Presentation
Thoracic spine discitis/osteomyelitis.
Patient Data
Disc access was achieved via the costovertebral joint, using an 18-gauge Quincke needle under biplane fluoroscopy. However, no aspirate could be obtained.
A transpedicular approach was planned to access the disc and endplates for biopsy. Local anesthetic was given along the needle track with a 23 gauge needle, and then a 22 gauge Quinkce needle. The latter helping plan the angulation for the bone biopsy trocar. The 14 gauge trocar accessed the pedicle, and the inner trocar was removed once the tip was just below the inferior endplate. The biopsy trocar was then inserted and an adequate sample obtained.
T9/T10 discitis/osteomyelitis with surrounding enhancing paraspinal phelgmon and epidural abscess, not causing significant canal narrowing. Associated right lower lobe consolidation and bilateral pleural effusions.
Case Discussion
Discitis/osteomyelitis should be considered in all pyrexial patients and back pain. MRI is the primary imaging modality of choice, which should assess the level affected, amount of adjacent phlegmon/abscess, epidural collection, and central canal narrowing.
Biopsy/aspiration should be reserved for those with negative blood cultures and those who are not responding to first-line antibiotics. A large meta-analysis showed yields vary widely, with radiological-guided biopsy found to have a yield of around 48%, compared with 76% with open surgical biopsy. Yields were 32% in those with prior antibiotic exposure, 43% without, which was not significantly different 1.
Biopsy can be performed under both fluoroscopy and CT fluoroscopy.