The Range of Pollex-Index Approximations in Opposition

Abstract

Pinch gripping is an evolved hominid attribute: the modification of the first carpo-metacarpal articulation into a sellar type enables an opposable thumb; The pinch, preferentially performed by approximation of the pollex-index fingertip pulps shows variation in range of purchase between these digits depending on the power of grip. This brief report analyzes the area of surface contact between the pollex and index tip in both, light and tight pinch-grip.

The possible role of index anatomy in enhancing the level of efficiency of pinch-grip in opposition is discussed.

Keywords

opposition - index - pollex - pinch grip - purchase area - pulp

Publication History

Article published online:
03 March 2020

• References

• 1 Arunachalam Kumar, The Index digit rotation and opposition evolution, Human Races Monthly, Vol. 1, No.9, 2002
• 2 Rao A & Arunachalam Kumar, Mathematical Analysis of Flexion-Extension of Index Digit, Proceedings of the N.C.B.E., Ed. UC Niranjan, VIII 21, 1998
• 3 Manou J & Arunachalam Kumar, The Rotational Kinetics of Indexth Pollex in Opposition Exercise, 48 A.S.I. National Conference, Manipal, 2001
• 4 Rao A & Arunachalam Kumar A, Opposition Biomechanics: A Community Study, National Conference on Biomedical Engineering, Manipal, 1998
• 5 Rao A & Arunachalam Kumar, Mathematical Analysis of Flexion-Extension of Index Digit, Proceedings of the N.C.B.E., Ed. U C Niranjan, VIII 21, 1998
• 6 Savita S & Arunachalam Kumar, The Thumb-Index Complex Biomechanics in Opposition, XIV Conference of Indian Society of Hand Surgeons, Manipal, 1990
• 7 Arunachalam Kumar, Complementary Rotation of Index in Thumb-Index Opposition Proceedings of the International Conference of Biomechanics & Clinical Kinesiology of Hand & Foot, Eds. Patil K M & Srinivasan H, IIT Madras, 1985