UNCOMPLICATED UNSTABLE SPINE INJURIES IN CHILDREN*

E.V. Ulrikh et al., 2013 UNCOMPLICATED UNSTABLE IN CHILDREN* E.V. Ulrikh 1, S.V. Vissarionov 2, A.Yu. Mushkin 2, 3 1 St. Petersburg State Pediatric Medical Academy, St. Petersburg, Russia 2 St. Petersburg Medical Academy of Postgraduate Studies, St. Petersburg, Russia 3 St. Petersburg Scientific Research Institute of Phthisiopulmonology, St. Petersburg, Russia Thirty four patients aged 3 17 years were operated on for uncomplicated unstable injuries of the spine. The surgery was performed within the next few hours or days after trauma in 15 cases and significantly later (in 2 6 months) in 19 cases. In the first group, the surgery included indirect posterior instrumental reduction and stabilization of the spine. In the second group, a two-stage surgery was performed simultaneously. The first stage included anterior decompression and stabilization, and the second posterior instrumentation. In both groups, the posterior fusion with bone autograft was performed. The post-operative follow-up was 5 years. The correction of deformity, spinal stabilization, and pain arrest were achieved in all cases. The surgical treatment of unstable uncomplicated spinal injuries in children must be conducted by emergency indications within the first hours and days after trauma. Key Words: spinal trauma, unstable spinal fracture, children, instrumental fixation. * Ulrikh EV, Vissarionov SV, Mushkin AYu. [Uncomplicated Unstable Spine Injuries in Children]. Hirurgia pozvonocnika. 2005;(2):8 12. In Russian. The increased incidence of household and transport injuries is inevitably accompanied by increased frequency of spine traumas. The transition from conservative to the earlier surgical methods for treating severe and concomitant spine injuries has significantly reduced their negative effects in adult patients. The development of tactic classification of spine injuries (AO/ASIF, F. Denis et al.) and advance in spine graft technologies [1, 3 5, 7] have significantly contributed to it. Decision making for a surgery on injured spine in a child is a much more complex issue. First, there is the preconceived opinion regarding high reparative properties of a pediatric skeleton. Second, pediatric traumatologists are conventionally more conservative: decision making for the necessity of spine surgery requires to break the psychological. Third (the key factor), there are no organizational structures (departments, crews) for carrying out emergency vertebrological aid to chil- 1

dren in our country. This study is based on the long-term experience of the authors on managing severe spine injuries in children. According to the statistical reports of St. Petersburg children s hospitals for 2000 2004, spine injuries constitute 5 7 % of the total number of injuries of the locomotor system; 15 25 children annually undergo surgical treatment. The conditions of megalopolis make it possible to provide qualified and specialized medical care for children with severe spine injuries. The relative availability of spinal instrumentation and possibility for prompt long-distance or face-to-face consultations with a pediatric spinal surgeon are favorable factors. The interest of medical administrative organs of the city is supposed to play a significant role in solving the emerging problems. Since 1998, we have recommended one to use the F. Denis spinal fractures classification in order to standardize diagnosing and determine the treatment tactics for children with spine injuries in St. Petersburg; undoubted advantages of this classification are its simplicity and practical orientation [6]. The absolute indications to emergency surgery neurological disorders in burst fractures and fracture-dislocations dictate the necessity for group decision-making for the type of tentative intervention by pediatric spinal specialists. These tactics allow one to replace the revision laminectomy in children (which is currently considered to have many adverse effects) with combined decompressive-stabilizing (in patients with burst fractures) or reconstructive-stabilizing laminoplasty including the revision of the spinal canal and spinal cord (in fracture-dislocations cases). It is significantly more difficult to make a decision for surgeries in children with dynamic mechanical and potential neurological spine instability. These injuries are attributed to the group of uncomplicated unstable ones. They include the following fractures: a) compression fractures with reduced height of the anterior vertebral segment by over 50 %; b) burst fractures of vertebral bodies without clinical symptoms of myelopathy; c) injuries of ligaments and the disc apparatus seat belt injury mechanism. In these cases, the decision whether or not to consult a spinal specialist depends on traumatologist s professionalism. The knowledge about dissatisfactory long-term results of conservative treatment of these injuries make one actively search for the more justified surgical methods. Material and Methods Thirty four children aged 3 17 years with uncomplicated unstable spine injuries were operated during the period from 1998 to 2004. The surgery was performed within the next few hours or days after trauma in 15 cases and significantly later (in 2 6 months) in 19 cases. Burst fractures were diagnosed in 32 patients; 2 children were operated on for seat-belt injuries. No severe compression spine fractures were observed during this period. Vertebral injuries at one and two levels were observed in 26 and 8 patients, respectively. Thoracic vertebrae were injured in 10 cases; lumbar vertebrae were damaged in 24 patients. The major causes of injuries included falls from a height and motor vehicle accidents, which resulted in flexion, flexion-rotation, and axial injuries of the spine. The diagnosis was confirmed by the X-ray spondylography in frontal and sagittal plan, CT studies (17 patients), and MRI (6 patients). In patients initially diagnosed as a compression vertebral fracture and operated in 2 6 months, the conventional preceding treatment was carried out, including longterm bed rest, a course of sanatorium rehabilitation treatment, and homeschooling. Chronic back pain and local kyphotic deformation were revealed in almost all patients by the time of vertebrologist examination. The scoliotic deformity of degree I II at the apex of fracture level was observed in 12 patients. 2

Spine instability was an indication for surgical treatment; its clinical signs already included progressive spinal deformity and chronic pain in the case of late admission. In the case of early hospital admission, the presence of threatening instability [2] (i.e., two and more spinal columns injured according to F. Denis classification) was considered to be a prognostically unfavorable factor. The period of time between the injury and the surgery had a significant effect on the choice of an intervention method. Posterior instrumental CD-fixation was performed in all cases; individual constructs were used during the first years, while serial products of different industries have recently been used. The technological differences in constructs do not considerably alter the principles and outcomes, although affecting the technique and duration of the surgery. Multi-support hook constructs were used in patients with injured thoracic vertebrae and transpedicular ones were used in patients with lumbar fractures. Thoracolumbar injuries were fixed using combined constructs with the lower transpedicular and upper hook supports (Fig. 1). In the cases when the surgery was performed from several hours to 7 10 days after the trauma, posterior indirect instrumental reposition (reclination) and spine stabilization were carried out in patients with burst fractures. Transpedicular fixation was performed within two adjacent functional spinal units (FSUs) in patients with fractures of a single vertebra in the lumbar spine. Patients with thoracic spine fractures were subjected to multi-support fixation with four hooks placed above and below the injured FSU. In patients with at least two fractured adjacent vertebrae, supporting elements were installed on the non-injured vertebra to ensure extensive fixation. Individual fixation of each zone was used in patients with multi-level injuries (traumas of at least two vertebrae localized at a distance of at least two FSUs from each other) (Fig. 2). a In the cases with seat-belt injuries, fixation of the injured FSU and resection of zygapophyseal joints to ensure better adaptation of the posterior bone structures during the reposition was performed. The surgery was finished by posterior local fusion by autobone graft and Redon drainage of the surgical wound for two days. Postoperative complications have been observed in none of the patients. The tactics of surgical intervention were completely different for patients who had been admitted late: formation of the rigid anterior fibrous block in the injury zone made it necessary to conduct interventions both in the anterior and posterior spine. This was achieved by simultaneous two-stage surgery. At the first stage, reconstruction of the anterior region was conducted through the thoracic, lumbotomy, or thoracodiaphragmal approaches (depending on the injury level), typically including disc epiphysisectomy, Urban wedge resection, and anterior fusion. At the second stage, Fig. 1 X-rays of a 14-year-old boy with the T11, L1 burst fracture: a before the surgery; b after posterior instrumentation b 3

metal constructs were installed through the posterior approach; the procedure was accompanied by deformity correction and spine stabilization. Finally, posterior fusion with autograft was carried out (Fig. 3). Results a b Fig. 2 X-rays of a 16-year-old boy with the burst fracture of L1, L4: a before the surgery; b after posterior indirect reposition and transpedicular fixation Fig. 3 a b Indirect instrumented reposition in patients operated during the next few hours or days after trauma made it possible to simultaneously recover the height of the injured vertebral body in most patients. The degree of correction achieved during the surgery was retained in the control roentgenograms recorded after one month and later. Steady pain arrest was on average observed two or three days after surgery; the patients were allowed to walk since the beginning of the second week, and were discharged for out-patient treatment after 14 18 days. In all cases, orthoses were additionally used since the transition to the vertical position (corsets of the Leningrad type were used initially, and functional reclination orthoses made of flexible materials have been currently used). One month after surgery, children were allowed to sit; remedial gymnastics without X-rays of a 15-year-old girl with the axial loading of the spine was prescribed. One year after surgery, burst fracture of L1: a before the vertical loadings were allowed and the corset was removed. Children were allowed to attend school 1.5 2 months after surgery. surgery, two months after the trauma; b after anterior reconstruction and posterior transpedicular six months to five years. The X-ray control was carried out immedi- The long-term results were followed up during the period from fixation ately prior to the discharge from the hospital, six months after surgery, and subsequently once a year. The clinical and X-ray results demonstrated stable fixation of the injured FSU. Among the patients who were operated on for the acute injury no loss of correction, destabilization, or fractures of instrumental 4

constructs have been observed during long-term follow-up period. In three children aged below 13 years with the incompletely corrected wedge-shaped deformity of vertebral body during growth within 1.5 2 years after the injury trauma an increase in the height of the injured vertebral body was detected. In seven cases, consolidation of the fractured vertebral body was observed within the same period at the level of achieved surgical correction. In two patients with injured lumbar vertebra, the formation of the spontaneous bone block due to ossification of the anterior longitudinal ligament was detected. The absence of consolidation of fractured fragments was noted in three patients with the initial loss of the height of vertebral body by over 70 80 %. This fact was the indication for performing the second stage of the surgery, discectomy (the resection of free-floating bone fragments) and conducting corporodesis using an autograft or a corundum ceramic graft, which was carried out not earlier than 6 months after the first stage of surgical treatment. Correction of kyphotic deformity was achieved in all patients with chronic injuries. In 17 cases, two-stage treatment had to be carried out immediately, which was connected with the existing strongly pronounced rigid deformation and the impossibility of reconstructing the normal anatomy of the spinal canal and the sagittal profile of the spine through the posterior approach only. Satisfactory results of posterior correction and fixation of the injured spine region were observed only in two patients. In all the cases, corporodesis was performed using autobone grafts. Children who had undergone two-stage operation were allowed to occupy vertical position 10 14 days after the surgery. In two cases, destabilization of the construct in patients with the solid anterior fusion bone block was observed six months after the intervention, which was the cause to excise it. We attributed this fact to the violation of the restrictive regime and the technical features of the constructs used at the early stages. No fractures of constructs were observed. None of the patients complained of back pain or limitations in spinal mobility during the long-term follow-up. Conclusions The results obtained attest to the reasonability of using the classification proposed by F. Denis to determine the type of spine injuries in children, with special attention paid to its tactical aspect. In patients with uncomplicated instable injuries receiving conservative treatment, the hope for the recovery of the shape of vertebral bodies and spine function is poorly justified. It should be acknowledged that the active surgical tactics commonly used for adult patients is preferred for children as well. We believe that surgical interventions in patients with severe uncomplicated spine injuries should be performed by emergency indications within the first hours or days after trauma. If a patient is in the state of shock, the surgery has to be performed within the first days after bringing him/her out of shock. The surgery can be postponed because of the presence of a concomitant life-threatening injury, but no longer than by 7 10 days after trauma. The anterior stabilization of the injured spine region was initially postponed in all the patients, since there was hope that the height of the anterior and middle columns of the compressed vertebra would increase during growth of a child. The surgical tactics has recently been revised. If there are indications for anterior stabilization (age of children over 13 years and higher degree of compression of the vertebral body that was not eliminated during the surgery), we deem it possible to perform the surgery as soon as 2 3 weeks after the posterior stabilization. 5

Early surgery during the acute period allows one to promptly arrest pain syndrome, to recover vertebral shape, to eliminate deformity of the spine canal and to stabilize spine using the minimal surgical intervention. The use of modern spinal instrumentation is the mandatory condition for achieving the result and for early activation of patients. In patients with late admission to hospital and with the developed clinical and radial signs of chronic spine instability, the surgery needs to be performed both for the anterior and posterior spinal columns. References 1. Voronovich IR, Peternko AM, Nikolaev VN. [Treatment of uncomplicated fractures in the thoracolumbar spine. In Prevention of Traumatism and Organization of Traumatological Aid in Oil and Gas Industry]. Moscow, 1983: 51 55. In Russian. 2. Dulaev AK, Shapovalov VM, Gaidar BV. [Closed Injuries in the Thoracic and Lumbar Spine]. St. Petersburg, 2000. In Russian. 3. Makarevich SV. [Variants of internal transpedicular fixation of the thoracic and lumbar spine]. Proceedings of the Congress of Russian traumatologists and orthopaedists with international participants, Yaroslavl, 1999:229 230. In Russian. 4. Rerikh VV, Ramikh EA, Strygin AV, et al. [Diagnosis and results of surgical treatment of compression penetrating fractures of thoracic and lumbar vertebral bodies]. Proceedings of the All-Russian Scientific and Practical Conference Problems of Spine and Spinal Cord Surgery Novosibirsk, 1996:47 48. In Russian. 5. Cotrel JM, Cotrel HB. Spinal Fusion. Science and Technique. N. Y., 1990. 6. Denis F. The three column spine and its significance in the classification of acute thoracolumbar spinal injuries. Spine. 1983;(8):817 831. 7. Edwards CC. Thoracolumbar trauma: Posterior reduction and fixation with a modular spinal system. Semin Spine Surg. 1990;(2):8 18. Corresponding author: Aleksandr Mushkin ul. Politechnicheskaja. 32, St. Petersburg, 194064, Russia, Pediatric surgery clinic, aymushkin@mail.ru Eduard Vladimirovich Ulrikh, MD, DMSc, Prof., St. Petersburg State Pediatric Medical Academy, St. Petersburg, Russia; Sergey Valentinivich Vissarionov, MD, DMSc, St. Petersburg Medical Academy of Postgraduate Studies, St. Petersburg, Russia; Aleksandr Yurevich Mushkin, MD, DMSc, Prof., St. Petersburg Medical Academy of Postgraduate Studies, St. Petersburg, Russia, St. Petersburg Research Institute of Phthysiopulmonology, St. Petersburg, Russia. 6