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Degenerated lumbricals in the feet of adult human cadavers: case series

  • Hare Krishna (Department of Anatomy, All India Institute of Medical Sciences) ;
  • Rati Tandon (Department of Anatomy, Mahatma Gandhi University of Medical College and Hospital) ;
  • Tony George Jacob (Department of Anatomy, All India Institute of Medical Sciences)
  • Received : 2022.11.10
  • Accepted : 2023.01.25
  • Published : 2023.06.30

Abstract

In the foot, the lumbricals flex the metatarsophalangeal joints and extend the interphalangeal joints. The lumbricals are known to be affected in neuropathies. It is not known whether they may degenerate in normal individuals. Here, we report our findings of isolated degenerated lumbricals in seemingly normal feet of two cadavers. We explored lumbricals in 20 male and 8 female cadavers that were 60-80 years of age at the time of death. As part of routine dissection, we exposed the tendons of the flexor digitorum longus and the lumbricals. From the degenerated lumbricals, we took some tissue for paraffin-embedding, sectioning, and staining by hematoxylin and eosin, and Masson's trichrome technique. Of the 224 lumbricals studied, we found four apparently degenerated lumbricals in two male cadavers. In the first, the 2nd and 4th lumbricals in the left foot and the 2nd in the right foot were degenerated. In the second, the right 4th lumbrical was degenerated. Microscopically, the degenerated tissue was made of bundles of collagen. The lumbricals may have degenerated due to compression of their nerve supply. We cannot comment on whether the functionality of the feet were affected by these isolated degeneration of the lumbricals.

Keywords

Acknowledgement

We thank the relatives of all the persons who donated their precious bodies for educational and research purposes.

References

  1. Standring S. Gray's anatomy: the anatomical basis of clinical practice. 42nd ed. Elsevier; 2021. p. 979, 1458, 1462.
  2. Malhotra A, Kulesza R. A case report of an accessory flexor digitorum profundus indicis contributing the first lumbrical. Anat Cell Biol 2022;55:390-3.
  3. Koshi R. Cunningham's manual of practical anatomy. Volume 1, Upper and lower limbs. 16th ed. Oxford University Press; 2017. p. 248-52.
  4. Hur MS, Kim JH, Gil YC, Kim HJ, Lee KS. New insights into the origin of the lumbrical muscles of the foot: tendinous slip of the flexor hallucis longus muscle. Surg Radiol Anat 2015;37:1161-7.
  5. Sinnatamby CS. Last's anatomy: regional and applied. 12th ed. Churchill Livingstone; 2011. p. 163.
  6. Shawn Allen DC, Dabco IFW, Robert Lardner PT. The importance of the lumbricals [Internet]. Dynamic Chiropractic; 2008 Apr 8 [cited 2022 Aug 22]. Available from: https://www.dynamicchiropractic.com/mpacms/dc/article.php?id=53168.
  7. Fiolkowski P, Brunt D, Bishop M, Woo R, Horodyski M. Intrinsic pedal musculature support of the medial longitudinal arch: an electromyography study. J Foot Ankle Surg 2003;42:327-33.
  8. Okamura K, Kanai S, Oki S, Tanaka S, Hirata N, Sakamura Y, Idemoto N, Wada H, Otsuka A. Does the weakening of intrinsic foot muscles cause the decrease of medial longitudinal arch height? J Phys Ther Sci 2017;29:1001-5.
  9. Kalin PJ, Hirsch BE. The origins and function of the interosseous muscles of the foot. J Anat 1987;152:83-91.
  10. Chaney DM, Lee MS, Khan MA, Krueger WA, Mandracchia VJ, Yoho RM. Study of ten anatomical variants of the foot and ankle. J Am Podiatr Med Assoc 1996;86:532-7.
  11. Drury RAB, Wallington EA. Carleton's histological technique. 5th ed. Oxford University Press; 1980. p. 57-149, 183-5.
  12. Jackman RW, Kandarian SC. The molecular basis of skeletal muscle atrophy. Am J Physiol Cell Physiol 2004;287:C834-43.
  13. Peri G. The "critical zones" of entrapment of the nerves of the lower limb. Surg Radiol Anat 1991;13:139-43.
  14. Schon LC, Baxter DE. Neuropathies of the foot and ankle in athletes. Clin Sports Med 1990;9:489-509.
  15. Bejjani FJ, Jahss MH. Le Double's study of muscle variations of the human body. Part II: muscle variations of the foot. Foot Ankle 1986;6:157-76.