To Evaluate Post-operative Functional and Radiological Outcomes of Patients with Dorsal and Dorsolumbar Pott's Spine who Underwent Anterior Decompression and Posterior Instrumentation, through Only Posterior Trans-Pedicular Approach
Authors: Mohapatra Bibhudendu 
Published: April 2016

Introduction

Approach for surgical treatment of Thoraco-lumbar tuberculosis has been always controversial. Traditionally, the anterior approach has been preferred throughout the spine to achieve these goals. A combined anterior plus posterior approach helps to overcome stability related drawbacks of anterior approach alone. Posterior approach has gained popularity in the last decade as it provides excellent exposure for circumferential spinal cord decompression and also allows posterior instrumentation to be extended for multiple levels above and below the level of pathology with less morbidity, less duration of surgery as well as less amount of blood loss as compared with combined anterior and posterior approach.

Material and Methods

The study was conducted at Indian spinal injuries center, New Delhi during the period from June 2014 to June 2015 and included all patients of thoracic and Thoraco-lumbar Pott's disease who were operated by posterior trans-pedicular approach procedure from January 2009 to January 2014. Out of 560 patients who underwent surgery only 60 patients were included in the study who satisfied the following criteria: Age ≥ 18 years.and minimum up to 12 months of clinic-radiological follow up. Following data were collected and analyzed: Average operative time, pre and post AIS grading, bony fusion, pre-op, post op and last follow up angles of kyphosis, loss of kyphotic correction, cage subsidence, implant loosening, implant failure, ODI and VAS scores at 6 months interval and final follow up. The pre-op, post op and last follow up angles were compared for dorsal and lumbar separately using paired t-test or Wilcoxon Signed rank test (if data are non parametric) and was corrected using Bon-ferroni for multiple comparisons.

Results

Patients were followed up for at least twelve months, with an average of 16.81 months (range 12–40months). The mean operation time was 260 ± 30 minute (range 180– 540 minute). 55 patients presented the evidence of successful bony fusion within a mean time of 6 ± 1.5 months. Dorsal ( n = 50): The pre op angles (19.85 ± 14.17) were significantly larger than the post op angles (6.96 ± 14.8) ( p < 0.00001) and smaller than the last follow up angle (9.29 ± 16.19) ( p < 0.0001) as tested by Wilcoxon Signed rank test. Lumbar ( n = 10): The pre op angles (21.45 ± 7) were significantly larger than the post op angles (11.6 ± 4.4) (t score = 4.01, p = 0.003) and smaller than the last follow up angle (13.4 ±4.1) (t score = −3.668, p = 0.005). Pre op VAS scores (8.15 ±0.9) was higher than the post op values (2.18 ± 0.9) (t score =52.38, p < 0.00001) and the last follow up (0.833 ± 0.88). Pre op ODI scores (32.5 ±6.4) was higher than the post op values (13.4 ± 5.8) ( p < 0.00001) and at last follow up (3.966) as tested by Wilcoxon Signed rank test.

Conclusion

Anterior decompression and posterior instrumentation through only trans-pedicular approach is a safe surgery with less intra operative surgical duration and improve neurological, radiological, pain and functional scores significantly with significant fusion rates and less post operative morbidity. Limitation of the study are retrospective study, small sample of 60 patients and radiographs used to assess fusion instead of CT scan.