Presentation on theme: "Bones, Joints, and Muscles of the Forearm, Wrist, and Hand"— Presentation transcript:
1 Bones, Joints, and Muscles of the Forearm, Wrist, and Hand
2 TerminologyThe wrist/hand region consists of 29 bones and multiple joints - which lends to high mobility.Wrist:As a joint, it is the articulation between the forearm and hand.Sometimes, the wrist is discussed as a region, which would include the carpal bones.HandThe bones distal to the wrist joint.As a region, the wrist is part of the hand.
3 Bones 29 bones including: (2 from the forearm, 27 from the hand) Distal aspect of the radius and ulna8 carpal (bulk of the hand)14 phalanges (the fingers)5 metacarpalsTotal: =29
4 BonesRadius and UlnaThe radius is more massive distally than the ulnaThe ulna is more massive proximally than the radiusRemember, forearm pronation and supination are the result of the radius rotating about the ulna
12 Forearm Pronators and Supinators Biceps BrachiiSupinatorBrachioradialisPronators:Pronator TeresPronator QuadratusBrachioradialis
13 Pronator Teres O: Medial Epicondyle of Humerus I: Medial and Lateral Surface of RadiusA: Pronation of Radioulnar JointIntegrated Function: Assists in deceleration of supination of radioulnar jointAssists in dynamic stabilization of radioulnar joint
14 Pronator Quadratus O: Distal anterior ulna I: Distal anterior radius A: Forearm PronationIntegrated Function: Assists in deceleration of supination of radioulnar joint
15 Supinator O: Lateral Epicondyle of Humerus I: Wraps around proximal radiusA: Supination of Radioulnar JointIntegrated Function: Assists in deceleration of pronation of radioulnar jointAssists in dynamic stabilization of radioulnar joint
19 Attachments Wrist Flexors All originate from the medial epicondyle of the humerusInsertions: anterior aspect of the wrist and handWrist ExtensorsAll originate from the lateral epicondyle of the humerusInsertions: posterior aspect of wrist and hand
20 Attachments Wrist Abductors Wrist Adductors Origin: anterior or posterior aspect of forearmInsertion: radial side of handWrist AdductorsInsertion: ulnar side of hand
21 Flexor Carpi Radialis O: Medial Epicondyle of Humerus I: Bases of 2nd and 3rd metacarpalsA: Flexion and Abduction of wrist (radial deviation)
22 Flexor Carpi Ulnaris O:Medial Epicondyle of Humerus I: Pisiform A: Flexion and Adduction of Wrist (ulnar deviation)
23 Palmaris Longus Absent in 15 - 20% of Population O: Medial Epicondyle of HumerusI: Palmar AponeurosisA: Wrist flexionQ: How do you test for this muscle and why is it important?
24 Palmaris Longus Tested: With wrist slightly flexed Oppose thumb and little fingerImportance:Used in tendon transfers (autografts)
25 Flexor Digitorum Superficialis O: Medial Epicondyle of HumerusI: 2nd through 5th PhalangesA: Finger Flexion and Wrist Flexion
26 Integrated Function of Wrist Flexors Assists in deceleration of wrist extensorsAssists in dynamic stabilization of the wrist and handFlexor Carpi Radialis and Flexor Carpi Ulnaris:Assists in deceleration of wrist abdutionFlexor Digitorum Superficialis:Assists in deceleration of finger extension
27 Extensor Carpi Radialis Brevis O: Lateral Epicondyle of HumerusI: Base of 3rd metacarpal on dorsal surfaceA: Extension of wristAbduction of Wrist
28 Extensor Carpi Radialis Longus O: Lateral Epicondyle of HumerusI: Base of 2nd metacarpalA: Extension of wristAbduction of wrist(radial deviation)
29 Extensor Carpi Ulnaris O: Lateral Epicondyle of HumerusI: Base of 5th metacarpal on dorsal surfaceA: Extension of WristAdduction of Wrist (ulnar deviation)
30 Integrated Function of Wrist Extensors Assists in deceleration of wrist flexionAssists in dynamic stabilization of the wrist and handExtensor Carpi Radialis Brevis and Longus:Assists in deceleration of wrist adductionExtensor Carpi Ulnaris:Assists in deceleration of wrist abduction
31 Nerves Three primary nerves of the wrist and hand: Radial Nerve Innervates the triceps brachii and provides sensation to dorsal side of thumb, index, middle, and half of ring fingerUlnar NervePalmar side of the little finger and half of the ring fingerMedian NervePalmar side of thumb, index , and half of ring finger
33 Common Medical Conditions Fractures, strains, sprains, dislocationsScaphoid bone is most frequently fractured carpal bone“Hook” of the Hamate fracture
34 Common Medical Conditions Boutonniere Deformity and Mallet FingerCaused by the rupture of the extensor tendonAny extensor tendon
35 Carpal Tunnel Syndrome A disorder that causes numbness in the hand and pain in the wrist due to the compression of the median nerve
36 Carpal Tunnel Syndrome Etiology:Short, repetitive movement, such as typing, knitting, and using vibrating tools for hours on endThe lack of rest in between these motions irritates and inflames the flexor tendons that travel with the median nerve to the hand through an area in the wrist called the "carpal tunnel," which is surrounded by bones and a transverse ligament.The inflamed tendons squeeze the nerve against the ligament.
37 Carpal Tunnel Syndrome The symptoms Include:Pain, numbness, or tingling in your hand and wrist, especially in the thumb and index and middle fingers; pain may radiate up into the forearmIncreased pain with increased use of your hand, such as when you are driving or reading the newspaperIncreased pain at nightWeak grip and tendency to drop objects held in the handSensitivity to coldMuscle deterioration especially in the thumb (in later stages).Treatment:Diagnosis by physicianOccupational Therapy/Physical Therapy
38 Prevention of Carpal Tunnel Syndrome Ergonomics:Proper seatingThe height of your seat and the position of your backrest should be adjustableThe chair should be on wheels so you can move it easilyIf you can adjust your table, set your waist angle at 90 degrees, then adjust your table so that your elbow makes a 90 degree angle when your hands are on the keyboard
39 Prevention of Carpal Tunnel Syndrome Ergonomics:Elbow angle at 90 degrees. Try to hold your elbows close to your sides to help minimize "ulnar displacement" the sideways bending of the wrist (as when reaching for the "Z" key)Waist angle at 90 degreesWith your elbows and waist at 90 degree angles, your feet should rest comfortably flat on the floor.
41 Carpal Tunnel Syndrome Exercises Stretch the following muscles:Elbow FlexorsWrist FlexorsFinger FlexorsThis will reduce the compression of the median nerve within the carpal tunnelEXTENSION EXERCISES ARE THE KEY TO RECOVERYStrengthen the following muscles:Elbow ExtensorsWrist ExtensorsFinger ExtensorsFinger AbductorsThis will help hold the carpal tunnel open