S1 NERVE

 

ORIGIN: Spinal cord segment S1.

COURSE/DISTRIBUTION: This nerve takes origin from spinal cord segment S1 and leaves the vertebral canal by passing through the dorsal sacral intervertebral foramen between S1 and S2 vertebrae. It immediately divides into two rami- dorsal and ventral rami.

Dorsal ramus:

It immediately turns backwards, under the cover of the multifidus and divided into medial and lateral branches.

bulletThe medial branch immediately passes to the multifidus where it ends.
bulletThe lateral branch runs laterally and join others to form loops on the posterior aspect of the sacrum. From these loops, cutaneous nerves emerge which pierce the gluteus maximus and supply the skin over the gluteal area. 

Ventral ramus:

The ventral ramus of S1 takes part in the formation of the sacral plexus. It divides into two branches. The upper branch enters the common peroneal part of sciatic nerve, while the lower enters the tibial part of the same nerve. A minor branch helps to form the posterior cutaneous nerve of thigh. 

BRANCHES.

bulletBranch 1 to form common peroneal part of sciatic nerve
bulletBranch 2 to form tibial part of sciatic nerve
bulletBranch 3 to form posterior cutaneous nerve of thigh.

ROOT VALUE: S1.

 

There is nothing in anatomy not found in this website

Electronic School of Medicine
Creator: Oluwole Ogunranti


 

   

 

 

Introduction
Cell Biology
Histology
Embryology
Gross anatomy
Organ integration
Clinical anatomy

Quiz

Dissector

Physiology

Biochemistry

Chemical Pathology

Anatomical Pathology

Pharmacology

Imaging

Medicine

Surgery

Main Subject Course Links

eAnatomy eAnesthesia eBiochemistry eChemical pathology eCommunity Health
eDermatology eENT eGynecology eHematology eImaging
eMedicine eMedical microbiology eObstetrics eOphthalmology ePathology
ePediatrics ePharmacology ePhysiology ePsychiatry    eSurgery/eOrthopedics
eLab eOSCE eProcedures eInvestigations eSchool/Videopage
eOrgans eLocator Anatomy Museum eDissector eFractures/Dissect-it-yourself
All diseases eClerking eTreatment eDoctor ePatient

 

Electronic School of Medicine
Creator: Oluwole Ogunranti