FOUNDATION 9MM FORGED CEMENTED STEM

K961890 · Encore Orthopedics, Inc. · JDI · Jun 14, 1996 · Orthopedic

Device Facts

• Record ID: K961890
• Device Name: FOUNDATION 9MM FORGED CEMENTED STEM
• Applicant: Encore Orthopedics, Inc.
• Product Code: JDI · Orthopedic
• Decision Date: Jun 14, 1996
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 888.3350
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

The Foundation 9 mm Forged Cemented Stem is intended for treatment of patients who are candidates for total or hemi-hip arthroplasty. The indications for use of the total hip replacement prosthesis include: noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis; rheumatoid arthritis; correction of functional deformity; revision procedures where other treatments where devices have failed; and treatment of nonunion, femoral neck and trochanteric fractures of the proximal femur with head involvement, which is unmanageable using other techniques. It is intended to be used with cement with acetabular components or with unipolar heads.

Device Story

Foundation Non-Porous Stem; cemented total hip prosthesis. Proximal body features trapezoidal geometry, anterior/posterior ribs, and PMMA buttons for 1.5 mm cement mantle centering. Distal portion conical with flanged PMMA canal centralizer. Fabricated from forged CoCrMo alloy; grit-blasted proximal surface (4-6 μ). Includes calcar collar and Morse taper for modular heads; 132° neck/stem angle. Used by orthopedic surgeons in clinical/OR settings for hip arthroplasty. Provides structural replacement for femoral component; restores joint function; facilitates fixation via bone cement.

Clinical Evidence

Bench testing only. Fatigue load testing performed; device survived 3300 N load. Laboratory testing conducted on Morse type taper.

Technological Characteristics

Material: Forged CoCrMo alloy. Geometry: Trapezoidal proximal body, conical distal stem. Features: Proximal ribs, PMMA centering buttons, distal flanged PMMA canal centralizer, calcar collar, Morse taper. Surface: Grit-blasted (4-6 μ). Angle: 132°. Fixation: Cemented.

Indications for Use

Indicated for patients requiring total or hemi-hip arthroplasty due to noninflammatory degenerative joint disease (osteoarthritis, avascular necrosis), rheumatoid arthritis, functional deformity, failed prior treatments, or nonunion/fractures of the proximal femur.

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

• Foundation® Forged Cemented Stems (K952191)

Submission Summary (Full Text)

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JUN 14 1996
K961890

# Summary of Safety and Effectiveness

Encore Orthopedics®, Inc.
8920 Business Park Drive
Suite 380
Austin, TX 78759
512-795-8696
J.D. Webb

**Trade Name:** Foundation™ Non-Porous Stem
**Common Name:** Cemented total hip
**Classification Name:** Hip joint metal/polymer semi-constrained cemented prosthesis per 21 CFR 888.3350

**Description:** The proximal body of the Foundation™ Non-Porous Stem is trapezoidal in cross-sectional geometry and tapers proximal to distal and lateral to medial. The proximal body has two ribs on the anterior and posterior surfaces that run the length of the proximal body. Polymethylmethacrylate “buttons” are placed on the anterior, posterior, lateral and medial surfaces of the proximal body to assure that the implant is centered in the metaphseal region of the femur with a 1.5 mm cement mantle. The proximal body of the femoral stem is grit blasted to a surface of 4-6 μ. This device is fabricated from forged CoCrMo alloy.

The distal portion of the stem is conical in shape. It necks down at the distal end to receive a flanged PMMA canal centralizer. This centralizer assures that the distal stem is centered in the femoral canal and helps to maintain a even cement mantle around the distal stem. The Foundation 9 mm Forged Cemented Stem has a calcar collar and has a Morse type taper to receive modular heads. The neck/stem angle is 132°.

**Intended Use:** The Foundation 9 mm Forged Cemented Stem is intended for treatment of patients who are candidates for total or hemi-hip arthroplasty. The indications for use of the total hip replacement prosthesis include: noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis; rheumatoid arthritis; correction of functional deformity; revision procedures where other treatments where devices have failed; and treatment of nonunion, femoral neck and trochanteric fractures of the proximal femur with head involvement, which is unmanageable using other techniques. It is intended to be used with cement with acetabular components or with unipolar heads.

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Encore Orthopedics, Inc.
510(k) Submission
Foundation™ 9mm Forged Cemented Stem

**Comparable Features to Predicate Device(s):** Features comparable to predicate devices include the Foundation® Forged Cemented Stems approved for commercial distribution in K952191, CoCrMo substrate, distal femoral canal centralizer, proximal cement spacers, calcar collar, proximal ribs on body, roughened proximal body, modular heads and unipolar heads.

**Test Results:** This stem survived a fatigue load of 3300 N.

Laboratory testing of the Morse type taper was conducted.