The bones of the hand Capitate by 2

The bones of the hand

Capitate – by 2 nd month Hamate by 3 rd month Ossification of carpal bones Triquetral by 3 rd year Lunate by the 4 th year Scaphoid, Trapezium and Trapezoid by 5 th year Pisiform 10 to 12 th year Females ossify before males.

The joints of the hand

The wrist joint

Joints of the wrist area Wrist joint Joints between proximal row of carpal bones Joints between distal row of carpal bones Joints between the proximal and distal rows

Movements of wrist Flexion 85 deg. Mostly at radiocarpal joint Extension 85 deg. Mostly midcarpal Abduction 15 deg. Mostly midcarpal Adduction 45 deg. Mostly radiocarpal

Carpometacarpal joints The thumb: Between first metacarpal base and the trapezium Sellar type joint Wide mobility Palmar, dorsal ligaments and Lateral ligament Second to fifth carpometacarpal joints and intermetacarpal joints have restricted mobility

Metacarpo-phalangeal joints Ellipsoid joints (sometimes called bicondylar) Palmar and collateral ligaments for stability Fair range of movements Flexion 90 deg or more but extension small Abduction and adduction limited more so in flexion.

Inter phalangeal joints

The carpal tunnel

Other tunnels & canals

is a space at the wrist between flexor retinaculum and the palmar carpal ligament (which runs between the pisiform bone and the hamate bone), through which the ulnar artery and the ulnar nerve travel into the hand.

Near the elbow – the ulnar nerve is pinched

The muscles of the hand aka Small muscles of hand aka Intrinsic muscles of hand

The fascia of the hand

Fascial framework/skeleton Aponeuroses Sheaths Retiancula Bands Septa

Fascial spaces

Longitudinal fibre system Palmar aponeurosis These are in three layers Just under skin Deep to web space apex and fingers A third layer on either side of the MPJ and attach to metacarpal, proximal phalanx and extensor tendon

Palmar fascial complex Transverse fibre system Vertical fibre system

Transverse system Flexor retinaculum It is attached, medially, to the pisiform and the hamulus of the hamate bone; laterally, to the tubercle of the scaphoid, and to the medial part of the volar surface and the ridge of the trapezium.

Flexor tendon sheaths Annular Criciate Pulleys

Extensor or Dorsal

Synovial sheaths and spaces

Altered balance in tendon and tissue tensions result in deformity

Mallet finger

Infected, swollen finger.

The skin of the hand

Skin of the hand Dorsal skin Palmar skin Relationship to the fascial framework Fat pads

Wrist and palmar creases Wrist has three lines Proximal at the level of flexor synovial sheaths Intermediate at the level of wrist joint Distal at the level of flexor retinaculum These creases fix and bend - “skin joints”