Meralgia Paresthetica
- Picture shows affected area in this condition - burning pain and paresthesia
- Pts complain of "feels like someone is placing a tennis racquet on my leg"
- Lateral femoral cutaneous (L2 & L3) nerve affected (entrapment beneath inguinal ligament or sartorius/TFL)
Demographics/Risk factors
- Occurs at any age - most often affects middle aged adults |
- Diabetics |
- Can be bilateral |
- Can be either side if unilateral |
- Men more than women (work - carpentry tool belts, police duty belts, soldier body armour) |
- Excessive compression/ischemic stretch |
- Tight clothing |
- Pregnancy |
- Obesity (>30 BMI) |
- Seatbelt compression |
- Excessive prone lying on hard surface |
- Athletes (gymnastics, baseball, soccer, bodybuilding, strenuous exercise) |
- Excessive anterior pelvic tilt , Leg length inequality |
Presentation
- Middle aged patient with >1 of risk factors |
- Isolated pain/paraesthesia/hypersensitivity on outside of thigh |
- Dull, aching, itching, buzzing, burning |
- Can impair sleep + ADLs |
- Aggravated by walking , hip/lx ext |
- Relieved by sitting (decreases tension on inguinal ligament) |
- Screen for diabetes (family hx, hypertension, age, gender, ethnicity, physical activity level, SOB, BMI frequent thirst, pulses, vibration sensation |
- TTP over lateral inguinal ligament (1 - 2 finger widths inferior and medial to ASIS) |
- +ve Yeomans, +ve Tinels , +ve NTT of LFCN |
- Assess for hypertonic iliopsoas, TFL, Sartorius |
- Assess for joint dysfunction of Lx, SI, hip |
- Assess for lower crossed, leg length inequality, paradoxical breathing |
- Neurological exam - numbness/hyperesthesia over distribution of LCFN (above picture) |
- If motor/reflex signs present, consider other diagnosis - disc/radiculopathy - LFCN is a purely sensory nerve |
Imaging
- Not usually required (well defined) |
-Nerve conduction study gold standard |
- MRI if mass/lesion in retroperitoneal space/lx radiculopathy |
DDx
- Lx radiculopathy |
- Trigger point referral (glut medius/TFL |
- Retroperitoneal, abdominal, pelvic pathology |
- Lx disc lesion |
- Diabetes |
Management
- Highly successful (>90%) |
- Advise patient to wear looser clothing |
- Rest from aggravating activity (repetitive hip flexion |
- Loosing weight |
- Carrying a toolbox instead of a belt |
- Not wearing high heels (causes excessive anterior pelvic tilt) |
- Myofascial release/stretching of hip flexors, sartorius, TFL, Quads, thigh adductors |
- Nerve mobilisation |
- Stabilisation of core and pelvis |
- Ice and NSAIDs |
- Severe cases - anesthetic block/steroid injection |
- If not better, surgical decompression is indicated |
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