A Whole Spine MRI Based Study of the Prevalence, Associated Disc Degeneration and Anatomical Correlations of Lumbosacral Transitional Vertebra.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Lumbosacral transitional vertebra (LSTV) results in numerical alterations of the lumbar and sacral segments. Literature concerning true prevalence, associated disc degeneration, and variation in numerous anatomical landmarks concerning LSTV is lacking. METHODS: This is a retrospective cohort study. The prevalence of LSTV was determined in whole spine MRIs of 2011 poly-trauma patients. LSTV was identified as sacralization (LSTV-S) or lumbarization (LSTV-L) and further sub-classified into Castellvi's and O'Driscoll's type respectively. Disc degeneration was evaluated using Pfirmann grading. Variation in important anatomical landmarks was also analysed. RESULTS: Prevalence of LSTV was 11.6% with 82% having LSTV-S. Castellvi's type 2A and O'Driscoll type 4 were the commonest sub-types. LSTV patients demonstrated considerably advanced disc degeneration. The median termination level of conus medullaris (TLCM) in non- LSTV and LSTV-L groups was at middle L1 (48.1% and 40.2%) while in the LSTV-S group, it was at upper L1 (47.2%). The median level of right renal artery (RRA) in non- LSTV patients was at middle L1 in 40.0% of individuals while in the LSTV-L and LSTV-S groups, it was at upper L1 level in 35.2% and 56.2% respectively. The median level of abdominal aortic bifurcation (AA) in non-LSTV and LSTV-S patients was at middle L4 in 83.3% and 52.04% respectively. However, in the LSTV-L group, the most common level was middle L5 (53.6%). CONCLUSION: The overall prevalence of LSTV was 11.6%, with sacralization accounting for more than 80%. LSTV is associated with disc degeneration and a variation in the levels of important anatomical landmarks.

Ossification of Posterior Longitudinal Ligament in Cervical Spine and Its Association With Ossified Lesions in the Whole Spine: A Cross-Sectional Study of 2500 CT Scans.

STUDY DESIGN: A retrospective study. OBJECTIVE: To identify the prevalence and characteristics of ossified posterior longitudinal ligament (OPLL) in the cervical spine and its association with other spinal ligament ossifications. METHOD: This study is a retrospective review of whole spine CT scans of polytrauma patients from 2009 to 2018. Patients were screened for cervical OPLL (C-OPLL), thoracolumbar OPLL, thoracic ossified ligamentum flavum (OLF), cervical and thoracolumbar ossified anterior longitudinal ligament (C-OALL AND T-L OALL), ossified nuchal ligament (ONL) and, diffuse idiopathic skeletal hyperostosis (DISH) using CT scans. Their prevalence and distributions were assessed using statistical tools. Chi-square tests were used to determine statistical association between the categorical parameters. RESULTS: Out of 2500 patients, 128 had C-OPLL with a prevalence rate of 5.12% with mean age of 55.89 year. The most commonly affected level was C5, followed by C6, and C4. The segmental OPLL was highest in number (77.7%), followed by localized type (14.8%). While the prevalence rate of thoracic OPLL was 0.56%, OLF was 9.9%. Ossifications that coexisted along with C-OPLL were thoracic OPLL (7.81%), thoracic OLF (36.71%), cervical OALL (29.68%), thoracolumbar OALL (37.5%), DISH (27.34%) and, ONL (7.03%). CONCLUSION: Our study indicated a prevalence rate of 5.12% for C-OPLL with a predominance of segmental OPLL (77.7%). Among these patients, approximately 36% had coexisting thoracic OLF. In patients with symptomatic OPLL induced cervical myelopathy, MRI analysis of whole spine with relevant CT correlation may help in detecting additional ossification sites of compression.

The analysis of progression of disc degeneration in distal unfused segments and evaluation of long-term functional outcome in adolescent idiopathic scoliosis patients undergoing long-segment instrumented fusion.

PURPOSE: To analyse the progression of disc degeneration in distal unfused lumbar segments in post-operative Adolescent Idiopathic Scoliosis (AIS) patients; and to evaluate pre-operative and post-operative radiological parameters associated with progressive disc degeneration. METHODS: A retrospective study of patients, who underwent surgery for AIS between 2006 and 2013 at a tertiary-care spine hospital, was conducted. Only patients aged between 11 and 18 years, who underwent deformity correction surgery with pedicle screw-only constructs, minimum of 6.5 year follow-up, and complete radiological data, and were included. On plain radiographs, coronal cobb's angle (CCA), apical translation, lower instrumented vertebra tilt (LIV tilt), LIV-Sacral angle, and sagittal spinal and pelvic parameters were measured. Disc degeneration was assessed on Magnetic Resonance Imaging (MRI) using Pfirrmann's grading. Total endplate score (TEPS) and facet degeneration (by Fujiwara's grading) were also measured. Based on the difference in progression of disc degeneration, patients were classified as Pfirrmann's grade static (PGS) and Pfirrmann's grade progressive (PGP) groups. Comparison of all pre- and post-operative parameters was made between PGS and PGP groups, and statistically analyzed. Functional evaluation was performed using SRS-22 score. RESULTS: A total of 58 patients were finally included. The mean follow-up was 9.1 years. 43 (74.1%) and 15 (25.9%) patients were classified under PGS and PGP groups, respectively. Among the15 patients in PGP group, selected LIV was L4 in 8, L3 in 3, L1 in 3, and L2 in 1. Among them, 11 patients (73.3%) progressed from grade 1 to grade 2. In the remaining 4 (26.6%), Pfirrmann's grade progressed to ≥ 3. The progression of disc degeneration did not correlate with age or sex distribution (p = 0.3), pre-operative and post-operative TEP scores (p = 032), pre-operative disc or facet degeneration (p = 0.52), number of unfused spinal segments (p = 0.56), pre-operative or post-operative coronal (p = 0.42), or sagittal spinal (p = 0.27) or pelvic parameters (p = 0.14). The final functional outcome (SRS-22) was not significantly different between PGS and PGP groups (p = 0.67). CONCLUSION: 74% of AIS patients demonstrated no signs of progressive disc degeneration at an average follow-up of 9.1 years. 26% (15/58) of AIS patients demonstrated progressive disc degeneration, among whom, degeneration progressed by only 1 Pfirrmann's grade in 74% (11/15). In the remaining four patients, disc degeneration progressed to Pfirrmann's grades 3 or greater. There was no correlation between higher grades of disc degeneration and lower instrumented vertebra (LIV) or functional outcomes scores (SRS-22).

Cervical sagittal alignment in Lenke 1 adolescent idiopathic scoliosis and assessment of its alteration with surgery: a retrospective, multi-centric study.

PURPOSE: To document baseline cervical sagittal characteristics in Lenke 1 adolescent idiopathic scoliosis (AIS) patients and assess the alteration in these parameters with surgery. METHODS: Pre-operative and 2-year postoperative radiographs of 82 Lenke 1 AIS patients recruited from five hospitals were analysed. Selected radiographic parameters capturing regional and global sagittal alignment were measured. Comparison was made between groups based on baseline thoracic kyphosis (TK: TK < 20°, TK ≥ 20°). Pre-operative and postoperative values were compared-the change in each radiographic parameter was correlated with the degree of sagittal and coronal correction. RESULTS: At baseline, TK was 29.8° ± 16°, cervical lordosis (CL) was - 1° ± 14°, lumbar lordosis (LL) was - 57.1° ± 21°, C2-C7 sagittal vertical axis (SVA) was 16 ± 14 mm and C7-S1 SVA was - 15 ± 28 mm; 44% of patients had cervical kyphosis. Patients with thoracic hypokyphosis had a significantly lower LL and more kyphotic cervical spine compared to those with thoracic normohyperkyphosis. The effect of surgery on TK depended on pre-operative thoracic sagittal alignment-TK increased in patients with thoracic hypokyphosis, but decreased in patients with thoracic normohyperkyphosis. Neither CL nor C2-C7 SVA changed significantly with surgery; 46% of patients still had cervical kyphosis postoperatively. CONCLUSION: There is a high incidence of cervical kyphosis at baseline in AIS patients-more so in those with pre-operative thoracic hypokyphosis. Unlike TK, CL is not significantly altered with surgery-improvement in CL correlates weakly with sagittal correction of the structural curve.

Macrodystrophia Lipomatosa of Thoracic Spine Causing Progressive Neurodeficit: A Case Report and Review of Literature.

CASE: We report the first case of a 21-year-old male patient with macrodystrophia lipomatosa (MDL), with local gigantism involving the thoracic spine and progressively worsening neurodeficit. Imaging studies revealed fatty infiltration and hypertrophied intercostal nerves, dextroscoliosis, osseous hypertrophy between C4 and T2, and severe canal stenosis at the T4 to T5 level secondary to lamino-facetal hypertrophy. He underwent debulking of the lesion and posterior instrumented decompression in a staged manner. His neurodeficit improved postoperatively and was ambulant without support at the end of the 2-year follow-up. CONCLUSION: Surgery in patients with MDL is technically challenging and fraught with complications such as neurological deficit and significant blood loss.

Symptomatic Unilateral Pediculolysis Associated with Contralateral Spondylolysis and Spondylolisthesis in Adults-Case Report and Review of Literature.

BACKGROUND: The term "pediculolysis" encompasses rare, chronic pedicular changes characterized by pedicle hypertrophy, sclerosis, and pseudoarthrosis, which develop secondary to recurrent microfractures from repeated stress injuries. These stress injuries to pedicles can be insufficiency fractures, commonly reported in elderly patients with associated osteoporosis, or fatigue fractures, which occur in young adolescents involved in heavy sports. These pedicular lesions have been reported in association with defects in other components of the neural arch, including the pars interarticularis and lamina. CASE DESCRIPTION: We have described a rare case of grade 1 spondylolisthesis with left-sided pediculolysis and contralateral pars lysis in a middle-age female patient without associated osteoporosis or comorbidities. She underwent L5-S1 transforaminal lumbar interbody fusion after initial conservative measures had failed. However, her symptoms persisted even after the surgery and necessitated revision surgery, including left L5 medial pediculectomy, neurolysis of the left L5 nerve root, and extension of instrumentation to L4 bilaterally and L4-L5 posterolateral fusion. CONCLUSION: We have reported the present case to bring awareness to spine surgeons regarding the existence of this rare entity even in middle-age individuals. From our experience with the present patient, we believe that for patients with L5 pediculolysis and spondylolisthesis, the option of L5 medial pediculectomy and extension of instrumentation to L4 level should be considered.