Anatomy of the human midcarpal joint - information:
Midcarpal articulation, art. mediocarpea, located between the first and second rows of carpal bones, minus the pisiform bone, which is a sesamoid. The glenoid cavity of this joint is the distal surface of the first row of carpal bones. The proximal surface of the second row of the wrist forms the articular head. Both wrist joints (radiocarpal and midcarpal) have independent articular capsules attached to the edges of their articular surfaces.
The capsule of the wrist joint is strengthened by auxiliary ligaments on the radial and ulnar sides: lig. collaterale carpi radiate, going from the styloid process of the radius to the scaphoid bone, and lig. collaterale carpi ulnare, extending from the styloid process of the ulna to the os triquetrum and os pisiforme. On the palmar side of the wrist joint there is a lig. radiocarpeum palmare, which, starting widely from the styloid process and from the edge of the articular surface of the radius, is attached to the os scaphoideum, lunatum, triquetrum et capitatum by several bundles. On the dorsal side, the capsule of the wrist joint is reinforced by the lig. radiocarpeum dorsale, which goes from the radius to the bones of the first row of carpal bones.
At the point of attachment of the ligaments of the wrist joint to the bones, the latter include blood vessels and nerves, damage to which during operations entails pathological changes in the bones. Capsule art. mediocarpea also includes the last four carpometacarpal joints, which communicate with each other.
Besides art. mediocarpea, individual carpal bones connected to each other by interosseous ligaments, ligg. intercarpea interossea, in places articulate with each other with articular surfaces facing each other. Such joints are called intercarpal joints, articulationes intercarpeae. The intercarpal joints are reinforced by a number of short ligaments, running mostly transversely from one bone to another on the dorsum, ligg. intercarpea dorsalia, and palmar, ligg. intercarpea palmaria, sides. On the palmar side, in addition, there are bundles diverging from the capitate bone to the neighboring bones, lig. carpi radiatum.
Movements in the wrist joints occur around two mutually perpendicular axes passing through the head of the capitate bone, around the frontal (flexion and extension) and around the sagittal (abduction and adduction). These movements are inhibited by ligaments that are located perpendicular to the axes of rotation and at their ends, namely: collateral - at the ends of the frontal axis, dorsal and palmar - at the ends of the sagittal axis. Therefore, the former inhibit abduction and adduction around the sagittal axis, and the latter inhibit flexion and extension around the frontal axis. As in all biaxial joints, circumductio is also possible here, in which the ends of the fingers describe a circle.
Joints of the hand
The wrist joint (articulatio radiocarpea) is complex (Fig. 1). The shape of the articular surfaces is elliptical. It is formed by the articular surface of the radius, the articular disc and the proximal row of carpal bones (scaphoid, lunate, triquetrum). An articular disc separates the distal radioulnar joint from the radiocarpal joint. Movements around the frontal axis - flexion and extension, and around the sagittal axis - abduction and adduction are possible.
The wrist joints, intercarpal joints (articulationes intercarpales), connect the bones of the wrist. These joints are strengthened by interosseous and intercarpal ligaments (ligg. interossea et intercarpea), palmar and dorsal intercarpal ligaments (ligg. intercarpea palmaria et dorsalia).
The pisiform joint (articulatio ossis pisiformis) is the joint between the pisiform bone, located in the extensor carpi ulnaris tendon, and the triquetrum bone.
Carpometacarpal joints (articulationes carpometacarpals) are complex. They articulate the second row of carpal bones with the bases of the metacarpal bones. II-IV carpometacarpal joints belong to flat joints. They are strengthened by palmar and dorsal ligaments.
The carpometacarpal joint of the thumb (articulatio carpometacarpea pollicis) is formed by the trapezium bone and the base of the first metacarpal bone; This is the saddle joint. Movements in the joint are carried out around two axes: frontal - opposition (opposition) and reverse movement (reposition) and sagittal - abduction and adduction.
Intermetacarpal joints (articulationes intermetacarpals) are located between the bases of the II-V metacarpal bones.
Metacarpophalangeal joints (articulationes metacarpophalangeae) are formed by the heads of the metacarpal bones and the fossae of the bases of the proximal
phalanges of fingers. The metacarpophalangeal joints of the II-V fingers have a spherical shape. The joints are strengthened by ligaments. Movements in them are possible around the frontal axis - flexion and extension, the sagittal axis - abduction and adduction; Rotational movements are also possible, and in the first metacarpophalangeal joint - only flexion and extension.
The interphalangeal joints of the hand (articulationes interphalangeae manus) are formed by the heads and bases of the middle phalanges, the heads of the middle and the bases of the distal phalanges. These are block-shaped joints in shape. Ligaments run along the lateral surfaces of the joint. Movements in the joint are possible around the frontal axis - flexion and extension.
Rice. 1. Joints and ligaments of the hand: a - front view: 1 - distal radioulnar joint; 2 - ulnar collateral ligament of the wrist; 3 - pisiform-uncinate ligament; 4 - pisiform-metacarpal ligament; 5 - hook of the hamate; 6 - palmar carpometacarpal ligaments; 7 - palmar metacarpal ligaments; 8 - deep transverse metacarpal ligaments; 9 — metacarpophalangeal joint (opened); 10 — fibrous sheath of the third finger of the hand (opened); 11 - interphalangeal joints (opened); 12 - tendon of the muscle - deep flexor of the fingers; 13 - tendon of the muscle - superficial flexor of the fingers; 14 - collateral ligaments; 15 - carpometacarpal joint of the thumb (opened); 16 - capitate bone; 17 - radiate carpal ligament; 18 - radial collateral ligament of the wrist; 19 - palmar radiocarpal ligament; 20 - lunate bone; 21 - radius; 22 — interosseous membrane of the forearm; 23 - ulna
b - frontal cut of the left wrist joint and joints of the wrist bones), front view: 1 - radius bone; 2 - wrist joint; 3 - radial collateral ligament of the wrist; 4 - midcarpal joint; 5 - intercarpal joint; 6 - carpometacarpal joint; 7 - intermetacarpal joint; 8 - intercarpal ligament; 9 - collateral ulnar ligament of the wrist; 10 - articular disc; 11 - distal radioulnar joint; 12 - ulna
Human anatomy. S. S. Mikhailov, A. V. Chukbar, A. G. Tsybulkin; edited by L. L. Kolesnikova.
Hand joints and intercarpal ligaments
The wrist joint, articulatio radiocarpea, is formed by the carpal articular surface of the radius
and
the distal surface of the articular disc, representing
Articular capsule, capsula articularis,
thin;
is attached along the edge of the articular surfaces of the bones that form this joint. The joint is strengthened by the following ligaments:
• radial collateral ligament of the wrist, lig. collaterale carpi radiate.
Some of the bundles of this ligament reach the polygonal bone. The ligament inhibits adduction of the hand;
• ulnar collateral ligament of the wrist, lig. collaterale carpi ulnare.
The ligament inhibits abduction of the hand;
• dorsal radiocarpal ligament, lig. radiocarpeum dorsale.
The ligament inhibits flexion of the hand;
• palmar wrist ligament, lig. radiocarpeum palmare,
starts from the base of the lateral styloid process of the radius and the edge of the carpal articular surface of the same bone;
goes down and medially, attaching to the bones of the first and second rows of the wrist - scaphoid, lunate, triquetrum and capitate. The ligament inhibits the extension of the hand. The pisiform joint, articulatio ossispisifosmis,
connects the pisiform bone to the triquetrum.
Articular capsule, capsula articularis,
is fixed along the edge of the articular surfaces of the bones.
The joint cavity can communicate with the cavity of the wrist joint. The joint has the following ligaments:
• pisiform-hook, lig. pisohamatum;
• Pisiform metacarpal.
These ligaments are a continuation of the tendon of the flexor carpi ulnaris, m. flexor carpi ulnaris, in the thickness of which there is a large sesamoid bone - the pisiform bone, os pisiforme.
Sesamoid bones
They are small bone or fibrocartilaginous rounded formations located in the thickness of the tendons. These bones cause the corresponding muscle tendon to be lifted and create a more favorable angle of action on the bone.
Carpal bones
They form intercarpal joints among themselves, articulationes intercarpeae, and between the first and second rows of carpal bones there is a midcarpal
The joint is strengthened by the following ligaments:
• dorsal intercarpal ligaments, ligg. intercarpea dorsalicr,
• palmar intercarpal ligaments, ligg. intercarpea palmaria.
Some of the bundles of these ligaments start from the capitate bone and diverge in the form of rays to the bones of the first and second rows of the wrist, forming the radiate
carpi radiatum.
In addition to these ligaments, there are also interosseous intercarpal ligaments, ligg. intercarpea interossea.
Movements in the joint are sharply limited, so the midcarpal joint is classified as a low-moving joint. The carpometacarpal joints, articulationes carpometacarpeae, form the distal surfaces of the bones of the second row of the wrist and the base of the metacarpal bones.
There are two carpometacarpal joints.
• one is formed by the polygonal bone and the first metacarpal bone (thumb);
• the other is located between the polygonal bone, trapezoid, capitate and hamate bones, on the one hand, and the II-V metacarpal bones, on the other. Carpometacarpal joint of the hand, articulatio carpometacarpea pollicis,
formed by the distal saddle-shaped articular surface of the polygonal bone and the saddle-shaped articular surface of the base of the first metacarpal bone.
Carpometacarpal joint of the thumb
is a type of biaxial joint -
the saddle joint, articulatio sellaris.
Carpometacarpal joints of the II—V metacarpal bones
formed by the flat articular surfaces of the distal side of the polygonal bone, as well as the trapezoid, capitate and hamate bones and the proximal articular surfaces of the bases of the II-V metacarpal bones facing them.
The carpometacarpal joint of the fifth metacarpal bone is close in
the saddle joint, articulatio sellaris.
The articular capsule, capsula arlicularis, is attached to the edge of the articular surfaces of the bones and is tightly stretched.
The cavity of the carpometacarpal joint communicates with the cavity of the intercarpal, midcarpal and intercarpal joints. The ligamentous apparatus of the carpometacarpal joints includes
the palmar and dorsal
carpometacarpal
carpometacarpea patmaria et
dorsalia,
which on the corresponding side are stretched between the bones of the wrist and metacarpus.
The carpometacarpal joints are mechanically one whole - the solid base of the hand. They are inactive and belong to flat joints, articulationes planae. Intermetacarpal joints, articulationes intermetacarpeae, are formed by the lateral flat surfaces of the bases of the II-V metacarpal bones.
Articular capsule, capsula articularis,
attached along the edge of the articular surfaces.
The joint cavities in the proximal part communicate with the carpometacarpal joints.
The intermetacarpal joints include two groups of ligaments:
• four dorsal metacarpal ligaments, ligg. metacarpea dorsalia,
and three
palmar metacarpal ligaments, ligg.
metacarpea palmaria. These ligaments are located on the dorsal and palmar surfaces of the joints; they are stretched from the dorsal and palmar sides between the bases of the metacarpal bones;
• interosseous metacarpal ligaments, ligg. metacarpea interossea,
- located between the bases of the metacarpal bones.
The intermetacarpal joints are flat, low-moving joints.
Metacarpophalangeal joints, articulationes metacarpophalangeae, formed by the articular surfaces of the heads of the metacarpal bones
the articular surfaces of the bases of the first phalanges
facing them Articular capsules, capsulae articulares,
spacious.
They are strengthened in the lateral sections by collateral collateralia,
which start from the depressions on the ulnar and radial surfaces of the heads of the metacarpal bones and are attached to the lateral and partly palmar surfaces of the bases of the proximal phalanges.
Some of the fibers of these ligaments, starting from the lateral surface of the heads of the metacarpal bones, are directed to the palmar surface of the bases of the proximal phalanges, where they intersect with bundles of the same fibers of the opposite side. These ligaments are called palmar ligaments, ligg. palmaria
On the palmar surface of the joints, between the heads of the II-V metacarpal bones, deep
metacarpea transversa profunda.
The first metacarpophalangeal joint (thumb) belongs to the trochlear joints, gingfymus,
and the metacarpophalangeal joints of the II-V fingers are spherical
The interphalangeal joints of the hand, articulationes interphalangeae manus, are located between the adjacent phalanges of each finger. The articular surface of the head of each phalanx has
Ligamentous apparatus of the interphalangeal joints of the hand
represented by palmar
palmaria,
which come from the lateral surfaces of the blocks and are attached: some to the lateral surface of the bases of the phalanges (collateral ligaments), and others to their palmar surface.
The first (thumb) finger has one interphalangeal joint; interphalangeal joints of the II-V fingers are located between the proximal and middle phalanges and are called proximal interphalangeal joints;
the joints between the middle and
distal the distal
The interphalangeal joints are typical representatives of the trochlear joints, ginglymus.
How does the process develop?
There are three stages in the development of a wrist sprain:
- mild degree of damage - microtear of the ligament - moderate pain, no swelling;
- medium degree - partial tear - pain is felt clearly, mobility is limited, swelling and hemorrhage are present;
- severe degree - ligament rupture - extensive swelling and hematoma, severe sharp pain, movement is impossible.