Orthopedic Implants

Interspinous spacer

Interspinous spacers are orthopedic implants used in minimally invasive spine surgeries that treat lumbar spinal stenosis (LSS). LSS occurs when the space between the vertebrae is reduced, causing bone or tissue to come in contact with the spinal nerve. When a nerve in the lower back becomes pinched, it can cause pain, tingling, weakness, or numbness that radiates from the lower back into the buttocks and legs. LSS is a progressive disorder that in advanced stages can cause debilitating pain that limits the ability of patients to walk, leading to disability.

The spine surgeon gains access to the inter-vertebrae space via a small incision that minimizes damage to surrounding muscles and ligaments and then implants an interspinous spacer that lifts the vertebra off the pinched nerve without removing any bone and with minimal loss of blood. The Introduction of interspinous spacers can provide sustained relief.

STI used 4-axes laser tube cutting technology to machine interspinous spacers out of Titanium tubes (OD 5mm), including non-radial laser cutting of special elements. Laser seam welding was used for welding a bolt to the distal end of the device. Electropolishing gave the implant its final finish.

Orthopedic nails for intramedullary fixation

Orthopedic nails are intramedullary implants used in long bone, minimally invasive reconstruction surgeries for fixing bone fractures resulting from trauma or osteoporosis.

Most orthopedic nail systems use bolts to “lock” the nail into position on both ends of the fracture. Advanced intramedullary fixation systems use expandable nails that do not require interlocking screws. The orthopedic surgeon inserts the nail in its reduced form through the medullary canal and pushes it into position. Then, the surgeon pumps saline solution into the hermetically sealed nail. As the liquid pressure increases, the nail expands to the desired diameter in a controlled manner.

STI provides laser welding services for assembling intramedullary nails from various metal components, including mix metal welding of hardened bars on annealed tubes, laser seam welding of both the distal tip and the proximal end. Quality assurance procedures include pressure, sealing and leakage tests to verify hermetic sealing and metallographic cross section analysis to inspect welding quality. Electropolish process, optimized for stainless steel and the specific product requirements, provides a shiny surface finish and improves biocompatibility and corrosion resistance.