Physical Address

304 North Cardinal St.
Dorchester Center, MA 02124

Lumbar osteomyelitis and discitis


Introduction

The incidence of vertebral osteomyelitis is approximately 1 per 100,000 per year worldwide ; however, this incidence increases with age up to 6.5 per 100,000 among persons older than 70 years of age. Overall, vertebral infections represent 1% of all the skeletal infections. Staphylococcus aureus is the most common pathogen implicated. The primary route of spread is hematogenous, usually from the urinary tract. It primarily affects the vertebral bodies, with only a small percentage of cases affecting the posterior elements. Posterior elements infection is associated with advanced disease. The complete spectrum of pyogenic vertebral osteomyelitis comprises spondylitis, discitis, spondylodiscitis, osteomyelitis, and epidural abscesses. The most common presenting symptom is back pain, which is reported in 86% of the cases. Fever occurs in less than 50% of patients at presentation. The most common spinal segments affected are the lumbar vertebrae, followed by the thoracic and cervical spine. Most cases resolve with prolonged medical therapy (i.e., antibiotics); however, surgical intervention may be employed for patients who have progressive neurological deficits, failure of adequate conservative treatment, or intractable radicular pain from epidural extension of the infection. Delayed surgical treatment may be associated with higher rates of sepsis and impaired neurological status. Spinal instrumentation may or may not be used and depends on the stability of the affected spinal segments or the presence of deformity. Currently, there is a gap in the literature describing high levels of evidence for surgical versus nonsurgical intervention. Thus surgical indications and modalities are still controversial. Herein, we describe the case of a 60-year-old immunosuppressed woman who presented with nonspecific back pain and left dorsiflexion weakness and imaging concerning for lumbar osteomyelitis.

Example case

  • Chief complaint: back pain, weakness

  • History of present illness: A 60-year-old female patient with progressive back pain and left dorsiflexion weakness. She is immunosuppressed from a previous renal transplant and has no other constitutional symptoms. She also reports left greater than right leg pain when ambulating. The patient underwent a magnetic resonance ( Fig. 62.1 ) and a computed tomography of the lumbar spine ( Fig. 62.2 ) that showed the presence of vertebral osteomyelitis associated with discitis and ventral epidural collection.

    Fig. 62.1, Preoperative sagittal magnetic resonance image of the lumbar spine. (A) T2 sagittal image demonstrating high signal intensity in the disc space (suggestive of infectious fluid), L5 and S1 vertebral bodies (suggestive of marrow edema), and paraspinal soft tissue (suggestive of paraspinal infectious fluid or abscess). (B) T1 sagittal image demonstrating low signal intensity in the disc space, L5 and S1 vertebral bodies, and paraspinal soft tissue. (C) T1 postgadolinium image confirming L5-S1 spondylodiscitis with peripheral contrast enhancement around the disc space fluid collection. Additionally, it shows disc space narrowing and abnormal contrast enhancement of L5, S1, and paraspinal extension anteriorly and posteriorly resulting in a ventral epidural abscess.

    Fig. 62.2, Preoperative computed tomography scans. (A) Coronal and sagittal images demonstrating erosion of the caudal L5 and cranial S1 endplates and narrowing of the L4-5 disc space. (B) Sagittal and axial images demonstrating ventral epidural abscess causing moderate spinal canal stenosis and bilateral neuroforaminal stenosis.

  • Medications: immunosuppressants

  • Allergies: no known drug allergies

  • Past medical and surgical history: renal failure, immunosuppression, renal transplantation

  • Family history: none

  • Social history: none

  • Physical examination: awake, alert, and oriented to person, place, and time; cranial nerves II–XII intact; bilateral deltoids/triceps/biceps 5/5; interossei 5/5; iliopsoas/knee flexion/knee extension/plantar flexion 5/5; left dorsiflexion 4/5.

  • Reflexes: 2+ in bilateral biceps/triceps/brachioradialis with negative Hoffman; 2+ in bilateral patella/ankle; no clonus or Babinski; sensation intact to light touch

  • John H. Chi, MD, MPH

  • Neurosurgery

  • Brigham and Women’s Hospital

  • Boston, Massachusetts, United States

  • Luis Rodrigo Diaz Iniguez, MD

  • Orthopaedic Surgery

  • Hospital Angeles Lindavista

  • Mexico City, Mexico

  • Juan Fernando Ramon, MD

  • Neurosurgery

  • University Hospital Fundacion Santa Fe de Bogata

  • Bogota, Columbia

  • Anand Veeravagu, MD

  • Neurosurgery

  • Stanford University

  • Palo Alto, California, United States

Preoperative
Additional tests requested

  • Blood cultures

  • Interventional radiology for biopsy

  • L-spine x-ray

  • Infectious disease evaluation

  • CBC/ESR/CRP

  • Febrile antigen panel, BCG test

  • Infectious disease evaluation

  • CBC/ESR/CRP

Standing flexion-extension lumbar x-rays
Surgical approach selected If infection persistent after treatment and/or worsening symptoms, MIS L5-S1 TLIF and posterior percutaneous L4-5 fusion Lumbar wound incision and drainage and biopsy of L5-S1 disc space After antibiotics, L2-iliac posterior fusion L4-S1 (possible S2) decompression and fusion
Goal of surgery Decompression, stabilization, debridement of infection Drainage and washing, bacterial cultures, biopsy Stabilization Sample infection, debride L5-S1 level, stabilization
Perioperative
Positioning Prone Prone Prone Prone on Jackson table
Surgical equipment

  • Fluoroscopy

  • O-arm

  • Surgical navigation

  • Surgical microscope

Fluoroscopy

  • Fluoroscopy

  • O-arm

  • IOM (SSEP/MEP)

  • Surgical navigation

Medications Liposomal bupivacaine Hold antibiotics until sampling None Hold antibiotics until sampling
Anatomical considerations Thecal sac, pedicles, disc space Thecal sac, nerve root, intervertebral disc Pedicles, transverse processes, facets L5 nerve roots
Complications feared with approach chosen Wound issues Wound complication, progressive infection Reinfection, CSF leak Wound complication
Intraoperative
Anesthesia General General General General
Exposure L4-5 L5-sacrum L2-sacrum L4-S1
Levels decompressed L4-5 L5 None L4-S1
Levels fused L4-5 None L2-iliac L4-S1
Surgical narrative Position prone, place reference array on iliac crest, O-arm spin and navigation acquisition, bilateral paramedian incisions, place percutaneous MIS pedicle screws at L5-S1, dock MIS tubular retractor over L5-S1 facet joint for TLIF, facetectomy under microscope, TLIF and cage placement, swab disc space, irrigate with antibiotics, place vancomycin powder, place auto and allograft, place rods, standard closure Position prone, midline incision L5-sacrum, dissect in surgical layers until reaching space between L5 lamina and sacrum, cut yellow ligament, protect thecal sac and nerve roots, take cultures, biopsy disc space, wash with antiseptic solution, place Garacoll if available, layered closure Position prone, linear incision from L2-sacrum, dissection of paravertebral muscles, identify facets and transverse processes, locate pedicle insertion sites, placement of pedicle screws with fluoroscopic verification, verify pedicle integrity, insert screws from L2 to S1, locate iliac bone, wedge excision on iliac bone after dissection of iliac, iliac tunneling, iliac screw placement, layered closure with drain Position prone on Jackson table, localizing x-ray, midline incision, insert pedicle screws L4-S1 using navigation, L5-S1 laminectomy with discectomy, send samples from disc space, irrigate with 3 L of vancomycin and gentamycin, insert rods, perform fusion with allograft from L4 to S1, close with subfascial drain, PICC line for antibiotics
Complication avoidance MIS, percutaneous pedicle screws, indirect decompression of nerve roots Aim for disc space, protect neural structures when biopsy disc, place Garacoll if possible Anatomical placement of pedicle screws Hold antibiotics until samples obtained, surgical navigation
Postoperative
Admission Floor Floor ICU Floor
Postoperative complications feared Persistent infection Progress infection, neurological injury Reinfection, neurological injury, CSF leak Failure of fusion, wound breakdown
Anticipated length of stay 3–4 days 7 days 3 days 4–5 days
Follow-up testing

  • Infectious disease follow-up

  • L-spine x-ray 4 weeks after surgery

  • MRI L-spine 3 months after surgery

  • CT L-spine 3 months after surgery

CBC/ESR/CRP 48 hours after surgery

  • L-spine x-ray within 24 hours, and 1 month, 3 months, 6 months after surgery

  • Monthly CBC/ESR/CRP

  • MRI L-spine 6 weeks after surgery

  • Lumbar spine x-rays at 1 month, 3 months, 6 months, 12 months after surgery

Bracing None None None None
Follow-up visits 4 weeks, 3 months, 6 months after surgery 1 week after surgery 10 days, 1 month, 3 months, 6 months after surgery 2 weeks, 1 month, 3 months, 6 months, 1 year after surgery
BCG , Bacille Calmette–Guérin; CBC , complete blood count; CRP , C-reactive protein; CSF , cerebrospinal fluid; CT , computed tomography; ESR , erythrocyte sedimentation rate; IOM , intraoperative monitoring; MEP , motor evoked potential; MIS , minimally invasive surgery; MRI , magnetic resonance imaging; SSEP , somatosensory evoked potential; TLIF , transforaminal lumbar interbody fusion.

Differential diagnosis

  • ▪

    Vertebral osteomyelitis/discitis

  • ▪

    Malignancy

  • ▪

    Retroperitoneal infection

  • ▪

    Spondylosis

  • ▪

    Vertebral body and pars interarticularis fracture

You're Reading a Preview

Become a Clinical Tree membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here

Related Posts