UNIUM™ Small Bone and Trauma Power Tool

Andrew Sands, Michael Swords

The UNIUM™ Power Tool was designed for increased reliability, efficiency, and comfort of use for an enhanced surgical experience and improved outcomes. It is intended for use in traumatology and orthopedic surgery that may include drilling, reaming, burring, screwing, tapping, sawing, and setting pins and wires. 

The UNIUM Small Bone Power Tool consists of a modular handpiece for general use and a standalone reciprocating saw handpiece for cardiothoracic surgery (specifically for sternotomies). The strength and durability of both UNIUM Handpieces is enhanced by a high-quality PEEK housing and a stainless-steel coupling.

The system covers the following surgical areas: lower extremities (including intramedullary reaming but excluding acetabular reaming), pelvic, upper extremities, spine, sports medicine, and cardiothoracic.

UNIUM is a next generation small bone power tool that is approved by the AO Technical Commission and complies with the required standards for operating room use and addresses the needs of today’s healthcare professionals.

The system received AO TC approval for veterinary use in 2022.

Clinical problem

The use of power tools is closely associated with modern orthopedic surgery. These tools have advanced surgery by allowing surgeons to work efficiently and accurately. Pneumatic and electric power tools which require cords have been largely replaced by battery-operated devices because of their unconstrained and more comfortable use.

The battery-driven power tool Colibri II/Small Battery Drive II manufactured by DePuy Synthes has been available since 2012 (it is sold under the brand name Colibri II in Europe, Middle East, Africa, Asia Pacific, and Latin America, and under the brand name Small Battery Drive II in the US and Canada). Surgeons have long appreciated its ergonomic design, ease of use, and the high capacity delivered by the 14.4 V Lithium-Ion battery pack.

Since the initial launch of the Colibri II/Small Battery Drive II, the small bone surgery requirements have been evolving and increasing in complexity. In response, there is a need for improved devices which address the following essential demands:

  • Lightweight and compact design for precise handling and low hand fatigue.
  • Power, torque, and speed to match the broad range of applications in the small bone segment as well as heavy duty surgery.
  • The battery capacity should be sufficient to cover the whole surgery to avoid intraoperative battery change. The battery must deliver consistent performance.
  • Long lifetime and reliability of the system.

The Foot and Ankle Expert Group together with DePuy Synthes have developed an innovative power tool system that takes advantage of the latest technologies to fulfill these demands.


The UNIUM Handpiece is more powerful (100 W) than the Colibri II/Small Battery Drive II (85 W), although it weighs 175 g/0.39 lbs less (Fig 1). The increased power is expected to be beneficial for the performance in dense bone conditions (eg, in hindfoot arthritic bone and dense subtalar bone) and for reaming of long bones.

The trigger mechanism of the modular handpiece is different to that of the Colibri II/Small Battery Drive II and is in line with current industry standards. The lower trigger is for forward operation and the upper trigger for reverse operation. The oscillation mode is activated by pressing both triggers simultaneously. Additionally, the handpiece can be put in “forward only mode”.

The UNIUM Small Bone Power Tool is powered by an innovative Power Unit technology that incorporates the Electronic Control Unit and Li-Ion battery (Fig 2). These temperature sensitive parts are not exposed to steam sterilization, which extends the lifetime, reliability, and sustainability of the platform.

The UNIUM Modular Handpiece is compatible with all existing Colibri II/Small Battery Drive II attachments (Fig 3) (except for the K-wire attachment which has been updated as noted below), UBC II charger, and cutting tools for versatile use. UNIUM has a K-wire attachment with a range of Ø 0.6–3.2 mm. There is an increased output speed of up to a maximum of 1,700 rpm.

The standalone UNIUM Reciprocating Saw Handpiece was developed as a power tool for cardiothoracic applications (Fig 4). It was thoroughly tested and approved by the Thoracic Expert Group.

Hazards and labeling

Due to varying countries’ legal and regulatory approval requirements, consult the appropriate local product labeling for approved intended use of the products described on this website. All devices on this website are approved by the AO Technical Commission. For logistical reasons, these devices may not be available in all countries worldwide at the date of publication. 

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