NATURAL HIP SYSTEM

K960258 · Intermedics Orthopedics · JDI · Jul 12, 1996 · Orthopedic

Device Facts

• Record ID: K960258
• Device Name: NATURAL HIP SYSTEM
• Applicant: Intermedics Orthopedics
• Product Code: JDI · Orthopedic
• Decision Date: Jul 12, 1996
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 888.3350
• Device Class: Class 2
• Attributes: Therapeutic

Indications for Use

The components of the Natural Hip System, like the predicate IOI and competitive devices, are intended for cemented application. In addition, the components of the Natural Hip System are intended for cementless application.

Device Story

Natural Hip System is a modular femoral hip prosthesis component. Device features include a wedge-shaped proximal geometry for femoral canal fit, optional proximal collar for cement pressurization, optional proximal PMMA spacers, and optional proximal anterior/posterior normalizations to reduce subsidence. Distal portion includes a hole for a UHMWpe centralizer. Surface enhancement via grit blasting (63-149µ-inches) is applied to the proximal third or entire length below the collar to improve fixation in cemented or cementless applications. Device uses an IOI 12/14 Morse Taper trunnion for femoral head attachment. Available in 9 sizes. Used by orthopedic surgeons in total hip arthroplasty procedures to restore joint function and reduce pain. Clinical benefit derived from improved implant stability and fixation.

Clinical Evidence

No clinical data provided. Substantial equivalence is based on design, material, and technological characteristics compared to legally marketed predicate devices.

Technological Characteristics

Materials: Cast/Forged Cobalt Chromium alloy or Titanium alloy. Design: Modular femoral stem with 12/14 Morse Taper trunnion, wedge-shaped proximal geometry, optional proximal collar, optional proximal PMMA spacers, and distal UHMWpe centralizer. Surface: Grit-blasted (63-149µ-inches). Sizes: 9. Sterilization: Not specified.

Indications for Use

Indicated for patients with noninflammatory degenerative joint disease (e.g., avascular necrosis, osteoarthritis), inflammatory joint disease (e.g., rheumatoid arthritis), failed previous surgery with persistent pain/deformity/dysfunction, or revision of failed arthroplasty. Total hip replacement may be considered for younger patients if unequivocal indications outweigh age-related risks and modified activity/loading demands are assured.

Regulatory Classification

Identification

A hip joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a hip 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 an acetabular resurfacing component made of ultra-high molecular weight polyethylene and is limited to those prostheses intended for use with bone cement (§ 888.3027).

Predicate Devices

• Premier Total Hip Stem (K894051)
• Osteonics ODC Cemented Hip Stem
• Osteonics ODC Hip Stem
• PFC Cemented Hip Stem (Johnson & Johnson Orthopaedics)
• Perfecta IMC Stem (Orthomet Inc.)

Reference Devices

• IOI 12/14 Morse Taper configured trunnion (K913060)
• Zirconia bearing heads (K942330)
• Zirconia bearing heads (K942406)
• Distal centralizer (K913208)

Submission Summary (Full Text)

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K960258
JUL 12 1996
Intermedics Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

# 510(k) Premarket Notification
## Summary of Safety and Effectiveness for the Natural Hip System

In accordance with the Food and Drug Administration Interim Rule to implement provisions of the Safe Medical Devices Act of 1990 and in conformance with 21CFR 807, this is to serve as a 510(k) Summary for the components of the Natural Hip System.

**Submitter:**
Intermedics Orthopedics, Inc.
9900 Spectrum Drive
Austin, Texas, 78717
Tel.: [phone]
Fax: [phone]

**Contact Person:**
Jacquelyn Hughes
Manager, Regulatory Affairs

**Date:**
January 17, 1996

**Proprietary name:**
Natural Hip System

**Common Name:**
Artificial hip component

**Classification name:**
Class III → Jm Prosthesis, Hip, Semi-constrained, Metal/Ceramic/Polymer, Cemented or Non-Porous UnCemented Prosthesis 21CFR 888.3353)
*Handwritten note: 87 MAY 1*

**Predicate Devices:**
The features employed by the components of the Natural Hip System are substantially equivalent to the features employed by the following legally marketed predicate devices:

- **Premier Total Hip Stem:** Intermedics Orthopaedics Inc. (510(k) #K894051).
- **Osteonics ODC Cemented Hip Stem:** Osteonics Corporation (510(k) number unknown to IOI).
- **Osteonics ODC Hip Stem:** Osteonics Corporation (510(k) now to IOI).
- **PFC Cemented Hip Stem:** Johnson & Johnson Orthopaedics (510(k) number unknown to IOI).

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Intermedics Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

■ Perfecta IMC Stem: Orthomet Inc.
(510(k) number unknown to IOI).

## Device Description:

The components of the Natural Hip System employ an IOI 12/14 Morse Taper configured trunnion, available in either threaded or smooth (non-threaded) configuration, for the attachment of the IOI's femoral bearing heads, including the zirconia bearing heads. The IOI 12/14 Morse Taper configured trunnion has previously been determined substantially equivalent by the FDA via the 510(k) #K913060. In addition, the use of zirconia bearing heads with the IOI 12/14 Morse Taper configured trunnion have also previously been determined substantially equivalent by the FDA via 510(k) #s' K942330 and K942406. Please note that the components of the Natural Hip System with a smooth Morse Taper configured trunnion are not intended to be used with the ceramic bearing heads. Such a warning will be clearly stated on the IOI package insert accompanying the component of the Natural Hip System (See IOI's proposed package insert provided in Appendix A of this 510(k) premarket notification submission).

The components of the Natural Hip System are available with and without a proximal collar. The proximal collar enhances cement pressurization in a cemented total hip arthroplasty. The components of the Natural Hip System incorporate a wedged shaped geometry on the proximal area of the hip stem for enhanced fit of the device in a prepared femoral canal. The wedge shaped geometry is designed to reduce stresses that can potentially cause cement/bone or bone/prosthesis interface breakdown. The components of the Natural Hip System are available with or without normalizations in the proximal anterior and posterior regions of the hip stem. Normalizations are series of steps and walls which potentially reduce subsidence and medial migration. In

II

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Intermedics Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

addition, the proximal region of the components of the Natural Hip System are available with or without proximal polymethylmethacrylate (PMMA) spacers which provide an even cement mantle in a cemented total hip arthroplasty.

Surface enhancement via grit blasting is employed on either the proximal third or the entire length of the hip stem below the collar of the components of the Natural Hip System. Grit blasted surfaces provide enhanced fixation in both cemented and cementless total hip arthroplasties. The grit blasted surfaces provide a surface roughness of 63-149µ-inches. In a cemented application, the grit blasted surface provides greater cement interdigitation with bone cement. In a press-fit or cementless application, the grit blasted surfaces provide an enhanced bone/prosthesis interface.

The distal portion of the components of the Natural Hip System employs a hole for the attachment of a distal centralizer fabricated from UHMWpe. The distal centralizer has been previously determined substantially equivalent by the FDA via 510(k) #K913208.

The components of the Natural Hip System are available in 9 sizes (sizes 00 through 7).

## Intended Use:

The components of the Natural Hip System, like the predicate IOI and competitive devices, are intended for cemented application. In addition, the components of the Natural Hip System are intended for cementless application.

The Indications for Use for the components of the Natural Hip System are as follows:

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Intermedics Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

1. Patient conditions of noninflammatory degenerative joint disease (NIDJD), e.g., avascular necrosis, osteoarthritis, and inflammatory joint disease (IJD), e.g., rheumatoid arthritis.
2. Those patients with failed previous surgery where pain, deformity, or dysfunction persists.
3. Revision of previously failed arthroplasty.

Total hip replacements may be considered for younger patients if any unequivocal indication outweighs the risks associated with the age of the patient (see "Warnings and Precautions"), and modified demands regarding activity and hip joint loading are assured. This includes severely crippled patients with multiple joint involvement, for whom an immediate need of hip mobility leads to an expectation of significant improvement in the quality of their lives.

## Summary of Technological Characteristics:

The features of the components of the Natural Hip System are substantially equivalent to the aforementioned predicate IOI and/or competitive devices in terms of materials, intended use and design characteristics. A comparison of the features of the components of the Natural Hip System in terms of materials, intended use and design characteristics to the aforementioned legally marketed predicate devices is as follows:

## Materials:

Substantial equivalence in terms of materials is based upon the fact that both the subject devices and the legally marketed predicate devices are fabricated from either cobalt chromium alloy or titanium alloy.

IV

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Intermedica Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

## Intended Use:

The components of the Natural Hip System, like the predicate IOI and competitive devices, are intended for cemented application. The components of the Natural Hip System differ from the legally marketed predicate devices in that they are also intended for cementless application. The subject devices and the predicate devices share the same indications for use. Therefore, in terms of intended use the components of the Natural Hip System are substantially equivalent to the legally marketed predicate devices.

## Design characteristics:

The design characteristics of the components of the Natural Hip System are substantially equivalent to the predicate devices based upon the following;

- The components of the Natural Hip System like the aforementioned legally marketed predicate devices incorporate a wedged shaped geometry on the proximal area of the hip stem for enhanced fit in a prepared femoral canal.

- The components of the Natural Hip System like the predicate IOI’s Premier Total Hip stem and Orthomet’s Perfecta IMC Stem are available with the optional normalizations on the proximal third of the femoral stem

- The components of the Natural Hip System like the predicate Osteonics’ ODC Hip Stem and the ODC Fx Hip Stem are available without the optional normalizations on the proximal third of the femoral stem

- The components of the Natural Hip System like the aforementioned legally marketed predicate devices are available with proximal collar.

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Intermedics Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

Please note that the components of the Natural Hip System are also available, as an option to the surgeon, without the proximal collar.

- The components of the Natural Hip System like the predicate legally marketed IOI's Premier Total Hip Stem, Osteonics' ODC Hip Stem, Johnson & Johnson's PFC Cemented Hip Stem, and the Orthomet's Perfecta IMC Stem are available with the distal PMMA centralizer.

- The components of the Natural Hip System like the predicate legally marketed predicate IOI's Premier Total Hip Stem, Osteonics ODC Hip Stem, Johnson & Johnson's PFC Cemented Hip Stem, and the Orthomet's Perfecta IMC Stem employ grit blasted surface on the proximal third of the femoral stem. In addition, the components of the Natural Hip System, like the predicate Osteonics' ODC Fx Hip Stem, are available as an option with a grit blasted surface along the entire length below the collar of the hip stem.

Therefore, in terms of design characteristics the components of the Natural Hip System are substantially equivalent to the legally marketed predicate devices. Marketing literature on the aforementioned predicate devices is provided in Appendix D of this 510(k) premarket notification submission.

A side by side tabular comparison of the features of the components of the Natural Hip System to those of the predicate devices follows.

VI

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Intermedics Orthopedics, Inc.
510(k) Premarket Notification Submission: Natural Hip System

| Characteristics | Subject Devices
The components of the Natural Hip System | Predicate Devices | | | | |
| --- | --- | --- | --- | --- | --- | --- |
| | | Premier Total Hip Stem | ODC Px Hip Stem | ODC Hip Stem | PFC Cemented Hip Stem | Perfecta IMC Stem |
| Manufacturer | IOI | IOI | Osteonics | Osteonics | J & J | Orthomet |
| 510(k)# | - | K894051 | Unknown | Unknown | Unknown | Unknown |
| Material | Cast CoCr/
Forged CoCr/
Titanium alloy | Titanium alloy | Cast CoCr | Cast CoCr | CoCr alloy | Forged CoCr alloy |
| Application | Cemented/
Cementless | Cemented | Cemented | Cemented | Cemented | Cemented |
| Proximal anterior/posterior normalization. | Available with or without normalizations | Yes | No | No | No | Yes |
| Proximal wedge shaped design | Yes | Yes | Yes | Yes | Yes | Yes |
| Proximal PMMA centralizers | Available with or without PMMA centralizers | No | No | No | Yes | No |
| Distal PMMA centralizers | Yes | Yes | No | Yes | Yes | Yes |
| Proximal collar | Available with or without collar | Yes | Yes | Yes | Yes | Yes |
| Surface enhancement via grit blasting | Proximal third or entire length below the collar of the hip stem | Yes, but proximal third only | Yes, hip stem below the collar | Yes, but proximal third only | Yes, but proximal third only | Yes, but proximal third only |
| neck lengths | 25-41mm | 35mm | 25-35mm | 25-40mm | unknown | Unknown |
| sizes | 9 sizes | 7 sizes | 5 sizes | 7 sizes | 5 sizes | 6 sizes |

VII