Diabetic Foot Wound Assessment
What to Expect During Your Foot Ulcer Examination
If you have diabetes, you cannot assume that a foot wound is a diabetic foot ulcer without ruling out other possible causes such as venous ulcers (caused by improperly functioning venous valves, typically in the legs), ischemic ulcers (caused by arterial insufficiency), vasculitic ulcers (caused by inflammatory damage to blood vessels), or malignancies.
A physician must first complete a thorough examination and documentation of findings to properly diagnose a foot wound and ensure that the proper treatment plan is implemented. A foot ulcer examination should include an assessment of neurological status, vascular status, and evaluation of the actual wound, including essential information such as wound size, depth, shape, location, base, and border, along with signs of infection and deterioration.
As a proven method of testing for the presence or absence of “protective sensation,” neurological status can be checked using 10-gram monofilaments. A patient is considered to have lost their protective sensation once they cannot feel a 10-gram monofilament pressed against their skin – placing them at higher risk for injuring their foot without feeling it. However, a clinician must also test for vibratory sensation using a 128-Hz tuning fork because some high risk patients who have lost their vibratory perception can still feel a monofilament. Both of these sensory tests can be easily performed in an office setting. But there are also more in-depth analyses best performed in a neurological setting, including the use of a vibrometer, (a device that more accurately measures vibratory sensation), nerve conduction studies, assessing one’s temperature sense, and checking position sense and balance.
A vascular assessment is notably useful when evaluating diabetic ulcers. This involves checking pedal pulses, the dorsalis pedis on the dorsum of the foot, and the posterior tibial pulse behind the medial malleolus. Any patient with a non-palpable pedal pulse should seek further testing at a noninvasive vascular laboratory. While there, the patient’s capillary filling time must be determined by pressing on the toe until the skin blanches and then timing the skin as color is restored. A prolonged capillary filling time is anything greater than five seconds.
