Page 118 - Journal of Special Operations Medicine - Spring 2017

An Ongoing Series

Load Carriage–Related Paresthesias (Part 2)

Meralgia Paresthetica

Joseph J. Knapik, ScD; Katy Reynolds, MD;
Robin Orr, PhD; Rodney Pope, PhD

ABSTRACT

This is the second of a two-part series addressing Keywords: paresthesias, load carriage–related; meralgia
symptoms, evaluation, and treatment of load carriage– paresthetica; mononeuropathy; nerve, lateral femoral cuta-
related paresthesias. Part 1 addressed rucksack palsy neous; Bernhardt–Roth syndrome
and digitalgia paresthetica; here, meralgia paresthetica
(MP) is discussed. MP is a mononeuropathy involv-
ing the lateral femoral cutaneous nerve (LFCN). MP Introduction
has been reported in load carriage situations where
the LFCN was compressed by rucksack hipbelts, pis- Paresthesias are sensations of numbness, burning, and/
tol belts, parachute harnesses, and body armor. In the or tingling, usually experienced as a result of nerve in-
US military, the rate of MP is 6.2 cases/10,000 person- jury or irritation. Several types of compression-related
1
years. Military Servicewomen have higher rates than paresthesias have been described in association with
Servicemen, and rates increase with age, longer load- load carriage, including brachial plexus palsy, digital-
carriage distance or duration, and higher body mass gia paresthetica, and meralgia paresthetica (MP). These
index. Patients typically present with pain, itching, and are important to understand in the military context be-
paresthesia on the anterolateral aspect of the thigh. cause Soldiers who carry heavy loads and wear body
There are no motor impairments or muscle weakness, armor may present with symptoms indicative of these
because the LFCN is entirely sensory. Symptoms may types of injuries. This is the second of a two-part series
be present on standing and/or walking, and may be addressing symptoms, diagnosis, treatment, and preven-
relieved by adopting other postures. Clinical tests to tion of load carriage–related paresthesias. In Part 1, we
evaluate MP include the pelvic compression test, the addressed rucksack palsy and digitalgia paresthetica; in
femoral nerve neurodynamic test, and nerve blocks us- Part 2, we examine MP in detail.
ing lidocaine or procaine. In cases where these clini-
cal tests do not confirm the diagnosis, specialized tests MP is a neurological disorder involving the lateral fem-
might be considered, including somatosensory evoked oral cutaneous nerve (LFCN) and is characterized by
potentials, sensory nerve conduction studies, high-res- pain, itching, and paresthesia on the anterolateral as-
olution ultrasound, and magnetic resonance imaging. pect of the thigh (Figure 1). The disorder has also been
Treatment should initially be conservative. Options termed Bernhardt–Roth syndrome and lateral femoral
2,3
include identifying and removing the compression if cutaneous neuralgia. Bernhardt–Roth syndrome was
2–4
it is external, nonsteroidal inflammatory medication, named after Martin Bernhardt, who first described the
manual therapy, and/or topical treatment with capsa- condition, and Vladimir Roth, who later identified the
icin cream. Treatments for intractable cases include in- condition in an Army officer wearing a tight belt. 2,3
jection of corticosteroids or local anesthetics, pulsed
radiofrequency, electroacupuncture, and surgery. Mili- Epidemiology
tary medical care providers may see cases of MP, es-
pecially if they are involved with units that perform Table 1 lists the prevalence or rates of MP that have been
regular operations involving load carriage. reported in various investigations. The prevalence among

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