Patient Specific Instruments Versus Standard Surgical Instruments

Study Overview
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Brief Summary
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Comparison of Glenoid Component Position Using Patient Specific Instruments Versus Standard Surgical Instruments: A Randomized Prospective Clinical Trial

Detailed Description
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This is a non blinded prospective randomized clinical trial to define the efficacy of a new technology developed at the Cleveland Clinic to improve the positioning of the glenoid component in total shoulder arthroplasty. The Cleveland Clinic research team has worked on the development and validation of this new technology for the last six years. The investigators have validated the pre-operative planning software and published the results in the peer review literature (1, 7, 8, 9). The investigators have used this software in the planning of total shoulder surgery over the last three years. The investigators have validated the accuracy and reproducibility of the patient-specific instrumentation in both cadaver shoulders and Sawbones models of the shoulder using multiple surgeons. These studies also validated our ability to precisely measure component position using 3D CT scan imaging after placement of the implants in a pre-clinical cadaver study, thereby validating our ability to accurately measure and compare component position between the groups described in this proposed clinical trial. The investigators have also proven the ability of the software and techniques to produce an accurate representation of the glenoid morphology in patients with osteoarthritis or rotator cuff deficient arthritis in 13 patients. This was an IRB approved patient safety study performed at the Cleveland Clinic. The investigators have performed extensive studies of the materials and processes for the fabrication, sterilization and packaging of the patient specific instruments. The investigators have selected materials and processes that have met all of the FDA requirements for use of these materials and processes as clinical devices in vivo. These devices (non implanted instruments) are generally classified by FDA as a Class I device not having significant clinical risk. The investigators have studied the materials and process to produce accurate instruments that meet the clinical specification for fit onto the surrogate glenoid surfaces and maintain this shape and fit after sterilization. These same patient specific instruments have been tested in pre-clinical trials (Sawbones and Cadavers), demonstrating their ability to perform the functions specified with a high level of accuracy and much better than the use of standard generic instruments.

Official Title
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Comparison of Glenoid Component Position Using Patient Specific Instruments Versus Standard Surgical Instruments: A Randomized Prospective Clinical Trial

Conditions
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Total Shoulder Arthroplasty

Intervention / Treatment
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* Procedure: Glenoid Positioning System


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients otherwise indicated for primary reverse or anatomic total shoulder replacement that are able to get a pre-operative CT scan at the Cleveland Clinic will be considered eligible for enrollment. All patients will be consented in the office as part of the pre-operative consent for surgery and all will need to randomization at the time of surgery Exclusion Criteria: Patients will be excluded if they have significant metal in the joint that results in metal artifact on the CT scan, thereby compromising the ability to visualize the glenoid on the pre-operative simulator.
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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Glenoid Positioning System<br>For the patients randomized to the GPS group, the surgeon will be given the GPS patient specific instrumentation and a model of the glenoid surface showing the exact placement and fit of the GPS alignment instruments. | Procedure: Glenoid Positioning System<br>* Design and fabrication of patient specific instrument for placement of a guide pin to be used to aid in bone preparation for placement of a metaglene and its fixation screws or anatomic glenoid component<br>|
| No Intervention: Standard Group<br>Each surgeon will use their standard methods of pre-operative planning using the pre-operative x-rays and CT scan. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparing Glenoid Component Positioning to Pre Operative Planning | Final implant position will be determined by comparing the position of the glenoid component on the post-operative CT scans with the implant position planned pre-operatively on the surgical simulator. These measurements will be in degrees. | 1 month post op | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intra-operative Photographs | Intra-operative photographs will be used to qualitatively, not quantitatively, to document the surgical steps and may be useful to explain a deviation in the surgery than what would have been expected by the pre-operative simulator. No quantitative data will be collected from the photographs. | Intra-operative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Glenoid component position, patient specific instruments