Posterior Leg Pain After InterStim Removal
For posterior leg pain occurring 1 week after InterStim removal, initiate multimodal pain management with gabapentinoids as first-line therapy (pregabalin 75-150 mg twice daily), combined with acetaminophen and NSAIDs if not contraindicated, while performing urgent neurological assessment to exclude nerve injury from the removal procedure. 1
Immediate Clinical Assessment
Rule out surgical complications first. Assess for new neurological deficits including motor weakness, sensory changes in a dermatomal pattern, and any signs suggesting nerve injury during the removal procedure 1. The posterior leg pain distribution may indicate S2-4 nerve root involvement, which is anatomically relevant given the sacral location of InterStim leads 2.
- Document the exact pain distribution: posterior thigh pain radiating to the popliteal fossa suggests S2-4 nerve territory involvement 2
- Perform motor examination testing knee strength/reflexes, foot dorsiflexion and plantarflexion strength, and ankle reflexes 1
- Map sensory distribution to identify specific dermatomal patterns versus non-dermatomal pain 3
- Check for associated numbness or tingling, which commonly accompanies nerve-related pain in this distribution 3, 2
Critical red flags requiring urgent imaging: Progressive motor weakness, saddle anesthesia, bowel/bladder dysfunction, or severe uncontrolled pain warrant immediate MRI to exclude epidural hematoma or abscess 1.
Multimodal Pain Management Protocol
Initiate gabapentinoids as first-line therapy. Pregabalin 75-150 mg twice daily has demonstrated efficacy for neuropathic leg pain and is FDA-approved for this indication 1, 4. This addresses the likely neuropathic component given the nerve proximity during lead removal.
Add non-opioid analgesics:
- Acetaminophen 1000 mg every 6 hours as a safer baseline analgesic 1, 4
- NSAIDs or COX-2 selective inhibitors (such as celecoxib) unless contraindicated by bleeding risk or anticoagulation 4, 1
- Avoid combining NSAIDs with therapeutic anticoagulation, which increases bleeding risk 2.5-fold 4
Minimize opioid use. If pain remains severe despite the above measures, prescribe the lowest effective opioid dose for no more than 7 days 1. Patients not experiencing meaningful relief within 1 month are unlikely to benefit from continued opioid therapy and should not have opioids continued 1.
Specific Considerations for Post-InterStim Removal
This pain pattern mirrors sacral nerve injury. Case series of uterosacral ligament suspension (which also involves S2-4 nerve territory) describe identical presentations: sharp buttock pain with numbness radiating down the posterior thigh to the popliteal fossa within 24 hours of surgery 2. In those cases, symptoms resolved either with suture removal (within 2 days) or with gabapentin and narcotics over 12-14 weeks 2.
Expected timeline for resolution: Based on similar sacral nerve injuries, expect gradual improvement over 6-12 weeks with conservative management 2. Complete resolution may take up to 6 months in some cases 2.
Rehabilitation and Functional Recovery
Implement early mobilization. Avoid prolonged immobilization which leads to deconditioning 1. Encourage optimal spinal alignment and postural modifications 1.
Consider physical therapy if symptoms persist beyond 6-8 weeks, incorporating multidisciplinary rehabilitation combining physical, vocational, and behavioral components 1.
Critical Pitfalls to Avoid
Don't overlook alternative diagnoses. While nerve injury from lead removal is most likely, consider:
- Deep posterior compartment syndrome if pain is exercise-induced with tightness and cramps 5
- Sacroiliac joint dysfunction if pain centers around the PSIS with non-dermatomal leg symptoms 3
- Vascular causes are unlikely but obtain ankle-brachial index if pain occurs predictably with walking 1, 4
Don't ignore psychosocial factors. Depression, catastrophizing, and passive coping predict worse outcomes and should be addressed if symptoms persist 1.
Don't continue ineffective treatments. Reassess the pain management strategy at 1 month; if no meaningful improvement occurs, escalate to pain management specialist referral rather than continuing the same regimen 1, 4.