24 Joints (Glenohumeral)

Question 1

Which bones articulate at the glenohumeral joint?

Answer 1

The humerus and the scapula

Question 2

Describe the articulation of the glenohumeral joint

Answer 2

The proximal head of the humerus articulates with the glenoid fossa of the scapula

Question 3

Describe some of the features of the glenohumeral joint

Answer 3

At the GH joint, stability is sacrificed for mobility.

The GH joint is a ball and socket type of synovial joint, and one of the most mobile joints in the body.

The humeral head is relatively large compared to the glenoid fossa, which allows for a lot of movement but does not provide a lot of stability.

Question 4

What are the 4 ligaments that support the glenohumeral joint?

Answer 4

superior glenohumeral ligament: from supraglenoid tubercle to anatomic neck of humerus

middle glenohumeral ligament: from anterior rim of glenoid fossa to anatomic neck of humerus

inferior glenohumeral ligament: from inferior rim of glenoid fossa to anatomic neck of humerus (hammock like ligament at base of joint capsule)

coracohumeral ligament: from coracoid process to greater tubercle of humerus (blends with supraspinatus tendon)

Question 5

What are the stabilizing functions of the 4 ligaments of the glenohumeral joint?

Answer 5

superior glenohumeral ligament: restrains inferior and anterior-posterior translations of humeral head

middle glenohumeral ligament: restrains anterior movement of humerus during abducton and limits extremes of external rotation

inferior glenohumeral ligament: resists inferior and anterior-posterior translations

coracohumeral ligament: restricts inferior translation and external rotation of humeral head

Question 6

What is the coracoacromial arch?

Answer 6

Arch between the coracoid process and acromion process of the scapula, joined by the coracoacromial ligament.

Forms the ‘roof’ of the glenohumeral joint

space between coracoacromial arch and the head of the humerus is called the subacromial space (approx 1cm deep)

Question 7

What are the 3 contents of the subacromial space (betwen the coracoacromial arch and humeral head)?

Answer 7

supraspinatus muscle and tendon

tendon of long head of biceps brachii

subacromial bursa

Question 8

What are the 3 main bursa of the glenohumeral joine?

Answer 8

Subacromial bursa (in subacromial space between supraspinatus muscle and acromion process)

subdeltoid bursa (lateral extension of subacromial bursa, between deltoid and supraspinatus)

subscapular bursa (extension of synovial membrane under the coracoid process)

Question 9

Which 3 nerves innervate the glenohumeral joint?

Answer 9

axillary
suprascapular
lateral pectoral nerve