Arvind Jayaswal

Safety of 3 Different Reintroduction Regimens of Antituberculosis Drugs after Development of Antituberculosis Treatment–Induced Hepatotoxicity

BACKGROUND Drug-induced hepatotoxicity (DIH) is the most common adverse drug reaction leading to interruption of antituberculosis treatment. Worldwide, different reintroduction regimens have been advocated, but no consensus guidelines are available. Reintroduction of antituberculosis drugs in patients with DIH has never been studied systematically. We aimed to compare the safety of 3 different reintroduction regimens of antituberculosis drugs in patients with antituberculosis DIH. METHODS A total of 175 patients with a diagnosis of antituberculosis DIH were randomized to receive 1 of 3 different predefined reintroduction regimens of antituberculosis drugs and were evaluated prospectively. Patients in arm I were given isoniazid, rifampicin, and pyrazinamide simultaneously at full dosage from day 1. In arm II, drugs were administered in a manner similar to that recommended in the American Thoracic Society guidelines for reintroduction. In arm III, drugs were administered in accordance with British Thoracic Society guidelines. RESULTS Nineteen patients (10.9%) had recurrence of DIH during follow-up. Eight, 6, and 5 patients had recurrence of hepatitis in arms I, II, and III, respectively (P = .69). Of all the clinical and laboratory parameters, pretreatment serum albumin level was the only statistically significant predictor of future recurrence of DIH on reintroduction of antituberculosis drugs (P < .01). CONCLUSIONS The recurrence rate of hepatotoxicity was not significantly different between the 3 groups. According to the findings of the present study, all 3 of the potentially hepatotoxic drugs (isoniazid, rifampicin, and pyrazinamide) can be reintroduced simultaneously at full dosage safely from day 1, especially for patients with bilateral extensive pulmonary tuberculosis, to halt disease transmission or to treat patients with life-threatening tuberculosis. TRIAL REGISTRATION ClinicalTrials.gov identifier number: NCT00405301.

Outcome-based Classification for Assessment of Thoracic Pedicular Screw Placement

Study Design. Prospective cohort study. Objective. We propose a simple outcome-based classification for assessment of pedicle screw positions based on postoperative computed tomography scan. This bridges the gap between high rates of pedicle screw misplacement and minimal complications reported. Summary of Background Data. The main deterrent for the use of thoracic pedicular screws is the feared neurovascular complications due to screw “misplacements.” The literature shows that only a small fraction of the misplaced screws actually causes any complication, and some misplacements can be acceptable both in terms of safety and their biomechanical strength. Methods. Sixty patients with various spinal disorders were included in the study. The mean age was 29.6 years (range, 12–72 years). The patients were divided into 2 groups for assessment of pedicle screw placements using postoperative computed tomography scans: scoliosis group with 24 patients and the nonscoliosis group with 34 patients. Placements of screws were assessed using the outcome-based classification and the Rongming Xu criteria of screw placement. Results. A total of 341 screws were assessed from 60 patients with various spinal disorders (scoliosis and nonscoliosis groups). Using the Rongming Xu criteria, the overall screw misplacement in scoliosis group was 50.72% (68 of 138) and that in nonscoliosis group was 45.45% (80 of 176 screws). Assessment of these screws using the outcome-based classification showed a high percentage of acceptable screw placements (type 1) − 89.85% (124 of 138 screws) in the scoliosis group and 86.93% (153 of 176 screws) in the nonscoliosis group. Conclusion. The literature shows consensus over high rates of pedicle screw misplacement, but low clinical complications, in the hands of the best of spine surgeons. The concept of acceptable screw placements and the outcome classification makes the pedicle screw assessment results correlate better with the clinical outcome.

Microendoscopic versus Open Discectomy for Lumbar Disc Herniation: A Prospective Randomised Study

Purpose. To compare the outcomes of microendoscopic discectomy (MED) versus open discectomy for lumbar disc herniation. Methods. 80 men and 32 women aged 26 to 57 (mean, 37) years with a single-level disc herniation were randomised to undergo MED (n=55) or open (fenestration/laminotomy) discectomy (n=57). Patients were assessed pre- and post-operatively (at week 6, month 6, and year one). The 2 groups were compared with respect to surgical time, anaesthesia time, duration of hospital stay, intra-operative blood loss, weight of disc material removed, and self-evaluated low back pain and functional outcome (using the Oswestry low back pain disability questionnaire). Results. Surgical and anaesthesia times were significantly longer, but blood loss and hospital stay were significantly reduced in patients having MED than open discectomy. The improvement in the Oswestry score in both groups was significant at week one, but not at other follow-ups. The complication rate was similar in both groups. One patient with MED had a recurrence of disc herniation after 7 months and was treated with open discectomy. Conclusions. Both methods are equally effective in relieving radicular pain. MED entailed shorter hospital stay, less morbidity, and earlier return to work. Nonetheless, it is a demanding technique and should not be attempted without specific instruction and training.

Anterior versus posterior procedure for surgical treatment of thoracolumbar tuberculosis: A retrospective analysis.

Background: Approach for surgical treatment of thoracolumbar tuberculosis has been controversial. The aim of present study is to compare the clinical, radiological and functional outcome of anterior versus posterior debridement and spinal fixation for the surgical treatment of thoracic and thoracolumbar tuberculosis. Materials and Methods: 70 patients with spinal tuberculosis treated surgically between Jan 2001 and Dec 2006 were included in the study. Thirty four patients (group I) with mean age 34.9 years underwent anterior debridement, decompression and instrumentation by anterior transthoracic, transpleural and/or retroperitoneal diaphragm cutting approach. Thirty six patients (group II) with mean age of 33.6 years were operated by posterolateral (extracavitary) decompression and posterior instrumentation. Various parameters like blood loss, surgical time, levels of instrumentation, neurological recovery, and kyphosis improvement were compared. Fusion assessment was done as per Bridwell criteria. Functional outcome was assessed using Prolo scale. Mean followup was 26 months. Results: Mean surgical time in group I was 5 h 10 min versus 4 h 50 min in group II (P>0.05). Average blood loss in group I was 900 ml compared to 1100 ml in group II (P>0.05). In group I, the percentage immediate correction in kyphosis was 52.27% versus 72.80% in group II. Satisfactory bony fusion (grades I and II) was seen in 100% patients in group I versus 97.22% in group II. Three patients in group I needed prolonged immediate postoperative ICU support compared to one in group II. Injury to lung parenchyma was seen in one patient in group I while the anterior procedure had to be abandoned in one case due to pleural adhesions. Functional outcome (Prolo scale) in group II was good in 94.4% patients compared to 88.23% patients in group I. Conclusion: Though the anterior approach is an equally good method for debridement and stabilization, kyphus correction is better with posterior instrumentation and the posterior approach is associated with less morbidity and complications.

Video-assisted thoracoscopic anterior surgery for tuberculous spondylitis.

In the absence of major deformity, the major goal of surgery in tuberculous spondylitis is to achieve adequate cord decompression and débridement of diseased tissue. We asked whether video-assisted thoracoscopic surgery (VATS) could be undertaken in active tuberculosis of the spine with instrumentation and achieve good healing of the disease with fusion and with adequate decompression of the cord to achieve neural recovery. We retrospectively reviewed 23 patients (13 men and 10 women with an average age of 38.2 years) with single-level thoracic spinal tuberculosis (T4-T11) treated with VATS. Of the 23 patients, 18 had paraparesis/paraplegia. The procedures included: (1) débridement and drainage of prevertebral and paravertebral abscess (n = 4); (2) débridement, decompression, and reconstruction with rib graft (n = 8); (3) débridement, decompression, anterior vertical titanium mesh cage, and open posterior screw-rod fixation (n = 5); and (4) débridement, decompression, and anterior screw-rod fixation (n = 6). Twenty-two of 23 patients achieved fusion and there was no recurrence of the disease in any of the patients. No patient had neurological deterioration and 17 of the 18 neurologically compromised patients regained ambulatory power. Small scars (for surgical portals), early mobilization, and short hospital stays were the salient advantages.Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Fracture dislocation of the spine after total hip arthroplasty in a patient with ankylosing spondylitis with early pseudoarthrosis

BACKGROUND CONTEXT There are no studies suggesting the management of asymptomatic, early pseudoarthrosis with advanced hip and spine deformities in patients with ankylosing spondylitis. Literature advocates the correction of the hip deformity first and that of spine later. PURPOSE To highlight the importance of asymptomatic, early pseudoarthrosis lesion in a patient of ankylosing spondylitis with advanced hip and spine deformities. STUDY SETTING A 25-year-old female patient suffering from ankylosing spondylitis with 70 degrees of flexion deformity at right hip and rounded kyphosis of thoracolumbar spine was admitted for right total hip arthroplasty. METHODS Cementless total hip arthroplasty and flexor tendon release were performed on right hip under general anesthesia and patient was nursed in supine position postoperatively. RESULTS The patient developed cauda equina syndrome and loss of sensation below twelfth thoracic segment on the second postoperative day. Radiological evaluation showed a fracture dislocation of the second and third lumbar vertebrae. Retrospective re-examination of preoperative radiographs showed small erosion of the anteroinferior margin of the second lumbar vertebra. Patients neurological status did not improve after decompression and posterior stabilization of fractured spine. CONCLUSION Careful evaluation of the spine in patients with spondyloarthropathy with advanced hip and spine deformities should be done. Any lesion that can potentially destabilize the spine should be treated first before correcting hip deformity.

Smaller Interval Distractions May Reduce Chances of Growth Rod Breakage Without Impeding Desired Spinal Growth: A Finite Element Study

BACKGROUND Growth rods allow regular distraction of the spine to compensate for growth. Traditionally such distractions are performed every 6 months via open surgery. However with the advent of minimally invasive techniques like magnetically controlled growing rods, the distractions can be performed non-surgically. This also implies that the interval of distraction could be changed or customized based on individual patients need. HYPOTHESIS In this study we have hypothesized that the distraction at shorter intervals reduces the stresses on the rods which in turn reduces the chance of rod failure. OBJECTIVE A finite element model of a juvenile spine was instrumented with growth rods and distractions were applied at different frequencies (2 months, 3 months, 6 months, and 12 months) for a period of two years to study the effects of frequency of distraction on maximum von Mises stresses on the rods for different loading conditions were studied. RESULTS The stresses on the rods were highest for 12-month distraction (2 distractions in 2 years) and lowest for 2-months distraction (12 distractions in 2 years). CONCLUSION It was found that the shorter intervals of distraction led to reduction of stresses on the rod for same spinal height gain in two years.

Aneurysmal bone cyst in the metacarpal of a child: A case report

An unusual case of aneurysmal bone cyst in the metacarpal of a five-year-old girl is described. The lesion was initially diagnosed and treated as a simple bone cyst. Subsequently the affected metacarpal was excised and replaced by an autogenous fibular graft, with good results. A discussion of the pathogenesis of the lesion is given, with a review of the literature.

Distraction magnitude and frequency affects the outcome in juvenile idiopathic patients with growth rods: finite element study using a representative scoliotic spine model

BACKGROUND CONTEXT Growth rods are used to limit the progression of scoliosis without restraining the opportunity for the spine to grow. However, major complications like rod breakage, screw loosening, and altered sagittal contour have been encountered. OBJECTIVE To analyse the effect of the magnitude of distraction forces on the T1-S1 growth, maximum von Mises stresses on the rods, sagittal contours, and load at the pedicle screw-bone interface and quantify the maximum stresses on the rod for a period of 24 months using different frequencies of distraction in a representative scoliotic spine model. STUDY DESIGN A representative finite element model of a juvenile scoliotic spine was used to study the effect of magnitude and frequency of distraction on growth rods. METHODS A representative scoliotic model was developed and instrumented using proximal foundation, distal foundation, and rods. Part 1: simulation steps comprised 6 months of growth under various distraction forces to analyze effects of distraction force on the biomechanics of the spine and instrument. Part 2: simulation steps comprised 24 months of growth under various intervals of distraction to analyze effects of distraction interval on the propensity of rod fracture. RESULTS Part 1: an optimal distraction force exists for which the growth is sustained with minimum stress on the rod, lower loads at screw-bone interface, and unaltered sagittal contours. Part 2: the stresses on the rods were highest for 12-month distraction (2 distractions in 2 years) and lowest for 2-month distraction (12 distractions in 2 years). CONCLUSIONS The data and trend suggest that as the distraction forces vary so do the effects on spinal growth. The results of this study also signify the importance of shorter distraction period in reducing the stresses on the rods.

Pedicle morphometry in patients with adolescent idiopathic scoliosis.

Background: The key to the safe and effective use of thoracic pedicle screws in the deformed spine is to thoroughly understand pedicle anatomy. There are a few studies related to pedicle anatomy in the Indian population and no pedicle morphometric studies in scoliosis patients. The present study aims to highlight the differential features of pedicle morphometry, including pedicle width, transverse pedicle angle and the depth to anterior cortex on the concave and convex side, in a group of Indian patients with adolescent idiopathic scoliosis and compare this to that of a western population. Materials and Methods: This is a prospective study of 24 patients with adolescent idiopathic scoliosis. The average age is 14.6 years (12.3-18.3 years) of which 14 were females and 10 were males. All the patients underwent CT scan using Siemens 4th generation scanner. The scans were analyzed by measuring the transverse pedicle width, transverse pedicle angle and the chord length; all the measurements being made both on the convex as well as the concave pedicle. Statistical analysis was performed with unpaired ‘t’ test. Results: A total of 1295 measurements were performed from 24 patients and an average of 215 pedicles were assessed for each set of the measurements made. The transverse pedicle width was consistently found to be smaller on concave side in comparison with the convex side at all levels except at T1. The transverse pedicle angle was greater on the concave side at all levels as compared to the convex side, though there was wide individual variation. The depth to anterior cortex was lesser on convex side in comparison to the concave side except at T1. Conclusions: The concave pedicle is much thinner and directed more medially than the convex side, especially at the apical region of the scoliotic curve. The pedicle anatomy in scoliosis patients shows very high individual variations and a careful study of pre-operative CT scans is essential for planning proper pedicle screw placement. Slightly longer screws can be accommodated on the concave side as compared to the convex side, though the difference in the chord length is not statistically significant at most levels.