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claudicação intermitente

Mar 06, 2016

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Ana Azevedo

claudicação intermitente
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Intermittent Claudication

Intermittent ClaudicationEarly peripheral arterial disease (PAD) commonly presents as claudication, a term derived from the Latin claudico meaning to limp. (Ward, 1998) Intermittent claudication is described in the literature as a transient, exercise induced ischemic myalgia characterized by aching, cramping, tiredness, or tightness of the affected muscle compartment (Ward, 1998). The calf being the most commonly effected (Ward, 1998). When normal muscles are exercised , metabolic by-products are released resulting in relaxation of smooth muscle in the arterioles, venules and pre-capillary sphincters. The resistance in these vessels greatly decreases. Since blood flow is inversely proportional to resistance, blood flow to the healthy exercising muscle will increase 10-20 times and thus meet the increased metabolic demands of that muscle, removing the noxious metabolic end products (Ward 1998). When an individual with significant organic occlusion participates in exercise, relaxation of the smooth muscle in the arterioles, venules and pre-capillary sphincters still occurs, a problem arises due to the fact that the occluded vessel is narrowed and uneven due to plaque deposition. The amount of blood that is able to pass this occlusion per unit time is greatly limited, the end result being that the demand of the exercising muscle is not met. Pain is felt when the accumulation metabolic by-products within the muscle is at high enough concentrations to activate pain receptors, more exercise results in more pain. Once the individual stops exercising, the rate of metabolism within the muscle decreases, the blood flow to the muscle can then wash away the high levels of metabolites and the individual will then achieve symptomatic relief (Ward, 1998).

The locality of pain usually correlates with the location of the occlusion, pain is usually perceived one segment distal to the obstruction, i.e., toe pain usually reflects an occlusion in the midfoot, calf pain an occlusion in the knee or distal thigh and so forth (Hoffman 1992). It is important to correlate the patients history with the physical findings and to clearly identify whether the patients pain is of ischaemic origin, and to exclude any differential diagnoses. Ischemic pain is worse during exercise and is located in muscles, whereas arthritic pain is located in joints, the patient whos pain is of ischaemic origin is more likely to suffer earlier onset of symptoms when walking up hills. Pain of neurologic origin probably correlates with back pain and is noticed in specific positions (Hoffman. 1992). If the patients main presenting complaint is more severe at rest and the patients ABPI is greater than 0.8, the pain is not likely to be of ischemic origin. It is important to ascertain and note how far the patient can walk before requiring rest, this allows a semi-quantitative measure for future inquiries, it is also important to enquire as to any changes/progression the pain has made since it was first noticed.

An introduction to manufacturing EVA orthoses, and use of other moldable thermoplastics

There are many different materials available for use in the fabrication of orthoses, and the ability to choose an appropriate material for devices is as important as any other prescription variables within the device.

There are circumstances where the most effective treatment of a patient will include exerting an influence on gait and plantar pressures during stance phase. Some of these circumstances will involve conditions where a rigid cast orthosis is not a practical solution. Factors that effect the path of action can include the desires of the patient, the cost of the various treatment options, the symptoms and diagnosis of the patients condition and the primary underlying causes of the presenting complaint. This is not an attempt to outline issues such as this in any comprehensive way, but rather an indicator that much thought and consideration of options should precede any action.There are circumstances where a practitioner may be unable to aim for what they believe is the theoretically correct or best answer because of issues relating to patient compliance, extremes of activity by patients or complicating health issues related to disease processes and many other confounding problems. These factors are real but should not discourage the practitioner from their best efforts in attempting to solve problems and improve quality of life for patients.There are times when significant improvement in patient comfort can be achieved using plantar pressure spreading methods with the use of materials that are much softer than the materials used for cast rigid devices.Sometimes a patient may be unable to tolerate the more rigid materials and the medium density foams may offer both pressure relief and comfort.There are many different semi-rigid and soft materials available that are heat mouldable at fairly low temperatures. Their physical properties vary greatly and the desired set of characteristics will vary depending on each circumstance. Consideration of patient activities, specific conditions, desired outcomes and other factors will be required. In general terms the softer materials will exert a less specific effect on gait. When choosing materials bear in mind the age and body weight of the patient. The 90 to 250 density materials tend to be better for children and where a more comfort oriented solution is sought for adults. The 300 to 450 density EVA'S are really quite hard and are used as posts for rigid orthoses so when using these it can be important not to effect the foot too aggressively.Commonly used and cost effective materials include Ethylene Vinyl Acetate (EVA) , Plastazote, "polydorane" (which seems to be Smith & Nephew Easy cast with the appropriate heating curve), and blown polypropylene. This is not meant to be a comprehensive list of options but is an attempt to encourage students to experiment with a variety of materials that will increase the range of solutions available to their patients in the future.

EVAThe common forms of EVA foam are pressure blown (nitrogen gas) closed cell foams with small cell sizes. It is available in a range of densities (varying Young's Modulus of compression). Common densities are rated according to how many kilograms they weigh per cubic metre. The normally available densities include, but are not restricted to 45, 90, 120,220,270,350 and 400kg per metre cubed. To get a feel for these it is best to mold and grind and actually wear/use them yourself to begin to understand what results you can achieve with each different density.There is very little published information in relation to this subject. However there is a clinical history of positive feed back from patients and practitioners over many years. A suggested reading list will be offered at the end of this piece that may help encourage students to follow this area up a little more. More definite insights will no doubt arise as research in biomechanics and orthoses of a variety of types continues. The author has no doubts about the reality of benefits/improvements that are possible. The key is to stay focused on doing the best job you can for each patient and be encouraged by the positive feedback that will follow.Construction of non- rigid devices is an iterative process where the first attempt may not be the best and patient feedback is crucial to a final approach to the best answer for any given individual. It must be borne in mind that there are many patients out there for whom a complete resolution of symptoms is not possible, particularly in the area of rheumatoid arthritic conditions. This should not discourage you from making the best of the situation for the patient through palliative load spreading methods.

Immediately after vacuum pressing Immediately after rough grinding

Web Resources

Click here for a link to a lecture from the University of Western Sydney, discussing the material properties of orthoses.

Langer Biomechanics (a large orthoses lab in the USA - information about products, services and some biomechanical information)PFOLA (Professional Foot Orthoses Laboratories of America - information about the organisation)ISB Footwear Biomechanics (International Society of Biomechanics - abstracts and articles pertaining to previous and upcoming conferences and seminars looking at footwear biomechanics)Orthopaedic Topics (knock yourself out! - lots of information)Superfeet (manufacturer of orthoses for a range of sporting applications)Rieckens Orthotic Laboratory (another orthoses lab in the USA)Manufacturing EVA orthoses: a basic guide

The Manufacturing ProcessFirst decide which density or densities of EVA are apropriate based on patients' weight, uses and degree of effect wanted.Prepare suitable sized pieces and laminate them together with contact adhesive.Heat flat blanks until they are soft - not burnt. See for yourself and your oven how long this takes.Have a piece of 1.5 to 3 mm Poron (or sox) available to protect your patient from the heat of materials during direct molding.Click here for a more vertical view of the Jetronic molding system

Quickly set the patient up on soft blanks on top of the chosen molding pillows using protective layer on top of hotter materials. The second method pictured is a partial weight bearing system using a molding box with tightly stretched rubber membrane over which the heated blanks are placed and the a seated patient pushes their feet into the soft blanks.

While waiting for the material to cool it pays to draw a suitable heel cup border in with a biro (and an outline of the toes on full length devices). This is not always necessary, but you can't do it later if the patient leaves while you finish off the grinding. Always leave full length devices long until actually fitting to the patients footwear.

The grinding process requires excess material to be removed from both lateral and medial sides. It works better if these borders are fairly straight, but angled to the sagittal plane to facilitate shoe fitting (see pictures below).

Click here for a detailed view of grinding the medial border of an EVA device

The heel cup needs to be finished so as to fit the footwear concerned but a good generic shape is pictured. A common problem is too much material left under the heel for the device to easily fit in shoes. The finishing process should use a diferential grind height for heel and forefoot similar to finishing a rigid orthosis (see below). This seems to allow a better seating of the finished article in footwear. Heel height should finish somewhere between about 14 and 22mm after the plantar surface of the heel has been ground thin (approx 3 mm).Posterior view of ground EVA device. Note the angulation of the medial and lateral grinds relative to vertical.

When grinding the plantar heel, note that the forefoot is 4mm (with an average heel pitch - this can vary between shoes depending on heel height) below the plane of the grinding surface. When grinding the forefoot, note that the plantar heel surface is 4mm above the forefoot . The brown spacers seen above elevate the heel for forefoot grind, and are removed to allow the plantar heel grind.

The forefoot can be finished to incorporate features such as a valgus wedge or Dananberg style Kinetic wedge which leaves a device that is all in one piece and easy to accomodate within footwear. To achieve a variety of features the devices can be ground from the plantar surface to vary the thickness of material left under the foot.In the picture on the left, note the valgus forefoot wedge that has been ground into the device.

The process of adding a smaller and denser rearfoot post or stabiliser is simple. Cut the desired small piece and cover with glue, and place in oven to soften. Cover place on previously molded first layer (when cool) with glue and then laminate by hand when the small piece is soft. Some grinding may be required for aesthetics and to facilitate shoe fitting.

EVA devices can also be made using plaster casts in the usual vacuum press manner as for rigid orthoses. It could be argued that this allows for more precise results and control of the foot during casting. Plaster additions can be made to the foot in the same or different ways as is performed for rigid orthoses.

It is possible to use a simple foam block under the patients' foot for the molding process and this will work, however manufactured molding pillows are relatively inexpensive (~ $140) and have a long lifespan so the acquisition of a pair is justified if you intend to do this frequently. Heating of materials can be done in a small toaster oven that costs as little as ~$110 and it has been known to be done with a hot air gun .

Direct molding can be done to the foot of a prone patient however the speed and convenience of weighted or partial weighted molding makes these options fairly good ones. The method pictured here is a commercially available system incorporating preformed molding pillows, a heating drawer and a" podoscope" that gives a rudimentary view of the pattern of weight bearing of the plantar aspects of the feet.

Cost IssuesThe question of benefit versus cost to the patient or cost to the taxpayer remains an issue. It suffices to say that with practice and familiarity these direct molded devices can be made during one 30 minute consultation from materials ranging in cost from as little as $5 through to approximately $40. For the cost of a consultation and materials the patient may end up with a product with a life span of years that offers significant improvement in comfort. It is worth emphasizing that speed of production is a significant issue in relation to keeping costs down for the patient and this speed depends on a willingness to practice. Speed can also be improved by use of prefabricated, two dimensional blanks that are precut and just need to be molded and finished off. These save time and effort and are offered in quite a variety of forms in a range of materials.It is also worth mentioning that these types of devices can significantly improve sporting performance in the medial edging sports such as snow skiing, roller blading and ice skating. (See Langer Laboratory orthoses web site and others).Grinding and finishing can be performed with any standard grinder. 80 or 100 grit silicon paper works fine for all these materials. They all have slightly different grinding characteristics but again practice solves any problems.Occupational Health and Safety IssuesThe main issues are eye protection, ear protection and lung protection. Solutions to these problems are fairly obvious : wear your protectionThe particle size produced when grinding is the major factor as far as inhalation danger goes. Some materials produce relatively large particles (30 microns) which don't float around in the air so well and do get filtered out by grinder suction systems. Some materials throw much smaller particles (under three microns) and it is particles in this range that are much more dangerous. Most grinders come with filter systems that filter down to only about 30 microns, so all the fine stuff gets blown out through the bag for you to inhale. The most cost effective solution is to have an external exhaust because industrial systems that filter down to ~1 micron start at about $5000. There are small HEPA (high efficiency particulate air) filters on the market from ~$250 that can greatly improve air quality in small spaces (good for fungal spores in treatment rooms) but don't hook up directly to grinders. Further information on workplace safety is available from the Victorian government WorkCover department.Less obvious issues include the potential toxicity of glues and solvents. Toluene which features in some contact cements can have serious effects on some people at lower levels than historically predicted. It's not just when you are grinding that you need to be careful.. Allergenic reaction to materials can also occur.

Web Resources

Click here to view an illustrated guide to manufacturing a simple template for use in non-cast insoles (from the University of Western Sydney website).

Introduction to EVA Orthoses

Phillip CarterAn Introduction to the Total Contact Cast & Ambulatory Fibreglass Boot The following webpages include information about two types of rigid casting used in podiatry - the Total Contact Cast (TCC) and the Ambulatory Fibreglass Boot (AFB). Below is an introduction to the significance in treating foot ulceration, with indications, contraindications, advantages, disadvantages and patient instructions for each. Linked to this page are comprehensive pictorial guides to application of each of these casts.

Total Contact Cast Application Ambulatory Fibreglass Boot Application

Introduction

Diabetes Mellitus is a common disease affecting more than 350 000 Australians in 1990 and is estimated to affect 900 000 Australians by the year 2000. Diabetes Mellitus is a condition that has both personal and public health implications. On an individual level Diabetes Mellitus may have enormous emotional, social and economical and physical effects on the individual. Payne &Scott (1997) estimated the annual total inpatient cost for diabetic foot disease in Australia to be $48 - $53 million indicating that Diabetes Mellitus is a financial dilemma for the public health system.The treatment of diabetic foot ulcers has been a difficult task for Podiatrists and other health professionals in the past. The introduction of Total Contact Casting and Ambulatory Fibreglass Boots as a method of neuropathic ulcer treatment has allowed effective short term healing of plantar wounds by effectively reducing mechanical stresses and pressures on the plantar surface of the foot. Total Contact Casts and Ambulatory Fibreglass Boots allow the patient to be ambulatory and reduces lengthy and expensive hospital costs associated with complete bed rest, nursing care and lower limb amputations. These treatment methods also allow the patient to maintain employment, so there is no income loss for the individual.Over the years there has been a lot of research undertaken that investigates the effectiveness of Total Contact Casts in the treatment of neuropahtic ulcers. The results in Table.1 prove that the Total Contact Cast reduces the healing rate of neuropathic ulcers. The average healing time from the studies examined is 6.1 weeks. Similarly, the Ambulatory Fibreglass Boot has also shown to reduce healing rates of neuropathic lesions in some cases. However, unlike the Total Contact Cast little research has been conducted using this method of treatment. The average healing time for Ambulatory fibreglass Boots taken from the literature available is 10.7 weeks (Table .1). This has lead researchers to believe that the Total Contact Cast may be the treatment of choice for neuropathic ulcers.TOTAL CONTACT CAST (TCC)HEALINGRATES (mean healing timeAMBULATORY FIBREGLASS BOOT (AFB)HEALINGRATES (mean healing time)

Borssen and Lithner (1989)10 weeksBurden, Jones, Jones & Blandford (1993)3 months

Gilbey (1991)4 weeksGilbey (1991)4-6 weeks

Diamond, Mueller & Delitto (1993)6 weeksJones (1990)(Good diabetes control;HbAlc 7% or less)6.1 weeks

Birke, Novick, Coleman, Patout (1991).Unpublished research.6 weeksJones (1990)(Poor diabetes control;HbAlc 7.1% or more)19.8 weeks

Walker, Helm & Pullium (1985)4.4 weeks(Forefoot ulcers)

Boulton, Bowker, Gadia, Lennerman, Caswell, Skyler, Sosenko (1986)6 weeks

Sinacore, Mueller, Diamond, Blair, Drury & Rose (1987)6.2 weeks

Table 1: Average healing rates of neuropathic ulcers using TCC & AFB.

THE TOTAL CONTACT CASTThe aim of the Total Contact Cast is to immobilise the foot in order to reduce the vertical forces during gait thus allowing the plantar ulcer or pre-ulcerous lesions to heal. Total Contact Casts also promote healing by controlling lower leg and foot odema and protecting the foot from trauma. (Kominsky 1994).INDICATIONS FOR TOTAL CONTACT CAST1. Plantar neuropathic ulcers.2. The post-operative surgical foot.3. Active Charcot neuropathic foot.CONTRAINDICATIONS FOR TOTAL CONTACT CAST1. Active or acute soft tissue infection.2. Abcesses, osteomyelitis & gangrene.3. Ulcer depth greater than ulcer width.4. Fragile skin5. Excessive leg or foot swelling6. Patient unwilling too have cast on extremity7. Patient unable to comply with follow-up visits8. Blind9. Obese10. Ischaemia ulcers with a doppler pressure < 0.411. Patients prone to falls have an increased risk of falling due to the Limb length discrepancy created by the cast.12. The cast creates a limb length discrepancy which may possibly induce hip and back pain.(Sinacore, 1988)ADVANTAGES1. Reduces healing time of plantar ulcers.2. Allows patient to maintain ambulation.3. Reduces excessive plantar pressures.4. Protects foot from further trauma.5. Controls odema.6. Allows patient to continue working.7. Cost effective.8. Doesn't require as regular changing compared to other modalities.(Sinacore, 1988)DISADVANTAGES1. Cast cannot be removed.2. Unable to visually assess for infection or ulcer progress until cast is removed.3. Joint stiffness and muscle atrophy if immobilization is prolonged4. Possible skin abrasion or new ulcerations if cast is poorly applied or not monitored5. Possible foul odour if drainage is excessive.6. Digital fungal infections due to moist environment in cast.7. Possible complications due to undiagnosed osteomyelitis after cast is applied.(Sinacore, 1988)Total Contact Cast ApplicationPRECAUTIONSThorough training and practice in cast application is required to ensure success and to reduce possible complications associated with immobilizing an insensate foot."Skill in plastercraft is not to be learned from books but only by continuous repitition..One who regards the application of plasters as a menial task is advised to transfer his attention to another speciality" - John Charnley (1950)The key to minimising potential side effects is strict monitoring of the ulcer, observing the patient's tolerance to the cast and most importantly careful application of the Total Contact Cast. Unless the patient is willing to comply with regular follow up visits casting should not be implemented.(Sinacore, 1988)PATIENTS INSTRUCTIONSThe patient must be supplied with a thorough list of written instructions on how to look after the cast and what complications to look out for whilst wearing the cast.These include;1. Walk as little as possible. This will put less pressure on the wound thus allowing it to heal faster.2. The leg with the cast will be longer than the other leg therefore this may put strain on the hip and back if you walk too much.3. You will be less stable when wearing the cast so the chances of falling are increased. The less you walk the less likely you are to fall. Be careful on slippery or uneven ground.4. You may wish to use a walking stick for added stability. If you were unsteady before the cast you should use a walker.5. The cast must not get wet. Take sponge baths instead of normal bathing or showering.6. Notify the Podiatrist or General Practitioner if any of the following occur;Any loosening or excessive mobility of the foot in the cast. A space of more than _ inch between the cast and leg is too much.A smell coming form the cast may indicate infection that started after the cast was put on.Any sudden tenderness in the inguinal lymph nodes.Any sudden increase in body temperature, fever or blood sugar levels.Any pain or discomfort.Any dents, cracks or other damage to the cast. These may apply dangerous levels of pressure to the leg/foot.Any drainage on the outside of the cast, particularly in regions not adjacent to the ulcer.Excessive swelling of the leg or foot, causing the cast to become too tight.

THE AMBULATORY FIBREGLASS BOOT (SCOTCHCAST BOOT)The aim of the Ambulatory fibreglass Boot is to redistribute foot pressures over the entire surface area of the sole of the foot thereby removing direct pressure from the wound site. It has proven to be effective in treating neuropathic wounds in some cases however as previously mentioned there has been little published research into the healing times associated with its use.INDICATIONS FOR THE USE AMBULATORY FIBREGLASS BOOT1. All types of neuropathic ulcers.

2. Neuropathic ulcers under the 1st metatarsal head and those under the hallux respondwell to this treatment. Ulcers under the lesser metatarsal heads also respond well totreatment. The heel is the most difficult to treat.

3. Mixed neuropathic/ischaemic ulcers may be treated with Ambulatory fiberglass boots however the degree of ischaemia will be the limiting factor as to whether this treatment can be used.

CONTRAINDICATIONS FOR THE AMBULATORY FIBREGLASS BOOT.

1. Ambulatory fibreglass boots are unsuitable for ulcerations which are wider than they are deep. If the ulcer is deeper than it is wide the surface of the ulcer may epithelialise before the base of the ulcer has time to heal. The premature closing of the ulcer would leave a cavity beneath the skin, increasing the potential for abscess formation.(Kominsky 1994)2. Certain dorsal and digital ulcers which are inappropriate due to their location.3. If the patient has an Ankle/Brachial Index (ABI) of 0.35 or less or is diabetic andhas an ABI of 0.45 or less then this treatment is contra-indicated as these ulcers willprobably not heal. (Wilson 1991).ADVANTAGES1. Redistribution of foot pressures.2. Custom built to suit the individual.3. Rigid and lightweight.4. Removable for redressing, bathing and sleeping.5. Patient remains ambulatory.6. Decreased healing time according to literature.7. Ability to assess progress of the wound.8. Inexpensive compared to hospital costs.(Wilson 1991)DISADVANTAGES1. Unaesthetic, bulky and hot2. Expensive3. May require an orthotic and possibly specialist footwear.4. Requires specialist application and therefore is not suitable for every clinical situation.5. Minimal use on digital ulceration.6. Contra-indicated in cases of ischaemia.7. Difficult to walk in due to the limb length discrepancy the cast creates.8. May increase the instability of patient therefore increase the number of falls.(Wilson 1991)Ambulatory Fibreglass Boot ApplicationPATIENT INSTRUCTIONS1. Patients should refrain from vigorous activities which could interfere with healing of the ulcer or cause fractures in the cast due to its lightweight, strong and water resistant properties.

2. Patients may swim, bathe or shower when clinically indicated.

3. Patients should be cautious against accumulation of foreign materials such as sand under the cast. Foreign objects may cause further irritation and cause other ulcerations to develop or cause infection of the existing ulcer if bacteria enters the wound.

4. If the cast becomes wet it should be dried with towels or a hair dryer if necessary.

5. Prolonged or frequent wetting of the cast without drying may produce macerated skin. This is the most frequent complication noticed with the Ambulatory fibreglass boot. (Albert, 1981).

Application of the Total Contact Cast (TCC)| Return to Casting IntroductionAmbulatory Fibreglass Boots application

Some of the materials used in the cast application process1. Prepare the footA. Debride toenailsB. Rehydrate skin with emollientC. Place cotton between toes to absorb moisture.D. Debride ulcer as necessary and apply light dressing. (Ulcer must be wider at the surface than it is deep).

2. Apply sockinette to the leg.A. Sockinette must be firm with no wrinkles.B. Fold sockinette dorsally over the toes, and tape it in place.C. Make a cut in the sockinette at the ankle joint level and seal it with tape.Please note that in the following photographs, the foot has been placed in a more plantarflexed position than it should be for this cast- the foot should be approximately at a right angle to the leg.

3. Apply a 3-inch wide strip of 7mm adhesive felt to the anterior aspect of the leg.Bevel the edges of the felt well. The felt must extend from the dorsum of the toes tothe tibial tuberosity.

4. Cut two circular pieces of felt large enough to cover and protect both malleoli, thentape in place. Bevel edges well.A piece of 4-inch foam is taped across the tips of the toes from the dorsum to plantarsurface of the foot.

5. Apply a 4-inch roll of plaster of paris to the foot and leg so that it extends from thebase of the toes to the proximal extent of the felt.Care must be taken to eliminate allbulges and folds of plaster, especially on the bottom of the foot.Hold the foot at 90degrees to the leg. Be sure to only use the flat surfaces of the hands and avoid usingfingertips.

6. Several layers of plaster of paris are applied to the bottom of the foot so it is perpendicular to the long axis of the leg. This create a rockerbottom sole aiding propulsion during ambulation.Alternatively, a 4-inch piece of plywood may beapplied to the sole of the foot to create the rockerbottom.

7. Apply a 3-inch roll of fibreglass to the foot covering the plaster of paris. Applyevenly and avoid bumps and sharp edges.A rubber walking heel may be placed on the sole of the foot just proximal to themetatarsal heads (optional).Complete the rest of the cast with 3-inch roll of fibreglass, covering the foam over the toes. One to two more rolls of material are usually used at this point.

8. The patient is required to remain in the office for approximately 30 minutes to allow for drying and to be sure that the fit is acceptable.When the cast is ready for changing a cast saw is used to remove the cast. The cast should be cut along the anterior border of the cast where there is felt padding protecting the leg.

Return to Casting IntroductionAmbulatory Fibreglass Boots application

Application of the Ambulatory Fibreglass Boot (Scotchcast Boot) Emily Carpenter, 1998

Total Contact Cast application | Introduction to Casting1. Sockinette is applied to the lower third of the leg, extending 10cm beyond the toes.

2. Mark the lesion. Apply felt padding to remove pressure from the wound site.

3. Using 7mm semi-compressed felt cut a slab to cover the sole of the foot so that it extends up both sides of the foot and the heel.Use additional 5mm felt for valgus fillers or wedges if required. Cut a window in the felt if required.

4. Wrap a strip of 5mm x 7-10cm wide felt or sponge rubber around the ankle for malleolar protection and secure with micropore.

5. Hold the felt slab securely in place with two rolls of 10cm Softban. Evenly distributed over the whole area. Mark the lesion if necessary.

6. Apply one roll of 2 inch fiberglass from the toes to the ankle. Apply the remaining 3 inch roll from the ankle to the toes.Be sure to rub the fiberglass well to get a smooth finish. REMEMBER TO ALWAYS WEAR GLOVES.

7. It is important to get the patient weightbearing in a normal stance position to facilitate ambulation - it is best to stand on a piece of foam or similar to prevent sticking to the floor.8. Once the cast is dry mark the lesion and cutting lines.

9. Using a plaster saw, bi-valve the cast on the dorsum and trim to the required height and length. Remove the bi-valve.

10. Cut the sockinette and turn the sockinette back over the ankle and toes and secure with 3 inch extension plaster.

11. Remove cast from the foot and seal the cut ends of the padding using 3 inch Extension plaster.

12. Apply a rubber sponge strip along the dorsum of the foot andankle.

14. Apply a 3 layer slab of fiberglass on the sole of the foot to create a rockerbottom sole.

15. Wrap another roll of fiberglass around the foot from the toes to the ankle.

16. Mark the bi-valve on the dorsum of the foot and cut with a cast saw.

17. Cover the edges of the cut fiberglass with extension plaster so there is no sharp cornersRefit the boot to the foot and hold firmly in place. A tongue pad of felt helps to add comfort and firmness.

18. Use a Post-Op walking shoe at all times when weightbearing. The cast can be removed and replaced as necessary for dressing, bathing and sleeping etc.