John Nebitt M.D.
The Individual Patient Lower Extremity Risk

Ihe goal of this section is to assist medical professionals in classifying the degree of risk diabetic and peripheral vascular disease patients have with regard to future lower extremity problems and specifically to give them advice on how to avoid these complications.

Once a patient's degree of risk is established the patient can be given recommendations regarding: the frequency of specific medical follow-up, footwear, skin and nail care, exercise suggestions and job restrictions.

Patients are divided into five groups ranging from patients at very low risk to those at extreme risk of foot complications.

The basis of this classification is the touch discrimination test as measured by a Semmes Weinstein 5.07 monofilament. This test is designed to determine whether a patient's subjective sensation in their feet is present or absent. This test is very quick and inexpensive to perform. The monofilament is pressed against the skin at several locations on the plantar surface and on an area on the dorsum of the foot until the filament buckles. If the patient cannot perceive this pressure, a loss of protective sensation has occurred.

The following is an outline of how this test should be performed:

  • The sensory exam should be done in a quiet and relaxed setting. The patient must not watch whole the examiner applies the filament.
  • Test the monofilament on the patient's hand so he/she knows what to anticipate.
  • The five (or 10) sites to be tested are indicated on the accompanying screening form and a score of x/5 or x/10 can be given.
  • Apply the monofilament perpendicular to the skin's surface Apply sufficient force to cause the filament to bend or buckle.

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  • The total duration of the approach, skin contact, and departure of the filament should be approximately 1-1/2 seconds.
  • Apply the filament along the perimeter and not on an ulcer site, callus, scar or necrotic tissue. Do not allow the filament to slide across the skin or make repetitive contact to the test site.
  • Press the filament to the skin such that it buckles at one of two times as you say "time one" or "time two". Have patients identify at which time they were touched. Randomize the sequence of applying the filament throughout the examination.

This loss in protective sensation is permanent but the progression of its severity is markedly decreased by enhanced blood sugar control.

Please encourage your physician or diabetic nurse to conduct monofilament protective sensation testing each year as part of your yearly physical exam.

The other factors, which are taken into consideration when determining your degree of risk for diabetic foot problems, include the presence of a significant bony deformity, evidence of reduced blood flow to your feet, and the presence or past history of a foot ulcer, bone infection or amputation.

If your protective sensation is normal in your feet and there is no evidence of a significant foot deformity or peripheral vascular disease and you do not have a past history of foot problems, your risk of immediate foot problems are low. Therefore, wearing of a professionally fitted walking shoe and watching your weight through the adherence to prescribed diet and regular exercise program will markedly diminish your chances of developing foot ulcerative problems.

However, if you have a loss of protective sensation, foot deformity and peripheral arterial disease, or history of foot ulcerations, bone infections or an amputation, your risk of future foot pathology is extremely high. As you will see, such patients require rigorous follow up by their health care professionals, specialized footwear, adherence to the daily foot care techniques as outlined in the previous video clip, and also a modification of their exercise activities and job parameters so that they too can decrease their incidence of foot ulceration.

We will now review each of the five patient types individually and make recommendations regarding follow up with their health care professional, footwear, skin and nail care, and exercise and job restrictions for each patient type along the way.

Risk Criteria and Recommendation for Treatment

Risk Care
Problem List
Follow-up
Footwear
Education
Skin and Nail Care
Exercise and Job Restrictions
Low

-Diabetes
-Normal sensation
-+/- minor foot deformity

Yearly
Professionally fitted and accommodative
Footwear education 2-3 months
No restrictions.
Encourage a regular exercise program.
Moderate
-Diabetes
-Loss of protective sensation
-No deformity
6 month
Professionally fitted and accommodative, with total contact insole depending on level of activity
Patient education 6-8 weeks
No restrictions as long as footwear and skin & nail care recommendations are followed.
High
-Diabetes
-Loss of protective sensation
-Foot deformity with callous formation
2-4 month
Professionally fitted and accommodative, with custom-molded foot orthosis
Patient education 6-8 weeks
Emphasis on non-weight bearing activities such as swimming, biking, short walks (20 min. 2-3 times per day), weights and rowing.
Very High
-Diabetes
-Loss of protective sensation
-Foot deformity
-History of ulceration and peripheral vascular disease
1-2 month
+/- custom footwear to accommodate the foot deformity
Patient education 6 weeks
Gait retraining to take shorter steps. Patients who are required to be on their feet for long preiods to perform the duties of their present job will need vocational counselling to assist with a career change.
Extreme
- Presence of an open wound or infection
Once a week as determined by the severity of the problem and the presence of other medical problems.
Special footwear with total contact inserts. Air Cast walking braces or total contact casting will be required to offload the foot wound site
All the prescribed therapeutic measures must be reviewed with the patient and their caregivers during each follow up visit
Still must be attended to every 6 weeks so that other problems do not occur.
Walking must be kept to a minimum until the foot wound has almost healed.

It must be emphasized that:

A) You must not do any weight-bearing exercise when you have open sores on your feet.

B) For peripheral arterial disease patients

  1. The signs of decreased blood flow to one's feet. This includes the presence of thickened, brittle nails, forefoot discoloration or rubor, shininess to the skin over the top of the foot and loss of hair from the toes and top of the foot skin.
  2. Just walking as a form of exercise is not recommended. Instead enjoy a variety of exercises such as biking, swimming, lightweights, rowing and short (15-20 minute) brisk walks and do a different activity each day.
  3. Particular attention must be given to your feet when you notice an increase in foot, ankle or leg swelling since as this occurs, there is increased pressure to your skin caused by now ill-fitting walking shoes and in fact there is also a decrease in blood supply to the skin itself if the swelling is allowed to progress. Therefore, it is essential that you seek immediate medical attention for progressive foot swelling.
  4. When walking, it is important that you try to walk through your (intermittent claudication) calf crampy pain as best as you can. By trying to walk even after your calf muscles start to arch, you are accelerating the development of collateral circulation in your legs to your feet. Do the best that you can but don't hurt yourself. Stop, rest and then try walking at a comfortable pace a bit further the next time.
  5. Peripheral vascular patients must be aware of the significance of night pain especially when it occurs in your first toe. This pain is ischemic in nature secondary to the fact that in bed your foot is now in an elevated position and you are losing the benefit of gravity to assist in the delivery of blood to that digit.
    You must report this to your doctor as the blood flow to your feet is now at a critically low level and peripheral vascular testing is required if it has not already been done.

C) If your feet require specially designed shoes, ask your insurance plan or HMO about coverage for the cost of the shoes. Medicare will cover foot exams and may cover special (orthotic) shoes or shoe inserts

© COPYRIGHT 2008 JOHN NESBITT M.D.