10 Cervical and Posterior Arch Augmentation
Summary
Cervical vertebroplasty is performed far less often than thoracic and lumbar vertebroplasty but is an important treatment for patients with fractures and neoplastic involvement of the cervical spine. Osseous augmentation of the cervical spine has greater technical challenges due to the surrounding neurovascular structures and the small size of the vertebral bodies and should be performed by experienced practitioners. Cervical vertebroplasty is typically performed under fluoroscopic or CT guidance with various approaches utilized such as the transoral, translateral, and transpedicular approaches. Posterior arch osseous augmentation can be performed for neoplastic and non-neoplastic pathologies located in the pedicles, laminae, and in the spinous process. Injection of cement into the pedicles or laminae must be done with care as important nerves and vessels are located directly adjacent to these osseous structures and CT guidance can be very useful when augmenting the posterior arch. Spinoplasty can be very useful prior to placement of interspinous spacers to augment the strength of the spinous process in patients at high risk of fracture or osseous erosion around the spacer.
10.1 Cervical Augmentation
10.1.1 Introduction
Percutaneous vertebroplasty is widely considered an effective procedure in the treatment of selected patients with vertebral compression fractures (VCFs) related to osteoporotic disease, primary and secondary osteolytic tumors, and some cases of trauma. 1 The majority of vertebroplasty procedures are performed in the thoracic and lumbar spine by fluoroscopic or computed tomography (CT) guidance, where established radiological landmarks and approaches to the body allow safe and rapid augmentation. VCFs also occur in the cervical spine, in around 1% of patients affected by primary or secondary spinal neoplasms. 2 , 3 For these cases, cervical vertebroplasty presents an alternative or an adjunct treatment to radiotherapy (RT) or cervical spinal surgery in reducing pain and improving stability of the VCF. However, compared with thoracolumbar vertebroplasty, augmentation in the cervical spine presents technical challenges due to the small size of target vertebral bodies, the difficulty in visualizing bony landmarks, and the surrounding neurovascular and airway structures. Cervical vertebroplasty thus requires special considerations in regard to the procedural approach, sedation, and radiological guidance, and should be performed by experienced operators. 4
Operative surgery of the cervical spine remains essential when the spinal canal is compromised and/or when there is spinal instability. 5 , 6 Even when cervical lesions generate instability, anterior fixation of the spine may not be well tolerated, particularly in patients with short life expectancy, immune compromise, or significant debilitation. Moreover, even in patients with longer life expectancy and greater baseline functional status, surgical treatment carries risk of restricted cervical movement, which may not be desirable for younger patients.
Palliative RT has demonstrated powerful effects in the treatment of secondary cervical lesions that require pain relief and vertebral bone remineralization. 7 It does not require general anesthesia, and can be performed in patients who are in extremely poor clinical condition. However, post radiation remineralization generally occurs in 3 to 6 months after treatment, with interval risk of vertebral collapse or radiation-specific complications such as radiation-induced myelitis or soft-tissue radionecrosis. 8
10.1.2 Historical Perspective
The first vertebral augmentation procedure reported in the literature was performed in the cervical spine by Galibert et al, who performed vertebroplasty to treat an aggressive C2 hemangioma. 9 The procedure provided rapid, almost complete pain relief for the patient, leading to an increased uptake of the procedure and application to treat thoracolumbar fractures. It is currently considered highly effective for cervical lesions and can be considered the best treatment option after stringent patient selection, even in extremely aggressive osteolytic lesions (▶Fig. 10.1a, b).
10.1.3 Image Guidance
Conventional vertebroplasty can be safely performed under either fluoroscopic or CT guidance; the choice of either method is at the discretion of the practitioner. In cervical vertebroplasty, both fluoroscopy and CT can be used if necessary along with multiplanar reconstructions. Prior to the procedure, comprehensive radiological analysis is advisable, including both CT and magnetic resonance imaging (MRI), with cervical vessel imaging with CT or MR angiography. Careful pre-procedural planning reduces the likelihood of complications.
10.1.4 Procedural Approaches
Transoral
The transoral approach (utilized by Galibert et al in the first cervical vertebroplasty procedures) is considered the preferred approach in the case of a lesion involving the upper cervical spine (C1–C4). 10 – 12 In this approach, the patient is positioned supine, with mild hyperextension of the neck and an oropharyngeal retractor utilized to achieve sufficient mouth opening. The needle is introduced directly through the oral cavity along the midline, traversing the oropharynx to reach the vertebral body directly (▶Fig. 10.2a). In certain cases, even the clivus can be reached through this method, allowing the treatment of large osteolytic lesions of the skull base. 13
Benefits
In contrast to alternative approaches, the transoral method avoids almost all the main neurovascular cervical structures, as thin pharyngeal muscles, fascia, and anterior ligaments are the only structures that will be perforated by a correctly placed transoral needle. 14 This approach is a known neurosurgical route for treating intradural and extradural diseases and, despite not being a percutaneous approach, it remains one of the safest ways to reach the upper cervical vertebrae.
Limitations
General anesthesia and intubation are mandatory for the transoral approach. Oral intubation is possible but generally not recommended, as oral cavity should not be occupied by tools other than the vertebroplasty equipment; this allows more freedom when mediolateral or craniocaudal inclination of the needle is preferred, depending on the location of the disease. Nasotracheal intubation is thus accomplished, and may be performed with fiberoptic assistance. Infection is a key source of potential complication in the transoral approach, with wound infections occurring in less than 2% and meningitis in less than 5%. 15 , 16 For this reason, perioperative and postoperative antibiotic prophylaxis is recommended for preventing infection, as preparation of the posterior oropharynx with iodine is not always sufficient to obtain 100% oral cavity sterility.
Translateral
Translateral approaches (TLAs; ▶Fig. 10.2c) have been described for cervical lesions at C1 to C5, and allow direct percutaneous treatment of the vertebral body. Three translateral methods are differentiated: the anterolateral approach (ALA), the TLA, and the posterolateral approach (PLA). In the ALA, 17 , 18 with moderate hyperextension of the head, the carotid is manually compressed and pushed laterally by the operator’s fingers. The needle is carefully introduced under the mandibular angle, between the trachea and the carotid–jugular axis. 17 , 18 The TLA for vertebral augmentation has usually been described in the literature as a combined fluoroscopy-CT guided treatment. In some cases, this approach may be somewhat difficult to perform due to the risk of damaging nearby neurovascular structures. 17 The PLA 19 , 20 may be performed in certain cases: the needle is placed posterolaterally through the posterior cervical space, bypassing the main lateral neurovascular structures. 19 , 20 However, in the case of anatomical variations or tumoral mass displacement (▶Fig. 10.3), the vertebral artery may prevent the PLA from being utilized. 21
Benefits
In some cases, translateral procedures can be performed under simple local anesthesia. Nevertheless, considering the difficult anatomical area to be accessed, sedation of the patient is strongly advised. Moreover, since these procedures utilize a fully percutaneous approach, there is no significant risk of infection, and a simple skin disinfection is considered sufficient for infection prevention. A TLA is typically the optimal choice in case of obese or short-necked patients. 22
Related posts:
4 Physical Examination Findings in Patients with Vertebral Compression Fractures
13 Radiation Exposure and Protection: A Conversation Beyond the Inverse Square Law, Thermoluminescent Dosimeters, and Lead Aprons
14 Appropriateness Criteria for Vertebral Augmentation
18 Predisposing Factors to Vertebral Fractures
23 Number of Levels Appropriately Treated with Vertebral Augmentation
30 Vertebral Augmentation in Instrumented Spinal Fusions
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
