Human joints

Synonyms

Joint head, socket, joint mobility, Medical: Articulatio

Number of joints

The number of human joints depends on whether you add up only real joints or all the articulated joints of the body. Real joints, i.e. joints that consist of two joint partners, are separated from each other by a cartilage-lined joint gap and have a joint capsule, there are about 100 in the human body. If you add all the joints, i.e. all the structures connected by ligaments, tendons or cartilage that allow movement, you get a total of about 360 joints.

For many people, this is an astonishingly high number, since the best-known joints are only dated to a number of six joints on each side of the body, i.e. twelve joints (shoulder, elbow, hand, hip, knee and foot joints). The far more numerous joints on the skull, spine, hands and feet are often not so well known to humans. Especially the joints on the trunk are not consciously moved and are not as openly visible as the large joints on the extremities.

Nevertheless they are essential for the mobility and flexibility of the human body. The inner clavicle joint (art. sternoclavicularis) consists of the joint surfaces of the clavicle.

They are both slightly saddle-shaped and do not fit exactly. This is compensated by a disc. Tight ligaments secure the joint and restrict mobility.

These are the The inner collarbone joint is the only bony connection between the shoulder girdle and the rib cage. The two main movements are the forward and backward movement and the raising and lowering of the shoulder. In addition, a rotation of the clavicle about its longitudinal axis.

  • Collarbone (clavicle) and the
  • Upper sternum (Manubrium sterni).
  • Anterior and posterior subclavian ligament (Ligg sternoclaviculare anterius and posterius)
  • The ligament between the two collarbones (Lig. interclaviculare) and
  • The rib clavicle ligament (Lig costoclaviculare).

The external clavicle joint (Art. acromioclavicularis) is also called the acromioclavicular joint.

It is the connection of the shoulder roof (acromion) with the clavicle (clavicula) and a flat joint that is connected by three taut ligaments. Here, there are sliding movements forward, backward, up, down and a rotation of the clavicle around its own axis.

  • The acromioclavicular subclavian ligament (Lig.

    acromioclaviculare)

  • The coraco-clavicularis ligament and
  • The coracoacromial ligament (Lig. coracoacromialis).

The shoulder joint (Art. humeri) is the most flexible and vulnerable joint of the body.

It is composed of: The joint surface is three to four times smaller than the joint head, which allows a great mobility but also a low stability. The acromion (Fornix humeri) serves as additional security for the head in the socket. This roof consists of: The capsule of the shoulder joint is wide and very thin at the back.

At the front, the capsule is reinforced with ligaments (Lig. glenohumerale). If the arm hangs down, a lower recess (Recessus axillaris) is formed, which allows for great mobility.

The joint capsule is connected to adjacent bursa (bursa subtendinea musculi subsacapularis and the bursa subcoracoideus) and within the capsule runs the tendon sheath of the long biceps tendon. Three degrees of freedom with six main movements are possible in the shoulder joint: The elbow joint (Art. cubiti) is a compound joint consisting of three partial joints: The upper arm joint is a hinge joint with one degree of freedom and two directions of movement, flexion and extension.

The upper arm spokes joint is a ball and socket joint in terms of its structure. Due to its ligamentous structures, only two degrees of freedom are possible. In addition to flexion and extension, which are performed together with the upper arm spoke joint, the joint also allows the inner and outer rotation (pro- and supination) of the forearm.

The elbow-spoke joint close to the body is a flat joint where the ulna and radius move. Three ligaments are crucial in the elbow joint. The wrist is composed of two joints.

The wrist close to the body is an egg joint with two degrees of freedom, the socket of which is formed by the radius, a disc which distributes the compressive forces evenly, and a stylus extension of the ulna. The head is formed by the scaphoid, the moon bone and the triangular bone of the carpal bones.The distal wrist is made up of the above mentioned carpal bones on the one hand and the remaining carpal bones, hook bone, head bone, small polygonal bone on the other hand. The joint gap is s-shaped, so that both rows of carpal bones are interlocked.

One speaks here of an interlocked hinge joint. Both joints form a functional unit during movements. The movements of the wrist are the flexion and extension and the lateral abduction.

Between the carpal bones there are tight ligament connections (amphiarthroses).

  • The head of the humerus (Caput humeri) and
  • The glenoid cavity of the shoulder blade (cavitas glenoidale).
  • The acromion (shoulder roof)
  • The raven beak process (Proc. coracoideus) and
  • The coracoacromial ligament (Lig.

    coracoacromialis).

  • The abduction (abduction) and
  • Introduction (adduction),
  • The bending (flexion) and
  • Stretching (extension) and the
  • Internal rotation and
  • External rotation.
  • The upper arm joint (Art. humeroulnaris),
  • The ellespoked joint close to the body (proximal radioulnar joint) and
  • The upper arm spoke joint (Art. humeroradialis).
  • The inner collateral ligament (Lig collaterale ulnare) and
  • The outer collateral ligament (Lig.

    collaterale radiale) stabilizes the joint and

  • The ring band (Lig. anulare radii), which runs in a ring around the head of the spoke and secures it in the joint.
  • On the one hand a wrist close to the body (Art. radiocarpea) and
  • The wrist remote from the body (Art.

    metacapea).

The thumb saddle joint (Art. carpometacarpalis polis) consists of It is a saddle joint with three degrees of freedom and thus six movements are possible: flexion, extension, spreading and approaching, and additionally the positioning and repositioning movement towards the little finger. The finger joints (Articulationes digitorum) are moved in: The basic joints (Articulationes metacarpophalangeae) are located between the heads of the metacarpophalangeal bones and the bases of the phalanges close to the body.

Both joint surfaces are cup-like and they are ball joints with two degrees of freedom. Bending, stretching, spreading and approaching are possible. The finger joints near and far from the body (Articulationes interphalangeales proximalis and distalis) are hinge joints with one degree of freedom and two movements, bending and stretching.

All carpal bones are connected by numerous ligaments. In addition, ligaments draw to the forearm and metacarpals. The ligaments strengthen the joint capsules in the upper areas.

They are divided into four groups according to their position and arrangement: the ligaments between the forearm and carpal bones, the ligaments between the carpal bones, the ligaments between the carpal and metacarpal bones, and the ligaments between the bases of the metacarpal bones. The sacroiliac joint (Articulationes sacroilacae) is formed by the two ear-shaped articular surfaces of the ilium and the sacrum. The cartilaginous surfaces are mountainous and thus well wedged into each other, so that only slight movements, tilting forward (nudation) and erection (counter-nudation) of the sacrum are possible.

The ligaments that secure the taut joint capsule are at the front: The hip joint (Art. coxae) consists of The hip joint is a nut joint. The joint surface of the socket is crescent-shaped (Facies lunatum) and encloses a pit filled with fatty tissue (Fossa acetabuli).

The joint surface is surrounded by a bony rim (Limbus acetabuli), on which a fibrous cartilaginous joint lip is located. The lower edge is incised (incisura acetabuli), which is spanned by a ligament (lig. transversum acetabuli).

All these structures ensure that the joint surface surrounds the joint head in a nut-shaped manner and encloses the freedom of movement. The joint capsule is relatively wide and encloses the head and most of the neck of the femur. It originates at the bony edge of the acetabulum and extends to the interhumeral line (Linea intertrochanterica or Crista intertrochanterica These three ligaments run helically and secure the head in the socket.

The femoral head band runs inside the joint capsule and extends from the femoral head cavity (fovea capitis) to the cavity of the acetabulum (fossa acetabuli). It does not have a stabilizing function, but serves as a vascular ligament for feeding the femoral head. With three degrees of freedom, the hip joint has six directions of movement: flexion, extension, approach and abduction, and rotation in and out.

  • The large polygon bone and
  • The first metacarpal bone.
  • The anterior sacroiliac ligament (Lig.sacroiliacae ventralia) and hinte
  • The posterior sacroiliac ligament (Lig. sacroiliacae dorsalia) and the interbony sacroiliac ligament (Lig. sacroiliacae interosseus).
  • In addition, the joint is formed by the iliolumbar ligament between the iliac crest and the last lumbar vertebral body,
  • The sacral ischial tuberosity ligament (Lig.

    sacrotuberale) from the sacrum to the ischium and the

  • Sacrospinal ligament (Lig. sacrospinale) from the sacrum to the tip of the ischium.
  • The hip socket (acetabulum) and
  • Femoral head (Caput ossis femoris).
  • Basic joints
  • Middle joints and
  • End joints divided.
  • The iliofemoral ligament from the posterior edge of the socket to the trochanteric fossa,
  • The ischiofemoral ligament from the posterior edge of the socket to the trochanteric fossa and
  • The pubic ligament (Lig. pubofemorale) from the upper pubic branch and radiates into the traits of the iliac ligament.

The knee joint (Art.

genus) is the largest joint in the human body. It is a compound joint and consists of the bones The tibia and thigh together form the tibiofemoral joint (Art. tibiofemuralis), while the thigh and kneecap together form the patellofemoral joint (Art.

patellofemuralis). The two joints are enclosed by a common joint capsule and are located in a joint cavity. In the tibio- femoral joint, the two spherical extensions of the thigh (condyles) and the hollowed plateau of the tibia (tibial plateau) form the joint surfaces.

The two menisci lie between them to compensate for unevenness between the two joint partners and to absorb pressure loads. Since there are two menisci, another distinction is made between two partial joints, the right and left meniscal tibial joint and the right and left meniscal femoral joint. Between the two joint surfaces of the tibial plateau there is a hump (Eminentia intercondylaris) to which the cruciate ligaments and the two menisci are attached.

In the femoral patellar joint, the patella and the thigh form the two joint partners. The base of the kneecap is round, while the bottom of the kneecap tapers to a point. The cartilage-covered joint surface is traversed by a ridge, so that it can slide between the two thigh extensions as if on a splint.

The joint capsule stretches from the dummy plateau to over the two thigh processes. The patella and patellar tendon are embedded in the front wall of the capsule. The joint capsule is connected at many points with the adjacent bursae, so that the capsule can unfold completely during all movements and allows the patella to glide undisturbed.

The ligamentous apparatus consists on the one hand of the two lateral ligaments. The inner ligament runs from the back above the inner thigh process to the inside front on the side of the shin plateau. It lies directly on the capsule and is fused with it and the meniscus below.

The outer collateral ligament runs from the front above the outer thigh process to the head of the fibula. It is not connected to the capsule. The two collateral ligaments lock the knee joint in an extended position the knee joint, so that no shear stress is allowed.

The two cruciate ligaments lie within the joint capsule, but are located between the two layers of the joint capsule. The anterior cruciate ligament comes from the tibial plateau at the front and pulls toward the inner surface of the outer thigh extension, while the posterior cruciate ligament comes from the tibial plateau at the rear and pulls toward the inner surface of the inner thigh extension. They allow contact between both joint partners in any joint position and prevent inward rotation when the knee is extended.

In the knee joint, two degrees of freedom with four movements are possible. The tibiofibular fibula connections are the tibial fibula joint close to the body and the tibial fibula joint remote from the body (Art. tibiofibularis proximales et distales).

These are plane joints in which only displacement movements are possible. The distal tibial fibula joint also plays a decisive role in the movements of the upper ankle joint. It forms the so-called ankle fork and thereby stabilizes the upper ankle joint.

Both joints are held together by tight ligaments. The upper ankle joint (Art. talocruralis), partly also known as the ankle joint, is formed by the distal ends of the tibia and fibula and by the trochlea tali of the ankle bone (talus).

This joint is the site of force transmission from the foot to the lower leg. The joint capsule originates from the cartilage-bone boundary and is thin and pliable in the frontal area.It is reinforced at the front by connective tissue structures that fix the tendons of the lower leg muscles. At the back and sides, the capsule is reinforced by ligaments.

The outer ligaments are the anterior and posterior talofibular anterior and posterior talofibular ligaments and the calcaneofibular ligament. The inner ligament is also called the triangular ligament (Lig. deltoideum) and consists of four parts, the upper ankle joint is a joint with one degree of freedom and thus two directions of movement, the lower ankle joint (Art.

talotarsalis) is a compound joint. Here the ankle bone (talus) articulates with the heel bone (calcaneus) and the scaphoid bone (Os naviculare). A distinction is made between two completely separate partial joints, which are called In the posterior joint chamber articulate the anklebone and the calcaneus, in the anterior joint chamber articulate the anklebone with an articular socket, which is formed by the heel bone, the scaphoid bone and the so-called acetabular ligament.

The acetabular ligament is a crucial ligament structure that contributes to the formation of the longitudinal arch. The joint capsule is thin and wide and is formed by the glenoid ligament on the one hand and by the strong intercostal-scaphoid-heelbone ligament (Lig. talocalcaneum interosseum) running within the joint on the other hand.

This ligament connects the talocalcaneum with the calcaneum and separates the joint into the two chambers. The ligament carries vessels that supply the ankle bone. Inside, outside and behind, the anterior chamber of the lower ankle joint is stabilized by the inner, outer and posterior ankle-heelbone ligament (Ligg.

talocalcaneum mediele, laterale et posterius). The joint capsule of the anterior chamber is stabilized at the back by the posterior talocalcanean ligament (Lig. talonaviculare dorsale).

On the outside, a v-shaped ligament runs from the calcaneus to the scaphoid and cuboid bone (Lig. bifurcatum). The lower ankle joint provides for a possible twisting of the foot.

Other joints of the foot are the Chopart joint is the joint lines of the scaphoid–heel bone and the heel bone – cuboid joint. With the help of this joint, the forefoot can be moved in flexion and extension and in rotation relative to the hindfoot. All other joints are fake joints due to tight ligament connections.

The toe joints are divided into the metatarsophalangeal joint (Art. metatarsophalangeae) and the middle and end joints (Art. interphalangeae proximales et distales).

The metatarsophalangeal joints consist of the cylindrical head of the metatarsal bones and the socket at the bases of the first toe bones and are enclosed by a wide joint capsule. The movements are like the movements of the basic finger joints. Functionally, the basic joints become hinge joints through taut collateral ligaments (Ligg.

collateralia). On the sole of the foot, the joint capsule is reinforced by taut ligaments (Ligg. plantaria).

The middle and end joints are classic hinge joints, where flexion and extension are possible. The strongest ligament on the side of the sole of the foot is the plantar ligament (Lig. planttare), which is important for tensioning the longitudinal arch.

  • Shinbone (Tibia)
  • Thigh (femur) and
  • Kneecap (patella).
  • Diffraction and
  • Aspect Ratio
  • Heel bone – cuboid bone joint (Art. Calcaneocubuidea),
  • The transverse tarsal joint or Chopart joint (Art. tarsi-transversa),
  • The sphenoid-navicular joint (Art.

    cuneonavicularis),

  • The joints between the sphenoid bones (Articulationes intercuneiformes)
  • The joint between the external sphenoid bone and cuboid bone (Art. cuneocuboidea) and
  • The tarsal–midfoot joints or also Lisfranc joints.
  • Diffraction,
  • Stretching and the
  • Bringing and taking apart and the
  • Rotation
  • Bending and
  • Stretching and the
  • Turning in and out.
  • The anterior and posterior tibio-occipital tibia (Pars tibiotalares anterius et posterius),
  • The tibionavicular part (Pars tibionaviculare) and the
  • Tibial-heel bone part (pars tibiocalcanea).
  • Posterior joint chamber (Art. subtalaris) and
  • Anterior joint chamber (Art. talocalcaneonaviculare)