UE Arthrology

Question 1

What are the joints that comprise the shoulder girdle?

What are their classifications?

Answer 1

• sternoclavicular joint: sellar synovial joint (saddle joint), between the clavicular notch of the manubrium and sternal facet on sternal end of the clavicle
• acromioclavicular joint: planar synovial joint, between the acromial facet on the acromial end of the clavicle and the facet on the acromion of the scapula
• glenohumeral joint: spheroidal synovial joint, between the glenoid cavity of the scapular head, which is deepened and supported by the glenoid labrum and the head of the humerus

Question 2

What are the components of the sternoclavicular joint?

Answer 2

• articular capsule (surrounds the joint): fibrous capsule and synovial membrane
• articular disc
• costoclavicular L.: from sternal end of clavicle to 1st rib
• anterior sternoclavicular L.: thickened fibrous capsule on anterior aspect
• interclavicular L.: from sternal end of clavicle to contralateral clavicle

Question 3

What are the components of the acromioclavicular joint?

Answer 3

• articular capsule (sleeve like, surrounds the joint): fibrous capsule and synovial membrane
• articular disc
• acromioclavicular L.: from acromion to clavicle
• coracoclavicular L. (two bands uniting the coracoid process and the clavicle): trapezoid L. (nearly horizontal band from trapezoid line to coracoid process, lateral to conoid L.) and conoid L. (vertical, inverted triangular band from conoid tubercle to coracoid process, medial to trapezoid L.)

Question 4

What are the components of the glenohumeral joint?

Answer 4

• glenoid labrum
• articular capsule (loose, surrounds the joint): fibrous capsule (open in two places to allow passage of the long head of biceps T. and communication w/ the subscapular bursa) and the synovial membrane (lines the fibrous capsule, communicates w/ the subscapular bursa, forms a sheath around the long head of the biceps brachii T. in the intertubercular groove)
• glenohumeral L.: from glenoid labrum and supraglenoid tubercle to the anatomical humeral neck blending w/ the fibrous capsule
• coracohumeral L.: from the base of the coracoid process to the anterior edge of the greater tubercle of the humerus
• transverse humeral L.: broad band from the greater humeral tubercle to lesser humeral tubercle spanning the intertubercular groove; encapsulates the long head of the biceps brachii T.
• coracoacromial arch (osseoligamentous arch preventing superior displacement of the humerus from the glenoid cavity): coracoacromial L. (from coracoid process to acromion)

Question 5

What bursae are present in the glenohumeral joint?

Answer 5

• subscapular bursa: between the subscapularis T. and the scapular neck, communicates w/ the synovial membrane of the glenohumeral joint
• subacromial bursa: between the deltoid M., supraspinatus T., and the articular capsule; does not usually communicate w/ the synovial membrane

Question 6

The _____________ joint is susceptible to injury and separation, often referred to as “shoulder separation,” and is capable of separating with or w/o rupture of the coracoclavicular L.

Answer 6

acromioclavicular joint

Question 7

The _____________ joint is susceptible to dislocation due to its mobility and relative instability. Due to the presence of the coracoacromial arch, dislocation of this joint most commonly occurs anterioly or inferiorly

Answer 7

glenohumeral joint

Question 8

What type of joint is the elbow?

What is the capsule type?

What are the names of the subjoints?

What articulations are involved?

Answer 8

• ginglymus synovial joint
• articular capsule: fibrous capsule and synovial membrane (continuous distally w/ the synovial membrane of the proximal radioulnar joint)
• humeroulnar joint and humeroradial joint
• articulations between the humeral condyle, the trochlear notch of the ulna, and the head of the radius

Question 9

• joint within the elbow
• trochlear notch of ulna wraps around humeral trochlea
• ulnar collateral L. of the elbow (from the medial humeral epicondyle to the coronoid process of the ulna and olecranon, consists of three bands): anterior band (cord shaped, strongest), posterior band (fan shaped, weakest), and oblique band (deepends socket for humeral trochlea)

Answer 9

humeroulnar joint

Question 10

• joint within the elbow
• humeral capitulum articulates w/ the fovea of the radial head
• radial collateral L. of the elbow: fan shaped, from the lateral humeral epicondyle to blend w/ the annular L. of the radial head

Answer 10

humeroradial joint

Question 11

What are the bursae present in the elbow joint?

Answer 11

• olecranon bursae: subtendinous (between triceps brachii T. and olecranon), intratendinous (inside the triceps brachii T.), and subcutaneous (in the subcutaneous connective tissue over the olecranon)
• subcutaneous bursa of the medial humeral epicondyle
• subcutaneous bursa of the lateral humeral epicondyle
• bursa of the anconeus: between the lateral humeral epicondyle and anconeus M.
• bursa at origin of extensor carpi radialis brevis: between the lateral humeral epicondyle and the extensor carpi radialis brevis M.
• bicipitoradial bursa: between the biceps brachii T. and the radial tuberosity

Question 12

• injury of the elbow in response to force transmitted along the long axis of forearm
• usually involves a tear in the ulnar collateral L.

Answer 12

posterior elbow dislocation

Question 13

What are the two more common elbow bursae to become inflammed?

Answer 13

• subcutaneous olecranon bursa and bicipitoradial bursa
• subcutaneous is sometimes called “student’s elbow”, “dart thrower’s elbow”, and “miner’s elbow”
• results from excessive friction between the skin and the olecranon

Question 14

What are the 3 subjoints or articulations within the radioulnar joint?

Answer 14

• proximal radioulnar joint: trochoid synovial joint, primary site of supination and pronation
• middle radioulnar joint: syndesmosis
• distal radioulnar joint: trochoid synovial joint, L shaped joint between the head of the ulna and the ulnar notch of the radius laterally and the articular disc inferiorly

Question 15

What are the components of the proximal radioulnar joint?

Answer 15

(trochoid synovial joint, primary site of supination/pronation)

• articular capsule (continues w/ the articular capsule of the elbow joint): fibrous capsule and synovial membrane (continues w/ the synovial membrane of elbow joint, lines the underside of the annular L., continues distally as the sacciform recess*)
• annular L.: from coronoid process of the ulna around the radial head to insert back on the ulna, holds the radial head in the radial notch

*sacciform recess: small pocket of synovial membrane protruding out from under the annular L.

Question 16

What are the components of the middle radioulnar joint?

Answer 16

(syndesmosis)

• oblique cord: between the coronoid process of the ulna and radial body
• interosseous membrane: between length of ulna and radius, divides the forearm into anterior and posterior compartments, serves as muscular attachments, does not limit pronation/supination

Question 17

What are the components of the distal radioulnar joint?

Answer 17

(trochoid synovial joint, L shaped between the head of the ulna and the ulnar notch of the radius laterally and the articular disc inferiorly)

• articular capsule (surrounds the joint): fibrous capsule (deficient superiorly), synovial membrane (lines the fibrous capsule, extends proximally out from under the fibrous capsule as sacciform recess* of the distal radioulnar joint), and articular disc

*sacciform recess: small pocket of synovial membrane protruding out from under the fibrous capsule

Question 18

The ______ head is capable of being dislocated out of the annular L. to varying degrees. This injury typically occurs from pulling on the arm of a child, sometimes called “nursemaid’s elbow” or “pulled elbow”

Answer 18

radial

Question 19

• wrist joint: condylar synovial joint, between the distal end of the radius, plus the articular disc of the distal radioulnar joint and the scaphoid, lunate, and triquetrum bones
• articular capsule (surrounds the joint): fibrous capsule (from radius and ulna to proximal row of carpal bones), synovial membrane (lines the fibrous capsule, folds), and articular disc

Answer 19

radiocarpal joint

Question 20

What are the ligaments of the radiocarpal joint?

Answer 20

• palmar radiocarpal L. (two bands: one from the radius across to the scaphoid, and to the lunate, the other is from the radius to the capitate)
• dorsal radiocarpal L. (oblique band from the radius across the lunate to the triquetrum)
• palmar ulnocarpal L. (two bands: one from the ulnar head to the lunate, the other from the ulnar head to the triquetrum)
• dorsal ulnocarpal L. (from the ulnar head to the triquetrum)
• radial collateral L. of the wrist (from radial styloid process to scaphoid)
• ulnar collateral L. of the wrist (from ulnar styloid process to triquetrum, via the pisiform)

Question 21

What are the components of the intercarpal joints?

Answer 21

(planar synovial joints: scapholuntae, lunotriquetrum, pisotriquetrum, pisohamate, trapeziotrapezoid, capitiohamate, trapeziocapitate)

• articular capsule (continuous, common joint space between all intercarpal and carpometacarpal joints except the 1st carpometacarpal joint): fibrous capsule (surrounds joint) and synovial membrane (lines the fibrous capsule)
• posterior intercarpal L. (between carpal bones posteriorly)
• anterior intercarpal L. (between carpal bones anteriorly)
• interosseous intercarpal L. (in the joint space between carpal bones)
• pisiform joint (articulation of the pisiform with the anterior surface of the triquetrum): pisohamate (between the pisiform and the hook of the hamate)

Question 22

What are the components of midcarpal joint?

Answer 22

(sellar synovial joint, between proximal and distal rows of carpal bones)

• articular capsule (continuous w/ the capsule of the intercarpal and carpometacarpal joints, surrounding a common joint cavity, strengthened anteriorly and posteriorly by the anterior and posterior intercarpal L., strengthened medially and laterally by the radial and ulnar collateral L. of the wrist), fibrous capsule (surrounds the joint), and synovial membrane (lines the fibrous capsule)

Question 23

What are the components of the 1st carpometacarpal joint?

Answer 23

(sellar synovial joint, from trapezium to 1st metacarpal)

• articular capsule (separate from the common joint capsule and space of the medial four carpometacarpal joints): fibrous capsule (surrounds joint) and synovial membrane (lines fibrous capsule)
• palmar carpometacarpal L.
• dorsal carpometacarpal L.

Question 24

What are the components of the 2nd-5th carpometacarpal joints?

Answer 24

(planar synovial joint, from distal carpal row to 2nd-5th metacarpals)

• articular capsule (common joint capsule and space for the medial four carpometacarpal joints): fibrous capsule (surrounds joint) and synovial membrane (lines fibrous capsule)
• palmar carpometacarpal L.
• dorsal carpometacarpal L.
• pisometacarpal L. (a/w 5th metacarpal, in junction w/ pisohamate L., are the continuation of the flexor carpi ulnaris T.)
• radiate carpal L. (from the capitate to the bases of metacarpals)

Question 25

What are the components of the intermetacarpal joints?

Answer 25

(**4, planar synovial joints**) - **articular capsule** (between the bases of the 1st and 2nd metacarpal bones, separate from the medial three joints that share a joint capsule and cavity w/ the medial four carpometacarpal joints): **fibrous capsule** and **synovial membrane** - **dorsal intermetacarpal L.** - **palmar intermetacarpal L.** - **interosseous intermetacarpal L.** (inside the joint space between bases of metacarpal bones)

Question 26

What are the components of the metacarpophalangeal joints?

Answer 26

(**5, condylar synovial joints**) - **articular capsule** (separate for each metacarpophalangeal joint): **fibrous capsule** and **synovial membrane** - **palmar L.** (or **plate L.**; thickened anterior aspect of the articular capsule, attachment point for the fan shaped part of the collateral L., blends w/ the digital sheath providing a longitudinal groove for the flexor tendons to glide and stay over the center of the joint) - **medial collateral L.** (medial side of the joint, possesses a cord shaped part running proximal to distal and a fan shaped part traveling anteriorly to insert onto the palmar L.) - **lateral collateral L.** (lateral side of the joint, possesses a cord shaped part running proximal to distal and a fan shaped part traveling anteriorly to insert onto the palmar L.) - **deep transverse metacarpal L.** (transverse fibers joining the palmar L. of the medial four metacarpophalangeal joints)

Question 27

Sprain of the ______ \_\_\_\_\_\_\_ ligament, and even **avulsion** of the **lateral** part of the **proximal phalanx** of the **thumb** is an injury common to individuals who ride a mechanical bull, and is therefore known as **"bull rider's thumb"**

Answer 27

lateral collateral L.

Question 28

Laxity or rupture of both _______ \_\_\_\_\_\_\_\_\_ of the 1st ______________ joints results in a **hyperabduction** of that joint and is referred to as **"skier's thumb"** or **"game keeper's thumb"**

Answer 28

- collateral ligaments - 1st metacarpophalangeal joints

Question 29

What are the components of the 1st interphalangeal joint?

Answer 29

(**ginglymus synovial joint**) - articular capsule: fibrous capsule and synovial membrane - **palmar L.** (or plate L., thickened anterior aspect of the articular capsule, attachment point for the fan shaped part of the collateral L., blends w/ the digital sheath providing a longitudinal groove for the flexor tendons to glide and stay over the center of the joint) - **medial collateral L.** (medial side of the joint, possesses a cord shaped part running proximal to distal and a fan shaped part traveling anteriorly to insert onto the palmar L.) - **lateral collateral L.** (lateral side of the joint, possesses a cord shaped part running proximal to distal and a fan shaped part traveling anteriorly to insert on the palmar L.)

Question 30

What are the components of the proximal interphalangeal joints?

Answer 30

(**4, ginglymus synovial joint**, union between 2nd-5th proximal and intermediate phalanges) - articular capsule (separate for each joint): fibrous capsule and synovial membrane - **palmar L. (or plate L.)** - **medial collateral L.** - **lateral collateral L.** \*descriptions of Ls. are the same as the 1st interphalangeal joint\*

Question 31

What are the components of the distal interphalangeal joints?

Answer 31

(**4, ginglymus synovial joint**, union between 2nd-5th intermediate and distal phalanges) - articular capsule (separate for each joint): fibrous capsule and synovial membrane - **palmar L. (or plate L.)** - **medial collateral L.** - **lateral collateral L.** \*descriptions of Ls. are the same as the 1st interphalangeal joint\*

Question 32

Sudden **hyperflexion** of the _____ \_\_\_\_\_\_\_\_\_\_\_\_ joint can avulse the attachment of the **long extensor tendon** w/ that tendon away from the **distal phalanx**, this is known as **"mallet finger"** or **"baseball finger"**

Answer 32

distal interphalangeal joint

Question 33

What are the scapular movements of the UE?

Answer 33

- elevation/depression of scapula - protraction/retraction of scapula - rotating the glenoid cavity up/down

Question 34

What are the glenohumeral movements of the UE?

Answer 34

- extension (posteriorly) and flexion (anteriorly) of the arm - hyperextension (posterior to anatomical position) of the arm - abduction (away from midline) and adduction (toward midline) of the arm - medial and lateral rotation

Question 35

What are the elbow movements of the UE?

Answer 35

- flexion (anteriorly) and extension (posteriorly) of the forearm

Question 36

What are the radioulnar movements of the UE?

Answer 36

- pronation (thumb facing medially) - supination (thumb facing laterally, anatomical position)

Question 37

What are the wrist movements of the UE?

Answer 37

- extension (posteriorly) and flexion (anteriorly) of the hand - ulnar flexion (medial movement of the hand at the wrist) - radial flexion (lateral movement of the hand at the wrist)

Question 38

What are the digits 2-5 movement of the UE?

Answer 38

- extension (posteriorly) and flexion (anteriorly) - abduction (movement away from middle finger) and adduction (movement toward middle finger), the 3rd finger can be abducted medially or laterally but cannot be adducted

Question 39

What are the thumb movements of the UE?

Answer 39

- extension (lateral movement from anatomical position) and flexion (sweeping thumb across the palmar surface) - abduction (anterior movement from anatomical position) and adduction (posterior movement from abducted position) - opposition (touching thumb to 5th digit) and reposition (returning the thumb from opposed position)

Question 40

What fascia is present in the shoulder and axilla?

Answer 40

- **pectoral fascia** (invests the pectoralis major M., continuous superiorly w/ deltoid fascia, laterally w/ axillary fascia, and inferiorly w/ abdominal deep fascia - **axillary fascia** (floor of the axilla, continuous medially w/ pectoral fascia and inferiorly w/ clavipectoral fascia) - **clavipectoral fascia** (deep to pectoral fascia and pectoralis M., extends inferiorly from the clavicle to invest the subclavius and pectoralis minor M. before blending w/ axillary fascia): **costocoracoid membrane** (clavipectoral fascia between the subclavius M. and pectoralis minor M.) and **suspensory L. of the axilla** (clavipectoral fascia between pectoralis minor M. and axillary fascia, forms axillary fossa - **deltoid fasica** (covers the deltoid M., continuous anteriorly w/ pectoral fascia and posteriorly w/ infraspinous fascia - **supraspinous fascia** (extremely dense fascia overlying the supraspinatus M.) - **infraspinous fascia** (extremely dense fascia overlying the infraspinatus M.)

Question 41

What fascia is present in the brachium?

Answer 41

- **brachial fascia** (continuous superiorly w/ the pectoral, deltoid, infraspinous, and axillary fascia, continuous inferiorly w/ antebrachial fascia, covers the musculature of the brachium) - **medial intermuscular septum** (extends from the deep surface of brachial fascia to the humerus, distally to the medial supraepicondylar ridge, in conjunction w/ the lateral intermuscular septum, separates the brachium into an anterior (flexor) and posterior (extensor) compartment - **lateral intermuscular septum** (extends from the deep surface of brachial fascia to the humerus, distally to the lateral supraepicondylar ridge)

Question 42

What fascia is present in the antebrachium?

Answer 42

- **antebrachial fascia** (continuous superiorly w/ brachial fascia, utilizes the interosseous membrane to divide the antebrachium into an anterior (flexor) and posterior (extensor) compartment - **interosseous membrane** - **extensor retinaculum** and **synovial tendon sheaths** - **palmar carpal L.** (corresponding anterior transverse focal thickening of antebrachial fascia, continuous w/ the extensor retinaculum - **flexor retinaculum** and **common flexor sheath**

Question 43

Describe the extensor and flexor retinaculums of the UE and associated structures:

Answer 43

- **extensor retinaculum** (transverse focal thickening of antebrachial fascia, holds the extensor tendons in position): **synovial tendon sheaths** (6 synovial tendon sheaths surround the long extensor tendons of the forearm as they pass under the extensor retinaculum to reduce friction) - **flexor retinaculum** (**transverse carpal L.**, deep and distal to the palmar carpal L., fibrous band extending from the tubercles of the scaphoid and trapezium across the carpal arch to the hook of the hamate and pisiform, forming the carpal tunnel): **common flexor sheath** (1 large synovial sheath surrounding the long tendons of the flexor digitorum superficialis and profundus M. to reduce friction under the flexor retinaculum)

Question 44

What fascia is present in the hand?

Answer 44

- **palmar fascia** (continuous proximally w/ antebrachial fascia) - **palmar aponeurosis** (thickened central region of palmar fascia, continuous proximally w/ the palmaris longus T.): s**uperficial transverse metacarpal L.** (base of the palmar aponeurosis), **retinacula cutis** (numerous small ligaments that extend from the palmar aponeurosis to the skin, restricting palmar skin movement), **medial fibrous septum** (extends dorsally to the 5th metacarpal, separates the hypothenar compartment from the central compartment), and l**ateral fibrous septum** (extends dorsally to the 3rd metacarpal, separates the thenar compartment from the central compartment) - **dorsal fascia** (deep to subcutaneous fat on the dorsum of the hand) - **fibrous digital sheaths** (distal extensions from the palmar aponeurosis, fibrous tubes that enclose the synovial sheaths of the long flexor tendons, arranged into altering annular and cruciform segments): **digital synovial sheaths** (synovial sheaths for the individual digits that surround the long tendons of the flexor digitorum superficialis and profundus M., held firmly in place by the fibrous digital sheaths

Question 45

What are the compartments of the hand? (5)

Answer 45

- **hypothenar compartment**: contains the hypothenar muscles - **central compartment**: contains the flexor tendons, the lumbrical muscles, superficial palmar arterial arch, digital vessels, and digitals nerves - **thenar compartment**: contains thenar muscles - **adductor compartment**: contains the adductor pollicis M. - **interosseous compartment**: between the metacarpal bones, contains the interossei muscles

Question 46

- irritation of the synovial sheaths can cause an accumulation of mucopolysaccharide fluid that can form an usually painless lump known as a synovial, or ________ \_\_\_\_\_\_ - infections of the synovial sheath can cause swelling in very specific and characteristic configurations that follow the shapes of these sheaths

Answer 46

ganglion cyst

Question 47

- a disease resulting the shortening, thickening, and fibrosis of the palmar aponeurosis and plamar fascia - results in partial flexion of the 4th and 5th digits

Answer 47

Dupuytren contracture