Anatomy 1 Lecture 8 - Upper extremity joints

Which joint connects the manubrium of the sternum to the clavicle?What type of joint is it?What is unique about the interjoint space?

The sternoclavicularA synovial saddle jointThere is an articualr disc between the medial end of the clavicle and sternum and the 1st costal cartilage.

Like all synovial joints, the Sternoclavicular joint has a fibrous capsule. What is unique about this joints capsule?

It is much thicker anteriorly than poteriorly

What ligament connects the clavical to the 1st rib?

The costoclavicular ligament

Sternoclavicular joint blood supply? Innervation?

Blood: internal thoracic and suprascapular arteriesNerve: branches of suprascapular and n. to subclavius

Which joint connects the acromion to the clavicle?What type of joint is this joint?What is unique about this joint?

The acromioclavicular jointIt is a synovial plane of gliding jointThe clavicle lies on top of the acromion

Which is the primary ligament involved in ths stabilization of the AC joint?What is unique about this ligament?

The acromioclavicular l. It only gives superior strength

What ligament medial to the AC joint, gives latteral stabilization of the clavicle?

The coracoclavicular ligament.The trapezoid is the more lateral portion.The conoid is more medial and attaches superiorly to the conodoi process.

AC joint Blood supply? Nerve supply

Blood: suprascapular nad thoracoacromial a.Nerve: Lateral Pectoral and Axillary n.

Which joint connects the humerus with the scapula?What type of joint is this joint?What is unique about this joint?

The glenohumeral jointSynovial ball and socket jointThe head of the humerus is much larger than the glenoid fossa. This allows for greater movement. The labrum deeps the socket, and the fibrous capsule is thin and loose allowing for maximum mobility, The capsule is acutally continuous with some of the bursae so fluid from the cavity can leave and return.

What is unique about the glenoid labrum?

It is actually attached to the long head of the biceps brachii. It deepens the socket and allows for a better fit. It forms a suction in the head of the humerus creating anegative pressure in the joint.

What are the three intrinsic ligaments of the glenohumeral joint and what do they do?

The glenohumeral ligaments, The superior, middle, and inferior (two posterior and anterior): Only on the internal aspecl of the capusle. The radiate laterally from the supraglenoid tubercle and strengthen the anterior capsule of the joint.Transverse humeral ligament: Spans the intertubercualr groove, converting it into a canal. Keeps the long head of biceps in the synovial sheath to allow for smooth movement.Coracohumeral ligament: Runs from base of the coracoid to the anatomical neck of the humerus. Strengthens the superior part of the capusle and provides a tent for the bicpes tendon to go through.

What is the point of the coracoacromial ligament?

It helps to form the coracoacromial arch which supports the prevention of superior humeral displacement.The acromion, coracoid, and the coracoacromial ligaments form the arch.

What is a bursea? And where are the usually found?

A fluid filled sac to reduce friction surrounding joints.Usually found where tendons interact with bone, ligament, or other tendons.

Which are the major bursea of the glenohumeral joint?

Subscapular bursa:between subscapularis tendon and neck of the scapula (extension of synovial capsule)Subtendinous bursa: Under the transvers humeral ligament (extension of the capsule)Subacromial bursa: Between acromion and supraspinatus tendon (extends between the deltoid an proximal end of the humerous to for the subdeltoid bursa)

From where does the glenohumeral joint receive blood supply? Nerve supply?

The posterior and anterior circumflex humeral arteriesSuprascapular, lateral pectoral, and axillary nerves

Which joints connect the ulne, radius, and humerus?What type of joints are they?

Commonly know as the cubital articulationHumeroulnar: synovial hingeHumeroradial: synovial hingeRadioulnar: synovial pivot

What are the main ligaments of the cubital articulation?

Ulnar collateral (anterior-strongest, posterior-weakest, and intermediate-oblique coopers band)Radial collateralAnnular