Abstract


Due to the longer survival of cancer patients secondary to improved systemic treatments, there has been a recent increase in the incidence of spinal metastases. Metastatic disease involves the anterior vertebral body in 80% of cases. Progressive osseous invasion may result in pathologic vertebral fractures and neural structure compression. Surgical indications are spinal cord and cauda equina compression or spinal instability in patients with an expected survival of at least 6 months. Tumor resection and spine reconstruction in the lumbar region are technically demanding. Several approaches have recently been developed to access the lumbar spine: anterior lumbar approach (ALIF), lateral and extreme lateral transpsoas lumbar approach (LLIF, XLIF, DLIF), and oblique retroperitoneal lumbar pre-psoas approach (OLIF). Each technique has its advantages and drawbacks. OLIF is an emerging procedure that has progressively been used by spine surgeons. The retroperitoneal space allows direct access to the vertebra, thus avoiding injury to the paraspinal muscles, psoas muscle, and lumbar plexus. Between 2005 and 2017, 14 patients underwent somatectomy and spinal reconstruction using an oblique retroperitoneal lumbar pre-psoas approach at our institution. All were affected by lumbar vertebral metastases from solid and hematological tumors, and all presented a Tokuhashi score ≥ 12. L3 vertebral body was involved in 7 cases, L1 was involved in 3, L2 was involved in 2, and L4 was involved in 2. All patients underwent a lateral retroperitoneal approach to achieve vertebrectomy and spinal reconstruction with a cage. Spinal fixation was completed with pedicle screws and rods in 4 cases. No neurological worsening was noted except in one patient who presented a transitory deficit of the left ileopsoas muscle. The oblique retroperitoneal lumbar pre-psoas approach may be a valuable and feasible technique that is potentially able to significantly reduce tissue trauma in patients while still making it possible to achieve corpectomy and solid reconstruction of lumbar vertebral bodies. To our knowledge, this is the first reported series of patients with lumbar spinal metastases treated with the oblique retroperitoneal lumbar pre-psoas approach.

Abstract


Hemostasis plays a central role throughout neurosurgery. In microneurosurgery, a bloodless operating field under an operating microscope allows fast and effective surgery, thereby reducing the risk of postoperative hemorrhage. Apart from mechanical methods, such as positioning of the patient’s head and body, bone plugging, suction, and metal clips, neurosurgical hemostasis is achieved mainly with bipolar coagulation, which permits optimal control of hemorrhage, allows for fine coagulation of small vessels and is safe in patients with pacemakers and defibrillators. Gelatin sponge is a non-antigenic protein that can absorb 45 times its weight in blood, and, when wet, is plastered to the irregularities of the bleeding surface. It enables the repair of torn veins, such as the superior sagittal sinus, without compromising the patency of the vessel. Surgicel® (Johnson & Johnson, New Brunswick, NJ), the first oxidized cellulose to be introduced, is used to control capillary, venous, or smaller arterial bleeding because it acts as a matrix for the formation of a clot. Over the past few decades, research on the development of hemostatic agents has shifted to the use of fibrin sealants and flowable agents such as Tisseel Fibrin Sealant® (Baxter, Deerfield, IL), Evicel Fibrin Sealant® (Ethicon, Somerville, NJ) and FloSeal® (Baxter). Very recently, advanced hemostats with sealant properties similar to those of fibrin sealants have been introduced, such as Tachosil® (Baxter, Deerfield, IL) and Hemopatch Sealing Hemostat® (Baxter). Due to the different properties of these products it is important that we understand the efficacy of each hemostatic agent in different neurosurgical settings, such as in the control of parenchymal, subdural and epidural bleeding in both cranial and spinal surgery. The aim of this work was to review the principal technical aspects of hemostatic agents to optimize their use in different neurosurgical procedures.

Abstract


Introduction: Cervical laminectomy is a surgical technique that is used to decompress the spinal cord. The standard equipment for making bony cuts includes a high-speed drill (HSD) or osteotome; the ultrasonic BoneScalpel® (UBS) by Misonix (Farmingdale, NY) may be used for this purpose either alone or in combination with other instruments.
Objective: We describe the operative technique and principles behind the use of the Misonix BoneScalpelTM (MBS) for subaxial cervical laminectomy.
Methods: The features, functions and mechanism of the MBS are described. Use of a UBS for en bloc subaxial cervical laminectomy is outlined, including a description of the technique, the avoidance of complications, and perioperative considerations.
Results: Use of the MBS in cervical decompression is a safe and effective alternative to HSD when considering tissue selectivity, thermal control, and coagulative effects.
Conclusion: While the initial upfront cost of the MBS is greater than that of similar equipment, the potential long-term savings in time and resources can yield a cost-effective return. The MBS should be progressively incorporated into the surgical protocol as dictated by the surgeon’s comfort level.

Abstract


Introduction: Traumatic spinal injury presents the potential for significant morbidity and mortality, and posterior fixation and fusion with bone grafts is a primary treatment for many vertebral fractures. While iliac crest autograft (ICBG) is considered the gold standard in bone grafting, this carries risks of morbidity at the donor site as well as prolonging surgery time. Bone graft substitutes (BGS) may provide a viable alternative to autograft but there is little published data concerning its use in trauma. Therefore, we conducted this retrospective review to evaluate the outcomes for fusion among patients who have received a BGS during posterolateral fusion (PLF) for vertebral trauma.
Materials and Methods: This was a retrospective, consecutive patient cohort. Over a six-month period, we identified 27 patients who had undergone PLF for spine trauma and in whom a BGS comprised of bovine-derived apatite was used. All patients had followed the standard of care. The postoperative plain film radiographs at three, six, 12, and (optionally) 24 months were independently assessed by an orthopedic surgeon who was not affiliated with the hospital.
Results: We documented a radiographically observed fusion rate of 85% and a successful treatment rate of 92%. There were no adverse events related to the BGS. Patients who received a BGS with ICBG spent significantly longer in surgery than other patients. There were no adverse events related to the BGS.
Conclusions: The spondylodesis rate following surgery in which the BGS was used in PLF, whether alone, mixed with local bone, or mixed with ICBG is comparable to the rates that have been reported for iliac crest autograft in these indications. The data indicates that the BGS provides a useful adjunct in PLF for the treatment of traumatic spine vertebral injuries. The use of BGS also allows for shorter time in surgery, which may reduce resource utilization and thus lower the total costs of the procedure.
Clinical Relevance: Posterolateral fusion can be obtained with the use of a bio-derived BGS while reducing the time in surgery by avoiding the second procedure necessary to harvest ICBG. This may be advantageous in cases where the surgeon wishes to minimize operating time or when the availability of autograft is limited.