(86 days)
Femoral and/or proximal tibial replacement due to
- Trauma .
- Failed previous prosthesis .
- Tumor resection .
The following configurations of MRS Cemented Stems will be available:
Standard Cemented Stems:
- Straight stem with 40mm porous coated body distal diameters/seat diameters are ◆ 11mm/24mm, 13mm/28mm, 15mm/32mm, 17mm/36mm - 127mm in length
- Straight stem without body distal diameters/seat diameters are 11mm/24mm, . 13mm/28mm, 15mm/32mm, 17mm/36mm - 127mm in length
- Curved stem with 40mm porous coated body distal diameters/seat diameters are . 11mm/24mm, 13mm/28mm, 15mm/32mm, 17mm/36mm - 127mm in length
- Curved stem without body distal diameters/seat diameters are 11mm/24mm, . 13mm/28mm, 15mm/32mm, 17mm/36mm - 127mm in length
- Curved stem with 40mm porous coated body distal diameters/seat diameters are . 11mm/24mm, 13mm/28mm, 15mm/32mm, 17mm/36mm - 203mm in length
- Curved stem without body distal diameters/seat diameters are 11mm/24mm, . 13mm/28mm, 15mm/32mm, 17mm/36mm - 203mm in length
Standard cemented femoral stems will be used in the proximal femur, distal femur, and proximal tibia. These stems may be used with the standard and small distal femoral component, and standard and small proximal tibial component of the MRS and/or GMRS™ systems.
Small Cemented Stems: - Straight stem with 40mm porous coated body distal diameters/seat diameters are . 8mm/24mm, 9mm/24mm, 10mm/24mm - 102mm in length
- Straight stem without body distal diameters/seat diameters are 8mm/24mm, . 9mm/24mm, 10mm/24mm - 102mm in length
- Curved stem with 40mm porous coated body distal diameters/seat diameters are . 8mm/24mm, 9mm/24mm, 10mm/24mm - 102mm in length
- Curved stem without body distal diameters/seat diameters are 8mm/24mm, . 9mm/24mm, 10mm/24mm - 102mm in length
These stems may be used with the small Distal Femoral component, and small proximal tibial component of the MRS and/or GMRSTM systems.
All of the stems utilize a Morse taper to connect to the proximal femoral/distal femoral or proximal tibial components. The taper angle is 2 degrees 52 minutes. At the distal end of the larger stems is a recessed hole to allow the optional use of a cement centralizer.
The provided text does not contain a study that proves the device meets specific acceptance criteria in the manner described in the request (e.g., performance metrics, sample sizes, ground truth establishment, or expert involvement).
Instead, this document is a 510(k) Premarket Notification for a medical device (Modular Replacement System Cemented Stems). It describes the device, its intended use, indications for use, contraindications, and design changes. The primary goal of a 510(k) submission is to demonstrate substantial equivalence to a predicate device, not necessarily to set and meet new performance acceptance criteria through a specific detailed study as would be done for a novel AI/software medical device.
The document states:
- "An engineering analysis was presented to support a claim of substantial equivalence to the predicate devices." (Page 4)
- The FDA letter confirms that the device is "substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices..." (Page 4)
Therefore, comprehensive information regarding acceptance criteria and a study proving those criteria are met, particularly with details like sample sizes, data provenance, expert ground truth, and statistical performance metrics, is not available in the provided text.
Based on the information available, here's what can be extracted:
1. A table of acceptance criteria and the reported device performance
| Acceptance Criteria (Implicit) | Reported Device Performance (Implicit) |
|---|---|
| Substantial Equivalence to predicate devices (existing MRS Proximal Femoral Stems, Distal Femoral Stems, and Proximal Tibial Stems). | Demonstrated substantial equivalence through an engineering analysis. |
Note: The document focuses on demonstrating substantial equivalence through engineering analysis and comparison to existing predicate devices rather than establishing and meeting quantitative performance metrics for a novel technology.
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Not applicable as this was an engineering analysis for substantial equivalence, not a clinical trial or performance study with a test set of patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
- Not applicable. Ground truth as typically understood for diagnostic or AI performance studies is not relevant to this 510(k) submission for substantial equivalence based on engineering analysis.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable.
5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
- Not applicable. This device is a physical orthopedic implant, not an AI-based diagnostic tool.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is a physical device, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Not applicable in the context of a typical performance study. The "ground truth" for substantial equivalence here is the performance and safety profile of the predicate devices.
8. The sample size for the training set
- Not applicable. This involves an engineering analysis of a physical device, not a machine learning model.
9. How the ground truth for the training set was established
- Not applicable.
§ 888.3510 Knee joint femorotibial metal/polymer constrained cemented prosthesis.
(a)
Identification. A knee joint femorotibial metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits translation or rotation in one or more planes and has components that are linked together or affined. This generic type of device includes prostheses composed of a ball-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a ball at the head of a column rising from the stemmed tibial component. The ball, the column, the tibial plateau, and the stem for fixation of the tibial component are made of an alloy, such as cobalt-chromium-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the femoral component's flat outer surface. The flat outer surface of the tibial component abuts both a reciprocal flat surface within the cavity of the femoral component and flanges on the femoral component designed to prevent distal displacement. The stem of the femoral component is made of an alloy, such as cobalt-chromium-molybdenum, but the socket of the component is made of ultra-high molecular weight polyethylene. The femoral component has metallic runners which align with the ultra-high molecular weight polyethylene tracks that press-fit into the metallic tibial component. The generic class also includes devices whose upper and lower components are linked with a solid bolt passing through a journal bearing of greater radius, permitting some rotation in the transverse plane, a minimal arc of abduction/adduction. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.