Bones divided into structural and functional divisions
Muscles controlling can be found extrinsically and intrinsically
Foot adapted for weight bearing, hand adapted for prehension
Joints of the Hand - Carpometacarpal & Intermetacarpal Joints
Carpometacarpal and intermetacarpal joints are a series of synovial plane joints (except 1st)
Articular surfaces are covered in hyaline cartilage and surrounded by a capsule and synovial membrane - reinforced by palmar, dorsal and interosseous ligaments
Functionally important to allow gliding during hand and wrist movements
1st Carpometacarpal Joint
Syonivial saddle joint (typical synovial joint)
Reinforced by radial collateral (trapezium to MC),anterior oblique (covers joint obliquely anteriorly) and posterior oblique (covers posterior joint obliquely) ligaments
Functionally oblique ligaments produce a conjunct rotation of the MCP joint
Metacarpophalangeal (MCP) Joints
Synovial condyloid joints between rounded head of metacarpals and concave bases of proximal phalanges
Typical synovial joints - note extended area for articulation on the anterior aspect of metacarpal heads
Ligaments pass from lateral tubercles to palmar aspect of proximal phalanx - taut in flexion and therefore limit abd/adduction in this position
Note also volar (plate) and transverse ligaments
Interphalangeal (IP) Joints
Proximal (PIP) and distal (DIP) joints - uniaxial synovial hinge joints
Between distal rounded ends of phalanges with proximal concave ends of adjacent phalanx
Typical synovial joints reinforced by strong collateral ligaments
Intrinsic muscles of the hand
Muscles which have proximal and distal attachments within the anatomical boundaries of the hand
Anatomically distinct areas
Thenar eminence
Hypothenar eminence
Interossei/lumbricals
Thenar Eminence
Include
Superficial
Flexor pollicis brevis
Abductor pollicis brevis
Deep
Adductor pollicis - 2 heads (transverse and oblique)
Opponens pollicis
NS: Median nerve except adductor pollicis that is supplied by the ulnar nerve (C8,T1)
Hypothenar Eminence
Also divided into deep and superficial muscles
Superficial
Flexor digiti minimi
Abductor digiti minimi
Deep
Opponens digiti minimi
NS: Ulnar nerve C8,T1
Palmar Interossei
Between adjacent metacarpals - unipennate
Attach to the bases of proximal phalanges (medial 2 to 4th 5th digits, lateral 1 to 2nd digit)
Adductors of the MCP joints of index, ring and little fingers
NS: Ulnar nerve C8,T1
Dorsal Interossei
Bipennate - from adjacent metacarpals
To bases of proximal phalanges - 1st and 2nd to lateral side of index and middle, 3rd and 4th to medial side of middle and ring fingers
Abduction of MCP of index, middle and ring fingers
NS: Ulnar nerve C8,T1
Lumbricals
4 muscle attaching the long flexor tendons (FDP) with the dorsal digital expansion of ED - 1st pair unipennate and 2nd pair bipennate
A: flexion of MCP and extension of IP joints
NS: medial pair via ulnar nerve, lateral pair via median nerve (C8,T1)
