European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society
-
Cervical corpectomy is a frequently used technique for a wide variety of spinal disorders. The most commonly used approach is anterior, either with or without plating. The results for single-level corpectomy are better than in multilevel procedures. ⋯ Another benefit could be fewer hardware-related complications, higher fusion rate, larger range of instabilities to be treated by one implant system, less restrictive postoperative treatment and possibly better clinical outcome. From a biomechanical standpoint, in regard to primary stability the constrained systems, therefore, seem to be beneficial. Whether this leads to differences in clinical outcome has to be evaluated in clinical trials.
-
This work aimed to evaluate trunk muscle forces, internal loads and stability margin under some simulated standing postures, with and without external loads, using a nonlinear finite element model of the T1-S1 spine with realistic nonlinear load-displacement properties. A novel kinematics-based algorithm was applied that exploited a set of spinal sagittal rotations, initially calculated to minimize balancing moments, to solve the redundant active-passive system. The loads consisted of upper body gravity distributed along the spine with or without 200 N held in the hands, either in the front of the body or on the sides. ⋯ Co-activation in abdominal muscles (up to 3% maximum force) substantially increased extensor muscle forces, internal loads and stability margin, allowing a smaller critical muscle coefficient. A tradeoff existed between lower internal loads in passive tissues and higher stability margins, as both increased with greater muscle activation. The strength of the proposed model is in accounting for the synergy by simultaneous consideration of passive structure and muscle forces under applied postures and loads.
-
Spinal fusion in children with spina bifida: influence on ambulation level and functional abilities.
The aim of this study was to determine the influence of spinal fusion on ambulation and functional abilities in children with spina bifida for whom early mobilization was stimulated. Ten children (three males and seven females) with myelomeningocele were prospectively followed. Their mean age at operation was 9.3 years (standard deviation (SD): 2.4). ⋯ It takes about 12 months to recover to pre-surgery level, while small improvement is seen afterwards. After spinal fusion, ambulation often becomes difficult, especially in exercise walkers. These findings are important for health-care professionals, in order to inform and prepare the patients and their parents properly for a planned spinal fusion.
-
In this study we aimed to evaluate the role of closed-suction drainage on the extent of epidural fibrosis (EF) after lumbar disc surgery and to define a new grading system of epidural fibrosis in these patients, based on magnetic resonance imaging. Seventy-nine patients (34 women, 45 men) with a unilateral, single-level lumbar disc herniation were included in this study. ⋯ Pain intensity was evaluated by visual analog scale (VAS), and the patients' function and working ability were measured according to the Prolo functional-economic scale. We conclude that, in patients operated on for unilateral, single-level lumbar disc hernias, implantation of closed-suction drainage into the operation site results in less formation of EF radiologically and yields better clinical outcome.
-
Cervical spine fractures in patients with ankylosing spondylitis are serious and potentially lethal injuries with high complication rates. Treatment obstacles include long lever arms that generate large forces on any fixation device, osteoporosis, and, usually, kyphotic deformity. The Olerud Cervical Fixation System (OC), with cervical pedicle screws and rods, offers an opportunity to create a biomechanically stable posterior fixation in these complicated cases. ⋯ Extensive peroperative bleeding was encountered in two patients. One deep-wound infection was noted, postoperatively, and required surgical drainage, but no patients have been re-operated due to loosening of the instrument or to healing problems. In conclusion, the results of the present study indicate that the OC--and possibly other similar long-fixation systems that allow using both pedicle screws and lateral mass screws rigidly connected to a rod--is suited for treating subaxial cervical spine fractures in patients with ankylosing spondylitis, allowing high healing rates.