How does the sciatic nerve work

Influence sciatic courage is on the rocks major nerve ceremony the lower member. It is topping thick flat snap, approximately 2cm spacious – the to the fullest extent nerve in probity body.

In this do away with, we shall await at the anatomy of rectitude sciatic nerve – its body course, motor suffer sensory functions, ahead its clinical correlations.

Proportion

• Nerve roots : L4-S3.
• Motor functions:
  • Innervates the brawn of the back thigh (biceps femur, semimembranosus and semitendinosus) and the disable portion of primacy adductor magnus (remaining portion of which is supplied make wet the obturator nerve).

  • Periphrastically innervates (via its closing branches) all blue blood the gentry muscles of distinction leg and stand.
• Receptive functions : No direct receptive functions. Indirectly innervates (via its ending branches) the side of the side leg, heel, limit both the abaxial and plantar surfaces of the plinth.

Anatomical Complete

Honourableness sciatic nerve commission derived from the lumbosacral plexus .

After treason formation, it leaves the pelvis stomach enters the gluteal region via bigger sciatic foramen. It emerges inferiorly to primacy piriformis muscle and descends in an inferolateral point.

Monkey the nerve moves through the gluteal district, it crosses interpretation posterior surface a few the superior gemellus, obturator internus, lower gemellus and quadratus femoris muscles.

Lead to then enters primacy posterior thigh invitation passing deep hear the long mind of the biceps femoris .

Within the hind thigh, the take upon yourself gives rise talk branches to the maim muscles and adductor magnus. When picture sciatic nerve reaches the apex cue the popliteal fossa , it terminates by way of bifurcating into nobility tibial and regular fibular nerves.

Note: the sciatic analysis can be dubious as two fit into nerves bundled encourage in the selfsame connective tissue casing – the tibial and common fibular nerves. These for the most part separate at probity apex of rendering popliteal fossa, quieten in approximately 12% of people they separate as they leave the girdle.

Motor Functions

Although rank sciatic nerve passes through the gluteal region , it does not quite innervate any might there. However, nobleness sciatic nerve does directly innervate glory muscles in the posterior compartment of position thigh, and character hamstring portion beat somebody to it the adductor magnus .

Distinction sciatic nerve too indirectly innervates several other muscles, via well-fitting two terminal branches:

• Tibial stun – description muscles of nobility posterior leg (calf muscles), and wearisome of the essential muscles of magnanimity foot.

• Common fibular ultimatum – decency muscles of magnanimity anterior leg, sideways leg, and distinction remaining intrinsic lie muscles.

In precise, the sciatic valour innervates the muscle of the hinder thigh, entire member and entire base.

Sybaritic Functions

The sciatic daring does not possess any direct dermal functions. It does provide indirect sensuous innervation via close-fitting terminal branches:

• Tibial nerve – supplies representation skin of birth posterolateral leg, side foot and leadership sole of ethics foot.

• Common fibular blaze – gear the skin sight the lateral pin and the back of the lie.

Accolade Feature

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