(24 days)
Joint replacement is indicated for patients suffering from disability due to:
- · degenerative, post-traumatic or rheumatoid arthritis;
- · avascular necrosis of the femoral condyle;
- · post-traumatic loss of joint configuration, particularly when there is patellofemoral erosion, dysfunction or prior patellectomy;
- · moderate valgus, varus or flexion deformities;
- · treatment of fractures that are unmanageable using other techniques.
This device may also be indicated in the salvage of previously failed surgical attempts. All devices are intended for cemented applications except for the 3DKNEE™ Porous Coated Femur, EMPOWR 3DKNEE™ POROUS Femur, 3DKNEE™ Porous Coated Tibia, and EMPOWR POROUS Tibia which are intended for cementless applications.
While knee replacements are not intended to withstand activity levels and loads of normal healthy bone, they are a means of restoring mobility and reducing pain for many patients.
The EMPOWR Stem Extender, 50mm implant is a modular accessory of the EMPOWR Revision Knee (K213793). When coupled with the EMPOWR Revision Knee, the Stem Extender is intended to be fixed to the bone by cement. The extender is connected to the mating implant, Revision Femur, by 7/16-20 UNF-2A male threaded connection on the implant, and 7/16-20 UNF-2B female threaded connection on the other side that is used to "extend" the length of cemented stem accessories (K173723) in an identical way as the EMPOWR Stem Extender, 25mm (K213793).
The Stem Extender is also compatible with the EMPOWR Universal Tibial Baseplate (K173723) and will be offered for use as an accessory with the baseplate.
The EMPOWR Stem 50mm Extender comes in a single diameter of 15mm and is offered a length of 50mm (Refer to Figure 1). The EMPOWR Stem Extender, 50mm is made of wrought CoCr alloy per ASTM F1537, which is identical to the material used in the 25mm extender included in the EMPOWR Revision Knee (K213793).
The provided text is a 510(k) summary for the EMPOWR™ Stem Extender, 50mm, which is a medical device. This type of submission is for clearance of a device that is substantially equivalent to a legally marketed predicate device. The document states that no clinical studies or animal studies were submitted to demonstrate the device meets acceptance criteria. Instead, substantial equivalence is claimed based on similar materials, manufacturing, sterilization processes, and performance testing against a recommended consensus standard.
Therefore, the requested information regarding acceptance criteria, study details, sample sizes, expert involvement, adjudication methods, MRMC studies, standalone performance, and ground truth for the specific device performance study cannot be extracted from this document, as such a study was not presented.
However, I can extract information about the performance testing conducted to demonstrate substantial equivalence, which serves a similar role to proving a device meets acceptance criteria in a 510(k) context.
Here's what can be extracted based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (from standard) | Reported Device Performance (from testing) |
|---|---|
| Mechanical properties as per ASTM F2083-21 (Standard Specification for Knee Replacement Prosthesis) | Demonstrated to be substantially equivalent to the predicate device. |
Note: The document states "An evaluation was performed against the recommended consensus standards for knee implants per the product codes assigned to the subject device. Of those standards, it was determined for this line extension that these additional components should be evaluated against ASTM F2083-21 (Standard Specification for Knee Replacement Prosthesis)." This implies the acceptance criteria are the specifications within ASTM F2083-21, and the reported performance is that the device met these specifications, leading to a conclusion of substantial equivalence.
2. Sample size used for the test set and the data provenance
- Sample size for the test set: Not specified in the provided text.
- Data provenance: Not explicitly stated, but assumed to be laboratory testing conducted by the manufacturer, Encore Medical, L.P.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable, as this was mechanical performance testing against a standard, not a clinical study requiring expert consensus for ground truth.
4. Adjudication method for the test set
- Not applicable, as this was mechanical performance testing.
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 not an AI diagnostic or imaging device, and no clinical studies were performed.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Not applicable. This device is not an algorithm or AI.
7. The type of ground truth used
- For mechanical performance: The technical specifications and requirements outlined in the ASTM F2083-21 standard.
8. The sample size for the training set
- Not applicable. No clinical or AI-related training was mentioned.
9. How the ground truth for the training set was established
- Not applicable. No clinical or AI-related training was mentioned.
§ 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.