Research Methodology

Inclusion/exclusion criteria

• Includes all elective spine procedures
• Excludes emergency cases, hospital/trauma consults, peripheral nerve, cranial, and spinal cord stimulator cases
• Validated through insurance billing records to ensure all eligible patients are included

Patient profile

• Demographics, conservative treatments, co-morbidities (other medical conditions), previous spine surgeries
• Self-reported by patient, previous PCP/provider notes
• Data collected through individual chart review

Primary diagnosis

• Defined as the primary indication or reason for surgery
• Documented by surgeon, imaging studies
• Data collected through individual chart review

Surgical summary

• Date, length of stay, OR time, levels treated, procedure, instrumentation
• Documented by surgeon, anesthesiologist, and nurses in hospital anesthesiology reports, operative notes, discharge summaries, and intra-operative data collection forms

Complications: intraoperative

• Documented by surgeon in operative notes
• Examples:
  • Incidental durotomy (hole in dura)
  • Cardiopulmonary
  • Excessive blood loss/vascular injury
  • Injury to bowel, bladder, or spinal cord
  • Tension pneumothorax (air) or hemothorax (blood) in chest cavity causing problems breathing

Complications: medical

• Any medical complication within 30 days of surgery
• Examples:
  • Death
  • Urinary tract infection (UTI)
  • Urinary retention
  • DVT (clot in leg)
  • Pulmonary embolus (PE)
  • Anemia requiring transfusion
  • Prolonged hospital stay
  • Pneumonia
  • Myocardial infarction (MI)/heart attack
  • Stroke
  • Exacerbation of underlying medical conditions (worsening COPD)
  • Serious reactions to medications
  • Excludes:
    • Visit to ER without hospital admission
    • Constipation
    • Nausea
    • Small bump under incision without hematoma
    • Minor medication allergies

Complications: procedure related (no 30 day time limit)

• Examples:
  • Subsidence or loss of correction requiring revision
  • Hardware failure
  • Pseudoarthroses (failure to fuse)
  • Discitis (disc space infection)
  • Retrograde ejaculation
  • Vascular injury
  • Superficial wound dehiscence (breakdown, without infection)
  • Wound infection (superficial or deep)
  • New motor weakness 1 grade or more (1/2 – 1 grade = minor, > 1 grade major)
  • Hematoma requiring intervention (superficial, asymptomatic excluded)
  • Loss of alignment or stability requiring surgery
  • Any unplanned return to OR (excluding exploratory with negative findings)
  • Excludes:
    • Subsidence without failed fusion
    • “Side effects” lasting less than 3 months
    • New numbness or tingling without weakness
    • Recurrent disc herniation

Complications specific to cervical procedures:

• Examples

1. Same as those listed above
2. Prolonged dysphagia: unresolved after 3 months (< 3 months not considered a complication, it’s a common side effect)
3. Excessive pre-vertebral swelling in early post-op period requiring readmit (if already discharged), steroids, observation, or NG/PEG tube for dysphagia, respiratory difficulties, or both
4. Hoarseness
5. New weakness

• Excluded:  As above

Follow-up rates

• In real world without financial incentives associated with studies at academic institutions, it’s often difficult to get patients to follow-up. Issues such as changes in insurance plans/coverage,  relocation, loss of insurance, or unpaid balance often hinder proper follow-up
• Complications may not be the most complete if not reported by patient or other providers, affected by those lost to follow-up