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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.
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