Abstract


To improve solid spinal fusion while avoiding the morbidity associated with autograft harvesting procedures, numerous alternatives have been investigated, including allograft, demineralized bone matrix (DBM), cell-based therapies and growth factors (i.e., bone morphogenetic proteins, platelet concentrates), and ceramic-based biomaterials. Even though all of these approaches have the potential to improve the outcome of spinal fusion procedures, most of them have not yet been validated by evidence-based clinical results, and thus they are not strongly advisable for clinical use, in addition to being particularly expensive. Here, we give an overview of the current clinical evidence for bone graft alternatives for spine surgery procedures. We will also evaluate the pros and cons of their use and briefly review the more relevant literature.

Abstract


Lumbar disc herniation is a common cause of back and radicular leg pain. A bulging annulus and contained herniated disc can compress a nearby exiting root as it enters the neuroforamen and may cause pain and neurological symptoms. Percutaneous laser disc decompression (PLDD) has been regarded as an effective alternative to microdiscectomy for the treatment of contained lumbar disc herniations. However, there is no consensus regarding the type of laser to use, the ideal wavelength, or the energy applied. The ideal laser irradiation should have a high water absorption coefficient and low tissue pervasion, to limit thermal injury. The 1470 nm wavelength of the diode laser is absorbed by water 40 times more effectively than the 980 nm wavelength. We conducted this study to evaluate the efficacy and safety of PLDD using a 1470 nm diode laser. We retrospectively reviewed the clinical data of 27 patients with radicular pain who underwent PLDD for the treatment of contained lumbar disc herniation during a 12-month period. The 1470 nm diode laser produces smaller local lesions, but greater tissue variations around the nucleus pulposus. This higher affinity for water lessens the formation of a carbonization zone, which results in less thermal injury of the adjacent nervous tissue.
According to the MacNab criteria, 85.2% of the cases were improved at 6-month follow-up. Pain decreased from VAS 8.1 preoperatively to VAS 3.1 postoperatively.
There is no consensus in the international literature regarding the ideal wavelength. Our results support the conclusion that PLDD using a 1470 nm diode laser is a safe and effective minimally invasive technique for patients with radicular pain affected by contained herniated lumbar discs.

Abstract


Purpose: This retrospective study was performed to evaluate the safety and efficacy of patient-specific 3D-printed guides (MySpine® Medacta, Switzerland) for pedicle screw placement in spine revision surgery.
Overview of the Literature: Placement of pedicle screws in spine revision surgery can be challenging due to the loss of anatomical landmarks and the presence of a fusion mass. Nevertheless, only a few papers have dealt with this topic. Several strategies, ranging from the freehand technique to navigation and robotics, have been developed. However, they all have drawbacks, including the amount of radiation given to the patient, the complexity of the equipment with a consequent increase in surgical time or costs, and the need of extended surgical training. Therefore, no consensus has yet been found regarding the best choice for dealing with revisions. Recently, patient-specific 3D-printed guides for screw placement have been introduced. Prospective studies have demonstrated their superiority over the freehand technique in primary deformity cases, but there are no studies on their results in revisions.
Methods: Patients who underwent revision surgery for adult spinal deformities with 3D-printed guides were included. Radiographical parameters and complications were collected. The accuracy of each screw was measured on postoperative CT scan and graded according to the Gertzbein-Robbins and Zdichavsky classifications.
Results: Nine patients (mean age 34.6 years, mean follow-up 34.4 months) were included for a total of 203 screws. The relative accuracy (Gertzbein-Robbins A+B) was 94.7%. Of the 11 misplaced screws, 8 (72.7%) were lateral, 3 (27.3%) were anterior and 0 were medial. No perioperative complications were recorded, and no screw needed revision.
Conclusions: The present technology appears to be effective and safe for pedicle screw placement in spine revision surgery and does not require the costs, training and radiation exposure associated with navigation and robotics.