Istituti Clinici Bergamaschi, Italy
Marco Bortoluzzi is the National Coordinator of the Section of Spine Surgery of the Italian Society of Neurosurgery.Member of the Technical Committee on spinal implants - Section V Health Council;Coordinator of the National Protocol on Inter Specialistico Prophylaxis in Spine surgery and guidelines in treatment of Spondylodiscitis.He carried out his professional career at universities and hospital of eminent national and international institutes.He worked as academic teaching at the University of Brescia in the Degree in Medicine and Surgery in the Course of Human Physiology for the teaching of Physiology of the Nervous System stand-alone; in the School of Specialization in Neurosurgery, Sports Medicine, and Psychiatry; in the course of Diploma in Nursing Science and Physiotherapy. He is author of 156 scientific publications. He has performed as more than 8,000 surgeries in all areas of the cranial and spinal neurosurgical pathology. He was speaker, moderator, discussant in over 120 conferences and national and international scientific symposiums.He is the reviewer of leading international scientific journals. He is a member of: • Italian Society of Neurosurgery • Italian Society of Neurology, Neurosurgery and Neuroradiology Hospital • Italian Society of Cranial Base • Italian Society of Neurosonology.
Background. In recent years, there has been expanding interest in the use of arthroplasty as an alternative to anterior cervical discectomy and fusion. Nevertheless, the scientific literature does not show clear evidence in the real benefit and effectiveness of anterior cervical discectomy with arthroplasty (ACDA) compared to anterior cervical discectomy with fusion (ACDF). On the other hand ACDF seems to be burdened by a high percentage of adjacent segment disease (AS), ranging from 25% to 92% (Baba et al., 1993; Hilibrand et al., 1999; Goffin et al., 2004) within 10 years. D Objectives. To investigate the clinical long term results of ACDF, with special attention to the incidence of ASD, the restoring of segmental and regional lordosis after segmental fusion and the relation between cervical alignment and neck pain. Study Design. A retrospective clinical and radiographic study. Method. 80 patients’ submitted to anterior microdiscectomy and Carbon Cage (Brantigan®) replacement, filled with bank bone at one single level in cervical degenerative disease were investigated. 47 were males and 33 females. Age ranged from 22 to 77 years with mean age 47 years. Follow up from 12 to 19 years (Jan. 1996 to Jan. 2014). For comparison, a group of 40 patients with interbody cervical fusion at two adjacent levels with Brantigan cages (from Jan. 2004 to Jan. 2010) was also examined. Clinical symptoms. Pure radicular symptoms in 66 patients (82.5%); combined myelo-radiculopathy - “mild” medullary symptoms (every days tasks normally performed without discomfort) in 14 patients (17.5%). Surgical target. Correction of the segmental deformity (kyphotic or straight segment) with restoration of disc height and segmental lordosis; obtain a solid fusion preventing further malalignment. Recreate the conditions for a “compensate cervical spine”, restoring the posterior preload status and the guiding function of the posterior facets. Surgical details. Progressive gentle distraction of the vertebral bodies up to 5-7 mm and mobilization of the facet joints with the Kaspar distractor. Gently insertion in the interbody space of a 7° carbon cage filled with bank bone. Cartilagineous bone removed only with curettes to have feelings that subcondral bone is carefully preserved. This is the key condition to prevent the cage’s subsidence and obtain the segmental lordosis. No drill, no interbody distractor, no anterior plate. Surgical transient complications. Dysphagia (47.5%-resolution within 3-9 days), mild hoarseness (6% -resolution within 5 days), 1 case of vocal paresis, resolved within 4 weeks. All complications resolved without additional neurological deficit or other complications. Clinical Results. All radicular clinical symptoms resolved (66 cases -100%). Significant improvement in (57%) with “mild” medullary symptoms (14 cases). In the remaining, six cases (43%) no clear improvement but no discomfort in daily activities. All patients returned to preoperatory activities and declared a high satisfaction for the results obtained. Anatomical segmental results. In all cases correction of the preoperatory segmental deformity, restoration of disc height, solid fusion (within 3 years), no subsidence or dislodgment, restoration of the segmental lordosis (significant in 58%, less in 42%). Biomechanical results. No Junction Syndrome, no patient has been re operated at the same or at adjacent levels. (Follow up up from 12 to 19 years). A significant finding has been observed: the correction of a single level promotes in 61% (49 cases) a spontaneous improvement of the regional cervical lordosis “a self-recovering process”. This process is depending on the “cervical spine age”. Is favored by the spine lordotic profile, high discs, elastic proprieties of posteriori ligaments, absence of vertebral body deformations and is disadvantaged by spine kyphotic profile, facet arthritis, low disc height, adjacent discs dysfunction, kyphotic deformation of vertebral bodies, loss of elastic properties of posterior ligaments. Post-operative Neck pain, evaluated with Odom’s criteria, was observed in 21 cases (26%) with a significant difference: 16% in the group with spontaneous improvement of regional lordosis (8/49 cases) and 42% in the group without regional lordosis (13/31cases). This finding suggests that neck pain is a symptom of a perturbation of the cervical balance in which the abnormal alignment is due to dysfunction of discs, facets and ligaments. Discussion. The most significant data of our investigation is the absence of the junction syndrome or reoperation at the same or adjacent segment. The crucial biomechanical target in order to restore a more effective cervical balance and avoid an adjacent disease is the restoration of the segmental lordosis. In all our cases this target has been achieved, reversing the preoperatory segmental -straight or kyphotic- malalignment. Otherwise, the persistent malalignment promotes the degeneration of adjacent discs as well the pathologic changes in the kinematics and, in our experience, chronic neck pain in near 50% of cases. In papers reporting a high percentage of junction disease, the figures demonstrate that the resulting surgical treatment is a straight segmental fusions with a straight cervical spine, without correction of the preoperatory segmental deformity nor restoration of the segmental lordosis. In all these papers, the crucial biomechanical target to restore the segmental lordosis or a cervical balanced shape is never considered nor achieved. These constructs are biomechanically improper and favor the junctional syndrome. Moreover, this experience led us to believe to include in the surgical treatment not only the “neurological symptomatic” single disc but also the “centre/s of abnormal alignment”, not causing nervous compression but impeding the restore of a more balanced cervical lordosis. Particularly one, or more, degenerated adjacent discs, MRI detected, not causing nervous compression or disturb but impeding the restore of a balanced cervical lordosis or a kyphotic deformity of an adjacent vertebral body impeding the restore of a lordotic cervical spine. In this cohort of 40 patients with interbody cervical fusion at two adjacent levels with Brantigan cages, despite the preoperatory anatomical malignment, no subsidence or dislodgment of the cages has been observed ad in all cases a significant improvement of the Regional Cervical Lordosis has been achieved. While the neck pain is down to 7,5%. Conclusion. The target of surgical treatment is 1) resolve the clinical neurological symptoms and 2) improve the biomechanical setting of the cervical spine, reversing the straight or kyphotic malalignment. Loss of normal lordotic alignment induces pathologic changes in kinematics and accelerate degeneration of the adjacent segments. The adjacent disease is avoided by a proper biomechanical surgical strategy. The “biomechanical correction” of a single or more levels promotes in high percentage of cases “a self-recovering process” with a “spontaneous more harmonic” restoration of the regional cervical lordosis. The surgical treatment should consider not only the “neurological symptomatic” single disc but also the “centre/s of abnormal alignment”, not causing nervous compression but impeding the restore of a more balanced cervical lordosis. Anterior cervical discectomy with arthroplasty (ACDA) may be a promising alternative to ACDF in a select group of patients and only if it preserves or restores the segmental and regional cervical lordosis and improves the cervical balance.