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Anatomical variation of quadratus plantae in relation to flexor hallucis longus and flexor digitorum longus: a rare case
- Department of Anatomical Sciences, Kerman University of Medical Sciences, Kerman, Iran
- Department of Anatomical Sciences, Kerman University of Medical Sciences, Kerman, Iran
open access
Abstract
The quadratus plantae (QP) is considered as a part of the plantar intrinsic foot muscles. This muscle has two lateral and medial heads of origin, both of which arise from the plantar surface of calcaneus, and insert into the tendon of flexor digitorum longus (FDL). Various functions have been attributed to the QP muscle, which includes assisting the plantar flexion of the lateral four toes, straightening the oblique pull of FDL and etc. Several anatomical variations of the QP muscle have been reported in the literature. During a routine dissection in the Department of Anatomy at Kerman University of Medical Sciences, a variant plantar muscle was observed in a 40-year-old male cadaver. In the present case, we report a rare variation associated with the insertion pattern of this muscle, which is reported for the first time in Iran. The tendinous end of the QP muscle was divided into three tendons and were then inserted to the inferior surface of 2nd, 3rd and 4th tendons of FDL. Also, a slim tendinous interconnection was also observed between the QP and flexor hallucis longus (FHL). The lack of connection between the FDL and FHL tendons was the other rare variation of this case. Exact knowledge of the possible variations of the QP muscle is of utmost importance to foot surgeons, clinicians and also anatomists.
Abstract
The quadratus plantae (QP) is considered as a part of the plantar intrinsic foot muscles. This muscle has two lateral and medial heads of origin, both of which arise from the plantar surface of calcaneus, and insert into the tendon of flexor digitorum longus (FDL). Various functions have been attributed to the QP muscle, which includes assisting the plantar flexion of the lateral four toes, straightening the oblique pull of FDL and etc. Several anatomical variations of the QP muscle have been reported in the literature. During a routine dissection in the Department of Anatomy at Kerman University of Medical Sciences, a variant plantar muscle was observed in a 40-year-old male cadaver. In the present case, we report a rare variation associated with the insertion pattern of this muscle, which is reported for the first time in Iran. The tendinous end of the QP muscle was divided into three tendons and were then inserted to the inferior surface of 2nd, 3rd and 4th tendons of FDL. Also, a slim tendinous interconnection was also observed between the QP and flexor hallucis longus (FHL). The lack of connection between the FDL and FHL tendons was the other rare variation of this case. Exact knowledge of the possible variations of the QP muscle is of utmost importance to foot surgeons, clinicians and also anatomists.
Keywords
quadratus plantae, flexor digitorum longus, flexor hallucis longus, foot, tendon
Title
Anatomical variation of quadratus plantae in relation to flexor hallucis longus and flexor digitorum longus: a rare case
Journal
Issue
Article type
Case report
Pages
412-415
Published online
2022-03-29
Page views
2278
Article views/downloads
926
DOI
Pubmed
Bibliographic record
Folia Morphol 2023;82(2):412-415.
Keywords
quadratus plantae
flexor digitorum longus
flexor hallucis longus
foot
tendon
Authors
S. Haratizadeh
S. Seyyedin
S. N. Nematollahi-mahani
- Athavale SA, Geetha GN, Swathi N. Morphology of flexor digitorum accessorius muscle. Surg Radiol Anat. 2012; 34(4): 367–372.
- Chadwick C, Whitehouse SL, Saxby TS. Long-term follow-up of flexor digitorum longus transfer and calcaneal osteotomy for stage II posterior tibial tendon dysfunction. Bone Joint J. 2015; 97-B(3): 346–352.
- Cunningham DJ, Koshi R. Cunningham's manual of practical anatomy. 16th ed. Oxford, New York 2017.
- Gray H, Standring S. Gray's Anatomy: the anatomical basis of clinical practice. 41st ed. Elsevier, Philadelphia 2016.
- Hunt KJ, Cohen BE, Davis WH, et al. Surgical treatment of insertional achilles tendinopathy with or without flexor hallucis longus tendon transfer: a prospective, randomized study. Foot Ankle Int. 2015; 36(9): 998–1005.
- Hur MS, Kim JH, Woo JS, et al. An anatomic study of the quadratus plantae in relation to tendinous slips of the flexor hallucis longus for gait analysis. Clin Anat. 2011; 24(6): 768–773.
- Kelly LA, Kuitunen S, Racinais S, et al. Recruitment of the plantar intrinsic foot muscles with increasing postural demand. Clin Biomech (Bristol, Avon). 2012; 27(1): 46–51.
- Last RJ. Anatomy: regional and applied. 7th ed. Churchill Livingstone, Edinburgh 1985.
- Le Double AF. Traité des variations du système musculaire de l'homme: et de leur signification au point de vue de l'anthropologie zoologique. Reinwald, Paris 1897.
- Nasir N. A rare instance of a tendinous interconnection between flexor hallucis longus and flexor digitorum accessorius. Int J Anat Var2013. 2013; 6(1): 18–19.
- Neumann D. Kinesiology of the musculoskeletal system: foundations for rehabilitation. 3rd ed. Elsevier, St. Louis, Missouri 2017.
- O'Sullivan E, Carare-Nnadi R, Greenslade J, et al. Clinical significance of variations in the interconnections between flexor digitorum longus and flexor hallucis longus in the region of the knot of Henry. Clin Anat. 2005; 18(2): 121–125.
- Pretterklieber B. Morphological characteristics and variations of the human quadratus plantae muscle. Ann Anat. 2018; 216: 9–22.
- Pretterklieber B. The high variability of the chiasma plantare and the long flexor tendons: Anatomical aspects of tendon transfer in foot surgery. Ann Anat. 2017; 211: 21–32.
- Schroeder KL, Rosser BW, Kim SY. Fiber type composition of the human quadratus plantae muscle: a comparison of the lateral and medial heads. J Foot Ankle Res. 2014; 7(1): 54.
- Sooriakumaran P, Sivananthan S. Why does man have a quadratus plantae? A review of its comparative anatomy. Croat Med J. 2005; 46(1): 30–35.
- Talhar SS, Sontakke BR, Wankhede V, et al. A rare variation of flexor digitorum accessorius insole and its phylogenetic significance. J Mahatma Gandhi Inst Med Sci. 2017; 22(1): 44.
- Testut L. Les anomalies musculaires chez l'homme. G Masson, Paris 1884.