Skin Complications in RSDProf dr RJA Goris
Department of Surgery
University Medical Center Nijmegen
Nijmegen 6500 HB, The Netherlands
One of the complications that may occur in RSD of long standing is the appearance of
various skin problems. These problems do occur in some 5% of patients with long-standing RSD, and some may prove very difficult to heal. In this brief overview, I’ll discuss the most frequently occuring skin problems.Dark discolouration of the skin
Initially, I thought this was due to excessive production of menin (skin pigment). But later it became clear that this dark skin actually consists of a thick outer layer of
epidermis, which may peel on occasion. Pic 1Fig 1.Example of severe late RSD with skin discolouration, chronic edema (swelling),
problems with skin and nail care, bruisable skin and some ulceration.
The discoloration occurs as a consequence of disuse of the limb (the outer layers of the skin do not wear off), and/or due to extreme hypersensitivity of the limb, impairing proper skin care. This discoloration is harmless and does not require special treatment. Washing, scrubbing, or eventually a cream with salicylic acid may solve the problem.Abnormal nail growth
Most RSD patients may notice that the nails of the affected extremity may grow faster or slower, and may become harder and brittle.
The nails may show a more pronounced curvature, in the axis of the finger and/or in a transverse direction (above). Technically, physicians refer to this as “hour-glass” nails. Cutting these hard nails in the presence of hyperalgesia may prove to be an ordeal. In the foot, especially the nail of the big toe, this
bending of the nail may cause an “ingrown toe nail.” This may require minor surgery, which is always tricky in a limb with RSD. In mild cases I suggest taking a flat
or triangular file and progressively thinning the middle area of the nail, so that it’s “back”is weakened and the pressure is taken off its sides. Evidently, this filing has
to be repeated regularly. Thin, brittle skin
As a result of tissue atrophy, the skin may become very thin, tight, brittle, and easily bruised (Fig.2). The skin may also take on the appearance of eczema.Fig 2. (scan 1.4)Example of thin, brittle, eczematous skin.Skin ulceration
In worse cases, the skin may break down locally, resulting in slow-healing ulcers next to spots where new ulcers appear (Fig 3,4).Fig 3 (top) and 4 (above)Examples of a extensive ulceration of the skin.Lymphedema
In extreme cases, a persistent severe swelling of the limb may result, possibly due to blockage of the lymphatics (Fig 5). In these cases, deep venous thrombosis has to be excluded. Because compression dressings may cause excruciating pain, they are not a treatment option. The swelling may reside partially with these dressings, but almost invariably recurs after stopping that particular form of treatment.Fig 5.Example of case with severe lymphedema, skin discolouration and ulceration of the leg and foot (the bigtoe is just visible). There also is an extreme equinus position of the ankle joint. This exceptionnal patient finally developped severe infections in the
foot, finally requiring amputation.
In cases with the more severe skin changes (numbers 3to 5), I would suggest comparing the skin temperature with the healthy side. This can be done with an infrared
ear-thermometer. If the skin is substantially colder, measures should be taken to improve the blood circulation to the skin. We usually start with peripheral vasodilator drugs (verapamil, ketanserin etc, in fairly high doses if necessary and possible). If this does not
work or results in too many side effects, a sympathetic block may be considered. In the worst cases, we would admit the patient for treatment with an axillary catheter (upper extremity), or an epidural catheter (lower extremity).
Besides providing for optimal blood circulation in the skin, appropriate treatment of the RSD is mandatory. We therefore use an extensive protocol, including antioxydants. Also a protective, padded, well-aired splint may decrease the number of new skin ulcers.
Specific treatment for the skin changes caused by RSD by dermatologic methods, in my experience, has given little benefit; however, various skin creams may have additional therapeutic value.