Diabetic Foot: A Comprehensive Guide for Clinicians Nihal Thomas, Felix Jebasingh K
Page numbers followed by b refer to box, f refer to figure, fc refer to flowchart, and t refer to table.
Abduction 16
Above-knee amputation 167
Abscess 160
tendon, shortening of 30
tenotomy 166
Adduction 16
Adjuvant therapy, efficacy of 182t
Advanced glycation end-products 27
Aeromonas hydrophila 170
Air cast boot 83f
Alcohol consumption, chronic 29
Aldose reductase inhibitor 41
Allodynia 29
Alpha-lipoic acid 40
Amitriptyline 38
Amoxicillin 59
Amputation 151, 162, 166
partial 167
previous 161
type of 167
Amyloidosis 29
Amyotrophy 26
Angiogram 105
Angioplasty 166
Angle-closure glaucoma 38
Ankle 9, 69, 71
and foot complex, motions of 16
brachial pressure index 52, 105, 106f, 107, 108, 111, 114
foot orthosis 62, 82f, 125
patellar tendon-bearing 127
joint 14, 66f
nerve supply of 15f
pressure 108
varus deformity of 127f
Anorexia 172
Antibiotic 165
carbapenem group of 176
duration of 100, 101, 165
resistance 165
therapy 163, 164, 176
duration of 101t
toxicity 165
Antiphospholipid antibodies 28
Arsenic 29
Arteriovenous systems 3
anterior tibial 15
bypass graft, postcoronary 121
Arthrodesis 166
active 78
inactive 78
Articulations 11
Asymmetric lower limb motor neuropathy 26
Autonomic dysfunction 3
Autonomic neuropathy 19, 26, 140
Below-knee amputation 115f, 167
Bilateral great toe dorsal foot ulcers 143f
Biopsy 81
Biothesiometer 35f
glucose 24
management 42
rapid correction of 29
sugars 128
urea nitrogen 36
Bohler iron cast 61f, 121, 122, 122f, 123f
Bone 10
biopsy 81, 98
fusion of 87
involvement 55, 60
abnormality, location of 79
edema 72f, 77f, 84, 85
necrosis 165
scan 80, 80f
Bony prominence, excision of 87
Brachial blood pressure index 52
Brodsky's anatomic-based classification systems 71
Burns 151
Calcaneal periosteum 97f
Calcaneal pitch 74, 75f, 76f, 87
Calcaneocuboid-intertarsal joint 69
Calcaneovalgus 22f
Calcaneovarus 22f
Calcium channel modulators 38
Callosities 138
Callus removal 57, 135
Capsaicin 39
Carbapenem 176
therapy 164
Cardiovascular disease 27
Cefotaxime 176
Ceftriaxone 59, 176
Cellulitis 50t, 51f, 85, 160
Cephalexin 59
Cephalosporins 176
Charcot's arthropathy 69, 70, 125, 126f, 128
classification for 71
diabetes-related 3
Charcot's foot 3, 52f, 66, 73, 7780, 84, 85, 87, 98, 98t, 123, 125
active 72f, 77f
acute 73f, 76f, 77f, 79
chronic 70f, 72f-76f, 78f, 86, 87
diagnosis of early-stage 76
management of 81, 86
middle- to late-stage 77
offloading of 82f
Charcot's joints 70
Charcot's neuroarthropathy 30, 73
exostectomy of 166
Charcot's neuropathic osteoarthropathy 3
Charcot's neuropathy 5
Charcot's restraint orthotic walker 62, 82
Charcot's walker 83f
Cilastatin 60
Ciprofloxacin 60
Claudication pain 30
Claustrophobia 80
Clavulanate 59
Claw toe 52f
Clindamycin 59, 60, 176
Clostridial collagenase ointment 182
Clostridial infection 178
Collagen sponge 164
Color Doppler ultrasound 105
Computed tomography 99
angiogram 105, 107, 114
scan 79, 80
Contrast-enhanced computed tomography scan 173
Contrast-enhanced magnetic resonance angiogram 105, 107
Corneal confocal microscopy 35
Coronary artery disease 121
Cortical fractures 77
Cranial mononeuropathy 31
Cranial nerve 31
Cranial neuropathy 26, 31
C-reactive protein 73, 94, 173
Creatinine 173
Crepitus 162, 172
forming lowermost bone 72f
fragmentation of 73f
height 74
Daptomycin 176
Debridement 56, 162
extent of 165
Deep fascia 12
Deep peroneal nerve 14
Deformity 6
Depressed tendon reflexes 29
Desipramine 38
Devitalized tissues, debridement of 161
Diabetes Control and Complications Trial 40
Diabetes mellitus 2, 24, 27f, 44, 69, 110f, 111f, 113f, 135, 160, 169, 171
type 1 25, 70
type 2 24, 70, 90, 119, 121, 125, 128, 130, 131, 150
Diabetic amyotrophy 41
treatment of 41
Diabetic foot 2, 3, 9, 34f, 51, 118, 119t
anatomy of 9
assessment of risk of 6f
biomechanics of 9
care 2
complications 44
disease 2, 118, 160
fissures in 140
infection 160, 164
severity of 55t, 59t
surgical treatment of 161b
types of 160b
management 180
osteomyelitis 90, 91, 96b, 100b, 160, 163b, 167t
antibiotic treatment of 164
diagnosis of 99t
pathogenesis of 91
surgeries in 160
therapy 144f
ulcer 2, 44, 46, 58, 104, 151, 157, 160, 162b, 180
classification of 46, 95t
etiology of 46
infection in 163t
pathogenesis of 46fc
prevalence of 135, 180
therapy 182t
Diabetic neuropathy 2, 19, 25, 36fc, 42
Diabetic retinopathy 44
Diabetic sensorimotor polyneuropathy 41
Diarrhea 172
Diffuse bone marrow edema 72f
Digital subtraction angiogram 105, 114
Distal trans tibiofibular amputation 167
Doppler arterial flow studies 52
Dorsalis pedis 123
Dorsiflexion 16
Doxycycline 59, 176
Duloxetine 38
Dundee classification 50t
modified 50
Ecchymosis 172
Eichenholtz classification system 71
Electrical spinal cord stimulation 40, 42
Electromagnetic nerve stimulation, frequency-modulated 40
Electromagnetic therapy 182
Electromyography 29
nerve conduction velocity 35
Entrapment neuropathy 31
Epidermal growth factor 182
Epithelial edge advancement 57
Equinus deformity 129f
Ertapenem 60
Erythema 51, 172
Erythrocyte sedimentation rate 73, 94
Escherichia coli 91, 170
Exostectomy 87, 166
Extensive necrosis 162
Fabry's disease 29
Fasciitis 169
Fasciotomy 162
Femoral neuropathy 31
Fever 172
diameter velocity 26
neuropathy, large 29, 37
Fibroblast growth factor 182
Fibula 11
Fissures 140, 145f
over bilateral hind foot 141f
Flat foot 14
Flexor digitorum
brevis 12
longus 11
Flexor hallucis
brevis 12
longus 11
Fluorodeoxyglucose 80
Folic acid 41
Foot 66, 78
amputations, levels of 167f
arches of 13, 14f
blood supply of 15f
bones of 10f
care 135, 145
clinical image of 68f
complex 9
extrinsic muscles of 11
functional segments of 11f
infection 114, 160
classification 108f
internal structure of sole of 12
muscles of 47f
nerve supply of 15f
perfusion, restoration of 111
plantar aspect of 145f
ulcer 19, 21, 25, 45f, 51, 133, 140
classification of 53, 54t
depth of 93
management of 53, 144
recurrent 50
width of 93
X-ray of 73
Forefoot 55
bones of 11
joint of 11
Fournier gangrene 169, 177
Fractures, acute neuropathic 86
Fungal nail 145f
Gabapentin 38
Gait 18, 37
cycle 18, 18f
Gamma aminobutyric acid 38
Gangrene 55, 162
Gastrocnemius 11
Gastrointestinal tract 25
Genitourinary tract 25
Ghost sign 79
Glucose 173
Glycemic control 40, 165
Gouty arthritis 85
Granulocyte colony-stimulating factor 182
Hallux valgus 129, 136
Hammer toes 30
disease, ischemic 128
rate 50
Heavy metal poisoning 29
Heel strike 18
Hemoglobin 5, 173
Hemostasis 161
Hindfoot 10, 11, 91
Charcot deformity 166t
forefoot angle 74
joint of 11
ulcer 93f
Hospital infection control committee 164, 176
Human immunodeficiency virus infection 29
Hydrogels 182
Hydrosurgery 182
Hyperalgesia 29
Hyperbaric oxygen therapy 181, 182
Hyperglycemia 5, 27
Hyperkeratosis 136
Hyperpigmentation 124f
Hypotension 172
Imipramine 38
Immune hypothesis 28
Immunoglobulin, intravenous 177
Immunosuppression 171
Impenem 60
acute 164
bacterial 56
grade of 163
mild 164
moderate 164
severe 164
treatment of 119
Infectious Disease Society of America 99
Inflammatory demyelinating polyneuropathy, chronic 36
like growth factor 28
neuritis 29
International Working Group of Diabetic Foot 34, 50, 108, 118
Interphalangeal joint 69, 71
Intertarsal joints 77f
Intrinsic muscles 12
Irrigation 161
Ischemia 108, 114, 162
Joint 11
axis 16f
destruction 77
dislocations 77
effusion 78f
mobility 19, 20
Large-fiber neuropathies 28fc
Larval therapy 182
Laser therapy 182
Leg, severe ischemia of 109
Levofloxacin 59, 60
Life-threatening sepsis 162, 166
Limb ischemia 165
Limb-threatening infections 166
Linezolid 60
Lipoprotein, low high-density 27
Liver 24
Local wound care 119
Longitudinal arch, medial 14
Lower leg, bones of 11
Macrostrain 152
Macular edema 24
Maggot therapy 182
Malaise 172
Marine-water infection 176b
Meary's angle 73, 74f, 76f, 82
Mechanical offloading 81
Medical management 81
Medical therapy 109
failure of 165
primarily 165
role of 165t
Meleney ulcer 169
Metabolic control 119
Metabolic hypothesis 27
Metatarsal fracture 85
Metatarsophalangeal joint 21, 69, 71, 73f, 77f, 86
dislocation of 76f
proximal 92f
Methicillin-resistant Staphylococcus aureus 58, 164, 169, 176
Methylene diphosphonate 99
Microalbuminuria 44
Microbiological control 58
Microcellular rubber 37
Microcirculatory disturbances 105
Microstrain 152
Microvascular hypothesis 28
Microvascular insufficiency 28
Midfoot 10, 55, 91
acute charcot 86
bones of 11
joint of 11
ulcer 94f, 124f
Minimal bone marrow edema 78f
Moisture balance 57
Monoclonal gammopathy 31
Monofilament 32b
method of 33
testing 32
types of 32f
Mononeuritis multiplex 26
Mononeuropathy 31
Morton's neuroma 30
Motion, ankle joint range of 17f
Motor neuropathy 3, 19, 26
Moxifloxacin 59
Multidisciplinary team 135
Multiple myeloma 29
Muscles 11
Myalgias 172
Myelination 25f
Myositis 169
Nail care 146
Naviculocuneiform joint 69
Necrotizing adipositis 169
Necrotizing fasciitis 162, 169, 170, 170t, 172b, 173t, 176, 176b, 177, 178b
clinical features in 172t
intraoperative features of 174b
pathological features of 174b
risk factors for 171b
surgical options in 174t
Necrotizing soft-tissue infection 160, 169, 172f, 175f
Negative pressure wound therapy 56, 150, 152, 153, 157, 157f, 166
biopsy 35
classification 26
study 35, 41
velocity 26, 36
growth factor 28
ischemia of 31
supply 14
Neuroischemic ulcer 48
over great toe 49f
Neurologic impairment score 36
Neurologic symptoms score 36
Neuropathic ulcer 46, 47f, 49t
Neuropathy 19, 35, 46, 56, 161
acute painful 29
asymmetric 31
chronic painful 29
diffuse 28
medical therapy for 42
Neurotrophic factors, deficiency of 28
Neurotrophic hypothesis 28
Neutrophilic leukocytosis 44
Newer techniques 35
Non-invasive tests 105
Non-neuropathic fractures 86
Nonproliferative diabetic retinopathy 24
Nonsteroidal anti-inflammatory drugs 31, 38, 171
Normocytic anemia 44
Nortriptyline 38
Nuclear medicine imaging 80
Nutritional supplements 181
Obesity 171
Opioids 39
Optimal antibiotic therapy 165
Osteoarthritis 30
Osteoarthropathy 161
Osteomyelitis 73f, 79, 80, 85, 91, 92, 92f, 93f, 98, 98t, 160
chronic 96f
diagnosis of 98
microbiology of 91
predictive of 93
Osteopenia 127f
Oxycodone 39
Oxygen saturation 50
Pacemaker 80
Pain 51
severe 66, 172
Painful diabetic neuropathy 37
peripheral 30t
treatment of 37, 40
Pamidronate 81
Paronychia 160
Patellar tendon bearing 62, 127
orthosis 128f
Pedal pulses intact 55
Penicillin 176
Peptide, calcitonin gene-related 69
Percutaneous electrical nerve stimulation 42
Percutaneous femoral angioplasty 113f
Perfusion extent depth infection sensation 163
Perineum 169, 177
Peripheral arterial disease 2, 4fc, 5, 6, 52, 104, 106f, 107, 114fc, 115, 161, 171
Peripheral nerves
classification of 25f
system 25
Peripheral neuropathy 3, 19, 24, 25, 41, 44, 69, 150, 161
diabetes-related 27
pathogenesis of 27
risk factors for 27
Peripheral sensory neuropathy 25
Peripheral vascular disease 19, 46, 104
Peroneal artery 15
Persistent soft tissue 165
Pes planus 14
Phalanges 10, 11
Phalanx 10
Photo plethysmography 106
Photoplethysmogram 105
Photoplethysmography 52
Phototherapy 182
Piperacillin 60, 176
Plantar aponeurosis 18
Plantar fascia 12, 12f
Plantar fasciitis 30
Plantar flexion 16
deformity correction 166
Plantar tissue thickness 21
Plaster of Paris 122
Platelet-derived growth factor 182
Podiatric procedures 166
Polyneuropathy, chronic inflammatory demyelinating 31
Positron emission tomography 80
Post-transmetatarsal amputation 45f
Pregnancy 171
magnitude of 20
reduces 57
relief of 119
repetition of 20
sores 151
Probe-to-bone test 93
positive 49
Procalcitonin 94
Protective sensation, loss of 4, 6, 32, 33, 50
Protein gene product 35
Pseudomonas aeruginosa 59, 91
palpable 55
volume recording 106
wave recording waveforms 105, 107
Quantitative autonomic function tests 36
Quantitative sensory tests 26, 36
Radiculopathy 30
Radionuclide scanning 98
Randomized controlled trial 38, 157
Ray amputation 167
Recent surgery 171
Reconstructive surgery 165
Rehabilitation 135
Renal failure 161
Renal insufficiency 50
Respiratory rate 50
Rocker foot deformity 72f
Salicylic acid 141f, 142f
Sanders and Frykberg classification 71, 72f, 83, 84, 86, 87
Saphenous nerve 14
Sclerosis 73f
Scrotum 169
Sensorimotor polyneuropathy 26
Sensory ataxia 30
Sensory modalities 26
Sensory nerve fibers 25
types of 26, 26t
Sensory neuropathy 19, 162
Septic arthritis 160
Serotonin norepinephrine reuptake inhibitors 38
Serotonin reuptake inhibitors 38
Serum inflammatory markers 94
Sesamoid bones 10, 11
Shockwave therapy 182
Silicone bunion shield 129
Silver dressings 181
Sinbad classification 55t
Single-photon emission computed tomography 99
Sinus tracts 79
Skin 12
blebs 172
graft 182
failed 151
pressure 105, 107
restoration of 119
ulceration 79
Sloughy tissue 57
neuropathy 28fc, 37
polyneuropathy 26
Sodium 173
Sodium-channel blockers 39
Soft tissue 21, 60
infections 169
classification of 169t
aureus 59, 91
epidermidis 91
Stasis ulcers 151
Stem cell therapy 182
Streptococcal toxic shock syndrome 178
Streptococcus species 59
Subchondral cysts 78f, 79
Subclinical neuropathy 26
Subcutaneous fat 79
Subtalar joint 17f, 69, 71
Subungual ulcer 58f
Sudomotor function devices 35
Sulfamethoxa 59
Sulfamethoxazole 176
Superficial fascia 12, 13
Superficial peroneal nerve 14
Sural nerve 14
Surgery 109
Surgical debridement 162, 176
Surgical management 161
Surgical preventive strategies 166
Surgical sharp debridement 57
Swelling 67
Syme amputation 133
Syme prosthesis 133
Systemic inflammation 164
Systemic inflammatory response syndrome 163
Systolic blood pressure 50
Tabes dorsalis 69
Tachycardia 172
Talus 10, 11
Tarsal joints 71
Tarsal tunnel syndrome 30
Tarsometatarsal amputation 167
Tarsometatarsal joint 69, 71, 77f, 83, 84
destruction of 127f
Tazobactam 60, 176
Technetium-99 m methylene diphosphonate 80
Tendo-Achilles 129
Tendons 11
Therapeutic intent, surgical management with 161
Thyroid function tests 24
Thyroid-stimulating hormone 36
Tibia 11
dry skin over shin of 145f
Tibial angioplasty 113f
Tibial artery, posterior 15
Tibial nerve, posterior 14
Tibialis posterior 11
Tissue debridement 57
amputation 167
brachial index 105, 106f, 107, 114
pressure 105, 106f, 108
Topical agents 39
Topical oxygen 182
Total contact cast 61f, 62, 81, 86, 121
role of 81
Total negative pressure technology 151
Toxic shock syndrome 171
Tramadol 39
Transcutaneous electrical nerve stimulation 40
Transcutaneous oximetry 52
Transcutaneous oxygen pressure 105, 108
Transmetatarsal amputation 112f, 167
stump ulcer 57f
Transverse arch 14
Transverse tarsal amputation 167
Trauma 151, 171
Tricyclic antidepressants 37
Trimethoprim 59, 176
Trophic ulcer 131
Truncal mononeuropathy 26
Ulcer 49, 55
chronic 161
deep 55, 92f
dressing 53
following trauma 50
formation 3
ischemic 48, 49t
non-healing 118
protection of 119
superficial 55
Vacuum-assisted closure 151, 155f
Vacuum-sealing technique 151
Vancomycin 60, 176
Varus deformity 127f, 132f
Vascular disease 19
Vascular endothelial growth factor 182
Vibration perception threshold measurement 34
Vibrio vulnificus 170, 176
Vitamin B12 36, 41
Waddling gait 30
Wagner–Meggitt classification 55t
Walking barefoot 161
Warm foot 30
White blood cell 94, 99, 173
Wifi classification system 108
Windlass mechanism 13
Wound 108, 114
abdominal 151
acute 151
care 165
chronic 151
necrotic 164
open 161
sternotomy 151
suction, sealed surface 151
X-ray, interpretation of 83
Zoledronic acid 81
Chapter Notes

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Introduction to Diabetic Foot CareCHAPTER 1

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“The foot is a masterpiece of engineering and a work of art”.
—Leonardo da Vinci2
Sandeep Kumar Agarwal,
Bharathi K,
Vasanth Mark Samuel,
Felix Jebasingh K,
Nihal Thomas
Diabetes mellitus is a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. It is well known that diabetes may lead to a number of micro- and macrovascular complications which include peripheral neuropathy, peripheral vascular disease, increased risk of foot infection and delayed wound healing.1
Out of all the complications, diabetic foot disease (DFD) can be considered as one of the most devastating and demoralizing complications of diabetes. The Diabetic foot is defined as a group of disorders wherein neuropathy, ischemia or infection may lead to tissue breakdown and a potential to progress toward amputation. The lifetime risk for the development of a diabetic foot ulcer (DFU) in patients with diabetes may range from 15 to 25%, and this is known to precede amputation in 85% of cases.2,3 The rate of lower limb amputation in patients with DM is 15 times higher than in patients without diabetes and approximately 50–70% of all lower limb amputations are due to DFU.4 Every 20 seconds a lower limb is lost due to diabetes and it is the most common cause of non-traumatic lower limb amputation.5 It may severely impair the quality of life of patients by affecting productivity, social participation, and livelihood. These amputations also precipitate an increase in mortality rate. However, there are a number of preventable causes for amputation particularly in low socioeconmic societies, such as a lack of sanitation and hygiene, socio-cultural practices such as barefoot walking inside the house and at religious places, lack of awareness on the use of proper footwear and a dearth of foot care clinics which may add to the burden of foot disease related to diabetes mellitus.
DFD includes several pathologies, particularly diabetic peripheral neuropathy (DPN), peripheral arterial disease (PAD), and infections (Flowchart 1). DPN results in sensory, motor and autonomic nerve dysfunction leading to DFU. When screening, almost all patients with diabetes who are undergoing foot-related surgical procedures, a majority are found to have neuropathy.63
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FLOWCHART 1: Risk factors and mechanism for foot ulcer and amputation.
Peripheral neuropathy is associated with high rates of skin breakdown and neuropathic fractures due to the inability to perceive pain sensation. The inciting trauma may include ill-fitting shoes or minor sprains and strains. Without protective sensation, a patient with peripheral neuropathy lacks the physical symptoms that would alert healthy individuals to examine their feet, thereby increasing the extent of skin damage, prior to their presentation for treatment. Patients with moderate to severe sensory loss are shown to have a seven-time higher risk of developing a first DFU when compared to patients with preserved sensation.7
Autonomic dysfunction, as a result of neuropathy, may also contribute to ulcer formation. It affects both physiologic secretions and the arterio-venous systems leading to dry and fragile skin. This in turn increases the risk of cracks, fissures and skin breakdown, and thereafter, the risk of infection. Motor neuropathy may lead to structural changes to the foot and these changes are partly due to muscular weakness and imbalance caused by intrinsic atrophy manifesting as hammer toes, mallet toe, claw toes, a prominent metatarsal head and other deformities. Such deformities, in turn change pressure patterns on the foot resulting in certain areas becoming more susceptible to trauma or ulceration.
Charcot neuropathic osteoarthropathy (CN) or Charcot foot is also a part of DFD that may affect the bones, joints, and soft tissues of the foot and ankle, characterized by inflammation in its early phase. Diabetes-related Charcot's arthropathy has a reported prevalence between 0.08 and 13%.8 Patients with diabetic foot are also 4more likely to present with other diabetes-related complications inclusive of nephropathy, retinopathy, ischemic heart disease and cerebrovascular disease which further aggravate DFD. A combination of neuropathy, abnormal load bearing by the foot, repeated microtrauma, and metabolic abnormalities of bone leads to osteolysis, fractures, dislocation and deformities.
Diagnosing DFD involves a need for a thorough foot examination, which aids in the detection of disease at an early stage. Screening for peripheral neuropathy and PAD may help identify patients at risk of foot ulcers. A history of ulcers or amputations and poor glycemic control, increases the risk further. Examination of the feet at each follow-up visit for any active disease such as ulceration or gangrene is extremely crucial. Clinicians should look for lesions such as cracks, skin fissures, deformed nails, fungal infections, macerated web spaces, calluses and deformities such as claw toes, hammer toes and pes cavus which increase the risk of ulceration. It is advisable to assess the temperature of the feet with the dorsum of the hand. A cold foot might suggest ischemia, and increased warmth with redness and swelling might suggest inflammation such as cellulitis or an acute Charcot foot.
Screening should be done to identify patients with a loss of protective sensation (LOPS) in the feet. Most guidelines recommend the 10 g monofilament for neuropathy assessment in people with diabetes. This monofilament exerts a 10 g buckling force when it bends. An inability to sense a 10 g pressure is consistent with LOPS. The test may be combined with another test to screen for neuropathy, such as a biothesiometer or a graduated tuning fork (Rydel Seiffer) to assess the vibration perception threshold.
One should ask for a history of intermittent claudication and rest pain, which may suggest PAD. The ankle brachial index is an easy adjunct bedside measure to diagnose PAD (Flowchart 2). It is the ratio of the highest systolic blood pressure at the ankle (dorsalis pedis artery or posterior tibial artery) to the systolic blood pressure at the arm, and is measured using a Doppler device.
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FLOWCHART 2: The evaluation of peripheral artery disease in patients with diabetes.
People with diabetes can often have falsely raised ankle brachial index levels as a result of poor compressibility from calcified arteries. Availability of equipment, time constraints, and lack of training are also major barriers to ankle brachial index testing in the primary care setting.
Peripheral arterial disease is frequently found with neuropathy, in the diabetic patient and can contribute to foot complications. Approximately 50% of patients with DFD are found to have some degree of PAD. Compared to patients with diabetes and Charcot neuropathy, patients with DFUs are significantly more likely to have PAD, critical limb ischemia and more often require revascularization (Flowchart 2). Endothelial damage and vessel sclerosis of both large and small vessels leads to decreased peripheral perfusion. Hence, patients are at an increased risk for ulceration and leads to impaired wound-healing and infection-fighting abilities.
Patients with diabetes have an impaired ability to mount an inflammatory response to infection (immunopathy). Impaired neutrophil function, chemotaxis, phagocytosis, as well as a decreased T-cell response have been found in patients with diabetes versus those without diabetes. Hyperglycemia could be one of the etiological factors behind this, which impairs host defenses at the cellular level, affecting leukocytes, macrophages and other cell types. PAD and immunopathy do not directly cause ulceration; however, these patient factors can increase the risk of diabetic foot complications in those with diabetic neuropathy.
Based on the initial assessment, patients may be categorized as having a low, moderate, or high risk of diabetic foot (Fig. 1). Low risk indicates the presence of callosities alone; medium risk: The presence of deformity, LOPS, or PAD; high risk includes a previous history of amputation or ulceration along with the presence of any two of the following: LOPS, PAD, and lesions or deformities.9
The suggested frequency for follow-up is based on the level of risk. In the low risk state, an annual foot assessment should be performed as they could progress to a moderate or high risk state. Emphasis should be on daily foot inspection and monitoring glycemic control. Increased frequency of follow-up is advised in patients at moderate or high risk, such as those with a foot deformity or with a diagnosis of peripheral neuropathy or PAD at initial assessment. Repeat testing for neuropathy is not necessary if diagnosed previously. A quick inspection for a breach in skin integrity or ulceration should suffice. Patients with asymptomatic PAD may be followed up in primary care centers and managed as in guidelines for PAD. Patients with calluses and deformed toe nails should be referred to preventive podiatry services for basic nail and skin care, including debridement of calluses. A timely referral to the foot protection services for control of risk factors in patients with diabetes prevents infection, gangrene, amputation, or death and reduces hospital admissions.
Early and good glycemic control is effective in preventing peripheral neuropathy. Optimal blood glucose and glycated hemoglobin (HbA1c) targets should be discussed with patients and monitored as per the standard guidelines for diabetes care to prevent or slow the progression of peripheral neuropathy.6
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FIG. 1: Assessment of risk of the diabetic foot.
People with diabetes or their caregivers, or both should be educated on the importance of blood glucose control and modifiable cardiovascular risk factors such as healthy eating habits and lifestyle patterns, regular physical exercise, maintenance of ideal body weight and cessation of smoking and alcohol. While offering modifications in lifestyle, one should consider the patient's cultural as well as religious beliefs and also the social and family support available.
Evidence for the effectiveness of patient education on foot care is lacking. Previously done randomized controlled trials have shown that brief foot care education alone does have a positive influence on patient knowledge and behavior on the short term, but it is ineffective in preventing DFUs. However, education in a structured, organized, and repetitive manner, combined with preventive interventions may prevent foot related problems.
Another less emphasized and ignored aspect of footcare is the usage of appropriate footwear. The sole should be neither too hard nor too soft with a Shore value between 8 and 15 A. Commercially available footwear are often occlusive and causing excessive sweating, thereby precipitating fungal infections, particularly in tropical countries. Bare foot walking is a major risk factor for a succeeding ulcer, especially in patients with neuropathy. Moreover, barefoot walking is rather common amongst people in the many indigenous populations. Patient compliance with regards to the prescribed footwear is usually poor, particularly at home and hence this should be reinforced. Patients with plantar ulcers at the forefoot or heel may be offered offloading footwear to allow ulcer healing and prevent recurrence.7
Patients with a life- or limb-threatening problem such as foot ulceration with fever or any signs of sepsis; ulceration with limb ischemia; gangrene, or a suspected deep seated soft tissue or bone infection indicated by either a grossly swollen foot with shiny skin and patches of discoloration or a gritty feel to the bone during a probe to bone test in an open wound should be immediately referred to a specialized diabetic foot center; which are frequently lacking.
Poor outcomes of foot complications in resource poor settings may include the shortage of trained healthcare workers for diabetes care, lack of awareness of footcare among patients and healthcare providers, non-existent podiatry services, shortage of medications and dressing supply, long distances for patients to travel to the clinic, delay by patients in seeking timely medical care or by untrained healthcare providers in referring patients with serious complications for a specialist opinion, lack of the concept of a team approach, absence of training programs for healthcare professionals and finally, a lack of surveillance activities.
Most ulcers may be prevented with appropriate foot care and screening for risk factors for “the foot at risk”, for complications. A good understanding of the various predisposing risk factors, would help in both prevention and treatment of this devastating medical condition.
Therefore, this book aims at providing a comprehensive approach toward the management of diabetic foot amongst those with limited health care resources through an integrated foot care program.
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  1. Amin N, Doupis J. Diabetic foot disease: From the evaluation of the “foot at risk” to the novel diabetic ulcer treatment modalities. World J Diabetes. 2016;7(7):153–64.
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