← Product Code [HBB](/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/HBB) · K953434

# MIDAS REX MOTORS, (MIDAS I, MIDAS II & CONVERTIBLE MODELS) (K953434)

_Midas Rex Pneumatic Tools, Inc. · HBB · May 16, 1996 · Neurology · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/HBB/K953434

## Device Facts

- **Applicant:** Midas Rex Pneumatic Tools, Inc.
- **Product Code:** [HBB](/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/HBB.md)
- **Decision Date:** May 16, 1996
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 882.4370
- **Device Class:** Class 2
- **Review Panel:** Neurology
- **Attributes:** Therapeutic

## Indications for Use

To provide power to operate removable rotating surgical cutting tools or drill bits on a patient's skull.

## Device Story

Midas Rex Motors (Midas I, Midas II, Convertible) are air-powered surgical motors; designed to drive rotating cutting tools or drill bits for cranial surgery. System components include stainless steel/aluminum/brass motor housing, air supply hose, and joint connectors. Operates at 20-120 psi or 200 psi. Features include optional rotating cuffs at joints to allow independent swivel of motor and hose, preventing kinking. Used in clinical surgical settings by physicians. Device provides mechanical power to surgical attachments; enables bone/tissue cutting. Supplied non-sterile; requires hospital-performed sterilization (steam or ethylene oxide) prior to use.

## Clinical Evidence

Bench testing only. Performance characteristics (RPM, stall torque) compared to predicate device demonstrate equivalent functional output.

## Technological Characteristics

Pneumatic motor; stainless steel, aluminum, and brass construction. Operating pressure: 20-120 psi or 200 psi. RPM: 30,000-75,000. Stall torque: 1-5.3 in-oz. Form factor: round or hexagonal casing (0.375, 0.5, or 0.75 inch diameter). Connectivity: air hose connection with optional swivel joints. Sterilization: compatible with ethylene oxide, high vacuum steam (270° F), and gravity displacement steam (250° F or 270° F).

## Regulatory Identification

A pneumatic cranial drill motor is a pneumatically operated power source used with removable rotating surgical cutting tools or drill bits on a patient's skull.

## Predicate Devices

- Midas Rex Whirlwind™ Motor (pre-1976)

## Reference Devices

- Midas Rex Motors ([K952300](/device/K952300.md))

## Submission Summary (Full Text)

> This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com.
>
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K953434

# 510 (k) SUMMARY

MAY 16 1995

## I. ADMINISTRATIVE

Submitter: Midas Rex Pneumatic Tools, Inc.
3001 Race Street
Fort Worth, Texas 76111
(817) 831-2604

Contact Person: Forest Barber, Jr.

Date of Preparation: July 20, 1995

## II. DEVICE NAME

Proprietary Name: Midas Rex Motors (Midas I, Midas II and Convertible Models)

Common Name: Surgical Instrument Motor

Classification Name: Pneumatic Cranial Drill Motor (84HBB)

## III. PREDICATE DEVICE

Midas Rex Whirlwind™ Motor, legally marketed prior to May 28, 1976.

## IV. DEVICE DESCRIPTION

The Midas Rex Motors (Midas I, Midas II and Convertible models) are air-powered, rotating motors designed to operate at 20-120 psi or at up to 200 psi. The motor is connected to an air-supply source by means of a stainless steel joint and a plastic air hose with inner rubber pressure hose.

The motors are constructed of stainless steel, aluminum and brass and are designed to operate at 20-120 psi or at up to 200 psi with the same performance characteristics. Depending on user preference, the 200 psi motor is available in either a round or hexagonal casing, approximately 0.75 inch in diameter. Similarly, the 120 psi motor can be supplied in either a round or hexagonal casing in diameters of approximately 0.375, 0.5 or 0.75 inch.

Again depending on user preference, the joint connecting the motor to the air hose can be equipped with a rotating cuff at one or both ends, allowing the motor and/or air hose to swivel independently with respect to the joint, thus providing greater freedom of movement during surgical procedures and avoiding possible "kinking" of the air hose. Thus, a variety of device configurations are possible based on the surgeon's personal preference, as shown below:

Premarket Notification: Midas Rex Motors

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|   | Motor | Joint | Hose  |
| --- | --- | --- | --- |
|  Midas I | Fixed | Straight (180°) | Fixed  |
|   |  Swivels | Straight (180°) | Swivels  |
|  Midas II | Fixed | Angled (45°) | Fixed  |
|   |  Fixed | Angled (45°) | Swivels  |
|   |  Swivels | Angled (45°) | Fixed  |
|   |  Swivels | Angled (45°) | Swivels  |
|  Convertible | Fixed | 180° or 45° | Fixed  |
|   |  Fixed | 180° or 45° | Swivels  |
|   |  Swivels | 180° or 45° | Fixed  |
|   |  Swivels | 180° or 45° | Swivels  |

Midas Rex Motors are supplied non-sterile for sterilization by hospital staff immediately prior to each use. The materials of construction of the motor and air hose are compatible with both ethylene oxide and steam sterilization (flash or standard autoclave procedures). A 4-minute cycle is recommended for high vacuum steam sterilization at 270° F. Gravity displacement steam sterilization may be performed at 250° F for 35 minutes or at 270° F for 15 minutes. A minimum of 18 hours mechanical aeration is recommended following ethylene oxide sterilization.

## V. INTENDED USE

To provide power to operate removable rotating surgical cutting tools or drill bits on a patient's skull.

## VI. COMPARISON TO PREDICATE DEVICES

See Table.

Premarket Notification: Midas Rex Motors

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Table of Comparison to Legally Marketed Device

|   | Midas I | Midas II | Convertible | Midas I, II and Convertible (K952300) | Whirlwind™ (pre-1976)  |
| --- | --- | --- | --- | --- | --- |
|  Construction | Stainless steel, brass and aluminum | Stainless steel, brass and aluminum | Stainless steel, brass and aluminum | Stainless steel, brass and aluminum | Stainless steel, brass and aluminum  |
|  Case Shape/Diameter | Round or hexagonal: 0.375, 0.5 or 0.75 inch | Round or hexagonal: 0.375, 0.5 or 0.75 inch | Round or hexagonal: 0.375, 0.5 or 0.75 inch | Round or hexagonal: 0.375, 0.5 or 0.75 inch | Round/0.75 inch  |
|  Motor/Air hose Joint | Straight | Angled (45°) | Straight or Angled (swivel joint) | Straight, Angled and Swivel Joint | Straight  |
|  Motor Alignment (relative to joint) | Fixed or Swivel | Fixed or Swivel | Fixed or Swivel | Fixed or Swivel | Fixed  |
|  Hose Alignment (relative to joint) | Fixed or Swivel | Fixed or Swivel | Fixed or Swivel | Fixed or Swivel | Fixed  |
|  Air Operating Pressure | 20-120 psi or 200 psi | 20-120 psi or 200 psi | 20-120 psi or 200 psi | 20-120 psi or 200 psi | 200 psi  |
|  RPM (000's) | 40-75 (20-120 psi)
30-75 (200 psi) | 40-75 (20-120 psi)
30-75 (200 psi) | 40-75 (20-120 psi)
30-75 (200 psi) | 40-75 (20-120 psi)
30-75 (200 psi) | 30-75  |
|  Stall Torque | 1-5.3 (20-120 psi)
1.3-5.3 (200 psi) | 1-5.3 (20-120 psi)
1.3-5.3 (200 psi) | 1-5.3 (20-120 psi)
1.3-5.3 (200 psi) | 1-5.3 (20-120 psi)
1.3-5.3 (200 psi) | 1.3-5.3  |
|  Intended Use | To provide power to operate removable rotating surgical cutting tools or drill bits on a patient's skull. | To provide power to operate removable rotating surgical cutting tools or drill bits on a patient's skull. | To provide power to operate removable rotating surgical cutting tools or drill bits on a patient's skull. | To provide power to operate various accessories or attachments to cut hard tissue or bone and soft tissue. | To provide power to operate various accessories or attachments to cut hard tissue or bone and soft tissue.  |

Premarket Notification: Midas Rex Motors

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**Source:** [https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/HBB/K953434](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/HBB/K953434)

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