104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 1 1 1 General Anatomy Three general principles are recognizable in the architecture of the human organism: 1. The principle of polarity: Polarity is reflected mainly in the formal and functional contrast between the head (predominantly spherical form) and the extremities (radially arranged skeletal elements). In the phylogenetic development of the upright position of the human body, polarity developed also among the extremities: The lower extremities provide the basis for locomotion whereas the upper extremities are not needed anymore for locomotion, so they can be used for gesture, manual and artistic activities. 2. The principle of segmentation: This principle dominates in the trunk. The anatomical structures (vertebrae, pairs of ribs, muscles, and nerves) are arranged segmentally and replicate rhythmically in a similar way. 3. The principle of bilateral symmetry: Both sides of the body are separated by a midsagittal plane and resemble each other like image and mirror-image. There are also different principles in the architecture and function of the inner organs: The skull contains the brain and the sensory organs. They are arranged like mirror and mirror-image and are the basis of our consciousness. Horizontal section through the head at the level of the eyes. The thorax contains the organs of the rhythmic system (heart, lung), which are only to some extent bilaterally organized. The conscious- ness (feeling, etc.) is located in- between. In the abdominal cavity, the most important abdominal organs (intesti- nal tract, liver, pancreas) are arranged unpaired. Their functions remain subconscious. Coronal section through the thoracic and abdominal cavity. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 2 2 Position of the lnner Organs, Palpable Points, and Regional Lines 1 B B AA 13 14 C C 2 4 3 5 6 15 7 8 16 D D 17 18 9 Position of the inner organs of the human body Regional lines and palpable points at the ventral side of the (anterior aspect). The main cavities of the body and their human body. contents. Regional lines A = parasternal line B = midclavicular line C = anterior axillary line D = umbilical-pelvic line The bones of the skeletal system are palpable through the localized. For better orientation, several lines of orienta- skin at different points. This enables physicians to localize tion are used, e.g., the parasternal line, the midclavicular the inner organs. On the ventral side, the clavicle, line, the anterior axillary line, the umbilical-pelvic line. sternum, ribs, and intercostal spaces are palpable. Further- By means of these lines, the heart and the position of the more, the anterior iliac spine and the symphysis can be vermiform process can be localized. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 3 Position of the lnner Organs, Palpable Points, and Regional Lines 3 EE F F 3 G 19 G 10 20 7 8 11 H H 21 22 12 Position of the inner organs of the human body Regional lines and palpable points at the dorsal side of the (posterior aspect). human body. Regional lines E = paravertebral line F = scapular line G = posterior axillary line H = iliac crest 1 Brain 2 Lung 3 Diaphragm 4 Heart 5 Liver 6 Stomach 7 Colon 8 Small intestine 9 Testis 10 Kidney 11 Ureter 12 Anal canal 13 Clavicle 14 Manubrium sterni 15 Costal arch 16 Umbilicus 17 Anterior superior iliac spine At the dorsal side of the body, the posterior spines of the 18 Inguinal ligament vertebral column, the ribs, the scapula, the sacrum, and 19 Scapular spine 20 Spinous processes the iliac crest are palpable. Lines of orientation are the 21 Iliac crest paravertebral line, the scapular line, the posterior axillary 22 Coccyx and sacrum line, and the iliac crest. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 4 4 Planes and Directions of the Body 1 A 3 4 Horizontal section through the pelvic cavity and the hip joints. 2 B Planes of the body: A = horizontal or axial or transverse plane B = sagittal plane (at the level of the knee joint) Directions: 1 = cranial 3 = anterior (ventral) 2 = caudal 4 = posterior (dorsal) MRI scan through the pelvic cavity and the hip joints (horizon- tal or axial or transverse plane). Sagittal section through the knee joint. MRI scan through the knee joint (sagittal plane). 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 5 Planes and Directions of the Body 5 1 2 A 5 B 6 3 4 Planes of the body: A = midsagittal or median plane B = frontal or coronal plane (through the pelvic cavity) Directions: 1 = posterior (dorsal) 4 = medial 2 = anterior (ventral) 5 = cranial 3 = lateral 6 = caudal MRI scan through the pelvic cavity and the hip joints (frontal or coronal Median section through the trunk of a female. plane). 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 6 6 Osteology: Skeleton of the Human Body 1 3 4 5 2 7 6 8 8 9 19 20 15 10 16 16 17 18 21 14 11 23 22 27 12 12 23 22 13 13 30 28 29 24 30 25 26 31 31 31 34 32 33 33 32 35 38 36 37 Skeleton of a female adult (anterior aspect). Skeleton of a female adult (posterior aspect). 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 7 Osteology: Skeleton of the Human Body 7 Axial skeleton Head 1 Frontal bone 1 2 Occipital bone 3 Parietal bone 4 4 Orbit 6 5 Nasal cavity 6 Maxilla 7 Zygomatic bone 8 8 Mandible 9 Trunk and thorax Vertebral column 15 9 Cervical vertebrae 10 Thoracic vertebrae 17 11 Lumbar vertebrae 12 Sacrum 21 13 Coccyx 14 Intervertebral discs Thorax 15 Sternum 11 16 Ribs 17 Costal cartilage 18 Infrasternal angle 22 23 Appendicular skeleton Upper limb and shoulder girdle 19 Clavicle 24 20 Scapula 25 21 Humerus 22 Radius 26 23 Ulna 24 Carpal bones 25 Metacarpal bones 31 26 Phalanges of the hand Lower limb and pelvis 27 Ilium 28 Pubis 34 29 Ischium 30 Symphysis pubis 31 Femur 32 32 Tibia 33 33 Fibula 34 Patella 35 Tarsal bones 36 Metatarsal bones 37 Phalanges of the foot 38 Calcaneus 35 36 37 Skeleton of a 5-year-old child (anterior aspect). The zones of the cartilaginous growth plates are seen (arrows). In contrast to the adult, the ribs show a predominantly horizontal position. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 8 8 Osteology: Bone Structure 1 2 1 1 3 3 3 4 MRI scan of the right femur and the hip X-ray of the right femur and the hip joint joint (coronal section) (from Heuck et al., (a.-p. direction). MRT-Atlas, 2009). 2 1 Head of the femur 5 2 Spongy bone ▲ Femur of the adult. Coronal section of the 3 Diaphysis of the femur proximal and distal epiphyses displaying the 4 Compact bone spongy bone and the medullary cavity. 5 Articular cartilage 1 1 2 2 4 4 Three-dimensional representation on the Coronal section through the proximal end trajectorial lines of the femoral head of the adult femur showing the characteristic (according to B. Kummer). structure of the spongy bone. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 9 Osteology: Ossification of the Bones 9 The ossification of the bones of the limbs starts within 3 the ossification centers of the primary cartilagenous 2 bones. Here, the medullary cavity develops. The ossifica- 4 tion process of limb bones is not finished at birth. 1 Ossification center in the 5 Lateral condyle ▲ ▲ head of the femur 6 Medial condyle 2 Greater trochanter 7 Intercondylar notch 3 Head of the femur 8 Diaphysis 4 Neck of the femur 8 7 6 5 Ossification of the femur (left: coronal section, right: posterior view of the femur). Arrows: distal epiphysis. X-ray of the upper and lower limb of a newborn child (left: upper limb, right: lower limb). Arrows: ossification centers. 1 Scapula 6 Radius 2 Shoulder joint 7 Tibia 3 Humerus 8 Fibula 4 Elbow joint 9 Knee joint 5 Ulna 10 Femur 1 Ulna 6 Fibula ▲ 2 Radius 7 Talus 3 Metacarpals 8 Calcaneus 4 Phalanges 9 Metatarsals 5 Tibia 10 Phalanges X-ray of hand and foot of a newborn. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 10 10 Arthrology: Types of Joints 4 1 Ball-and-socket joint with its different axes (schematic drawing). Arrows: axes of movement. 1 1 Humerus 2 Radius 3 Ulna 4 Articular cavity (shoulder joint) Shoulder joint as an example of a multiaxial ball- 5 Metacarpophalangeal joint 2 and-socket joint (coronal section). 6 Joints of fingers 3 1 1 3 2 2 3 Skeleton of the right arm and shoulder girdle (anterior aspect). Elbow joint with ligaments as an Coronal section of the elbow joint example of a hinge joint (monaxial (MRI scan, courtesy of Prof. Heuck, Munich). humero-ulnar joint) in combination The possibilities of movement are shown in the with a pivot joint (monaxial radio-ulnar schematic drawings on p. 11. joint), which allows rotation. 104750_S_001_018_Kap_1:_ 04.01.2010 12:55 Uhr Seite 11 Arthrology: Types of Joints 11 2 3 4 ✽ 1 Coronal section of the shoulder joint (MRI scan, from Heuck et al., MRT-Atlas, 2009). 5 6 6 Hinge joint (e.g. humero-ulnar joint). Left: extension, right: flexion. Arrows: axes of movement. Skeleton of right wrist and hand (medial aspect). The metacarpophalangeal joints are biaxial, as is the carpometacarpal joint of the thumb (✽ in the figure). The joints of the fingers, however, are monaxial.