The lateral cutaneous nerve of the thigh (also called the lateral femoral cutaneous nerve) is a

cutaneous nerve A cutaneous nerve is a nerve that provides nerve supply to the skin. Human anatomy In human anatomy, cutaneous nerves are primarily responsible for providing sensory innervation to the skin. In addition to sympathetic and autonomic afferent (sens ...

of the

thigh In human anatomy, the thigh is the area between the hip (pelvis) and the knee. Anatomically, it is part of the lower limb. The single bone in the thigh is called the femur. This bone is very thick and strong (due to the high proportion of bone ...

. It originates from the dorsal divisions of the second and third

lumbar nerves The lumbar nerves are the five pairs of spinal nerves emerging from the lumbar vertebrae. They are divided into posterior and anterior divisions. Structure The lumbar nerves are five spinal nerves which arise from either side of the spinal cord b ...

from the

lumbar plexus The lumbar plexus is a web of nerves (a nervous plexus) in the lumbar region of the body which forms part of the larger lumbosacral plexus. It is formed by the Ventral ramus of spinal nerve, divisions of the first four lumbar nerves (L1-L4) and ...

. It passes under the

inguinal ligament The inguinal ligament (), also known as Poupart's ligament or groin ligament, is a band running from the pubic tubercle to the anterior superior iliac spine. It forms the base of the inguinal canal through which an indirect inguinal hernia may dev ...

to reach the thigh. It supplies sensation to the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...

on the lateral part of the

by an anterior branch and a posterior branch. The lateral cutaneous nerve of the thigh can be investigated using

ultrasound Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hea ...

Local anaesthetic A local anesthetic (LA) is a medication that causes absence of pain sensation. In the context of surgery, a local anesthetic creates an absence of pain in a specific location of the body without a loss of consciousness, as opposed to a general ...

can be injected around the nerve for

skin grafts Skin grafting, a type of graft surgery, involves the transplantation of skin. The transplanted tissue is called a skin graft. Surgeons may use skin grafting to treat: * extensive wounding or trauma * burns * areas of extensive skin loss du ...

and

surgery Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pat ...

around the outer thigh. Nerve compression (usually around the

) can cause

meralgia paraesthetica Meralgia paresthetica or meralgia paraesthetica is numbness or pain in the outer thigh not caused by injury to the thigh, but by injury to a nerve that extends from the spinal column to the thigh. This chronic neurological disorder involve ...

Structure

The lateral cutaneous nerve of the thigh is a nerve of the

. It arises from the dorsal divisions of the second and third

(L2-L3). It passes through

psoas major muscle The psoas major ( or ; from grc, ψόᾱ, psóā, muscles of the loins) is a long fusiform muscle located in the lateral lumbar region between the vertebral column and the brim of the lesser pelvis. It joins the iliacus muscle to form the il ...

, and emerges from its lateral border. It crosses the

iliacus muscle The iliacus is a flat, triangular muscle which fills the iliac fossa. It forms the lateral portion of iliopsoas, providing flexion of the thigh and lower limb at the acetabulofemoral joint. Structure The iliacus arises from the iliac fossa on t ...

obliquely, toward the

anterior superior iliac spine The anterior superior iliac spine (abbreviated: ASIS) is a bony projection of the iliac bone, and an important landmark of surface anatomy. It refers to the anterior extremity of the iliac crest of the pelvis. It provides attachment for the ingui ...

(ASIS). It is crossed by the

deep circumflex iliac artery The deep circumflex iliac artery (or deep iliac circumflex artery) is an artery in the pelvis that travels along the iliac crest of the pelvic bone. Course The deep circumflex iliac artery arises from the lateral aspect of the external iliac arte ...

and the

deep circumflex iliac vein The deep circumflex iliac vein is formed by the union of the venae comitantes of the deep iliac circumflex artery, and joins the external iliac vein about 2 cm. above the inguinal ligament The inguinal ligament (), also known as Poupart's l ...

. It then passes under the

. It passes through the

muscular lacuna The muscular lacuna (Latin: ''lacuna musculorum'') is the lateral compartment of the thigh inferior to the inguinal ligament, for the passage of the iliopsoas muscle, the femoral nerve and the lateral cutaneous nerve of the thigh; it is separate ...

. It then passes over the

sartorius muscle The sartorius muscle () is the longest muscle in the human body. It is a long, thin, superficial muscle that runs down the length of the thigh in the Anterior compartment of thigh, anterior compartment. Structure The sartorius muscle originates f ...

into the thigh, travelling from medial to lateral. It is usually between 1 and 2 mm thick.

Branches

The lateral cutaneous nerve of the thigh usually divides into an anterior (or anterolateral) branch and a posterior branch.

Anterior branch

The anterior branch becomes superficial about 10 cm below the inguinal ligament. It divides into branches which are distributed to the skin of the anterior and lateral parts of the thigh, as far down as the knee. The terminal filaments of this nerve frequently communicate with the anterior cutaneous branches of the

femoral nerve The femoral nerve is a nerve in the thigh that supplies skin on the upper thigh and inner leg, and the muscles that extend the knee. Structure The femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest ...

, and with the infrapatellar branch of the

saphenous nerve The saphenous nerve (long or internal saphenous nerve) is the largest cutaneous branch Cutaneous innervation refers to the area of the skin which is supplied by a specific cutaneous nerve. Dermatome (Anatomy), Dermatomes are similar; however, a ...

, forming with them the peripatellar plexus.

Posterior branch

The posterior branch pierces the

fascia lata The fascia lata is the deep fascia of the thigh. It encloses the thigh muscles and forms the outer limit of the fascial compartments of thigh, which are internally separated by the medial intermuscular septum and the lateral intermuscular septu ...

. It subdivides into filaments, which pass backward across the lateral and posterior surfaces of the thigh. It supplies the skin around the

greater trochanter The greater trochanter of the femur is a large, irregular, quadrilateral eminence and a part of the skeletal system. It is directed lateral and medially and slightly posterior. In the adult it is about 2–4 cm lower than the femoral head.Stan ...

Variation

The lateral cutaneous nerve of the thigh may have multiple branches. Its position with relation to the ASIS can be very variable. It may partially pass through

rather than over its surface. It may be absent, and the sensory supply replaced by branches of the

and the

ilioinguinal nerve The ilioinguinal nerve is a branch of the first lumbar nerve (L1). It separates from the first lumbar nerve along with the larger iliohypogastric nerve. It emerges from the lateral border of the psoas major just inferior to the iliohypogastric, an ...

Function

The lateral cutaneous nerve of the thigh is a

sensory nerve A sensory nerve, or afferent nerve, is a general anatomic term for a nerve which contains predominantly somatic afferent nerve fibers. Afferent nerve fibers in a sensory nerve carry sensory information toward the central nervous system (CNS) fr ...

. It supplies the

on the lateral (outer) part of the

Clinical significance

Ultrasound

The lateral cutaneous nerve of the thigh can be studied using ultrasound. A patient lies on a bed facing upwards (supine). The ultrasound probe is moved along the length of the nerve, often starting from near the ASIS. The nerve is easier to see over the

than in other subcutaneous tissue, as there is greater contrast. It can sometimes be difficult to see due to surrounding soft tissue.

Nerve block

The lateral cutaneous nerve of the thigh can be blocked with

local anaesthetic A local anesthetic (LA) is a medication that causes absence of pain sensation. In the context of surgery, a local anesthetic creates an absence of pain in a specific location of the body without a loss of consciousness, as opposed to a general ...

. Ultrasound is used to guide needle insertion. This is used for procedures in the supplied area of skin, such as surgical incisions over the outer thigh, and

Meralgia paraesthetica

Entrapment of the lateral cutaneous nerve of the thigh is caused by compression of the nerve near the

and the

. This causes

(

Bernhardt Bernhardt is both a given name and a surname, deriving from multiple languages, such as German. Notable people with the name include: Given name: *Bernhardt Esau (born 1957), Namibian politician and Deputy Ministry of Trade and Industry *Bernhardt ...

Roth Roth may refer to: Places Germany * Roth (district), in Bavaria, Germany ** Roth, Bavaria, capital of that district ** Roth (electoral district), a federal electoral district * Rhineland-Palatinate, Germany: ** Roth an der Our, in the district B ...

syndrome). This may be diagnosed with ultrasound, which changes the morphology of the nerve. Changes can include general enlargement, and a hypoechoic appearance. In patients who only have meralgia paraesthetica on one side, ultrasound scans are performed on both thighs to compare the appearance of the nerve.

History

The lateral cutaneous nerve of the thigh may also be known as the lateral femoral cutaneous nerve.

Additional images

File:Gray546-LFC.png, Lateral cutaneous nerve of thigh and other structures passing behind the inguinal ligament File:Gray580.png, The great saphenous vein and its tributaries at the fossa ovalis. File:Gray823.png, The lumbar plexus and its branches. File:Gray824.png, Deep and superficial dissection of the lumbar plexus. File:Gray826-LFC.png, Diagram of segmental distribution of the lateral cutaneous nerve (shaded) and other nerves of the right leg. Front view. File:Gray826and831.svg, Cutaneous nerves of the right lower extremity. Front and posterior views.

References

External links

* * - "Posterior Abdominal Wall: Nerves of the Lumbar Plexus" * () {{Authority control Nerves of the lower limb and lower torso

Structure

Branches

Anterior branch

Posterior branch

Variation

Function

Clinical significance

Ultrasound

Nerve block

Meralgia paraesthetica

History

Additional images

See also

References

External links