible to separate the total penetration in to two components. The creep of the polyethylene starts from the date of surgery and continues up to 12-24 months. Therefore, the head penetration value at 2-years is dominated by Creep rather than wear. | 2, 3, 4 and 5 year films collected; 3, 4 and 5 year wear assessed | 
| Radiographic Stability | Radiographic stability is defined as having all of the following: no radiographic indication of progressive radiolucent lines greater than or equal to 2 mm around the entire acetabular cup, no radiographic indication of acetabular cup migration of greater than or equal to 3 mm, no radiographic indication of progressive radiolucent lines greater than or equal to 2 mm around the entire femoral component, and no radiographic indication of progressive subsidence of the femoral component of greater than or equal to 5 mm. Radiographs are evaluated at 1,2,3,4 and 5 years. | 1,2,3,4 and 5 years | 
| Mean Harris Hip Score (HHS) to Assess Change | The change in HHS is reported by comparing the mean preoperative, 1, 3 and 5 year postoperative scores that assess pain, function, joint deformity and range of motion. Scores can range from 0 to 100 with 0 being the worst and 100 being the best score. A score of 80-100 is considered good-excellent and a score less than or equal to 79 is considered fair-poor. 90 - 100 = excellent 80 - 89 = good 70 - 79 = fair 0 - 69 = poor | pre-operative, 1,3 and 5 years | 
| Mean Harris Hip Score (HHS) Pain Score to Assess Change | The change in HHS Pain is reported by comparing the mean preoperative, 1, 3 and 5 year postoperative pain scores. Scores can range from 0 to 44, with 0 indicating totally disabling pain and 44 indicating no pain or pain that is ignored. None or ignores it = 44 points Slight, occasional, no compromise in activities = 40 points Mild pain, no effect on average activities, rarely moderate pain with unusual activity;may take aspirin = 30 points Moderate pain, tolerable, but makes concessions to pain. Some limitation of ordinary activity or work. May require occasional pain medication stronger than aspirin = 20 points Marked pain, serious limitation of activites = 10 points Totally disabled, crippled, pain in bed, bedridden = 0 points | pre-operative, 1,3, and 5 years | 
| Mean Harris Hip Score (HHS) Range of Motion (ROM) Score to Assess Change | The change in HHS ROM is reported by comparing the mean preoperative, 1, 3 and 5 year postoperative scores. Scores can range from 0 (worst) to 5 (best). The degrees of motion are measured for hip flexion, abduction, adduction, external rotation and internal rotation. The measured values are added to determine a combined value that is associated with a score from 0 to 5. 211-300 degrees = 5 points 161 to 210 degrees = 4 points 101 to 160 degrees = 3 points 61 to 100 degrees = 2 points 31 to 60 degrees = 1 points 0 to 30 degrees = 0 points | pre-operative, 1,3 and 5 years | 
| Mean SF-12 Health Survey Score to Assess Change | Change in the SF-12 score is reported by comparing the mean preoperative, 1,3 and 5 year postoperative scores.The SF-12 Health Survey is a 12-item patient completed questionnaire to measure general health and well-being. It includes a physical and mental status component score; each ranging from 0-100. Low values represent a poor health state and high values represent a good health state. | pre-operative, 1,3 and 5 years | 
| Mean Lower Extremity Activity Scale (LEAS) Score to Assess Change | Change in the LEAS is reported by comparing the mean preoperative, 1,3 and 5 year scores. The LEAS is completed by the participant to assess activity level. Activity levels are ordered in terms of intensity from 1 to 18, with 18 indicating the highest activity level. | pre-operative, 1,3 and 5 years | 
| Implant Survivorship | Implant survivorship is determined using the Kaplan-Meier method. | 10 years |