(210 days)
Limb salvage surgery is indicated for cemented procedures where radical resection and replacement of the distal femur and/or proximal tibia is required with the following conditions:
- patients suffering from severe arthropathy of the knee that does not respond to any conservative therapy or better alternative surgical treatment;
- surgical intervention for severe trauma, revision knee arthroplasties, and/or oncology indications.
- metastatic diseases (e.g., osteosarcomas, chondrosarcomas, gaint cell tumors, bone tumors)
The REPIPHYSIS™ Prosthesis is custom assembled for each patient. The REPIPHYSIS™ is implanted the same way as any other joint replacement device using non-allergic, standard materials that have been tested in biological situations. The REPIPHYSIS™ Limb Salvage Prosthesis Kit consists of the following components: Distal Hinge Femur, Tibial Base, Axial Bushing, Axial Pin. The REPIPHYSIS™ prosthesis uses an external electro-magnetic transmitter to activate the implant lengthening mechanism. The REPIPHYSIS Transmitter Unit operates by producing an electrical current in an inductor coil, which in turn generates a strong electro-magnetic field in the vicinity of the coil. When an electrically conductive material is placed within this electro-magnetic field, an electrical current is induced in the conductive material. If the proper conditions are established, this electrical current is sufficient to cause significant heating in this material. The REPIPHYSIS™ prosthesis consists of two tubes with a spring mechanism contained in the larger tube. It is maintained compressed by a polyacetal locking mechanism. One tube is connected to the stem of the implant, and the second comprises the hinge portion of the hinge prosthesis. The uninvolved side of the joint is minimally resurfaced with a press-fit stem to attempt to preserve function of the non-involved growth plate. Expansion is achieved via exposure to an external electromagnetic field around the extremity. The coil transmits an electromagnetic field around the implant in the vicinity of the v-shaped flange of the spring housing tube. This generates an electrical current within the flange of the spring housing tube and is focused on the receiving antennae within the implant itself. This antenna is heated by the electromagnetic field. The heated element softens the surrounding polyacetal locking mechanism, which allows the spring expansion. The spring expansion pushes the two tubes apart from each other, thus lengthening the overall length of the leg.
This document is a 510(k) Summary of Safety and Effectiveness for the REPIPHYSIS™ Limb Salvage System. It focuses on establishing substantial equivalence to previously cleared devices rather than providing a detailed study proving the device meets specific acceptance criteria with quantifiable performance metrics.
Therefore, many of the requested details about acceptance criteria, study design, and performance metrics are not present in this type of regulatory submission. The document primarily describes the device, its intended use, and argues for its substantial equivalence based on materials, design, and testing results without providing the specifics of those tests or their acceptance criteria in the format requested.
Here's an attempt to answer the questions based only on the provided text, indicating when the information is not available:
1. A table of acceptance criteria and the reported device performance
Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Not Explicitly Stated in Document) | Reported Device Performance (From Document) |
|---|---|
| Not explicitly stated. The document focuses on substantial equivalence to predicate devices, implying performance comparable to legally marketed devices. | The REPIPHYSIS™ Limb Salvage System's safety and effectiveness are "adequately supported by the substantial equivalence information, materials data, and testing results provided within the Premarket Notification." |
Specific, quantifiable performance metrics (e.g., probability of failure, mechanical integrity, accuracy of lengthening to within a certain tolerance, biocompatibility test results with specific acceptance limits, etc.) are NOT detailed in this summary. The summary highlights the mechanism of lengthening and implies functionality.
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: Not specified. This document refers to "testing results" and "materials data" but does not detail the sample sizes for any specific tests or studies.
- Data Provenance: The document states that the REPIPHYSIS™ Limb Salvage System was previously named the Phenix Growing Prosthesis and that "More than 100 patients have been treated with Phenix Growing Prosthesis in the last 20 years." This suggests some level of historical clinical experience, likely retrospective, originating from France ("designed in France in the early 1980s"). However, it's not explicitly stated if this patient data constitutes a "test set" for the current 510(k) submission or if it was used to establish performance against acceptance criteria.
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 specified. The document does not describe a clinical study or expert-based ground truth establishment process for a "test set" in the context of device performance evaluation.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not specified. No adjudication method is mentioned as there is no described clinical study requiring such a process for a test set.
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
No. The document describes a medical device (an implantable prosthesis) for limb salvage, not an AI-assisted diagnostic or interpretative tool. Therefore, an MRMC comparative effectiveness study involving human readers and AI assistance is not applicable and not mentioned.
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 software requiring standalone performance testing. It is a physical implantable device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- The document implies that the safety and effectiveness are supported by "substantial equivalence information, materials data, and testing results." This suggests a reliance on engineering testing, material characterization, and potentially clinical outcomes data from the predicate device (Phenix Growing Prosthesis).
- The "more than 100 patients treated with Phenix Growing Prosthesis" likely provided outcomes data to support the overall safety and effectiveness indirectly, but the specific metrics and how they constitute "ground truth" for the current submission are not detailed.
- The "Indications Statement" uses terms like "patients suffering from severe arthropathy... that does not respond to any conservative therapy or better alternative surgical treatment," and "surgical intervention for severe trauma, revision knee arthroplasties, and/or oncology indications," which imply clinical diagnosis and established medical conditions as the basis for using the device.
8. The sample size for the training set
Not applicable. This device is not an AI/ML algorithm that requires a "training set."
9. How the ground truth for the training set was established
Not applicable, as there is no "training set" for this device.
{0}------------------------------------------------
Image /page/0/Picture/0 description: The image shows the logo for Wright Medical Technology, Inc. The logo consists of a stylized "W" made up of three black triangles, followed by the company name in bold, sans-serif font. Below the company name is the address "5677 Airline Road, Arlington, TN 38002" and the phone number "901-867-9971".
K021489
Page 1 of 4
DEC (1 4 2002
510(K) SUMMARY OF SAFETY AND EFFECTIVENESS
In accordance with the Food and Drug Administration Rule to implement provisions of the Safe Medical Devices Act of 1990 and in conformance with 21 CRF 807, this information serves as a Summary of Safety and Effectiveness for the use of the REPIPHYSIS™ Limb Salvage System.
| Submitted By: | Wright Medical Technology, Inc. |
|---|---|
| Date: | May 7, 2002 |
| Contact Person: | Ehab M. EsmailManager, Regulatory Affairs |
| Proprietary Name: | REPIPHYSIS™ Limb Salvage System |
| Common Name: | Limb Salvage System |
| Classification Name and Reference: | 21 CFR 888.3510 Prosthesis, Knee, Femorotibial,Constrained, Cemented, Metal/Polymer – Class II |
| Device Product Code and Panel Code: | Orthopedics/87/KRO |
DEVICE INFORMATION
A. INTENDED USE
The REPIPHYSIS™ prosthesis is indicated for cemented procedures where radical resection and replacement of the distal femur and/or proximal tibia is required with the following conditions:
-
- patients suffering from severe arthropathy of the knee that does not respond to any conservative therapy or better alternative surgical treatment;
-
- surgical intervention for severe trauma, revision knee arthroplasties, and/or oncology indications.
-
- metastatic diseases (e.g., osteosarcomas, chondrosarcomas, gaint cell tumors, bone tumors)
The REPIPHYSIS™ Limb Salvage System components are for single use only.
Image /page/0/Picture/13 description: The image shows the logo for Wright Medical Technology, Inc. The logo features a stylized "W" symbol above the word "WRIGHT" in a bold, serif typeface. Below the name is the text "MEDICAL TECHNOLOGY, INC." in a smaller, sans-serif font. The overall design is simple and professional.
Image /page/0/Picture/14 description: The image shows a black and white drawing of the Earth. The Earth is partially illuminated, with the continents of Australia and Asia visible. There is a curved line above the Earth, which may represent the atmosphere or a satellite orbit.
{1}------------------------------------------------
K02148a
Page 2 of 4
B. DEVICE DESCRIPTION
BACKROUND DESCRIPTION
Malignant bone tumors in children often occur in the long bones, at or near the joints (shoulder, hip, and knee). Removal of the tumor often requires removal of part or the entire joint. Because the joint is where the growth of the limb occurs, one of the major problems in saving the limb in young growing children involves the ability to maintain equal lengths of the operated arm or leg with the unoperated side. Many attempts have been made to design a prosthesis, which could be easily expanded either without surgerv or through a very minor surgical procedure. Most of these designs have had mechanical difficulty or the lengthening procedure becomes a major surgical effort. The REPIPHYSISTM Limb Salvage System the complications that are known to occur with repeated operations. Once the prosthesis is fully implanted, the noninvasive lengthening of the prosthesis is activated by an external electromagnetic field.
The REPIPHYSISTM Limb Salvage System (Wright Medical Technology, Arlington, Tennessee) was previously named the Phenix Growing Prosthesis (Phenix Medical, Paris, France). The Phenix Growing Prosthesis was designed in France in the early 1980s. More than 100 patients have been treated with Phenix Growing Prosthesis in the last 20 years.
IMPLANT DESCRIPTION
The REPIPHYSIS™ Prosthesis is custom assembled for each patient. The REPIPHYSIS™ is implanted the same way as any other joint replacement device using non-allergic, standard materials that have been tested in biological situations. The REPIPHYSIS™ Limb Salvage Prosthesis Kit consists of the following components:
Distal Hinge Femur
The femoral housing is the main body of the distal hinge femoral portion of the implant. The most distal end of the femoral housing forms the outer components of the femoraltibial hinge. It internally houses the following various components of the expansion mechanism.
Tibial Base
The tibial base provides fixation to the proximal tibia. It consists of a cylindrical stem portion, which extends into the proximal tibial medullary canal. The more proximal portion of the tibial base has a flat plate that rests on the patient's tibial plateau region. On the underside of this plate are two small tabs that protrude down into the tibial plateau for rotational stability. On the top of this plate is the inner component of the femoral-tibial hinge mechanism.
Axial Bushing
The axial bushing goes inside the center hinge portion of the tibial base. This bushing is held in place by the two outer hinge features of the femoral housing. This bushing supplies the wear surface through which forces are transmitted between the femoral and tibial components and around which rotation occurs.
Image /page/1/Picture/13 description: The image shows the logo for Wright Medical Technology, Inc. The logo features a stylized "W" symbol above the word "WRIGHT" in a bold, sans-serif font. Below "WRIGHT" is the text "MEDICAL TECHNOLOGY, INC." in a smaller, sans-serif font, underlined by a thin line.
Image /page/1/Picture/14 description: The image shows a black and white drawing of a celestial body, possibly a planet or moon. The surface has a rough texture with dark and light patches, suggesting craters or other geological features. A curved line at the top indicates the edge of the sphere, and a small, dark shape is visible at the bottom, possibly a shadow or another object.
-510(K) SUMMARY
{2}------------------------------------------------
Axial Pin
The axial pin is introduced through the outer hinge portion of the distal femoral housing and into the axial bushing, which is contained in the center hinge portion of the tibial base. It extends through the other side of the outer hinge mechanism of the femoral housing. The axial pin mates with the outer hinge portions of the distal femoral housing and the inner diameter of the axial bushing. The axial pin is the pivot for the femoraltibial hinge mechanism.
INSTRUMENT DESCRIPTION
The REPIPHYSIS™ prosthesis is implanted the same way as any other Limb Salvage System.
In addition the REPIPHYSIS™ prosthesis uses an external electro-magnetic transmitter to activate the implant lengthening mechanism. The REPIPHYSIS Transmitter Unit operates by producing an electrical current in an inductor coil, which in turn generates a strong electro-magnetic field in the vicinity of the coil. When an electrically conductive material is placed within this electro-magnetic field, an electrical current is induced in the conductive material. If the proper conditions are established, this electrical current is sufficient to cause significant heating in this material.
OPERATION DESCRIPTION
The REPIPHYSIS™ prosthesis is implanted the same way as any other Limb Salvage System.
The lengthening technique for the REPIPH YSIS™ prosthesis is briefly described below:
The REPIPHYSIS™ prosthesis consists of two tubes with a spring mechanism contained in the larger tube (Exhibit 11: Photo of the Femoral Housing and sub-components). It is maintained compressed by a polyacetal locking mechanism. One tube is connected to the stem of the implant, and the second comprises the hinge portion of the hinge prosthesis. The uninvolved side of the joint is minimally resurfaced with a press-fit stem to attempt to preserve function of the non-involved growth plate. Expansion is achieved via exposure to an external electromagnetic field around the extremity. The coil transmits an electromagnetic field around the implant in the vicinity of the v-shaped flange of the spring housing tube. This generates an electrical current within the flange of the spring housing tube and is focused on the receiving antennae within the implant itself. This antenna is heated by the electromagnetic field. The heated element softens the surrounding polyacetal locking mechanism, which allows the spring expansion. The spring expansion pushes the two tubes apart from each other, thus lengthening the overall length of the leg. As skeletal growth occurs on the contralateral side, a discrepancy in the overall length of the two legs occurs. Follow-up scanograms quantify the discrepancy. Once a .5- to 1.0-cm discrepancy has occurred, the patient is taken to the fluoroscopy suite and remains awake without sedation or anesthesia. The receiving antennae within the implant are identified under fluoroscopy guidance and the skin is marked. The electromagnetic device is then applied over the receiving antennae, and the patient
Image /page/2/Picture/10 description: The image shows the logo for Wright Medical Technology, Inc. The logo features a stylized "W" symbol above the word "WRIGHT" in a bold, sans-serif font. Below the word "WRIGHT" is the text "MEDICAL TECHNOLOGY, INC." in a smaller, sans-serif font. A thin line underlines the text "MEDICAL TECHNOLOGY, INC."
Image /page/2/Picture/11 description: The image shows a black and white drawing of a planet. The planet has a rough, textured surface with dark and light areas. There is a ring around the planet, and a small object is visible below it. The drawing is simple and lacks detail, giving it a somewhat abstract appearance.
{3}------------------------------------------------
K021489
Page 4 of 4
activates the device for a period of approximately 15 seconds. A radiograph using magnification markers is then obtained of the level of the spring to determine how much lengthening has occurred. Once the desired amount of lengthening (typically 0.5 to 1cm) is achieved, the process is stopped. One or two activation processes are required to achieve the desired lengthening. The procedure is halted if the patient experiences any discomfort or anxiety. Follow-up radiographs are scheduled at 2 to 3-month intervals until the next lengthening is required.
C. SUBSTANTIAL EQUIVALENCE INFORMATION
The intended use, material, type of interface, and design features of REPIPHYSISTM Limb Salvage System are substantially equivalent to the competitive devices previously cleared for market. The safety and effectiveness of the REPIPHYSIS™ Limb Salvage System are adequately supported by the substantial equivalence information, materials data, and testing results provided within the Premarket Notification.
Image /page/3/Picture/4 description: The image shows the logo for Wright Medical Technology, Inc. The logo features the word "WRIGHT" in large, bold, sans-serif font. Above the word "WRIGHT" is a stylized "W" symbol. Below the word "WRIGHT" are the words "MEDICAL TECHNOLOGY, INC." in a smaller font.
{4}------------------------------------------------
DEPARTMENT OF HEALTH & HUMAN SERVICES
Image /page/4/Picture/1 description: The image shows the seal of the Department of Health & Human Services (HHS) of the United States. The seal features a stylized caduceus, a symbol often associated with medicine and healthcare, with a double helix-like design. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" is arranged in a circular pattern around the caduceus.
Public Health Service
DEC 04 2002
200 Cornorate Roulevard
Ehab M. Esmail Manager, Regulatory Affairs Wright Medical Technology, Inc. 5677 Airline Road · Arlington, Tennessee 38002
Re: K021489
Trade/Device Name: REPIPHYSIS™ Limb Salvage System Regulation Number: 21 CFR 888.3510 Regulation Name: Knee joint femorotibial metal/polymer constrained cemented prosthesis Regulatory Class: Class II Product Code: KRO Dated: November 18, 2002 Received: November 19, 2002
Dear Mr. Esmail:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You mav, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
{5}------------------------------------------------
Page 2 – Mr. Ehab M. Esmail
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594 4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html
Sincerely vours.
Celia M. Witten, Ph.D., M.D. Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
{6}------------------------------------------------
Image /page/6/Picture/0 description: The image shows a logo with a large letter W on the left side. To the right of the W is the text "WRIG" on the first line and "MEDICAL TECHN" on the second line. Below that is the address "5677 AIRLINE" and "ARLINGTON,," followed by the phone number "901-867".
K021489
Page 1 of 1
REPIPHYSIS™ Limb Salvage System
INDICATIONS STATEMENT
Limb salvage surgery is indicated for cemented procedures where radical resection and replacement of the distal femur and/or proximal tibia is required with the following conditions:
-
- patients suffering from severe arthropathy of the knee that does not respond to any conservative therapy or better alternative surgical treatment;
-
- surgical intervention for severe trauma, revision knee arthroplasties, and/or oncology indications.
- metastatic diseases (e.g., osteosarcomas, chondrosarcomas, gaint cell tumors, bone 3. tumors)
for Mark A. Millburn
(Division Sign-Off)
Division of General. Restorative and Neurological Devices
510(k) Number K031489
Image /page/6/Picture/11 description: The image shows the logo for Wright Medical Technology, Inc. The logo features a stylized "W" symbol above the word "WRIGHT" in a bold, sans-serif font. Below the word "WRIGHT" are the words "MEDICAL TECHNOLOGY, INC." in a smaller, sans-serif font.
Image /page/6/Picture/12 description: The image shows a black and white photograph of a person's head and shoulders. The person appears to be wearing a dark garment, and their face is partially obscured by shadows. The background is blurred, but it seems to be an indoor setting. The image has a grainy texture, which suggests that it may have been taken with an older camera or that it has been digitally altered.
-INDICATIONS STATEMENT
§ 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.