2Objectives-Describe the function of the muscles in the anterior and posterior compartment of the forearm.-Name and identify the muscles in the anterior (flexor/pronator) and posterior (extensor/supinator) compartments of the forearm, noting their relations.-Name and identify the neurovascular structures in the anterior) and posterior compartments of the forearm, noting their relations.
3Functional organization of Anterior and posterior forearm.
4Names of the Muscles of forearm Many of themLong names: good guide to location and functionLocation: ie. superficial / deepradial / ulnar(which side is the thumb on??)Function: ie. flexor / extensoradductor / abductorDoes it act on the thumb (pollux) or the fingers (digits)?
5Functional Organization Anterior compartment – flexor / pronatorPosterior Compartment – extensor / supinatorFlex the wrist ………[flexor]Extend the wrist ……..[extensor]Pronate the forearm ……..[pronator]Acting on wrist (carpus) only ……[carpi]Acting on fingers ……..[digiti / digitorum]Acting on thumb (pollux) ……[pollicus]
18Muscles of the Forearm Post View Origin :Lateral epicondyle of humerus Insertion Lateral surface of olecranon and superior part of posterior surface of ulna Action Assists triceps in extending forearm; stabilizes elbow joint; abducts ulna during pronation Innervation Radial nerve (C7, C8 and T1)AnconeusOrigin :Lateral epicondyle of humerus Insertion Lateral surface of olecranon and superior part of posterior surface of ulna Action Assists triceps in extending forearm; stabilizes elbow joint; abducts ulna during pronation Innervation Radial nerve (C7, C8 and T1) Arterial Supply Middle collateral branch of deep brachial artery Recurrent interosseous arteryRadial nerve innervates the BEST. Brachioradialis Extensors Supinator Triceps
22Rotators of the RadiusPronatorsSupinatorBiceps Brachii
23Pronation / Supination: Occurs at radio-ulnar jts.Proximal:Head of radiusarticulates with radial notch of ulna (pivot jt). It is held in place by the annular ligament.Distal – Radius pivots around the fixed distal end of ulna (pivot jt).Radio-ulnar articulation is stabilized by interosseus membrane.
25Course of radial and ulnar arteries in forearm Axillary vein:continuation of basilic vein
26Neurovasculature (deep). Lateral: radial artery radial nerve Midline: median nerveanterior interosseus a.anterior interosseus n.(deep branch of median)Medial:ulnar artery(gives off common interosseus artery divides into anterior and posterior branches)ulner nerveradial nulnar aradial a.ulnar nmedian nanterior interosseus a + n
27Radial nerve and its branches supply Neurovasculature.Radial nerve and its branches supplyall muscles in posterior compartment, including brachioradialis (!).- superficial radial nerve- deep radial nerve- posterior interosseus nerve.Posterior interosseus artery runs between superficial and deep musclesBrachioradialisDeep branchposterior interosseus branchSuperficial branch
28Lateral: radial artery radial nerve Midline: median nerve Neurovasculature.Lateral: radial arteryradial nerveMidline: median nerve[supplies all muscles exceptflexor carpi ulnaris andmedial half of flexordigitorum profundous]Medial: ulnar arteryulnar nerveradial n.Brachioradialisradial aulnar n.ulnar a.median n.
29Ulnar Nerve Medial ½ of FDP FCU All hand muscles except 11/2 muscle groups(lateral 2 lumbricals and thenar muscles )
30References Grey’s Anatomy Netter Keith Moore www.maestro.uottawa.ca Recommended reading:Clinically Oriented Anatomy,6th edition Keith MoorePages: