Abstract

This study investigated the biomechanical effects of thenar muscles (abductor pollicis brevis (APB), superficial head of flexor pollicis brevis (sFPB), opponens pollicis (OPP)) on the transverse carpal ligament formed carpal arch under force application by individual or combined muscles (APB, sFPB, OPP, APB-sFPB, sFPB-OPP, APB-OPP, and APB-sFPB-OPP). In ten cadaveric hands, thenar muscles were loaded under 15% of their respective maximal force capacity, and ultrasound images of the cross section of the distal carpal tunnel were collected for morphometric analyses of the carpal arch. The carpal arch height and area were significantly dependent on the loading condition (p < 0.01), muscle combination (p < 0.05), and their interaction (p < 0.01). The changes to arch height and area were significantly dependent on the muscle combinations (p = 0.001 and p < 0.001, respectively). The arch height and area increased under the loading combinations of APB, OPP, APB-sFPB, APB-OPP, or APB-sFPB-OPP (p < 0.05), but not under the combinations of sFPB (p = 0.893) or sFPB-OPP (p = 0.338). The carpal arch change under the APB-sFPB-OPP or APB-OPP loading was greater than that under the loading of APB-sFPB (p < 0.001). This study demonstrated that thenar muscle forces exert biomechanical effects on the transverse carpal ligament to increase carpal arch height and area, and these increases were different for individual muscles and their combinations.

References

1.
Kung
,
J.
,
Budoff
,
J.
,
Wei
,
M.
,
Gharbaoui
,
I.
, and
Luo
,
Z.
,
2005
, “
The Origins of the Thenar and Hypothenar Muscles
,”
J. Hand Surg. Am.
,
30
(
5
), pp.
475
476
.10.1016/j.jhsb.2005.04.019
2.
Loss
,
J.
, and
Li
,
Z. M.
,
2020
, “
Biometry of Thenar Muscle Origins on the Flexor Retinaculum
,”
Clin. Anat.
, 33(8), pp.
1176
1180
.10.1002/ca.23558
3.
Fuss
,
F. K.
, and
Wagner
,
T. F.
,
1996
, “
Biomechanical Alterations in the Carpal Arch and Hand Muscles After Carpal Tunnel Release: A Further Approach Toward Understanding the Function of the Flexor Retinaculum and the Cause of Postoperative Grip Weakness
,”
Clin. Anat.
,
9
(
2
), pp.
100
108
.10.1002/(SICI)1098-2353(1996)9:2<100::AID-CA2>3.0.CO;2-L
4.
Mathur
,
K.
,
Pynsent
,
P.
,
Vohra
,
S.
,
Thomas
,
B.
, and
Deshmukh
,
S.
,
2004
, “
Effect of Wrist Position on Power Grip and Key Pinch Strength Following Carpal Tunnel Decompression
,”
J. Hand Surg. Am.
,
29
(
4
), pp.
390
392
.10.1016/J.JHSB.2004.02.012
5.
Gellman
,
H.
,
Kan
,
D.
,
Gee
,
V.
,
Kuschner
,
S. H.
, and
Botte
,
M. J.
,
1989
, “
Analysis of Pinch and Grip Strength After Carpal Tunnel Release
,”
J. Hand Surg. Am.
,
14
(
5
), pp.
863
864
.10.1016/S0363-5023(89)80091-7
6.
Mhanna
,
C.
,
Marquardt
,
T. L.
, and
Li
,
Z.-M.
,
2016
, “
Adaptation of the Transverse Carpal Ligament Associated With Repetitive Hand Use in Pianists
,”
PLoS One
,
11
(
3
), p.
e0150174
.10.1371/journal.pone.0150174
7.
Shen
,
Z. L.
, and
Li
,
Z.-M.
,
2013
, “
Biomechanical Interaction Between the Transverse Carpal Ligament and the Thenar Muscles
,”
J. Appl. Physiol.
,
114
(
2
), pp.
225
229
.10.1152/japplphysiol.01273.2012
8.
Li
,
Z. M.
,
Masters
,
T. L.
, and
Mondello
,
T. A.
,
2011
, “
Area and Shape Changes of the Carpal Tunnel in Response to Tunnel Pressure
,”
J. Orthop. Res.
,
29
(
12
), pp.
1951
1956
.10.1002/jor.21468
9.
Li
,
Z.-M.
,
Tang
,
J.
,
Chakan
,
M.
, and
Kaz
,
R.
,
2009
, “
Carpal Tunnel Expansion by Palmarly Directed Forces to the Transverse Carpal Ligament
,”
ASME J. Biomech. Eng.
,
131
(
8
), p. 081011.10.1115/1.3148469
10.
Li
,
Z.-M.
,
Gabra
,
J. N.
,
Marquardt
,
T. L.
, and
Kim
,
D. H.
,
2013
, “
Narrowing Carpal Arch Width to Increase Cross-Sectional Area of Carpal Tunnel—a Cadaveric Study
,”
Clin. Biomech.
,
28
(
4
), pp.
402
407
.10.1016/j.clinbiomech.2013.02.014
11.
Marquardt
,
T. L.
,
Evans
,
P. J.
,
Seitz
,
W. H.
, Jr.
, and
Li
,
Z. M.
,
2016
, “
Carpal Arch and Median Nerve Changes During Radioulnar Wrist Compression in Carpal Tunnel Syndrome Patients
,”
J. Orthop. Res.
,
34
(
7
), pp.
1234
1240
.10.1002/jor.23126
12.
Gartsman
,
G. M.
,
Kovach
,
J. C.
,
Crouch
,
C. C.
,
Noble
,
P. C.
, and
Bennett
,
J. B.
,
1986
, “
Carpal Arch Alteration After Carpal Tunnel Release
,”
J. Hand Surg. Am.
,
11
(
3
), pp.
372
374
.10.1016/S0363-5023(86)80144-7
13.
Richman
,
J. A.
,
Gelberman
,
R. H.
,
Rydevik
,
B. L.
,
Hajek
,
P. C.
,
Braun
,
R. M.
,
Gylys-Morin
,
V. M.
, and
Berthoty
,
D.
,
1989
, “
Carpal Tunnel Syndrome: Morphologic Changes After Release of the Transverse Carpal Ligament
,”
J. Hand Surg. Am.
,
14
(
5
), pp.
852
857
.10.1016/S0363-5023(89)80089-9
14.
Viegas
,
S. F.
,
Pollard
,
A.
, and
Kaminksi
,
K.
,
1992
, “
Carpal Arch Alteration and Related Clinical Status After Endoscopic Carpal Tunnel Release
,”
J. Hand Surg. Am.
,
17
(
6
), pp.
1012
1016
.10.1016/S0363-5023(09)91048-6
15.
Kline
,
S.
, and
Moore
,
J.
,
1992
, “
The Transverse Carpal Ligament. An Important Component of the Digital Flexor Pulley System
,”
J. Bone Jt. Surg. Am.
,
74
(
10
), pp.
1478
1485
.10.2106/00004623-199274100-00006
16.
Li
,
Z.-M.
,
2005
, “
Gender Difference in Carpal Tunnel Compliance
,”
J. Musculoskelet. Res.
,
09
(
03
), pp.
153
159
.10.1142/S0218957705001527
17.
Garcia-Elias
,
M.
,
Sanchez-Freijo
,
J. M.
,
Salo
,
J. M.
, and
Lluch
,
A. L.
,
1992
, “
Dynamic Changes of the Transverse Carpal Arch During Flexion-Extension of the Wrist: Effects of Sectioning the Transverse Carpal Ligament
,”
J. Hand Surg. Am.
,
17
(
6
), pp.
1017
1019
.10.1016/S0363-5023(09)91049-8
18.
Lakshminarayanan
,
K.
,
Shah
,
R.
, and
Li
,
Z.-M.
,
2020
, “
Morphological and Positional Changes of the Carpal Arch and Median Nerve Associated With Wrist Deviations
,”
Clin. Biomech.
,
71
, pp.
133
138
.10.1016/j.clinbiomech.2019.10.024
19.
Brand
,
P. W.
,
Beach
,
R.
, and
Thompson
,
D.
,
1981
, “
Relative Tension and Potential Excursion of Muscles in the Forearm and Hand
,”
J. Hand Surg. Am.
,
6
(
3
), pp.
209
219
.10.1016/S0363-5023(81)80072-X
20.
Gupta
,
S.
, and
Michelsen-Jost
,
H.
,
2012
, “
Anatomy and Function of the Thenar Muscles
,”
Hand Clin.
,
28
(
1
), pp.
1
7
.10.1016/j.hcl.2011.09.006
21.
Jan
,
S. V. S.
, and
Rooze
,
M.
,
1992
, “
The Thenar Muscles
,”
Surg. Radiol. Anat.
,
14
(
4
), pp.
325
329
.10.1007/BF01794759
22.
Yao
,
Y.
,
Grandy
,
E.
,
Evans
,
P. J.
,
Seitz
,
W. H.
, Jr.
, and
Li
,
Z. M.
,
2018
, “
Enhancement in Median Nerve Mobility During Radioulnar Wrist Compression in Carpal Tunnel Syndrome Patients
,”
Clin. Biomech. (Bristol, Avon)
,
60
, pp.
83
88
.10.1016/j.clinbiomech.2018.10.017
23.
Xiu
,
K.-H.
,
Kim
,
J.-H.
, and
Li
,
Z.-M.
,
2010
, “
Biomechanics of the Transverse Carpal Arch Under Carpal Bone Loading
,”
Clin. Biomech.
,
25
(
8
), pp.
776
780
.10.1016/j.clinbiomech.2010.05.011
24.
Garcia-Elias
,
M.
,
An
,
K. N.
,
Cooney
,
W. P.
,
Linscheid
,
R. L.
, and
Chao
,
E. Y.
,
1989
, “
Transverse Stability of the Carpus. An Analytical Study
,”
J. Orthop. Res.
,
7
(
5
), pp.
738
743
.10.1002/jor.1100070516
25.
Stecco
,
C.
,
Macchi
,
V.
,
Lancerotto
,
L.
,
Tiengo
,
C.
,
Porzionato
,
A.
, and
De Caro
,
R.
,
2010
, “
Comparison of Transverse Carpal Ligament and Flexor Retinaculum Terminology for the Wrist
,”
J. Hand Surg. Am.
,
35
(
5
), pp.
746
753
.10.1016/j.jhsa.2010.01.031
26.
Fahrer
,
M.
,
1977
, “
On the Form and Function of the Abductor Pollicis Brevis Muscle
,”
ANZ J. Surg.
,
47
(
2
), pp.
243
247
.10.1111/j.1445-2197.1977.tb04279.x
27.
Sucher
,
B. M.
,
Hinrichs
,
R. N.
,
Welcher
,
R. L.
,
Quiroz
,
L.-D.
,
Laurent
,
B. F. S.
, and
Morrison
,
B. J.
,
2005
, “
Manipulative Treatmentof Carpal Tunnel Syndrome: Biomechanical and Osteopathic Intervention to Increase the Length of the Transverse Carpal Ligament: Part 2—Effect of Sex Differences and Manipulative “Priming
”,”
J. Am. Osteopath. Assoc.
,
105
(
3
), pp.
135
143
.https://pubmed.ncbi.nlm.nih.gov/15863733/
28.
Buchberger
,
W.
,
Judmaier
,
W.
,
Birbamer
,
G.
,
Lener
,
M.
, and
Schmidauer
,
C.
,
1992
, “
Carpal Tunnel Syndrome: Diagnosis With High-Resolution Sonography
,”
AJR. Am. J. Roentgenol.
,
159
(
4
), pp.
793
798
.10.2214/ajr.159.4.1529845
29.
Brett
,
A. W.
,
Oliver
,
M. L.
,
Agur
,
A. M.
,
Edwards
,
A. M.
, and
Gordon
,
K. D.
,
2014
, “
Quantification of the Transverse Carpal Ligament Elastic Properties by Sex and Region
,”
Clin. Biomech.
,
29
(
6
), pp.
601
606
.10.1016/j.clinbiomech.2014.05.003
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