(275 days)
Disposable cement spacer molds are indicated for use to mold a temporary hemi-shoulder replacement for skeletally mature patients undergoing a two-stage revision procedure due to a septic process. The temporary prosthesis is molded using Cobalt™ HV with Gentamicin Bone Cement and inserted into the humeral medullary canal and glenoidal cavity following removal of the existing total shoulder replacement implants and debridement. The device is intended for use in conjunction with systemic antimicrobial antibiotic therapy (standard treatment approach to an infection).
The hemi-shoulder prosthesis made from the StageOne™ disposable cement molds is not intended for use more than 180 days, at which time it must be explanted and permanent devices implanted or another appropriate treatment performed (e.g. resection arthroplasty, fusion, etc.)
Due to the inherent mechanical limitations of the hemi-shoulder prosthesis material (Cobalt™ HV with Gentamicin Bone Cement), the temporary hemi-shoulder prosthesis is only indicated for patients who will consistently follow activity limitations throughout the implant period.
The single-use cement spacer molds are sterile disposables made of medical grade silicone. They are designed to be filled with Cobalt™ HV with Gentamicin bone cement by injecting with a dispenser/gun into the mold. After the cement cures, the hemi-shoulder prosthesis is to be removed from the mold and placed into the joint space. The hemi-shoulder prosthesis remains in place (180 days or less) until the second stage of the two-stage procedure is performed to implant a conventional shoulder joint prosthesis.
Here's a summary of the acceptance criteria and the study that proves the device meets them, based on the provided text:
Device Description:
The StageOne™ Disposable Cement Spacer Molds for Temporary Hemi-Shoulder Prosthesis are sterile, single-use molds made of medical-grade silicone. They are designed to be filled with Cobalt™ HV with Gentamicin bone cement to create a temporary hemi-shoulder prosthesis. This temporary prosthesis is used for skeletally mature patients undergoing a two-stage revision procedure due to a septic process, and it remains in place for 180 days or less.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Fatigue Strength | Substantially equivalent to the predicate Tecres InterSpace® Shoulder (K112983). |
| Static Strength | Substantially equivalent to the predicate Tecres InterSpace® Shoulder (K112983). |
| Gentamicin Elution | The percentage of total gentamicin eluted from the spacer made from a StageOne™ shoulder spacer mold and Cobalt™ HV with Gentamicin bone cement was substantially equivalent to the percentage of gentamicin eluted from the predicate Tecres InterSpace® Shoulder (K112983). |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the specific sample sizes used for the comparative mechanical (fatigue and static strength) or antibiotic elution testing.
The provenance of the data is non-clinical test data. The country of origin of the data is not specified, but it would have been generated in a laboratory setting by Biomet Manufacturing Corp. or a contracted testing facility.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
Not applicable. This device's performance was evaluated through non-clinical laboratory testing (mechanical and elution studies), not by expert assessment of clinical data or images.
4. Adjudication Method for the Test Set
Not applicable. As noted above, the evaluation involved non-clinical laboratory testing, not human expert adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No, an MRMC comparative effectiveness study was not done. The submission explicitly states: "No clinical data submitted." and "No clinical data was necessary for a determination of substantial equivalence."
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Not applicable. This is a medical device (a mold for a temporary prosthesis), not an algorithm or AI system.
7. The Type of Ground Truth Used
The "ground truth" for the non-clinical tests was established by comparison to a legally marketed predicate device (Tecres InterSpace® Shoulder, K112983) and adherence to established engineering principles for mechanical testing and analytical chemistry for elution testing. The acceptance criteria were based on achieving "substantial equivalence" to this predicate.
8. The Sample Size for the Training Set
Not applicable. This device is not an AI/ML product, so there is no training set in the conventional sense. The design and validation of the device relied on engineering principles and comparative non-clinical testing.
9. How the Ground Truth for the Training Set Was Established
Not applicable. As this is not an AI/ML product, there is no training set or ground truth establishment method for such a set.
§ 888.3027 Polymethylmethacrylate (PMMA) bone cement.
(a)
Identification. Polymethylmethacrylate (PMMA) bone cement is a device intended to be implanted that is made from methylmethacrylate, polymethylmethacrylate, esters of methacrylic acid, or copolymers containing polymethylmethacrylate and polystyrene. The device is intended for use in arthroplastic procedures of the hip, knee, and other joints for the fixation of polymer or metallic prosthetic implants to living bone.(b)
Classification. Class II (special controls). The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance Document: Polymethylmethacrylate (PMMA) Bone Cement.”