Wrist and ForearmLecture 15

The Wrist and Hand

the wrist and hand are used extensively in activities of daily living and in nearly all sports

The anatomy of the wrist is highly complex injuries to this region are often the result of

the natural tendency of the individual to sustain the force of the fall on the hyper-extended wrist

Often seen in ball handling sports

Bones and Articulations

the wrist and hand are composed of numerous small bones and articulations, which enable the dexterous movements performed by the hand and wrist both during sports and daily living

Distal radioulnar joint between the distal ulna and the radius allows for pronation and supination of the forearm triangular fibrocartilage (TFC) is the disc that makes

up a portion of the triangular fibrocartilage complex(TFCC) which acts as a stabilizer of the joint

often injured , can lead to serious problems

Radiocarpal joint is the major joint of the wrist condyloid shape where the radius articulates with

the scaphoid, lunate and triquetrum allows flex/ext, radial and ulnar deviations and circumduction

volar, dorsal , radial and ulnar collateral ligaments reinforce the radiocarpal joint

Carpometacarpel (CM) joint joint between the carpels and the

metacarpels gliding joint dorsal , volar and interosseous ligaments

l st CM (thumb) saddle joint

Metacarpalphalangeal ( MP) allows flex/ext , add/ abd condyloid joints reinforced by strong collateral ligaments

Interphalangeal (PIP, DIP) hinge joints flex/ext volar, and collateral ligaments

Muscle & Tendons of the Hand given the highly controlled and precise

movements that the hand and fingers can perform , there is no surprise that a large number of muscles are responsible

extrinsic muscles ( 9) , originate outside the wrist – cross wrist and insert in hand

intrinsic muscles (10) , originate in the hand or wrist, and insert in hand or wrist

Major Actions of the Wrist and Hand wrist – flex/ext/radial deviation/ulnar deviation/

circumduction thumb – flexion /extension/ adduction /abduction

and opposition fingers – flex/ext/add/abd/

Common Injuries to Wrist and Hand

Wrist Sprain result of a single trauma – or repeated

stress usually result of axial loading on the palm

during a fall on the outstretched arm severity depends on

i) magnitude of the force

ii) position of the hand on impact

iii) strength of tissue

point tenderness on dorsum of radiocarpal joint , pain increases with passive or active extension

because of the need to perform daily activity these injuries are often not given the time to heal and can lead to chronic instabilities

Rx – PIER, NSAIDS, modalities , immobilization , rule out fractures

Wrist Strains usually the result of an overload or over

stretching pain and restricted motion often occur with a wrist sprain difficult to distinguish if both are present Rx – PIER, NSAIDS, modalities ,

immobilization , rule out fractures

Triangular Fibrocartilage Complex

TFCC is located on the ulnar side of the wrist between the ulna and the triquetrum and pisiform

TFCC is a stabilizer of the distal radialulnar joint

Injuries are common but often missed diagnosed

Often caused by falling on outstretched hand , forced hyperextension of the wrist

s/s Pain and swelling on ulnar side of wrist Point tenderness ( TFCC) Decreased ROM and strength esp wrist

extension and ulnar deviation

Scaphoid #

most frequently fractured carpel ( 60 - 70%) usually the result of hyperextension during a

fall on the outstretched arm pain in anatomical snuff box , and pain with

wrist extension and radial deviation , possible loss of function

often misdiagnosed due to lack of evidence on xray – re xay in 2 weeks or bone scan

CAUTION - scaphoid has poor blood supply distal pole

Rx - PIER – refer to doctor immediately Casting involves a long process for

healing - minimum six weeks and maybe more if not healing properly

First Aid

Immediately apply ice with some type of splint that helps to immobilize the wrist

Elevate with use of a sling Refer for medical attention

Colles Fracture

fracture to the distal forearm involving one or both bones (usually the radius)

occurs with in 1 ½ inches of the wrist

results in a fork deformity (distal segment displaces in dorsal and radial direction)

First Aid

Immediately apply ice with some type of splint that helps to immobilize the wrist

Elevate with use of a sling Refer for medical attention Treat for shock

Skier’s or Gamekeeper’s Thumb thumb is exposed to

more force than fingers due to its position on the hand

integrity of the ulnar collateral ligament of the thumb is crucial for normal hand functions

UCL of thumb stabilizes the joint as the thumb is pushed against the index and middle fingers while performing pinching and grasping motions

usually occurs when MP joint is near full extension and thumb is forcibly abducted away from the hand

palmer aspect of the hand is swollen, bruising may be visible , point tenderness on UCL ( inside of the thumb) , instability and pain on stressing of the ligament

Rx – PIER , refer to doctor - severe cases may require surgical repair

Dislocations lunate is prone to dislocate during axial

loading dorsum of hand tender with a thickened

area distal to radius on the palm, swelling most common dislocation occurs at the

PIP or DIP joints, may be associated with open wounds

usually the result of hyperextension and axial compression , such as a ball hitting the end of a finger

obvious deformity ,pain , loss of function immediate treatment – reduction of finger

by trained individual Rx- PIER - xray – protection may take

awhile to heal

Carpal Tunnel Syndrome caused by direct trauma

or repetitive overuse condition is three times

more common in women , with right hand usually more common

this is due to the more repetitive tasks that women’s occupation usually involve (keyboard)

the carpel tunnel runs between the floor of the wrist and the transverse retinacular ligament that runs from the hamate and pisiform on the medial side to the trapezium and scaphoid on the lateral side

this tunnel accommodates the medial nerve, the flexors of the fingers and flexor pollicis longus

swelling of these tendons puts pressure on the median nerve

pain that wakes them at night , numbness, decreased grip strength

symptoms reproduced with pressure over the carpel tunnel

Rx - PIER - immobilization refer to doctor chronic conditions often end up with surgery

Mallet Finger

occurs when an object hits the end of a finger while the extensor tendon is taut

the resulting force avulses the lateral bands of the extensor mechanism from its distal attachment

obvious deformity , pain - check for fractures

Rx- PIER and immobilize joint in hyperextended position

Jersey Finger

This injury typically occurs when an individual grips an opponent’s jersey while the opponent is twists to get away

This ruptures the flexor digitorum profundus tendon from its attachment on the distal phalanx

Ring finger is the most commonly injured Individual will be unable to flex the DIP

joint Rx- PIER and refer to doctor , surgery

most likely will need to be performed

Boutonniere Deformity

caused by a blunt trauma to the dorsal aspect of the PIP joint

the central slip extensor tendon is ruptured at the middle phalanx, leaving the extensor mechanism intact over the PIP joint

this results in hyperextension at the MCP joint , flexion at the PIP joint and hyperextension at the DIP joint

Rx – PIER - needs to be referred to a doctor may need surgery

Ganglion Cysts

are begin tumour masses typically seen on the dorsal aspect of the wrist

associated with tissue sheath degeneration

contains fluid and is palpable between the extensors tendons

localised tenderness and some aggravation with wrist flexion

Rx – symptomatic – aspiration or injection , or surgical removal of the cyst

Ganglion Cysts

contains fluid and is palpable between the extensors tendons

localised tenderness and some aggravation with wrist flexion

Rx – symptomatic – aspiration or injection , or surgical removal of the cyst

Metacarpal Fractures

fractures usually result in sever pain, dorsal swelling and deformity

i) Bennets's # – articular fracture to the proximal end of the first metacarpal

usually occurs during axial compression as in when a punch is thrown with a closed fist

ii) Boxer's # - fracture of the 5th metacarpal

Rx – PIER – refer to doctor , may need closed or possibly open reduction depending on alignment

Subungual Hematoma

direct trauma to the nail bed capillaries burst from trauma and blood

gets trapped under the finger nail pressure builds and pain results soak for 10 to 15 minutes in ice water Rx - may need to drain the hematoma to

reduce the pressure