Diabetic Neuropathy


Introduction[edit | edit source]

Diabetic neuropathy is dysfunction and damage in the peripheral nerves in people with diabetes[1]. Neuropathies are characterized by a progressive loss of nerve fibre function[2]. Diabetic neuropathy is a common complication of Diabetes Mellitus (DM), estimated to affect up to 51% of patients with both type 1 and type 2 DM[3][4]. The clinical presentation of diabetic neuropathy varies, from asymptomatic to severe neuropathic pain and numbness[3]. Diabetic neuropathy is associated with increased risk of foot ulcers, lower limb amputation and mortality[5][6].

Clinically Relevant Anatomy[edit | edit source]

The peripheral nervous system refers to the components of the nervous system outside of the brain and spinal cord. The nerve roots exit the spinal cord and then branch out into smaller peripheral nerves. The peripheral nerves consist of motor and sensory fibers[7].

In diabetic neuropathy, there is degeneration in the type, severity, and distribution of these receptors, nerve fibers, or neurons, with the degeneration beginning distally and symmetrically, and spreading proximally[8].

Mechanism of Injury / Pathological Process[edit | edit source]

The pathological process of diabetic neuropathy is not completely understood, and is likely multifactoral[9]. Research suggests neuronal inflammation, oxidative stress, mitochondrial dysfunction and cell death is caused by hyperglycaemia, dyslipidaemia and microvascular disease[6].

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Risk Factors[10][edit | edit source]

Clinical Presentation[edit | edit source]

More than half of the cases are distal symmetric polyneuropathy[12]. Asymmetrical or focal syndromes, such as carpal tunnel syndrome[13] (14-30%), radiculopathies/plexopathies and cranial neuropathies, account for the rest[14].

The most common symptoms are[15]:

  • Numbness in the hands or feet, often on both sides, described as a stocking-and-glove distribution
  • Tingling/"pins and needles" or burning sensation in the feet
  • Pain in the hands, feet, or legs
  • Dry or cracked skin or calluses on the feet.
  • Distal, proximal or more focal weakness, including foot drop or frequent tripping.

Diagnostic Procedures[edit | edit source]

  • Subjective history of symptoms, recent foot trauma and previous ulcers or wounds[16].
  • Physical examination of skin condition, foot anatomy, and vascular perfusion[16].
  • Testing includes assessment of gross light touch and pinprick sensation, using simple hand held devices (e.g. cotton wool, stick pins or monofilament)[8].
  • Vibratory sense in the feet is tested with a 128-Hz tuning fork placed at the base of the great toenail[17].
  • Deep tendon reflexes are commonly hypoactive or absent[18].
  • Nerve conduction studies or needle electromyogram[19].

Classification[edit | edit source]

Diabetic neuropathy can be classified into 4 subgroups:[20]

  • Proximal neuropathy/ diabetic amyotrophy.
  • Peripheral neuropathy / diabetic nerve pain / distal polyneuropathy.
  • Autonomic neuropathy.
  • Focal neuropathy / mononeuropathy.

Staging[edit | edit source]

A common staging scale of diabetic neuropathy is as follows: [21]

  • N0 - No neuropathy.
  • N1a - Signs but no symptoms of neuropathy.
  • N2a - Symptomatic mild diabetic polyneuropathy; sensory, motor, or autonomic symptoms; patient able to heel walk.
  • N2b - Severe symptomatic diabetic polyneuropathy, and patient unable to heel walk.
  • N3 - Disabling diabetic polyneuropathy.

Medical Management / Interventions[edit | edit source]

Medical management starts with 0ptimized glycemic control (mainly for type 1 DM) and lifestyle interventions[22]. Lifestyle intervention includes physical exercise and weight loss.

Tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors (e.g. duloxetine) and anticonvulsants (e.g. pregabalin and gabapentin) are commonly prescribed treatments for neuropathic pain[23]. At present, there are no universally accepted disease modifying medicines, but this is currently being researched and developed[24].

Moreover, multidisciplinary team management is required for the prevention and management of diabetic foot complications[6].

Physiotherapy Management and Exercise[edit | edit source]

Research has shown that strength training can moderately improve muscle function, reduce neuropathic pain and help control blood sugar levels for people with diabetic neuropathy[25]. Therefore, exercise can help to improve quality of life for this patient group[26]. Diabetic clients must take precautions, including monitoring their blood sugar levels during exercise and snacking beforehand to prevent major fluctuations[27].

Specific exercise programs should include[25][edit | edit source]

  • Flexibility (progressive stretching and self stretches).
  • Muscle strengthening (using a variety of modes as appropriate eg isometric, graded weight progression, open and close chain)[28].
  • Aerobic activity.
  • Posture and balance training (for falls prevention and stability)[29].
  • Gait (can improve proprioception and gait pattern in patients with diabetic neuropathy)[30][31].
  • Splinting for mononeuropathies eg. carpal tunnel or for muscle weakness e.g. ankle foot orthoses.[25]

The youtube below shows some good exercises that a physiotherapist can employ to help manage the symptoms of diabetic neuropathy:

[32]

A 2014 review found that the biggest consequence of diabetic neuropathy was a increase in risk of falls [33]. Therefore balance and falls prevention programs and training, in the senior diabetic clientele in particular, is very beneficial.

[34]

Physiotherapy Management of Pain in Diabetic Neuropathy[edit | edit source]

see also Nerve Injury Rehabilitation Physiotherapy

Evidence has been provided for:

  1. Transcutaneous Nerve Stimulation (TENS)[35].
  2. Massage[36].
  3. Static magnetic field therapy[37].
  4. Low-intensity laser therapy[38].
  5. Monochromatic infrared light[39].
  6. Acupuncture[40].

Differential Diagnosis[edit | edit source]

Other possible causes of neuropathy include[41]:

References[edit | edit source]

  1. Rosenberger DC, Blechschmidt V, Timmerman H, Wolff A, Treede RD. Challenges of neuropathic pain: focus on diabetic neuropathy. J Neural Transm (Vienna). 2020 Apr;127(4):589-624.
  2. Boulton AJ, Malik RA. Diabetic neuropathy. Med Clin North Am. 1998;82(4):909-29
  3. 3.0 3.1 Hicks CW, Selvin E. Epidemiology of Peripheral Neuropathy and Lower Extremity Disease in Diabetes. Curr Diab Rep. 2019 Aug 27;19(10):86.
  4. Dyck PJ, Kratz KM, Karnes JL, Litchy WJ, Klein R, Pach JM, et al. The prevalence by staged severity of various types of diabetic neuropathy, retinopathy, and nephropathy in a population-based cohort: the Rochester Diabetic Neuropathy Study. Neurology. 1993;43(4):817-24
  5. Malik RA. Which Test for Diagnosing Early Human Diabetic Neuropathy? Diabetes. 2014 Jul;63(7):2206-8
  6. 6.0 6.1 6.2 Sloan G, Selvarajah D, Tesfaye S. Pathogenesis, diagnosis and clinical management of diabetic sensorimotor peripheral neuropathy. Nat Rev Endocrinol. 2021 Jul;17(7):400-420.
  7. Spine-Health. Peripheral Nervous System Anatomy. Available from: https://www.spine-health.com/conditions/spine-anatomy/anatomy-nerve-pain (Accessed 06/07/22).
  8. 8.0 8.1 Dyck PJ, Herrmann DN, Staff NP, Dyck PJ. Assessing decreased sensation and increased sensory phenomena in diabetic polyneuropathies. Diabetes. 2013 Nov;62(11):3677-86
  9. Zochodne DW. Diabetic polyneuropathy: an update. Curr Opin Neurol. 2008;21(5):527-33
  10. Kartha C, Ramachandran S, Pillai RM, editors. Mechanisms of Vascular Defects in Diabetes Mellitus. Springer. 2017. p.163
  11. Kote GS, Bhat AJ, Thajuddeen K, Ismail MH, Gupta A.Peripheral Insensate Neuropathy-Is Height a Risk Factor? J Clin Diagn Res. 2013; 7(2): 296–301
  12. Bodman MA, Varacallo M. Peripheral Diabetic Neuropathy. 2022 May 1. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan
  13. Singh R, Gamble G, Cundy T. Lifetime risk of symptomatic carpal tunnel syndrome in Type 1 diabetes. Diabet Med. 2005;22(5):625-30
  14. Shaw JE, Zimmet PZ. The epidemiology of diabetic neuropathy. Diabetes Reviews. 1999;7:245-52
  15. Cedars Sinai. Diabetic Neuropathy. Available from: https://www.cedars-sinai.org/health-library/diseases-and-conditions/d/diabetic-neuropathy.html (Accessed 09/07/2022)
  16. 16.0 16.1 Bandyk DF. The diabetic foot: Pathophysiology, evaluation, and treatment. Semin Vasc Surg. 2018 Jun-Dec;31(2-4):43-48
  17. American Diabetes Association. Vibration Testing Detects Diabetic Peripheral Neuropathy Earlier than the 10-g Monofilament. Available from: https://professional.diabetes.org/abstract/vibration-testing-detects-diabetic-peripheral-neuropathy-earlier-10-g-monofilament (Accessed 09/07/2022)
  18. Medscape. How are deep tendon reflexes assessed in diabetic neuropathy? Available from https://www.medscape.com/answers/1170337-4949/how-are-deep-tendon-reflexes-assessed-in-diabetic-neuropathy (Accessed 09/07/2022)
  19. Yang Z, Zhang Y, Chen R, Huang Y, Ji L, Sun F, Hong T, Zhan S. Simple tests to screen for diabetic peripheral neuropathy. Cochrane Database Syst Rev. 2018 Jul 30;2018(7)
  20. Endocrine Web. Types of Diabetic Neuropathy. Available from: https://www.endocrineweb.com/guides/diabetic-neuropathy/types-diabetic-neuropathy (Accessed 07/07/2022)
  21. Dianna Quan,Helen C Lin ; Diabetic Neuropathy Clinical Presentation. Available from: http://emedicine.medscape.com/article/1170337-clinical#a0256 (Accessed 26 May 2020)
  22. Cernea S, Raz I. Management of diabetic neuropathy. Metabolism. 2021 Oct;123:154867.
  23. Callaghan BC, Gallagher G, Fridman V, Feldman EL. Diabetic neuropathy: what does the future hold? Diabetologia. 2020 May;63(5):891-897.
  24. Røikjer J, Mørch CD, Ejskjaer N. Diabetic Peripheral Neuropathy: Diagnosis and Treatment. Curr Drug Saf. 2021;16(1):2-16.
  25. 25.0 25.1 25.2 The Foundation for Peripheral Neuropathy. Exercise and physical therapy for neuropathy. Available from: https://www.foundationforpn.org/living-well/lifestyle/exercise-and-physical-therapy/ (Accessed 10/07/2022)
  26. Jahantigh Akbari N, Hosseinifar M, Naimi SS, Mikaili S, Rahbar S. The efficacy of physiotherapy interventions in mitigating the symptoms and complications of diabetic peripheral neuropathy: A systematic review. J Diabetes Metab Disord. 2020 Oct 12;19(2):1995-2004.
  27. Diabetes.co.uk. Exercise for Diabetics. Available from: https://www.diabetes.co.uk/exercise-for-diabetics.html (Accessed 10/07/2022)
  28. Win MMTM, Fukai K, Nyunt HH, Linn KZ. Hand and foot exercises for diabetic peripheral neuropathy: A randomized controlled trial. Nurs Health Sci. 2020 Jun;22(2):416-426.
  29. Thukral N, Kaur J, Malik M. A Systematic Review and Meta-analysis on Efficacy of Exercise on Posture and Balance in Patients Suffering from Diabetic Neuropathy. Curr Diabetes Rev. 2021;17(3):332-344
  30. The Daily Star. Physiotherapy for diabetic neuropathy. Available from: https://www.thedailystar.net/health/how-to-prevent-diabetic-neuropathy-by-physiotherapy-1512505 (Accessed 10 April 2019)
  31. Ahmad I, Verma S, Noohu MM, Shareef MY, Hussain ME. Sensorimotor and gait training improves proprioception, nerve function, and muscular activation in patients with diabetic peripheral neuropathy: a randomized control trial. J Musculoskelet Neuronal Interact. 2020 Jun 1;20(2):234-248.
  32. Physical Therapy Video. Peripheral neuropathy relief in the feet and legs. Available from: https://www.youtube.com/watch?v=n23mUQexmKw (accessed 9 March 2019)
  33. Pan X, Bai JJ. Balance training in the intervention of fall risk in elderly with diabetic peripheral neuropathy: A review. International Journal of Nursing Sciences. 2014;1(4):441-5.
  34. Physical Therapy Video. 7 balance exercises for seniors fall prevention. Available from: https://www.youtube.com/watch?v=BNC4bi3Ucac (accessed 9 March 2019)
  35. Kumar SP, Adhikari P, Jeganathan PS, D'Souza SC. PHYSIOTHERAPY MANAGEMENT OF PAINFUL DIABETIC PERIPHERAL NEUROPATHY: A CRITICAL REVIEW OF TREATMENT METHODS FOR CLINICAL DECISION MAKING IN PRACTICE AND RESEARCH. International Journal of Current Research and Review. 2010. 02(09):29-39
  36. Gok Metin Z, Arikan Donmez A, Izgu N, Ozdemir L, Arslan IE. Aromatherapy Massage for Neuropathic Pain and Quality of Life in Diabetic Patients. J Nurs Scholarsh. 2017 Jul;49(4):379-388.
  37. Weintraub MI, Wolfe GI, Barohn RA, Cole SP, Parry GJ, Hayat G, Cohen JA, Page JC, Bromberg MB, Schwartz SL; Magnetic Research Group. Static magnetic field therapy for symptomatic diabetic neuropathy: a randomized, double-blind, placebo-controlled trial. Arch Phys Med Rehabil. 2003 May;84(5):736-46
  38. Cotler HB, Chow RT, Hamblin MR, Carroll J. The Use of Low Level Laser Therapy (LLLT) For Musculoskeletal Pain. MOJ Orthop Rheumatol. 2015;2(5):00068
  39. Robinson CC, Klahr PDS, Stein C, Falavigna M, Sbruzzi G, Plentz RDM. Effects of monochromatic infrared phototherapy in patients with diabetic peripheral neuropathy: a systematic review and meta-analysis of randomized controlled trials. Braz J Phys Ther. 2017 Jul-Aug;21(4):233-243
  40. Dimitrova A, Murchison C, Oken B. Acupuncture for the Treatment of Peripheral Neuropathy: A Systematic Review and Meta-Analysis. J Altern Complement Med. 2017 Mar;23(3):164-179.
  41. Cleveland Clinic. Neuropathy. Available from: https://my.clevelandclinic.org/health/diseases/14737-neuropathy (Accessed 07/07/22)