Composite muscle

Composite or hybrid muscles are those muscles which have more than one set of fibers but perform the same function and are usually supplied by different nerves for different set of fibers.[1][2]

Examples
  • Brachialis: Musculocutaneous nerve is motor and radial nerve is proprioceptive.
  • Adductor magnus : Its adductor part by posterior division of obturator nerve and hamstring part by tibial part of sciatic nerve.
  • Biceps femoris: Its long head is supplied by the tibial part of sciatic nerve, whereas the short head is supplied by the common peroneal nerve. This reflects the composite derivation from the flexor and extensor musculature.
  • Pectineus: Its anterior set of fibers are supplied by the femoral nerve, whereas posterior set of fibers are supplied by the obturator nerve.
  • Flexor digitorum profundus: Its radial half of is supplied by the median nerve and the ulnar half is supplied by the ulnar nerve.
  • Trapezius: Its motor fibres are supplied by the spinal accessory nerve and proprioception is carried by C3 and C4 dorsal rami.
  • Iliopsoas: It is a composite muscle performing flexion at the hip.
  • The tongue is a composite muscle made up of various components like longitudinal, transverse, horizontal muscles with different parts innervated having different nerve supply.
  • Digastric muscle: Its anterior belly is supplied by nerve to mylohyoid (a branch of trigeminal nerve). The posterior belly is supplied by the facial nerve.

Commonly confused

Certain muscles are commonly confused with composite muscles which they are not. Examples are:

  • Rectus femoris
  • Omohyoid
  • Occipitofrontalis
  • Ligament of Trietz

References
  1. Cartmill, Matt (1987). Human Structure. Harvard University Press. p. 2. ISBN 978-0-674-41805-9.
  2. Chitguppi, Dr. Rajeev (1 January 2010). Elsevier Comprehensive Guide To Pgdee Basic Sciences. Elsevier India Pvt. Limited. pp. 49–. ISBN 978-81-312-2380-2.
  • Cunningham's textbook of anatomy (old edition)
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.