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.

     

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.     

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.     

Outcome of single level instrumented posterior lumbar interbody fusion using corticocancellous laminectomy bone chips

Background:

Interbody fusion surgery has been considered by many to be a treatment of choice for instability in lumbar degenerative disc disease. A posterior lumbar interbody fusion (PLIF) has the advantages of spinal canal decompression, anterior column reconstruction, and reduction of the sagittal slips from a single posterior approach. The PLIF using double cage was a standard practice till many studies reported comparable results and lesser complications with single cage. Iliac crest was considered as an appropriate source of bone graft until comparable spinal fusion rates using local bone graft and cage emerged. Till date, there has been no report of corticocancellous laminectomy bone chips alone being used for spinal fusion. In this paper, we present radiologic results of single level instrumented PLIF, where in only corticocancellous laminectomy bone chips were used as a fusion device.

Materials and Methods:

It is a retrospective cohort study of 35 consecutive patients, who underwent single level instrumented PLIF surgery, wherein only locally obtained bone chips was used for spinal fusion. The average follow-up was 26 months. The indications for the surgery were as follows: 19 patients had disc herniations, with back pain of instability type, normal disc height on radiology. Ten patients had grade 1 spondylolisthesis, with significant back pain and translational instability on radiography. Three patients were redo spine surgeries, and three patients had healed spondylodiscitis with significant back pain and instability. All patients were regularly followed up and decision of spinal fusion or no fusion was taken at 2 years using modified criteria of Lee.

Results:

Of total 35 patients, there were 24 males and 11 females, with a mean age of 41 years. There were 16 patients with definitive fusion, 15 patients with probable fusion, 04 patients with possible pseudoarthrosis, and no patient had definitive pseudoarthrosis. The mean time for fusion to occur was 18 months. The average loss of disc height, over 2 year follow up, was only 3 mm in 8 patients. Three patients had a localized kyphosis of more than 3° at the fusion level. The average blood loss was 356 ml and average operating time was 150 min.

Conclusion:

Corticocancellous laminectomy bone chips alone can be used as a means of spinal fusion in patients with single level instrumented PLIF. This has got a good fusion rate.     

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.