2 HANDThe hand is the region of the upper limb distal to the wrist joint.It is subdivided into three parts:1. Wrist2.Metacarpus3.Digits (five fingers including the thumb).The hand has an anterior surface (palm) and a dorsal surface (dorsum of hand).
3 Carpal tunnel and structures at the wrist The carpal tunnel is formed anteriorly at the wrist by a deep arch formed by the carpal bones and the flexor retinaculum.
4 Carpal archThe base of the carpal arch is formed medially by the pisiform and the hook of the hamate and laterally by the tubercles of the scaphoid and trapezium.
6 Flexor retinaculumflexor retinaculum is a thick connective tissue ligament that bridges the space between the medial and lateral sides of the base of the arch and converts the carpal arch into the carpal tunnel.
7 Structure and relations Four tendons of the flexor digitorum profundusFour tendons of the flexor digitorum superficialisOne tendon of the flexor pollicis longusMedian nerve
8 Carpal tunnel syndrome Carpal tunnel syndrome is an entrapment syndrome caused by pressure on the median nerve within the carpal tunnel.
9 Carpal Tunnel syndrome Common in computer professionals.Due to constant dorsiflexion of wrist while typing the keyboard
10 Palmar aponeurosisThe palmar aponeurosis is a triangular-shaped condensation of deep fascia that covers the palm and is anchored to the skin in distal regions.The apex of the triangle is continuous with the palmaris longus tendon.
11 Dupuytren Contracture of Palmar Fascia Dupuytren contracture is a disease of the palmar fascia resulting in progressive shortening, thickening, and fibrosis of the palmar fascia and aponeurosis.
12 Compartments of palm 1. Hypothenar compartment 2. Thenar compartment 3. Central compartment4. Adductor compartment5.Interosseous compartment
13 MusclesThe intrinsic muscles of the hand are located in five compartmentsAll of the intrinsic muscles of the hand are innervated by the deep branch of the ulnar nerve except for the three thenar and two lateral lumbrical muscles, which are innervated by the median nerve.
14 Muscles of the Hand Thenar Muscles Abductor Pollicis BrevisAbducts thumbOpponens PollicisTo oppose thumbFlexor Pollicis BrevisFlexes thumb
15 Muscles of the Hand Hypothenar Muscles Abductor Digit MinimiAbducts digit 5Flexor Digiti Minimi BrevisFlexes proximal phalanx of digit 5Opponens Digiti Minimibringing digit 5 into opposition with the thumb
20 Movements of thumbExtension: extensor pollicis longus, extensor pollicis brevisFlexion: flexor pollicis longus and flexor pollicis brevisAbduction: abductor pollicis longus and abductor pollicis brevis.Adduction: adductor pollicisOpposition: opponens pollicis.
21 Muscles of the Hand Short Muscles Lumbricals1 and 2Flex digits at metacarpo-phalangeal joints and extends interphalangeal joints3 and 4Dorsal interossei1-4Abducts digits from axial line and act with lumbricals to flex metacarpo-phalangeal joints and extends interphalangeal jointsPalmar interossei1-3Adducts toward axial line & assist lumbriaclas in flexing the same joints as above
23 Dorsal interossei Action of Dorsal Interossei : DAB : Abduction Little finger and thumb have no Dorsal interossei muscle
24 Palmar interossei Action of Palmar interossei : PAD :Adduction Middle finger and thumb have no palmar interossei muscle
25 Arteries of handBlood supply to the hand is by the radial and ulnar arteries, which form two interconnected vascular arches (superficial and deep) in the palm.
26 Ulnar artery and superficial palmar arch Ulnar artery+ palmar branch of radial artery
27 Radial artery and deep palmar arch Deep palmar arch: Deep palmar branch of ulnar artery+ radial artery
28 Allen's testTo test for adequate anastomoses between the radial and ulnar arteries, compress both the radial and ulnar arteries at the wrist, then release pressure from one or the other, and determine the filling pattern of the hand.
30 NervesThe hand is supplied by the ulnar, median, and radial nerves.
31 Ulnar nerveImmediately distal to the pisiform, ulnar nerve divides into a deep branch, which is mainly motor and a superficial branch, which is mainly sensory.Deep branch: supplies the hypothenar interossei, adductor pollicis, and the two medial lumbricals.Superficial branch: supply skin on the palmar surface of the little finger and the medial half of the ring finger
33 Ulnar nerve injuryThe ulnar nerve is most commonly injured at two sites:1. Elbow2. wristClawing of the hand:Metacarpophalangeal joints of the fingers are hyperextended and the interphalangeal joints are flexed.
35 Ulnar Canal Syndrome (Guyon Tunnel Syndrome) Compression of the ulnar nerve may occur at the wrist where it passes between the pisiform and the hook of the hamate.
36 Median nerveThe median nerve is the most important sensory nerve in the hand because it innervates skin on the thumb, index and middle fingers, and lateral side of the ring finger.Branches:1. Recurrent branch: innervates the three thenar muscles2. Palmar digital nerves: In addition to skin, the digital nerves supply the lateral two lumbrical muscles
38 Ape handRefers to a deformity in which thumb movements are limited to flexion and extension of the thumb in the plane of the palm.Severance of median nerve paralyzes the thenar muscles and the thumb loses much of its usefulness.
39 Superficial branch of the radial nerve The only part of the radial nerve that enters the hand is the superficial branch.Innervates skin over the dorsolateral aspect of the palm and the dorsal aspects of the lateral three and one-half digits distally to approximately the terminal interphalangeal joints.
41 A 21 year old girl is brought to the emergency department with a puncture wound on the palmar side of her left index finger. Preservation of which of the following movements of her index finger will confirm the functional integrity of the flexor digitorum profundus muscle? Flexion of the metacarpophalangeal jointAdductionAbductionFlexion of the distal interphalangeal jointFlexion of the proximal interphalangeal joint
42 .A 53-year-old African American man involved in a motor vehicle accident sustains a severe mid-shaft fracture of the right humerus. Vitals are Temp-100.0F, BP-120/88mm/Hg, pulse- 118/min, and RR- 14/min. Examination reveals wrist drop and no ulnar or radial pulses in the right arm. Examination reveals decreased sensation over the dorsal aspect of the lateral 3½ digits. The rest of the physical exam is otherwise unremarkable. What nerve is most likely injured given the findings in this patient?A.Axillary nerveB.Musculocutaneous nerveC.Median nerveD.Radial nerveE.Ulnar nerve
43 3The figure below represents cutaneous innervation of wrist and hand. The area A in the figure represents which Nerve?Superficial branch of radial nerveAnterior interosseous nervePalmar branch of median nervePalmar branch of ulnar nerveLateral cutaneous nerve of fore arm