Online first
Case report
Published online: 2023-07-26

open access

Page views 239
Article views/downloads 193
Get Citation

Connect on Social Media

Connect on Social Media

Co-occurrence of asymmetrical bilateral extensor carpi radialis intermedius and bilateral sternalis muscles in an anatomical donor

Oheneba Boadum1, Yue F. Lu2


The presence of anatomical variants in the body may pose clinical challenges to inexperienced surgeons or clinicians and could cause misdiagnosis or treatment errors. Similarly, anatomical variations in cadavers pose educational dilemmas to students in gross anatomy dissection because of the inadequate coverage of anatomical variants in currently available resources, including textbooks. Students experience challenges in their learning experience, dissection process, and translation of clinically relevant information when presented with an anatomical variation. The authors report the rare finding of a bilateral sternalis muscle variant and asymmetrically bilateral extensor carpi radialis intermedius muscles in a single anatomical donor during dissection and the dilemma of students to find out what they were.

Article available in PDF format

View PDF Download PDF file


  1. Albright JA, Linburg RM. Common variations of the radial writs extensors. J Hand Surg Am. 1978; 3(2): 134–138.
  2. Bailey PM, Tzarnas CD. The sternalis muscle: a normal finding encountered during breast surgery. Plast Reconstr Surg. 1999; 103(4): 1189–1190.
  3. Ge Z, Tong Y, Zhu S, et al. Prevalence and variance of the sternalis muscle: a study in the Chinese population using multi-detector CT. Surg Radiol Anat. 2014; 36(3): 219–224.
  4. Jelev L, Georgiev G, Surchev L. The sternalis muscle in the Bulgarian population: classification of sternales. J Anat. 2002; 199(3): 359–363.
  5. Loukas M, Bowers M, Hullett J. Sternalis muscle: a mystery still. Folia Morphol. 2004; 63(2): 147–149.
  6. Nayak SR, Madhan Kumar SJ, Krishnamurthy A, et al. An additional radial wrist extensor and its clinical significance. Ann Anat. 2007; 189(3): 283–286.
  7. Raikos A, Paraskevas G, Yusuf F, et al. Sternalis muscle. Ann Plast Surg. 2011; 67(6): 646–648.
  8. Salazar D, Hazel A, Marra G. Isolated avulsion of extensor carpi radialis longus and brachioradialis origins: a case report and surgical repair technique. Am J Orthop (Belle Mead NJ). 2015; 44(10): E394–397.
  9. Salval A, Scevola A, Baruffaldi Preis FW. Sternalis muscle: an uncommon finding during aesthetic breast surgery. Aesthet Surg J. 2012; 32(7): 903–905.
  10. Smith J, Pourcho AM, Kakar S. Sonographic appearance of the extensor carpi radialis intermedius tendon. PM R. 2015; 7(7): 789–791.
  11. Snosek M, Tubbs RS, Loukas M. Sternalis muscle, what every anatomist and clinician should know. Clin Anat. 2014; 27(6): 866–884.
  12. Sonne JWH. Prevalence of the sternalis muscle in a sample of routinely dissected human cadavers. Surg Radiol Anat. 2020; 42(1): 87–90.
  13. Vessal S, Rai SB. Accessory extensor carpi radialis brevis muscle, a pseudomass of the distal forearm: ultrasound and MR appearances — case report and literature review. Clin Radiol. 2006; 61(5): 442–445.
  14. Wood JN. IX. Variations in human myology observed during the Winter session of 1865-66 at King’s College, London. Proc R Soc Lond. 1866; 15: 229–244.
  15. Wood VE. The extensor carpi radialis intermedius tendon. J Hand Surg Am. 1988; 13(2): 242–245.
  16. Young RC, Sañudo JR, Mirapeix RM, et al. Accessory tendons of the extensor carpi radialis muscles. Eur J Anat. 1998; 2(1): 1–84.
  17. Zancolli E. Surgery for the quadriplegic hand with active, strong wrist extension preserved. A study of 97 cases. Clin Orthop Relat Res. 1975; 112(1): 101–113.