Pulsed Radiofrequency Ablation and Steroid Injections for the Treatment of Meralgia Paresthetica

Ankara City Hospital Bilkent22 enrolled

Overview

Meralgia Paresthetica (MP) is a mononeuropathy of the lateral femoral cutaneous nerve (LFCN), characterized by pain, numbness, hyperesthesia, or hypoesthesia, especially in the anterolateral thigh where the nerve has a sensory distribution. TheLFCN passes between the psoas and quadratus lumborum muscles in the iliac fossa and enters the thigh under the inguinal ligament by passing through the anterior superior iliac spine over the iliacus muscle. It superficially spreads over the sartorius muscle and receives sensation in the anterolateral thigh. Ultrasonography (US) is frequently used by physiatrists in the diagnosis and interventional treatment of musculoskeletal diseases. MP is usually diagnosed with clinical symptoms such as burning, tingling, pain, and dysesthesia in the anterolateral thigh. Electromyography, US, and magnetic resonance imaging are helpful in diagnosis. US is an easy-to-apply, inexpensive method in daily practice, providing great comfort to clinicians in determining etiology and differential diagnosis. Treatment may include patient education, avoiding tight belts, losing weight, conservative treatment methods, use of non-steroidal anti-inflammatory drugs, local anesthetic and/or steroid injections, surgical neurectomy, neurolysis or transpositions. However, in recent years, there have been case series showing that radiofrequency ablation (RF) can also be applied. The aim of this study is to compare the effectiveness of RF ablation of the lateral femoral cutaneous nerve with steroid injection in patients with clinically diagnosed MP and confirmed by US.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Interventions

Pulsed Radiofrequency AblationPROCEDURE

The area where the lateral femoral cutaneous nerve is seen with US will be anesthetized with 1 ml of 1% lidocaine and a 22 Gauge, 10 cm-5 mm RF cannula will be inserted. Sensory fibers will be stimulated with 0.3-0.5 V. Then, motor fibers will be stimulated up to 1.5 V. If no motor contraction is seen, LFCN will be ablated at 42 degrees Celsius for 240 seconds. The procedure will be completed with the injection of 2 ml of 2% lidocaine and 2 ml (8 mg) dexamethasone through the RF cannula.

Steroid (dexamethasone) InjectionDRUG

Where the lateral femoral cutaneous nerve is visible with US, 2 ml of 2% lidocaine and 2 ml (8 mg) dexamethasone will be injected.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 90 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients with numbness, tingling and pain in the anterolateral thigh region * Patients with edematous LFCN observed on ultrasound and diagnosed with MP and with complaints resistant to conservative treatment * Being literate Exclusion Criteria: * History of lumbar discopathy or history of discopathy surgery * Cardiac pacemaker * History of bilateral hip, knee, foot and lumbar region fractures * History of previous hip and knee surgery * Fixed joint contracture in the lower extremity * History of malignancy and chemotherapy or radiotherapy * Presence of any neuromuscular disease * Progressive or non-progressive central and peripheral nervous system disease * Patients in pregnancy and lactation * Bleeding diathesis, INR\>1.2 * Uncontrolled diabetes or other serious comorbidities * Allergy to drugs or materials used * Local infections or sepsis

Outcomes

Primary Outcomes

Visual Analog Scale

The patients' pain levels were assessed using the Visual Analog Scale (VAS). The VAS pain score was scored as "no pain" (score=0) and "worst pain" (score=10).

Time frame: Baseline, 1st day, 2nd week, 3rd month, 6th month

Secondary Outcomes

The Leeds Assessment of Neuropathic Symptoms and Signs pain scale

The Leeds Assessment of Neuropathic Symptoms and Signs pain scale will be used to assess the presence of neuropathic pain. It consists of two subcategories: pain questionnaire and sensory assessment. The questionnaire consists of five questions about general pain symptoms of the patient, and two questions, that are answered after appropriate clinical examination following predetermined methodology, which includes the seek for allodynia and altered pinprick threshold Scoring varies between 0 and 24 points, with a total score \> 12 indicating pain predominantly of neuropathic etiology.