What are the symptoms and treatment options for Meralgia Paresthetica?

Meralgia Paresthetica: Symptoms and Treatment

Meralgia paresthetica is characterized by tingling, numbness, burning pain, and sensory alterations in the anterolateral thigh due to compression or entrapment of the lateral femoral cutaneous nerve (LFCN). 1, 2

Clinical Presentation

• Paresthesias (tingling, numbness) in the anterolateral thigh region 1, 2
• Burning or lancinating neuropathic pain in the distribution of the lateral femoral cutaneous nerve 2, 3
• Sensory disturbances including allodynia (pain from normally non-painful stimuli) and hyperalgesia (increased sensitivity to pain) 4
• Symptoms typically unilateral but can be bilateral in some cases 3
• Pain may worsen with prolonged standing, walking, or hip extension 3, 5
• Symptoms often exacerbated by tight clothing around the waist 3, 5

Risk Factors

• Obesity (increased pressure on the inguinal region) 2, 5
• Pregnancy (especially in later trimesters) 5
• Diabetes mellitus 2
• Tight clothing or belts 3, 5
• Recent weight gain 2
• Previous pelvic or hip surgery 3
• Prone positioning during spine surgery 3

Diagnostic Approach

• Clinical diagnosis based on characteristic symptoms and distribution 1, 3
• Diagnostic nerve block with local anesthetic can confirm diagnosis (relief of symptoms indicates correct diagnosis) 3, 6
• Electromyography and nerve conduction studies may help rule out other conditions 1, 2
• MRI or ultrasound may be used to identify nerve compression or rule out other pathologies 1

Treatment Algorithm

First-Line Management (0-4 weeks)

• Conservative measures:

  • Weight loss for obese patients 5
  • Avoidance of tight clothing around the waist 3, 5
  • Activity modification to reduce pressure on the nerve 3
  • NSAIDs for pain relief 5, 6

• First-line medications for neuropathic pain:

  • Gabapentin (starting at 300 mg at bedtime, up to 2400 mg daily divided into 3 doses) 4
  • Pregabalin (75-300 mg every 12 hours) 4

Second-Line Management (4-12 weeks)

• Tricyclic antidepressants such as amitriptyline for persistent neuropathic pain 4
• Serotonin-norepinephrine reuptake inhibitors like venlafaxine (up to 75 mg daily) 4
• Local anesthetic and corticosteroid injections around the LFCN at the anterior superior iliac spine 3, 5, 6

Third-Line Management (>12 weeks)

• Surgical intervention if conservative measures fail after 3-4 months:
  • Neurolysis (nerve decompression) 3, 6
  • Neurectomy (transection of the nerve) - controversial but may be considered for intractable pain 3, 6
• Pulsed radiofrequency neuromodulation for refractory cases 2

Treatment Considerations

• Most cases (especially idiopathic) improve with conservative management 3
• Surgical options should only be considered after failure of conservative measures 4, 6
• Medication side effects to monitor:
  • Somnolence with gabapentin/pregabalin 4
  • Anticholinergic effects with tricyclic antidepressants 4
  • Edema of lower limbs with gabapentin 4

Prognosis

• Generally excellent with appropriate treatment 2
• Many cases are self-limiting but may cause significant discomfort during the active phase 5
• Surgical outcomes are typically good when conservative management fails 6