Surgical management of Pott's disease of the spine in pediatric patients: A single surgeon's experience of 8 years in a tertiary care center

Pathogenesis, Diagnostic Challenges, and Risk Factors of Pott's Disease

Tuberculosis (TB) prevalence is increasing in developed nations and continuing to cause significant mortality in low- and middle-income countries. As a result of the uptick in cases, there also exists an increased prevalence of extrapulmonary TB. TB is caused by Mycobacterium tuberculosis (M. tb). When M. tb disseminates to the vertebral column, it is called Pott's disease or spinal TB. The frequency, symptoms, and severity of the disease range by the location of the spine and the region of the affected vertebrae. While the current literature shows that timely diagnosis is crucial to reduce the morbidity and mortality from Pott's disease, there is a lack of specific clinical diagnostic criteria for Pott's disease, and the symptoms may be very non-specific. Studies have shown that novel molecular diagnostic methods are effective and timely choices. Research has implicated the risk factors for the susceptibility and severity of Pott's disease, such as HIV and immunosuppression, poverty, and malnutrition. Based on the current literature available, our group aims to summarize the pathogenesis, clinical features, diagnostic challenges, as well as the known risk factors for Pott's disease within this literature review.

Severe Pott's Kyphosis in a 19-Month-Old Child: Case Report and Review of Literature

BACKGROUND

Spinal osseous tuberculosis, or Pott's spine, although very common in endemic countries, has a lower incidence in very young children. However, the infection has the propensity to cause greater vertebral destruction in this age group, leading to severe structural kyphotic deformity and associated neurologic deficits. We report the case of a 19-month-old child with severe tubercular kyphotic deformity of the upper thoracic spine managed with posterior vertebral column resection (VCR) and nonfusion posterior pedicle screw instrumentation.

CASE DESCRIPTION

This 19-month-old boy presented with 1-month history of spontaneous-onset, progressive, painful rigid kyphotic deformity of the upper back associated with spastic paraparesis with bowel and bladder incontinence. Magnetic resonance imaging showed severe destruction of bodies of D4-D7 vertebrae with cord edema and draping of the spinal cord over the internal gibbus at D4-D7. Surgery was performed with a restricted anterior fusion via single-stage posterior VCR at D4-D7 with nonfusion pedicle screw instrumentation from D1 to D9, with subsequent extension of instrumentation to D10 after 4 months.

CONCLUSIONS

Multilevel posterior VCR with a restricted fusion and nonfusion pedicle screw instrumentation beyond the resection site can be safely done in young children (age <3 years) requiring rigid tubercular kyphotic deformity correction. However, these patients require regular follow-up and may need multiple surgeries.

The spectrum of tuberculosis of the spine in pediatric age group: a review

INTRODUCTION

Pediatric spinal tuberculosis is characterized by rapid bone destruction and carries the risk of rapid onset neurological deficits and severe deformity of the spine. Behavior of spinal deformity over time is affected by growth of spine. Owing to this dynamic behavior of pediatric spinal tuberculosis both in active phase and in healed phase, it presents with challenges which are quite different from adults with caries spine. A clinician must have high index of suspicion for accurate and early diagnosis of spinal tuberculosis in the pediatric population and should also have a thorough knowledge of differences in natural history between adult and pediatric spinal tuberculosis.

DISCUSSION

This is based on the senior author's experience of dealing with tuberculosis of the spine in children over the last two decades. Recent advances in field of rapid diagnosis of tuberculosis based on nuclear material-related diagnostic tests have further improved the management of tuberculosis. At the same time, the basic treatment principles remain the same. However, the threshold for surgical vs conservative treatment have subtle differences when compared to adult population. The importance of long-term follow-up after treatment must be appreciated.

CONCLUSION

Tuberculosis in the spine in children needs early attention. Prompting to diagnostic and medical therapy measures can avoid neurological sequellae and delayed deformity.

Early diagnosis of spinal tuberculosis

Spinal tuberculosis (STB) is a common manifestation of extrapulmonary tuberculosis (TB). STB accounts for around 2% of all cases of TB and around 15% of extrapulmonary TB cases. The World Health Organization has proposed a global strategy and targets for TB prevention, care, and control after 2015. Under this strategy, patients will receive standard care according to the recommendations and guidelines after confirmation of STB diagnosis. However, current recommendations and guidelines focus on disease and medication therapy management, and recommendations for early detection or decision-making algorithms regarding STB are lacking. In this review, we identified five key components for early diagnosis: (1) risk factors for STB; (2) common symptoms/signs of STB; (3) significant neuroradiological findings of STB; (4) significant laboratory findings of STB, including positive interferon-γ release assays and nonpyogenic evidence in initial laboratory data; and (5) significant clinical findings of STB. Individualized consideration for each patient with STB is essential, and we hope that the algorithm established in this review will provide a valuable tool for physicians who encounter cases of STB.

Pediatric iatrogenic thoracic kyphosis and tension myelopathy treated with a thoracic pedicle subtraction osteotomy: a case report and review of the literature

PURPOSE

Pediatric kyphotic deformity is an uncommon clinical entity that can occur following posterior spinal operations and has significant complexity in its treatment. Tension myelopathy in a pediatric patient with a thoracic kyphotic deformity has not been reported in the literature.

CASE REPORT

We present a 17-year-old boy with a progressive thoracic kyphosis and tension myelopathy 4 years after he underwent a thoracic laminoplasty at an outside institution for the treatment of a dorsal spinal arachnoid cyst. At our institution, he was treated with a pedicle subtraction osteotomy as well as thoracic Ponte osteotomies for sagittal plane correction to relieve the tension myelopathy.

CONCLUSIONS

Both clinical and radiographic improvements were observed after surgery. We review the literature on pediatric thoracic kyphosis and tension myelopathy and the treatment of these pathologies.

Pott's Spine: Diagnostic Imaging Modalities and Technology Advancements

Spinal tuberculosis (TB) or Pott's spine is the commonest extrapulmonary manifestation of TB. It spreads through hematogenous route. Clinically, it presents with constitutional symptoms, back pain, tenderness, paraplegia or paraparesis, and kyphotic or scoliotic deformities. Pott's spine accounts for 2% of all cases of TB, 15% of extrapulmonary, and 50% of skeletal TB. The paradiscal, central, anterior subligamentous, and neural arch are the common vertebral lesions. Thoracic vertebrae are commonly affected followed by lumbar and cervical vertebrae. Plain radiographs are usually the initial investigation in spinal TB. For a radiolucent lesion to be apparent on a plain radiograph there should be 30% of bone mineral loss. Computed tomographic scanning provides much better bony detail of irregular lytic lesions, sclerosis, disc collapse, and disruption of bone circumference than plain radiograph. Magnetic resonance imaging (MRI) is the best diagnostic modality for Pott's spine and is more sensitive than other modalities. MRI frequently demonstrates disc collapse/destruction, cold abscess, vertebral wedging/collapse, marrow edema, and spinal deformities. Ultrasound and computed tomographic guided needle aspiration or biopsy is the technique for early histopathological diagnosis. Recently, the coexistence of human immunodeficiency virus infections and TB has been increased globally. In recent years, diffusion-weighted MRI (DW-MRI) and apparent diffusion coefficient values in combination with MRI are used to some extent in the diagnosis of spinal TB. We have reviewed related literature through internet. The terms searched on Google scholar and PubMed are TB, extrapulmonary TB, skeletal TB, spinal TB, Pott's spine, Pott's paraplegia, MRI, and computed tomography (CT).

Evaluation of prognostic factors in medically treated patients of spinal tuberculosis

This study was aimed to determine the prognostic factors in medically treated patients of spinal tuberculosis. In this longitudinal observational study, from July 2010 to December 2011, 70 consecutive patients (40 males and 30 females) spinal tuberculosis were enrolled. Diagnosis of spinal tuberculosis was based on characteristic clinical and neuroimaging features. Diagnosis was histopathologically and/or bacteriologically verified. Patients received antituberculous treatment as per World Health Organization guidelines and were followed for 6 months. Disability was evaluated with modified Barthel index (MBI). Outcome was defined as good (MBI > 12) and poor (MBI ≤ 12). Various clinical and neuroimaging parameters, likely to affect the outcome, were analyzed using univariate and multivariate analysis. After 6 months, 45 patients had a good outcome, while 25 patients had a poor outcome. On univariate analysis, duration of illness >6 months (OR 0.062, CI 0.018-0.212), bladder involvement (OR 0.102, CI 0.033-0.317), spinal deformity (OR 0.050, CI 0.013-0.196), spastic paraparesis (OR 0.572, CI 0.190-1.723), and flexor spasms (OR 0.077, CI 0.021-0.280) were found as important clinical predictors of poor outcome. Involvement of more than 2 vertebrae (OR 0.095, CI 0.028-0.328), complete collapse (OR 0.072, CI 0.022-0.241), cord compression (OR 0.025, CI 0.003-0.204), spinal extension of the abscess (OR 0.044, CI 0.005-0.350), and thick/septate abscess wall (OR 0.062, CI 0.016-0.240) were the neuroimaging parameters associated with poor prognosis. However, on multivariate analysis, duration of illness >6 months (Exp-b 0.086, CI 0.019-0.378), cord compression (Exp-b 0.035, CI 0.003-0348), and spinal extension of the abscess (Exp-b 0.109, CI 0.017-0.91) were significant. Medical management results in clinical improvement in a majority of the patients of spinal tuberculosis. Duration of illness >6 months, cord compression, and spinal extension of abscess are associated with poor outcome.

Pediatric cranio-vertebral junction tuberculosis: management and outcome

INTRODUCTION

Tuberculosis (TB) of the cranio-vertebral junction (CVJ) is a rare condition, accounting for 0.3 % to 1 % of all cases of spinal TB. Early diagnosis and treatment are important in preventing long-term neurological sequelae. Management protocol of this rare site of TB is yet to be conclusively established. This holds particularly true for pediatric age group in which this condition is infrequently encountered.

MATERIALS AND METHODS

A total of 29 consecutive pediatric patients presented to the Department of Neurosurgery at Sanjay Gandhi Post-Graduate Institute of Medical Sciences, Lucknow, from January 1997 to October2011 with clinical and/or radiological features suggestive of CVJ TB. A clinical grading system to evaluate the neurological status was developed, and all patients were evaluated using this scoring system. Patients were radiologically evaluated with computed tomography (CT) of CVJ and magnetic resonance imaging (MRI) with gadolinium enhancement. These cases were managed according to their grade and followed up.

RESULTS

Out of a total of 29 cases, 18 were females and 11 males. Age range was 4 to 18 years with mean age 9 ± 3.8 years. The follow-up period ranged from 2 months to 7.5 years with mean follow-up of 2.7 years. Eleven cases were of grades 1 and 2, and 18 cases were of higher grade (grades 3 and 4). Predominantly conservative approach was utilized in cases with better clinical status, and grade (grades 1 and 2) and surgical intervention was needed in the more severe grades. All cases had significant improvement at the last follow-up.

CONCLUSION

One needs to have a high index of suspicion of CVJ TB if one encounters a case with neck pain, neck restriction, and raised erythrocyte sedimentation rate. CT CVJ and MRI with gadolinium contrast enhancement are the investigations of choice for both establishing a diagnosis and planning the management. For cases with mild neurological deficit, conservative approach would work for majority of cases, and for severe cases, initial conservative approach may be tried, failing which surgical intervention would be needed.

Round and angular kyphosis in paediatric patients

Structural kyphosis is a posterior convex deformity of the spine that may appear in childhood then worsen with growth, most notably during the pubertal growth spurt. The abnormal curvature may be smooth, defining round kyphosis, or may display a sharp angular pattern. Angular kyphosis is the more severe of the two forms. The main causes of round kyphosis are postural kyphosis and Scheuermann's disease. The spontaneous outcome is favourable, and round kyphosis is well tolerated in adulthood. The treatment relies on orthopaedic methods in the overwhelming majority of cases. Surgery is reserved for severe rigid kyphosis in older children and for kyphosis responsible for refractory pain or neurological deficits. Surgical treatment carries a non-negligible risk of neurological, gastrointestinal, mechanical, and septic complications, which should be explained clearly to the family. Advances in contemporary posterior instrumentation have considerably limited the indications for anterior approaches. Many conditions may cause angular kyphosis, whose greater severity is related to a greater potential for progression and neurological impairment. Clinical investigations are in order to identify the cause and to plan the surgical strategy. Early surgery may be indicated, via a combined anterior and posterior approach. Anterior strut grafting, anterior or posterior osteotomies, or even vertebral column resections may be necessary to correct a major deformity.