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Leg, Ankle and Foot

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In general, pain is the main symptom of disorders of the leg, ankle and foot. It often follows exercise and may be aggravated by exercise. Muscle weakness, neurological deficiency, problems with fitting shoes, instability or stiffness of joints, and difficulties in walking and running are common problems in these disorders.

The causes of problems are usually multifactorial, but most often they arise from biomechanical factors, infections and/or systemic diseases. Foot, knee and leg deformities, bone and/or soft-tissue changes that follow an injury, excessive stress such as repetitive use, instability or stiffness and improper shoes are common causes of these symptoms. Infections may occur in the bony or soft tissues. Diabetes, rheumatic diseases, psoriasis, gout and blood circulation disturbances often lead to such symptoms in the lower limb.

Besides the history, a proper clinical examination is always necessary. Deformities, function disturbances, the blood circulation and the neurological state should be carefully examined. Analysis of gait may be indicated. Plain radiographs, CT, MRI, sonography, ENMG, vascular imaging and blood tests may contribute to the pathological and aetiological diagnosis and treatment.

Principles of treatment . The treatment should always be directed towards eliminating the cause. Except in traumas, the main treatment is usually conservative. The deformity will be, if possible, corrected by proper shoes and/or orthosis. Good ergonomic advice, including correction of wrong walking and running behaviour, is often beneficial. Diminishing of excessive loading, physiotherapy, anti-inflammatory drugs and in rare cases a short immobilization may be indicated. Redesign of work may be indicated.

Surgery may also be recommended in some acute traumas, especially for some persistent symptoms which have not benefited from conservative therapy, but specific medical advice is needed for each case.

Achilles Tendinitis

The disorder is usually due to overuse of the Achilles tendon, which is the strongest tendon in the human organism and is found in the lower leg/ankle. The tendon is exposed to excessive loading, especially in sports, resulting in pathological inflammatory and degenerative changes in the tendon and its surrounding tissues, bursae and paratenon. In severe cases a complete rupture may follow. Predisposing factors are improper shoes, malalignment and deformities of the foot, weakness or stiffness of the calf muscles, running on hard and uneven surfaces and intensive training. Achilles tendinitis occasionally occurs in some rheumatic diseases, after fractures of the crus or foot, in some metabolic diseases and following renal transplantation.

Pain and swelling in the region of the calcaneal tendon, the Achilles tendon, are rather common symptoms, especially in sportsmen. The pain is located in the tendon or its attachment to the calcaneum.

More men than women develop Achilles tendinitis. The symptoms are more frequent in recreational sports than in professional athletics. Running and jumping sports may especially lead to Achilles tendinitis.

The tendon is tender, often nodular, with swelling, and the tendon is fibrotic. Microruptures may be present. A clinical examination can be supported mainly by MRI and ultrasonography (US). MRI and US are superior to CT for demonstration of the region and quality of the soft-tissue changes.

Proper shoes in misalignment, orthotics, and advice in correct biomechanical training may prevent the development of Achilles tendinitis. When symptoms are present a conservative treatment is often successful: prevention of excessive training, proper shoes with heal lifts and shock absorption, physiotherapy, anti-inflammatory drugs, stretching and strengthening of the calf muscles.

Calcaneal Bursitis

Pain behind the heel, usually aggravated by walking, is often caused by a calcaneal bursitis, which frequently is associated with Achilles tendinitis. The disorder may be found in both heels and can occur at any age. In children, calcaneal bursitis is often combined with an exostosis or osteochondritis of the calcaneum.

In most cases improper footwear with narrow and hard back of the shoe is the cause of this disorder. In athletics excessive loading of the heel region, as in running, may provoke Achilles tendinitis and retrocalcaneal bursitis. A deformity of the back of the foot is a predisposing factor. There is usually no infection involved.

Upon examination, the tender heel is thickened and the skin may be red. There is often an inward bending of the hind part of the foot. Especially for differential diagnosis, radiographs are important and may reveal changes in the calcaneum (e.g., Sever’s disease, osteochondral fractures, osteophytes, bone tumours and osteitis). In most cases the history and the clinical examination will be supported by MRI or sonography. A retrocalcaneal bursogram can provide further insight into chronic cases.

The symptoms may subside without any treatment. In mild cases conservative treatment is usually successful. The painful heel should be protected with strapping and proper shoes with soft backs. An orthosis correcting the wrong position of the hind part of the foot may be valuable. A correction of the walking and running behaviour is often successful.

Surgical excision of the bursa and the impinging part of the calcaneum is indicated only when conservative treatment has failed.

Morton’s Metatarsalgia

Metatarsalgia is pain in the forefoot. It may be due to a neuroma of the plantar digital nerve, Morton’s neuroma. The typical pain is in the forefoot, usually radiating in the third and fourth toes, rarely in the second and third toes. The pain occurs on standing or walking at any age but is most frequent in middle-aged women. At rest the pain disappears.

The condition is often connected with flat forefoot and callosities. Compression of the metatarsal heads from side to side and of the space between the metatarsal heads may elicit pain. In plain radiographs the neuroma is not seen but other changes (e.g., bony deformities causing metatarsalgia) may be visible. MRI may reveal the neuroma.

Conservative treatment—proper shoes and pads—to support the anterior arch is often successful.

Tarsal Tunnel Syndrome

Burning pain along the sole of the foot and in all toes which may be due to compression of the posterior tibial nerve within the fibro-osseous tunnel under the flexor retinacle of the ankle, are all symptoms of tarsal tunnel syndrome. There are many conditions leading to compression of the nerve. The most common causes are bone irregularities, ankle fractures or dislocations, local ganglia or tumours, or bad footwear.

There may be loss of feeling in the areas where the medial and lateral plantar nerves lie, weakness and paralysis of foot muscles, especially the toe flexors, a positive Tinel’s sign and tenderness in the region of the nerve course.

A proper clinical examination of the function and the neurological and vascular state is essential. The syndrome may also be diagnosed by electrophysiological tests.

Compartment Syndromes of the Lower Limb

A compartmental syndrome is a result of prolonged high pressure of a closed intrafascial muscle space leading to markedly reduced blood circulation in the tissues. The high intracompartmental pressure is usually due to trauma (crush injuries, fractures and dislocations), but it will also result from overuse, from tumours and from infections. A tight cast may lead to a compartmental syndrome, as may diabetes and blood vessel disorders. The first symptoms are tense swelling, pain and curtailment of function which are not relieved when the leg is elevated, immobilized or treated with common drugs. Later on there will be paresthesia, numbness and paresis. In growing persons, a compartment syndrome may result in growth disturbances and deformities in the affected region.

If a compartment syndrome is suspected, a good clinical examination should be performed including that of the vascular, the neurological and the muscular state, the active and passive mobility of the joint and so on. Measurement of the pressure by multi-stick catheterization of the compartments should be performed. MRI, Doppler investigation and sonography may be helpful in the diagnosis.

Foot and Ankle Region Tenosynovitises

Of many symptoms in the foot, pain following tenosynovitis is rather common, especially in the ankle region and the longitudinal arch. The cause of the synovitis may be deformities of the foot, such as planovalgus, excessive stress, improper shoe fit, or sequelae to fractures and other injuries, rheumatological disorders, diabetes, psoriasis and gout. Synovitis may occur in many tendons, but the Achilles tendon is most often affected. Only rarely does tendinitis involve infection. A medical history and clinical examination are essential in the diagnosis of synovitis. Local pain, tenderness and painful movement are the main symptoms. Plain radiographs that show the bone changes and MRI, especially for changes in the soft tissues, are needed.

Ergonomic advice is needed. Proper shoes, correction of the walking and running habits and prevention of excessive stress situations on the job are usually beneficial. A short period of rest, immobilization in a cast and anti-inflammatory drugs are often indicated.

Hallux Valgus

Hallux valgus consists of extreme deviation of the first joint of the great toe towards the midline of the foot. It is often associated with other foot disorders (varus of the first metatarsal; flat foot, pes planotransversus or planovalgus). Hallux valgus may occur at any age, and it is seen more commonly in women than in men. The condition is in most cases familial, and it is often due to the wearing of improperly fitted shoes, such as ones with high heels and narrow pointed toe boxes.

The metatarsal joint is prominent, the first metatarsal head is enlarged, and there may be a (often inflamed) bursa bunion over the medial aspect of the joint in this condition. The great toe frequently overrides the second toe. The soft tissues of the toe are often changed due to the deformity. The range of extension and flexion of the metatarsophalangeal joint is usually normal, but it may be stiff due to osteoarthritis (hallux rigidus). In the vast majority of cases the hallux valgus is painless and requires no treatment. In some cases, however, hallux valgus causes shoe fitting problems and pain.

The treatment should be individualized according to the age of the patient, the degree of the deformity and the symptoms. Especially with adolescents and cases with mild symptoms, conservative treatment is recommended—proper shoes, insoles, pads to protect the bunion and so on.

Surgery is reserved especially for adult patients with severe shoe-fitting problems and pain, whose symptoms are not relieved by conservative treatment. The surgical procedures are not always successful, and therefore mere cosmetic factors should not be a real indication for surgery; but there is a great range of opinions regarding the usefulness of the approximately 150 different surgical procedures for hallux valgus.

Fascitis Plantaris

The sufferer feels pain under the heel, especially on long standing and walking. The pain radiates frequently to the sole of the foot. Plantar fascitis may occur at any age, but it is most frequent in middle-aged persons. The patients are often obese. It is also a rather common disorder in people who engage in sports. Often the foot has a flattened longitudinal arch.

There is local tenderness especially beneath the calcaneum at the attachment of the plantar fascia. All the fascia may be tender. On x ray a bony spur is seen in the calcaneum in about 50% of the patients, but it is also present in 10 to 15% of symptomless feet.

The causes of fascitis plantaris are not always clear. An infection, particularly gonorrhaea, rheumatoid arthritis and gout may cause the symptoms. Most frequently no specific diseases are connected to the condition. Increased pressure and tension of the fascia may be the main cause of the tenderness. The calcaneal spur may be a result of overusing of the fascia plantaris. It is probably not the primary cause of the calcaneal tenderness, because so many patients with those symptoms have no calcaneal spur and many with calcaneal spur are symptomless.



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