A patient presented with foot drop with plantar ulcer on the heel. he was found to have erythematous plaques with zones of hyposensitivity

A PATIENT PRESENTED WITH FOOT DROP WITH PLANTAR ULCER ON THE HEEL. HE WAS FOUND TO HAVE ERYTHEMATOUS PLAQUES WITH ZONES OF HYPOSENSITIVITY.

A ) GIVE THE DIFFERENTIAL DIAGNOSIS ?

B ) OUTLINE THE MANAGEMENT OF FOOT DROP AND PLANTAR ULCER ?

A 8 A ) DIFFERENTIAL DIAGNOSIS VV IMP

1 NEUROGENIC -

A ) Hansen disease

B ) Syringomyelia

C ) Pressure ulcer in paraplegics

D ) Spina bifida

E ) Diabetic neuropathy

F ) Alcoholic polyneuropathy

2 VASCULAR ( ARTERIAL ) -

A ) Peripheral vascular disease

B ) Arteriosclerosis

C ) Microangiopathy as in Diabetics

3 VASCULAR ( VENOUS )

A ) Venous stasis ulcer

4 SYSTEMIC CAUSES OF MALNUTRITION

A ) Vit B 12 def

B ) Severe avitaminosis

C ) Ulcers over deposits of gout

B ) MANAGEMENT OF PLANTAR ULCER WITH FOOT DROP

1 The key to successful management of a chronic ulcer would be to correctly identify the aetiology as well as the local and systemic factors that could be contributing to its nonhealing nature.

2 Once a clinical diagnosis is reached, the investigations recommended would be according to the concerned aetiology to confirm the clinical diagnosis and for further management

3 Simultaneous wound management is started.

4 Control of hyperglycaemia and off-loading of pressure is begun immediately.

STEPS OF HEALING ^^ / MANAGEMENT
INITIAL STEPS

1 DEBRIDEMENT

A ) Wound management begins with debridement.

B ) Surgical debridement should be aggressive to include removal of all surrounding hard callus, hyperkeratotic skin, all dead necrotic tissue, infected soft tissue and bone.

C ) vv imp The end result of debridement should be soft, nonkeratotic wound edges with a well-vascularized tissue bed

D ) During debridement, activation of platelets for control of haemorrhage leads to release of growth factors which begins the process of healing.

E ) vv imp After debridement wound bed preparation is started aimed at the goal of complete healing.

2 MICROBIOLOGICAL TESTS AND ANTIMICROBIAL AGENTS

A ) During debridement a deep tissue culture should be taken.

B ) Different studies have been done regarding the efficacy of deep tissue culture vis-a-vis swabbing with some claiming swabs to be as effective as deep cultures and some concluding that deep tissue cultures are more relevant.

C ) During debridement, after the superficial tissue is removed till a viable bed is reached, a tissue piece is removed from the depth for culture using a rongeur or blade.

1 - This should be the most reliable tissue culture for starting appropriate systemic antibiotic therapy

2 - Systemic antibiotics, oral or parenteral, are required only in the acute infective phase, in the presence of cellulitis or failure of a properly treated wound to heal.

D ) Clinical signs of infection include purulent secretions, two or more signs of inflammation (e.g. pain, redness, erythema, warmth, tenderness and induration), foul odour and presence of necrotic tissue.

E ) Once debridement is done topical antimicrobial therapies are adequate to help eliminate bacteria in the foot ulcer.

3 WOUND BED PREPARATION - includes

A ) Moist wound dressings

1 A moist wound environment facilitates rapid migration of keratinocytes across the wound bed.

2 During a moist wound dressing, balance should be maintained between keeping the wound as moist as possible while avoiding maceration of the surrounding tissues.

3 Classically moist wound dressings were done by keeping the wound wet with a constant irrigation fluid or by using an intermittent spray. With recent advances in dressing materials, advanced moist wound therapy (AMWT) can be easily given with hydrogels (INTRASITE Gel, Smith and Nephew, Hydroheal, Dr. Reddys) and alginates.

B ) Dressing material selection

1 Among the topical antimicrobial therapies available, mention needs to be made of the silver cation which is effective at eliminating antibiotic-resistant strains of bacteria.

2 Silver is available in different types of applications-silversulphadiazine creams, silver ion with hydrogel dressings (e.g. Hydroheal AM, Megaheal), silver nanocrystals barrier dressing (e.g. Acticoat).

3 The silver barrier dressings destroy bacteria within the wound and as the antimicrobial barrier remains effective for up to 3 days it increases convenience for the patient and caregiver.

4 Wounds which are exudative can be dressed with hydrocolloid dressings which can absorb the exudate.

5 Dressing selection should be reassessed at regular intervals.

C ) Vacuum-assisted closure (VAC)/negative pressure wound therapy (NPWT)

1 Use of NPWT has increased over the years, and it is now a viable option.

2 It is used after debridement in trophic ulcers for wound bed preparation leading to delayed primary or secondary wound closure.

3 Results of a large NPWT randomized controlled trial demonstrated that NPWT is as safe as and more efficacious than advanced moist wound therapy (AMWT) in the treatment of diabetic foot ulcers.

4 A significantly greater number of NPWT patients achieved complete ulcer closure and granulation tissue formation than AMWT patients. They also had decreased length of time required for ulcer healing compared with AMWT.

D ) Hyperbaric oxygen therapy (HBOT)

1 HBOT is effective in the treatment of severe diabetic foot ulcers and should be utilized if available

2 Benefits may be seen in those patients who are ischaemic and it may avoid amputations

3 The Consensus Development Conference of the American Diabetes Association has recognized the value of adjunctive hyperbaric oxygen in difficult cases, stating that ‘It is reasonable to use this modality to treat severe or limb-threatening wounds that have not responded to other treatments, particularly if ischaemia that cannot be corrected by vascular procedures is present’

E ) Growth factors

Topically applied growth factors may accelerate healing by stimulating granulation tissue formation and enhancing epithelialization. Single or isolated growth factors may be effective in healing diabetic ulcers, like platelet derived growth factor (PDGF).

4 Off-loading measures

A ) Offloading pressure off the ulcer is the KEY to successful management of a trophic ulcer.

B ) Offloading can be in the form of strict bed rest, use of crutches, wheel chairs, walkers, pressure reducing measures like aircushion, waterbeds, plaster boot (total contact casting), removable contact casting, half shoes or specialized footwear.

C ) Transition from one offloading measure to the other should be slow. For example if a patient has been on bed rest and leg elevation, moving on to dependence and mobile offloading measures should be done in a graded manner.

D ) No offloading device will be of any benefit if it is not used consistently and if compliance is poor.

E ) Once the ulcer heals, in the early phase (6–8 weeks) it is yet liable to breakdown and more restrictive types of offloading devices need to be used before the patient can graduate to specialized footwear.

F ) The problem of recurrence persists because appropriate use of off-loading is very often not done.

G ) Cavanagh and Bus’s study on offloading pressures states that there is strong evidence to prove that uncomplicated plantar ulcers can heal in approximately 6 to 8 weeks with strict offloading.

H ) The best off loading device is a total contact cast (TCC)/plaster boot.

1 vv imp TCC should be applied only after debridement and removal of all dead tissue. Its greatest advantage is that the problem of unreliability is taken care of as it is a nonremovable device.

2 The drawbacks of a plaster boot are that it is technically demanding and if wrongly applied can lead to more ulcers.

3 It does not allow daily inspection and cannot be used in ischaemic ulcers.

4 The problem of a removable plaster cast is that patients tend to remove it more often than not, resulting in the off-loading becomes unreliable.

I ) Once ulcers are healed, for preventive care special orthotic devices or footwear can be made to keep pressure off the high pressure areas.

J ) In-shoe pressure measurements may be required to evaluate therapeutic shoe prescriptions in certain individual cases.

K ) The full-length shoe total contact insert also provides pressure reduction with optimal compromise for cosmetic acceptance and function

5 Reconstructive options

A ) Surgical options for reconstruction should be considered for ulcers which have exposed bone, tendons and when the area of the ulcer has not decreased by more than 10% after sincere conservative management for 2 months V V IMP

B ) Surgical options can range from skin grafts to local , regional or free flaps depending on the available donor tissue and the requirements of the defects

C ) Common flaps done for foot ulcers are local transposition flaps, medial plantar artery flap, fillet flaps, distally based sural neurocutaneous flaps, VY plantar flaps and local muscle flaps.

D ) *** tendon imbalance correction, particularly Achilles or gastroc-soleus tightness correction can help address foot problems and avoid ulcers.

E ) Flexor tenotomies have also been suggested to decrease metatarsal head ulcers in patients with claw toes.

6 NERVE DECOMPRESSION

Serves as an adjunct therapy to medical treatment should be used when there is clinical and/or electrodiagnostic evidence of compression neuropathy

7 MISCELLANEOUS

A ) Foot/nail care

1 A daily foot check should be part of the patient’s routine from the preventive aspect.

2 Look out for fungal infection in the toenails. The toenails may also harbour bacteria.

3 Topical antifungal agents can be used if fungal infection is diagnosed.

4 If required debridement of the infected nail may have to be done.

5 Routine grooming of nails and feet should be done in all cases of neuropathic feet.

A ) This includes regular trimming of nails, treatment of ingrown toe-nails and application of skin creams to keep the skin and nails soft.

B ) Avoid smoking and tobacco

1 VV IMP Smoking reduces the rate of O2 intake and delivery to the wound site and retards wound repair.

2 Nicotine, carbon monoxide and hydrogen cyanide in the smoke also have a toxic effect on platelets and inhibit normal cellular metabolism which creates a deleterious environment for healing.

3 IMP Smoking is a risk factor due to its effects of vessel constriction (short-term) and the enhanced development of atherosclerosis (long term).

4 An increase in complications after primary amputations of the lower limb in patients who continued to smoke cigarettes postoperatively have been documented with rate of infection and reamputation being 2.5 times higher than that of nonsmokers.

C ) Objective wound measurement/record keeping

1 Records of treatment, ulcer size and behaviour are an essential part of management as it keeps the treating surgeon and the patient aware of progress.

2 Recordkeeping should be done by two methods-(a) photographic record of the ulcers, (b) document the length, breadth and depth measurements of the ulcer at weekly intervals.

3 If the patient is on a home care regime measurements can be recorded by the caregivers at home.

4 vv imp It helps to objectively analyse healing and motivates patients towards self-care.

D ) Patient education and home care

1 Patient education empowers the patient and their caregivers towards preventive measures.

2 All high-risk individuals should have the benefit of disease specific education which can be in the form of one on one explanation by the primary physician, books, pamphlets, videos and/or disease support groups.

3 The following are essential:

A ) Explanation in simple terms about their specific pathology.

B ) Understanding that changing habits and making a few lifestyle changes could go a long way to keep progression of disease and its consequences in check, e.g. leg elevation whenever possible, changing position to keep pressure off one point.

4 Cessation of smoking.

5 Regular chiropodist care (foot and nail grooming).

6 Strict glycaemia control for diabetics.

7 Compression for venous diseases.

8 Daily end of day check of hands and feet for signs of breakdown.

9 Self-monitoring of sole/fingertip temperature.

10 Specialized footwear for off-loading pressure.

11 Regular follow-up with physician even in periods of no ulcer stage.

TREATMENT OF CONCOMITANT FOOT DROP

A ) Pharmacologic Therapy

1 If painful paresthesias develop, they can sometimes be effectively managed with sympathetic blocks or laparoscopic synovectomy.

2 Alternative treatments are amitriptyline, nortriptyline, duloxextine, pregabalin, and gabapentin.

3 Local treatment with transdermal capsaicin or diclofenac can also reduce symptoms.

4 vv imp Erythropoietin is a naturally occurring hormone that is approved by the US Food and Drug Administration for the treatment of anemia but also has neuroprotective and, possibly, neurotrophic properties.

A ) The proposed mechanism of action is antiapoptotic and anti-inflammatory, promoting cell survival.

B ) Erythropoietin is given in three doses of 5000 U/kg over 1 week after nerve injury. It has a minimal side-effect profile.

C ) An animal study showed that erythropoietin treatment accelerated functional recovery after peripheral nerve injury.

B ) Thru use of Ankle-Foot Orthosis

1 An AFO may be used for foot drop when surgery is not warranted or during surgical or neurologic recovery.

2 The specific purpose of an AFO is to provide toe dorsiflexion during the swing phase, medial or lateral stability at the ankle during stance, and, if necessary, pushoff stimulation during the late stance phase.

3 An AFO is helpful only if the foot can achieve plantigrade position when the patient is standing vv imp

4 The most commonly used AFO in foot drop is constructed of polypropylene and inserts into a shoe. If it is trimmed to fit anterior to the malleoli, it provides rigid immobilization. This device is used when ankle instability or spasticity is problematic, as is the case in patients with upper motor neuron diseases or stroke.

5 If the AFO fits posterior to the malleoli (posterior leaf spring type), plantarflexion at heel strike is allowed, and pushoff returns the foot to neutral for the swing phase. This provides dorsiflexion assistance in instances of flaccid or mild spastic equinovarus deformity. A shoe-clasp orthosis that attaches directly to the heel counter of the shoe also may be used.

6 A study by Menotti et al suggested that anterior AFOs are associated with lower energy costs of walking and higher levels of perceived comfort than posterior AFOs are and thus may allow people with foot drop to walk longer distances while expending less physical effort.

C ) Thru Nerve Stimulation

1 When foot drop is due to hemiplegia, peroneal nerve stimulation has potential advantages over an AFO, in that it provides active gait correction and can be tailored to individual patients.

2 A short burst of electrical stimulation is applied to the common peroneal nerve between the popliteal fossa and the fibular head.

3 This burst is controlled by a switch in the heel of the affected limb.

4 The stimulator is activated when the foot is lifted and stopped when the foot contacts the ground. This achieves dorsiflexion and eversion during the swing phase of gait.

D ) Options for Surgical Intervention

1 If foot drop is secondary to lumbar disc herniation (a finding in 1.2-4% of patients with foot drop), discectomy should be considered.

2 In the early phase of this condition, decreased blood flow due to compression is thought to lead to nerve-root ischemia.

3 The nerve root is more susceptible to compression injury than the peripheral nerve is because the vascular network of the nerve root is less developed, with no regional arteriolar blood supply.

4 Foot drop due to nerve-root injury may depend on the magnitude and duration of nerve-root compression.

5vv imp Early decompression is recommended in cases accompanied by severe motor disturbance, especially in older patients.

6 A review of surgical management of peroneal nerve lesions demonstrated that neural repair is the first priority in selected patients with peroneal nerve palsy.

A ) This may be accomplished by means of nerve decompression (either central or peripheral) or nerve grafting or repair.

B ) For foot drop from deep peroneal nerve injuries of less than 1 year’s duration, one study reported success in transferring functional fascicles to deep peroneal-innervated muscle groups, with either the superficial peroneal nerve or the tibial nerve used as a donor

C ) If sufficient recovery is not achieved with those measures, tendon transfer procedures (see below) may be considered.

D ) It has been suggested that a tendon transfer may be considered if there is no significant neural recovery at 1 year.

E ) If a foot drop is chronic and accompanied by contracture, lengthening of the Achilles tendon may be necessary to achieve adequate dorsiflexion.

Fv) vv imp In patients in whom foot drop is due to neurologic and anatomic factors (eg, polio or Charcot joint), arthrodesis may be the preferred option. The goal is to achieve a stable, well-aligned foot and ankle.

1 This may be accomplished by means of ankle arthrodesis, Lisfranc arthrodesis, and triple or pantalar arthrodesis, with or without lengthening of the Achilles tendon.