Differential Diagnosis in Primary Care
4th Edition

Extremity, Hand, and Foot Deformities
Most deformities of the extremities are due to neurologic or joint diseases, but because there are some exceptions
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to this rule the clinician needs a method for easy recall of all the causes when faced with the complaint. The mnemonic VINDICATE provides the key.
Extremity, hand, and foot deformities
  • V—Vascular disease includes arteriosclerosis, Buerger disease, and Raynaud syndrome, which may lead to gangrene or loss of a foot or digit.
  • I—Inflammatory diseases that deserve special mention include the deformities of poliomyelitis, osteomyelitis, and septic arthritis. Syphilis of the bone causes the saber shin, rarely seen today.
  • N—Neurologic disorders cover the largest group of deformities. The beefy red hand of syringomyelia, the wrist and foot drop of peripheral neuropathy
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    (especially lead poisoning), the claw hand and foot of amyotrophic lateral sclerosis or progressive muscular atrophy, the preacher hand of myotonic dystrophy, and the tight-fisted, flexed, and pronated hand of hemiplegia are the most important ones. Friedreich ataxia causes a hammer toe, and Charcot–Marie–Tooth disease causes a stork leg.
  • D—Degenerative diseases include the degenerative neurologic diseases mentioned above and degenerative osteoarthritis. Deficiency diseases include the bowlegs of rickets. Paget disease causes bowing and hypertrophy of the tibia.
  • I—Intoxication should remind one of the toxic neuropathies such as lead and arsenic, but it also brings to mind the Dupuytren contractures of alcoholic cirrhosis.
  • C—Congenital disorders form another large group. Many of the disorders in this group have been mentioned under neurologic disorders. However, congenital dislocation of the hip, talipes, equinovarus or valgus, and calcaneovarus or valgus should be remembered. These are often signs that a congenital lesion exists elsewhere. Hallux valgus is a frequent deformity of the toes. Pes planus and pes cavus belong in this category, although they are not nearly as significant. The deformities of Marfan syndrome (long fingers with syndactyly), Down syndrome (e.g., short fingers and simian crease), Laurence–Moon–Biedl syndrome, and achondroplasia are mentioned here.
  • A—Autoimmune diseases include the spindle deformities of lupus erythematosus and rheumatoid arthritis; the gangrene, autoamputation, and smooth, swollen hands of scleroderma; and the gangrene of periarteritis nodosa.
  • T—Traumatic lesions need little prompting to recall, but Pott fracture with eversion of the foot and fracture of the neck of the femur that causes eversion of the entire leg are noteworthy. Dislocations of various joints should be easy to spot, but the mallet or baseball finger of ruptured tendons is tricky.
  • E—Endocrine disorders include the large hands of acromegaly, the short fingers of cretinism and pseudohypoparathyroidism, and the swollen hands of myxedema. The accoucheur hand (“pelvic exam hand”) of tetany is appropriate to mention here.
Approach to the Diagnosis
It is usually a simple matter to decide whether the deformity is due to neurologic disease or to joint or bone disease. An x-ray film of the hands or feet may be useful in acromegaly and many congenital disorders. Referral to an orthopedic or neurologic specialist is usually indicated if bone or neurologic involvement is probable. An arthritis workup can be done (see page 284) if joint disease is the cause of the deformity.