What are the treatment options for neuropathy after reverse total shoulder replacement surgery?

Treatment Options for Neuropathy After Reverse Total Shoulder Arthroplasty

The first-line treatment for neuropathy after reverse total shoulder arthroplasty should include gabapentin or pregabalin, which are effective for managing neuropathic pain with good evidence for efficacy and tolerability. 1

Medication Options

First-Line Treatments

• Gabapentin and pregabalin are recommended as first-line treatments for neuropathic pain, acting by binding to the α-2-δ subunit of voltage-gated calcium channels 1
• Start with low doses and titrate gradually: gabapentin typically titrated to 2400 mg per day in divided doses 1
• Pregabalin can be started at 75 mg twice daily and titrated as needed up to 300-600 mg/day 1
• Dose adjustments are necessary in patients with renal impairment 1

Alternative First-Line Options

• Tricyclic antidepressants (TCAs) like nortriptyline and desipramine are effective first-line alternatives 1
• Start TCAs at low doses (10 mg/day) and titrate slowly to a maximum of 75 mg/day, especially in older adults 1
• Obtain a screening ECG for patients over 40 years before starting TCAs due to potential cardiac risks 1
• Selective serotonin-norepinephrine reuptake inhibitors (SNRIs) like duloxetine (60-120 mg/day) and venlafaxine (150-225 mg/day) have fewer anticholinergic effects than TCAs 1

Topical Treatments

• Consider 5% lidocaine patches for localized peripheral neuropathic pain, particularly with allodynia 1
• High-concentration capsaicin patches may be beneficial for localized neuropathic pain 1

Treatment Algorithm

1. Assess the type and location of neuropathy:

   • Determine which nerve is affected - axillary nerve (41.2%) and radial nerve (15%) are most commonly involved after RTSA 2
   • Evaluate for symptoms such as numbness, tingling, hyperalgesia, and/or allodynia in the distribution of the affected nerve 3

2. First-line treatment:

   • For diffuse neuropathic pain: Start with gabapentin or pregabalin 1
   • For localized peripheral neuropathic pain: Consider topical lidocaine or capsaicin 1

3. If partial response after adequate trial:

   • Add another first-line agent from a different class (e.g., add duloxetine to gabapentin) 1

4. If inadequate response to first-line agents:

   • Consider second-line treatments such as tramadol (starting at 50 mg once or twice daily, maximum 400 mg/day) 1
   • Use lower doses in older adults and those with renal/hepatic dysfunction 1

5. For refractory cases:

   • Consider referral to pain specialist or multidisciplinary pain center 1
   • Peripheral nerve stimulation may be an option for persistent pain - a case report showed improvement in shoulder function and pain reduction with axillary nerve stimulation 4

Special Considerations

• Most neurologic deficits after RTSA are temporary and resolve with conservative management - studies show complete recovery in most patients within an average of 7.4 months 2
• Neurologic deficit after RTSA occurs in approximately 19% of patients and is significantly correlated with humeral distalization after surgery 2
• Distal peripheral neuropathy (DPN) is an under-reported complication after shoulder surgery, with 12.3% of reverse shoulder arthroplasty patients developing DPN 5
• The most common form of DPN after RTSA is cubital tunnel syndrome 5
• Conservative treatment resolves symptoms in approximately 42.86% of RTSA patients with DPN, but 14.3% may require surgical decompression 5
• Surgical decompression is highly effective for refractory cases, with 100% of patients achieving complete resolution of symptoms after decompression 5

Monitoring and Follow-up

• Regular assessment of pain intensity, functional improvement, and adverse effects 1
• If substantial pain relief (≥50% reduction) is achieved with tolerable side effects, continue treatment 1
• For patients with ulnar nerve neuropathy after RTSA, electrodiagnostic and ultrasound studies should be performed to confirm and assess the site and severity of the injury 3
• Be aware that surgical intervention for ulnar nerve neuropathy following RTSA may have limited success, with complete symptom resolution in only a minority of patients 3