Common Foot Problems
Disabilities of the foot are commonly caused by poorly fitting shoes. Fashion, vanity, and eye appeal, rather than function and physiology of the foot, are the determining factors in the design of footwear. Ill-fitting shoes distort normal anatomy while in-ducing deformity and pain.
Several systemic diseases affect the feet. Patients with diabetes are prone to develop corns and peripheral neuropathies with di-minishing sensation, leading to ulcers at pressure points of the foot. Patients with peripheral vascular disease and arteriosclerosis complain of burning and itching feet resulting in scratching and skin breakdown. Foot deformities may occur with rheumatoid arthritis. Dermatology problems commonly affect the feet in the form of fungal infections and plantar warts.
The discomforts of foot strain are treated with rest, elevation, physiotherapy, supportive strappings, and orthotic devices. The patient must inspect the foot and skin under pads and orthotic devices for pressure and skin breakdown daily. If a “window” is cut into shoes to relieve pressure over a bony deformity, the skin must be monitored daily for breakdown from pressure exerted at the “window” area. Active foot exercises promote the circulation and help strengthen the feet. Walking in properly fitting shoes is considered the ideal exercise.
Plantar fasciitis, an inflammation of the foot-supporting fascia, presents as an acute onset of heel pain experienced with the first steps in the morning. The pain is localized to the anterior medial aspect of the heel and diminishes with gentle stretching of the foot and Achilles tendon. Management includes stretching exer-cises, wearing shoes with support and cushioning to relieve pain, orthotic devices (eg, heel cups, arch supports), and NSAIDs. Un-resolved plantar fasciitis may progress to fascial tears at the heel and eventual development of heel spurs.
A corn is an area of hyperkeratosis (overgrowth of a horny layer of epidermis) produced by internal pressure (the underlying bone is prominent because of congenital or acquired abnormality, commonly arthritis) or external pressure (ill-fitting shoes). The fifth toe is most frequently involved, but any toe may be involved.
Corns are treated by soaking and scraping off the horny layer by a podiatrist, by application of a protective shield or pad, or by surgical modification of the underlying offending osseous struc-ture. Soft corns are located between the toes and are kept soft by moisture. Treatment consists of drying the affected spaces and separating the affected toes with lamb’s wool or gauze. A wider shoe may be helpful. Usually, a podiatrist is needed to treat the underlying cause.
A callus is a discretely thickened area of the skin that has been ex-posed to persistent pressure or friction. Faulty foot mechanics usually precede the formation of a callus. Treatment consists of eliminating the underlying causes and having the callus treated by a podiatrist if it is painful. A keratolytic ointment may be ap-plied and a thin plastic cup worn over the heel if the callus is on this area. Felt padding with adhesive backing is also used to pre-vent and relieve pressure. Orthotic devices can be made to remove the pressure from bony protuberances, or the protuberance may be excised.
An ingrown toenail (onychocryptosis) is a condition in which the free edge of a nail plate penetrates the surrounding skin, either laterally or anteriorly. A secondary infection or granulation tissue may develop. This painful condition is caused by improper self-treatment, external pressure (tight shoes or stockings), internal pressure (deformed toes, growth under the nail), trauma, or in-fection. Trimming the nails properly (clipping them straight across and filing the corners consistent with the contour of the toe) can prevent this problem. Active treatment consists of wash-ing the foot twice a day, followed by the application of a local an-tibiotic ointment, and relieving the pain by decreasing the pressure of the nail plate on the surrounding soft tissue. Warm, wet soaks help to drain an infection. A toenail may need to be ex-cised by the podiatrist if there is severe infection.
Hammer toe is a flexion deformity of the interphalangeal joint, which may involve several toes (Fig. 68-6). The condition is usu-ally an acquired deformity.
Tight socks or shoes may push an overlying toe back into the line of the other toes. The toes usu-ally are pulled upward, forcing the metatarsal joints (ball of the foot) downward. Corns develop on top of the toes, and tender calluses develop under the metatarsal area. The treatment consists of conservative measures: wearing open-toed sandals or shoes that conform to the shape of the foot, carrying out manipulative ex-ercises, and protecting the protruding joints with pads. Surgical correction (osteotomy) is necessary for an established deformity.
Hallux valgus (commonly called a bunion) is a deformity in which the great toe deviates laterally (see Fig. 68-6). Associated with this is a marked prominence of the medial aspect of the first metatarsal–phalangeal joint. There is also osseous enlargement (exostosis) of the medial side of the first metatarsal head, over which a bursa may form (secondary to pressure and inflamma-tion). Acute bursitis symptoms include a reddened area, edema, and tenderness.
Factors contributing to bunion formation include heredity, ill-fitting shoes, and gradual lengthening and widening of the foot associated with aging. Osteoarthritis is frequently associatedwith hallux valgus. Treatment depends on the patient’s age, the degree of deformity, and the severity of symptoms. If a bunion deformity is uncomplicated, wearing a shoe that conforms to the shape of the foot or that is molded to the foot to prevent pres-sure on the protruding portions may be all the treatment that is needed. Corticosteroid injections control acute inflammation. Surgical removal of the bunion (exostosis) and osteotomies to re-align the toe may be required to improve function and appear-ance. Complications related to bunionectomy include limited range of motion, paresthesias, tendon injury, and recurrence of deformity.
Postoperatively, the patient may have intense throbbing pain at the operative site, requiring liberal doses of analgesic medica-tion. The foot is elevated to the level of the heart to decrease edema and pain. The neurovascular status of the toes is assessed. The duration of immobility and initiation of ambulation depend on the procedure used. Toe flexion and extension exercises are initiated to facilitate walking. Shoes that fit the shape and size of the foot are recommended.
Pes cavus (clawfoot) refers to a foot with an abnormally high arch and a fixed equinus deformity of the forefoot (see Fig. 68-6). The shortening of the foot and increased pressure produce calluses on the metatarsal area and on the dorsum (bottom) of the foot. Charcot-Marie-Tooth disease (a peripheral neuromuscular dis-ease associated with a familial degenerative disorder), diabetes mellitus, and tertiary syphilis are common causes of pes cavus. Exercises are prescribed to manipulate the forefoot into dorsi-flexion and relax the toes. Bracing to protect the foot may be used. In severe cases, arthrodesis (fusion) is performed to reshape and stabilize the foot.
Morton’s neuroma (plantar digital neuroma, neurofibroma) is a swelling of the third (lateral) branch of the median plantar nerve (see Fig. 68-6). The third digital nerve, which is located in the third intermetatarsal (web) space, is most commonly involved. Microscopically, digital artery changes cause an ischemia of the nerve.
The result is a throbbing, burning pain in the foot that is usu-ally relieved when the patient rests. Conservative treatment con-sists of inserting innersoles and metatarsal pads designed to spread the metatarsal heads and balance the foot posture. Local injec-tions of hydrocortisone and a local anesthetic may provide relief. If these fail, surgical excision of the neuroma is necessary. Pain re-lief and loss of sensation are immediate and permanent.
Flatfoot (pes planus) is a common disorder in which the longitu-dinal arch of the foot is diminished. It may be caused by congen-ital abnormalities or associated with bone or ligament injury, muscle and posture imbalances, excessive weight, muscle fatigue, poorly fitting shoes, or arthritis. Symptoms include a burning sensation, fatigue, clumsy gait, edema, and pain.
Exercises to strengthen the muscles and to improve posture and walking habits are helpful. A number of foot orthoses are available to give the foot additional support. Orthopedic surgeons and podiatrists treat severe flatfoot problems.