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Appendix A


War Department Technical Bulletin (TB Med 81)
War Department, Washington 25, D. C. >
4 AUGUST1944

1. DEFINITION. a. Trench foot is the term applied to the condition resulting from prolonged exposure of the feet to cold and moisture, usually associated with dependency and immobility of the lower extremities and with constriction of the limbs by shoes or clothing. The condition is closely related to immersion foot and shelter foot. Prolonged standing or long hours spent in an upright or crouching position in cold, wet trenches or foxholes, especially if they have previously become mud-soaked by rain and the weather then changes to frost, and the continual wearing of wet socks and footgear, are the most frequently responsible circumstances leading to the development of the syndrome. The period of exposure varies from several hours to several weeks.
    b. Factors influencing the occurrence and severity of the condition include degree of cold, duration of exposure, and footwear which, although affording some protection during short exposure, causes constriction and is harmful after long exposure. Contributory factors are dependency and immobility which reduce peripheral circulation; body cooling as from wind and inadequate, damp, or wet clothing and footwear, resulting in loss of body heat and production of general vasoconstriction with consequent circulatory stagnation; trauma; and dehydration and nutritional and vitamin deficiency. Men over 40 and youths under 17 appear to be less resistant to the general effects of cold than those of intermediate ages. Racial hypersusceptibility to cold has not been definitely established, but it appears that individuals accustomed to a warm environment do not have the same defenses as those who have been accustomed to colder climates.

2. PATHOGENESIS AND MORBID ANATOMY. a. The essential vascular change during the period of exposure and hypothermia is peripheral vasoconstriction which involves predominantly the arteriolar vessels but may affect even the larger arteries and which results in a decreased blood flow to the part. This is induced both reflexly and as a result of the direct action of cold. The resultant ischemia causes anoxia of the capillaries with consequent increased permeability, exudation, and edema. Existing arterial disease or compression of the part by tight shoes or leggings may accentuate this mechanism. Direct thermal injury to the skin from prolonged exposure to cold may also be a factor as well as the traumata incurred from walking on the damaged feet

    b. Immediately after the part is exposed to warmth, there occurs an intense inflammatory hyperemia with excessive vasodilatation which may be due to several factors, including the release of histamine-like substances resulting from tissue injury by the cold, actual damage to vessels, and nerve injury causing vasomotor paralysis This phase of hyperemia is accompanied by swelling of the tissues and edema. The transudation of fluid may be due either to mechanical factors or, in most instances, to increased permeability of the damaged capillary endothelium. A vicious circle is thus established, in which transudation contributes further to an already existing oxygen deficiency in the involved part. Involvement of peripheral nerves is suggested by paresthesias, dysthesias, anesthesia, and sudomotor disturbances. Meager histological studies have revealed mixed degenerative and regenerative changes in peripheral nerves. The significance of these findings is not


established but local interference with neurogenic control of peripheral blood vessels is probable. The tissues appear edematous and contain perivascular collections of lymphocytes, extravasated blood cells, and some polymorphonuclear leucocytes rather similar to any sterile inflammatory reaction. The exudates are fibrinous and the finer lymphatics may be blocked. The vessels themselves may show intimal thickening and vacuolization of the muscle fibers or more complete disorganization with extending thrombosis in the vessels adjacent to the traumatized area. In the more severe forms, histological studies made during the late stages of the condition, i. e.,several months after exposure, show atrophy and thinning of the epidermis with much fibrosis and deposition of collagen around the nerve endings and blood vessels in the subcutaneous tissues. Fibrous infiltration of the muscles is also evident. This is believed to be the explanation for the late pain, rigidity, and weakness of the feet in this group of patients. The observation that these patients tend to improve spontaneously after 6 to 8 months, the time at which collagen ceases to contract, supports this belief.

3. CLINICAL MANIFESTATIONS. a. Classification. The clinical manifestations are variable. Depending upon the period of exposure and extent of tissue damage, the condition as it appears clinically during the period following admission may be classified according to degree as mild, moderate, and severe. The mild type is characterized by erythema, slight sensory changes, and little or no pitting edema. In addition to these manifestations, there are, in the moderate type, blebs, ecchymotie spots, and definite pitting edema. In the severe forms, these manifestations are more pronounced with evidence of massive extravasations of blood and incipient or actual gangrene.
    b. Signs and symptoms. (1) During onset and period of exposure, there is first an uncomfortable sensation of coldness of the feet, and this is soon followed by numbness. There may be temporary tingling, and mild aching or cramping pain about the arches, ankles, and soles of the feet. In general, discomfort is not pronounced during this period, and the most prominent manifestations are numbness and a heavy wooden sensation of the feet. The patients complain of ataxia, walking is clumsy, and they feel as if they were "walking on blocks of wood." Swelling of the feet may occur after several hours or days but is usually not pronounced at this time. The skin, which is at first red, later becomes pale, "waxy white," "sickly yellow," mottled blue, or purplish. Blisters usually develop at a later stage.
        (2) At the time of admission and after the shoes are removed, the signs and symptoms enumerated above are present and may be more pronounced. The feet are cold and may be anesthetic to pain, touch, and temperature. The peripheral pulses may be absent. The signs and symptoms during this period are considerably influenced from the standpoint of onset, duration, and degree by the method of treatment, as well as by the degree of damage which resulted before treatment was instituted. However, the condition progresses through three more or less distinct stages, each with characteristic signs and symptoms:
            (a) Prehyperemic or ischemic stage. This may last for several hours or more. The feet remain cold, somewhat swollen, discolored, and numb. Areas of purplish discoloration may sometimes be observed particularly in or about the toes. Although in the milder cases there may be hyperesthesia, most cases are characterized by anesthesia of varying extent. In the more severe case, there is fairly extensive "sock anesthesia," and in the less severe forms, these areas involve the toes and extend around the margins of the foot and over its plantar aspect. In some cases in which exposure has been sufficiently prolonged, areas of incipient or even actual gangrene may be already apparent, particularly about the toes. Some patients experience a poorly localized, dull, aching sensation in the feet. The peripheral pulses may remain absent for some hours. As the feet grow warm, swelling increases rapidly, and a severe burning pain begins, marking the onset of the second stage.
          (b)Hyperemic or inflammatory stage. This may last from a few days to a few weeks. Swelling increases rapidly, and the feet become red, hyperemic, hot, and dry. The peripheral pulses are full and bounding. Damage is greatest in the toes, the distal part of the dorsum


of the foot, and the ball of the foot. These parts remain edematous and hot and assume a livid cadaveric appearance. Blebs appear, except in the very mild cases, and may be filled with straw-colored fluid or extravasated blood. Patchy areas of ecchymosis are commonly found over the medial aspect of the first metatarsophalangeal joint, and of the longitudinal metatarsal arch, and over the sides of the foot. The rigid swelling, the redness, and the local warmth of the part indicate an intensive hyperemia. Superimposed damage to the peripheral vessels is suggested by the ulceration and actual gangrene which sometimes involves the more vulnerable parts, particularly the toes. The sensory disturbances are quite characteristic and may begin at once or be delayed for several days to a week. The initial anesthesia and hypesthesia are replaced by intense paresthesia. This has been described as an intense burning pain over the surface of the entire foot which seems to be relieved by cold and aggravated by heat or even by warmth. It is sometimes followed by intense, intermittent, stabbing, shooting pains beginning in the ankle joint or in the midtarsus and radiating to the tips of the toes. A generalized tingling sensation is often felt in the skin but is overshadowed by the burning pain. The periphery of the foot is usually anesthetic and this merges more proximally into areas of hyperesthesia and paresthesia. As these sensations subside, they gradually recede distally to the toes. The affected parts may ache or throb, and the pains are made worse by warmth and dependency. Anhydrosis or lack of sweating is evident and seems to coincide with sensory loss. The degree of edema varies with the extent of injury and, in the severe cases, may extend as high as the knee. Usually reaching its height by the fourth to sixth day, it gradually subsides to be followed by fine wrinkling of the skin. The red color slowly fades and usually within a week to 10 days may take on a waxy pallor. In the majority of cases, in which the injury has not been great, the skin assumes a normal color after some exfoliation. In a few cases, however, the feet become cold, blue, and sweaty. The subsidence of edema, heat, and redness marks the end of this stage.
   Complications include localized infection, cellulitis, lymphangitis, and septicemia. Phlebothrombosis along the course of the veins of the dorsum of the feet and along the course of the saphenous veins has occurred and may be associated with petechiae in the nearby skin. Rarely transient hematuria and albuminuria, enlargement of the liver, and mild febrile reaction have been observed in cases of immersion foot but have not been reported in trench foot.
        (c) Posthyperemic stage. The clinical manifestations during this stage vary and depend upon the degree of involvement and type of therapy. In the milder cases, the end results are satisfactory, and there is apparently complete recovery. In the more severe cases, there may be recurrence of pain, tingling, and swelling especially on walking, prolonged standing, or exposure to cold. In many of these cases, the transition from the second to the third stage is not sharp but occurs gradually and, during this period, the manifestations may vary from hour to hour or from day to day from those characteristic of the third stage to those characteristic of the second. In a few cases, deep-seated aching pain persists and may be associated with tenderness in the joints, usually the first metatarsophalangeal joint, or may be localized deep in the arch of the foot. This is usually worse at night. In still others, there may be limitation of motion in the joints, muscle weakness and wasting, and difficulty in walking. Some complain of hyperhidrosis of the feet, and anesthesia and paresthesia in the tips of the toes are not uncommon. The late pains, the paresthesias, and rigidity of the part may be due to compression of nerve endings and infiltration of muscle bundles with scar tissue. Hypo calcification or evidence of osteoporosis has been demonstrated in some of the cases and appears on the roentgenogram as diffuse or rounded areas affecting the distal part of the metatarsal bones and the proximal part of the phalanges. Occasionally, the extremities may become excessively sensitive to cold so that Raynaud's phenomenon or simple coldness may persist for hours after return to a warm environment. These sequelae have been observed for months or years after exposure.


4. PROPHYLAXIS. Prophylactic measures are directed toward conserving body heat and avoiding unnecessarily prolonged exposure of the feet to moisture, coldness, and other factors that decrease peripheral circulation.
    a. Loose-fitting waterproof or water-resistant boots with replaceable thick felt innersoles and heavy woolen socks should be worn to provide good insulation as well as ventilation. The shoe-pac (rubber foot-piece, leather top type of footgear) is probably best for this purpose except on rough mountainous terrain. It is important, however, that the shoe-pac fits properly and does not constrict the toes or foot when the innersole and heavy woolen socks are used. If shoes are worn, they should be water-resistant, of relatively soft top construction, and sufficiently large to accommodate heavy woolen socks without constriction.
    b. Every effort should be made to keep the feet dry and, if the socks or innersoles become damp or moist as a result of perspiration or prolonged immersion in wet mud or snow, they should be replaced by dry ones as soon as possible. An extra pair of dry heavy woolen socks should be carried by each soldier and others made available by an exchange service when troops are on duty in wet cold regions for periods longer than several days.
    c. Standing in water or mud-soaked areas should be avoided as much as possible even though waterproof boots are worn. If the trench or foxhole contains water, it should be bailed out, if possible, and stones or branches of a tree placed at the bottom on which to stand.
    d. The shoes should be removed at least once daily and the feet cleansed and dried. Innersoles and socks should be well dried before being replaced.
    e. Cramped positions, prolonged immobility, and dependency of the extremities should be avoided. Frequent exercises and temporary elevation of the feet are desirable. If this is impractical, exercise of the toes and ankles within the shoes and elevation of the feet should be done as frequently as possible.
    f. The upper part of the body should be kept warm and dry, and exposure to cold winds reduced to a minimum. Gloves should be worn, if possible.
    g. Constriction by tight clothing, shoes, socks, garters, and leggings should be avoided.
    h. Nutrition should be maintained at as high a level as circumstances permit. Whiskey and other alcoholic beverages should be avoided.
    i. Whenever feasible, the feet should be inspected at least once weekly and injuries or infections properly treated.
    j. Whenever circumstances permit, in cold wet weather, troops should be relieved from front-line action after several days exposure.
    k. Unit commanders should be cognizant of the factors concerned in the causation and prevention of trench foot and of the importance of foot discipline and, in accordance with section IV, War Department Circular No. 312, 1944, are held responsible for the diligent application of the protective measures.

5. TREATMENT. The principles of treatment consist essentially of rest, avoidance of local trauma and infection, elevation of the feet to promote drainage of edema fluid, and reduction of metabolism in the affected part. The rationale of treatment is to reduce the metabolic demands of the part until edema subsides, extravasated blood is absorbed, and vasomotor tone is reestablished. Under these conditions, rapid tissue repair is favored. During the recovery stage, the reactive hyperemia, if too intense and if induced too rapidly, can be not only painful but also harmful. Therefore, rapid warming should be avoided.
    a. Initial or einergency treatment. (1) As soon as the symptoms of trench foot appear, the patient should be sent to the hospital. He should be carried and not permitted to walk on damaged feet.
        (2) Wet clothing should be removed and the patient wrapped in warm blankets leaving the involved extremities exposed to the air in a moderately cool room.
        (3) The involved extremities should be handled very gently. The limbs should not be rubbed or massaged. If necessary, the feet may be cleansed carefully with plain white soap and water, dried, and then allowed to remain exposed, and elevated on pillows. While


it is desirable to warm the patient, the feet should always be kept cool by exposure to the room air.
        (4) Strict asepsis must be maintained to avoid infection which may readily develop and rapidly spread in the damaged tissue of the feet. If sulfonamide drugs are available, they may be administered orally until the danger of spreading infection is past.
        (5) Protection against pressure necrosis especially in the region of the heel is desirable and may be accomplished by frequent turning, by doughnut dressings, or by supporting the back of the legs down to the ankles on a pillow.
        (6) During evacuation to the hospital, loose covering of the feet with sterile or, at least, clean towels or sheet is desirable in order to protect against bacterial contamination.       b. Definitive treatment. The same principles which underlie the initial treatment measures (that is, conservation of body heat and avoidance of trauma, infection, and heat to the involved part) are continued in the definitive treatment.
        (1) Patients should be kept in bed, with the affected parts on a horizontal level with or elevated on pillows only slightly above heart level, and protected from external pressure either by complete exposure or by means of a cradle. Elevation of the extremities should be done only if there is evidence of inadequate circulation, that is, incipient gangrene, otherwise they should be maintained on a horizontal level. The period of bed rest is determined by the degree and rate of subsidence of edema.
        (2) Massage or rubbing of any sort in the early stages must be avoided, and the part should be handled as little and as gently as possible. All antiseptics and ointments should be avoided, and blisters ordinarily should not be disturbed.
        (3) Although the feet should remain exposed to the moderately cool room-air (65 F. to 70 F.), the body should be kept warm by means of blankets.
        (4) In the early prehyperemic or ischemic stage when vasospasm is still evident and persists for longer than 6 hours, whiskey in 1-ounce doses may be administered for its vasodilating effect. Sympathetic block, using 1 percent procaine hydrochloride solution, may also be done for this purpose. These measures are not indicated after the hyperemic stage begins and should be discontinued.
        (5) Maintenance of minimal tissue metabolism in the affected parts is important especially during the hyperemic type and may be accomplished by strictly avoiding the application of external heat and, if necessary, by actually cooling the limbs, in those cases in which persistent pain indicates the need for such treatment. In instances where the room temperature is not above 70 F., simple exposure of the parts may be sufficient. Cooling may be enhanced by directing the air from an electric fan against the exposed feet. Still greater cooling can be accomplished by spraying cold water from an atomizer through the fan blades. In the more severe cases with intense hyperemia and severe neuritic pains, these measures may be inadequate and greater cooling is required. This may be achieved through the application of ice bags or the use of a special refrigeration cabinet. If ice bags are to be used, sterile pledgets of cotton or gauze are placed between the toes and the whole foot loosely wrapped with sterile cotton batting and covered with a sterile sheet or towel. Carefully dried ice bags are then placed around each foot over the towel and the whole inclosed in an oiled-silk bag, around which, in turn, is wrapped thick layers of cellu-cotton or other equivalent insulating material. As an outer covering, a rubber pillowcase may be used, loosely tied about the upper calf. Ordinarily, it is sufficient to change the ice bags about every 4 hours. At this time, palpation of the toes may be done to make sure that the part is not too severely chilled. Ordinarily, a skin temperature of about 70 F. is optimum whether ice bags or a refrigeration cabinet is used. In cases with extreme hyperemia, more frequent changing will be necessary, but as hyperemia subsides, fewer ice bags will be needed to reduce the temperature of the foot to the required degree. It may be necessary to continue the ice-bag treatment for several days to 2 weeks. Care should be exercised to avoid wetting and maceration of the skin by the ice bags.


        (6) Measures to prevent secondary infection including tetanus should always be instituted. Sulfadiazine by mouth should be used in cases with threatening infection. Blisters ordinarily should not be disturbed but, if opening becomes necessary, this should be done aseptically using a needle. Dressings, except when cooling is done by ice bags, and all local medication should be avoided. Areas of necrosis and ulceration which may subsequently develop should be treated conservatively as long as possible. In patients with gangrene, amputation should be delayed as long as possible and done early only in the presence of superimposed infection.
        (7) A generally nutritious high protein, high vitamin diet should be supplied.
        (8) After the hyperemia and edema have subsided, graduated vascular exercises should be instituted. These consist of: elevating the extremities 1 to 2 minutes at an angle of 30 0 to 50; hanging the extremities over the side of the bed for 2 to 4 minutes during which the patient should flex and extend the toes; and assuming the supine position with the feet in the horizontal position for 2 to 4 minutes. This cycle is to be repeated for periods of 30 minutes, three to four times daily, for at least a week before the patient is allowed out of bed. Gradually, increasing activity should then be urged.
        (9) Physiotherapy, including warm baths, massage, and passive exercises, is of value in the late stages and should he used, especially when the movement of the toes is limited by late fibrosis or edema.
        (10) In cases with intractable edema and pain not controlled by ordinary measures, sympathetic block, using 1 percent procaine hydrochloride solution, compression dressings or an elastic bandage may be cautiously employed even though the value of these measures has not yet been established. Sympathectomy is indicated only in cases in which there is objective evidence of circulatory insufficiency or in which manifestations resembling Raynaud's phenomenon develop and persist months or years after the acute phase of the disease and can be shown to be relieved by "test" sympathetic blocks.

[A. G. 300.5 (27 Jul 44).]

        G. C. MARSHALL,
      Chief of Staff

     J. A. ULIO,
    Major General,
    The Adjutant General.

    Med Corp Off (1).


TB MED 81 (Change 1)
3 OCTOBER 1944

TB MED 81, 4 August 1944, is changed as follows:

*    *    *    *    *    *    *
b. Definitive treatment

*    *    *    *    *    *    *
(1) Patients should be kept in bed, with the affected parts on a horizontal level with or elevated on pillows only slightly above heart level, and protected from external pressure either by complete exposure or by means of a cradle. Elevation of the extremities should be done only if there is no evidence of inadequate circulation, that is, incipient gangrene, otherwise they should be maintained on a horizontal level. The period of bed rest is determined by the degree and rate of subsidence of edema for this form of treatment

*    *     *    *     *     *     *

[A. G. 300.5 (21 Sep 44).]

    Chief of Staff.

    J. A. ULIO,
    Major General,
    The Adjutant General.


Armies (5) ; Corps (5) ; SvC (10) ; Depts (5) ; Del C (5) ; D (55) ; ID 8 (60) (45) ; IB 5 (35), 8 (10) (2) ; IR 5 (6) (5), 8 (40) (30) (20) (15) (10) (5) IBn 3 (1), 4 (1), 5 (2) (1), 6 (2) (1), 7 (3) (1), 10 (7) (6) (3), 11 (2) (1), 17 (3) (2) (1), 18 (2) (1), 19 (2) (1), 44 (3) (2) ; IC 2, 4 (2), 5 (3) (2) (1), 6 (2), 8 (15) (10) (5) (3) (2), 9 (2) (1), 10 (2), 18 (2), 20 (2) (1), 55 (3) (2) ; Cs of Tech Sv (2) ; Army & Sv Boards (2); ROTC (2); Gen & Sp Sv Schs (5); T of Opn (25); Island C (5); Base C (5); Med Tng Ctrs (60); ASTP Units (1); Induc Stas (10) ; SvC Labs (5).
ID 8 (60) : T/O 8-550.
ID 8 (45) : T/O 8-550S.
IB 5 : T/O 5-510S.
IB 8 (10) : T/O 8-650.
IB 8 (2) : T/O 8-520.
IR 5 (6) : T/O 5-251.
III. 5 (5) : T/O 5-21.
IR 8 (40) : T/O 8-560: 8-580.

For explanation of symbol, see FM 21-6.
IR 8 (30) : T/O 8-581.
IR 8 (20) : T/O 8-590.
IR 8 (15) : T/O 8-510.
IR 8 (10) : T/O 8-750; 8-760.
IR 8 (5) : T/O 8-5725; 8-780; 8-790.
IBn 3 : T/O 3-25.
IBn 4 : T/O 4-45: 4-145; 4-232.
Ibn 5 (2) : T/O 5-535S.
Ibn 5 (1) : T/O 5-55; 5-95; 5-275.
IBn 6 (2) : T/O 6-45.
IBn 6 (1): T/O 6-35; 6-55; 6-65; 6-75:6-95; 6-175; 6-325; 6-355; 6-365; 6-395.
Ibn 7 (3) : T/O 7-95.
Ibn 7 (1) : T/O 7-85.
Ibn 10 (7) : T/O 10-95.
Ibn 10 (6) : T/O 10-125.
Ibn 10 (3) : T/O 10-175.
Ibn 11 (2) : T/O 11-15.
Ibn 11 (1) : T/O 11-25.
IBn 17 (3) : T/O 17-115.
Ibn 17 (2) : T/O 17-15.
Ibn 17 (1) : T/O 17-55; 17-125.

Ibn 18 (2) : T/O 18-35.