Lecture 6.3 Flashcards
What bones interact at the radiocarpal joint?
Proximal row and the radius make contact at the scaphoid + lunate + triquietrum and the styloid process..
What is the midcarpal joint?
Midcarpal joint is a functional joint between proximal and distal row.
What are intercarpal joints?
Intercarpal joints is between capral bones
What kind of joint is the wrist joint?
A condyloid joint. (reciprocal concave/conves joint)
What are the motions associated with the hand in the coronal plane?
Ulnar and radial deviation at the radiocarpal joint.
What are the ligaments of the wrist joint?
Medial and lateral collateral ligaments
Palmar and dorsal radiocarpal ligaments
palmar and dorsal radioulnar ligaments
Why is ulnar deviation more prominent than radial deviation?
At distal radioulnar joint radius projects more distally and has a concavity that causes ulnar deviation
How are the carpal bones held against the radius during ulnar deviation movements?
Sling like ligaments hold the carpal bones against the radius
What joint is the triangular disk distal to the ulnar a part of?
Triangular disk is also part of the distal radioulnar joint.
What is the blood supply for the wrist joints?
Branches of the palmar and dorsal palmar arches.
What is the anterior interosseus nerve a branch of?
median nerve
What is the posterior interosseus nerve a branch of?
Radial nerve
What nerves supply the carpal bones?
Anterior interosseus nerve
Posterior interosseus nerve
Deep branch of ulnar nerve
What are the ligaments of the intercarpal joints?
Interosseus ligaments
Anterior ligaments
Posterior ligaments
(palmar and dorsal arches = blood supply, interosseus arches with deep branch of the ulnar nerve = nerve supply)
What kind of orientation does the articular capsule have around the carpal bones?
One big joint capsule covers all carpal bones.
How often are carpal bones fractured?
Carpal bones rarely fractured (except for scaphoid fracture)
What type of joint is the midcarpal joint? What is the shape of the joint?
midcarpal joint is a condyloid joint and is a concave convex joint.
What has a greater deviation at the midcarpal joint?
Radial deviation
What are the non-wrist joints of the hand?
Carpometacarpal (CMC)
Intermetacarpal (IMC;laterally)
Metacarpophalangeal (MCP)
Interphalangeal (IP)
What type of joints are all carpometacarpal and intermetacarpal joints?
Synovial
What type of joint can be found between trapezium and first metacarpal?
Synovial, Saddle joint
Relative to what finger do actions of the hand happen? What can be said about its mobility?
Actions in the hand happen relative to the middle finger. This bone is immobile as well as second metacarpal..
What kind of movements can happen at IMC joints?
gliding movements
What ligaments stabilize the CMC and IMC joints?
CMC, IMC
Interosseus ligaments
Collateral ligaments (CMC)
What ligaments stabilize the MCP and IP joints?
Collateral ligaments
Palmar (Volar) plate
Dorsal plate
What type of joints are MCP joints?
Condyloid joints
What type of joints are IP joints?
hinge joints
How are the medial 4 fingers held together?
Metacarpals are connected by the deep transverse metacarpal ligament to hold the medial 4 fingers together.
What is the function of the volar plates?
Volar plates hold the tendons within the fingers.
Where are volar plates found?
At the MCP and IP joints
How do volar plates create modified hinge joints at the fingers?
Volar plates give more surface area for lumbrical attachment to allow some rotation at the MCP and IP joints creating a modified hinge joint
What is skier’s thumb?
Skier’s thumb occurs when the thumb is forced into extension and abduction causing rupture of medial collateral ligament.
What is a possible problem associated with skier’s thumb?
Adductor pollicis longus tendon can get pinched in the joint of the thumb.
What results from damaged palmar volar plates?
Swan neck deformity results due to tendon drifting off to the side causing hyperextension. And as a result the distal phallanx is flexed.
What results from dorsal volar plate rupture?
Dorsal volar plate rupture causes boutonniere deformity.
What can occur from a ruptured extensor expansion in the finger?
extensor expansion rupture causes ‘mallet’ finger resulting in flexion of distal IP joint.
What does the common flexor sheath enclose?
Common flexor sheath encloses FDS and FDP tendons.
What bursa does FDL go through?
FPL goes through radial bursa
What structures in the palmar aspect of the hand are not enclosed in synovial sheaths?
The lumbricals
What is the function of the digital synovial sheaths?
Digital synovial sheaths enclose tendons and encover tendons in synovial fluid making movements smoother and providing nutrition to the tendons.
What is the function of the fibrous covering of the digital synovial sheaths?
fibrous covering holds the digital synovial sheaths in place
What are the fibres that hold the sheaths in place?
Annular fibres
Cruciform fibers
Where are the volar plates found relative to the fibrous flexor sheaths?
Deep to the fibrous flexor sheaths is the volar plates and the bones.
What is the clinical significance of the communication between the pinkie’s digital sheath and the ulnar bursa?
Spread of infection from the pinkie to the ulnar bursa and vice versa
What structures can get inflamed in the fingers?
Tendons, synovial sheaths, and fibrous sheaths.
What causes tenovaginitis?
The fibrous sheath covering the synovial sheaths can get inflamed and this is known as tenovaginitis.
What is Tinel’s test?
Skin is pinched at ulnar and radial side to see which nerve is damaged.
What causes hand of benediction?
injury or compression at proximal part of the median nerve.
