Laboratory Studies

No laboratory studies are indicated for the diagnosis of Morton's neuroma.

Imaging Studies

Results of plain films are normal in Morton's neuroma.

Ultrasonography is gaining in popularity and may be equivalent in sensitivity to MRI in detecting Morton's neuroma.^{[6, 7, 8]} Indeed, a literature review by Bignotti et al indicated that ultrasonography and MRI are equally accurate for the diagnosis of Morton neuroma, with the modalities having sensitivities of 0.91 and 0.90, respectively.^[14]

Computed tomography (CT) scanning has been used but may not be as sensitive as MRI or ultrasonography. MRI, while not needed in most cases for establishing diagnosis of Morton's neuroma, has been studied widely.^{[4, 5]}Sensitivity of 87% and specificity as high as 100% have been reported. Asymptomatic neuromas may occur and confound accurate diagnosis.

Indications exist that Morton's neuromas smaller than 5 mm in diameter may not be significant clinically and that other diagnoses may be excluded carefully before such a small lesion is diagnosed as a symptomatic Morton's neuroma. Imaging with T1 weighting in a coronal plane is recommended for best visualization. In addition, on T2 imaging, the low signal of a Morton's neuroma may help to differentiate it from a true neuroma, ganglion cyst, or intermetatarsal bursal fluid collection.

Contrast enhancement usually is demonstrated with Morton's neuromas.

Other Tests

Electromyography and nerve conduction study (EMG/NCS) of Morton's neuroma are not used often because of the technical difficulty in performing them; needle stimulation of the common digital nerve and pickup on the adjacent toe or toes, which may be of short distance, is required. Surface stimulation results most often in volume conduction through the skin to the pickups because of the short distance involved and the large amount of stimulation needed to penetrate the deep tissue separating the nerve from the skin surface.

Procedures

Temporary elimination of pain and numbness in the associated webspace by a common digital nerve block with an anesthetic agent supports a diagnosis of Morton's neuroma. If numbness of the associated webspace occurs but no decrease in pain is noted, other diagnoses should be considered.

Histologic Findings

Tissue biopsy is neither needed nor recommended for Morton's neuroma.

Treatment & Management

Morton TG. Peculiar painful affection of fourth metatarsophalangeal articulation. Am J Med Sci. 1876. 71:37.
Munir U, Morgan S. Morton Neuroma. StatPearls. 2020 Jan. [QxMD MEDLINE Link]. [Full Text].
Valero J, Gallart J, Gonzalez D, Deus J, Lahoz M. Multiple interdigital neuromas: a retrospective study of 279 feet with 462 neuromas. J Foot Ankle Surg. 2015 May-Jun. 54 (3):320-2. [QxMD MEDLINE Link].
Zanetti M, Weishaupt D. MR imaging of the forefoot: Morton neuroma and differential diagnoses. Semin Musculoskelet Radiol. 2005 Sep. 9(3):175-86.
Claassen L, Bock K, Ettinger M, Waizy H, Stukenborg-Colsman C, Plaass C. Role of MRI in detection of Morton's neuroma. Foot Ankle Int. 2014 Oct. 35 (10):1002-5. [QxMD MEDLINE Link].
Pastides P, El-Sallakh S, Charalambides C. Morton's neuroma: A clinical versus radiological diagnosis. Foot Ankle Surg. 2012 Mar. 18(1):22-4. [QxMD MEDLINE Link].
Xu Z, Duan X, Yu X, Wang H, Dong X, Xiang Z. The accuracy of ultrasonography and magnetic resonance imaging for the diagnosis of Morton's neuroma: a systematic review. Clin Radiol. 2015 Apr. 70 (4):351-8. [QxMD MEDLINE Link].
Ata AM, Onat SS, Ozcakar L. Ultrasound-Guided Diagnosis and Treatment of Morton's Neuroma. Pain Physician. 2016 Feb. 19 (2):E355-8. [QxMD MEDLINE Link]. [Full Text].
Morgan P, Monaghan W, Richards S. A systematic review of ultrasound-guided and non-ultrasound-guided therapeutic injections to treat Morton's neuroma. J Am Podiatr Med Assoc. 2014 Jul. 104 (4):337-48. [QxMD MEDLINE Link].
Mahadevan D, Attwal M, Bhatt R, Bhatia M. Corticosteroid injection for Morton's neuroma with or without ultrasound guidance: a randomised controlled trial. Bone Joint J. 2016 Apr. 98-B (4):498-503. [QxMD MEDLINE Link].
Kim JY, Choi JH, Park J, et al. An anatomical study of Morton's interdigital neuroma: the relationship between the occurring site and the deep transverse metatarsal ligament (DTML). Foot Ankle Int. 2007 Sep. 28(9):1007-10. [QxMD MEDLINE Link].
Mahadevan D, Venkatesan M, Bhatt R, Bhatia M. Diagnostic Accuracy of Clinical Tests for Morton's Neuroma Compared With Ultrasonography. J Foot Ankle Surg. 2015 Jul-Aug. 54 (4):549-53. [QxMD MEDLINE Link].
O'Connor FG, Wilder RP, Nirschl R. Foot Injuries in the Runner. In:Textbook of Running Medicine. New York: McGraw-Hill; 2001. 258-260.
Bignotti B, Signori A, Sormani MP, Molfetta L, Martinoli C, Tagliafico A. Ultrasound versus magnetic resonance imaging for Morton neuroma: systematic review and meta-analysis. Eur Radiol. 2015 Aug. 25 (8):2254-62. [QxMD MEDLINE Link].
Akermark C, Saartok T, Zuber Z. A prospective 2-year follow-up study of plantar incisions in the treatment of primary intermetatarsal neuromas (Morton's neuroma). Foot Ankle Surg. 2008. 14(2):67-73. [QxMD MEDLINE Link].
Monacelli G, Cascioli I, Prezzemolo G, Spagnoli A, Irace S. [Surgical treatment of Morton's neuroma: our experience and literature review]. Clin Ter. 2008 May-Jun. 159(3):165-7. [QxMD MEDLINE Link].
Valente M, Crucil M, Alecci V. Operative treatment of interdigital Morton's neuroma. Chir Organi Mov. 2008 May. 92(1):39-43. [QxMD MEDLINE Link].
Lee KT, Lee YK, Young KW, et al. Results of operative treatment of double Morton's neuroma in the same foot. J Orthop Sci. 2009 Sep. 14(5):574-8. [QxMD MEDLINE Link].
Bucknall V, Rutherford D, MacDonald D, Shalaby H, McKinley J, Breusch SJ. Outcomes following excision of Morton's interdigital neuroma: a prospective study. Bone Joint J. 2016 Oct. 98-B (10):1376-81. [QxMD MEDLINE Link].
Valisena S, Petri GJ, Ferrero A. Treatment of Morton's neuroma: a systematic review. Foot Ankle Surg. 2017 Apr 5. [QxMD MEDLINE Link].
Villas C, Florez B, Alfonso M. Neurectomy versus neurolysis for Morton's neuroma. Foot Ankle Int. 2008 Jun. 29(6):578-80. [QxMD MEDLINE Link].
Title CI, Schon LC. Morton neuroma: primary and secondary neurectomy. J Am Acad Orthop Surg. 2008 Sep. 16(9):550-7. [QxMD MEDLINE Link].
Pace A, Scammell B, Dhar S. The outcome of Morton's neurectomy in the treatment of metatarsalgia. Int Orthop. 2010 Apr. 34(4):511-5. [QxMD MEDLINE Link].
Faraj AA, Hosur A. The outcome after using two different approaches for excision of Morton's neuroma. Chin Med J (Engl). 2010 Aug. 123(16):2195-8. [QxMD MEDLINE Link].
Kundert HP, Plaass C, Stukenborg-Colsman C, Waizy H. Excision of Morton's Neuroma Using a Longitudinal Plantar Approach: A Midterm Follow-up Study. Foot Ankle Spec. 2015 Aug 7. [QxMD MEDLINE Link].
Habashy A, Sumarriva G, Treuting RJ. Neurectomy Outcomes in Patients With Morton Neuroma: Comparison of Plantar vs Dorsal Approaches. Ochsner J. 2016 Winter. 16 (4):471-4. [QxMD MEDLINE Link]. [Full Text].
Killen MC, Karpe P, Limaye R. Plantar approach for Morton's neuroma: an effective technique for primary excision. Foot (Edinb). 2015 Dec. 25 (4):232-4. [QxMD MEDLINE Link].
Reichert P, Zimmer K, Witkowski J, Wnukiewicz W, Kulinski S, Gosk J. Long-Term Results of Neurectomy Through a Dorsal Approach in the Treatment of Morton's Neuroma. Adv Clin Exp Med. 2016 Mar-Apr. 25 (2):295-302. [QxMD MEDLINE Link].
Lee J, Kim J, Lee M, Chu I, Lee S, Gwak H. Morton's Neuroma (Interdigital Neuralgia) Treated with Metatarsal Sliding Osteotomy. Indian J Orthop. 2017 Nov-Dec. 51 (6):692-6. [QxMD MEDLINE Link]. [Full Text].
Rout R, Tedd H, Lloyd R, et al. Morton's neuroma: diagnostic accuracy, effect on treatment time and costs of direct referral to ultrasound by primary care physicians. Qual Prim Care. 2009. 17(4):277-82. [QxMD MEDLINE Link].
Yap LP, McNally E. Patient's assessment of discomfort during ultrasound-guided injection of Morton's neuroma: selecting the optimal approach. J Clin Ultrasound. 2012 May 15. [QxMD MEDLINE Link].
Markovic M, Crichton K, Read JW, et al. Effectiveness of ultrasound-guided corticosteroid injection in the treatment of Morton's neuroma. Foot Ankle Int. 2008 May. 29(5):483-7. [QxMD MEDLINE Link].
Edwards SR, Fleming S, Landorf KB. Efficacy of a Single Corticosteroid Injection for Morton's Neuroma in Adults: A Systematic Review. J Am Podiatr Med Assoc. 2021 Jul 1. 111 (4):[QxMD MEDLINE Link].
Hau MYT, Thomson L, Aujla R, Madhadevan D, Bhatia M. Medium-Term Results of Corticosteroid Injections for Morton's Neuroma. Foot Ankle Int. 2021 Apr. 42 (4):464-8. [QxMD MEDLINE Link].
Lizano-Diez X, Gines-Cespedosa A, Alentorn-Geli E, et al. Corticosteroid Injection for the Treatment of Morton's Neuroma: A Prospective, Double-Blinded, Randomized, Placebo-Controlled Trial. Foot Ankle Int. 2017 Sep. 38 (9):944-51. [QxMD MEDLINE Link].
Park YH, Kim TJ, Choi GW, Kim HJ. Prediction of Clinical Prognosis according to Intermetatarsal Distance and Neuroma Size on Ultrasonography in Morton Neuroma: A Prospective Observational Study. J Ultrasound Med. 2019 Apr. 38 (4):1009-14. [QxMD MEDLINE Link]. [Full Text].
Fridman R, Cain JD, Weil L Jr. Extracorporeal shockwave therapy for interdigital neuroma: a randomized, placebo-controlled, double-blind trial. J Am Podiatr Med Assoc. 2009 May-Jun. 99(3):191-3. [QxMD MEDLINE Link].
Moore JL, Rosen R, Cohen J, Rosen B. Radiofrequency thermoneurolysis for the treatment of Morton's neuroma. J Foot Ankle Surg. 2012 Jan-Feb. 51(1):20-2. [QxMD MEDLINE Link].
Mahadevan D, Salmasi M, Whybra N, Nanda A, Gaba S, Mangwani J. What factors predict the need for further intervention following corticosteroid injection of Morton's neuroma?. Foot Ankle Surg. 2016 Mar. 22 (1):9-11. [QxMD MEDLINE Link].
Munir U, Morgan S. Morton Neuroma. 2018 Jan. [QxMD MEDLINE Link]. [Full Text].

Media Gallery

Plantar view showing the relationships between the metatarsal heads, the intermetatarsal ligament, and the neuroma.
Neurectomy: typical incision location.
Neurectomy: superficial exposure.
Neurectomy: deeper dissection.
Neuroma and adherent fibrofatty tissue.

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Author

Kevin Berry, MD Physical Medicine and Rehabilitation Physician, Rehabilitation Options of Issaquah

Kevin Berry, MD is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation, International Spine Intervention Society

Disclosure: Nothing to disclose.

Coauthor(s)

Peter G Gonzalez, MD Orthopaedic Institute of Central Jersey

Peter G Gonzalez, MD is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation, American Association of Neuromuscular and Electrodiagnostic Medicine, American College of Sports Medicine, Physiatric Association of Spine, Sports and Occupational Rehabilitation

Disclosure: Nothing to disclose.

Richard G Bowman, II, MD Rehabilitation and Electrodiagnostic Director, Physical Medicine and Rehabilitation, Pain Management, The Center for Pain Relief

Richard G Bowman, II, MD is a member of the following medical societies: American Medical Association

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Michael T Andary, MD, MS Professor, Residency Program Director, Department of Physical Medicine and Rehabilitation, Michigan State University College of Osteopathic Medicine

Michael T Andary, MD, MS is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation, American Association of Neuromuscular and Electrodiagnostic Medicine, American Medical Association, Association of Academic Physiatrists

Disclosure: Nothing to disclose.

Chief Editor

Dean H Hommer, MD Chief Medical Officer, Corpus Christi Medical Center

Dean H Hommer, MD is a member of the following medical societies: American Academy of Pain Medicine, American Academy of Physical Medicine and Rehabilitation, American Association for Physician Leadership, American Association of Neuromuscular and Electrodiagnostic Medicine, American College of Healthcare Executives, Texas Medical Association

Disclosure: Nothing to disclose.