Imageology study of correlation loss and its related factors after short-segment pedicle screw reduction and fixation for lumbar fractures / 中国骨伤

OBJECTIVE@#To analyze the correction loss after posterior segmental fixation for lumbar spine fractures and explore the related image factors.@*METHODS@#Posterior short-segment fixation was received in 48 patients with L@*RESULTS@#The average follow-up was 12 to 18 (16.13±5.39) months. LKA, AVH and VWA at 1 week postoperative and those at the final follow up, were significantly improved compared with those preoperative (@*CONCLUSION@#The angle of adjacent intervertebral discs and anterior height of injured vertebrae were lost statistically after posterior short-segment pedicle screw treatment for lumbar fractures, and multivariate analysis showed that all of them were correlated with load-sharing score.

The Relationship between Superior Disc-Endplate Complex Injury and Correction Loss in Young Adult Patients with Thoracolumbar Stable Burst Fracture

BACKGROUND: To determine the relationship between superior disc-endplate complex injury and correction loss after surgery in a group of young adult patients with a stable thoracolumbar burst fracture. METHODS: The study group was comprised of young adult patients who had undergone short-segment posterior fixation and bone grafting under the diagnosis of a stable thoracolumbar burst fracture from March 2008 to February 2014. Follow-up was available for more than 1 year. Before surgery, magnetic resonance imaging was performed to determine injury to the anterior longitudinal ligament, posterior longitudinal ligament, and superior and inferior intervertebral discs and endplates. Correction loss was evaluated by the Cobb angle, intervertebral disc height, upper intervertebral disc angle, vertebral wedge angle, and vertebral body height. RESULTS: No significant relation was noted between correction loss and an injury to the anterior longitudinal ligament, posterior longitudinal ligament, inferior intervertebral disc/endplate, and fracture site, whereas an injury to the superior endplate alone and superior disc-endplate complex showed a significant association. Specifically, a superior intervertebral disc-endplate complex injury showed statistically significant relation to postoperative changes in Cobb angle (p = 0.026) and vertebral wedge angle (p = 0.047). CONCLUSIONS: A superior intervertebral disc-endplate complex injury may have an influence on the prognosis after short-segment fixation in young adult patients with a stable thoracolumbar burst fracture.

Radiological Outcome of Short Segment Posterior Instrumentation and Fusion for Thoracolumbar Burst Fractures

STUDY DESIGN: Retrospective study. PURPOSE: To evaluate the radiological outcome of the surgical treatment of thoracolumbar burst fractures by using short segment posterior instrumentation (SSPI) and fusion. OVERVIEW OF LITERATURE: The optimal surgical treatment of thoracolumbar burst fractures remains a matter of debate. SSPI is one of a number of possible choices, yet some studies have revealed high rates of poor radiological outcome for this SSPI. METHODS: Patients treated using the short segment instrumentation and fusion technique at the Spinal Injuries Center (Iizuka, Fukuoka, Japan) from January 1, 2006 to July 31, 2012 were selected for this study. Radiographic parameters such as local sagittal angle, regional sagittal angle, disc angle, anterior or posterior height of the vertebral body at admission, postoperation and final observation were collected for radiological outcome evaluation. RESULTS: There were 31 patients who met the inclusion criteria with a mean follow-up duration of 22.7 months (range, 12-48 months). The mean age of this group was 47.9 years (range, 15-77 years). The mean local sagittal angles at the time of admission, post-operation and final observation were 13.1degrees, 7.8degrees and 14.8degrees, respectively. There were 71% good cases and 29% poor cases based on our criteria for the radiological outcome evaluation. The correction loss has a strong correlation with the load sharing classification score (Spearman rho=0.64, p<0.001). CONCLUSIONS: The loss of kyphotic correction following the surgical treatment of thoracolumbar burst fracture by short segment instrumentation is common and has a close correlation with the degree of comminution of the vertebral body. Patients with high load sharing scores are more susceptible to correction loss and postoperative kyphotic deformity than those with low scores.

Interspinous H-shaped bone grafting and bilateral facet interbody fusion for prevention of delayed kyphosis after surgical treatment of thoracolumbar fracture / 中华创伤杂志

Objective To evaluate the clinical effect of interspinous H-shaped bone grafting and bilateral facet interbody fusion in treatment of thoracolumbar fracture with severe disc injury and posterior ligamentous complex (PLC) injury after posterior pedicle screw fixation and its role in prevention of delayed kyphosis.Methods The study involved 19 cases of thoracolumbar fractures with severe disc injury and PLC injury,including 11 males and 8 females,at age of 23-59 years (mean 43.8 years.All cases were treated with posterior pedicle screw fixation (including 11 cases treated with unilateral laminectomy decompression) and C-arm X-ray showed favorable fracture reduction.For prevention of postoperative delayed kyphosis,the interspinous H-shaped bone grafting plus bilateral facet interbody fusion by using the iliac autografts was done.Neurologic recovery was assayed by using Frankel scale and lumbar and iliac pain by visual analogue scale (VAS).Cobb angle was detected as well.Results All cases were followed up for 24-64 months.At final follow-up,all cases showed neurological improvement for at least 1 to 2 Frankel grades except for two cases with Frankel Grade A,with mean Cobb angle of (2.0 ± 3.7) ° (range,-4.9°-8.1 °),mean VAS of lower back pain of (1.1 ± 1.2) points (range,0-4 points) and insignificant angle loss or kyphosis.The thin layer CT scan indicated complete integration of the transplanted bone grafts,with no complications like implant loosening or breakage.Conclusion Interspinous H-shaped bone grafting and bilateral facet interbody fusion is a good choice for prevention of delayed kyphosis after posterior pedicle screw fixation of thoracolumbar fracture with severe disc injury and PLC injury.

Radiologic Analysis of Postoperative Sagittal Plane Correction in Lumbar Degenerative Kyphosis (LDK) / 대한척추외과학회지

STUDY DESIGN: This is a retrospective study OBJECTIVES: We radiologically analyzed the correction of the sagittal imbalance and the proximal fusion level to prevent correction loss and the usefulness of iliac screws in LDK. SUMMARY OF THE LITERATURE REVIEW: Complications can be encountered during fixation and fusion as most of the LDK patients are aged, and the osteoporosis that causes fixation loss is known to affect the loss of correction. MATERIALS AND METHODS: We analyzed the cause of correction loss among 35 patients who underwent surgery and who were followed up for at least 1 year. All the patients had performed gait analysis before operation. The operative techniques were pedicle subtraction osteotomy and fixation to S1. For analyzing causes of correction loss, we analyzed the degrees of lumbar lordosis for the sagittal correction and the degrees of the preoperative thoracolumbar kyphosis for the proximal fusion range. For analyzing the usefulness of iliac screws, the subjects were divided into two groups: 1) the -iliac screw (23cases) group for the patients who were fixed without iliac screws and 2) the +iliac screw (12cases) group for the patients who were fixed with iliac screws. RESULTS: There were no patients who had marked anterior pelvic tilt. It is important to correct the lumbar lordosis over 20degrees compared with the preoperative thoracic kyphosis. There are 10 cases of preoperative thoracolumbar kyphosis > or = 10degrees and 25 cases of preoperative thoracolumbar kyphosis or = 10degrees, 4 cases that were fixed to T10 had no sagittal correction loss, and 2 of the 6 cases that were fixed to T11 or T12 had sagittal correction loss. For the 25 cases of preoperative thoracolumbar kyphosis < 10degrees, 5 cases that were fixed to T10 had no sagittal correction loss and 1 of the 20 cases that were fixed to T11 or T12 had sagittal correction loss (p<0.05). 6 cases (26%) in the -iliac screw group (23 cases total) and 1 case (8%) in the +iliac screw (12 cases total) showed sagittal correction loss (p<0.05). CONCLUSIONS: It is important to make the postoperative lumbar lordosis over 20degrees compared with the preoperative thoracic kyphosis for correcting sagittal imbalance, to decide on the proximal fixation level according to the preoperative thoracolumbar kyphosis and to fix with iliac screws.

Analysis for Etiology of Correction Loss after Surgical Treatment of Osteoporotic Vertebral Fracture with Neurologic Deficits / 대한척추외과학회지

STUDY DESIGN: A retrospective radiologic study of 23 cases OBJECTIVES: This study evaluated the etiology of correction loss after surgical treatment of osteoporotic vertebral fractures with neurologic deficits SUMMARY OF LITERATURE REVIEW: osteoporotic vertebral fractures with neurologic deficits were treated with anterior decompression with posterior instrumentation or an Egg shell operation. MATERIALS AND METHODS: We experienced 23 cases treated surgically for osteoporotic vertebral fracture with neurologic deficits. In group A (16 cases), anterior decompression with posterior instrumentation were performed, with group B (7 cases) receiving an Egg shell operation. The kyphotic angle using Cobb's method and endplate injury were evaluated preoperatively, postoperatively, and at last follow up. Group A was subdivided into A1 and A2 according to preoperative and postoperative kyphotic angle, as well as being divided by endplate injury into subgroup a and b. Overcorrection of preoperative kyphotic angles were performed in A1, and undercorrection in A2 group, with endplate injury in subgroup a. RESULTS: Postoperative correction was 13.4 degrees+/-3.4degrees and correction loss was 9.68degrees+/-8.05degrees in group A, and 21.5degrees+/-5.0degrees and 8.0degrees+/-1.73degrees in group B, respectively. Correction loss of group A1 (13.4degrees +/-8.8degrees ) was significantly larger than A2 (4.71degrees +/-3.14degrees ) (p=0.011). The correction loss of group A1a (18.0degrees +/-9.3degrees ) was significantly larger than group A2 (8.5degrees +/-3.1degrees ) (p=0.050) and A2a (p=0.036). The correction loss of group A1b was significantly larger than group A2b (p=0.029), and correction losses were not significantly different in A2a (6.0degrees +/-4.0degrees ) and A2b (3.25degrees +/-1.7degrees ) (p=0.289). CONCLUSIONS: Less Correction loss was found in the undercorrection and non-endplate injury group

Analysis of Correction Loss after Pedicle Subtraction Osteotomy in Patients with Sagittal Imbalance: Radiologic Aspects / 대한정형외과학회잡지

PURPOSE: To validate the surgical principles by analyzing the cause of a correction loss after pedicle subtraction osteotomy in patients with a sagittal imbalance in the radiological aspects, retrospectively. MATERIALS AND METHODS: Forty cases were analyzed radiographycally according to the presence (Group A) or absence (Group B) of the lower mobile segment and anterior column support performed (Group A2) or not (Group A1), respectively. RESULTS: The overall correction loss of the total fused part appeared to increase in group A (p=0.025) and the degree of lordosis of the osteotomy site showed an almost zero correction loss in group A and B. No statistic difference of the correction loss of the upper segment of the osteotomy site between the two groups was found (p=0.138). The correction loss of the lower segment of osteotomy site increased statistically more in goup A (p=0.014). The correction loss in group A occurred more in the lower segment than in the upper segment and the correction loss of the lower segment in group A1 appeared to have a better correlation than group A2 (p=0.012). CONCLUSION: Correction loss occurs at the intervertebral disc of the mobile segment. It is considered desirable to have anterior column support to all lower segment of the osteotomy site, because the correction loss increases more in the lower segment than in the upper segment.

Long term clinical outcome of the hook-screw combined instrumentation in preventing correction loss after surgical treatment of unstable thoracolumbar fractures / 中华创伤杂志

Objective To evaluate the biomechanical basis and long term clinical outcome of the offset hook-screw combined instrumentation in preventing against correction loss after it is used to treat the unstable thoracolumbar fractures. Methods Of 98 cases treated with the offset hook-screw combined instrumentation from July 1997 to December 2002, 64 with follow-up over two years were reviewed. All 64 cases received operation within average 3.2 days after injury, of which 41 were fixated with CD or CD-Horizon instrumentation and 23 with TSRH instrumentation. The long term clinical outcome evaluation included the maintenance of the vertebral height restoration, the sagittal kyphotic Cobb angle loss and the coronal Cobb angle correction loss. Results No death occurred. But after operation, there was one case with worsened neurological deficits (recovered one week after surgery) and two with deep infection. The average post-operative vertebral height and the coronal Cobb angle were restored by 89.0% and 100.0% respectively and the sagittal kyphotic Cobb angle corrected from preoperative 31?to postoperative -1? . During the follow-up for 24-62 months, no instrumentation breakage occurred. The pseudoarthrosis was affirmed in one case and suspected in two with the vertebral height loss of 8.6% and the kyphotic Cobb angle correction loss of 4?respectively. Conclusions The offset hook-screw combined instrumentation can satisfactorily restore the normal sagittal profile, effectively prevent the fixation loosening or breakage, minimize the mechanical failure of instrumentation, and particularly reduce the loss of long-term correction.