eMedicine Specialties > Orthopedic Surgery > Foot & Ankle

Morton Neuroma: Workup

Author: Thomas M Schaller, MD, Clinical Assistant Professor, Department of Orthopedic Surgery, Kalamazoo Center for Medical Studies, Michigan State University; Medical Director of Orthopedic Trauma, Bronson Methodist Hospital
Contributor Information and Disclosures

Updated: May 9, 2008

Workup

Imaging Studies

  • A large body of literature addresses the use of imaging modalities to aid in the diagnosis of Morton neuroma. The condition is most commonly diagnosed based strictly upon the history and physical examination findings. In equivocal cases, the use of ultrasound, magnetic resonance imaging (MRI), or both may be helpful.6,7,8
    • The skill of the technologists and physicians performing and interpreting these studies plays a key role in determining just how valuable these modalities can be in clinical practice.
    • The ultrasound appearance is typically that of a hypoechoic oblong mass that is oriented along the long axis of the foot. Prospective studies in symptomatic patients reveal that ultrasound can be used reliably to detect the neuromas.9 Furthermore, they can be helpful in identifying contributing pathologic lesions, such as lipomas or bursae.10
    • MRI technology and applications continue to evolve and can provide reliable information regarding the pathoanatomy of the forefoot. The characteristic MRI findings of a Morton neuroma are low intensity on T1- and T2-weighted sequences due to the high degree of fibrous content. In contrast, an intermetatarsal bursa is associated with increased intensity on the T2-weighted images due to its fluid content.11 MRI with gadolinium contrast enhancement and with fat suppression probably provides the most reliable images for diagnosis.12

Diagnostic Procedures

  • An injection of local anesthetic with sterile technique may be useful in the diagnostic evaluation of Morton neuroma. The temporary resolution of pain, paresthesias, or both in response to the injection may confirm the location of the pathology. A positive response to the injection tends to be predictive of satisfactory postsurgical outcomes.

Histologic Findings

See Pathophysiology.

More on Morton Neuroma

Overview: Morton Neuroma
Workup: Morton Neuroma
Treatment: Morton Neuroma
Follow-up: Morton Neuroma
Multimedia: Morton Neuroma
References
[ CLOSE WINDOW ]

References

  1. Weinfeld SB, Myerson MS. Interdigital Neuritis: Diagnosis and Treatment. J Am Acad Orthop Surg. Nov 1996;4(6):328-335. [Medline].

  2. Coughlin MJ, Mann RA. Surgery of the Foot and Ankle. 7th ed. Mosby-Year Book;1999.

  3. Thompson FM, Deland JT. Occurrence of two interdigital neuromas in one foot. Foot Ankle. Jan 1993;14(1):15-7. [Medline].

  4. Levitsky KA, Alman BA, Jevsevar DS. Digital nerves of the foot: anatomic variations and implications regarding the pathogenesis of interdigital neuroma. Foot Ankle. May 1993;14(4):208-14. [Medline].

  5. Mulder J. The Causative Mechanism in Morton's Metatarsalgia. J Bone Joint Surg Br. 1951;33:94-95.

  6. Lee MJ, Kim S, Huh YM, Song HT, Lee SA, Lee JW, et al. Morton neuroma: evaluated with ultrasonography and MR imaging. Korean J Radiol. Mar-Apr 2007;8(2):148-55. [Medline].

  7. Zanetti M, Weishaupt D. MR imaging of the forefoot: Morton neuroma and differential diagnoses. Semin Musculoskelet Radiol. Sep 2005;9(3):175-86. [Medline].

  8. Giannini S, Bacchini P, Ceccarelli F, Vannini F. Interdigital neuroma: clinical examination and histopathologic results in 63 cases treated with excision. Foot Ankle Int. Feb 2004;25(2):79-84. [Medline].

  9. Read JW, Noakes JB, Kerr D. Morton''s metatarsalgia: sonographic findings and correlated histopathology. Foot Ankle Int. Mar 1999;20(3):153-61. [Medline].

  10. Iagnocco A, Coari G, Palombi G. Sonography in the study of metatarsalgia. J Rheumatol. Jun 2001;28(6):1338-40. [Medline].

  11. Timins ME. MR imaging of the foot and ankle. Foot Ankle Clin. Mar 2000;5(1):83-101, vi. [Medline].

  12. Terk MR, Kwong PK, Suthar M. Morton neuroma: evaluation with MR imaging performed with contrast enhancement and fat suppression. Radiology. Oct 1993;189(1):239-41. [Medline].

  13. Saygi B, Yildirim Y, Saygi EK, Kara H, Esemenli T. Morton neuroma: comparative results of two conservative methods. Foot Ankle Int. Jul 2005;26(7):556-9. [Medline].

  14. Valente M, Crucil M, Alecci V. Operative treatment of interdigital Morton's neuroma. Chir Organi Mov. Mar 14 2008;[Medline].

  15. Coughlin MJ, Pinsonneault T. Operative treatment of interdigital neuroma. A long-term follow-up study. J Bone Joint Surg Am. Sep 2001;83-A(9):1321-8. [Medline].

  16. Benedetti RS, Baxter DE, Davis PF. Clinical results of simultaneous adjacent interdigital neurectomy in the foot. Foot Ankle Int. May 1996;17(5):264-8. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

interdigital neuroma, interdigital neuritis, forefoot pain, forefoot paresthesias, forefoot numbness, foot pain, Inge retractor, neurectomy, plantar keratosis

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

Thomas M Schaller, MD, Clinical Assistant Professor, Department of Orthopedic Surgery, Kalamazoo Center for Medical Studies, Michigan State University; Medical Director of Orthopedic Trauma, Bronson Methodist Hospital
Thomas M Schaller, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Orthopaedic Surgeons, American Medical Association, AO Foundation, and Orthopaedic Trauma Association
Disclosure: Nothing to disclose.

Medical Editor

Heidi M Stephens, MD, MBA, Associate Professor, Department of Surgery, Division of Orthopedic Surgery, University of South Florida College of Medicine; Courtesy Joint Associate Professor, Department of Environmental and Occupational Health, University of South Florida College of Public Health
Heidi M Stephens, MD, MBA is a member of the following medical societies: Alpha Omega Alpha, American Academy of Orthopaedic Surgeons, American Medical Association, American Orthopaedic Foot and Ankle Society, and Florida Medical Association
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Shepard R Hurwitz, MD, Executive Director, American Board of Orthopaedic Surgery
Shepard R Hurwitz, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American Association for the Advancement of Science, American College of Rheumatology, American College of Sports Medicine, American College of Surgeons, American Diabetes Association, American Orthopaedic Association, American Orthopaedic Foot and Ankle Society, Association for the Advancement of Automotive Medicine, Eastern Orthopaedic Association, Orthopaedic Research Society, Orthopaedic Trauma Association, and Southern Orthopaedic Association
Disclosure: Nothing to disclose.

CME Editor

Dinesh Patel, MD, FACS, Associate Clinical Professor of Orthopedic Surgery, Harvard Medical School; Chief of Arthroscopic Surgery, Department of Orthopedic Surgery, Massachusetts General Hospital
Dinesh Patel, MD, FACS is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American Association of Physicians of Indian Origin, American College of International Physicians, and American College of Surgeons
Disclosure: Nothing to disclose.

Chief Editor

Jason H Calhoun, MD, FACS, Frank J Kloenne Chair in Orthopedic Surgery, Professor and Chair, Department of Orthopedics, The Ohio State University Medical Center
Jason H Calhoun, MD, FACS is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American College of Surgeons, American Diabetes Association, American Medical Association, American Orthopaedic Association, American Orthopaedic Foot and Ankle Society, Missouri State Medical Association, Musculoskeletal Infection Society, Southern Medical Association, Southern Orthopaedic Association, Texas Medical Association, and Texas Orthopaedic Association
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.