◊ Muscles Affections ◊
AFFECTIONS OF MUSCLES
Muscle is a tissue composed of bundles of elongated cells capable of contraction and relaxation to produce movement in an organ and it gives the body its general shape. It is called striated because it appears striped, in alternating bands of light and dark, when viewed under a microscope, and animals have conscious control over most of their striate muscles.
The normal anatomy and histology of the muscle revealed that its fibers, which are of elastic nature, run parallel to the long axis of the muscle with which the blood and nerve supply pass in the same direction. The muscle is an organ rich in blood supply and regenerates well but the regenerated tissue is usually of fibrous nature that has lesser elasticity than the original muscular tissue. The main function of the muscle is motion accordingly it is usually in a state of more or less contraction and its origin and insertion is usually tendon or ligament. Viable muscle contracts and bleeds when injured but due to its high contents of glycogen, it poorly hold suture material.
It is concluded that suturing of muscle require induction of muscular relaxation, and severing of muscle during surgery should be made parallel to the fibers as possible (grid technique) to minimize bleeding and fibrous tissue formation.
I-OPEN WOUNDS OF MUSCLES
It should be treated either it is recent or old wound, although the muscle usually unable to hold the suture material well.
II-RUPTURE OF MUSCLES
Muscle frequently subjected to ruptures that are either partial or complete, or at its middle or near insertion. Generally, rupture of muscle is not as common as that of tendons.
1-Severe contraction of the muscle
2-It occurs in the relaxed muscle by severe contraction of the corresponding muscle
1-General symptoms of inflammation or hematoma
2-Lameness if the muscle involved in motion
3-Hernia if the muscle is abdominal one
*Slight rupture heals spontaneously and signs of inflammation and functional disturbance subside
*Severe rupture is incurable as the muscle heals with formation of fibrous tissue that interferes with the normal function of the muscle
1-Applying rest to the animal
2-Applying the usual remedies of traumatic inflammation
It ensues as a result of
1-Disuse of muscle (during fracture)
2-Paralysis (injury of nerve)
4-Senility or poor nutrition (usually generalized)
The size of the affected muscle is smaller than that of the healthy side, and when the affection is bilateral, the size of the affected muscle will be smaller than that of another healthy animal of the same size.
1-Remove the cause
2-Massage of the muscle to preserve its tone and stimulate blood supply
3-Application of counter irritants for stimulate nerve
4-Exercise for stimulation of the muscle
5-Administration of nerve tonics
IV-MUSCULAR SPASM (CRAMP)
A muscle spasm or cramp is an involuntary contraction of muscle that occurs suddenly usually resolves quickly, and is often painful.
Muscular spasms are either;
1-Tonic (continuous) like tetanus
Tonic spasm of the muscle may ensue as a result of severe muscular exertion and it may be related to irritation of the nerve endings by the product of the fatigued muscle.
2-Colonic (intermittent) like strychnine toxicity
Colonic spasm is an intermittent form of spasm like that observed with strychnine toxicity
The symptoms of muscle spasm depend upon the muscle involved and the circumstances leading up to the spasm. Skeletal muscle spasm usually involves muscles that perform excessive work. There is acute onset of pain as the muscle contracts. A bulging muscle may be seen or felt rigid underneath the skin where the muscle is located. Most often, the spasm resolves spontaneously after a few seconds though it may last many minutes or longer. Usually, the patient will feel the need to stretch the muscle involved, thus relieving the spasm and resolving the episode. Affected hind limbs are directed caudally like patellar luxation.
Applying cold douches and massage
It ensues as a result of trauma or bacterial infection
i-Simple myositis: -
It ensues after minor muscular injuries without breaking the skin like trauma or injection of irritant drugs. The affected muscle is hard, thick and painful, and may contain hematoma or sterile abscess, and lameness appears if the limb is involved. During healing, the formed exudates are resorbed, and the damaged fibers regenerate.
4-Treatment of large abscess or hematoma
ii-Bacterial myositis: -
It ensues due to extension of bacterial infection from phlegmon or cellulites or directly invade muscle with contaminated penetrating object (the skin is opened). The most common cause of that type of myositis is clostridia.
Affected area is painful on palpation, with firm swelling of variable size. Animal may show systemic reaction according to the causative organism, like fever. Lameness is clear when one or more limbs are affected.
- Local treatment of infected area
- Systemic treatment
B-Rheumatic Myositis (rheumatism)
It is observed in winter in neck, back, and limbs, and the affected muscles are tense, contracted, and painful, and pain is recurrent.
- Anti-inflammatory (steroidal or non-steroidal)
- Local antiphlogistine
A-Chronic Fibrous Myositis
It is an extension of acute form and it is characterized by reduced signs of pain and lameness
This type was recorded in certain breeds of dog, and characterized by wide opening of the mouth with enlargement of mastication muscles that appears hard in touch, and later on it shows atrophy leading to changes in the shape of the face, but signs of pain or systemic reaction (fever) are usually absent. The eyeball shows bulging and the 3rd eyelid protrudes to cover about 50% of the eye, and finally the cornea becomes dry and ulcerated that may lead to blindness.
The affection is recurrent with weeks of interval during which the animal appears normal but as it reoccur, the disease takes the chronic nature. Examination of blood sample reveals state of eosinophilia.
3-Local treatment of the eye
C-Chronic Myositis Ossificans: -
It occurs after trauma or inflammation of the muscle and characterized by calcification or deposition of calcium slat in the muscle and its connective tissue.
It is mentioned before under the topic tumor
It is mentioned before under the topic nerve affections