PT3 - The Wrist And Hand Flashcards
1
Q
What is the function of the wrist?
A
- wrist serves hand function
- maladaption may be transmitted to write via rotary radial system
- maladaption may be due to OA @ elbow + misalignment of radius/ulna from fracture/tears of triangular fibro-cartilage
- fracture may result in normal anatomy, but function may be affected => suggesting soft-tissue injury
- soft tissue + triangular fibrocartilage disruption may compromise wrist biomechanical system
- distal radio-ulna joint => extensive forearm rotation
- radio-carpal joint provides function for hand in various rotational positions
- large torque delivered to stabilised radio-carpal complex without interfering in flexion/extension or radio/ulna deviation
- large range of motion of forearm and writs without interfering with grasping of hand
2
Q
What makes up for the fact that the ulna is shorter than the radius?
A
- triangular fibrocartilage disc (TFC) => joint surface is more congruent
3
Q
Describe the radiocarpal joint
A
- biaxial ellipsoid joint
- active movements = flexion, extension, adduction, abduction, Circumduction
4
Q
How can the triangular fibrocartilageous disc be compromised?
A
- under compression + torque
- carpals maintain a stable structure
5
Q
Describe the radiocarpal joint
A
- compound sine wave (sinusoidal) joint
- axis of movement controlled by shape of articular surfaces + strong radiate-carpitate ligament
6
Q
What ligaments control the radiocarpal joint?
A
- radiate-capitate
- dorsal
- palmar
- medial collateral
- lateral collateral
7
Q
Describe the inter-carpal joints
A
- non-axial joints
- glide in response to muscles/tendons/fascia acting on them
- dorsal ligament (back of hand) stronger than palmar
- dorsal ligaments reinforced by interosseous ligaments
- carpal bone subluxation => common => fall on dorsi flexed hand
- all carpal bones dislocate dorsally, except lunate
- lunate dislocates in a palmar direction => swelling on palmar side of wrist + limited finger flexion + median nerve compression/carpal tunnel syndrome
8
Q
What is tenosynovitis?
A
- excessive repetitive movement or un-physiological stress on tendon => inflamed sheaths + impaired + painful movement
- pain is felt on any movement involving the tendon
- tendons are swollen + crepitation may be elicited in motion
- normally affects extensor carpi ulnaris, abductor policis longus + extensor pollicis brevis (quevain’s)
9
Q
Consider the tissues in the wrist and hand that could become symptomatic with the following activities:
- typing on a keyboard in an office environment
A
- repetitive movement through a small area of the body => body isn’t good at producing force just through the same movement over and over again
- if hand is lifted into extension => carpal tunnel syndrome as the carpal tunnel becomes compressed, especially as extensors are stronger than flexors of the writs
- tendon sheath around extensor pollicis brevis + abductor pollicis longus may narrow as aging + excessive use occurs and use of thumb for typing => tenosynovitis
- changes in elbow e.g. fracture or OA may impact wrist function as misalignment may result in tears of triangular disc
10
Q
Consider the tissues in the wrist and hand that could become symptomatic with the following activities:
- falling onto an outstretched hand (FOOSH)
A
- might result in the lunate being pushed towards palm => restriction in flexion movements + carpal tunnel + median nerve compression
- and capitate pushed dorsally => swelling, radiating pain on dorsal side of hand
- triangular fibocartilage may also be compressed under the pressure of the fall + potentially torque as hip come down towards ground
11
Q
Consider the tissues in the wrist and hand that could become symptomatic with the following activities:
- hairdressing in a successful salon with too few wrist breaks
A
- lots of torque movements on the wrist required during hair dressing => torque + compression as using heavy equipment e.g. hairdryer for Prolongued periods of time => fibrocartilagenous disc compression
- extension movements as cutting hair => carpal tunnel narrowing + median nerve compression
- quevain’s due to thumb extension in scissors => extensor pollicis brevis + abductor pollicis longus
- may also get symptoms on ulna side as extensor carpi ulnaris lifts to move out of the way of closing scissors
12
Q
Consider the tissues in the wrist and hand that could become symptomatic with the following activities:
- cycling
A
- high compression through wrist being in extension, more laterally => carpal tunnel syndrome + median nerve compression
- FOOSH injury if falling off bike => lunate coming towards palmar side => pain + swelling + limited finger flexion and capitate/other carpals coming dorsally if hand is dorsi flexed
13
Q
What is a common fracture site in the wrist?
A
- radius due to FOOSH (fall on out stretched hand)
14
Q
How can you normally detect a broken radius?
A
- deformed (hanging) hand
- won’t be able to use hand (or cracking evident)
- very sore + bruised + swollen
- loss of function due to swelling
- brushing generalised where contacted ground
- significant + quickly
- won’t be be able to pronate hand (function of radius)
- won’t be able to weight bear on hand
15
Q
If you have a radius fracture, which movement will be impaired?
A
- pronation (the function of the radius)
