Knuckle Pads Clinical Presentation

  • Author: Cheryl J Barnes, MD; Chief Editor: Dirk M Elston, MD   more...
 
Updated: Jan 17, 2012
 

History

Most patients are asymptomatic. Firm skin-colored papules appear sequentially in multiple sites overlying the MCP and PIP joints of the hands. Individual lesions enlarge into well-defined plaques and nodules. Though complaints of pain or functional impairment of fine motor skills are rare, cosmetic concerns frequently are raised. A history of repetitive trauma often is elicited.

Next

Physical

Knuckle pads are well-circumscribed firm dermal papules, nodules, or plaques approximately 0.5-3 cm in size, located on the extensor aspect of the PIP or MCP joints. If subjected to repetitive injury, knuckle pads may develop over virtually any bony prominence, but the PIP joint area is affected most commonly.

Knuckle pad over the proximal interphalangeal joinKnuckle pad over the proximal interphalangeal joint. Multiple knuckle pads on various joints of the hanMultiple knuckle pads on various joints of the hand.
Previous
Next

Causes

Most knuckle pads are idiopathic or are related to repetitive trauma. Work-related trauma with repeated motions or rubbing of the PIP joints or knuckles, as seen in live-chicken hangers in a poultry processing plant,[4] has been reported. Athletes, such as boxers, have been known to traumatize their knuckles and fingers in a repetitive fashion, causing knuckle pads.[5, 6] Surfers have developed "surfer's knots" from repeated friction between the surfboard and the body part exposed to the repeated trauma.[7] A few cases involving the toes have been reported; these cases were thought to be sequelae of ill-fitting shoes.

Psychologically disturbed children who bite and suck their fingers cause thickenings that resemble knuckle pads to occur in the skin in the traumatized areas. Patients with bulimia who use their knuckles or fingers to induce emesis sometimes develop fibrotic papules resembling knuckle pads.[8]

Some cases of knuckle pads are familial. They have been associated with the autosomal dominant palmoplantar keratoderma with and without ichthyosis vulgaris. Knuckle pads were found in 2 families with autosomal dominant sensorineural deafness and leukonychia (Bart-Pumphrey syndrome).[9] Knuckle pads also have been reported in pseudoxanthoma elasticum.[10, 11, 12] Dupuytren disease, Peyronie disease, and Ledderhose disease are at times observed together, and the triad may be associated with knuckle pads.[13, 14, 15] Knuckle pads also have been associated with esophageal cancer,[16] hyperkeratosis,[17] oral leukoplakia,[16] and clubbed fingers.[18] One case report links phenytoin with polyfibromatous syndrome.[19]

Previous
Proceed to Differential Diagnoses
 
 
Contributor Information and Disclosures
Author

Cheryl J Barnes, MD  Dermatologist, McIntosh Clinic, PC

Cheryl J Barnes, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

Coauthor(s)

Loretta Davis, MD  Professor, Department of Internal Medicine, Division of Dermatology, Medical College of Georgia

Loretta Davis, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

Specialty Editor Board

Gregory J Raugi, MD, PhD  Professor, Department of Internal Medicine, Division of Dermatology, University of Washington at Seattle School of Medicine; Chief, Dermatology Section, Primary and Specialty Care Service, Veterans Administration Medical Center of Seattle

Gregory J Raugi, MD, PhD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

Michael J Wells, MD  Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center, Paul L Foster School of Medicine

Michael J Wells, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Medical Association, and Texas Medical Association

Disclosure: Nothing to disclose.

Edward F Chan, MD  Clinical Assistant Professor, Department of Dermatology, University of Pennsylvania School of Medicine

Edward F Chan, MD is a member of the following medical societies: American Academy of Dermatology, American Society of Dermatopathology, and Society for Investigative Dermatology

Disclosure: Nothing to disclose.

Catherine M Quirk, MD  Clinical Assistant Professor, Department of Dermatology, University of Pennsylvania

Catherine M Quirk, MD is a member of the following medical societies: Alpha Omega Alpha and American Academy of Dermatology

Disclosure: Nothing to disclose.

Chief Editor

Dirk M Elston, MD  Director, Ackerman Academy of Dermatopathology, New York

Dirk M Elston, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

References

  1. Garrod AE. On an unusual form of nodule upon joints of the fingers. St. Bartholomew's Hosp Rep. 1893;29:157-161.

  2. Allison JR Jr, Allison JR Sr. Knuckle pads. Arch Dermatol. Mar 1966;93(3):311-6. [Medline].

  3. Paller AS, Hebert AA. Knuckle pads in children. Am J Dis Child. Sep 1986;140(9):915-7. [Medline].

  4. Richards TB, Gamble JF, Castellan RM, Mathias CG. Knuckle pads in live-chicken hangers. Contact Dermatitis. Jul 1987;17(1):13-6. [Medline].

  5. Cohen PR, Eliezri YD, Silvers DN. Athlete's nodules. J Am Acad Dermatol. Feb 1991;24(2 Pt 1):317-8. [Medline].

  6. Kanerva L. Knuckle pads from boxing. Eur J Dermatol. Jul-Aug 1998;8(5):359-61. [Medline].

  7. Swift S. Surfers' "Knots". JAMA. Apr 19 1965;192:223-4. [Medline].

  8. Wynn DR, Martin MJ. A physical sign of bulimia. Mayo Clin Proc. Oct 1984;59(10):722. [Medline].

  9. Bart RS, Pumphrey RE. Knuckle pads, leukonychia and deafness. A dominantly inherited syndrome. N Engl J Med. Jan 26 1967;276(4):202-7. [Medline].

  10. Stankler L. Pseudoxanthoma elasticum with a knuckle pad on the thumb. Acta Derm Venereol. 1967;47(4):263-6. [Medline].

  11. Codispoti A, Colombo E, Zocchi L, et al. Knuckle pads, in an epidermal palmoplantar keratoderma patient with Keratin 9 R163W transgrediens expression. Eur J Dermatol. Mar-Apr 2009;19(2):114-8. [Medline].

  12. Du ZF, Wei W, Wang YF, Chen XL, Chen CY, Liu WT, et al. A novel mutation within the 2B rod domain of keratin 9 in a Chinese pedigree with epidermolytic palmoplantar keratoderma combined with knuckle pads and camptodactyly. Eur J Dermatol. Sep-Oct 2011;21(5):675-9. [Medline].

  13. Lagier R, Meinecke R. Pathology of "knuckle pads". Study of four cases. Virchows Arch A Pathol Anat Histol. 1975;365(3):185-91. [Medline].

  14. Mikkelsen OA. Knuckle pads in Dupuytren's disease. Hand. Oct 1977;9(3):301-5. [Medline].

  15. Wooldridge WE. Four related fibrosing diseases. When you find one, look for another. Postgrad Med. Aug 1988;84(2):269-71, 274. [Medline].

  16. Ritter SB, Petersen G. Esophageal cancer, hyperkeratosis, and oral leukoplakia. Occurrence in a 25-year-old woman. JAMA. Apr 19 1976;235(16):1723. [Medline].

  17. Leonard NJ, Krol AL, Bleoo S, Somerville MJ. Sensorineural hearing loss, striate palmoplantar hyperkeratosis, and knuckle pads in a patient with a novel connexin 26 (GJB2) mutation. J Med Genet. Jan 2005;42(1):e2. [Medline].

  18. Koba S, Misago N, Narisawa Y. Knuckle pads associated with clubbed fingers. J Dermatol. Dec 2007;34(12):838-40. [Medline].

  19. Pierard GE, Lapiere CM. Phenytoin dependent fibrosis in polyfibromatosis syndrome. Br J Dermatol. Mar 1979;100(3):335-41. [Medline].

  20. Glicenstein J, Costa R. [Pachydermodactyly: a report of two cases]. Chir Main. Aug 2004;23(4):205-7. [Medline].

  21. Verbov J. Letter: Pachydermodactyly: a variant of the true knuckle pad. Arch Dermatol. Apr 1975;111(4):524. [Medline].

  22. Bettoni L, Bani L, Airò P. Rheumatoid nodules: the importance of a correct differential diagnosis. Eur Ann Allergy Clin Immunol. Jun 2011;43(3):95-6. [Medline].

  23. Weiss E, Amini S. A novel treatment for knuckle pads with intralesional Fluorouracil. Arch Dermatol. Nov 2007;143(11):1458-60. [Medline].

  24. Quinn KJ. Silicone gel in scar treatment. Burns Incl Therm Inj. Oct 1987;13 Suppl:S33-40. [Medline].

  25. Addison A. Knuckle pads causing extensor tendon tethering. J Bone Joint Surg Br. Jan 1984;66(1):128-30. [Medline].

 
Previous
Next
 
Knuckle pad over the proximal interphalangeal joint.
Multiple knuckle pads on various joints of the hand.
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2012 by WebMD LLC.
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.