Unilateral Lower Extremity Swelling After Laminectomy
Unilateral leg swelling after lumbar laminectomy is NOT a normal postoperative finding and requires immediate evaluation to rule out deep vein thrombosis (DVT), infection, or other serious complications.
Why This Is Concerning
Unilateral leg swelling is distinctly different from the expected postoperative course after laminectomy and should trigger urgent diagnostic workup:
Expected vs. Abnormal Postoperative Findings
Normal postoperative findings include:
- Bilateral mild lower extremity edema from positioning and fluid shifts 1
- Wound drainage requiring monitoring every 4 hours 1
- Temporary numbness or nerve root symptoms that are typically bilateral or radicular in distribution 2
Abnormal findings requiring investigation:
- Unilateral leg swelling suggests venous thrombosis, compartment syndrome, or asymmetric nerve injury 1
- Wound complications occur in up to 9-12% of cases and can present with localized swelling 1, 3
- Nerve root palsy (C-5 palsy in cervical cases occurs in 2-6% within 24-48 hours) can cause unilateral symptoms but typically presents as weakness rather than isolated swelling 1
Differential Diagnosis to Rule Out
Life-Threatening Complications
- Deep vein thrombosis (DVT): Most critical diagnosis to exclude, as untreated DVT can lead to pulmonary embolism with significant mortality risk 1
- Compartment syndrome: Rare but devastating if missed, requires emergent fasciotomy 1
Serious but Non-Life-Threatening Complications
- Deep wound infection or abscess: Can occur in up to 9-12% of multilevel cases and may present with unilateral swelling if tracking along tissue planes 1, 4
- Cerebrospinal fluid collection (liquorcele): A rare complication that can present as postoperative swelling, though typically presents as lumbar/back swelling rather than leg swelling 5
- Hematoma: Can cause mass effect and unilateral symptoms if compressing nerve roots 1
Less Urgent Causes
- Asymmetric positioning injury: Prolonged surgical positioning can cause unilateral edema, though this should resolve rapidly 1
- Unilateral nerve root injury: May cause localized swelling from denervation changes 2, 3
Immediate Workup Required
Do not adopt a "wait and see" approach with unilateral leg swelling:
- Doppler ultrasound of the affected extremity to rule out DVT (highest priority) 1
- Clinical examination for signs of infection: fever, wound erythema, drainage, warmth 1, 4
- Neurological examination to assess for new motor or sensory deficits suggesting nerve root compression from hematoma or abscess 1, 3
- Compartment pressure measurement if clinical suspicion exists (pain out of proportion, tense compartments) 1
- MRI of the surgical site if infection, hematoma, or CSF collection suspected based on clinical findings 5
Common Pitfalls to Avoid
- Assuming all postoperative swelling is "normal": Bilateral mild edema may be expected, but unilateral swelling is a red flag 1
- Delaying DVT workup: The mortality rate for untreated complications like pulmonary embolism is significant; early detection is critical 6
- Missing early infection: Wound infections can progress rapidly to osteomyelitis if not identified early, with devastating long-term consequences 4
- Attributing symptoms to "surgical trauma" without objective evaluation: This delays diagnosis of treatable complications 7