Clinical Anatomy Of The Wrist And Hand Flashcards
Explain in detail, the basics of the wrist joint
Synovial joint between the distal end of the radius and ulna with the carpal bones
- Radius articulate with scaphoid and lunate - Radioulnar disc articulates with the lunate and triquetrum
Intercarpal joints
- synovial joints shared a single capsule
- limited movements but contributes to the positioning of the hand in flexion, extension, abduction and flexion
What is the function of the wrist joint?
Allows movement of the hand around two axes
-flexion and extension
-Abduction (lateral deviation) and adduction (medial deviation)
What are the bones of the wrist?
Proximal row- lateral to medial
- Scaphoid
- Lunate
- Triquetrum
- Pisiform(pea shaped)
Distal row- lateral to medial
- Trapezium
- Trapezoid
- Capitat: articulate with the base metacarpal III
- Hamate- hook on Palmer surface
Summarize joints and bones of the hand
1st carpometacarpal(CMC) joint between trapezium and base of thumb -saddle joint which permits flexion, extension, abduction, adduction, and opposition of the thumb
2nd to 5th carpomatcarpal (CMC) joints only permits limited gliding movements
Metacarpopharyngeal (MCP)- joints permits flexion, extension, abduction and adduction of digits
Interpharyngeal(IP) joints permits flexion and extension
What is the anatomical snuff box?
A triangular depression formed on the poster lateral side of the wrist
What are the borders and contents of the anatomical snuff box?
Lateral border
- abductor pollicus longus
- extensor pollicis brevis
Medial border:
-extensor pollicis longus
Roof:
- Superficial branch of the radial nerve
- cephalic vein
Floor:
- Scaphoid and trapezium
- distal ends of the tendons of ECRL & ECRB
Contents: radial artery
What are the clinical consequences of delaying treatment if anatomical snuff box falling on his outstretched hand?
Nonunion, avascular necrosis of proximal portion
Explain boxers fracture
Impaction fracture of the neck fifth metacarpal (sometimes can involve fourth metacarpal )
- Usually commipunicated
- Usually because of a direct blow with a clenched fist against a solid surface
What is Colle’s fracture?
Fracture of the distal radius with posterior displacement of the distal
Dinner fork deformity
What is Smith’s fracture?
Garden spade deformity
Fracture of the distal radius with anterior displacement of the distal fragment
What is the scaphoid fracture?
Usually around the Neck. MaY lead to avascular necrosid of the proximal fragment
What is carpal tunnel ?
The carpal tunnel is formed anteriorly at the wrist
Floor: deep arch formed by the carpal bones
Roof: flexor retinaculum
Contents: the tendons of FDS, FDP FPL, & the median nerve
Describe Guyon’s Canal
Roof: palmar canal ligament
Floor: flexor retinaculum and hypothenar muscles
Contents: ulnar nerve artery and vein
What are the compartments of the hand?
Midpalmar (central)- contains long flexor tendons, lumbricals, palmar arches
Thenar eminence- contains FPL tendon and three thumb muscles. Recurrent median nerve
Hypothenar eminence- Contains three little finger muscles and deep motor branch of the ulnar nerve
Four interosseous spaces- palmar and dorsal interosseous muscles. Deep motor division of the ulnar nerve
Explain Dupuytren’s Contracture
- Flexion contracture of the hand
- Thickening and contraction of the palmar aponeurosis
- nodule formation
- unable to extend fingers
How can Dupuytren’s contracture be treated?
- Needle aponeurotomy is a minimally invasive technique where the cords are weakened through the insertion and manipulation of a small needle. Once weakened, the offending cords may be snapped by simply pulling the finger(s) straight
- Surgical- cutting out thickened and contracted bands in palmar aponeurosis
What are the tendon sheaths of the hand?
- Fibrous digital tendon sheaths
- Synovial sheaths
- Radial bursa
- Ulnar bursa
Clinical correlate: trigger finger (stenosing tnsynovitis)
What are the fibrous digital tendon sheaths ?
Dense connective tissue surrounding tendons of FDP, FDS, & FPL muscles
Hold tendons to the phalanges and prevent bowing
What are the synovial sheaths of the hands?
Within the fibrous sheath the tendon has a synovial sheath directly surrounding it
What is the radial bursa?
Synovial sheath surrounding the tendon of FPL continuing through to carpal tunnel
What is th Ulnar bursa
Common flexor sheath
Synovial sheath surrounding the tendons of FDP &. FDS of 5th digit continuing through the midpalmar space and into the carpal tunnel
What is trigger finger(stenosing tenosynovitis)?
- fibrosis and tightening of the fibrous digital sheath of the flexor tendons at the level of the metacarpophalangeal (MCP) joint
- Inflammation and nodule formation of the flexor tendons
-Triggering of the affected finger is due to tendons requiring excessive force to fully extend or flex
(Clinical correlate: inflammation of synovial sheaths)
What are extensor sheaths
Tendons of extensor digitorum and extensor pollicus longus expand over the proximal phalanx, makes a “hood” which then divides into a central band and 2 lateral bands
Serves as an attachment for:
- lumbricals
- dorsal interossei
- palmar interossei
- due to attachment, these muscles also extend at the interphalangeal joint
List the intrinsic muscles of the hand
Hypothenar group-deep branch of the ulnar nerve
1. Flexor digiti minimi
- Abductor digiti minimi
- Opponents digiti minimi
Lumbricals
Thenar group: recurrent branch of the median nerve
1. Flexor pollicis brevis
- Abductor pollicis brevis
Oppnens pollicis
What are the functions of the dorsal interosseous ?
Abduction of digits
Extension of digits
Deep branch of the ulnar nerve
One part inserts inti dorsal hood, another part inserts into base of proximal pharynx
What is the function of the palmar interosseous?
Adduction
Extension of digits
Deep branch of the ulnar nerve
Inserts into dorsal expansion
What is the function of the adductor pollicis?
- Adducts the thumb
- deep branch of the ulnar nerve
What is the blood supply of the superficial palmar arch?
Mainly from ulnar artery
What is the blood supply of the deep palmar arch?
Mainly from radial artery
Come back fir clinical correlate- Allen test
Briefly describe veinous drainage of the hand
Superficial veins:
-On the dorsum of the hand, the dorsal venous network coalesces on the medial side of the wrist to form the basilic vein and on the lateral side of the wrist to form the cephalic vein
Deep vein:
Superficial and deep venous palmar arches accompany arterial Palmer arches in the hand
Drain into the paired radial and ulnar veins
Summarize general lymphatic drainage of the upper limb
Can be divided into deep & superficial
Follows the same path of veinous drainage of the upper limb
All lymphatics drain to the axillary nodes
Superficial drainages veins within the skin and superficial fascia
- medial hand, forearm and arm
- Lymphatic fluid will go to lateral (humeral) axillary nodes then to central axillary nodes, then finally to Apical axillary nodes
Lateral hand, forearm and arm
-lymphatic fluid will go directly to the Apical axillary nodes
All lymph then pass from Apical to Subclavian trunk to lymphatic /thoracic duct
Discuss deep drainage of the upper limb
Deep drainage: veins within the compartments
-Lymohatic fluid from the compartments of hand, forearm, and arm will go to lateral (humeral) nodes, then to central then finally to Apical
All lymph then pass from Apical to Subclavian trunk to lymphatic/thoracic duct
