1. Spinal Infections Himanshu Sharma

2. Spinal Infections Objectives Epidemiology Pathology Clinical features Management Prognosis

3. Spinal Infections Epidemiology 2 - 4% all cases of “osteomyelitis” Rare: 1 in 250,000/yr but rising incidence Post-op discitis = 2-3% Pre-antibiotic mortality = 25-70% Delayed diagnosis common (50%+ > 3/12)

4. Spinal Infections Levels Spondylodiscitis / facet disease Lumbar(59%) Thoracic(33%) Cervical(8%) Epidural abscess (in 7%) Cervical(6-18%) anterior Thoracic Lumbar

5. Spinal Infections Risk Factors Peak incidence 7th decade Concurrent illness/infection DiabetesObesity Immunosuppressed Malnutrition Steroid therapyIrradiation UTI Invasive procedures/ trauma Smoking

6. Spinal Infections Pathology (1) Organisms S aureus 30 -50% cases Gram-negatives – UTI, Chest, Skin ulcers Opportunistic in immune paresis IVDA Route of spread Haematogenous Direct extension Post-operative

7. Spinal Infections Pathology (2) Vertebral metaphyses (end plate region) =end-arteriole blood supply (filter)  Septic emboli Direct spread from implantation  Secondary spread to discs, paraspinal tissues and spaces

8. Spinal Infections Clinical Features Pain and focal tenderness90% Fever61% Root symptoms/signs60% Abnormal neurology20% Also: deformity, muscle spasms, meningism, sinus, and unexplained septicaemia

9. Investigations FBC ESR CRP Blood & Urine cultures Nutritional status Biopsy

10. Spinal Infections Diagnosis Lab tests  White cell count40-50%  ESR / CRP80-90% Positive Blood Culture20-25% Imaging Biopsy

11. Spinal Infections Plain radiological findings Vertebral metaphyseal blurring (osteolysis) Loss of disc height Endplate blurring Subchondral reactive bone formation Bone destruction (and deformity) Soft-tissue shadows e.g.psoas abscess

12. Pyogenic discitis/osteomyelitis Bad disc = Good news

13. Spinal Infections Imaging Studies - Isotopes Detect earlier than plain films High sensitivity / specificity e.g. gallium + Tc = 95% accurate Little structural information False negatives in neutropenics (gallium) False negatives in bone infarction (Tc)

14. Pyogenic spinal infections imaging studies - CT delineate bony margins / involvement soft-tissue invasion poor for outlining neural elements risk of spread if combine with myelography, but can obtain CSF 3D/MPR useful for pre-op planning of reconstruction

15. Spinal Infections Differential Diagnosis Granulomatous disease Metastases/Myeloma Degenerative disease Osteoporosis Local Scheuermann’s Spondyloarthropathies

16. T1=  signalT2=  signal Ring enhancement > 95% accuracy

17. Spinal Infections Biopsy Biopsy (for identification of the causative organism) Closed needle biopsy (guided) –68 - 86% accuracy (false negative 30%) Open biopsy –> 80% accurate (false negative 14%) Special lab techniques (DNA PCR, etc)

18. Biopsy principles Biopsy material should be sent to microbiology for gram stain & acid-fast stain, aerobic, anaerobic, fungal and mycobacterial cultures and for histopathological examination.

23. Spinal Infections Treatment Goals Establish diagnosis Clear infection and prevent recurrence Pain relief Protect / restore neurological function Maintain / restore spine stability

24. Changed Battlefield Territory –Patients Weapons –Antibiotics –Surgery Enemy –Microbiology

25. Territory - changed Patient Population Greying Type 2 DM Cancer Steroids HIV Drug Abuse Iatrogenic Immunosuppression Transplants Dialysis

26. Enemy - changed More Resistant Strains of Bacteria Hospital Acquired Infection More previously unsuspected causes

27. Weapons - Antimicrobials Type and Scope of Surgery

28. Why is it important? Consequence of Inappropriate Management Multiple Surgery Pain Paralysis Death Financial Cost Causes of Inappropriate Management Lack of awareness Empirical Antibiotics Inappropriate /Inadequate Surgery

29. Spinal Infections Treatment (1) Antibiotics –sensitivities –adequate dose (iv then oral) –ensure MBC reached –adequate duration (> 6 weeks) –monitor response (clinical/ indices/ imaging) –toxicity profile and monitoring

30. Spinal Infections Treatment (2) Immobilisation –bed rest –moulded orthoses (low thoracic / lumbar) –halo-vest or orthosis (cervical / high thoracic)

31. 9/12

32. Pyogenic spinal infections