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Multilevel laminectomy without fusion was traditionally used to effect multilevel neuro­logic decompression, but was complicated by high rates of postoperative kyphosis and is not routinely recommended today [1, 2]. Multilevel laminectomy with fusion minimizes the risk of postoperative kyphosis; however, it does so at the expense of cervical motion, requires more stringent postoperative restrictions, has higher implant costs, has greater risk of complica­tions, and may be associated with the potential for accelerated adjacent segment degeneration (ASD).

Laminoplasty is a posterior method for spinal cord decompression that was originally devel­oped as an alternative to multilevel laminectomy

drift posteriorly [4]. Laminoplasty affords several advantages over laminectomy alone. First of all, laminoplasty has a much lower rate of post­operative kyphosis and thus potentially less neck pain, deformity, or recurrent myelopathy. Laminoplasty also avoids the development of a post- laminectomy membrane, which can cause recurrent cord compression. Additionally, the preservation of bone stock and covering over the dura can make a revision posterior operation safer and easier to perform than after multilevel laminectomies. Laminoplasty is also a motion­sparing approach that has the advantage of avoiding potential fusion-related complications (e.g., nonunion, implant failure, potential for accelerated ASD), and patients can also be more aggressively rehabilitated in the early postopera­tive phase.

However, patients undergoing skip laminec­tomy did have a shorter operative time and less blood loss. Most of the studies included in the systematic review did not demonstrate a signifi­cant difference in the complication rates between the two techniques. The same systematic review did highlight the fact that almost all of the pub­lished studies have had small sample sizes, were not randomized, and had a high risk of bias.

Proper patient positioning is critical for facilitat­ing a successful surgery and avoiding potential complications. Mayfield tongs are typically used to immobilize the cervical spine and also prevent any pressure on the eyes and face. The patient is then positioned prone onto longitudinal bolsters on the operative table in order to diminish abdom­inal pressure, and care is taken to pad the knees and lower legs. The foot of the operative bed is then flexed up, which bends the knees and pre­vents the patient from sliding caudally as the table is placed into a reverse Trendelenburg posi­tion in order to decrease venous pressure at the surgical site. Next, the shoulders are gently pulled caudally and taped in this position to both keep them out of the way for lateral x-ray localization and also to reduce redundant skinfolds along the back of the neck. It is important to not tape the shoulders with excessive force, as this may lead to a brachial plexus neurapraxia. The neck is then placed into a neutral to slightly flexed alignment. Avoiding neck extension during positioning is important for a couple of reasons. First, neck extension generally results in further narrowing of the canal diameter and thus can worsen spinal cord compression. Second, neck extension results in more overlap and shingling between adjacent laminae, making the operation more difficult to perform. Typically, once the neck position is properly set during positioning, it does not need to be changed during the laminoplasty procedure. However, if one is performing a fusion in con­junction with laminoplasty, it will be important to reposition the neck into an appropriate amount of lordosis prior to securing the instrumentation.

neck extension more than what the patient could tolerate preoperatively. This may necessitate using a video laryngoscope (e.g., GlideScope) or even a fiber-optic intubation in patients who can­not tolerate much neck extension without devel­oping neurologic symptoms or who have difficult airways. Furthermore, it is important to maintain adequate spinal cord perfusion intraoperatively, being especially mindful during anesthetic induc­tion and when raising the head to place the patient in a reverse Trendelenburg position. There is no consensus on the optimal intraoperative blood pressure, but keeping the mean arterial pressure (MAP) above 80 mmHg is a good guideline. Those patients with significant preoperative hypertension may require a higher MAP goal throughout the surgery. An arterial line can be necessary for those with labile blood pressure or when cuff readings are not reliable.

Of note, it is often necessary to focus the burr­ing along the cephalad aspect of each lamina as this is the area that tends to be both thicker and potentially covered by the overhang, or “shin­gling”, of the caudal aspect of the superior lam­ina. Paradoxically, burring in this cephalad region requires extra caution because, whereas the dura is protected by the ligamentum flavum along the inferior portion of the lamina, there is no protec­tive flavum along the cephalad aspect of the lam­ina. As the lamina is thinned, it becomes somewhat translucent, and one can appreciate the yellowish hue of the underlying ligamentum along the caudal aspect of the lamina and, along the cephalad aspect, the bluish hue of the under­lying dura or the crimson of the longitudinal epi­dural veins. Once this color change is seen, the bone is sufficiently thin enough to be removed with a curette or small Kerrison rongeur. As the lamina is being thinned, a Penfield 4 or angled micro-curette can also be used to periodically palpate whether the lamina has been completely divided or not.

According to Matsumoto et al., premature laminoplasty closure occurs in up to 34% of seg­ments with suture fixation, and bone struts can dislodge into the spinal canal causing neurologic compression [

Foraminotomies can be done where necessary. However, there is no conclusive evidence on whether prophylactic C4/C5 foraminotomy

Occasionally, lateral mass fusion is per­formed in conjunction with laminoplasty. The benefit of “laminoplasty and fusion” versus “laminectomy and fusion” is that the former provides a larger surface area for bony fusion. However, this is at the expense of using the laminae for local autograft. Additionally, the sequence of instrumentation needs to be appro­priately orchestrated because lateral mass screws need to be inserted prior to opening the laminoplasty. In general, we prefer laminec­tomy and fusion over laminoplasty and fusion for the reasons above.

each of the operative levels (Fig. 11.1b). A hole is then burred through the spinous process

11.1c) so that it can be secured to the opened

completing the bilateral exposure to allow the creation of the opening and hinge troughs as dis­cussed earlier in this chapter. Just prior to creat­ing the troughs, the hemi-laminae on the opening side are decorticated with a burr (Fig. 11.2a). Once both troughs are made and the laminoplasty opened, a hole is burred through the ipsilateral hemi-lamina at each level (Fig. 11.2b). The pre­viously osteotomized spinous process, with its preserved muscular attachments, is now secured to the surface of the decorticated hemi-laminae to keep the laminoplasty open (Fig. 11.2c). This is accomplished by passing titanium cables through the drill holes in the spinous process and its cor­responding hemi-lamina (Fig. 11.2c). A sche­matic of the final construct is seen in Fig. 11.2d.

Finally, the paraspinal muscles on the opening side are sutured back to the spinous processes and the wound is closed.

As with any posterior cervical procedure, a lay­ered closure of the muscle, fascia, subcutaneous, and skin layers is important. After a deep drain is placed, the cervical extensor muscles are first reapproximated with Vicryl sutures. This is fol­lowed by figure-of-eight stitches to securely close the fascial layer in a watertight fashion. With each interrupted figure-of-eight suture, the fascia is reattached to the underlying muscle. It is important that this fascial layer be accurately identified, especially since it may be retracted lat­erally by the end of the case when the wound is being closed. The subcutaneous and skin layers are then closed in separate layers and the incision covered with a sterile dressing.

Since the goal of laminoplasty is to preserve motion, we do not typically put patients in a