Diabetic Foot Ulcers

1. What is a Diabetic Foot Ulcer?

A Diabetic Foot ulcer is a wound (usually on the sole of the foot) that occurs in people with Diabetes.

2. What differentiates Diabetic Foot ulcers from other wounds?

Diabetic Foot ulcers occur because of high pressure in the corresponding area of the foot. This makes them hard to permanently heal by traditional wound healing methods. Though non-surgical methods may be successful in temporarily healing deep wounds there is high chance of   reccurence once the patient resumes normal activities.

3. What are the factors that cause Diabetic Foot ulcers?

The most common cause is a long-standing Neuropathy. Motor Neuropathy causes atrophy of the small muscles of the foot leading to loss of support to the small bones and joints of the foot resulting in deformities. Sensory Neuropathy results in loss of pain sensation which causes these individuals to ignore damage to the foot till it gets complicated. Autonomic Neuropathy causes damage to the nerve fibres that control sweating and blood flow resulting in dry and cracked skin of the feet with poor ability to heal and increasing chances of infection.

4. Do all feet with Diabetic foot ulcers have poor blood supply?

No. Unlike the Western countries, in India most of the people with Diabetic foot ulcers have a good blood supply to the feet.[1] This is a favourable factor to heal wounds and fight infection resulting in higher chances of saving feet provided proper treatment is given at the appropriate time.

5. What are the other major causes of ulceration in people with Diabetes Mellitus?

One of the major problems in people with Diabetes is loss of Elasticity of ligaments resulting in stiff joints (Limited Joint Mobility) which cause reduced shock absorption which in turn causes more tissue loads and injury in the feet.

6. Is there a specific pattern in which Diabetic Foot Ulcers occur and what are the warning signs that one may get an ulcer?

Diabetic Foot ulcers mostly occur in predictable areas of the foot depending on the underlying alteration in the way the foot moves and adapts to loads placed on it. The Great toe is the commonest site of diabetic foot ulcers.

A diabetic foot ulcer is mostly preceded by a callus (Skin thickening) which forms in response to the increased pressure in that area. This callus may be present for a few months before the underlying skin breaks down to form an ulcer which is heralded by a blackish discolouration of the callus. This usually gives enough time for the patient to identify, approach and obtain the advice of a foot care surgeon to prevent complications that may threaten the limb.Rarely a patient may form an abscess as a result of a penetrating injury which results in swelling, redness and fever. These are signs that warrant the patient immediately see a surgeon as an infected foot is a surgical emergency.

7. What are the common areas of ulceration in the Diabetic foot?

The common areas of Diabetic Foot Ulcers are

  • The Great Toe
  • The small toe tips
  • The forefoot (Under the metatarsal heads)
  • The midfoot (Usually associated with a Charcot’s Fracture and midfoot collapse - theRocker Bottom Foot)
  • The Heel
  • The dorsum (Usually secondary to infection).

8. What are the stages of Diabetic Foot ulcer?

The Diabetic foot initially presents with warning signs of an ulcer but hasn’t yet developed an active ulcer. This is called the Foot at Risk (Class 1). The foot then progresses to become the Ulcerated foot (Class 2) where a non-healing ulcer develops but remains free of invasive infection or is un-associated other complications. The next stage, the Crippled Foot (Class 3) is one where complications such as invasive soft tissue infection or osteomyelitis have developed or the ulcer is associated with other factors such as critical limb ischemia or Charcot osteoarthropathy which require to be addressed in addition to treatment of the ulcer. Most of the diabetic foot ulcer patients seek medical attention at this stage. This foot requires some form of reconstructive surgery for wound healing. The last stage is where the patient presents with the neglected foot with massive spreading infection which poses an emergent risk to the life of the patient or is not amenable to reconstruction due to severe structural loss. Such feet, the Critical foot (Class 4) are best managed by early amputation as a life-saving measure. Early amputation and prosthetic rehabilitation also enhance the quality of life those with non-reconstructable disease.

9. What are the usual treatment modalities of a Diabetic Foot Ulcer?

Diabetic Foot ulcer patients usually require treatment based on the stage (vide supra) of their presentation.

The earlier they present – simpler is the mode of therapy and lesser is the risk of losing the limb.

Class 1 – Foot at risk patients are usually treated by conservative methods such as provision of customized footwear, preventive podiatry measures like shaving of calluses, nail trimming, pedicure to remove dry and cracked skin, application of emollients etc.

Class 2 – Ulcerated foot – These patients usually require a trial of customized footwear. If the ulcer fails to stably heal with footwear then some form of surgery (Surgical Offloading) is done to correct the altered biomechanics and restore the efficient shock absorbing capacity of the foot. Such surgery is usually less traumatic, and allows the surgeon to predictably heal wounds in the diabetic foot. This is preferable for patients to undergo such early preventive surgery in a controlled setting rather than to procrastinate and be forced to accept emergency surgery in the uncontrolled setting of an un ulcer with invasive infection and abscess formation (Class 3).

Class 3 – Crippled Foot- Patients with complications usually require initial emergency surgery to control the infection. This may involve removal of the gangrenous areas of the foot and opening up of tracts of pus spread. Once the infection is controlled these patients are then taken up for some sort of Plastic surgical procedure to achieve wound cover (Reconstructive Surgery). Subsequent preventive surgery may be required toprevent recurrence of the ulcer once the patient starts walking again.

Class 4 – Critical / Non-reconstructable foot. These patients usually benefit by some sort of major amputation (Ablative Surgery) either as a life-saving or palliative measure aimed at improving mobility and hence the quality of life[2].

10. What are the alternate therapies to surgery for treatment of the Diabetic Foot ulcers and what is the status of current evidence for their use?

Some of the Alternative therapies to Surgery for diabetic foot ulcers include Hyperbaric Oxygen Therapy (HBOT), Platelet Rich Plasma (PRP) Therapy, Honey dressings and specialized creams and dressings which are promoted by various groups with claims of extraordinary success. However, currently available Medical literature states that there is very little evidence to prove that these alternative therapies are successful forms of treatment for Diabetic Foot ulcers in the long term. There is however some evidence that they may be useful in the short term healing of ulcers[3–7].

11. What are the self-care measures that patients with Diabetes need to follow to prevent ulcers or their complications?

Measures to prevent foot ulcers in Diabetics

  1. Please observe your feet on a daily basis (please enlist the help of others if you are not able to do it yourself)
  2. Wash your feet with a non-drying soap (moisturiser rich) and water.
  3. Apply a moisturizing cream twice a day to all areas of your feet below the knees. Keeping your skin soft & supple reduces infections.
  4. Cut your nails in a straight line. Avoid leaving sharp edges.
  5. Seek medical help if you develop calluses (thick skin) on the soles of your feet.
  6. Beware - calluses are precursors to chronic wounds.
  7. Get your feet tested for loss of sensation. Difficulty in retaining footwear or a feeling of walking on a cotton mattress are symptoms of sensory loss in the feet.
  8. Avoid wearing tight fitting footwear.
  9. See your doctor immediately even when you have minor problems like a shoe bite, nail Infection or cracks in the skin in between your toes. They may lead to major problems if ignored. Do not delay for the lack of pain.
  10. Those with deficiency of sensation should preferably avoid hot water soaks, native medical bandages and unproven herbal medications for foot problems.
  11. Seek urgent medical help if you develop sudden redness warmth and swelling of your feet (with or without fever and pain).
  12. Any wound that has not healed in 2 weeks may require plastic surgical intervention for healing. Ask your doctor for more information.

12. What is the best type of Footwear for persons with Diabetic Foot Ulcers and are all MCR footwears the same?

Customized therapeutic footwear is the most effective type of removable footwear for people with Diabetic foot ulcers[8,9]. Footwear should be worn at all times both within and out of the house. In India most people avoid wearing footwear inside the house considering cleanliness. However, such people can have separate pairs of footwear for use inside and out of the house.

Footwear can be made of different materials like Micro Cellular Rubber(MCR), Polyurethane foam, MCP etc. All materials provide adequate cushioning but however vary in their durability and tendency to get compressed and flatten out (Bottoming out)[10]. Once the footwear gets flattened out it loses its effectiveness and must be changed. Cheaper footwear tends to flatten out and become ineffective earlier. Hence patients must learn to balance cost with durability and effectiveness and choose the correct footwear for themselves.

13. How can you identify areas of high pressure in the foot?

Areas of high pressure can be recognized by examination of the foot and the pressure quantified by the use of various pressure monitoring devices (Pedobarogram). Examination of the foot reveals the formation of calluses in areas of high pressure. These calluses if not removed can hasten tissue damage by increasing the pressure on the underlying tissues by 26% resulting in the formation of ulcers[11]. Hence any skin thickening on the sole of the foot must immediately be brought to the notice of a foot care provider and appropriate professional advice followed.

Suggested further reading for more information - https://tinyurl.com/diabeticfootulcers

1.  Aleem MA. Factors that precipitate development of diabetic foot ulcers in rural India. Lancet (London, England) 2003;362(9398):1858.

2.  Sabapathy SR, Periasamy M. Healing ulcers and preventing their recurrences in the diabetic foot. Indian J Plast Surg 2016;302–13.

3.  ull AB, Cullum N, Dumville JC, Westby MJ, Deshpande S, Walker N. Honey as a topical treatment for wounds. In: Jull AB, editor. Cochrane Database of Systematic Reviews. Chichester, UK: John Wiley & Sons, Ltd; 2015. page CD005083.

4.  Kranke P, Bennett MH, Martyn-St James M, Schnabel A, Debus SE, Weibel S. Hyperbaric oxygen therapy for chronic wounds. In: Kranke P, editor. Cochrane Database of Systematic Reviews. Chichester, UK: John Wiley & Sons, Ltd; 2015.

5.  Storm-Versloot MN, Vos CG, Ubbink DT, Vermeulen H. Topical silver for preventing wound infection. In: Storm-Versloot MN, editor. Cochrane Database of Systematic Reviews. Chichester, UK: John Wiley & Sons, Ltd; 2010. page CD006478.

6.  Dumville JC, O’Meara S, Deshpande S, Speak K. Alginate dressings for healing diabetic foot ulcers. In: Dumville JC, editor. Cochrane Database of Systematic Reviews. Chichester, UK: John Wiley & Sons, Ltd; 2013. page CD009110.

7.  Dumville JC, Deshpande S, O’Meara S, Speak K. Hydrocolloid dressings for healing diabetic foot ulcers. In: Dumville JC, editor. Cochrane Database of Systematic Reviews. Chichester, UK: John Wiley & Sons, Ltd; 2013. page CD009099.

8.  Bus SA, Valk GD, van Deursen RW, Armstrong DG, Caravaggi C, Hlaváček P, et al. The effectiveness of footwear and offloading interventions to prevent and heal foot ulcers and reduce plantar pressure in diabetes: a systematic review. Diabetes Metab Res Rev 2008;24(S1):S162–80.

9.  Fernandez MLG, Lozano RM, Diaz MIG-Q, Jurado MAG, Hernandez DM, Montesinos JVB. How effective is orthotic treatment in patients with recurrent diabetic foot ulcers? J Am Podiatr Med Assoc 103(4):281–90.

10. Bal A. Diabetic Foot - ECAB. Elsevier Health Sciences APAC; 2012.

11. Young MJ, Cavanagh PR, Thomas G, Johnson MM, Murray H, Boulton AJ. The effect of callus removal on dynamic plantar foot pressures in diabetic patients. Diabet Med 9(1):55–7.

 

1a. A patient with an uncomplicated (Stage 2) Diab...
1b. Left Great toe ulcer completely healed after G...
2a. Uncomplicated (Stage 2) Diabetic Foot Ulcer of...
2b. Right 2nd toe tip ulcer heled completely after...
3a. Complicated (Stage 3) forefoot ulcer with pus ...
3b. Clean wound after debridement and excision of ...
3c. Wound healed by Skin Grafting (Reconstructive ...