Anterior Body Height Loss Research Articles

NEUROLOGICAL OUTCOME IN ASSOCIATION WITH COLUMN RESTORATION AND CONSOLIDATION OF UNSTABLE THORACIC AND LUMBAR SPINE FRACTURES — ASSESSMENT BY CLINICAL EXAMINATION AND IMAGE STUDIES

A total of 116 surgically treated patients with unstable fractures of the thoracic and lumbar spines were subjected to this study on basis of the simple radiographic and CT findings of the injured spinal column and neurological changes at the injured cord and/or roots level. Among them 50 patients were paraplegics and 66 patients were non-paraplegics. Spine fracture patterns shown on axial CT images were classified into five types on the basis of the fracture severity of vertebral body associating the canal compromise by the encroached fracture fragments from middle column and posterior element. Type I: vertical linear fracture through mid-anterior and posterior elements; Type II: retropulsed fragment in the canal with intact posterior element; Type III: retropulsed fragment in the canal with fracture of the posterior element; Type IV: severe comminution of body and disruption of posterior element around the canal; Type V: fracture-dislocation of comminuted vertebral body and neural arch (with or without double margin sign and with or without vacant facet sign). Displacement of vertebral body on lateral plane radiograms showed significant difference ([Formula: see text] < 0.001) between the non-paralytics and paralytics, but there were no differences in kyphotic angles and anterior body height loss between the two groups. Neurological injury was highly complicated in cases of the fracture-dislocation (20 out of 22 patients: 90.9%). Unstable fracture which occurred in the thoracic level showed high incidence of neurological injuries [24 out of 28 patients (85.7%)]; complete paralysis in 20 (71.4%) out of 28 patients in comparison with that of the thoracolumbar and lumbar fractures. Anteroposterior (AP) diameter of the compromised neural canal and percentile surface area of the compromised canal showed significant differences between the paralytics and non-paralytics (canal diameter: [Formula: see text] < 0.05, canal compromise: [Formula: see text] < 0.05). Neural deficit was highly complicated in type IV and V fractures. In conclusion, it was found that clinical neurological assessment and CT-based fracture classification were the valid approaches in managing the fractured spine.

The effect of post-operative immobilization on short-segment fixation without bone grafting for unstable fractures of thoracolumbar spine

Background:Controversy regarding the fixation level for the management of unstable thoracolumbar spine fractures exists. Often poor results are reported with short-segment fixation. The present study is undertaken to compare the effect of fixation level and variable duration of postoperative immobilization on the outcome of unstable thoracolumbar burst fractures treated by posterior stabilization without bone grafting.Patients and Methods:A randomized, prospective, and consecutive series was conducted at a tertiary level medical center. Thirty-six neurologically intact (Frankel type E) thoracolumbar burst fracture patients admitted at our institute between February 2003 and December 2005 were randomly divided into three groups. Group I (n = 15) and II (n = 11) patients were treated by short-segment fixation, while Group III (n = 10) patients were treated by long-segment fixation. In Group I ambulation was delayed to 10th-14th postoperative day, while group II and III patients were mobilized on third postoperative day. Anterior body height loss (ABHL) percentage and increase in kyphosis as measured by Cobb's angle were calculated preoperatively, postoperatively, and at follow-up. Denis Pain Scale and Work Scales were obtained during follow-up.Results:Mean follow-up was 13.7 months (range 3-27 months). At the final follow-up the mean ABHL was 4.73% in group I compared with 16.2% in group II and 6.20% in group III. The mean Cobb's angle loss was 1.8° in group I compared with 5.91° in group II and 2.3° in group III. The ABHL difference between groups I and II was significant (P = 0.0002), while between groups I and III was not significant (P = 0.49).Conclusion:The short-segment fixation with amenable delayed ambulation is a valid option for the management of thoracolumbar burst fractures, as radiological results are comparable to that of long-segment fixation with the advantage of preserving maximum number of motion segments.

Posterior instrumentation with transpedicular calcium sulphate graft for thoracolumbar burst fracture

From October 2005 to September 2006, 20 patients with an acute thoracolumbar burst fracture underwent posterior instrumentation with transpedicular intracorporeal calcium sulphate grafting. The mean age of the patients at surgery was 41.8 years; 14 were men and six were women. The mean follow-up period was 28.5 months. Pre-operative computed tomography showed that the mean canal compromise was 53.5%. The Cobb angle was improved from 21.70 to 2.40 degrees, and the final loss of correction was 4.60 degrees. The anterior body height was corrected from 50.3% to 86.6%, and the average loss of anterior body height was 7.7% at final follow-up. All six patients with partial neurological deficit initially had improvement. According to the Denis criteria, the average pain score was 1.8, and the final mean work score was 2.5. Only one case had implant failure. Analysis of the results indicated that this technique can restore and maintain sagittal alignment and anterior body height, providing satisfactory short-term clinical results.

Preliminary study on a single balloon cross-midline expansion via unipedicular approach in kyphoplasty

Recently, bilateral transpedicular kyphoplasty with a single balloon was performed for osteoporotic vertebral body compression fractures (OVCFs) to reduce the fees of the operation, but the time of operation and radiation exposure are longer. The aim of this study was to determine the safety and effectiveness of a single balloon cross-midline expansion via unipedicular approach in kyphoplasty for OVCFs. Thirty-six patients with painful OVCFs (61 vertebrae) were enrolled in this research. Unilateral transpedicular puncture was performed under the fluoroscopy monitoring of an oblique angle down the pedicle. A single balloon was introduced through unipedicular approach. The final balloon position was in the midline of the vertebral body with the balloon cross-midline expansion and bone cement filled. Clinical outcomes were determined by comparison of the preoperative and postoperative visual analogue scale (VAS) and Oswestry disability index (ODI). Radiographic assessment included restoration of vertebral height and correction of kyphosis. Follow-up was conducted for 6 - 12 months (mean 9.2 months). Thirty-six consecutive patients with 61 vertebrae were successfully operated on with a mean operation time of 37.4 minutes per vertebra. All patients had dramatic pain relief and functional recovery within 96 hours after the procedure with no surgery or device-related complications. VAS score improved from 7.27 +/- 1.02 preoperatively to 2.71 +/- 0.75 postoperatively (P < 0.01). ODI score was decreased from (71.14 +/- 10.94)% preoperatively to (26.56 +/- 6.35)% postoperatively. The average loss of anterior body height was (14.33 +/- 2.76) mm before procedure and (10.03 +/- 1.83) mm after procedure (P < 0.01), while the average loss of middle body height was (10.15 +/- 2.70) mm before procedure and (5.89 +/- 1.83) mm after procedure (P < 0.01). The kyphotic deformity was corrected from (23.43 +/- 5.00) degree to (16.16 +/- 2.77) degree (P < 0.01). The pain relief and functional recovery were substantial and maintained to the last follow-up without any re-collapse or adjacent level fracture. A single-balloon cross-midline expansion via unipedicular approach in kyphoplasty for OVCFs is an effective and safe procedure with less cost, less operation time and less radiation exposure when compared with the conventional kyphoplasty technique.

The preliminary study on a single balloon cross-medline expansion using unipedicular approach in kyphoplasty

Objective To evaluate the clinical efficacy and safety of kyphoplasty with single balloon cross-midline expansion using unipedicular approach for osteoporotic vertebral body compressive fracture (OVCF).Methods Thirty six cases of painful OVCF were included in the study,with 61 vertebrae involved.Under X-ray fluoroscopy monitoring,kyphoplasty was performed using a unilateral,single,balloon via a unilateral transpedicular approach.A final balloon position was in the midline of the vertebral body with the balloon cross-midline expansions and bone cement filled. Clinical outcomes were determined by comparison of preoperative and postoperative VAS and ODI scores.Radiographic assessment included vertebral height restoration and correction of kyphosis.Follow-up was conducted for 6.0-12.0 months(mean 9.2 months).Results Thirty-six consecutive patients with 61 vertebrae were successfully operated with an operative time of(37.4±9.6)rain per vertebra.All patients had significant pain relief and functional recovery within 96 h after the procedure with no surgery-and device-related complications.VAS score improved from(7.3±1.0)preoperatively to(2.7±0.8)postoperatively(t=19.53,P＜0.01).ODI score was decreased from(71.1±10.9)%preoperatively to(26.6±6.4)%postoperatively(t=18.54,P＜0.01).The average anterior body height loss was(14.3±2.8)mm before procedure and(10.0±1.8)mm after procedure(t=14.68,P＜0.01).The average middle body height loss was(10.2±2.7)mm before procedure and(5.9±1.8)mm after procedure(t=16.44,P＜0.01).The Cobb's angle was corrected from 23.4°±5.0° to 16.2°±2.8°(t=15.60,P＜0.01).Some leakages of cement around the anterior margin of vertebra and inter-vertebral space were found in 2 patients,but there were no clinical symptoms.X-ray examination indicated there were no cement leakages in other vertebra.The pain relief and functional recovery were substantial and maintained to the last follow up without any re-collapse or adjacent level fracture.Conclusions A single-balloon cross-midline expansion using unipedicular approach in kyphoplasty for OVCF is effective and safety,less operation time,less radiation exposure compared to the conventional kyphoplasty technique. Key words: Radiology,interventional; Osteoporosis; Fractures,compression; Spinal fractures

Decision of Posterior Fixation Level by Load-Sharing Classification in Thoracolumbar and Lumbar Burst Fracture

Study Design : Retrospective study on 54 thoracolumbar and lumbar burst fractures treated with pedicle screw instrumentation. Objectives : To decide the optimal level of fusion in thoracolumbar and lumbar burst fractures treated with pedicle screw instrumentation by load sharing concept. Summary of Literature Review : Short segment pedicle screw fixation is condemned with frequent failure in maintenance of reduction. The type of posterior fixation construct that is most desirable is less well defined. Materials and Methods : Using the Load-Sharing classification, Group I consisted of 24 cases with fractures totaling 6 points or less underwent surgery which was subdivided into two subgroups(A : 1 level above and below including fractured vertebra, B : long segment fixation). Group II consisted of 30 cases with fractures totaling 7 points or more underwent surgery which was subdivided into three subgroups(C : 1 level above and below including fractured vertebra, D : 2 levels above, 1 level below including fractured vertebra, E : 2 levels above and below the fractured vertebra). Change of segmental kyphosis, inter-screw angle, upper disc height, lower disc height and anterior body height were measured using post-operative and follow-up lateral radiographs. Results : Comparing two subgroups in group I(A Vs. B), group A showed definitely more loss of upper disc height than group B but the others were not significantly different. Comparing three subgroups in group II(C, D, E), group C showed definitely more loss of reduction than two other groups but loss of anterior body height was not significantly different. There were no significant differences between group D and E. C o n c l u s i o n s : For fracture totaling 6 points or less, the long segment fixation(2 level above and 1 level below including fractured vertebra) is a successful method at thoracolumbar junction and short segment fixation to preserve motion segment at lumbar spine. For fracture totaling 7 points or more, short segment fixation is inappropriate and long segment pedicle screw fixation (2 level above and 1 level below including fractured vertebra) could effectively treat burst fractures of thoracolumbar and lumbar spine.

Transpedicular Instrumentation and Short-Segment Fusion of Thoracolumbar Fractures: A Prospective Study Using a Single Instrumentation System

Eleven patients were prospectively treated with bilateral short-segment transpedicular instrumentation using the Posterior Segment Fixator (Ace Medical Co., Los Angeles, CA, U.S.A.) construct combined with posterolateral fusion using autogenous iliac crest bone graft for the treatment of thoracolumbar vertebral fractures. All patients were evaluated clinically, radiographically, and functionally for a minimum of 2 years (mean 33 months). Four of the 11 patients (36.3%) had breakage or disengagement of the caudad screws during this interval. During the follow-up period, the angle of kyphosis increased an average of 12.9 degrees. The loss of correction was greater in those patients in whom the instrumentation failed (22 degrees) than in those patients in whom it did not (7.7 degrees). Five of the patients (45.5%) had a progressive increase in the angle of kyphosis of 10 degrees or more. At follow-up, the average loss of anterior vertebral body height for all 11 patients was 14% when compared with the body height that had been attained at surgery. Six of these patients (54.5%) had 10% or more loss of anterior body height. Despite the high incidence of failure of the instrumentation, progressive increase in the angle of kyphosis, and progressive loss of anterior vertebral body height, there was no worsening in the patients' Frankel grade postoperatively. The high rate of hardware failure and major postoperative loss of fracture reduction associated with this construct suggest that posterior short-segment pedicle-screw instrumentation with the Posterior Segment Fixator was not adequate to ensure stabilization of thoracolumbar fractures in this small group of patients. Maintenance of postoperative fracture reduction was the most consistent predictor of satisfactory functional outcome.