CENTERPIECE plates with spinous process autografts, and resection of the C3, The Centerpiece Plate Fixation System (Medtronic Sofamor. Learn about cervical spinal fusion and a surgical technique known as anterior cervical fusion, also known as an anterior cervical discectomy and fusion (ACDF). Medtronic Sofamor Danek. CENTERPIECE T M Plate Fixation System. (k) Summary – K( May Submitter: Medtronic Sofamnor.
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Products Laminoplasty plates, suture anchors, and posterior cervical instrumentation with lateral mass screws and rod constructs are made by multiple manufacturers of orthopedic products, with similar design features. Category Laminoplasty plates, suture anchors, and posterior cervical spine instruments Device details Laminoplasty plates Laminoplasty hardware is available in cfnterpiece sizes for both lateral mass screws and plates.
Most plates are made of titanium or a titanium alloy. These anchors are the same ones used for many sports medicine procedures, such as arthroscopic shoulder labral repairs. Examples of suture anchors include Mitek GII suture anchors and the smaller 2-mm suture anchors, 3.
These have all been used and reported in the literature.
CENTERPIECE PLATE FIXATION SYSTEM. Surgical Technique
Examples of posterior cervical instrumentation with lateral mass screws and rod constructs include the DePuy Summit Fixation System medtroniic the Vertex Reconstruction system by Medtronic. It also has multiple screw-hole options for flexibility in screw placement.
Medtronic also offers the option of precut graft plates that have a central screw hole for fine adjustments of the plate on the allograft. Hinge plates to secure a displaced hinge are also available.
The bone screws are self-tapping and available in 2. The Blackstone NewBridge Laminoplasty Fixation system is similar, with 3 plate sizes that have teeth positioned on the lateral mass side of the plate to help maintain its position, as well as medtronkc tap for secure fixation on the lamina. An allograft strut completes the NewBridge system and is also preshaped; struts are available in sizes from mm. The screws for this system are 2.
The DePuy Mountaineer System comes in sizes from mm in 2-mm increments. Precontoured allograft struts are also an option with this cwnterpiece. Multiple other orthopedic companies make similar products. Suture anchors Suture anchors have a tapered body that helps reduce insertion torque. They come in various sizes to match various applications and bone qualities. Anchors of 2, 2. The suture that is secured to the anchor is made of nonabsorbable material that reduces the risk of knot breaking and resistance to fraying.
Posterior cervical instrumentation The posterior cervical instrumentation consists of 3. The rods are typically made of titanium alloy that can be cut and contoured as needed into anatomic lordosis. Prior to placement of the rods, the Mayfield attachment on the operating table can be adjusted as needed to optimize lordosis and sagittal alignment.
Placing all screws in line as much as possible aids placement of the rods see image below. The indications for this technique include congenital stenosis, ossification of the posterior longitudinal ligament, spinal cord tumors, and cervical spondylotic myelopathy CSM involving 3 or more disc levels. If performed for only 1- or 2-level disease, the limited length of decompression does not allow the free migration of spinal cord dorsally.
In addition, the laminoplasty plating systems have the ability to hold graft material in place which may help prevent re-closure centerplece the hinge. Posterior cervical instrumentation Posterior cervical instrumentation and fusion can be performed to treat pathology similar to that for which cervical laminoplasty is used, but with a broader scope.
Indications for instrumented posterior cervical fusion include stabilization following laminectomy performed for stenosis, tumor, abscess, or hematoma. Early efforts at posterior instrumentation centered on wiring techniques. However, significant failure rates were noted, particularly in patients with osteoporosis; additionally, removal of the posterior elements and scenarios where flexion forces need centerpjece be counteracted showed limited utility for wiring.
Regarding suture anchors, Yu et al reported on the use of Twinfix suture anchors and found no signs of loosening or pull-outs on postoperative follow-up radiography, and the Japanese Orthopaedic Association JOA score increased from an average of 8. The ideal candidate for this procedure meddtronic young with minimal degenerative changes and normal lordotic alignment. A review of the literature demonstrates excellent results with few complications.
Miyazaki et al reported that, at year follow-up postsurgery, neurologic status was maintained. Sekhon et al found that mm length x 3. Three patients experienced screw pullouts, none mrdtronic which required reoperation.
Postoperative CT scanning showed no compromise of the foramen transversarium or neural foramen. There were no cases of spinal cord or vertebral artery injury, infections or death, or adjacent segment disease at month follow-up. Comparison studies have demonstrated similar rates of neurological recovery.
Heller et al reported no statistical difference in outcomes between laminoplasty or laminectomy and fusion, but noted a twofold decrease in range of motion after laminectomy and fusion. Outside of these straightforward patient populations, further randomized studies are needed to compare superiority of these techniques.
Clinical Implementation Posterior cervical decompression implant choices Overview Cervical spondylotic myelopathy CSM is one of the most common spinal cord disorders in persons older than 60 years. Isolated radiating arm pain or numbness is consistent with nerve root dysfunction rather than spinal cord dysfunction, garnering the name radiculopathy. As some patients with CSM exhibit signs and symptoms of both radiculopathy and myelopathy, the term cervical myeloradiculopathy has been used to describe this syndrome.
A true myelopathic presentation from single-level disease can occur with herniation of a large central cervical disc; however, multilevel disease is far more common.
Multilevel cord compression results from cervical spondylotic stenosis, a degenerative process of the intervertebral discs, facet and uncovertebral joints, and the ligamentum flavum, separate from, or in conjunction with, congenital stenosis. The latter, known as postlaminectomy syndrome, is a feared complication that can exaggerate neurologic symptoms caused by continued impingement of the spinal cord.
Relevant anatomy The cervical spine is composed of 7 vertebrae in a lordotic alignment see image below. The C1 vertebra is termed the atlas, while the C2 vertebra is the axis; these two vertebrae have distinct anatomical features that differentiate them from the rest of the spine. The subaxial vertebral segments include C3-C7 and are similar to each other in morphology; they include anterior vertebral bodies connected to the posterior elements by pedicles bilaterally. Intervertebral discs are located between the vertebral bodies of C2-C7.
The posterior elements include lateral masses, laminae, and spinous processes. Note the lordotic alignment and facet joint orientation in the cervical spine as viewed from the lateral aspect. The superior process of the inferior vertebra lies anterior to the centerpeice process of the superior vertebra. The centeepiece processes are also seen where the vertebral artery runs in the transverse foramina, typically from C6 cephalad to C1. The 7 cervical vertebrae join each other medgronic through paired facet joints, which are created by the superior and inferior articulating processes of adjacent vertebrae.
The aforementioned lateral masses are important structures when contemplating posterior cervical instrumentation. Medrtonic anatomic borders of the lateral mass of each cervical vertebra are the medial and lateral aspects of the articulating processes and facet joint lines above and below see image below. In addition to its structural role in the axial skeleton, the kedtronic spine also houses the spinal cord within its spinal canal.
Anteriorly, the spinal canal is bounded by the vertebral bodies, the intervertebral discs, and the posterior longitudinal ligament. The lateral borders of the canal are created by the pedicles and the posterior borders by the ligamentum flavum and vertebral laminae see image below.
Paired vertebral arteries course through the cervical transverse foramina from C6 to C1; they subsequently pass posteriorly and superiorly over the dorsal aspect of the atlas to join the basilar artery at the brainstem.
The spinal cord is encased anteriorly by the vertebral body, laterally by the pedicles, and posteriorly by the two laminae. The nerve roots in the cervical spine branch from the spinal cord and travel anteroinferiorly before exiting the spinal canal via neuroforamina at the level of the intervertebral disc see image below. Clinical implementation overview Standard instruments are required for the dissection and retraction of the posterior spine elements.
A high-speed burr is needed for the laminoplasty. Several options are available to hold open the laminoplasty, including mini-plates, sutures, and suture anchors, as described below. The authors use somatosensory evoked potentials with preposition baselines obtained in individuals with severe stenosis or myelopathy. In addition, appropriate venous access is essential, and an arterial line is usually obtained for monitoring.
Arterial line monitoring is essential if the patient has myelopathy, as it is desirable to maintain higher than usual intraoperative mean arterial pressure.
In general, a mean arterial pressure around 85 mm Hg is a reasonable goal. The patient is then transferred prone onto a medtrnoic operating table with the appropriate padding. Two gel rolls can be used for the torso, and the legs are gently flexed with pillows.
The Mayfield attachment is adjusted to a near-neutral cervical alignment to optimize access to the posterior neck. The authors prefer to tuck the arms at the sides and tape down the shoulders to improve visualization with the intraoperative lateral radiograph.
Cervical Systems – Cervical Fusion | Medtronic
Gently taping the shoulders can also improve access to the posterior neck. Traction from the tape can cause a stretch injury to the brachial plexus; therefore, only gentle traction is applied. The bed is placed in a slight reverse Trendelenburg position to minimize venous engorgement and intraoperative venous bleeding see image below.
Technique After positioning the patient as described above, the cervical spine is prepared and draped in the standard fashion. The authors use impervious nonsterile plastic drapes to mark out a wide surgical field and prefer a chlorhexidine agent, if possible, for preparation. The authors outline and seal the margins of the surgical field with impervious iodine-impregnated strips see image below.
The skin incision can usually be localized by palpating the spinous processes of C2 and C7. The first palpable spinous process is usually C2.
The most prominent spinous process inferiorly is usually C7. Oftentimes, skin creases can be noted on the soft tissue shadows of the radiographs, and these can also help localize the dissection. A midline longitudinal incision is made sharply, and any skin bleeding is stopped with electrocautery. The remainder of the dissection is performed using electrocautery to minimize blood loss. It is important to meticulously control bleeding on posterior cervical approaches, centerpoece significant venous bleeding may be encountered.
CENTERPIECE PLATE FIXATION SYSTEM. Surgical Technique – PDF
The anatomical midline is a relatively avascular intermuscular plane; by remaining within this plane and avoiding dissection into the muscle, bleeding is minimized see image below. Staying in the midline will avoid unnecessary bleeding. Dissection is continued down onto the spinous processes of the desired levels, taking care to leave intact any soft tissue attachments or posterior ligaments above or below the surgical levels in order to avoid destabilizing adjacent segments.
To confirm the operative level at this point, an intraoperative lateral radiograph is obtained by placing a Kocher clamp onto a spinous process. Dissection is carried out to the junction of the lamina with the lateral mass, and the facet joints and capsules are preserved see image below. Caution is required to avoid penetrating between the lamina, especially if the neck is in a tucked position, as the amount of interlaminar space may vary.
Once the junction of the laminae with the lateral mass is identified bilaterally, the hinge can be placed at this level. The hinge is placed on the less symptomatic side to allow for better decompression of the more symptomatic side.
The ligamentum flavum is taken down at the proximal and distal ends of the laminoplasty but left intact throughout the other levels.