Surgical diseases of muscles and tendons

In many conditions involving muscles and/or tendons, surgery may be the treatment of choice. Various pathological states occur.

Congenital Deformities

Congenital deformities of this system are un­common. Some muscles, however, may be ab­sent since birth. Such an absence may occur on one side or both, and disability may be present if the missing muscle is a major one. Some mus­cles are so inconsistent from person to person that their absence is not considered abnormal. Underdevelopment of muscles at the time of birth can occur, but more often such is acquired rather than congenital.

Inflammations of muscles and tendons

Inflammation of muscle is known as myositis. It may be acute or chronic.

The acute form may stem from injury with an open wound wherein germs enter or may follow a bruise of the muscle; in the latter instance the germs spread from an area of adjacent infection, or are carried to the area by the blood stream to survive on the stagnant blood in the bruise. Fol­lowing the repair of injured muscle, prophylaxis against myositis is essential. In the early stages treatment is medical, but should it progress to abscess formation surgical drainage is necessary.

The chronic form of myositis may follow the acute stage or may be associated with other chronic infections. As the disease progresses, there occurs an excess of fibrous tissue around the muscle fibers so that the muscle becomes harder and loses its contractility and elasticity. This is called fibrositis. Chronic myositis may be nonspecific or may be caused by a specific type of germ such as tuberculosis, syphilis, or fungus. Most are treated by medical means.

The term myositis has also been vaguely ap­plied to such conditions as “stiff neck,” “lum­bago,” “muscular rheumatism,” and “muscular aches” associated with acute infections.

Inflammation of a tendon is called tendonitis, but most often it is an infection of the covering around a tendon, the tendon sheath, which is known as tenosynovitis. The infection usually starts by a penetration of the skin and occurs most often in the hand. The infection spreads rapidly up the sheath and may extend into the fascial spaces of the hand. Treatment is by medi­cation, heat, and rest of the part. Frequently sur­gical drainage of the involved space or spaces is necessary.

Injuries of muscles and tendons

Injuries of the muscles and tendons are com­mon. They are often associated with other in­juries.

Muscle contusion is a bruise of the structure by the blunt blows of falls, kicks, bites, etc. There is bleeding within the muscle fibers to vari­ous degrees. Treatment consists of immobiliza­tion and relaxation of the affected part until the blood has been re-absorbed. Compression dress­ings may be of value. Later physical therapy and graduated exercises may be employed. Myositis is an impending complication.

Open injuries of muscles are associated with disruptions of skin and overlying parts. Such oc­curs by an incised wound, laceration, or pene­trating wound. These demand operative repair as soon as practical. Debridement for removal of foreign bodies and destroyed muscle is followed by myorrhaphy. In some cases a drain is left in placc. The result is dependent on the extent of the injury, the presence or development of infec­tion, and the amount of functional disturbance. Shallow wounds, punctures, and penetrations heal readily unless foreign substances have been car­ried into the wound or infection develops. The end result of infection or unrepaired muscle is the formation of scar (cicatrix) which impairs function of the muscle; if such should result, myoplasty may be necessary. Immobilization and later physical therapy and exercises are often beneficial.

Rupture of muscle is a tearing apart of the fibers within a muscle by sudden and forceful pull or jerk. The involved muscle is pulled apart and actually gapes; the intervening space be­comes filled with blood. Pain may be pronounced, especially with further use. Certain muscles are more prone to rupture, and definite occupational propensities are apparent: the shoulder muscles are often affected in pitchers and lifters, the thigh muscles in horseback riders, the calf muscles in dancers and sprinters, the thumb muscles in drummers, the neck muscles in load carriers, the arm muscles in tennis players, and the back mus­cles in almost anyone. Rupture of a muscle may be partial or complete, the former predominating. When there is complete tearing apart of a muscle, surgical repair is usually necessary, preferably early. Partial ruptures are treated by immobiliza­tion in the relaxed position, with subsequent phys­ical therapy and exercises. In minor ruptures the small hemorrhages are absorbed with complete recovery, but in extensive ruptures scar tissue may result to hinder function.

Muscle strain, or “sprain,” has been suggested as a separate muscle disease entity. This is mani­fested in muscles which have not been used over long periods of time but suddenly have been called back into action. Such may occur in the occasional athlete. The unconditioned muscles are easily fatigued and minute pinpoint hemor­rhages occur throughout their fibers. Muscle spasms or “charley-horses” and aching muscles develop. Recovery is spontaneous, but rest be­fore resuming activity may be required.

Muscular hernia is the bulging of a portion of a muscle through an abnormal opening in the fascia which invests it. The condition is rare and usually of gradual onset. Through injury there occurs a small rent or tear in the fascia which gradually enlarges. There is noted a bulge in the area, most commonly over an extremity, which is tender and painful. This condition requires sur­gical intervention according to the symptoms; if pain or disability is severe, operation to repair the fascial defect is warranted. The procedure may necessitate removal of part of the bulging muscle (partial myectomy). Again postoperative immobilization and physical therapy may be nec­essary.

Severed tendon frequently occurs in associa­tion with lacerating injuries, most commonly in the hand. One or several tendons may be involved and other vital tissues such as nerves and blood vessels simultaneously severed. The cut in the tendon may partially or completely sever the ten­don. When it is partial, the loss of motion may be minimal but usually requires repair at the time of the laceration repair. Tendons which have been completely severed preclude the muscle from performing its function. The muscle con­tracts but effects no movement since it has been detached from the part it causes to move. Ten­dons will heal together if their ends are in con­tact with each other. However, in almost all instances the fragments are separated by the pull of muscular contraction and muscle elas­ticity. With an intervening space they will not heal and function is forever lost.

Treatment is surgical, and is best accomplished early. The operation entails reconstruction of all the injured tissues to their normal anatomy. The tendon ends are sutured together. Healing is rela­tively slow, and postoperatively splints and casts for immobilization are employed. The part is placed in the position which allows the least tension on the repaired tendon. After healing is complete, or in the later stages of healing, physi­cal therapy and exercises may expedite rehabili­tation.

When segments of tendons have been lost, ten­don transplants may be necessary. In the case where a lacerated tendon has been overlooked, or concurrent injury has obviated early repair, late repair by elective operation may be per­formed. In this instance there is usually scar for­mation in the area which makes the procedure somewhat more extensive. The same postopera­tive devices and care are utilized as with imme­diate repair. In all tendon injuries and operations diligent care to avoid infection is paramount.

Tumors of muscles and tendons

Tumors of the muscles and tendons are for­tunately rare and usually benign. The majority of muscle tumors grow from the supporting tis­sues within the muscles rather than from the muscle fibers themselves. Therefore, such tu­mors as lipoma (fat tumor) and angioma (ves­sel tumor) and fibroma (fibrous tumor) may be encountered developing within the muscle. Muscle tumors may also be secondary spread from malignancy of other tissues, either by direct spread or by metastases. In essence, muscle and tendon tumors may be benign or malignant, primary or secondary.

Benign tumors which cause symptoms should be removed, since progressive enlargement may compress and damage the muscle fibers. Malig­nant tumors demand the removal of an entire muscle, or groups of muscles, with adequate excision of surrounding parts to assure that no cancer cells are left. Amputation of a limb is occasionally necessary. X-ray therapy may be a useful adjunct.

Ganglion is a benign cystic tumor which oc­curs in relationship with tendons, tendon sheaths, and joint capsules. They may be singular or mul­tiple. The exact cause is not understood, but previous injury is no doubt a factor. These thin-walled globular sacs of clear gelatinous fluid develop in and around tendons or as an extension of a joint capsule—a sort of hernia­tion of the joint capsule. They occur most com­monly in the hand and wrist, usually over the back surface. However, they may be found in almost any area. They may produce symptoms of pain and weakness.

Many forms of treatment have been used. Very rarely, breaking the cyst by smartly striking the area with a book to disperse its fluid out into the tissue for absorption will be successful, but most recur. Needling to draw off the fluid is of no avail, for it promptly recollects. Injections of irritating solutions into a ganglion are useless and may be harmful. Removal of a ganglion by surgical excision is the preferred method. The operation entails painstaking dissection down to the sac of fluid, freeing it from all its attach­ments, and closure of the defect. When the gan­glion is in communication with a joint, the at­tachment must be cut and the joint capsule closed. A splint incorporated in the dressing may be needed postoperatively.

Parasites in muscles

Parasites in muscles is an infrequent disease now that meats are subject to sanitary inspec­tion.

Trichinosis, or trichiniasis, is caused by a parasite (Trichina) contained in infested meats, usually pork which has not been thoroughly cooked before eating. The parasites become en­capsulated in the muscles and may cause symp­toms of swelling and pain in the involved mus­cles. In this disease the nodules are removed surgically along with medications to halt the disease.

Cysticercosis is the disease in which the larva of the tapeworm forms cystic nodules in the muscles, rendering them weak and painful. Treatment rests with surgical removal of the nodules in conjunction with medical measures to eradicate the disease.

Hydatid cysts may occur in muscles but more frequently they form in the liver or lungs. This disease is caused by the parasite Echino- coccus. The cysts which form in the muscles are spherical, hard, but painless swellings, which may appear to be a solid tumor. They vary greatly in size, their symptoms varying with the site and size. Treatment is by surgical removal.

Muscle Changes

Muscle changes occur in some normal and abnormal states which affect their size and function.

Atrophy (“no-growth”) of muscles is the shrinking in size of a muscle, arising from many causes. The muscles become flaccid with loss of power as the muscle fibers degenerate. Mus­cles which are not used tend to undergo this process; i.e., from disuse. This change may also occur from injury, prolonged pressure, over­work, or from interference of the circulation or nerve supply. The muscles of a paralyzed limb from any cause shrink in size as the atrophy progresses. Following certain diseases, such as typhoid fever, degeneration and atrophy may ensue. Treatment of muscular atrophy may be by physical therapy, such as electrical muscle stimulations or exercises.

Hypertrophy (over-growth) of muscles is the result of excessive use with an actual in­crease in the amount of muscle fibers. Muscles which are continually employed for strenuous work normally enlarge and become firmer and their strength is increased. The shoulder and arm muscles of the coal shoveler pass through this muscle change. (The muscular heart also will hypertrophy with excessive work or strain.)

Contracture of muscles is a loss of their elasticity and contractility as an increase in the amount of fibrous tissue in the muscle occurs. It results following injuries if a group of mus­cles remains in a state of flexion for some time, or following muscle inflammations or hemor­rhages, or from disease of the nerves supplying the muscles. Treatment rests with physical ther­apy methods; namely, heat, massage, electrical muscle stimulation, and stretching of the mus­cles. Occasionally forceful stretching under anesthesia to break up the adhesions within the muscle is beneficial. In occasional cases opera­tive procedure such as muscle lengthening is indicated.

A specific type of muscle contracture is Volkmann’s contracture (also called ischemic myositis). This occurs following injuries in the vicinity of the elbow wherein the blood sup­ply to the forearm and the hand muscles is im­paired; such may be due to the injury itself or tight casts, bandages, splints, or tourniquets; excessive swelling or bleeding under a cast may produce it.

A large variety of contractures also occurs fol­lowing poliomyelitis.

Dupuytren’s contracture is not actually a muscle contracture but rather a shortening and scarring of the fascia layer within the palm side of the hand. The fingers are drawn into a flexed position and the hand cannot be opened fully. The cause is unknown. The disease is slowly progressive and disabling as the range of finger motion becomes less and less. Treatment is by surgical removal of the palm fascia; skin graft may be necessary. Physical therapy may be beneficial.