Acta Orthop. Belg., 2014, 80, 493-500 ORIGINAL STUDY The treatment of osteoporotic thoracolumbar severe burst fractures with short pedicle screw fixation and vertebroplasty Shaoqi HE, Lixing LIN, Xiaojun TANG, Yijiang HUANG, Minghai DAI, Maoxiu PENG, Guojing YANG, Chengxuan TANG From Department of Orthopaedic Surgery, Third affiliated Hospital of Wenzhou Medical School, Wenzhou, Zhejiang, China Objective : To investigate the clinical and radiological from preoperative 59.21 ± 26.63 to 19.74 ± 22.94 at results of short pedicle screw fixation and vertebro- final follow up (P < 0.001). The ODI scores were re- plasty in osteoporotic thoracolumbar severe burst duced from preoperative 81.68 ± 4.44 to 15.37 ± 5.54 fractures. at final follow up P( < 0.001). All 4 patients with par- Methods : From September 2006 to August 2010, 19 tial neurologica l deficit initially had improvement. consecutive patients sustained osteoporotic thoraco- Cement leakage was observed in 3 cases (two anterior lumbar severe burst fractures with or without neuro- to vertebral body and one into the disc without se- logic deficit and were included in this prospective quela). There were no instances of instrumentation study. All patients underwent short pedicle screw fix- failure and no patient had persistent postoperative ation and vertebroplasty. Segmental kyphosis, AVB- back pain. Hr and PVBHr, and Canal compromise were calcu- Conclusions : Vertebroplasty and short pedicle screw lated on radiographs pre-operatively, post-operative fixation has the advantages of both radiographic and and at final follow up. VAS, ODI and SF-36 were cal- functional results for treating osteoporotic thoraco- culated pre-operatively and at final follow up. lumbar severe burst fractures using a purely posteri- Results : Mean operative time was 70.8 min (range or approach. 60~100 min) and mean blood loss was 92 ml (range Keywords : spinal fracture ; pedicle screw ; short inter- 60~160 ml). The mean duration of their hospital stay nal fixation ; vertebroplasty. was 4.5 days (range 3-7 days). The operative incisions were healing well. Average follow up time was 40.1 months (range 24~72 months). The AVBHr was n Shaoqi He. n corrected from preoperative (48.1 ± 6.8) % to post- Lixing Lin. n Xiaojun Tang. operative (94.1 ± 1.7) % (P < 0.001). The PVBHr was n Yijiang Huang. corrected from preoperative (62.7 ± 4.8) % to post- n Minghai Dai. operative (92.8 ± 1.8) % (P < 0.001). Canal compro- n Maoxiu Peng. mise was corrected from preoperative (37.3 ± 5.8) % n Guojing Yang. to postoperative (5.9 ± 2.3) % (P < 0.001). The seg- n Chengxuan Tang. mental kyphosis was corrected from preoperative Department of Orthopaedic Surgery, Third affiliated Hospi- (20.6 ± 5.3) degree to postoperative (2.0 ± 3.2) degree tal of Wenzhou Medical School, Wenzhou, Zhejiang, China. (P < 0.001). VAS scores were reduced from preopera- Correspondence and phone calls about the paper should be directed to Tang Chengxuan at the following address, phone tive 7.21 ± 0.86 to 2.21 ± 0.98 at final follow up and fax number, and e-mail address : Department of Orthopae- (P < 0.001). SF-36 Bodily pain was reduced from pre- dic Surgery, Third affiliated Hospital of Wenzhou Medical operative 75.31 ± 13.85 to 13.74 ± 13.24 at final follow School, 108 WanSong Road, Ruian, Wenzhou, Zhejiang, Chi- up (P < 0.001), and SF-36 Role Physical was reduced na. E-mail : [email protected] © 2014, Acta Orthopædica Belgica. No benefits or funds were received in support of this study. The authors report no conflict of interests. Acta Orthopædica Belgica, Vol. 80 - 4 - 2014 he-tang-.indd 493 21/11/14 09:35 494 S. HE, L. LIN, X. TANG, Y. HUANG, M. DAI, M. PENG, G. YANG, C. TANG INTRODUCTION burst fracture Type A3 according to a comprehensive classification of thoracic and lumbar injuries (19) demon- Vertebral fractures usually become evident be- strated on both radiographs and computed tomography cause of pain which may affect a patient’s quality of (CT) scan. All the fractures were considered osteoporotic life, including back pain, functional limitations, de- according to T value of Bone density test less than -2.5. Polytraumatized patients, patients with preexisting spinal pression, disability, height loss caused by vertebral deformity (scoliosis, previous vertebral fracture in the (13,25) collapse and spinal instability . Osteoporosis area of interest), and patients with previous spinal opera- was the most common cause of vertebral fractures, tion were excluded. especially in women above 50 years old. Thoraco- There were 7 male and 12 female. The mechanism of lumbar burst fractures may be treated with anterior, injury was fall from a height in 6 patients, Slip in 6 pa- posterior, or combined of them. Consequently, ante- tients, road traffic accident in 5 patients and burden in the rior instrumentation with strut grafting, mesh cage remaining 2 patients. Non-serious associated injuries and plates have been introduced to augment the an- (distal radius fractures in three patients, Calcaneal frac- terior vertebral column and have proved to be effec- tures in two patients, and rib fractures in three patients), tive. However, an anterior approach is more inva- were recorded but they did not require additional surgery. sive and is associated with prolonged operation and Neurological assessment was made for each patient using hospitalization time, blood loss, donor site com- a rating system based on that of the American Spine In- jury Association (ASIA) impairment scale (2). Radio- plaints and increased morbidity, especially in osteo- graphic assessment was performed using anteroposterior porotic old patients. Short-segment pedicle screw and lateral roentgenograms, CT scan of the area of injury. instrumentation is a well described technique to re- Bone density test was performed using Dual-energy X- duce and stabilize thoracic and lumbar spine frac- ray absorptiometry and T value was record in each pa- tures (4,5). Osteoporoses, inadequate anterior col- tients. The vertebral kyphosis was measured from the umn support in osteoporotic thoracolumbar severe superior end-plate of the intact vertebra cephalad to the burst fractures results in poor fixation and thus is fracture to the inferior end-plate of the vertebra caudal to regarded as the potential causes of failure (18,9). the fracture. Anterior vertebral body height ratio (AVB- Many patients with acute burst fractures have re- Hr) was measured from the average of the anterior verte- cently undergone vertebroplasty to benefit from the bral body of the vertebrae above and below the fractured advantages of this procedure (18,9,30,1). Polymethyl- vertebra divided by the anterior vertebral body height of methacrylate (PMMA) vertebroplasty involves risk the fractured vertebra. Posterior vertebral body height ra- tio (PVBHr) was measured from the average of the pos- of cement leakage (11,27), whereas no other side- terior vertebral body of the vertebrae above and below effects have been adequately documented. the fractured vertebra divided by the posterior vertebral The hypothesis of this prospective clinical inves- body height of the fractured vertebra. Canal Compromise tigation in patients with osteoporotic thoracolumbar was determined using CT by directly measuring the an- burst severe fractures was that vertebroplasty with teroposterior canal dimension at the maximum area of PMMA supplemented with short segmental pedi- the retropulsed osseous fragment or fragments and was cle-screw fixation could sufficiently and permanent- reported in millimeters. This figure was then compared ly restore fractured vertebral body and reduce seg- with the average of similar dimensions measured at the mental kyphosis. levels above and below the injury level. The result of this comparison was reported as percent of anteroposterior MATERIALS AND METHODS canal compromise at the injury area. Back pain intensity was recorded on visual analog scale (VAS). Functional The clinical study proposal was approved by the med- outcome was measured using The Oswestry Disability ical ethical committee of the authors’ institution. From Index (ODI) (14) and the SF-36 domains Role Physical September 2006 to August 2010, 19 consecutive patients and Bodily pain (23). with an average age of 66.4 years, who sustained osteo- On admission, 4 (21%) of 19 patients had incomplete porotic thoracolumbar burst fractures with or without neurologic impairment. The time from injury to surgery neurologic deficit, were included in this study. All pa- varied from l d to 4 d (mean 2.7 d).19 patients located 2 tients were confirmed as a single recent thoracolumbar at T11, 5 at T12, 8 at L1 and 4 at L2.The mean preopera- Acta Orthopædica Belgica, Vol. 80 - 4 - 2014 he-tang-.indd 494 21/11/14 09:35 THE TREATMENT OF OSTEOPOROTIC THORACOLUMBAR SEVERE BURST FRACTURES 495 tive load-sharing classification of spine fractures was 7.1 The vigorous work and strenuous physical activity were (range 6~8) (21). The mean preoperative thoracolumbar restricted up to 8 weeks postoperatively. injury classification and scoring was 5.2 (range 4~8) (29). All patients were postoperatively followed clinically Based on the ASIA neurologic grading system, preopera- and radiographically at 2 days, three month, and one year tive neurological function was grade D in 4 cases and E around the time of rod removal and at every one-year in 15. All patients underwent short pedicle screw fixation interval thereafter. Patients were assessed for any neuro- and vertebroplasty within four days of admission, to logic complications. As for CT scan ; all patients had it reduce segmental kyphosis and restore vertebral body just after surgery and one year later. AVBHr, PVBHr and height. All patients received a calcium supplementation Segmental kyphosis were measured on the lateral radio- (1000 mg of elemental calcium daily) and vitamin D graphs. Canal Compromise was measured on CT scan. (400~600 UI of vitamin D).