A 14-year-old boy was presented in outpatient department with severe kyphotic deformity of the thoracic spine and complete loss of power of both lower limbs. The patient had a history of a progressively increasing kyphotic deformity since the age of 4 years, almost 4-5 months back, he started developing weakness of both legs.
On physical examination, bossing of the thoracic cage was observed with short abdomen and both iliac crest almost touching the ribs [Figure 1a]. There was a prominent kyphotic hump at the thoracic level, the lower extremities had 0/5 power bilaterally along with spasticity. Reflexes of knees and ankles were exaggerated and Babinski sign was positive. Flexion contracture of 40  was observed in both knees.
Radiographic picture of spine showed severe kyphosis of 141  from T1 to T10 thoracic vertebrae on lateral view with diffuse paraspinal calcifications, most likely representing a granulomatous lesion [Figure1b]. MRI revealed acute angle kyphotic deformity appreciated at the upper-mid dorsal spine due to multiple deshaped dorsal vertebrae (starting from T1 down till T10), resulting in significant canal narrowing posteriorly with cord compression and compressive myelopathic changes. Abnormal marrow signals were appreciated in vertebrae with pathological reduction in their heights, with indistinct/eroded adjacent end plates and involved intervening discs, suggesting squeal of chronic disco vertebral osteomyelitis (caries spine).
Pathological necrotic tissue was also appreciated in pre- and paravertebral spaces at the affected levels. Similarly, variable sized paraspinal collections were identified with areas of low-intensity signals/signal void suggested chronic calcified component [Figure 2]. Blood work-up was within normal limits.
Distraction using a modified halo-pelvic distraction assembly was planned to stretch out the soft tissues aiming to decrease the severity of the deformity and compression on the spinal cord and to improve the neurology.
Pelvic ring was substituted with two lateral arches which allowed the patient to lie supine in bed.
Supra-acetabular region was chosen for half pin placement which provided a sturdy anchorage and gave a strong construct.
Muscles were not pierced for the placement of wires or pins that minimized the risk of infection and pain.
The assembly construct had four rods, two of them were placed anterolateral and the other two were posterolateral. The aim was to provide balanced distraction forces so that the sagittal or coronal balance should not be affected.
An assembly was prepared with the following modifications: 
A halo ring according to the head size was chosen and connected to the head with 06 threaded pins.
A total of four Ilizarov half pins were used in the pelvic assembly. Two Ilizarov half pins of 6 mm each were passed in the supra acetabular area one on both sides. Anterior inferior iliac spine was approached through blunt dissection after giving a 2 cm incision, almost 2 cm below and medial to the anterior superior iliac spine (ASIS) on both sides. The outer cortex at anterior inferior iliac spine was drilled with a 4 mm drill bit and a 6 mm half pin was passed using a T handle.
The 2nd site for half pin placement was about 10 cm posterior to the ASIS. After making a small incision, the outer cortex was drilled and a 6 mm half pin was passed in between the inner and outer tables of the iliac bone on both sides using a T handle. Both half pins on either side were connected to an Ilizarov arch using male posts and rancho cubes. Both arches were connected with each other through two threaded rods to strengthen the construct [Figure 3].
Distraction device consisted of four threaded rods, two anterolateral and two posterolateral connecting pelvic assembly to the halo assembly.
Distraction was started on the 1st postoperative day at the rate of 3 mm per day divided in three intervals of 1 mm each. On the 5th postoperative day, the patient started to move his right foot and started to feel touch sensations in his right leg. Distraction was continued at this constant pace of 3 mm per day for 35 days. The patient was closely monitored for his progress by getting weekly X-rays of the spine and measuring the trunk height and kyphotic angle.
After 35 days of distraction, rib hump and thoracic knuckle markedly improved and Cobb angle reduced from 141  to 56  [Figure 4] and the patient height increased up to 8 cm. Power of the legs improved to 2/5 bilaterally.
At this time, resection of vertebral bodies, thorough debridement and stabilization using a vertebral standalone cage through anterior approach, was planned and surgery was performed by the senior author (AA). A cage was placed from T1 to T10 vertebral body after debridement [Figure 5]. After the definitive surgery, kyphotic angle was reduced to 46 .
GeneXpert analysis of the tissue revealed multidrug-resistant tuberculosis. Postoperatively, the patient is doing well and put on 2nd line antituberculous therapy.