BONES AND CARTILAGES
Bones and cartilages are specialized connective tissue known as sclerous tissue; bones consist of bone cells (osteoblast—bone forming cells, osteocyte—mature cells, osteoclast—bone destroyer which helps in maintaining the shape of bone) and calcified matrix. As it has rich blood supply, bone can repair much more rapidly than cartilage. Lymphatics are absent in bone marrow.
FUNCTION OF BONE
- Provides mechanical support
- Gives attachment to the muscle
- Constitutes leverage action for augmentation of movement, and
- Is store house of bone marrow.
In case of adult, the site of bone marrow is withdrawn from the manubrium sterni and iliac crest.
METAPHYSIS (SHORT NOTES)
The epiphyseal end of diaphysis of growing bone is known as metaphysis. It is the most growing region of the bone.
- Its width is greater than any other part of the diaphysis.
- It is the vascular zone of the growing long bone.
- Infection of the growing long bone starts from here and gives rise to osteomyelitis. It is due to hairpin-like bend of the arteries (site of bacterial enlodgement).
- Metaphysis gives attachment to capsules, ligaments and sometimes muscles; so it is always subjected to stress and strain and hence become weak and damaged.
- Infection of metaphysis is common in children and known as osteomyelitis.
LAW OF UNION OF EPIPHYSIS AND THE GROWING END OF LONG BONE
The law states that the ends of long bone where ossification starts first unite last with the diaphysis and vice versa. So where the ossification starts first is the growing end of the long bone. The growing end lies opposite end of nutrient artery. In milking cow position the direction of artery is always downwards.
DEGENERATION OF ARTICULAR CARTILAGE RESULTS IN OSTEOARTHRITIS
Osteoarthritis is due to degeneration of articular cartilage. This cartilage lacks regeneration because it is devoid of pericondrium. The degeneration of articular cartilage causes difficulty in walking, if it affects the weight-bearing joint like hip and knee.
- Effect of exercise and mechanical stress on bone tissue: Within limit bone has an ability to alter its strength in response to changes to mechanical stress. Another effect of stress is increased production of calcitonin-hormone that inhibits bone reabsorption. Removal of mechanical stress results in demineralization of bone. Main mechanical stresses are those that result from pull of skeletal muscle and pull of gravity. Athlete's bone is stronger and thicker than nonathlete.
- In whole span of life, male loses 15% of skeletal mass and female loses 30% of skeletal mass.
- Vitamin D deficiency produces rickets in children. Vitamin D deficiency affects the mineralization of osteoids (Haversian system). There is poor absorption of calcium and in turn poor mineralization. There is bowing of legs and knocking of knees due to less strength of bone in children (Figs 1.2A and B).
- Osteoporosis: Reduction of quality of bones both due to reduction of bony minerals and protein content (occurs in old age). It is more common in female in menopausal age group.
- Fracture of bone: It may be partial or along the whole thickness.
Types of Epiphysis (Fig. 1.3, Short Note)
- Pressure epiphysis: It bears weight, e.g. head of femur, humerus.
- Traction epiphysis: It develops due to muscle pull, e.g. lesser tubercle of humerus is formed by pull of subscapularis.
- Atavistic epiphysis: Ancient history says it is a separate piece of bone but adheres to the host bone for nutrition, e.g. coracoid process of scapula, posterior tubercle of talus.
Ossification (Fig. 1.4, Short Note)
The term ossification means bone formation. The bone formation starts in the embryonic period from a variety of preformed model. The model may be membranous, cartilaginous or membranocartilaginous. When ossification occurs in membranous model it is known as membranous ossification and when it occurs in cartilaginous model it is known as endochondral or cartilaginous ossification. In the developing bone, in the region of shaft, first there is proliferating zone, second zone is the zone of maturation. The third zone is the zone of hypertrophy.
The hypertrophic cartilage suffers from nutrition and death of cartilage occurs. This produces a gap known as primary areolae. This region is invaded by a blood vessel containing osteoblastic cells and osteoclasts. Thus, bone formation starts and it will gradually strengthen the broken model. The artery that enters into the primary areolae is known as nutrient artery. Osteoblasts deposit bone in a lamellar fashion. Osteoclasts is the bone destroyer, remodeled the shape of the bone.
Clinical Anatomy of Bones (in General)
Union of Fracture
During fracture there is bleeding at fracture site. It is organized as clot. The clot bridges end to end of the site of fracture. Fibroblasts invade the site and there is formation of granulation tissue (young vascular tissue). It will be changed into bony callus (young bone) and union takes place. The most common cause of thickening of bone is callus (Figs 1.6A to D).
- Plaster or cast applied to heal fracture should not be removed before 6 weeks.
- Union of bone is rapid than cartilage. So, bone repair is rapid than cartilage.
- Greenstick fracture in children is common because of less deposition of inorganic material.
Joints are defined as junction between two or more bones or bones and cartilage or between two cartilages.
Characteristics Features of Synovial Joints
- Wide range of movement is there.
- Bony surface is covered by hyaline cartilage.
- Presence of fibrous capsule which is lined by synovial membrane.
- Joint cavity is flushed by synovial fluid which is rich in hyaluronic acid and which nourishes the avascular articular cartilage.
Blood Supply of a Joint
Epiphyseal vessels enter the long bone at near the attachment of capsule and give anterior branch which ramify in plexus over synovial membrane. It is seen application of temperature or pressure around a joint, reflexly after the blood flow. Hence, massage is important in case of child as well as in patient with disease.
Nerve Supply of a Joint
Segmental innervation of muscles regulate joint movement. Lasts formulation says four contiguous spinal segment regulate movement of particular joint. Upper two control flexion, adduction, medial rotation. Lower two control extension, abduction, lateral rotation.
Articular nerves contain sensory and autonomic fibers.
- Hilton's law: The law states that the nerve supply of a joint comes from nerve supply of nearby muscle and that nerve also supplies the skin over the joint. Therefore, in joint diseases irritation of nerve causes reflex spasm of muscles and referred pain to the skin overlying the muscles.
Physiology of Joint Motion
- Depending on motion by synovial fluid: The synovial fluid movement occurs by the compression of all articular cartilages and capsules.
- Extensibility: Joint mobility maintains the extensibility of articular tissue. If the joint is immobilized, the ligaments, tendons and cartilage loose its extensibility property and it leads to joint stiffness and hypomobility.
Factors that Limit the Range of Joint Motion
It depends not only on the bony configuration but also on muscle, ligaments and soft tissue envelop. These structures, lead to improper functioning of the joint in disease.
STABILIZING FACTOR OF JOINT (SHORT NOTE)
- Shape of articular surface of opposing bones
- Strength of capsular and intracapsular ligaments
- Strength of surrounding muscles of the joint
- Strength provided by rims of cartilage (glenoid labrum)
CERTAIN IMPORTANT THINGS ABOUT JOINTS
- 0 position: This is starting position of a joint. In case of shoulder, joint is arm located by the side of chest wall. Always start examination of joint from 0 position.
- Joint articular surfaces are avascular and it receives nutrition from synovial fluid.
- Closed pack position: In this position, the joint surfaces are congruent (fits with each other), the ligaments are tight. In this position, dislocation is rare. But damage of intra-articular structure is more common in closed pack position.
- Loosed pack position: Any position other than closed pack position is known as loose pack position of joint.
CLINICAL ANATOMY (JOINTS)
Common Joint Injuries
It is a condition where the ligaments reinforcing a joint are stretched or torn. The lumbar region, the knee and ankle are common sites of sprain. RICE; R—for rest; I—for ice, C—for compression and E—for elevation, are the standard treatment for pulled muscle, stretched tendons or ligaments. Torn ligament do not heal well.
Cartilage Injuries (Figs 1.7A to C)
- It is common in knee joint, particularly in case of sportsman due to twisting force.
- The avascular cartilage (medial menisci) is unable to repair itself.
Dislocation (Fig. 1.8)
- It involves displacement of articular surfaces of bones.
- It is usually accompanied by sprains, inflammation, and joint immobilization, like fracture, dislocation must be reduced (go back to original position). Shoulder joints, finger joints, thumb, patella and temporomandibular joint are commonly dislocated.
- Subluxation is the partial dislocation of a joint. Shoulder joint is commonly subluxated due to loose capsule on inferomedial aspect.
- Temporomandibular joint is also dislocated due to loose capsule; even a large yawning produces dislocation. Anterior dislocation of this joint is common. Acromioclavicular joint is also commonly dislocated.
Epiphyseal injury occurs in growing long bone. The injuries occur through the weakest area of epiphysis (i.e. through the zone of hypertrophic cartilage). Epiphyseal injury may often be missed as fracture. To clear the doubt (in children), both sided X-ray must be taken for comparison.
Inflammation and degenerative disease of joint includes bursitis, tendinitis and various forms of arthritis.
- Most common degenerative joint disease accompanied by stiffness, pain and discomfort.
- Most common in aged (above 40 years) particularly in women. It is due to wear and tear of articular cartilage and bone demineralization.
- Weight-bearing joints are mostly affected, e.g. knee joint.
- Rheumatoid arthritis:
- Occurs in any age group (three times more in female).
- It is most crippling arthritis (due to autoimmune disease) involving severe inflammation of joints.
- Small joint like, joint of finger, wrist, ankle and feet are affected in the same time (both sides are involved).
- Joint replacement: It is a procedure of total or partial replacement of diseased joint by prosthesis (artificial aid). It is most commonly done in knee, hip and shoulder joints. Lifespan of prosthesis is 10–15 years (Fig. 1.9).
Q. Greenstick fracture of bone in children? Explain.
Ans. In children, bone cells and collagen fibers are more and minerals and calcium are less. So, bones in case of children are more elastic and the fracture is not involving the full thickness of bone and is known as greenstick fracture.
Must Know Factor of Joint
- Joints are of three varietiess: (1) fibrous, (2) cartilaginous, and (3) synovial.
- All synovial joints possess (1) a cavity enclosed by (2) a fibrous capsule, which is lined inside by (3) synovial membrane.
- Factors maintaining the stability of the joints are: (1) bony configuration, (2) ligaments, and (3) muscles surrounding the joints (e.g. shoulder joint).
Muscle (mouse-like appearance) tissue has the special property of contractility due to presence of abundant actin and myosin protein filament. Muscle cells are known as myocytes. In men, muscle tissue constitutes 40–50% of body mass. All the muscles of body are developed from mesoderm except muscles of hair follicle (arrector pili), muscles of iris which developed from ectoderm. It is important to know that blood flow in skeletal muscle is extremely changeable and varies with muscle activity. Muscles and nerve can tolerate 6 hours of ischemia (lack of blood supply), after that muscle is replaced by connective tissue which reduces the power of muscle. There are three types of muscles (Table 1.3).
PENNATE MUSCLE (SHORT NOTES)
Muscle tissue has got the property of contractility. According to orientation of muscle fibers, there are different varieties of muscles. Pennate muscle is one of them. The orientation of its fibers resemble that of a feather, hence the name. Here the muscle fibers are so arranged that their pull is oblique. They are attached to the sides of a tendon. There are different types of pennate muscles (Fig. 1.13):
- Unipennate: The muscle fibers are oblique and attached to one side of the tendon, e.g. flexor pollicis longus.
- Bipennate: The oblique muscle fibers are attached on both sides of the tendon giving a feathery appearance, e.g. interosseous muscle.
- Multipennate: More than one bipennate muscle fibers lie side by side, e.g. deltoid.
- Circumpennate: The muscle fibers originate from periphery and converge obliquely on central tendon, e.g. tibialis anterior.
- Effect of exercise on muscles:
- Regular aerobic exercise results in increased efficiency endurance (tolerance), strength, and resistant to fatigue of skeletal muscles.
- Resistance exercise causes skeletal muscle hypertrophy (increase in size) and gains in skeletal muscle strength.
- Cramp: Sustained spasm of an entire muscle (lasts for a few seconds to several hours) causing the muscle to become tough and painful; common in calf, thigh and hip muscle.
- Spasm: A sudden involuntary muscle twitch (range from mere irritation to very painful) due to chemical imbalance; common in eyelid, facial muscle.
- Muscle strain: Excessive stretching and forcible tearing (due to overuse and abuse)—the injured muscle is painful and inflamed. Quadriceps and hamstring muscle strain are very common in athletes.
- Muscle injury: Very common; formation of hematoma (blood accumulated swelling) within the muscle, e.g. hamstring, gastrocnemius hematoma.
- Wasting: Wasting due to disuse and confinement in bed due to peripheral nerve injury.
- Muscle atrophy: When the motor nerve supply of a muscle is destroyed, the muscle undergoes atrophic and degenerative changes.
Common patterns of muscle fascicle arrangement are strap, quadrilateral, fusiform, triangular, pennate, spiral, etc. Muscles with parallel fibers shorten most. Pennate muscles shorten less.
Classification of voluntary muscle (according to shape and direction of muscle fibers) has been shown in Figure 1.14.
PARALLEL MUSCLE (SHORT NOTES)
The muscles fibers are parallel to the line of the pull. The fibers are long but their numbers are relatively few.
Parallel muscles are divided into following subtypes (Fig. 1.15):
- Quadrilateral, e.g. quadratus lumborum
- Strap muscle, e.g. sartorius
- Strap with tendinous intersections, e.g. rectus abdominis
- Range of movement is more due to the mere length of fibers
- Force of contraction is less due to less number of muscle fibers.
The nervous system is controlling and communicating system of our body. Its main functions are to monitor, integrate, and response to information on the environment.
It is divided into two major parts: (1) central nervous system (CNS) (including brain and spinal cord) and (2) peripheral nervous system (PNS) (12 pairs of cranial nerves, 31 pairs of spinal nerves and their associated ganglia).
Functionally, the nervous system is again divided into somatic nervous system (which controls voluntary function) and autonomic nervous system (ANS) (control involuntary function).
Histology of Nervous Tissue
The structural and functional unit of nervous system is neuron (Fig. 1.16). They have a cell body and cytoplasmic processes called axon and dendrites. All neurons have one axon with few exceptions.
Axon transmits impulse away from nerve cell. The axon hillock is the most excitable part of the axon. The axon ends in enlarged terminals which secretes neurotransmitter. The large axons (nerve fibers) are myelinated. Myelination is done by Schwann cell in PNS and oligodendrocyte in CNS. In some places, the myelin sheath is absent known as nodes of Ranvier. The purpose of myelination is propagation of wave of excitation rapidly and also insulation. Myelinated nerve fibers are seen in muscles where reaction speed is needed; whereas unmyelinated fibers occur in transmission of visceral pain.
These are the supporting cells of CNS. There are different types of neuroglial cells:
- Astrocytes: They are concerned with the nutrition of the nervous tissue. They are of two types:
- Protoplasmic astrocyte
- Fibrous astrocyte.
- Oligodendrocytes are like Schwann cells. They myelinate the CNS.
- Microglia: Their action is that of macrophages.
- Ependymal cells: They are short columnar cells lining the cavities of CNS.
- Proliferation of glial cells is called “gliosis”. A CNS lesion is healed by gliosis.
- Tumor of the glial cells is the most common tumor of CNS.
Spinal nerves are united ventral and dorsal roots, attached in a series, to the side of the spinal cords. They are 31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. These emerge through intervertebral foramina. Except T2-T12, all ventral rami join one another forming nerve plexuses. This plexuses occur in the cervical, brachial, lumbar and sacral regions.
AUTONOMIC NERVOUS SYSTEM
It is the part of nervous system that controls automatic activity of our body (i.e. involuntary activity) like heart, smooth muscles and gland. It is divided into two parts—sympathetic and parasympathetic and both parts have afferent and efferent nerve fibers.
Sympathetic Trunk (Fig. 1.17)
They lie on either side of vertebral column; extends from base of the skull to the coccyx. It looks like a knotted thread. There are three cervical ganglia: (1) superior cervical ganglia (largest, formed by the fusion of upper four cervical ganglia), (2) middle cervical ganglia (smallest of the three, formed by the fusion of fifth and sixth cervical ganglia) and (3) inferior cervical ganglia (intermediate in size, formed by the fusion of seventh and eighth cervical ganglia.
This ganglia lies between carotid sheath and prevertebral fascia, eleven thoracic, four lumbar, four sacral ganglia. The sympathetic ganglions are structures where synapse (white rami) between pre- and postganglionic fiber takes place. The right and left trunk coverage medially and form ganglion impar (unpaired) in front of coccyx. Most preganglionic fibers reach the sympathetic trunk; they have three types of termination:
- The fibers may ascend high up and terminate in cervical ganglia or lower fiber may descend down in lower lumbar and sacral ganglia.
- Some of the preganglionic fibers may pass through the ganglia on thoracic part of sympathetic trunk without synapsing. These fibers form three splanchnic nerves.
- Greater splanchnic nerve: Arise from fifth to ninth thoracic ganglia pierces the diaphragm and synapses (neuroneuronal junction) with celiac plexus.
- Lesser splanchnic nerve: Arise from tenth and eleventh thoracic ganglia, pierces diaphragm and synapses with lower part of plexus.
- Least splanchnic nerve: Spinal nerves correspond to the same segment of spinal cord, but the sympathetic pathways do not correspond with the segment of spinal cord.
- T1 segment—passes up and goes to head region
- T2 segment—goes to neck
- T3-T6 segment—into thorax
- T7-T11 segment—for abdomen
- T12-L2 segment—for leg
According to some author, the parasympathetic system is represented as D division [i.e. digestion, defecation, diuresis (urination)]. The sympathetic system is represented as E division (i.e. excitement, exercise, embarrassment and emergency). Autonomic function is controlled at different levels: (1) reflexes are controlled at spinal cord and brainstem level, (2) hypothalamus controls the integration with autonomic, somatic and endocrine response, and (3) frontal lobe of cerebral cortex controls ANS at subconscious level via limbic connections. The efficiency of ANS decreases in old age.
Preganglionic fibers are cholinergic in both sympathetic and parasympathetic; postganglionic sympathetic fiber is adrenergic except for sweat gland and arrector pili muscle. Postganglionic neuron of parasympathetic is cholinergic. Parasympathetic is essential for life.
Autonomic nervous system is involved in every important process that goes in our body. Most autonomic disorders reflect, excess, or deficient controls of smooth muscle activity. Unlike CNS, the ANS can be easily and effectively controlled by drugs.
- Hypertension (high blood pressure): It may result from excessive sympathetic activity. It is known as stress-induced hypertension.
- Vaso-occlusive disease: They are Raynaud's disease affecting the upper limb, Buerger's disease affecting the lower limb. It is characterized by gradual cyanosis (bluish coloration); pain in the affected region in severe cases gangrene (tissue death) may result. To treat severe cases, sympathectomy (cutting of sympathetic trunk in a particular segment) is done. The involved vessels dilate, re-establishing adequate blood supply to the affected region.
- Congenital megacolon (Hirschsprung's disease): In this condition, parasympathetic innervation of the distal part of colon fails to develop. As a result, distal colon is immobile and dilated. The condition is corrected surgically.
- Achalasia (not relaxed): A condition where esophagus is unable to propel food in the lower part due to parasympathetic neuron deficiency. The distal esophagus becomes dilated and vomiting is common.
- Horner's syndrome: It results from an interruption of the sympathetic nerve supply to head and neck. The affected person exhibits constriction of pupil (myosis), slight drooping of eyelid (ptosis), vasodilatation of skin arterioles (flashing of face) and loss of sweating (anhidrosis). Common sites of lesion are brainstem, cervical part of spinal cord or stellate ganglion.
All animals and human being require a mechanism to distribute oxygen and nutrition throughout the tissues of body and to collect waste product and carbon dioxide from the tissues. So, there is requirement of blood—vascular system. It requires a muscular pump—the heart. Various types of blood vessels like (1) arteries, (2) arterioles (3) capillaries, (4) sinusoids, (5) venules, and (6) veins are present within the body.
- Arteries: Arteries are of three types:
- Elastic or large size arteries: Here tunica media (middle coat) contains more elastic tissue, e.g. aorta, carotid, subclavian, axillary, and common iliac arteries.
- Muscular or medium size arteries: Most widely distributed. Tunica media consists of predominantly muscle fiber, e.g. brachial, radial, femoral, gastric, superior mesenteric arteries.
- Arteriole: It is the smallest arteries having a diameter of 100 micron. They act as resistant vessel to maintain peripheral blood pressure.
- Capillaries: Primary exchange vessel. Carry blood from arteriole to venule. Arteriole, capillaries and venules together constitutes microcirculation.
- Sinusoids: Large lumen and tortuous course. Absent or incomplete basement membrane. Very porous (Table 1.4).
Angiogram: Visualization of arterial tree by radiopaque dye is known as angiogram.
At the upper limb brachial artery (just above the cubital fossa) and radial artery (region where radial pulse is felt) are the common site, common carotid artery in neck (near its bifurcation) and femoral artery in lower limb (just below the inguinal ligament) in the site of choice for angiography (Fig. 1.19 and Table 1.5). Various regions in the body where arterial pulsations can be felt are shown in Figure 1.19.
TERMINOLOGY USED IN DESCRIPTION OF BLOOD VESSELS
- Angina pectoris: Chest pain
- Artery: Carries more oxygenated blood away from the heart
- Embolous: Plug
- Infarction: Virtually blood less area
- Ischemia: Lacking adequate blood supply
- Stenosis: Narrowing
- Vein: Carries poorly oxygenated blood towards the heart
- End artery: The artery which have no precapillary anastomosis
- Vasa vasorum: A vessel supplying a vessel is known as vasa vasorum. It is present in tunica adventitia coat of large vessels. E.g. coronary arteries.
Veins are the channels that carry blood toward the heart. Poorly oxygenated blood is carried by all veins in the body except pulmonary veins which carries oxygenated blood. It possess thin muscle wall and numerous than the arteries. Veins are elliptical in collapsed state and circular in filling state. Venous valves are numerous in distal part of lower extremity and the number of valves decreases proximally. There is no valve in superior and inferior vena cava. It is formed from capillary tissue fluid (micromolecular in nature). Blood vessels are arranged in following pattern. Arteries have supply function, capillary (terminal vascular bed) have exchange function and veins have reservoir function. In human body four types of venous system are present: (1) caval system, (2) portal venous system, (3) azygos venous system, and (4) paravertebral veins.
Differences between artery and vein have been given in Table 1.6.
Apart from artery and vein, there exist another channel in our body, i.e. lymphatic system. Lymphatic system is accessory to venous system. It also drains tissue fluid from the tissue spaces like veins, but the difference is that it carries protein and fat macromolecules from tissue spaces. The veins carry micromolecular substance from tissue space (Fig. 1.20). Lymphatic tissue is essential for immunological defense of the body from bacteria and viruses. Lymphatic tissue starts developing in the 5th week of intrauterine life.
Lymph is the name given to the tissue fluid, once it has entered a lymphatic vessel. Composition of lymph varies from one part of body to another. Before lymph is drained into the bloodstream, it passes at least one lymph node (small masses of lymphatic tissue), sometimes several.
The lymph vessels have numerous valves. The lymph vessels which carry lymph toward the lymph node is known as afferent vessel, and that of which carries lymph away from lymph node is known as efferent vessel. The lymph reaches the bloodstream at the root of the neck by two large lymph vessels called right lymphatic duct and thoracic duct (Fig. 1.21).
The thoracic duct (45 cm long) begins in the abdomen from a sac; cysterna chyli, and enters the thorax through an opening (aortic opening) of diaphragm. It ascends through thorax, lies in front of 7th thoracic vertebrae. At the level of T4 and T5 it bends toward left, lies between aorta on the left-hand side and azygos vein on the right-hand side in the posterior mediastinum behind the esophagus. It then ascends into neck and drains into the angle, formed by left internal jugular and left subclavian vein. From thoracic duct lymph is pumped into venous system during inspiration. The rate of flow of lymph is indirectly proportional to the depth of inspiration. Most of the lymph flow of the body is due to contraction of skeletal muscle like veins.
The right lymphatic duct drains lymph from the body's right upper quadrant (right side of head and neck, right upper limb and right half of thorax). The thoracic duct drains lymph from remainder of the body (Fig. 1.22).
Lymph formation is directly proportional to arterial flow and 40% of lymph is formed within skeletal muscle. In the abdomen and pelvis highest number of lymph node is present.
The central nervous system, the eyeball; the internal ear, the epidermis of skin, cartilage and bone are devoid of lymphatic vessels.
- Lymphangitis: It is the inflammation of lymph vessel. When lymph vessels are severely inflamed, the vasa vasorum (vessel supplying a vessel) become congested with blood. As a result the pathway of the associated lymphatics becomes visible through skin as red line and painful to touch.
- Lymphadenitis: It is the inflammation of lymph node. These two phenomena may occur when the lymphatic system is involved in the spread of cancer cell.
- Lymphedema: The accumulation of lymph in tissue space. It occurs when lymph is not drained from an area of the body (Fig. 1.23). It is seen in coastal region of Odisha.
- Lymphomas: These are the tumor of lymph glands and are classified as Hodgkin's and non-Hodgkin's lymphomas.