K Number
K223441
Manufacturer
Date Cleared
2023-03-23

(129 days)

Product Code
Regulation Number
888.3390
Panel
OR
Reference & Predicate Devices
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The SpaceFlex Acetabular Cup consists of disposable cement spacer molds indicated for use to mold a temporary Acetabular cup replacement for skeletally mature patients undergoing a two-stage procedure due to a septic process.

The temporary prosthesis is molded using low viscosity antibiotic polymethylmethacrylate bone cement (G3A 40 bone cement) and positioned into the acetabular cavity following removal of the existing acetabular and femoral components and radical debridement.

The molded acetabular cup is intended for use in conjunction with systemic antimicrobial antibiotic therapy (standard treatment approach to an infection). The molded temporary Acetabular cup prosthesis is indicated for an implantation period of 180 days or less. Because of inherent mechanical limitations of the device material (Bone Cement), the molded temporary prosthesis is only indicated for patients who will consistently use traditional mobility assist devices (e.g., crutches, walkers) throughout the implant period.

Device Description

The SpaceFlex Acetabular Cup consists of disposable cement spacer molds. The molds are comprised of a lower mold, an upper mold, an injector, and tightening clips. The lower mold has a fixed diameter and couples with one of three upper molds. The upper mold has five channels for air flow and four holes for clips. The injector connects to the upper mold for bone cement injection. Tightening clips secure the upper and lower molds. The system is filled with low viscosity antibiotic polymethylmethacrylate bone cement. After curing, the temporary spacer is removed and placed into the joint space for up to 180 days.

AI/ML Overview

The SpaceFlex Acetabular Cup is a device that consists of disposable cement spacer molds used to create a temporary acetabular cup replacement for patients undergoing a two-stage procedure due to a septic process. The temporary prosthesis is molded using low viscosity antibiotic polymethylmethacrylate bone cement (G3A 40 bone cement).

Here's an analysis of its acceptance criteria and the study proving its performance:

1. Table of Acceptance Criteria and Reported Device Performance:

TestAcceptance CriteriaReported Device Performance
Rupture Test400 NSuccessfully exceeded 400 N (evaluated the compression strength of the bone cement acetabular cup under a ramp of load up to failure).
Fatigue Test (per ASTM 3090-20:2020)500,000 cycles without a breakCompliant with the acceptance criteria of 500,000 cycles without a break.
Wear Test (per ISO 14242-1-2014)500,000 cycles without a breakCompliant with the acceptance criteria of 500,000 cycles without a break.
Gentamicin Elution TestElution behavior profiles comparable to G3A bone cement cylinderThe elution behavior profiles of the tested specimens (different sizes of SpaceFlex Acetabular Cup) were comparable with the elution behavior profile of the G3A bone cement cylinder.
Molding Temperature Analysis TestDid not exceed the maximum tolerable temperature of the mold material (120°C) during polymerizationThe tested sample did not reach or exceed the maximum temperature limit of 120°C during the cement polymerization process.
Biocompatibility (FTIR-ATR Analysis)No evidence of chemical modifications on the surface of the cement after curing in contact with the moldFTIR-ATR analysis on polymer matrix (not-aged and after-accelerated aging) showed no evidence of chemical modifications on the surface of the cement after curing in contact with the mold. This was based on data from a previous submission (K190216, SpaceFlex Knee) due to the use of the same mold materials and manufacturing processes.

2. Sample Size Used for the Test Set and Data Provenance:

The document describes bench testing for performance evaluation. Specific sample sizes for each test are not explicitly detailed in the provided text. However, for the Gentamicin Elution Test, it mentions "different sizes (52 and 60 mm)" were tested. The data provenance is from bench testing conducted by G21, S.r.l. and is prospective in nature, as it involves testing the manufactured device components. This is not clinical data, but rather engineering and material property testing.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:

This information is not applicable as the described studies are bench tests (mechanical and material property assessments) rather than studies requiring expert interpretation of clinical data or images. The "ground truth" for these tests is established by industry standards (e.g., ASTM, ISO) and the device's design specifications.

4. Adjudication Method for the Test Set:

This information is not applicable for the bench tests described. Adjudication methods are typically used in studies involving human interpretation or clinical outcomes.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done:

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. The provided text describes only bench testing of the device's mechanical properties and material interactions, not a study involving human readers or clinical effectiveness compared to an alternative.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done:

This information is not applicable. The SpaceFlex Acetabular Cup is a physical medical device (molds for a temporary prosthesis), not an algorithm or AI system. Therefore, standalone algorithm performance is not relevant.

7. The Type of Ground Truth Used:

The ground truth for the performance tests is based on engineering and material science standards (e.g., ASTM 3090-20:2020, ISO 14242-1-2014) and the device's defined specifications (e.g., 400 N compression strength, 500,000 cycles for fatigue and wear, 120°C temperature limit, comparable elution profiles, no chemical modification).

8. The Sample Size for the Training Set:

This information is not applicable. As this is a physical medical device undergoing bench testing, there is no "training set" in the context of machine learning or AI.

9. How the Ground Truth for the Training Set Was Established:

This information is not applicable for the same reason as point 8.

§ 888.3390 Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis.

(a)
Identification. A hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis is a two-part device intended to be implanted to replace the head and neck of the femur. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a snap-fit acetabular component made of an alloy, such as cobalt-chromium-molybdenum, and ultra-high molecular weight polyethylene. This generic type of device may be fixed to the bone with bone cement (§ 888.3027) or implanted by impaction.(b)
Classification. Class II.