Deltoscapular Region, Shoulder Joint PDF

XY2141. ANATOMY. DELTOSCAPULAR REGION. SHOULDER JOINT Prepared by: Dr Viktoriia Yerokhina, Presented by: Nussrat Kazmi  MAJOR REGIONS OF THE UPPER LIMB shoulder region, which includes the pectoral, scapular, deltoid, and lateral cervical regions and overlies the pectoral (...

XY2141. ANATOMY. DELTOSCAPULAR REGION. SHOULDER JOINT Prepared by: Dr Viktoriia Yerokhina, Presented by: Nussrat Kazmi  MAJOR REGIONS OF THE UPPER LIMB shoulder region, which includes the pectoral, scapular, deltoid, and lateral cervical regions and overlies the pectoral (shoulder) girdle; axilla (axillary region) - armpit; arm (brachial region) - between the shoulder and elbow; cubital region - at the elbow; forearm (antebrachial region) - between the elbow and wrist; carpal region at the wrist hand, which has palmar and dorsal surfaces.  BONES OF THE UPPER LIMB – OSSA MEMBRI SUPERIORIS Divided into two groups: shoulder girdle and free part of the upper limb. 1. Pectoral girdle – shoulder girdle 1.1 Clavicle (clavicula) – collar bone 1.2 Scapula – shoulder blade 2. Free part of upper limb 2.1 Humerus 2.2 Ulna – elbow bone 2.3 Radius – radial bone 2.4 Bones of hand (ossa manus) 2.4.1 Carpal bones (ossa carpi) – wrist bones 2.4.2 Metacarpals (ossa metacarpi) – bones of the palm 2.4.3 Phalanges – bones of the fingers. BONES OF THE UPPER LIMB – OSSA MEMBRI SUPERIORIS  CLAVICLE – CLAVICULA L. clavicle = key S-shaped bone with a medial convexity pointing ventrally. Part of the pectoral girdle. Articulates with the scapula and the sternum It is the first bone to ossifiy, which it does by both intramembranous and endochondral ossification. Contains 3 main parts: 1. Sternal end 2. Body of clavicle 3. Acromial end  ORIENTATION OF THE CLAVICLE Sternal end is thicker and the acromial end is flat. Superior surface is smooth. Inferior surface is decorated by bony markings. Medial 2/3 have a ventral convexity. Right clavicle: A, superior aspect; B, inferior aspect. ORIENTATION OF THE CLAVICLE  CLAVICLE – CLAVICULA 1. Sternal end (extremitas sternalis) – attachment of the anterior and posterior sternoclavicular ligaments and the interclavicular ligament – origin of the sternohyoid and clavicular part of the sternocleidomastoid 1.1 Sternal facet (facies articularis sternalis) – articulates with the manubrium of the sternum 1.2 Impression for costoclavicular ligament (impressio ligamenti costoclavicularis) – attachment of the costoclavicular ligament, which connects the clavicle to the cartilage of the 1st rib.  CLAVICLE – CLAVICULA 2. Body of clavicle (corpus claviculae) – shaft of the clavicle – origin of the clavicular part of pectoralis major 2.1 Subclavian groove (sulcus musculi subclavii) – a shallow groove on the caudal surface of the shaft for the insertion of the subclavius  CLAVICLE – CLAVICULA 3. Acromial end (extremitas acromialis) – origin of the clavicular part of the deltoid and the insertion of the trapezius 3.1 Acromial facet (facies articularis acromialis) – articulates with the acromion 3.2 Coracoclavicular tuberosity – a large bony protuberance – has two parts: conoid tubercle and trapezoid line 3.2.1 Conoid tubercle (tuberculum conoideum) – attachment the conoid ligament 3.2.2 Trapezoid line (linea trapezoidea) – attachement of the trapezoid ligament – conoid ligament and trapezoid ligament form the coracoclavicular ligament MUSCLES AND LIGAMENTS ATTACHED TO THE CLAVICLE  CLAVICLE FRACTURES Common fractures that usually affect children and adolescents and typically occur from a direct fall onto the shoulder. Clavicle fractures are classified according to the fracture location with the use of the Allman classification. More than 2/3 of cases are due to a fracture in the middle third of the clavicle (group I of the Allman classification). Nonspecific symptoms: swelling, focal tenderness, and reduced movement of the arm Specific signs: shortening and drooping of the shoulder can occur. X-ray is routinely performed to confirm the diagnosis. Treatment depends on the location of the fracture and includes conservative and/or surgical measures.  SCAPULA – SCAPULA A flat triangular bone that connects to the posterior aspect of the thorax by muscles at the level of the 2nd to 7th rib. It is part of the pectoral girdle and features a large dorsal spine, which ends laterally as the acromion. Right scapula  SCAPULA - SHOULDER BLADE 1. Two surfaces: a) costal / anterior b) dorsal. 2. Three borders: a) superior, b) lateral, c) medial. 3. Three angles: a) inferior, b) superior, c) lateral. SUBDIVISIONS OF THE COSTAL SURFACE OF SCAPULA 4.1 Subscapular fossa (fossa subscapularis) – origin of the subscapularis  SUBDIVISIONS OF THE POSTERIOR SURFACE OF SCAPULA 5.1 Spine of scapula (spina scapulae) - the most prominent feature of the posterior scapula. It runs transversely across the scapula, dividing the surface into two. 5.1.1 Deltoid tubercle (tuberculum deltoideum) – located between the insertion of the trapezius and the origin of the deltoid muscle  SCAPULA - SHOULDER BLADE 5.2 Acromion – lateral extension of the spine of the scapula 5.2.1 Clavicular facet (facies articularis clavicularis) – articulates with the clavicle 5.3 Supraspinous fossa (fossa supraspinata) – area above the spine 5.4 Infraspinous fossa (fossa infraspinata) – area below the spine of the scapula.  SCAPULA - SHOULDER BLADE 6. Glenoid cavity (cavitas glenoidalis) – articular fossa of the shoulder joint 6.1 Supraglenoid tubercle (tuberculum supraglenoidale) – located just above the glenoid cavity 6.2 Infraglenoid tubercle (tuberculum infraglenoidale) – located just below the glenoid cavity  SCAPULA - SHOULDER BLADE 7. Neck of scapula (collum scapulae) – narrowed area between the glenoid cavity and the rest of the scapula – attachment of the articular capsule of the shoulder joint 8. Coracoid process (processus coracoideus) – origin of the coracobrachialis and the short head of the biceps brachii – insertion of the pectoralis minor – attachment of the coraco-acromial ligament, coracoclavicular ligament and coracohumeral ligament 8 7  SCAPULA - SHOULDER BLADE 9. Suprascapular notch (incisura scapulae) – notch on the superior border next to the coracoid process – suprascapular nerve runs through the notch under the ligament – suprascapular artery and vein pass over the ligament 10. Spinoglenoid notch (incisura spinoglenoidalis) – notch between the glenoid cavity and the spine of the scapula – transmits the suprascapular nerve and vessels SCAPULA - SHOULDER BLADE  HUMERUS – HUMERUS A long bone of the free upper limb. It is divided into a head, a shaft and a condyle. Head of the humerus is a component of the shoulder joint. Two projections, the greater and lesser tubercle, are located on the head and serve as insertion sites for the rotator cuff muscles. Radial nerve and the deep brachial artery run around the shaft of the humerus in a groove on the posterior surface called the radial groove. Distal end of the humerus is called the condyle of the humerus. It is a component of the elbow joint. It posses a medial and lateral epicondyle, which serve as origin sites for the muscles of the forearm.  HUMERUS 1. Head (caput humeri) – articular head of the shoulder joint 1.1 Anatomical neck (collum anatomicum) - attachment of the articular capsule of the shoulder joint 1.2 Greater tubercle (tuberculum majus) – projects dorslaterally from the head 1.2.1 Crest of greater tubercle (crista tuberculi majoris) – the insertion of the pectoralis major 1.3 Lesser tubercle (tuberculum minus) – projects ventromedially from the head 1.3.1 Crest of lesser tubercle (crista tuberculi minoris) – the insertion of the teres major and lati ssimus dorsi 1.4 Intertubercular sulcus (sulcus intertubercularis) – groove between the greater and lesser tubercles HUMERUS  HUMERUS 2. Surgical neck (collum chirurgicum) – a narrow part of the humerus located below the head 3. Shaft of humerus (corpus humeri) – body of the humerus 3.1 Deltoid tuberosity (tuberositas deltoidea) – insertion of the deltoid muscle 3.2 Radial groove (sulcus nervi radialis) – oblique groove for the radial nerve and the deep brachial vessels – located on the posterior surface of the shaft 3.3 Nutrient foramen (foramen nutricium) – entrance of vessels into the medullary cavity.  HUMERUS Surfaces: 3.4 Anteromedial surface (facies anteromedialis) 3.5 Anterolateral surface (facies anterolateralis) 3.6 Posterior surface (facies posterior) Margins: 3.7 Medial border (margo medialis) 3.8 Lateral border (margo lateralis) 4. Condyle of humerus (condylus humeri) – widened distal end of the humerus Anterior aspect of the right humerus.  HUMERUS 4. Condyle of the humerus (condylus humeri) – widened distal end of the humerus 4.1 Medial supraepicondylar ridge (crista supraepicondylaris medialis) 4.2 Lateral supraepicondylar ridge (crista supraepicondylaris lateralis) 4.3 Medial epicondyle (epicondylus medialis) 4.3.1 Groove for ulnar nerve (sulcus nervi ulnaris) 4.4 Lateral epicondyle (epicondylus lateralis)  HUMERUS Anterior aspect of the right humerus.  HUMERUS 4.5 Capitulum (capitulum humeri) – articular head of the humeroradial joint 4.6 Trochlea (trochlea humeri) – articular head of the humeroulnar joint 4.7 Olecranon fossa (fossa olecrani) – located dorsally on the condyle of the humerus – contains the olecranon of the ulna when the forearm is extended  HUMERUS Posterior aspect of the humerus.  HUMERUS 4.8 Coronoid fossa (fossa coronoidea) – located ventromedially on the condyle of the humerus – contains the coronoid process of the ulna when the forearm is flexed 4.9 Radial fossa (fossa radialis) – located ventrolaterally on the condyle of the humerus – contains the head of the radius when the forearm is flexed JOINTS OF THE SHOULDER GIRDLE  JOINTS OF THE UPPER LIMB – JUNCTURAE MEMBRI SUPERIORIS The vast majority of the joints of the upper limb are synovial joints. 1. Sternoclavicular joint (articulatio sternoclavicularis) 2. Acromioclavicular joint (articulatio acromioclavicularis) 3. Glenohumeral joint / shoulder joint (articulatio humeri/glenohumeralis) 4. Elbow join (articulatio cubiti) 5. Radio-ulnar syndesmosis (syndesmosis radioulnaris) 6. Distal radio-ulnar joint (articulatio radioulnaris distalis) 7. Wrist joint (articulatio radiocarpalis) 8. Joints of hand (articulationes manus)  STERNOCLAVICULAR JOINT – ARTICULATIO STERNOCLAVICULARIS A complex joint that allows only very limited movements. It cooperates with the other joints of the pectoral girdle.  STERNOCLAVICULAR JOINT – ARTICULATIO STERNOCLAVICULARIS 1. Type: complex 2. Shape: ball-and-socket 3. Articular head: sternal facet of the clavicle 4. Articular fossa: clavicular notch on the sternum 5. Capsule: attached to the circumferences of the articular surfaces 6. Ligaments: 6.1 Anterior and posterior sternoclavicular ligament (l. sternoclaviculare anterius et posterius) 6.2 Interclavicular ligament (l. interclaviculare) 6.3 Costoclavicular ligament (l. costoclaviculare) 7. Accessory features: articular disc 8. Movements: very limited in all directions  ACROMIOCLAVICULAR JOINT – ARTICULATIO ACROMIOCLAVICULARIS A simple plane joint that allows only a limited degree of movement. It variably contains an articular disc. It cooperates with the other joints of the pectoral girdle in producing movements of the upper limb.  ACROMIOCLAVICULAR JOINT – ARTICULATIO ACROMIOCLAVICULARIS 1. Type: simple 2. Shape: plane 3. Articular surfaces: 3.1 Clavicular facet of the acromion (facies articularis clavicularis acromii) 3.2 Acromial facet of the clavicle (facies articularis acromialis claviculae) 4. Capsule: firm, attached to the circumference of articular surfaces 5. Accessories: articular disc is present in 50% of the population  ACROMIOCLAVICULAR JOINT – ARTICULATIO ACROMIOCLAVICULARIS 6. Ligaments: 6.1 Acromioclavicular ligament (l. acromioclaviculare) 6.2 Coraco-acromial ligament (l. coracoacromiale) 6.3 Coracoclavicular ligament (l. coracoclaviculare) 6.3.1 Trapezoid ligament (l. trapezoideum) 6.3.2 Conoid ligament (l. conoideum) 7. Movements: very limited in all directions  SHOULDER/ GLENOHUMERAL JOINT – ARTICULATIO HUMERI/GLENOHUMERALIS A ball-and-socket joint with the greatest extent of movement of all the joints of the human body. It allows movements in all three planes. The incongruity between the shallow articular fossa and the large articular head inflicts great instability on the joint. This is compensated by the rotator cuff muscles which attach to the head of the humerus and hold it firmly in the articular fossa of the scapula.  SHOULDER/ GLENOHUMERAL JOINT – ARTICULATIO HUMERI/ GLENOHUMERALIS 1. Type: simple 2. Shape: ball-and-socket 3. Articular head: head of the humerus 4. Articular fossa: glenoid cavity of the scapula 5. Capsule: attaches to the neck of the scapula and the anatomical neck of the humerus SHOULDER/GLENOHUMERAL JOINT – ARTICULATIO HUMERI/GLENOHUMERALIS  LIGAMENTS OF SHOULDER / GLENOHUMERAL JOINT 6.1 Coracohumeral ligament (ligamentum coracohumerale) – runs from the coracoid process of the scapula to the greater tubercle of the humerus 6.2 Glenohumeral ligaments (ll. glenohumeralia) – three capsular ligaments – superior, middle, inferior – run through the fibrous layer of the articular capsule  LIGAMENTS OF SHOULDER / GLENOHUMERAL JOINT 6.3 Coraco-acromial ligament (l. coracoacromiale) – lies above the joint between the coracoid process and acromion 6.4 Transverse humeral ligament (l. transversum humeri) – runs over the greater and lesser tubercle of the humerus – bridges the intertubercular sulcus, holding the tendon of the long head of the biceps brachii firmly in place LIGAMENTS OF SHOULDER / GLENOHUMERAL JOINT  RANGE OF MOTION OF THE SHOULDER Movements: large range of joint motion in all three planes Flexion and extension Medial and lateral rotation Abduction and adduction  CLINICAL CORRELATION Dislocation (subluxation) of the shoulder joint occurs usually in the antero-inferior direction because of the lack of support by tendons of the rotator cuff. It may damage the axillary nerve and the posterior humeral circumflex vessels. Referred pain to the shoulder most probably indicates involvement of the phrenic nerve (or diaphragm). Supraclavicular nerve (C3–C4), which supplies sensory fibers over the shoulder, has the same origin as the phrenic nerve (C3–C5), which supplies the diaphragm. Examples of referred pain are gallbladder pain radiating to right shoulder and splenic pain radiating to left shoulder.  MUSCLES OF THE UPPER LIMB – MUSCULI MEMBRI SUPERIORIS Muscles of the upper limb proper include: muscles of the shoulder joint, muscles of the arm, muscles of the forearm hand muscles.  MUSCLES OF THE SHOULDER JOINT Surround the shoulder joint. Supraspinatus, infraspinatus, teres minor and subscapularis form the rotator cuff, which allows rotation of the humerus at the shoulder joint, provides stability to the shoulder and prevents dislocation. 1. Deltoid (m. deltoideus) 2. Supraspinatus (m. supraspinatus) 3. Infraspinatus (m. infraspinatus) 4. Teres major (m. teres major) 5. Teres minor (m. teres minor) 6. Subscapularis (m. subscapularis)  DELTOID (MUSCULUS DELTOIDEUS) – multipennate muscle Origin: 1. Spinal/posterior part: scapula – lateral 2/3 of the spine of the scapula 2. Acromial part: scapula – acromion 3. Clavicular/anterior part: clavicle – lateral 1/3 Insertion: humerus – deltoid tuberosity  DELTOID (MUSCULUS DELTOIDEUS) Function: muscle working as whole presses the head of the humerus into the articular fossa of the shoulder joint and therefore increases stability of the shoulder joint 1. Spinal part (pars spinalis): dorsal flexion and external rotation of the arm 2. Acromial part (pars acromialis): abduction of the arm 3. Clavicular part (pars clavicularis): ventral flexion, abduction and internal rotation of the arm Innervation: axillary nerve (C5 and C6)  SUPRASPINATUS (MUSCULUS SUPRASPINATUS) INFRASPINATUS (MUSCULUS INFRASPINATUS) Supraspinatus (m. supraspinatus) O: scapula – supraspinous fossa I: humerus – greater tubercle F: initial abduction and external rotation of the arm, stabilisation of the head of the humerus in the articular fossa of the shoulder joint N: suprascapular nerve (C5) Infraspinatus (m. infraspinatus) O: scapula – infraspinous fossa I: humerus – greater tubercle F: adduction and external rotation of the arm N: suprascapular nerve (C5 and C6).  TERES MINOR (MUSCULUS TERES MINOR) TERES MAJOR (MUSCULUS TERES MAJOR) Teres minor (musculus teres minor) O: scapula – cranial 2/3 of the lateral border I: humerus – greater tubercle F: adduction and external rotation of the arm N: axillary nerve (V5, variably C4–C6) Teres major (musculus teres major) O: scapula – caudal 1/3 of the lateral border I: humerus – crest of the lesser tubercle F: adduction, dorsal flexion and internal rotation of the arm N: subscapular nerve (C6)  SUBSCAPULARIS (MUSCULUS SUBSCAPULARIS) Subscapularis (musculus subscapularis) O: scapula (costal surface) – muscular lines I: humerus – lesser tubercle F: adduction and internal rotation of the arm N: subscapular nerve (C5 and C6)  ROTATOR CUFF group of four muscles that attach to the greater and lesser tubercle of the humerus they stabilise the shoulder joint and aid in its rotation 1. Supraspinatus – inserts on the superior facet of the greater tubercle 2. Infraspinatus – inserts on the middle facet of the greater tubercle 3. Teres minor – inserts on the inferior facet of the greater tubercle 4. Subscapularis – inserts on the lesser tubercle REFERENCES