Muscles and actions of the elbow joint Dr

Muscles and actions of the elbow joint Dr. Csáki Ágnes 2017. Szeptember 27 Anatómia, szövet- és fejlődéstani intézet, SE

Articulatio cubiti

Articulatio cubiti – elbow joint compound joint: trochogynglimus humeroulnar: - trochlea humeri, - ulna trochlear notch - ginglymus -hinge - 1 axis : flexion-extension

Articulatio cubiti – elbow joint compound joint: trochogynglimus humeroradial: capitulum humeri Fovea of the radius head ball and socket joint - 3 main axises, but - subordinate role humeroulnar: - trochlea humeri, - ulna trochlear notch - ginglymus -hinge - 1 axis : flexion-extension

Articulatio cubiti – elbow joint compound joint: trochogynglimus humeroradial: capitulum humeri Fovea of the radius head ball and socket joint - 3 main axises, but - subordinate role Proximal radioulnar : ulna radial notch articular circumference of the radius - trochoid - 1 axis: pronation-supination humeroulnar: - trochlea humeri, - ulna trochlear notch - ginglymus -hinge - 1 axis : flexion-extension + Sobotta with necessarily combined joint: distal radioulnar joint

Capsula articularis membrana fibrosa Sobotta Fatty tissue membrana synovialis - fibrous layer is arises higher from the humerus Attaches to the anular ligament synovial layer atteches under the annular ligament of radius: superior sacciform recess

Capsula articularis membrana fibrosa Sobotta Fatty tissue membrana synovialis - synovial layer is attached at the border of the articular cartilage + surrounds the olecranon fossa, coronoid fossa, radial fossa;

Sobotta Thiel

Ligaments on the medial side Sobotta Thiel Ligamentum collaterale ulnare (mediale): a. pars anterior b. pars posterior c. pars transversa /lig. olecranocoronoideum (Cooper) Sobotta

Sobotta Ligaments on the lateral side Thiel Ligamentum collaterale radiale (laterale): attaches to the anular ligament Braus

Ligamentum anulare radii – prevents the dislocation of the radius In children is weaker and

CRITOE Ossification of the elbow bones capitulu m epicond. med. capitulu m Radius head 3 years old 4, 5 y. epicond. med. capitulu m olecranon trochlea Radius head 9 y.

Nursemaid’s elbow avoid the grabbing!

Movements Flexion-extension Pronation-supination

around a transverse axis (or radio-ulnar axis)through the two humeral condyles: flexion-extension (max. 140º) in the humeroulnar joint the medial condyle is lower, so the angle between the forearm and the arm is less then 180º (appr. 160º-180º) - physiological abduction (carrying angle) the trochlear notch groove is a bit "spiral", that is why the flexed forearm's hand is lateral to the shoulder

around the construction axis of the forearm (through the radius head fovea, radius neck, radius tuberosity, ulna styloid process) : pronation - supination (max. 170º) (this movement is performed by the proximal and distal radioulnar joints)

Construction axis of the upper limb 1) Caput humeri 2) Capitulum humeri 3) Tuberositas radii 4) Processus styloideus ULNAE! Flexed elbow: pronation / supination axis runs through the head and neck of radius - the distal part of radius rotates around the ulna (cca. 170 degree) Extended elbow: the whole upper limb rotates in the glenohumeral joint– (300 deg. ) construction axis and the rotation axis of the sternoclavicular joint is on the same line (– abducted és retroflected arm )( 360 deg. )

Position of the scapula 30 degrees to the frontal plane

Muscles acting on the elbow Arm flexors: Biceps brahii (biarticular) insertion by a tendon on the radial tuberosity and by aponeurosis to the antebrachial fascia flexion and supination (+abduction and anteflexion in the shoulder) Brachialis (uniarticular) insertion on the ulnar tuberosity only flexion

Muscles act on the elbow Arm extensors: Triceps brachii (biarticular) insertion on the olecranon Extension (+adduction in the shoulder)

Muscles act on the elbow Among the forearm flexors: Pronator teres and Pronator quadratus pronation Among the forearm extensors: Supinator Supination Deep branch of the radius nerve

Pronation and supination Pronator teres Pronator quadratus Supinator Biceps brachii and

Brachioradialis!! Flexion, of the elbow and from the midpositon either supination or pronation Hajdu

Bursitis olecrani

Dislocation of he ulna Thank you for your attention! References: Drake: Gray’s Anatomyfor Students, 2 nd ed. Standring: Gray’s Anatomy, 39 th ed. Radiopaedia. org