Dr. Eng. Eiad Khalil email: [email protected] FB: Dr-e Khalil
Fourteenth Lecture
14. Musculoskeletal system (Cont’d)
Summary of previous lectures
In the previous lectures we talked about the basic elements of the medical word:
word root, combining form, suffix, and prefix. The meaning of a word is determined
by how these elements are combined. Detailed information about suffixes is
mentioned. Suffix linking and suffix types are explained in detail and many examples
related to the surgical, diagnostic, pathological, grammatical and plural suffixes are
also provided. Detailed information about prefixes is also mentioned. Prefix linking
and prefix types are explained in detail and many examples related to different
types of prefixes are provided.
The basic structural and functional organization of the body from the cellular level
to the organism level is also presented. Additionally, terms used to describe planes
of the body, body cavities, quadrants and regions of the abdominal cavity, and
divisions of the spinal column are presented. These terms are considered as an
essential part of medical terminology and are used in all body systems. We moved
on to talk about the body systems in detail.
Starting with the digestive system, also called the gastrointestinal (GI) system, it is
mentioned that it consists of a digestive tube called the GI tract or alimentary canal,
and several accessory organs whose primary function is to break down food,
prepare it for absorption, and eliminate waste. The GI tract, extending from the
mouth to the anus, varies in size and structure in several distinct regions. Many
terms related to the digestive system are also introduced.
Next, we talked about the respiratory system and how it is responsible for the
exchange of oxygen (O2) and carbon dioxide (CO2). Oxygen is carried to all cells of
the body in exchange for CO2, a waste product. The cardiovascular system helps in
this vital function by providing blood vessels for carrying these gases. Failure or
deficiency in either system has the same effect on the body: disturbance of
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homeostasis and O2 starvation in tissues that may cause death. The respiration
process and some medical word elements related to the respiratory system are also
introduced.
Later on we talked about the cardiovascular (CV) system and how it is composed of
the heart and blood vessels. The pumping action of the heart propels blood
containing oxygen, nutrients, and other vital products from the heart to body cells
through a vast network of blood vessels called arteries. Blood vessels include
arteries, veins and capillaries. The key terms related to the anatomy and physiology
of the cardiovascular system are also introduced. Specifically, the focus has been on
the terms related to the heart.
Finally, the musculoskeletal system has been introduced. It includes muscles, bones,
joints, and related structures, such as the tendons and connective tissue that
function in support and movement of body parts and organs. The key terms related
to the anatomy and physiology of this system are presented as well.
14.1. Introduction
In “Musculoskeletal system”, we talked about the anatomy and physiology of the
musculoskeletal system, focusing on the key terms related to the anatomy and
physiology of this system. In addition, the different types of muscles are explained.
In this lecture, the bones and some medical word elements related to the
musculoskeletal system are introduced.
14.2. Anatomy and Physiology
14.2.1. Bones252
Bones provide the framework of the body, protect internal organs, store calcium
and other minerals, and produce blood cells within bone marrow (haematopoiesis).
Together with soft tissue, most vital organs are enclosed and protected by bones.
For example, bones of the skull protect the brain; the rib cage protects the heart
and lungs. In addition to support and protection, the skeletal system carries out a
number of other important functions. Movement is possible because bones
provide points of attachment for muscles, tendons, and ligaments. As muscles
contract, tendons and ligaments pull on bones and cause skeletal movement. Bone
marrow, found within the larger bones, is responsible for haematopoiesis,
252 Medical Terminology Systems - A Body Systems Approach: Musculoskeletal Systems – Anatomy and Physiology – Bones p. 269
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continuously producing millions of blood cells to replace those that have been
destroyed. Bones serve as a storehouse for minerals, particularly phosphorus and
calcium. When the body experiences a need for a certain mineral, such as calcium
during pregnancy, and a sufficient dietary supply is not available, calcium is
withdrawn from the bones.
14.2.1.1. Bone types
There are four principal types of bone:
Short bones are somewhat cube shaped. They consist of a core of spongy bone,
also known as cancellous253 bone, enclosed in a thin surface layer of compact
bone. Examples of short bones include the bones of the ankles, wrists, and toes.
Irregular bones include the bones that cannot be classified as short or long
because of their complex shapes. Examples of irregular bones include vertebrae
and the bones of the middle ear.
Flat bones are exactly what their name suggests. They provide broad surfaces for
muscular attachment or protection for internal organs. Examples of flat bones
include bones of the skull, shoulder blades, and sternum254.
Long bones are found in the appendages (extremities) of the body, such as the
legs, arms, and fingers. (See Figure 14-1). The parts of a long bone include:
The (1) diaphysis255 is the shaft or long, main portion of a bone. It consists
of (2) compact bone that forms a cylinder and surrounds a central canal
called the (3) medullary256 cavity. The medullary cavity, also called
marrow cavity, contains fatty yellow marrow in adults and consists
primarily of fat cells and a few scattered blood cells.
The (4) distal epiphysis and (5) proximal epiphysis (plural, epiphyses) are
the two ends of the bones. Both ends have a somewhat bulbous257 shape
to provide space for muscle and ligament attachments near the joints.
The epiphyses are covered with (6) articular cartilage, a type of elastic
connective tissue that provides a smooth surface for movement of joints.
It also reduces friction and absorbs shock at the freely movable joints. In
addition, the epiphyses are made up largely of a porous chamber of (7)
spongy bone surrounded by a layer of compact bone. Within spongy bone
253 Cancellous: /ˈkænsələs/ of spongy or porous structure, as bone 254 Sternum: /ˈstɜːnəm/ (pl. sternums or sterna /ˈstɜːnə/) the breastbone 255 Diaphysis: /daɪˈæfɪsɪs/ 256 Medulla: /mɪˈdʌlə/ (pl. -las, -lae /-liː/) the innermost part of an organ or structure 257 Bulbous: /ˈbʌlbəs/ shaped like a bulb; round and fat in an ugly way
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is red bone marrow, which is richly supplied with blood and consists of
immature and mature blood cells in various stages of development. In an
adult, production of red blood cells (erythropoiesis258) occurs in red bone
marrow. Red bone marrow is also responsible for the formation of white
blood cells (leukopoiesis259) and platelets260.
Figure 14-1: Longitudinal structure of a long bone
The (8) periosteum, a dense, white, fibrous membrane, covers the
remaining surface of the bone. It contains numerous blood and lymph
vessels and nerves. In growing bones, the inner layer contains the bone-
forming cells known as osteoblasts261. Because blood vessels and
258 Erythropoiesis: /ɪˌrɪθrəʊpɔɪˈiːsɪs/ 259 Leukopoiesis: /luːkəʊpɔɪˈiːsɪs/ 260 Platelet: /ˈpleɪtlət/ a very small part of a cell in the blood, shaped like a disc. Platelets help to clot the blood from a cut or wound 261 Osteoblast: /ˈɒstɪəʊˌblæst/ a bone-forming cell
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osteoblasts are located here, the periosteum provides a means for bone
repair and general bone nutrition. Bones that lose periosteum through
injury or disease usually scale or die. The periosteum also serves as a point
of attachment for muscles, ligaments, and tendons.
14.2.1.2. Surface Features of Bones
Surfaces of bones are rarely smooth but rather consist of projections, depressions,
and openings that provide sites for muscle and ligament attachment. They also
provide pathways and openings for blood vessels, nerves, and ducts. Various types
of projections are evident in bones, some of which serve as points of articulation.
Surfaces of bones may be rounded, sharp, or narrow or have a large ridge.
Depressions and openings are cavities and holes in a bone. They provide pathways
and openings for blood vessels, nerves, and ducts. (See Table 14-1).
14.2.1.3. Divisions of the Skeletal System
The skeletal system of a human adult consists of 206 individual bones. However,
only the major bones are discussed. For anatomical purposes, the human skeleton
is divided into the axial skeleton and appendicular skeleton. (See Figure 14-2).
Axial Skeleton: The axial skeleton is divided into three major regions: skull, rib
cage, and vertebral column. It contributes to the formation of body cavities and
provides protection for internal organs, such as the brain, spinal cord, and
organs enclosed in the thorax. The axial skeleton is distinguished with bone
colour in Figure 14-2.
Table 14-1: the most common types of projections, depressions, and openings along with the bones involved, descriptions, and examples for each
Surface Type Bone Marking Description Example
Projections
Non-articulating surfaces
Trochanter262 Very large, irregularly shaped process263 found only on the femur264
Greater trochanter of the femur
262 Trochanter: /trəʊˈkæntə(r)/ any of several processes on the upper part of the vertebrate femur, to which muscles are attached 263 Process: /ˈprəʊses/ a natural outgrowth, projection, or appendage 264 Femur: /ˈfiːmə(r)/ (femoral /ˈfemərəl/ adj) the thigh bone
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Sites of muscle and ligament attachment
Tubercle265 Tuberosity266
Small, rounded process Large, rounded process
Tubercle of the femur Tuberosity of the humerus267
Articulating surfaces
Projections that form joints
Condyle Head
Rounded, articulating knob268 Prominent269, rounded, articulating end of a bone
Condyle of the humerus
Head of the femur
Depressions and openings
Sites for blood vessel, nerve, and duct passage
Foramen270 Fissure271 Meatus272 Sinus273
Rounded opening through and nerves a bone to accommodate blood vessels Narrow, slit-like opening Opening or passage into a bone Cavity or hollow space in a bone
Foramen of the skull through which cranial274 nerves pass Fissure of the sphenoid275 bone External auditory meatus of the temporal276 bone Cavity of the frontal277 sinus containing a duct that carries secretions to the upper part of the nasal cavity
265 Tubercle: /ˈtjuːbəkl/ a small round lump, especially on a bone or on the surface of an animal or plant 266 Tuberosity: /ˌtjuːbəˈrɒsɪtɪ/ any protuberance (/prəˈtjuːbərəns/ a round part that sticks out from a surface) on a bone, esp for the attachment of a muscle or ligament 267 Humerus: /ˈhjuːmərəs/ (pl. humeri /ˈhjuːməraɪ/) the large bone in the top part of the arm between the shoulder and the elbow 268 Knob: /nɒb/ a round lump on the surface or end of sth 269 Prominent: /ˈprɒmɪnənt/ sticking out from sth 270 Foramen: /fɒˈreɪmen/ (pl. -ramina /-ˈræmɪnə/, -ramens) a natural hole, esp one in a bone through which nerves and blood vessels pass 271 Fissure: /ˈfɪʃə(r)/ a narrow split or groove that divides an organ such as the brain, lung, or liver into lobes 272 Meatus: /mɪˈeɪtəs/ (pl. -tuses, -tus) a natural opening or channel, such as the canal leading from the outer ear to the eardrum 273 Sinus: /ˈsaɪnəs/ any of the hollow spaces in the bones of the head that are connected to the inside of the nose 274 Cranium: /ˈkreɪniəm/ (pl. craniums or crania /ˈkreɪniə/, cranial /ˈkreɪniəl/ adj) the bone structure that forms the head and surrounds and protects the brain 275 Sphenoid (bone): /ˈsfiːnɔɪd/ the large butterfly-shaped compound bone at the base of the skull, containing a protective depression for the pituitary gland 276 Temporal: /ˈtempərəl/ near the temple (/ˈtempl/ each of the flat parts at the sides of the head, at the same level as the eyes and higher) at the side of the head 277 Frontal: /ˈfrʌntl/ connected with the front part of the head
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Figure 14-2: Anterior view of the axial (bone coloured) and appendicular (blue coloured) skeleton
14.2.1.4. Skull
The bony structure of the skull consists of cranial bones and facial bones. (See
Figure 14-3). With the exception of one facial bone, all other bones of the skull are
joined together by sutures. Sutures are the lines of junction between two bones,
especially of the skull, and are usually immovable.
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Figure 14-3: Bony structures of the skull. (A) Cranial bones. (B) Facial bones
14.2.1.5. Thorax
The internal organs of the chest (thorax), including the heart and lungs, are
enclosed and protected by a bony rib cage. The thorax consists of 12 pairs of ribs,
all attached to the spine. (See Figure 14-4).
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Figure 14-4: Thorax
14.2.1.6. Vertebral Column
The vertebral column of the adult is composed of 26 bones called vertebrae278
(singular, vertebra). The vertebral column supports the body and provides a
protective bony canal for the spinal cord. A healthy, normal spine has four curves
that help make it resilient279 and maintain balance. The cervical and lumbar regions
curve forward, whereas the thoracic and sacral280 regions curve backward.
Abnormal curves may be due to a congenital defect, poor posture, or bone disease.
(See Figure 14-5).
278 Vertebra: /ˈvɜːtɪbrə/ (pl. vertebrae/ˈvɜːtɪbreɪ ; ˈvɜːtɪbriː/) 279 Resilient: /rɪˈzɪliənt/ returning to its original shape after being bent, stretched, or pressed 280 Sacrum: /ˈseɪkrəm/ (sacral: /ˈseɪkrəl/ adj) a bone in the lower back, between the two hip bones of the pelvis
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Figure 14-5: Lateral view of the vertebral column
14.2.1.7. Pectoral281 (Shoulder) Girdle282
The pectoral girdle consists of two bones, the anterior (1) clavicle283 (collarbone)
and the posterior (2) scapula284 (triangular shoulder blade). (See Figure 14-2). The
primary function of the pectoral girdle is to attach the bones of the upper limbs to
the axial skeleton and provide attachments for muscles that aid upper limb
movements. The paired pectoral structures and their associated muscles form the
shoulders of the body.
281 Pectoral: /ˈpektərəl/ of or relating to the chest, breast, or thorax 282 Girdle: /ˈɡɜːdl/ the bony framework that unites the upper or lower extremities to the axial skeleton 283 Clavicle: /ˈklævɪkl/ = Collarbone: /ˈkɒləbəʊn/ either of the two bones that go from the base of the neck to the shoulders 284 Scapula: /ˈskæpjʊlə/ (pl. scapulae /ˈskæpjʊliː/ or scapulas) = shoulder blade: either of the two large flat bones at the top of the back
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14.2.2. Medical Word Elements285
This section introduces combining forms, suffixes, and prefixes related to the
musculoskeletal system. Word analyses are also provided.
Element (Meaning) Word (Arabic286) Pronunciation287 Analysis
Combining Forms
Skeletal System:
arthr/o (joint)
arthr/itis ( المفاصل التهاب )
ɑːθraɪtɪs inflammation of a joint -itis: inflammation
brachi/o (arm)
brachi/algia ( عضدي ألم )
ˈbreɪkiˈældʒiə pain in the arm -algia: pain
cephal/o (head)
cephal/ad (رأسي ا)
ˈsefəˌlæd toward the head -ad: toward
cervic/o (neck; cervix uteri (neck of uterus))
cervic/o/dynia ( قبة ألم الر )
ˌsɜːvɪkəˈdɪniə pain in the neck; also called cervical neuralgia -dynia: pain
cost/o (ribs)
cost/ectomy ( لع قطع الض )
kɒˈstektəmi excision of a rib -ectomy: excision, removal
crani/o (cranium (skull))
crani/o/tomy ( القحف حج )
ˌkreɪnɪˈɒtəmi incision of the cranium -tomy: incision
femor/o (femur (thigh bone))
femor/al (فخذي )
ˈfemərəl pertaining to the femur -al: pertaining to
fibul/o (fibula (smaller bone of lower leg))
fibul/o/calcane/al ( عقبي شظوي )
ˌfɪbjələˈkælkeɪniːəl pertaining to the fibula and calcaneus calcane: calcaneum288 (heel bone) -al: pertaining to
humer/o (humerus (upper arm bone))
humer/o/scapul/ar ( ي كتف عضدي )
hjuːmərə-ˈskæpjʊlə(r)
relating to the humerus and scapula scapul: scapula (shoulder blade) -ar: pertaining to
metacarp/o (metacarpus289 (hand bones))
metacarp/ectomy ( نع استئصال الس )
ˌmetəˈkɑːpektəmi excision of metacarpal bone(s) -ectomy: excision, removal
285 Medical Terminology Systems - A Body Systems Approach: Musculoskeletal Systems – Anatomy and Physiology – Medical Word Elements p. 278 286 http://www.emro.who.int/Unified-Medical-Dictionary.html 287 Oxford Advanced Lerner’s Dictionary, 8th ed. or: http://dictionary.reference.com/ 288 Calcaneum: /kælˈkeɪniəm/ 289 Metacarpus: /ˌmetəˈkɑːpəs/
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metatars/o (metatarsus290 (foot bones))
metatars/algia ( المشط ألم )
ˌmetətɑːˈsældʒiə pain in the metatarsus -algia: pain Metatarsalgia emanates from the heads of the metatarsus and worsens with weight bearing or palpation291.
orth/o (straight)
orth/o/ped/ist ( اح العظام تقويم جر )
ˌɔːrθəˈpiːdɪst specialist in treatment of musculoskeletal disorders ped: foot; child -ist: specialist Initially, an orthopaedist corrected deformities and straightened children’s bones. In today’s medical practice, however, the orthopaedist treats musculoskeletal disorders and associated structures in persons of all ages.
oste/o (bone)
oste/oma ( عظمي ورم )
ˌɒstɪˈəʊmə tumour composed of bone -oma: tumour Osteomas are benign bony tumours.
radi/o (radiation, x-ray; radius (lower arm bone on thumb side))
radi/al ( كعبري ،شعاعي )
ˈreɪdiəl pertaining to the radius -al: pertaining to
thorac/o (chest)
thorac/o/dynia ( در ألم الص )
ˌθɔːrəˈkɒdɪniə pain in the chest -dynia: pain
vertebr/o (vertebrae (backbone))
inter/vertebr/al ( الفقرتين بين )
ˌɪntərˈvɜːtɪbrəl relating to the area between two vertebrae inter-: between -al: pertaining to The combining form vertebr/o is used to indicate anatomical terms.
Muscular System:
muscul/o (muscle) my/o
muscul/ar (عضلي )my/oma ( عضلي ورم )
ˈmʌskjələ(r) maɪˈəʊmə
pertaining to muscles -ar: pertaining to tumour of muscle (tissue) -oma: tumour
290 Metatarsus: /ˌmetəˈtɑːsəs/ 291 Palpate: /pælˈpeɪt/ to examine part of the body by touching it
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Suffixes
-clasia (to break; surgical fracture)
oste/o/clasia ( العظم نقض )
ˌɒstɪˈɒkleɪsiə surgical fracture of a bone oste/o: bone Osteoclasia is the intentional fracture of a bone to correct a deformity and is also called osteoclasis.
-desis (binding, fixation (of a bone or joint))
arthr/o/desis (إيثاق المفصل)
ɑːˈθrɒdəsɪs binding together of a joint arthr/o: joint
-scopy (visual examination)
arthr/o/scopy ( المفصل تنظير )
ɑrˈθrɒskəpi visual examination of a joint arthr/o: joint Arthroscopy is an endoscopic examination of the interior of a joint. It is performed by inserting small surgical instruments to remove and repair damaged tissue, such as cartilage fragments or torn ligaments.
Prefixes
a- (without, not)
a/trophy (ضمور)
ˈætrəfi without nourishment -trophy: development, nourishment Atrophy is a wasting or decrease in size or physiological activity of a part of the body because of disease or other influences.
dys- (bad; painful; difficult)
dys/trophy (حثل)
ˈdɪstrəfi disorder caused by defective nutrition or metabolism -trophy: development, nourishment
sub- (under, below)
sub/patell/ar ( ضفة حت ت الر )
sʌbpəˈtelə(r) pertaining to below the patella patell: patella292 (kneecap) -ar: pertaining to
supra- (above; excessive; superior)
supra/cost/al ( لع فوق الض )
ˌsuːprəˈkɒstl pertaining to above the ribs cost: ribs -al: pertaining to
292 Patella: /pəˈtelə/ (pl. patellae /pəˈteliː/) the kneecap
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syn- (union, together, joined)
syn/dactyl/ism ( األصابع ارتفاق )
ˈsɪndəktɪlɪzəm condition of joined fingers or toes dactyl: fingers, toes -ism: condition Syndactylism is a fusion of two or more fingers or toes.
End of lectures
Dr. Eng. Eiad Khalil