Drug resistance patterns in 111 cases of drug-resistant tuberculosis spine.

PURPOSE: We report the largest study conducted till date of drug resistant tuberculosis in spine analyzing the drug susceptibility patterns in 111 cases of proven drug resistance. METHODS: An observed cross-sectional study was conducted. Six-hundred and eighty-six patients with positive cultures underwent sensitivity testing to 13 commonly used anti-tubercular drugs using BACTEC MGIT-960 system. RESULTS: Females (60.3%) outnumbered males (39.6%). Only three patients (2.7%) were found HIV positive, and none of these had AIDS. Forty-four (39.6%) patients had taken AKT in the past for some form of tuberculosis. Eight (7.2%) patients had history of treatment default. The drug sensitivity testing revealed 87 (78.3%) cases of multi drug resistance (resistance to both isoniazid and rifampicin) and 3 (2.7%) cases of XDR-TB spine. Of the individual drugs, widespread resistance was present to both isoniazid (92.7%) and rifampicin (81.9%), followed by streptomycin (69.3%). Least resistance was found to kanamycin, amikacin and capreomycin. CONCLUSION: It is recommended to do routine biopsy, culture and drug sensitivity testing in all patients of tuberculosis spine to guide selection of appropriate second-line drugs when required. In cases of non availability of drug susceptibility testing despite repeated attempts, it is suggested to use data from large series such as this to plan best empirical chemotherapy protocol.

Surgical patterns in osteoporotic vertebral compression fractures.

PURPOSE: To report morphological patterns of osteoporotic vertebral compression fractures (OVCFs) presenting for surgery. To describe surgical options based on fracture pattern. To evaluate clinical and radiological outcome. METHODS: Forty consecutively operated OVCFs nonunion patients were retrospectively studied. We define four patterns of OVCFs that needed surgical intervention. Group 1 mini open vertebroplasty (N = 10) no neurologic deficits and kyphotic deformity, but with intravertebral instability and significant radiological spinal canal compromise. Group 2 with neurologic deficits (N = 24) (2A)-transpedicular decompression (TPD) with instrumentation (N = 14). Fracture morphology similar to (1) and localized kyphosis <30° (2B)-pedicle subtraction osteotomy (PSO) with instrumentation (N = 10). Fracture morphology similar to (1) and local kyphosis >30°. Group 3 posterolateral decompression with interbody reconstruction (N = 06) endplate(s) destroyed, with instability at discovertebral junction, with neurologic deficit. Average follow-up was 34 months. VAS, ODI and Cobb angle were recorded at 3, 6, 12 months and yearly. RESULTS: There was significant improvement in the clinical (VAS and ODI) scores and radiologic outcome in each group at last follow-up. 30 patients out of 40, had neurologic deficits (Frankel's grade C = 16, Frankel's grade D = 14). The motor power gradually improved to Frankel's grade E. Average duration of surgery was 97 min. Average blood loss was 610 ml. CONCLUSION: Different surgical techniques were used to suit different fracture patterns, with good clinical and radiological results. This could be a step forward in devising an algorithm to surgical treatment of OVCF nonunions.

Geoelectric characterisation of the junction of seismically active Delhi Hardwar Ridge and Delhi Sargodha Ridge.

A magnetotelluric (MT) geophysical survey for the first time has been conducted for the geoelectric characterization of the junction of the contact zone of NNE-SSW striking Delhi Hardwar Ridge (DHR) and NW-SE trending Delhi Sargodha Ridge (DSR) in the Rohtak area, Haryana which has experienced 15 earthquakes of M2.0-M4.4 from April to August 2020. A total of 08 MT sites are acquired along a NW-SE profile of length 50 km. From the 2D MT data inversion, the DHR and DSR are for the first time characterized by equal values of moderate resistivity of 100 Ohm m at two depths. The resistivity variation for DHR corresponds to 100 Ohm m from the surface to the depth of 20 km, whilst DSR is found associated with the same value of resistivity extending in the NW direction. The DHR has been found striking NE-SW with a very shallow central axis (less than 400 m) having a width of 12-15 km forming half grabens on both limbs supported by shallow faults. The DSR has been found bifurcated from DHR at a depth of 12-13 km and extended in the NW direction. The DSR has been generated due to flexure bulging caused by collision and anticlockwise rotation of the Indian plate in the Eocene period. A NE striking steep dipping reverse fault (F1) has also been identified about 15 km west of the DHR. It is inferred that the DSR got upthrusted along this fault and became shallower in the NW region. The seismicity in the Rohtak and surroundings is located at the bifurcation points of DHR and DSR and the contact zone of DSR and reverse fault F1. The reverse fault F1 is also active and has generated microseismicity in the past.

Role of 'low cost Indian implants' in our practice: our experience with 1,572 pedicle screws.

PURPOSE: As Indian spine surgeons, we have to choose between 'foreign implants' and 'Indian implants'. An Indian four pedicle screw rod construct costs 330 US dollars (one-third that of a similar foreign construct). About 60% of patients cannot afford expensive foreign implants. There is little written data evaluating how these Indian implants fare. The purpose of our study was to evaluate implant failure rate with Indian implants and compare it to foreign implants. METHODS: We analysed results of 1,572 titanium pedicle screws used in 239 patients with a minimum 1-year follow-up. Patients were divided into Indian and foreign implant groups. Radiological failures were classified as (1) surgery and disease failure, (2) bone failure and (3) implant failure. The null hypothesis was that there is no difference between implant failure rate for Indian and foreign implants. RESULTS: A total of 128 (53.56%) of patients could not afford foreign implants. We used 679 foreign and 893 Indian pedicle screws. In foreign implant group, there was a single incident of implant failure (0.15%). In Indian implant group, there were five such incidents (0.56%). CONCLUSIONS: (1) Rate of failure for 'low cost' Indian implants is very low (approximately 1 implant complication for every 200 screws). (2) There is no statistically significant difference in failure rates for Indian implants and foreign implants (P-value = 0.2438). We recommend that Indian implants are a safe and viable option to make spine surgery cost effective in the Indian scenario.

A holistic seismotectonic model of Delhi region.

Delhi region in northern India experiences frequent shaking due to both far-field and near-field earthquakes from the Himalayan and local sources, respectively. The recent M3.5 and M3.4 earthquakes of 12th April 2020 and 10th May 2020 respectively in northeast Delhi and M4.4 earthquake of 29th May 2020 near Rohtak (~ 50 km west of Delhi), followed by more than a dozen aftershocks, created panic in this densely populated habitat. The past seismic history and the current activity emphasize the need to revisit the subsurface structural setting and its association with the seismicity of the region. Fault plane solutions are determined using data collected from a dense network in Delhi region. The strain energy released in the last two decades is also estimated to understand the subsurface structural environment. Based on fault plane solutions, together with information obtained from strain energy estimates and the available geophysical and geological studies, it is inferred that the Delhi region is sitting on two contrasting structural environments: reverse faulting in the west and normal faulting in the east, separated by the NE-SW trending Delhi Hardwar Ridge/Mahendragarh-Dehradun Fault (DHR-MDF). The WNW-ESE trending Delhi Sargoda Ridge (DSR), which intersects DHR-MDF in the west, is inferred as a thrust fault. The transfer of stress from the interaction zone of DHR-MDF and DSR to nearby smaller faults could further contribute to the scattered shallow seismicity in Delhi region.

Congenital absence of the posterior arch of the atlas with concomitant fusion to the axis: a case report.

We present a 52-year-old man with congenital absence of the posterior arch of the atlas and concomitant fusion of the posterior tubercle of the atlas to the spinal process of the axis. He had normal reflexes and no motor deficit. He underwent C3-C7 laminoplasty and achieved good outcome.

Posterior approach in thoracolumbar tuberculosis: a clinical and radiological review of 67 operated cases.

(1) To present the indications of single stage all posterior surgery in thoracic and lumbar tuberculosis. (2) To evaluate the results of single stage all posterior surgery. We analysed 67 patients who underwent single stage all posterior surgery with follow-up of 31.37 months. We performed the following operative procedures depending upon level and case requirements. (Group A) Instrumentation alone for instability. (Group B) Transpedicular decompression and instrumentation for neurological compression in thoracic and thoracolumbar spine. (Group C) Transforaminal approach for access to anterior column in lumbar spine in addition to posterior instrumentation. (Group D) Pedicle subtraction osteotomy and instrumentation for deformity correction. (Group E) Posterior decompression alone for isolated posterior epidural compression. (Group F) Reconstruction of anterior column by all posterior approach. Thirty-eight had neurological deficit whereas 29 were Frankel E. In 12 cases, anterior reconstruction was done. In the remaining 55 cases, we relied on vertebral reconstitution under chemotherapy. Operative time was 150.5 min and blood loss was 514.18 ml. Of 38 patients with deficit, 34 improved. There was radiological fusion in all patients. Pre- and post-operative Cobb's measurements were 9.95 and 8.1, respectively, in thoracic and thoracolumbar spine and -9.39 and -11.42, respectively, in lumbar spine. Of 55 cases where anterior reconstruction was not done, only 3 had progression of Cobb's >10°. Posterior approach can achieve adequate decompression of offending middle column and if required, even anterior reconstruction. Posterior approach is versatile, with many surgical options depending on the level and case requirements.

Visual loss after spine surgery.

Incidence of perioperative visual loss ranges from 0.06% to 0.2% with the most common cause as ischemic optic neuropathy. We report one-year follow up of a 50-years-old hypertensive housewife who underwent lumbar decompression and fusion for degenerative scoliosis, but woke up with painless unilateral visual loss. Fundus examination was normal. Her visual acuity improved from initial finger counting close to face to finger counting at 3 m at 1 year. Identification of high risk patients may help in appropriate preoperative counselling, prevention and early recognition of this devastating complication.

Postvertebroplasty instability.

Vertebroplasty provides excellent pain relief and functional restoration for osteoporotic fractures. Short-term complications such as cement leak and embolism are well described. Incident fractures are the only well-reported long-term complications. The authors describe the cases of 5 patients who presented with back pain caused by instability or worsening neurological status 13 months (range 8-17 months) after vertebroplasty. They further classify this postvertebroplasty instability into intervertebral instability and intravertebral instability, depending on the apex of abnormal mobility. One patient presented with cement migration and progressive collapse of the augmented vertebral body. Another patient presented with an additional fracture. Both cases were classified as intravertebral instability. The cases of 3 other patients presenting with adjacent endplate erosion, vacuum disc phenomenon, and bridging osteophyte formation were classified as having intervertebral instability. Long-term effect of cements on the augmented vertebral body and adjacent endplates and discs is a cause for concern. Vertebroplasty acts as a mechanical stabilizer and provides structural support but does not bring about union. Micromotion has been shown to persist for years after vertebroplasty. This study describes persistent instability after vertebroplasty in a series of 5 cases. The authors propose that postvertebroplasty instability occurs due to collapse of soft osteoporotic bone and endplates around cement. All 3 cases of intervertebral instability were associated with an intradiscal cement leak. With increased longevity and higher functional demands of the geriatric population, the durability of this "rock (cement) between cushions (of osteoporotic bone)" arrangement (as seen in vertebroplasty) will be increasingly challenged.