Type of Article : Case Report
Year: 2015 | Volume 3 | Issue 2 | Page No. 1024-1027
Date of Publication: 31-05-2015
VARIATIONS IN THE MUSCLES OF THE EXTENSOR COMPARTMENT OF THE FOREARM AND HAND AND ITS CLINICAL SIGNIFICANCE
Swati Tiwari 1, Anita Mahajan *2, Rohini Pakhiddey 3.
1 Senior Resident, Department Of Anatomy, Maulana Azad Medical College, New Delhi, India.
*2 Professor, Department Of Anatomy, Maulana Azad Medical College, New Delhi, India.
3 Assistant Professor, Department of Anatomy, Santosh Medical College, Ghaziabad, India.
Address: Prof. Dr. Anita Mahajan, Professor, Department Of Anatomy, Maulana Azad Medical College, New Delhi, India.
Background: The extensor musculature of the forearm and hand shows diverse variations. These can lead to various clinical conditions.
Case Report: During routine cadaveric dissection, variations were observed in the muscles of extensor compartment of the forearm. Their anatomical relations were documented and the embryological basis and clinical importance was stressed upon. During routine cadaveric dissection in a formalin fixed 58 year old male cadaver, variationsin the posterior compartment of the left forearm were noted, measured and appropriately photographed.
Observations:In the posterior compartment of the left forearm an accessory muscle was found originating from the posterior surface of ulna, just distal to the origin of extensor indicis. It traversed along with the tendons of extensor digitorum and extensor indicis in a common compartment underneath the extensor retinaculum and inserted onto the dorsal surface of the base of the proximal phalanx lateral to the tendon of extensor digitorum for the middle finger. Also, the extensor digitorum muscle divided only into three tendons instead of four- one each for the index, middle and ring finger. The three tendons inserted normally via the dorsal digital expansion but, the tendon for the ring finger gave an additional slip on the ulnar aspect, which inserted separately onto the base of the proximal phalanx of the ring finger.
Conclusion: Muscles in the extensor compartment of forearm may show diverse variations which have clinical relevance. Accessory muscles may be confused with soft tissue conditions like a ganglion. Supernumary tendons can be utilised for tendon transfers and muscle grafts. These variations must be brought to the knowledge of the surgeons performing hand surgeries.
KEY WORDS: Extensor muscles, forearm, accessory muscle, extensor digitorum, hand surgeries.
- Tan ST, Smith PJ. Anomalous extensor muscles of the hand: A review. The Journal of Hand Surgery. 1999 May;24(3):449-455.
- Johnson D. Forearm. In Gray’s Anatomy: The Anatomical Basis Of Clinical Practice. 40th edition. Edited by Standring S. Spain: Elsevier Churchill Livingstone; 2008: 839-856.
- von Schroeder HP, Botte MJ. The extensor medii proprius and anomalous extensor tendons to the long finger. J Hand Surg Am.1991 Nov;16(6):1141-5.
- Das P, Prabhu LV, Pai MM, Nayak V, Kumar G, Janardhanan JP. A Comprehensive Study of the Extensor Tendons to the Medial Four Digits of the Hand. Chang Gung Med J. 2011 Nov-Dec;34(6):612-619.
- Bharambe VK, Patel DK, Shevade SP, Manvikar PR. Presence of rare variation of double extensor medii proprius muscle on the dorsum of the hand. OA Case Reports. 2013 Jun 21;2(5):43.
- Celik S, Bilge O, Pinar Y, Govsa F. The anatomical variations of the extensor tendons to the dorsum of the hand. Clin Anat. 2008 Oct;21(7):652-9.
- Zilber S, Oberlin C. Anatomical variations of the extensor tendons to the fingers over the dorsum of the hand: a study of 50 hands and a review of the literature. Plast Reconstr Surg. 2004 Jan;113(1):214-21.
- Seradge H, Tian W, Baer C, Anatomic variation of the extensor tendons to the ring and little fingers: a cadaver dissection study. Am J Orthop. 1999, 28(7):399–401.
- Jing Li, Mao QH. Accessory slips of the extensor digiti minimi. Rom J Morphol Embryol. 2014;55(2):487–489.
- El-Badawi MG, Butt MM, al-Zuhair AG, Fadel RA. Extensor tendons of the fingers: arrangement and variations--II. Clin Anat. 1995;8(6):391-8.
- Straus WL, The phylogeny of the human forearm extensors. Hum Biol, 1941;13(1–2):23–50, 204–238.
- Baker J, Gonzalez MH. Snapping wrist due to an anomalous extensor indicis proprius: A Case Report. Hand. 2008;3:363–365.
- Sookur PA, Naraghi AM, Bleakney RR, Jalan R, Chan O, White LM. Accessory Muscles: Anatomy, Symptoms, and Radiologic Evaluation. RadioGraphics.2008;28:481–499.
Swati Tiwari, Anita Mahajan, Rohini Pakhiddey. VARIATIONS IN THE MUSCLES OF THE EXTENSOR COMPARTMENT OF THE FOREARM AND HAND AND ITS CLINICAL SIGNIFICANCE: A CASE REPORT. Int J Anat Res 2015;3(2):1024-1027. DOI: 10.16965/ijar.2015.145