a summary of adult Pyogenic spine infections. references are listed.

1. Adult Pyogenic Vertebral
Osteomyelitis
Robert Oluoch (Mmed. Otho. Surg)

3. • Introduction
• Vertebral osteomyelitis, also known as spondylodiskitis
• Epidemiology
• Demographics: usually seen in adults (median age for pyogenic osteomyelitis
is 50 to 60 years)
• Location: 50-60% of cases lumbar spine; 30-40% thoracic spine; 10% in
cervical spine 2
• M˃F 2:1
• France – annual incidence of spondylodiscitis of 2.4 per 100,000
person-years; almost triples for ages older than 70 years 1
1. Kourbeti IS, Tsiodras S, Boumpas DT. Spinal infections: evolving concepts. Curr Opin Rheumatol
2008;20(4):471—9.
2. Wisneski RJ. Infectious disease of the spine. Diagnostic and treatment considerations. Orthop Clin North
Am 1991;22(3):491—501.

4. • Risk factors:
• IV drug abuse
• diabetes
• recent systemic infection (UTI, pneumonia)
• obesity
• malignancy
• immunodeficiency or immunosuppressive medications
• malnutrition (serum albumin < 3 g/dL indicative of malnutrition)
• Trauma - In around 5% of patients, a history of blunt trauma to the spinal column can
be elicited.
• Smoking
• Approximately 37% of pyogenic spontaneous spondylodicitis will not have
an identifiable source 4
1. Govender S. Spinal infections. J Bone Joint Surg Br 2005;87(11):1454—8.
2. Hlavin ML, Kaminski HJ, Ross JS, Ganz E. Spinal epidural abscess: a ten-year perspective. Neurosurgery
1990;27(2):177—84.
3. Reihsaus E, Waldbaur H, Seeling W. Spinal epidural abscess: a meta-analysis of 915 patients. Neurosurg Rev
4. Lestini WF, Bell GR. Spinal infections: patient evaluation. Semin Spine Surg 1990;2:244—56. .
2000;23(4):175—204, discussion 205.

5. Sapico FL, Montgomerie JZ. Vertebral osteomyelitis. Infect
Dis Clin North Am 1990;4(3):539—50

6. • Pathophysiology
• Pathogens:
• staph aureus - most common (50-65%)
• staph epidermidis - second most common
• gram negative infections - increasing over last decade and often associated
with gram negative infections of the GU and respiratory tract
• Pseudomonas - seen in patients with IV drug use
• Salmonella - seen in patients with sickle cell disease

7. • neurologic involvement
• neurologic deficits present in 10-20% results from
• direct infectious involvement of neural elements
• compression from an epidural abscess
• compression from instability of the spine
• associated conditions / complications
• epidural abscess: defined as a collection of pus or inflammatory granulation
tissue between dura mater and surrounding adipose tissue
• usually associated with vertebral osteomyelitis: present in ~18% of patients
with spondylodiskitis
• 50% of patients with an epidural abscess will have neurologic symptoms

8. • Presentation
• History: history of UTI, pneumonia, skin infection, organ transplant are
common
• Sapico and Montgomerie: 50% of patients had symptoms lasting greater
than 3 months before diagnosis is established 1
• Symptoms
• fever is only present in 1/3 of patients
• Pain: pain is often severe and insidious in onset
• pain is usually worse with activity and unrelenting in nature
• pain that awakens patients at night should raise concern for malignancy and infection
• neurologic symptoms present in 10-20%
• Radiculopathy
• Myelopathy
• meningitis
• Physical exam: neurological exam
1. Sapico FL, Montgomerie JZ. Pyogenic vertebral osteomyelitis: report of nine cases and review of the
literature. Rev Infect Dis 1979;1(5):754—76.

9. • Studies
• Laboratory
• WBC: elevated only in ~ 50%
• not a sensitive indicator for early infection
• ESR: elevated in 90% of cases
• can be monitored serially to track success of treatment; considered less reliable than CRP
• CRP: elevated in 90% of cases
• can be monitored serially to track success of treatment and is considered more reliable
than ESR
• Rath et al. : CRP although nonspecific may be a more clinically
useful index than ESR; should be used to follow the course of the
disease 1
1. Rath SA, Neff U, Schneider O, Richter HP. Neurosurgical management of thoracic and lumbar vertebral
osteomyelitis and discitis in adults: a review of 43 consecutive surgically treated patients. Neurosurgery
1996;38(5):926—33.

10. • Blood cultures
• Helpful in guiding the choice of antimicrobial therapy.
• least invasive method to determine dx
• sensitivity & specificity ~33% (reports show 25%-66%) of patients with
spondylodiskitis have positive blood cultures
• when positive 85% are accurate for isolating the correct organism
• blood culture yield: improved by withholding antibiotic and obtaining
cultures when patient is febrile
• Urine and focal suppurative processes should be cultured.

11. • CT or fluoroscopy percutaneous guided biopsy
• Indications: patients who do not have indications for immediate open surgery
and blood cultures are negative
• sensitivity & specificity can provide diagnosis in 68-86% of patients
• cultures should be sent for aerobic, anaerobic, fungal, acid-fast cultures
• Open biopsy
• indications : when tissue/organism diagnosis can not be made with
noninvasive techniques
• technique : anterior, costotransversectomy, or transpedicular approach used
• Razak et al. : accuracy of 93.3% in open biopsy techniques 1
1. Razak M, Kamari ZH, Roohi S. Spinal infection—–an overview and the results of treatment. Med J Malaysia
2000;55(Suppl.C):18—28.

12. • Imaging
• Radiographs
• findings delayed by weeks (3-6) 1
• findings include
• 1st radiographic sign of infection: irregularity of
vertebral end-plate of the infected level
• paraspinous soft tissue swelling (loss of psoas shadow)
seen in first few days
• disc space narrowing and disc destruction seen at 7-10
days
• disc destruction is atypical of neoplasm
• endplate erosion or sclerosis seen at 10-21 days
• local osteopenia
1. Waldvogel FA, Papageorgiou PS. Osteomyelitis: the past
decade. N Engl J Med 1980;303(7):360—70.

13. • CT: shows bony abnormalities, abscess formation, extent of bony
involvement, disc space narrowing; for surgical planning
• MRI: MRI with gadolinium contrast
• gold standard for diagnosis and treatment
• sensitivity and specificity: most sensitive (96%) and specific (93%)
imaging modality for diagnosis of spinal osteomyelitis 1
• most specific imaging modality to differentiate from tumor
• findings include:
• paraspinal and epidural inflammation
• disc and endplate enhancement with gadolinium
• T2-weighted hyperintensity of the disk and endplate
• rim enhancing
1. Dagirmanjian A, Schils J, McHenry MC. MR imaging of spinal infections. Magn Reson Imaging Clin N Am
1999;7(3):525—38.

15. • Bone scan: Technetium Tc99m bone scans
• Indications: patients who can not obtain an MRI
• sensitivity and specificity: 90% sensitive but lack specificity
• combined Technetium Tc99m and gallium 67 scan is both more specific and
more sensitive than Technetium Tc99m alone
• indium 111 labeled scan: not recommended due to poor sensitivity
(17%)

16. • Differential diagnoses 1
• degenerative or metastatic spinal disease
• disc herniation
• Vertebral compression fracture
• Inflammatory spondyloarthropathies such as ankylosing spondylitis or
reactive arthritis
• Spinal Tumors: MRI is the most specific imaging modality to differentiate
from tumor
• features that weigh towards an infection include:
• disc space involvement
• end-plate erosion
• significant inflammation
• In general spinal infections involve the disc whereas neoplasms involve
the vertebrae and spare the disc.
1. Cottle L, Riordan T. Infectious spondylodiscitis. J Infect 2008;56(6):401—12.

18. • Treatment
• Nonoperative/conservative
• The principles of conservative treatment include:
(a) establishment of an accurate microbiological diagnosis
(b) treatment with appropriate antibiotics
(c) spinal immobilization
(d) careful monitoring for clinical and radiographic evidence of spinal instability
and progression of infection or neurological deterioration.
• Antibiotics: once organism has been identified via blood culture or
biopsy
• if patient is septic or critically ill then start broad spectrum antibiotics
immediately which include
• Vancomycin for pencicillin-resistant and gram-positive bacteria
• third-generation cephalosporin for gram-negative coverage

19. Incidence of treatment failure was higher when parenteral therapy was administered for less than 4 weeks:
REF - Eismont FJ, Bohlman HH, Soni PL, Goldberg VM, Freehafer AA. Pyogenic and fungal vertebral
osteomyelitis with paralysis.J Bone Joint Surg Am 1983;65(1):19—29.

20. • Operative
• The principles of surgical treatment
(a) thorough debridement and removal of infected tissue
(b) decompression of neural elements
(c) restoration of spinal alignment
(d) correction of spinal instability
• Indications:
• Failure to respond to conservative therapy
• Significant or progressive neurologic deficits
• Large paraspinal abscess with local mass effect or septic embolization
• Significant osseous disease with involvement of two adjacent vertebral
bodies, or greater than 50% loss in a single vertebral body
• Progressive deformity with or without incapacitating spinal pain

21. • Techniques: In general, only the anterior vertebral elements are
involved in infection
• Anterior debridement and strut grafting, +/- posterior
instrumentation
• Techniques: strut graft selection - autogenous tricortical iliac crest,
rib, or fibula strut grafts have proven safe and effective in presence of
acute infection
• allograft being used with good results, but autogenous sources theoretically
have better incorporation
• a recent study showed improved deformity correction with titanium mesh
cages filled with autograft (followed by posterior instrumentation)

22. • Instrumentation
• spinal instrumentation in presence of active infection is controversial
• some advocate I&D followed by staged instrumentation
• some advocate a single procedure with bone graft and instrumentation in the
presence of an active infection
• posterior instrumentation:
• indicated when severe kyphotic deformity or a multilevel anterior construct
required
• can be performed at same time or as a staged procedure