In orthopedic surgery, having power tools that can perform consistently regardless of the procedure time makes all the difference in the world. If you don't cut or shave bone appropriately for an implant, that implant will fail every time. The good news is surgical power tools have come a long way. Even in just the past six months or so, I've seen some really exciting developments in power, sharpness and precision. Here's a look at the latest offerings from the leading manufacturers.

Cutting the cord
Cordless, battery-powered surgical tools have several advantages over their pneumatic and electric cousins. From a clinical standpoint, sterility is probably the biggest benefit: There's no electrical cord or nitrogen hose to worry about when you're trying to prevent contamination in the surgical field. Going cordless can also increase the surgical team's mobility and reduce clutter in the OR.

However, the nickel cadmium batteries used to power these cordless devices have their downsides, particularly if you're going to use them for several different types of procedures with varying surgical times. Nickel-based batteries have "memories." If you use the same battery-powered drill for the same three-minute procedure 10 times in a row without recharging, that battery will "remember" that it only has to run for three minutes at a time. Even after you charge it, the battery might not be able to perform reliably for a longer procedure down the road. Nickel cadmium batteries also have a short shelf life, so if you don't use them within a week of recharging, they're not going to perform at peak capacity.

Luckily, manufacturers are working on developing new surgical drills and saws that can run on lithium ion batteries, which have a higher energy density but are smaller and lighter. Lithium ion batteries don't have a memory — every time they charge, they charge to their full capacity. They also hold the charge for longer periods of time on the shelf and run longer when they are in use. With our current instruments, we take the batteries off the drill, sterilize them separately using a special hydrogen peroxide sterilizer and then recharge them. The new lithium ion batteries, which aren't available yet but are in development, are supposed to be suitable for steam sterilization along with the drill, which is another benefit. (For more on the distinction between different types of batteries, go to www.batteryuniversity.com.)

Even though I'm partial to the benefits of cordless surgical tools, it's important to understand that they're not practical (or even available) for every procedure. For some specialties that require high speeds but low torque, such as neurosurgery, electric-powered tools may be preferable. One of the unique benefits of the corded tools we have is that they are customizable: Before a case, you can program the motor console for a certain amount of speed and torque according to the surgeon's preference and the demands of that particular procedure. This eliminates the need to adjust the power intraoperatively, thereby improving case efficiency. Whatever you can do to make your time more efficient in the OR — whether it's by eliminating cumbersome cords or customizing your tools in advance — is an added bonus for the patient, both in terms of the care he's receiving and in pure dollars and cents.

Easy to handle
Manufacturers are clearly starting to recognize that not all physicians (or physician assistants) are men, and even the biggest, burliest docs can get fatigued when holding a large drill for a long case. Several companies have come out with smaller, lighter drills that fit more comfortably into smaller hands and can be held for longer periods of time without straining the user's arms and shoulders. Lighter batteries are also making cordless, hand-held instruments more user-friendly. Fewer pedals on the floor make for a safer OR environment and allow more range of movement around the surgical site.

Balance of power
Imagine a 2 x 4 piece of wood. If you take a nail and drive it in, no matter what, the wood's going to split. But the more speed and power you put behind the hammer, the cleaner the break will be. The same laws of physics apply to surgical power tools. Every time the manufacturers come out with a new line of tools, they're likely to boast higher speeds (measured in cuts per minute for saws and rotations per minute for drills) and greater torque. But when it comes to surgical power tools, remember that balance is just as important as the rate of speed and torque. When evaluating a new drill or saw, consider the specialties and procedures for which it'll be used.

For example, neurosurgical procedures in which the physician will have to drill into the neck to get to the spine require high speed (around 60,000 rpm) but low torque. On the other hand, larger orthopedic drills can function well at lower speeds but require a higher level of torque to make a clean cut through dense bone. The right balance of speed and torque is particularly important for implant procedures. You don't want to burn any excess bone or waste any tissue that the patient's going to need for the implant to take.

In addition to faster, more powerful tools, there are some exciting developments in blade technology, such as new oscillating saw blades that come sandwiched between two outer blades. The outer blades, which remain still while the center blade oscillates at a very high speed, help keep the blade from jumping around and cutting anything but the desired target.

PRODUCT ROUNDUP

On the Cutting Edge of Surgical Power
Here's a snapshot of the next generation of tools and power sources from some of the leading manufacturers. — Compiled by Irene Tsikitas

Microspeed Uni by Aesculap
This electric power system features powerful, ergonomic 150-watt motors for precise bone dissection, a touchscreen control box with irrigation and two motor connections, and both high- and low-speed applications, says the company. It can be used for all applications except large bone. $30,000 to $40,000, www.aesculapusa.com

Cordless Driver 3 and SABO Micro Battery Power by Stryker Instruments
Small in size and weight, the Cordless Driver 3 offers a high level of mechanical balance and power for all surgical applications, particularly trauma and smaller bone surgery. www.stryker.com

Disposable Wire Driver by BioAccess
Disposable power tools from BioAccess are primarily designed for orthopedic procedures that can be done in an office or procedure room. They can sit on the shelf for up to five years and be ready for use within several minutes, says the company. $293, www.bioaccess.com

MPower2 by ConMed/Linvatec
Use this system of four battery-powered handpieces (two drills, an oscillating saw and a reciprocating saw) and a sternum saw for both large- and small-bone procedures, says ConMed/Linvatec. Triple-sealed technology in the handpiece protects the device from moisture, especially when using a washer/sanitizer. www.linvatec.com

Integrated Power Console
(IPC Platform) and Spine Disc Shaver by Medtronic The Integrated Power Console is the next-generation electric platform for Medtronic's powered handpieces for spinal, cranial and ENT surgery, says the company. The Spine Disc Shaver, powered by the IPC system, provides fast, powered nucleus removal during spinal surgeries. $17,849 for the IPC kit; $16,000 for the Spine Disc Shaver handpiece, www.medtronic.com

Lever Arm Motor Unit by OsteoMed Corporation
The lever on this fully autoclavable motor unit lets you adjust the speed range, motor direction and safety settings, says OsteoMed. The device's ergonomic shape also gives the user control and sensory feedback. www.osteomed.com

Series 7000 Large Power
Battery System by MicroAire Surgical Instruments This battery system for total joint arthroplasty, trauma and general orthopedics is powered by Nickel Metal Hydride (NiMH) batteries, which the company says have 30 percent more power and last three times as long as the leading competitor's. The autoclavable battery pack comes with a one-year warranty. www.microaire.com