April 11, 2024

Failed back surgery syndrome is a misnomer as it is actually a syndrome complex where the patient presents with persistent or new-onset back or leg pain followed by back surgery. Causes are

  • Organic
  • Psychological
Failed back surgery syndrome
Back Pain

Etiology of Failed back surgery syndrome

Inadequate Primary surgery

The wrong level of surgery

Inadequate or inappropriate surgery

Iatrogenic instability

Arachnoiditis, epidural fibrosis, infection, implant failure, etc

Unrelated to Primary Surgery

Recurrence of disc prolapsed

Adjacent level pathology (Spondylosis, Spondylolisthesis, Disc degeneration, Proximal junctional problems)

Epidural fibrosis

Ongoing degenerative pathology

Psychological

Depression

Chronic pain syndrome

Fibromyalgia

Classifications

  1. Post-operative (0-2 days to 6 weeks)
  2. Intermediate (6 weeks to 6 months)
  3. Late-onset ( > 6 months )

Physical tests

  • Tenderness tests: Superficial and diffused tenderness
  • Simulation test: Pain on axial loading and on simulated rotations
  • Distraction test: Positive tests are rechecked when the patient’s attention is distracted. eg. SLR
  • Regional disturbances: motor/sensory weakness
  • Overreactions

Investigations

Diagnostic Blocks:

Selective nerve root blocks are helpful to confirm the exact locations of abnormalities and anesthetic responses.

Treatment options

Non-Operative treatment

  • Physical therapy / Behavioral therapy
  • Anticonvulsant: Neuropathic pain
  • Antibiotics
  • Selective nerve root blocks
  • Spinal cord stimulations
  • Epidural/Intrathecal analgesics

Operative

Revision fusion is challenging as it leaves scar and fibrosis from previous surgery and makes it difficult to identify anatomical landmarks.

Principle of Revision Spine Surgery

  • Most of the cases can be approached from the back/ posterior approach entered by a midline approach/ Witse approach
  • Wide exposure through unoperated normal anatomy
  • Careful exposure of facet joint and lateral border of pars and approaching midline from lateral to medial
  • Curette, small size Kerrison rongeur or Penfield dural retractoràused to identify the edge of laminectomy defects
  • Good localization of the Dural sleeve should be done before mobilization of nerve roots
  • Lumbar fusion surgery has been used as a salvage surgery in patients who had already done lumbar decompression procedures.

See also: Approaches of Spine