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Chapter 16: Dorsal Cervical Decompression (Laminectomy/Hemilaminectomy and Laminotomy) 155

laminectomy itself provides minimal to no decompressive effect for creating some confusion. It is more properly termed a foraminotomy
most lesions, and effective decompression of the spinal cord and/or and facetectomy. The approach was initially described by Lipsitz
nerve roots is usually predicated on removal of the offending mass and Bailey, later modified by Rossmeisl and coworkers, and further
lesion itself. modified by Schmied, Golini and Steffen [12–15]. It is referred to in
Wound closure begins with ensuring hemostasis within and this book as the lateral cervical approach and is discussed in greater
around the exposed vertebral canal, and continuing to control detail in Chapter 18.
bleeding or oozing in muscle layers as the wound is closed from
deep to superficial. Hematoma and seroma formation can lead to
secondary spinal cord compression [10]. There is ongoing contro- Dorsal Approach to the Occipital–Atlantoaxial
versy as to whether an interpositional material such as fat or cellu- Vertebral Canal (Medulla Oblongata to C2)
lose sponge (e.g., Gelfoam®) should be placed over the dural tube in Lesions involving the cranial‐most aspect of the vertebral canal
an effort to prevent laminectomy scar formation that might also may require some alteration to the positioning and approach uti-
result in secondary spinal cord compression, and specifically which lized. Greater flexion of the head-neck junction may be indicated
material is best [11]. to increase the distance between the cranial aspect of the C2
The muscle and fascial layers are apposed sequentially using spinous process and the dorsal arch of C1, to which it is attached by
absorbable suture material. The subcutaneous and skin closures are the dorsal atlantoaxial ligament. For lateralized lesions within the
routine. If postsurgical MRI or CT is contemplated, sutures rather C1 or C2 vertebral canals a hemilaminectomy may suffice, and is
than metallic staples are used in the skin. Drains are not routinely preferable to a standard dorsal laminectomy that would compro-
placed but are an option if excessive dead space and/or oozing exist mise or sacrifice the spinous process of C2, the dorsal atlantoaxial
and concern the surgeon. Closed suction drains are much preferred ligament, or the ligamentum nuchae, any of which could predis-
over open passive drains. Neck bandaging is not routinely employed pose to loss of function, instability, and possible vertebral luxation.
but may be chosen at the discretion of the surgeon. For large lesions at C1–C2 that would not be adequately visualized
or manipulated via a limited hemilaminectomy approach, and
Hemilaminectomy (C3–T1) where more dorsal exposure was desired, an alternative to lami-
The approach and dissection to the vertebral column are identical nectomy would be laminotomy of the axis [16]. In this technique,
to that described in the preceding section. Depending on the type, a high‐speed burr and bone‐cutting forceps are used to create a
size, and location of the lesion as provided by preoperative imaging hinged osteotomy of the dorsal arch of C2, starting from the cra-
studies, the spinous process might be preserved or included in the nial 75% of the C2 spinous process, that can be rotated dorsally and
bone removal. Similarly, the degree of articular facet removal is bal- cranially on the preserved attachment of the cranial aspect of the
anced between increased exposure and the desire to avoid vertebral C2 spinous process to the dorsal arch of C1 (Figure 16.8).
artery trauma/hemorrhage and loss of stability. Combined as needed with hemilaminectomy of C1 lateral to the
attachment of the dorsal atlantoaxial ligament, this approach can
Lateral Approach to the Cervical Vertebral Column provide good access for removal of lesions (frequently intradural/
(C3–T1) extramedullary meningiomas that appear to have a predilection
In addition to traditional laminectomy/hemilaminectomy proce- for this site), and repair of the lamina preserves the major stabiliz-
dures and their shared patient positioning and muscular dissec- ing soft tissue structures. As needed, C1–C2 hemilaminectomy or
tions, an alternative approach has been advocated. Unfortunately, it C2 laminotomy plus C1 hemilaminectomy can be further extended
has also been described in the literature as a “hemilaminectomy,” through the caudal occiput for exposure of lesions extending

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Figure 16.8 Laminotomy of C2. The dorsal
atlantoaxial ligament is left intact. A high‐
speed pneumatic drill and small round burr
are used to make lateral cuts in the verte-
bral arch (left). The vertebral artery and its Vertebral artery
radicular branches are more easily avoided
with the laminotomy than with standard Dorsal atlantoaxial ligament
hemilaminectomy. A caudal transverse
osteotomy is made with large bone‐cutting
forceps (right). Placement of the bone cut-
ters is aided by scoring the bone with the
burr. Source: Fingeroth and Smeak [16].
Reproduced with permission of John Wiley
& Sons, Inc.