DERMATOLOGY PRACTICAL & CONCEPTUAL www.derm101.com Review | Dermatol Pract Concept 2012;3(1):2 3 Case report The 57-year-old woman pictured (Figure 1) has had epi- sodic pruritus of the mid-back for six years. She denied any apparent cause for the pruritus. At times there was an accompanying sensation of “pins and needles.” She also complained of heightened sensitivity in the area, which she noticed when putting on clothes or rubbing her back against the bed. She located the affected area medial to the left scapula. She could not identify anything that improved or worsened the symptoms. On examination, there was a hyperpigmented patch medial to the left scapula within the dermatomes of T2-T6. The patient had hyperesthesia to light touch in this area. There were no dermatitis, excoriations, or appreciable tissue texture changes, warmth, or edema. Comment For centuries people have complained about an itch, just between the shoulder blades, that is out of reach to scratch. For some, the itch can become so persistent, so maddening that finding a way to scratch is all consuming. The back- scratcher is such a primitive tool that even apes have been observed making them from tree branches. Elaborate back- scratchers have been fashioned from everything from whale- Notalgia paresthetica: the unreachable itch Carolyn Ellis, D.O.1 1 Largo Medical Center, Largo, Florida Key words: notalgia paresthetica, pruritus, cutaneous neuropathy, neuropathic itch, backscratcher Citation: Ellis C. Notalgia paresthetica: the unreachable itch. Dermatol Pract Conc. 2013;3(1):2. http://dx.doi.org/10.5826/dpc.0301a02. Received: September 5, 2012; Accepted: December 3, 2012; Published: January 31, 2013 Copyright: ©2013 Ellis. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: None. Competing interests: The author has no conflicts of interest to report. No sources of funding were used to assist in the preparation of this review. This literature review is an original contribution. Corresponding author: Carolyn Ellis, D.O., 500 Belcher Rd S, #194, Largo, FL 33771.Tel. 207.542.9506. Email: caroly.litty@gmail.com. Background: Notalgia paresthetica (NP) is a very common, under-recognized condition characterized by pruritus in a unilateral, dermatomal distribution in the mid-back. Chronic pruritus is sometimes accompanied by pain, paresthesias, or altered sensation to touch. Objectives: To review the current literature with regards to the cause of NP and its most appropriate treatment. Methods: Comprehensive literature review using PubMed to inspect the available data on NP. Results: The most likely cause of NP is cutaneous nerve damage. Many therapies have been tried in the treatment of NP, mostly in small case studies. Conclusions: The published cases and studies suggest symptoms of NP are due to a cutaneous sensory neuropathy. Treatments addressing the condition as such are more successful than traditional itch therapies. In many cases, a simple explanation for the persistent pruritus is satisfactory for patients. For very distressing cases, therapy should address the condition as a benign sensory neuropathy. Fur- ther studies are needed to evaluate which treatments have the greatest potential for providing symp- tom relief. ABSTRACT bone to tortoiseshell and have been designed by diverse cultures throughout time. We postulate that notalgia pares- thetica (NP) was the stimulus leading to the invention of the backscratcher, perhaps by our primate ancestors. Another possible explanation could be that the backscratcher or simi- lar instrument is not the treatment of NP but its cause. Itch can lead to scratching and rubbing either with an instrument or against a wall, which leads to post-inflammatory hyper- pigmentation and the findings that we call NP. NP is a common dermatologic complaint characterized by unilateral pruritus medial or inferior to the scapula. The condition was first described in 1934 by Astwazaturow, though the complaint of a chronically itchy back has likely plagued people since the beginning of time. NP is typically confined to the dermatomes of T2-T6 and may have accom- panying pain, paresthesia, numbness, or hyperesthesia. A patch of lichenification or post-inflammatory hyperpigmen- tation is the result of chronic scratching [1-3]. It may be more prevalent in middle-age women and often lasts for years [4]. The cause of NP is unclear. Several possible etiologies have been proposed, but it is generally believed that NP is a sensory neuropathy. A small study by Springall and col- leagues suggested a proliferation of cutaneous nerves in NP 4 Review | Dermatol Pract Concept 2012;3(1):2 Figure 1. (A) The symptomatic area medial to the patient’s left scapula is visible as a hyperpigmented patch. (B) The hyperpigmented patch is highlighted on the patient’s mid-back. [Copyright: ©2013 Ellis.] lesions [5]. This finding was not confirmed in any of the 14 patients Savk et al biopsied; none of the tissue samples showed an increase in dermal innervation compared with controls [6]. Most evidence suggests NP is the result of dam- age to the cutaneous branches of the posterior divisions of the spinal nerves. This can occur either by impingement from degenerative changes in the spine or spasms in the paraspinal musculature. Pain, paresthesia, and numbness are more com- monly thought of as neurological findings, but pruritus is an often-unrecognized symptom of nerve damage. Muscle spasms or fibrous bands may compress cutane- ous nerves and cause symptoms. Massey and Pleet used elec- tromyography to detect paraspinal denervation at T2-T6, corresponding to symptoms of NP in 7 out of 9 patients. They suggest the sensory nerve branches at T2-T6 are sus- ceptible to minor trauma because of how they pierce the multifidus spinae muscle [7]. The dorsal nerve roots exit the fascia of the multifidus spinae at a right angle en route to the epidermis; as a result they may be more exposed and prone to injury than in other areas of the back [7, 8]. These nerves can also be entrapped as they exit the spine through the vertebral foramen. A study by Savk and Savk of 43 patients with NP showed over 60% had radiographic findings of degenerative vertebral changes or herniated discs in areas that corresponded to the dermatomal distribution of their symptoms [4]. Several other studies have similarly shown an association between NP and significant spinal pathology [2,3,9]. The diagnosis is made clinically on the basis of history. Often, there are few if any signs of the disease; in some cases there may be localized hyperpigmentation or sensory find- ings in the infrascapular area. Spinal imaging is not neces- sary unless the patient has other neurological or musculo- skeletal symptoms. Differential diagnosis should include tinea versicolor, contact dermatitis, parapsoriasis, neuroder- matitis, and macular amyloidosis. Biopsy of NP may show signs of post-inflammatory hyperpigmentation, mild hyper- keratosis, and mild inflammatory infiltrate of the papillary dermis with dermal melanophages [2,3,6]. Some studies show no evidence of amyloid deposition in NP [2,6], while others do report sparse amyloid detected in dermal papillae [3,10]. This type of cutaneous amyloid is the result of dam- age to keratinocytes from chronic friction (scratching). It is therefore not surprising to see amyloid deposits in pruritic NP lesions that have been present for years. However, the presence of amyloid can make the distinction from macu- lar amyloidosis difficult, as there is considerable overlap of these two entities [10]. Typical itch treatments such as antihistamines or topical steroids do not address the neuropathic itch of NP [3]. Other treatments that have been tried include topical capsaicin [11], cutaneous botulinum toxin type A injections [12], local Review | Dermatol Pract Concept 2012;3(1):2 5 nerve block [13], gabapentin [14], oxcarbazepine [15], and surgical decompression of the nerve [8]. These therapies have shown varied improvement of symptoms, may be expensive, invasive or require continued long-term use, and in some cases have undesirable side effects (Table 1). Recent studies have looked at several non-pharmacolog- ical, non-surgical therapies to address the neuro-musculo- skeletal pathology presumed to cause NP (Table 1). Savk and Savk showed that transcutaneous electrical nerve stimulation yielded statistically significant improve- ment in the symptoms of 15 NP patients with correspond- ing radiographic findings. From an initial pruritus of 10/10, there was a decrease in pruritus to a mean 6.8/10 after ten sessions over two weeks [9]. A case study using exercises to strengthen postural mus- cles and extend the spine, thereby reducing the angle of the cutaneous nerves as they pass through the muscles and the transverse processes, completely eliminated pruritus in two women with NP [16]. Acupuncture also appears promising for relief of NP. A study of 16 patients with neurogenic pruritus, seven of which had presentations consistent with NP, illustrated complete relief of pruritus in 75% after 2-6 treatments with deep intramuscular stimulation acupuncture. Recurrence of symptoms did occur after 1-12 months without therapy in 37%, necessitating further treatment [17]. Osteopathic manipulative treatment (OMT) relieved pruritus in a middle-aged woman who developed NP follow- ing a motor vehicle accident. Soft tissue techniques applied to the affected upper thoracic and scapular regions improved the patient’s pain and itching [18]. This was only a single case study, but if proven effective it may be an easy way for osteopathic dermatologists comfortable with OMT to treat these patients. TABLE 1. Treatment options for notalgia paresthetica Treatments Description Efficacy Capsaicin [11] 0.025% cream to affected areas 5 x day for 1 week, then 3 x day for 5 weeks 70% had improvement, but symp- toms returned within a month of stopping treatment Botulism toxin type A [12] 4 units per superficial injection, spaced 2 cm apart throughout af- fected area Resolution of symptoms for over 18 months observed in one patient Nerve block [13] 5 mL bupivacaine 0.75% with 40 mg methylprednisolone acetate Resolution of symptoms for at least 12 months in one patient Gabapentin [14] Initial dose of 300 mg at bedtime, increased to 600 mg Resolution in one patient while on medication. Symptoms returned fully when medication stopped Oxcarbazepine [15] Initial dose of 300 mg twice daily. Increased to 600 or 900 mg to achieve adequate relief Improvement, no resolution, in four patients Surgery [8] Surgical decompression of cutane- ous nerve Resolution of symptoms observed in one patient Transcutaneous Electrical Nerve Stimulation [9] 5 20-minute sessions/week x 2 weeks, 50-100 Hz with a 40-75 μs pulse width Improvement of symptoms, no reso- lution, in 15 patients Exercise [16] Strengthening of rhomboid and la- tissimus dorsi muscles, stretching of pectoral muscles daily for one week Resolution of symptoms in two patients Acupuncture [17] Deep intramuscular stimulation to paraspinal muscles in affected area every 1-2 weeks until relief Partial to complete resolution after 2-6 treatments, but relapse of symp- toms in 1-12 months, observed in 16 patients Osteopathic Manipulative Treatment [18] Muscle energy, soft tissue, inhibi- tion, fascia release Improvement of symptoms observed in one patient 6 Review | Dermatol Pract Concept 2012;3(1):2 All of these modalities warrant further investigation of their usefulness for the treatment of NP and other types of neurogenic pruritus. Patients often get some relief simply by learning the pruritus they are experiencing has a biologi- cal cause and a name. In persistent cases that interfere with quality of life, say if your patient owns multiple, strategi- cally located back scratchers, some of these therapies may be worth trying. And while scratching to excess with a large salad fork is not recommended, for more mild symptoms, the timeless phrase, “I’ll scratch your back if you’ll scratch mine” is fitting. And the market for back scratchers is as strong as ever. Conclusion Take home messages about notalgia paresthetica: • NP is a unilateral pruritus located medial or inferior to the scapula in the T2-T6 dermatomal region. • NP is most often seen in middle-aged women and can last for months or years. • It may be accompanied by pain, paresthesias, numbness, or hypersensitivity. • Symptoms are most likely caused by impingement of nerves as they exit the spinal column or traverse through muscles of the back. It is sometimes seen in association with herniated discs or degenerative disc disease. • Traditional itch treatments (antihistamines, topical ste- roids) fail because they do not address the neuropathy. • Many modalities have been used to treat NP with varying success. The most important point to keep in mind is this is a harmless condition, which often does not warrant the potential side effects or risks of many treatments. • Educating patients about the cause and course of the con- dition can be the most important aspect of treatment. Acknowledgements: The author would like to acknowledge the invaluable contributions of David Elpern, M.D. This paper was written during a dermatology clerkship in his office. His input and help with editing is greatly appreciated References 1. Massey EW, Pleet AB. Localized pruritus–notalgia paresthetica. Arch Dermatol. 1979;115(8):982-3. 2. Savk E, Savk SO, Bolukbasi O, et al. Notalgia paresthetica: a study on pathogenesis. Int J Dermatol. 2000:39(10):754-9. 3. Raison-Peyron N, Meunier L, Acevedo M, Meynadier J. No- talgia paresthetica: clinical, physiopathological and therapeutic aspects. A study of 12 cases. J Eur Acad Dermatol Venereol. 1999;12(3):215-21. 4. Savk O, Savk E. Investigation of spinal pathology in notalgia par- esthetica. J Am Acad Dermatol. 2005;52(6):1085-7. 5. Springall DR, Karanth SS, Kirkham N, Darley CR, Polak JM. Symptoms of notalgia paresthetica may be explained by in- creased dermal innervation. J Invest Dermatol. 1991;97(3): 555- 61. 6. Savk E, Dikicioglu E, Culhaci N, Karaman G, Sendur N. Immu- nohistochemical findings in notalgia paresthetica. Dermatology. 2002;204(2):88-93. 7. Massey EW, Pleet AB. Electromyographic evaluation of notalgia paresthetica. Neurology. 1981;31(5):642. 8. Williams EH, Rosson GD, Elsamanoudi I, Dellon AL. Surgical decompression for notalgia paresthetica: a case report. Microsur- gery. 2010;30(1):70-2. 9. Savk E, Savk O, Sendur F. Transcutaneous electric nerve stimula- tion offers partial relief in notalgia paresthetica patients with a relevant spinal pathology. J Dermatol. 2007;34(5):315-9. 10. Goulden V, Highet AS, Shamy HK. Notalgia paraesthetica—re- port of an association with macular amyloidosis. Clin Exp Der- matol. 1994;19(4):346-9. 11. Wallengren J, Klinker M. Successful treatment of notalgia pares- thetica with topical capsaicin: vehicle-controlled, double-blind, crossover study. J Am Acad Dermatol. 1995;32(2):287-9. 12. Weinfeld PK. Successful treatment of notalgia paresthetica with botulinum toxin type A. Arch Dermatol. 2007;143(8):980-2. 13. Goulden V, Toomey PJ, Highet AS. Successful treatment of notal- gia paresthetica with a paravertebral local anesthetic block. J Am Acad Dermatol. 1998;38(1):114-6. 14. Loosemore MP, Bordeaux JS, Bernhard JD. Gabapentin treat- ment for notalgia paresthetica, a common isolated peripheral sensory neuropathy [letter]. J Eur Acad Dermatol Venereol. 2007;21(10):1440-1. 15. Savk E, Bolukbasi O, Akyol A, Karaman G. Open pilot study on oxcarbazepine for the treatment of notalgia paresthetica. J Am Acad Dermatol. 2001;45(4):630-2. 16. Fleischer AB, Meade TJ, Fleischer AB. Notalgia parestheti- ca: successful treatment with exercises. Acta Derm Venereol. 2011;91(1):356-7. 17. Stellon A. Neurogenic pruritus: an unrecognized problem? A retrospective case series of treatment by acupuncture. Acupunct Med. 2002;20(4):186-190. 18. Richardson BS, Way BV, Speece AJ. Osteopathic manipulative treatment in the management of notalgia paresthetica. J Am Os- teopath Assoc. 2009;109(11):605-8.