DOI: 10.33962/roneuro-2021-077 Outcome of patients undergoing posterior spine fixation and decompression for posttraumatic thoracolumbar spine fractures and the factors predicting it Geo Paul K. Jose, Tinu Ravi Abraham, P.K. Balakrishnan, Irphan Muhammed P.S., Haris T.P., Vala Parth Prakashbhai Romanian Neurosurgery (2021) XXXV (4): pp. 457-467 DOI: 10.33962/roneuro-2021-077 www.journals.lapub.co.uk/index.php/roneurosurgery Outcome of patients undergoing posterior spine fixation and decompression for posttraumatic thoracolumbar spine fractures and the factors predicting it Geo Paul K. Jose, Tinu Ravi Abraham, P.K. Balakrishnan, Irphan Muhammed P.S., Haris T.P., Vala Parth Prakashbhai Department of Neurosurgery, Government Medical College Kottayam, Kerala, INDIA ABSTRACT Background: Posterior spine fixation and decompression for thoracic and lumbar spine fractures have the advantage of stabilization of the fracture, decompression of neural canal, early mobilization and rehabilitation of the patient. The study aimed to find out the postoperative outcome and complications following posterior spine surgery and the factors affecting the outcome. Methods: A retrospective study was carried out among 44 patients who underwent posterior spine decompression and fusion for thoracic and lumbar spine fracture. The data regarding patient presenting symptoms, comorbidity, associated injuries and imaging finding in CT and MRI were collected. The postoperative outcome of patients after surgery was assessed using ASIA impairment scale, KPS, VAS scale for pain are noted at the preoperative and postoperative period. Other factors like improvement of bowel and bladder symptoms, back stiffness and return to the job after surgery were also found out. Results: There was a significant improvement in ASIA impairment scale (mean =0.74 grade), KPS score (mean = 40) and VAS pain scale (mean = 6.7) at 6 months follow up after surgery. Improvement in ASIA impairment scale was more in the patient with severe canal compromise (mean = 1.62 grade), patients with translational/ distraction injuries (mean= 1.01grade) and patients with paraparesis (mean=1.06). Only one- third of patients with bowel and bladder involvement improved after surgery. Around 56.8% of patients were able to return to jobs at 6 months follow up. Patients who were paraplegic at the initial presentation were mostly not able to return to jobs. The most common reported complication in the study was intraoperative pedicle breakage. Conclusion: Decompression of the spinal cord plus posterior spine fixation is a safe, reliable and effective method in the management of thoracic and lumbar fractures with significant improvement in outcome in terms of motor power, pain and quality of life. BACKGROUND Thoracic and lumbar spine fractures occurring as a result of trauma can lead to pain, neural compromise and deformity. The appropriate Keywords ASIA impairment scale, VAS, KPS, thoracolumbar spine fractures Corresponding author: Tinu Ravi Abraham Department of Neurosurgery, Government Medical College Kottayam, Kerala, India drtinu@gmail.com Copyright and usage. This is an Open Access article, distributed under the terms of the Creative Commons Attribution Non–Commercial No Derivatives License (https://creativecommons .org/licenses/by-nc-nd/4.0/) which permits non- commercial re-use, distribution, and reproduction in any medium, provided the original work is unaltered and is properly cited. The written permission of the Romanian Society of Neurosurgery must be obtained for commercial re-use or in order to create a derivative work. ISSN online 2344-4959 © Romanian Society of Neurosurgery First published October 2021 by London Academic Publishing www.lapub.co.uk http://www.lapub.co.uk/ 458 Geo Paul K. Jose, Tinu Ravi Abraham, P.K. Balakrishnan et al. treatment for these fractures ranges from conservative management with thoracic lumbar corset to surgical management with anterior/posterior instrumentation for fixation plus decompression1,2. Surgical management for these fractures has the advantage of stabilization of fracture with fixation, decompression of neural canal, early mobilization and rehabilitation of the patient3. Though there are both anterior and posterior approaches for thoraco- lumbar spine fractures most spine surgeons advocate posterior fusion and decompression as the treatment of choice for unstable fractures as the approach is less extensive1,4,5. Various posterior stabilization procedures are there which include hooks, wires, transpedicular screw and rod fixation, of which transpedicular screw and rod fixation is the preferred technique now6. In traumatic spine fractures the outcome following posterior spine decompression and fusion depends on various factors which includes timing of surgery, patient comorbidities, general condition of the patient, associated injuries. The outcome following the surgery is measured based on the extend of pain relief, to be able to mobilize the patient early, return to work, neurological recovery and development of any postoperative complications. This study was done to find out the factors affecting the post-operative outcome following posterior spine decompression and fusion surgery in patients with traumatic thoracolumbar spine fractures. The study also aimed to find out the postoperative outcome and complications following posterior spine surgery. METHODOLOGY A retrospective observational study was carried out among 44 patients admitted with thoracic and lumbar spine fracture who had underwent posterior spine decompression and fusion in the department of Neurosurgery, in a tertiary care center in central Kerala, India during the period from 1st January 2019 to 31st December 2020. Study involved collecting data regarding those patients who were admitted and operated for traumatic thoracic and lumbar spine fracture using the standard surgical protocol followed in the department. This involved laminectomy and decompression of the spinal cord +/- neural foraminal decompression and posterior spine fixation two levels above and below using polyaxial screws and rods. The data regarding presenting symptoms, comorbidities, associated injuries and imaging finding in CT and MRI was collected (like type of fracture, canal compromise and level of injury). Type of fractures were divided into posterior element only fractures, anterior wedge compression fracture, burst fracture and translation/ distraction injury. Canal compromise was divided into no/ mild (obliteration in CSF space is <50%), moderate (>/=50% obliteration in CSF space, but not deforming the cord), severe (compressing and deforming the cord). Level of injury was divided into upper dorsal(D1-D6), mid dorsal (D7-D9), dorso-lumbar junction (D10-L2) and lower lumbar(L3-L5). Other details like interval between trauma and surgery, and complications following surgery were also recorded. The post-operative outcome of patients after surgery was assessed using ASIA (American Spine Injury Association Scale) impairment scale (Table.1b), KPS (Karnofsky Performance Status) scale (Table.1a) and VAS (Visual Analog Scale) of pain (from 0-10), all of which were noted at the preoperative and post- operative (immediate,1 month and 6 months) periods from the data available in the department. Other factors like improvement in bowel and bladder symptoms, back stiffness and return to job after surgery were also found out. A) Karnofsky Performance Status Scale7 B) ASIA scale8 Score Findings Grade Findings 100 Normal no complaints; no evidence of disease. A (Complete) No Sensory or Motor Function is preserved 90 Able to carry on normal activity; minor signs or symptoms of disease. B (Sensory Incomplete) Sensory but not Motor Function is preserved below the neurological level and No Motor Function is preserved more than three levels below the Motor Level on either side of the body 80 Normal activity with effort; some signs or symptoms of disease. 70 Cares for self; unable to carry on normal activity or to do active work. 60 Requires occasional C (Motor Incomplete) Motor Function is preserved below the 459 Outcome of patients undergoing posterior spine fixation and decompression assistance, but is able to care for most of his personal needs. Neurological Level and More than half of key muscle functions below the Neurological Level of Injury have a muscle grade less than 3 (Grades 0-2) 50 Requires considerable assistance and frequent medical care. 40 Disabled; requires special care and assistance. 30 Severely disabled; hospital admission is indicated although death not imminent. D (Motor Incomplete) Motor function is preserved below the neurological level and At least half (half or more) of key muscle functions below the NLI have a muscle grade ≥ 3 20 Very sick; hospital admission necessary; active supportive treatment necessary. 10 Moribund; fatal processes progressing rapidly. E (Normal) If sensation and motor function as tested are graded as normal in all segments 0 Dead Table 1. showing a) Karnofsky Performance Score b) ASIA Impairment Scale7,8 In the end of the study the post-operative clinical, radiological and functional outcome in patients undergoing thoraco-lumbar posterior spine fixation and decompression was determined. The factors affecting post-operative outcome in patients undergoing thoraco-lumbar posterior spine fixation and decompression were also determined. The common complications following thoraco-lumbar spine fixation and decompression were also found out. Data Management and Statistical Analysis: The data collected was entered in Microsoft Excel sheet. Percentage were calculated for categorical data, whereas numerical data represented as mean+/-SD. Statistical analysis was done to determine significant relationship between clinical and radiological factors to post-operative outcome. Paired T- test was used to compare preoperative and postoperative outcomes. Probability 3months 0 (0.0%) Most common fracture type involved in the study was burst fractures (19 patients, 43.2%) (table.3a). Most of the patients (23patients, 52.3%) in the study had moderate canal compromise (more than 50% obliteration of subarachnoid space, but not deforming the spinal cord) (table .3c). Most common level involved was D10 to L2 level (Thoraco-lumbar junction) 25 patients (56.8%) (table.3b). For most of the patients in the study surgery was done within 4weeks duration, (30 patients, 68.2%). For 14 patient surgery was done between 1-3 months duration (table.3d). Patients who underwent surgery for traumatic thoracolumbar spine fractures showed a mean improvement in grade of 0.43 and 0.76 in ASIA impairment scale postoperatively at 1month and 6 months respectively compared to preoperative status. These findings were found to be statistically significant (table.4a). Patients with paraparesis and paraplegia showed an improvement ASIA impairment scale of 1.06 and 1.25 grade respectively compared to preoperative scale, which was statistically significant Ttable.4b). a) Parameter Mean N Std. Deviation Difference t p value Pre ASIA 3.27 44 1.633 +0.43 5.25 .000 Post ASIA1* 3.70 44 1.579 Pre ASIA 3.33 43 1.614 +0.76 6.22 .000 Post ASIA6* 4.09 43 1.306 b) Symptom Parameters Mean N Std. Deviation mean difference t p value Paraparesis PreASIA 3.60 15 .632 +1.06 6.95 .000 Post ASIA6 4.67 15 .488 Paraplegia PreASIA 1.00 12 .000 +1.25 4.48 .001 Post ASIA6 2.25 12 .965 c) Parameter Canal Compromise N Mean Std. Deviation F P value Pre ASIA No/ mild 8 4.38 .744 17.278 .000 moderate 23 3.83 1.370 severe 13 1.62 1.193 Post ASIA6 No/ mild 8 4.75 .463 .463 .001 moderate 23 4.43 1.080 severe 12 3.00 1.477 d) Parameter Level N Mean Std. Deviation F P value Pre ASIA D1- D6 7 3.14 1.676 2.255 .081 D7-D9 6 1.67 1.633 D10-L2 25 3.48 1.584 L3-L5 2 4.00 .000 Multiple levels 4 4.25 .957 461 Outcome of patients undergoing posterior spine fixation and decompression Post ASIA D1- D6 7 3.86 1.676 1.449 .237 D7-D9 6 3.17 1.169 D10-L2 24 4.21 1.285 L3-L5 2 4.50 .707 Multiple levels 4 5.00 .000 e) Parameters Fracture type N Mean Std. Deviation F P value Pre ASIA Anterior wedge compression 11 4.27 1.009 7.29 .002 Burst 19 3.53 1.467 Translational injury/subluxation / Burst # + PLC injury 14 2.14 1.657 Post ASIA6 Anterior wedge compression 11 4.73 .467 6.38 .004 Burst 19 4.37 .955 Translational injury/subluxation / Burst # + PLC injury 13 3.15 1.725 Table 4. showing a)preoperative and post operative - ASIA impairment scale, . (I 1*-post operative at 1month, 6*- post operative at 6month), b))preoperative and postoperative - ASIA impairment scale among paraparesis and paraplegic patients c) relationship of canal compromise with preoperative ASIA (PreASIA) , and postoperative ASIA at 6month (Post ASIA6), d)relationship of level of injury with Pre ASIA and Post ASIA score at 6month, e)relationship of fracture type to Pre operative ASIA (PreASIA) ,Post operative ASIA at 6months (Post ASIA6). Table 6. showing a)pre operative and post operative KPS score (I*-immediate post operative, 1*-post operative at 1month, 6*- post operative at 6months), b) relationship of fracture type to post operative KPS at 6months (PostKPS6) , c)relationship of canal compromise with preoperative KPS (PreKPS) and postoperative KPS at 6months (Post KPS6). a) Parameter Mean N Std. Deviation Difference (improvement) t p value Pre KPS 39.8 44 11.91 +5.7 6.03 .000 Post KPS I* 45.5 44 11.30 Pre KPS 39.8 44 11.91 +25 13.09 .000 Post KPS1* 64.8 44 15.77 Pre KPS 40.0 43 11.95 +39.8 15.76 .000 Post KPS6* 79.8 43 18.32 b) Parameters Fracture type N Mean Std. Deviation F P value Post KPS6 Anterior wedge compression 11 90.9 13.75 7.73 .001 Burst 19 82.6 15.93 Translational injury/subluxation / Burst # + PLC injury 13 66.2 17.58 c) Parameter Canal Compromise N Mean Std. Deviation F P value Pre KPS No /mild 8 46.3 10.61 7.136 .002 moderate 23 42.6 12.51 severe 13 30.8 4.94 Post KPS6 No/ mild 8 92.5 13.89 10.766 .000 moderate 23 83.9 14.06 severe 12 63.3 17.75 Table 8. a) showing distribution of all patients return to job after surgery, b ) showing distribution of patients having weakness returning to job after surgery. a) Job No Modification Old same Job Total No. Of patients 19 (43.2) 17 (38.6) 8 (18.2) 44 (100.0) b) Weakness Job Total No Modification Old same Job ᵡ2 P VALUE 462 Geo Paul K. Jose, Tinu Ravi Abraham, P.K. Balakrishnan et al. No weakness 4 (26.7%) 4 (26.7%) 7 (46.7%) 15 (100.0%) 30.755 .000 monoparesis 0 (0.0%) 1 (100.0%) 0 (0.0%) 1 (100.0%) paraparsis 3 (20.0%) 11 (73.3%) 1 (6.7%) 15 (100.0%) paraplegia 12 (92.3%) 1 (7.7%) 0 (0.0%) 13 (100.0%) Total 19 (43.2%) 17 (38.6%) 8 (18.2%) 44 (100.0%) Pre ASIA Post ASIA6 A B C D E Total A 3 4 4 1 0 12 B 0 0 0 1 0 1 C 0 0 0 2 2 4 D 0 0 0 3 10 13 E 0 0 0 0 13 13 Total 3 4 4 7 25 43 Table 5. showing comparison of preoperative ASIA score (pre ASIA) to postoperative ASIA score at 6 months (post ASIA6). None of the operated patients had deterioration in ASIA score at 6month follow up. Of the total of 12 patients operated with preASIA grade A, only 3 patients remained at grade A, whereas 4 patients each had improved to ASIA grade B and C (table 5) on post-operative follow up at 6months. Preoperative ASIA impairment score showed significant relation to fracture type, with patients suffering from translational /distraction injury having a poorer grade (mean ASIA score of 2.14 = grade B to C) whereas anterior wedge compression fracture having better grades (mean ASIA score of 4.27= grade D to E). Post operatively ASIA impairment scale at 6 months showed significant relations to fracture type, with patients having anterior wedge compression fracture (mean ASIA score of 4.73= grade D to E) having better scores than patient with translational injury (mean ASIA score of 3.15= grade C to D) (table.4e). Considering canal compromise, patients with severe canal compromise were having poor ASIA score both preoperatively and postoperatively when compared with patients having mild / moderate canal compromise (table.4c). Regarding the level of involvement, patient with D7-D9 involvement were having lowest preoperative ASIA score (mean ASIA score was 1.67= A to B), but these finding didn’t have and statistical significance (table. 4d). Interval between injury and surgery failed to find any statistically significant relation in terms of outcome. When compared to preoperative KPS there was significant improvement in mean postoperative KPS score at 1month and 6 months as 25 and 39.8 respectively. (table.6a). Though preoperatively KPS failed to show any significant relation to fracture type, post operatively KPS at 6 months showed significant relation to fracture type, with patients having anterior wedge compression fracture (KPS=90.9) having better scores than patient with translational injury (KPS= 66.2) (table.6b). Considering canal compromise, patients with severe canal compromise were having poor KPS score both pre-operatively (mean=30.8) as well as post operatively (mean=63.3) when compared with patients having mild (mean preKPS =46.3, mean post KPS6 =92.5)/ moderate (mean preKPS =42.6, mean post KPS6 = 83.9) canal compromise (table.6c). KPS score didn’t have any significant relation with the level of injury. Considering the VAS pain scale, there was again significant decrease VAS pain scale in post-operative period (Immediately, at 1month and at 6 month scores being 1.65, 4.88 and 6.7 respectively-table.7). However, VAS pain scale didn’t show any significant relations to fracture type, canal compromise or the level of injury. Parameter Mean N Std. Deviation Difference (Decrease in pain) t p value PreVAS 7.70 44 .851 -1.65 7.975 .000 PostVAS I* 6.05 44 1.613 PreVAS 7.70 44 .851 -4.88 26.899 .000 PostVAS1* 2.82 44 .995 PreVAS 7.70 43 .860 -6.7 36.423 .000 . PostVAS6* 1.00 43 1.024 Table 7. showing preoperative and postoperative VAS pain score. (I*-immediate post operative, 1*-post operative at 1month, 6*- post operative at 6 months). Of the 44 patients operated, 25 patients (56.8%) were able to return to job. 8 patients (18.2%) were able to return to their old job (table.8a). Among the 13 patient operated with paraplegia only 1 patient (7.7%) was able to return to work with job 463 Outcome of patients undergoing posterior spine fixation and decompression modification and none of them were able to return to old job. But among 15 patients with paraparesis 12 (80%) were able to return to job (1 patient returned to the same job, rest 11 had to modify their job) (table. 8b). Bowel was involved in only 12 patients, of which 4 patients improved after surgery (33.3%) and in the rest 8 patients symptom remained same. Bladder was involved in 14 patients of which 4 patients improved (28.6%) and rest 10 patients remained symptomatically same. There was no worsening of bowel or bladder symptom following surgery (Table 9). Symptom Outcome after surgery Not involved worsen Same Improved Bowel 32 0 8 4 Bladder 30 0 10 4 Table 9. showing ouctome of bowel and bladder symptom following surgery. No significant relationship was found out between associated injuries or comorbidities to post- operative outcome. Intraoperative complication like pedicle breakage was seen in 3 patients. Other intraoperative complications like nerve root injuries were not observed. Postoperative complications like surgical site infection was seen in only 2 patients, discitis/ abscess and DVT was observed in 1 patient each. Other postoperative complications like implant failure were not observed. Post-operative complaint most commonly observed was stiffness in back at the operative site and was present in 25 patients (56.8%). DISCUSSION This retrospective study was done during the study period from 1st January 2019 to 31st December 2020, including 44 patients admitted for thoracic and lumbar spine fracture who had underwent posterior spine decompression and fixation. The study had 39 male patients (88.6%), with male to female ratio 7.8:1. The mean age of presentation was 44.30+/- 11.87yrs and most common age group of presentation was 30-50 yrs (59% patients) this again point to the fact that traumatic fractures mainly affects physically active age group and population (males). In a similar study done by Hariri O R et al between 2005 to 2015 among 46 patients, 93% patients were male and mean age of presentation was 36.8 years 9. Another comparative study done by Petr V et al in thoraco-lumbar spine fractures among 35 patients, again had 28 male patients and mean age of presentation as 42.4years10. As the study included only patients undergoing surgery for thoracic and lumbar fractures most common fracture type included in the study was burst fracture 43% (even though posterior element fracture and anterior compression fractures are far more common, as they are commonly managed conservatively, they are lesser in number in this study). In the study population thoraco-lumbar junction (D10-L2) was the most commonly involved fracture level (56.8%), probably due to the relative instability of transition zone. In the study of 66 patients by Roop Singh et al from 2007 to 2011 had reported similar results with about 57.6% (38 patients) thoracolumbar fracture occurring at D12, L1 levels11. Petr Vet al again had reported 80% of thoracolumbar fractures from D12, L1 levels10. Regarding the postoperative outcome the study showed improvement in ASIA impairment scale of 0.74 grade at 6 months postoperatively when compared with preoperative status. Among 43 patients followed up at 6 months (1patient lost in follow-up at 6month) no patients had deterioration in ASIA score. On post-operative follow up of 12 patients operated with preoperative ASIA grade A at 6 months only 3 patients remained at grade A , 4 patients each had improved to ASIA grade B and C, 1 patient to grade D and non to grade E (table.5). Among patients with paraparesis and paraplegic mean preoperative ASIA were 3.6 (ASIA grade C to D) and 1 (ASIA grade A). Their post-operative grade improved to 4.67 (ASIA grade D to E) and 2.25 (ASIA grade ~B) (table.4b). Although there was post- operative improvement in paraplegic patients, it was not up to functional levels. So, we can infer from the study that both paraplegic and paraparesis patient can have significant improvement in ASIA scale, but chance of paraplegic patients able to walk after surgery is rare. The study by Roop Singh et al among 66 patients also had similar observations with an improvement of average 1.03 grades in neurological status as per ASIA Impairment scale from the preoperative to final follow-up at one year11. Among 34 patients having preASIA grade A, 14 patients improved to grade B , 2 patients to grade D and non 464 Geo Paul K. Jose, Tinu Ravi Abraham, P.K. Balakrishnan et al. to grade E. The study also showed that the patients having incomplete lesions of the spinal cord showed more neurological improvement (mean, 1.5 grade) than the complete lesion of the spinal cord (mean, 0.53 grade). Similar observations were reported in another study by Butt et al 12. When ASIA score was assessed in terms of fracture type, as expected patients with anterior wedge compression fracture had better preASIA score (mean preASIA=4.27, ASIA D to E) compared to patient with translational /distraction injury (mean preASIA=2.14, ASIA B to C). This may be due to severe canal compromise / spinal cord injury associated with translation/ distraction injury. But postoperatively there was significant improvement in ASIA score at 6months for translation/distraction injury (post ASIA6=3.15, ASIA C to D) (mean improvement=1.01 grade) and burst fracture (post ASIA6= 4.37,ASIA D to E) (mean improvement = 0.84 grade). So we can expect a significant neurological improvement even in patients with translational / distraction injury on doing decompression + fixation. Patients with severe canal compromise were having preASIA score 1.62 (ASIA A to B) and with no/mild canal compromise were having preASIA score 4.38 (ASIA D to E). Here also post operatively patients with severe canal compromise were having significant improvement at 6month (post ASIA6= 3.00, ASIA C) (Mean improvement =1.38 grade). Similar improvement was seen in moderate canal compromise patients. So, we can expect a significant neurological improvement in patients with moderate to severe canal compromise, on doing decompression + fixation. There was no significant relation between level of injury and ASIA score but patients with D7-D9 level injury tend to have preASIA score very low (mean pre-ASIA =1.67, ASIA A to B) and 6month post- surgery there was significant improvement (mean post ASIA6= 3.17, ASIA C to D). Alessandro L et al in their study have reported poor ASIA score common for thoracic level vertebra fracture13. In our study, most of the patients underwent surgery within 4weeks of injury, (30 patients, 68.2%). For 14 patient surgery was done between 1-3 months duration (table.3d). Surprisingly there was no significant difference in improvement between early surgery group and late surgery group in terms of ASIA impairment scale. This is primarily because even in early surgery group most of the surgery were done after 1 week (partly because of lack of facilities for emergency stabilization of the spine and due to patient reporting late because of ignorance on the part of the patient or due to late referral from other centers). But study done on 27 patients between 2004 to 2006 by Sahika L C et al have reported surgical decompression and stabilization within 8 hours of spinal cord injury had better outcome than when operated between 3 and 15 days14. In the study by Roop Singh et al the patients of early surgery group showed slightly better improvement in mean ASIA score (1.2 grade) than the patients who had underwent surgery late (0.95 grade), which was not a statistically significant difference11. Chadha et al and Butt et al.had also reported a fair neurological recovery in cases were surgery was done late12,15. Compared to preoperative KPS score (mean PreKPS=39.8) there was significant improvement in mean post-operative KPS score at 1month (mean PostKPS1=64.8) and 6 months (mean post KPS6= 79.8) as 25 and 40 respectively. So, at 6months follow up on an average the patient in the study were able to carry out normal activity with signs and symptoms of disease (KPS=80). Similar results were seen in a study done by Mohsen K et al who compared the outcome after surgery and conservative management among 25 patients. In this study JOABPEQ (JOA Back Pain Evaluation Questionnaire) was used to assess the functionality in five domains including walking ability, lumbar function, low back pain, social life function and mental health at admission and at the interval of 3, 6, 12 months after treatment. In both surgery and conservatively managed patients there was improvement in outcome, but faster and better recovery was among post-surgery group16. In our study fracture type and KPS score didn’t have significant relation in preoperative period. Postoperatively at 6months KPS showed significant relation to fracture type with patients with anterior compression fracture having mean KPS score as 90.9, and those with translation / distraction injury having mean KPS as 66.2. So, even though there was improvement in KPS score in all types of fractures, anterior wedge compression fracture followed by burst fracture tend to have best improvement in terms of KPS score after 6months of surgery. In terms of canal compromise, pre-operative KPS for no/mild, moderate and severe were 46.3, 42.6 and 30.8 respectively which improved to 92.5, 83.9 and 465 Outcome of patients undergoing posterior spine fixation and decompression 63.3 at 6month post operatively. So, improvement in KPS score in no/ mild, moderate, severe canal compromise were 46.2, 41.3 and 32.5 respectively. So, there was better improvement in KPS score in mild and moderate canal compromise patients compared to severe canal compromise patients. These findings may be partly due to absolute bed rest advised for all patients prior to surgery, hence irrespective of fracture type and canal compromise preoperative KPS will be low for all, whereas postoperatively patients with less severe injury have far better improvement in KPS score. Compared to preoperative status, postoperatively there was significant decrease in VAS pain scale - immediately post op, at 1month post op and at 6-month post op as 1.65, 4.88 and 6.7 respectively (table.4). VAS pain scale didn’t find any significant relation in terms of fracture type, canal compromise both preoperatively as well as post operatively. Study by Rajdeep S B et al on 30 patients conservatively managed had mean VAS score of 9.77 ± 0.43, which decreased to 2.03 ± 0.90 at the end of 2 years17. Study by Roop singh et al had quantified pain using Denis pain scale and found out 48.48% patient had mild to no pain, and 42.42% patient had moderate pain at 1 year follow up11. Regarding outcome in terms of job, postoperatively at 6months follow up 19 patients (43.2%) were not having job, of which 12 were paraplegic initially itself. Among 13 patient having paraplegia initially, only 1 returned to job (7.7%) with job modification, none of them were able to returned to same job. Whereas, of the 15 patients having paraparesis 12 (80%) of them returned to job, but 11 of them had to modify their job. In patients having no weakness, 11 patients (73.3%) were able to return to job, of which 7 patients (46.7%) were able to return to old job itself. So, paraplegia in initial presentation implies a very poor outcome in terms of job. Patients with no weakness or paraparesis in initial presentation tend to return to same job or to a modified job. Study by Roop singh et al had reported 63.4% patients not returning to job (most of them were initially paraplegic) and 36.6% patients returning to work (half of them with job modification)11. Leferink et al. had reported, 50% of patients changed the intensity of their work or the kind of work they did, after thoracolumbar spine injury and treatment18. Study by Briem D et al also had reported a low work capacity after thoracolumbar spine fractures19. was involved in only 12 patients, of which 4 improved after surgery (33.3%) and rest 8 symptom remained same. Bladder was involved in 14 patients, of which 4 patients improved (28.6%) and for rest 10, symptoms remained same. There was no worsening of bowel or bladder symptom following surgery (table.7). So, there is around one third chance of improvement by surgical decompression when bowel and bladder is involved in thoracolumbar spine fracture. In literature review a study by Ping- Yeh Chiu et al among 8 patients from 2005 to 2012 with pure conus medullaris syndrome with thoracolumbar burst fracture, 5 patients regained self-voiding function20. In our study no significant relationship was found out between associated injury or comorbidity to post-operative outcome. Complications observed in the study were intraoperative pedicle breakage in 3 patients, postoperative surgical site infection in 2 patients, discitis/ abscess and DVT was observed in 1 patient each. Other complications like nerve root injury and implant failure were not seen. Though there was no implant failure reported in 6-month follow up (which may be an advantage of fixation of 2 levels above and below the spine fracture), most of the patients (56.8%) complaint of stiffness in back at operative site. In transpedicular screw fixation it is recommended to include two spinal levels above the fracture level and one or two levels caudal to the fracture level21. Such long segment spinal fixation might result in significant loss of mobility and increased risk for adjacent level morbidity. In an attempt to lessen the problem arising due to decreased mobility, short segment instrumentation has been introduced, fusing only two motion segments. But it also has come up with mixed results and complications22,23. On literature review the study by Butt MF et al.says more than 50% of patients had one or more complications, including 18 cases of hardware failures, involving 20 pedicle screws12. Complications reported in study by Roop Singh et al were single level above and below the fracture site was fused had only one implant failure such as nut loosening (asymptomatic), 4misplaced screws (in 3 patients -asymptomatic)11. Chadha et al had reported misplacement of the screw in 3 cases, one case of screw loosening and one screw pullout15. 466 Geo Paul K. Jose, Tinu Ravi Abraham, P.K. Balakrishnan et al. CONCLUSION From this retrospective study, we can conclude that laminectomy and decompression of the spinal cord and posterior spine fixation 2 levels above and below, using polyaxial screws and rods is safe, reliable and effective method in the management of thoraco-lumbar fractures. There was significant improvement in ASIA impairment scale (mean improvement at 6months=0.74 grade) , KPS score (mean improvement at 6months= 40) and VAS pain scale (mean improvement at 6months= 6.7) at 6 months follow up after surgery. Study was able to find out that the improvement in ASIA impairment scale was more in patient with severe canal compromise (mean improvement at 6months=1.62 grade), patients with translational/ distraction injuries (mean improvement at 6months= 1.01grade) and patients with paraparesis /paraplegia (mean improvement at 6months= 1.06/1.25 grade respectively). Only one third patients with bowel and bladder involvement improved after decompressive surgery. Around 56.8% patients were able to return to job (either same job or with some modification) at 6 months follow up. Patients who were paraplegic at initial presentation, were mostly not able to return to job. Most common reported complication in the study was intraoperative pedicle breakage. ABBREVIATIONS ASIA - American Spine Injury Association Scale KPS - Karnofsky Performance Status Scale VAS - Visual Analog Scale MRI - Magnetic Resonance Imaging CT - Computed Tomography DECLARATIONS Funding: self Conflict of interest: none declared Ethical approval: Obtained (IRB No.-61/2021) ACKNOWLEDGEMENTS Dr. Shaju Mathew, Associate Professor, Department of Neurosurgery Dr. Vinu V. 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