A Medical Device Daily

DePuy Orthopaedics (Warsaw, Indiana), a leading producer of devices for joint replacement and trauma, reported the launch of the aSphere M-Spec Femoral Head, a new metal hip bearing option that potentially reduces cumulative wear by 80% and associated ion release by 77% compared with conventional metal-on-metal technology.

The announcement was made during at the 76th annual meeting of the American Academy of Orthopaedic Surgeons (AAOS; Rosemont, Illinois) in Las Vegas.

DePuy said this advancement in metal bearing technology is the result of its continued investment in bearing design and manufacturing. Precision-contoured aSphere heads approximate the shaping that occurs during the in-the-body run-in wear phase.

The company said this new design incorporates a wear-resistance zone, so patients may experience a substantial decrease in metal wear debris and ion release when compared to conventional metal-on-metal designs.

The aSphere head, combined with DePuy's TrueGlide technology, facilitates a more fluid range of natural motion and up to 159 degrees range of motion, the company said. The aSphere head was cleared for marketing by the FDA in December, adding another advanced option to DePuy's Pinnacle Hip Solutions bearing system.

All DePuy metal-on-metal bearings feature TrueGlide technology, which the company said "enhances performance with smooth, natural motion and less friction."

Advanced tribology is the science behind this innovation, it said, and is the main reason for improved wear resistance over conventional technology.

TrueGlide technology optimizes the diametrical clearance and surface finish of the implant, allowing the body to create a thin film of synovial fluid, enabling bearing lubrication and reducing wear. The result, according to DePuy, is a smooth, more fluid range of natural motion.

"In addition to improved wear and ion release, the Pinnacle System's aSphere M-Spec Femoral Heads provide optimized head-to-shell ratios, which may enhance stability and long-term performance," said Mark Hanes, PhD, worldwide director of research at DePuy Orthopaedics.

The company said the aSphere head is compatible with its complete line of advanced femoral stems to provide surgeons greater flexibility based on their preferred technique and the patient's anatomy.

David Floyd, U.S. president of DePuy Orthopaedics, said, "The aSphere head is the latest example of our commitment to innovation that continues to optimize our premier high-stability and low-wear solutions."

DePuy also reported the launch at AAOS of the Anatomic Locked Plating Systems (A.L.P.S.) for hand and distal fibula fractures.

The company said the A.L.P.S. Hand Fracture System and A.L.P.S. Composite Locking Plate System "offer anatomically-designed titanium plating technology utilizing low-profile, high-strength plates. These plates provide the flexibility of in situ contourability to mimic the patient's natural anatomy and multiple screw and fixation options."

The company said the low-profile design helps minimize discomfort and soft tissue irritation.

DePuy said the A.L.P.S. Hand Fracture System is its first plating system for complex fractures of metacarpal and phalangeal bones. It said the system's "uniquely contoured plates mimic the anatomy of the fingers and are available in five styles that can be used to treat a wide range of fractures, using titanium alloy and cobalt chrome screws for strong and stable fixation."

The company said the low-profile design, strength and stability of the A.L.P.S. Composite Locking Plate System "make it particularly well-suited for distal fibula procedures, which often involve complex fractures and minimal tissue coverage." The small-fragment plate features a bulleted tip at the proximal end to facilitate insertion under the muscles of the lower leg.

Both plating systems come pre-loaded with DePuy disposable and color-coded Fixed Angle Screw Targeting Guides (F.A.S.T. Guide inserts). The Guides direct the trajectory of the drill-bit through the plate to facilitate accurate screw placement after drilling the hole. DePuy said this has the potential to save time in the operating room, since no intra-operative assembly of the guides is required.

Also at AAOS:

• Salient Surgical Technologies (Portsmouth, New Hampshire) unveiled the Aquamantys Epidural Vein Sealer (EVS) bipolar device. The company said the EVS is designed to address the challenging anatomy in minimally invasive spine surgery and is the latest product introduction on its Aquamantys platform.

The EVS employs Transcollation advanced energy technology to "significantly reduce bleeding in hard-to-reach areas," according to Salient. "Reducing blood loss improves visualization for the surgeon, can result in improved clinical outcomes for the patient and may result in lower costs to the hospital."

The innovation of the EVS, the company said, is the ability to deliver Transcollation technology through miniaturized electrodes, which provide direct and precise compression of epidural veins around critical structures. The EVS is used with the same Aquamantys System Generator as Salient's standard 2.3 and 6.0 Bipolar Sealer devices.

• Smith & Nephew's Orthopaedic Reconstruction & Trauma (Memphis, Tennessee) business has released the Visionaire Patient Matched instrumentation for use in total knee replacement surgery.

The Visionaire's technology uses a patient's MRI and X-rays to create custom surgical instrumentation for use with the S&N portfolio of high-performance knee implants. By using instruments designed from each patient's anatomical data, surgeons can accommodate the unique shapes and angles of the joint while precisely aligning the implant.

• Smith & Nephew's Endoscopy Division (Andover, Massachusetts) reported the launch of the Osteoraptor Anchor for repair in the hip and shoulder. The company noted that during 2009, surgeons will perform an estimated 15,000 labral repair procedures in the hip joint and an estimated 185,000 procedures for the shoulder. Labral repairs are necessary when the labrum, the fibrous cartilage ring that rims the joint socket, tears or becomes stretched due to impingement or acute injury.

Damage to the labrum in the hip may be a source of chronic pain and may also contribute to osteoarthritis. In the shoulder, this damage can lead to instability where the upper arm bone slips out of the socket. In standard procedures, surgeons reattach the labrum to the bony socket of the joint using small anchors and suture.

S&N said the new Osteoraptor Anchor is the first hip anchor to use polylactic acid hydroxyapatite (PLLA-HA). The key ingredient, hydroxyapatite, is a mineral found naturally in bone. The company said studies have shown that the presence of HA increases the anchor's strength and introduces chemicals that promote the formation of a strong bond between the anchor and the bone surface.