Spinal instrumentation is used to stabilize the spine and carry out the procedure during minimally invasive spinal procedures. One major focus is lessening the pressure put on the spine until successful fusion has occurred. This ensures that bone growth does not occur in a way which further impedes proper movement, and that growth is as efficient as possible. Many of the same instruments used in standard spinal fusion may be used here.
Pedicle screws provide a means of stabilizing a spinal level during a fusion procedure. The screws themselves do not fixate the levels, but act as firm anchor points that can then be connected with a rod. Pedicle screws can be placed at two or more consecutive spine levels. A short rod is subsequently implanted in order to connect the screws. The screw and rod construct prevents motion at the levels that are being fused.
The purpose of spinal fusion is to grow one or more vertebral bodies together to form a fused bone in order to treat certain pathologies. Plates, posterior fixation devices and interbody devices exist to help stabilize the spine while it fuses and heals. Traditionally, these devices have been implanted through open surgery; however, a growing number of these devices are being implanted using minimally invasive surgery (MIS) techniques. MIS greatly reduces surgical damage to the patient and is much less invasive than an open procedure. MIS for spinal fusion is made possible by complex and innovative surgical technology, allowing implantation of posterior screw/rod and interbody devices with minimal surgical damage or harm to the patient.
Interbody (IB) devices are designed to replace the intervertebral discs of the spine; this enhances stability in the region and promotes fusion between the two vertebral bodies. These devices are threaded, allowing them to be used in conjunction with bone graft material. Over time, the packed graft is gradually replaced by natural bone, forming a solid piece. IB fusion procedures typically add a posterior fixation device to the associated level. These procedures are often referred to as 360° fusions, as surgeons will implant interbody devices from an anterior approach and flip the patient over to implant a posterior pedicle screw device. This combination increases the fusion success rate over standalone interbody fusion device implantation without the addition of fixation devices.
Orthopedic image guided surgery (IGS) systems are used in procedures such as total knee arthroplasty (TKA), total hip arthroplasty (THA), anterior cruciate ligament (ACL) reconstruction, trauma and corrective surgeries. During these reconstruction procedures, the alignment of the orthopedic implant is critical and IGS systems are capable of reaching the target alignment within +/- 3°, 95% to 98% of the time.
The market for spine navigation systems, or spinal image guided surgery (IGS) systems, is closely linked to that of neurosurgical IGS systems. There are relatively few dedicated IGS systems for spinal procedures. Most spinal IGS procedures are performed using neurosurgical IGS systems with spinal software applications. Because spinal and neurosurgical operations are often performed by the same surgeons, this arrangement has worked well so far. Certain spinal procedures may require specialized instruments; however, these disposable instruments can be used with non-specialized systems that have the appropriate software. Many spinal IGS systems can be used to assist in trauma procedures once equipped with the right software and accessories. Spinal conditions treated with IGS include fractures, metastasis, spinal slip disc and spinal curvature. Spinal imaging software allows surgeons to perform on the thoracic and lumbar regions of the spine, while many have pelvic trauma applications. Recently, there has been a push to develop more dedicated spinal IGS and robotic systems that would be better suited to strictly spinal or trauma surgeries.
Surgical robotics has tremendous potential to increase the effectiveness of existing procedures and to facilitate novel procedure types. The surgical robotics industry is, in many ways, still in its infancy, with more products in development than currently commercially available on the market. Early surgical robotics systems were based on industrial robots; however, most new surgical robotic systems are designed for highly specialized medical applications, which is a major drawback for most facilities.
Microscopically, the structure of hardened bone cement is similar to honeycomb, which gives it the ability to absorb loads under compression. Therefore, although it appears strong and hard, bone cement plays a role in dampening shock that is transmitted from the implant through to the bone. Typically, one package of bone cement contains 40 grams of bone cement material; this report considers one unit to be a 40 gram package of bone cement.