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Coexistence of rare varieties of palmaris profundus and flexor superficialis muscle
- Department of Anatomical Dissection and Donation, Medical University of Lodz, Poland
- Orthopaedics and Paediatric Orthopaedics Department, Medical University of Lodz, Poland
open access
Abstract
The superficial layer of the anterior compartment of the forearm is characterized by different morphological variations. During standard anatomical dissection, two morphological variations in the superficial compartment of the forearm were observed. The first one was the palmaris profundus, which originated from the radius and distally fused with the tendon to 3rd digit (from the flexor digitorum superficialis muscle) inserted on the medial phalanx of the third digit. The second variation was a distinct superficial flexor of the 4th digit represented by one muscle belly with originated from a common mass from the medial humeral epicondyle, passes through the carpal tunnel, and is inserted into the medial phalanx of the fourth digit. The flexor digitorum superficialis muscle was located deeply to it and it was divided only into three tendons (to 2nd, 3rd, and 5th digits). Tendons connected to the 2nd and 3rd digits were crossed with each other at the level of carpal tunnel. From the humeroulnar head of the flexor digitorum superficialis muscle, an additional muscle belly was arising and its tendon was fused with the superficial flexor of the fourth digit. Knowledge about morphological variations in this region is clinically important because of the direct correlation with the median nerve, and the possibility to cause carpal tunnel syndrome.
Abstract
The superficial layer of the anterior compartment of the forearm is characterized by different morphological variations. During standard anatomical dissection, two morphological variations in the superficial compartment of the forearm were observed. The first one was the palmaris profundus, which originated from the radius and distally fused with the tendon to 3rd digit (from the flexor digitorum superficialis muscle) inserted on the medial phalanx of the third digit. The second variation was a distinct superficial flexor of the 4th digit represented by one muscle belly with originated from a common mass from the medial humeral epicondyle, passes through the carpal tunnel, and is inserted into the medial phalanx of the fourth digit. The flexor digitorum superficialis muscle was located deeply to it and it was divided only into three tendons (to 2nd, 3rd, and 5th digits). Tendons connected to the 2nd and 3rd digits were crossed with each other at the level of carpal tunnel. From the humeroulnar head of the flexor digitorum superficialis muscle, an additional muscle belly was arising and its tendon was fused with the superficial flexor of the fourth digit. Knowledge about morphological variations in this region is clinically important because of the direct correlation with the median nerve, and the possibility to cause carpal tunnel syndrome.
Keywords
palmaris profundus, flexor digitorum superficialis, accessory structure, median nerve entrapment, carpal tunnel, accessory tendon to the fourth finger, neuropathy, ulnar artery
Title
Coexistence of rare varieties of palmaris profundus and flexor superficialis muscle
Journal
Issue
Article type
Case report
Published online
2023-06-19
Page views
275
Article views/downloads
179
DOI
Pubmed
Keywords
palmaris profundus
flexor digitorum superficialis
accessory structure
median nerve entrapment
carpal tunnel
accessory tendon to the fourth finger
neuropathy
ulnar artery
Authors
Nicol Zielinska
Andrzej Borowski
Marek Drobniewski
Łukasz Olewnik
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