In this study, a new nitinol based fixation device was investigated for use in repairing severed digital flexor tendons. The device, composed of superelastic nitinol, is tubular in shape with inward facing tines for gripping tissue. Its cellular structure was designed such that it has a large effective Poisson's ratio, which facilitates a “finger trap” effect. This allows for reduced tendon compression during a resting state (to permit vascular perfusion) and increased compression during loading (to drive the tines into the tissue for gripping). To test the feasibility of using this device for flexor tendon repair, it was tested on cadaver flexor digitorum profundus tendons. The tendons were excised, cut in the region corresponding to a zone II laceration, and repaired using the device. The device was easy to install and did not prevent the tendon from bending. Constant strain rate tensile testing revealed a mean tensile strength of 57.6 ± 7.7 N, with a force of 53.2 ± 7.8 N at a 2 mm gap. This exceeds the suggested primary repair strength of 45 N, which has been proposed as the necessary strength for enabling early mobilization. Although considerable future studies will be needed to determine the suitability of the new repair device for clinical use, this study demonstrates the feasibility of utilizing a tubular, nitinol repair device for flexor tendon fixation.

References

References
1.
Gelberman
,
R. H.
,
Boyer
,
M. I.
,
Brodt
,
M. D.
,
Winters
,
S. C.
, and
Silva
,
M. J.
,
1999
, “
The Effect of Gap Formation at the Repair Site on the Strength and Excursion of Intrasynovial Flexor Tendons. An Experimental Study on the Early Stages of Tendon-Healing in Dogs
,”
J. Bone Joint Surg. Am.
,
81
(
7
), pp.
975
982
.10.1302/0301-620X.81B6.9700
2.
Lee
,
S. K.
,
2012
, “
Modern Tendon Repair Techniques
,”
Hand Clinics
,
28
(
4
), pp.
565
570
.10.1016/j.hcl.2012.08.012
3.
Seiler
,
J. G.
, 3rd,
2001
, “
Flexor Tendon Repair
,”
J. Am. Soc. Surg. Hand
,
1
(
3
), pp.
177
191
.10.1053/jssh.2001.26283
4.
Tanaka
,
T.
,
Amadio
,
P. C.
,
Zhao
,
C.
,
Zobitz
,
M. E.
,
Yang
,
C.
, and
An
,
K. N.
,
2004
, “
Gliding Characteristics and Gap Formation for Locking and Grasping Tendon Repairs: A Biomechanical Study in a Human Cadaver Model
,”
J. Hand Surg.
,
29A
, pp.
6
14
.
5.
Tang
,
J. B.
,
Gu
,
Y. T.
,
Rice
,
K.
,
Chen
,
F.
, and
Pan
,
C. Z.
,
2001
, “
Evaluation of Four Methods of Flexor Tendon Repair for Postoperative Active Mobilization
,”
Plastic Reconstruct. Surg.
,
107
(
3
), pp.
742
749
.10.1097/00006534-200103000-00014
6.
Bogumill
,
G. P.
,
2002
, “
Functional Anatomy of the Flexor Tendon System of the Hand
,”
Hand Surg.
,
7
(
1
), pp.
33
46
.10.1142/S0218810402000790
7.
Boyer
,
M. I.
,
2005
, “
Flexor Tendon Biology
,”
Hand Clinics
,
21
(
2
), pp.
159
166
.10.1016/j.hcl.2004.11.009
8.
Lilly
,
S. I.
, and
Messer
,
T. M.
,
2006
, “
Complications After Treatment of Flexor Tendon Injuries
,”
J. Am. Acad. Orthop. Surg.
,
14
(
7
), pp.
387
396
.
9.
Dy
,
C. J.
,
Hernandez-Soria
,
A.
,
Ma
,
Y.
,
Roberts
,
T. R.
, and
Daluiski
,
A.
,
2012
, “
Complications After Flexor Tendon Repair: A Systematic Review and Meta-Analysis
,”
J. Hand Surg.
,
37
(
3
), pp.
543
551
.10.1016/j.jhsa.2011.11.006
10.
Jaibaji
,
M.
,
2000
, “
Advances in the Biology of Zone II Flexor Tendon Healing and Adhesion Formation
,”
Ann. Plastic Surg.
,
45
(
1
), pp.
83
92
.10.1097/00000637-200045010-00017
11.
Boyer
,
M. I.
,
Meunier
,
M. J.
,
Lescheid
,
J.
,
Burns
,
M. E.
,
Gelberman
,
R. H.
, and
Silva
,
M. J.
,
2001
, “
The Influence of Cross-Sectional Area on the Tensile Properties of Flexor Tendons
,”
J. Hand Surg.
,
26A
, pp.
828
832
.10.1053/jhsu.2001.26661
12.
Khanna
,
A.
,
Friel
,
M.
,
Gougoulias
,
N.
,
Longo
,
U. G.
, and
Maffulli
,
N.
,
2009
, “
Prevention of Adhesions in Surgery of the Flexor Tendons of the Hand: What is the Evidence?
,”
Br. Med. Bull.
,
90
, pp.
85
109
.10.1093/bmb/ldp013
13.
Strick
,
M. J.
,
Filan
,
S. L.
,
Hile
,
M.
,
McKenzie
,
C.
,
Walsh
,
W. R.
, and
Tonkin
,
M. A.
,
2004
, “
Adhesion Formation After Flexor Tendon Repair: A Histologic and Biomechanical Comparison of 2- and 4-Strand Repairs in a Chicken Model
,”
J. Hand Surg.
,
29
(
1
), pp.
15
21
.10.1016/j.jhsa.2003.09.003
14.
Strickland
,
J. W.
,
2000
, “
Development of Flexor Tendon Surgery: Twenty-Five Years of Progress
,”
J. Hand Surg.
,
25
(
2
), pp.
214
235
.10.1053/jhsu.2000.jhsu25a0214
15.
Wolfe
,
S. W.
,
Willis
,
A. A.
,
Campbell
,
D.
,
Clabeaux
,
J.
, and
Wright
,
T. M.
,
2007
, “
Biomechanic Comparison of the Teno Fix Tendon Repair Device With the Cruciate and Modified Kessler Techniques
,”
J. Hand Surg.
,
32
(
3
), pp.
356
366
.10.1016/j.jhsa.2006.10.004
16.
Wong
,
J. K.
,
Alyouha
,
S.
,
Kadler
,
K. E.
,
Ferguson
,
M. W.
, and
McGrouther
,
D. A.
,
2010
, “
The Cell Biology of Suturing Tendons
,”
Matrix Biol.
,
29
(
6
), pp.
525
536
.10.1016/j.matbio.2010.06.002
17.
Aoki
,
M.
,
Manske
,
P. R.
,
Pruitt
,
D. L.
, and
Larson
,
B. J.
,
1994
, “
Tendon Repair Using Flexor Tendon Splints: An Experimental Study
,”
J. Hand Surg.
,
19
(
6
), pp.
984
990
.10.1016/0363-5023(94)90102-3
18.
Gordon
,
L.
,
Dysarz
,
F. A.
,
Venkateswara
,
K. T.
,
Mok
,
A. P.
,
Ritchie
,
R. O.
, and
Rabinowitz
,
S.
,
1999
, “
Flexor Tendon Repair Using a Stainless Steel External Splint. Biomechanical Study on Human Cadaver Flexor Tendons
,”
J. Hand Surgery Br. Eur.
,
24
(
6
), pp.
654
657
.10.1054/jhsb.1999.0287
19.
Gordon
,
L.
,
Tolar
,
M.
,
Rao
,
K. T.
,
Ritchie
,
R. O.
,
Rabinowitz
,
S.
, and
Lamb
,
R. P.
,
1998
, “
Flexor Tendon Repair Using a Stainless Steel Internal Anchor. Biomechanical Study on Human Cadaver Tendons
,”
J. Hand Surg.
,
23
(
1
), pp.
37
40
.10.1016/S0266-7681(98)80215-5
20.
Silfverskiold
,
K. L.
, and
Andersson
,
C. H.
,
1993
, “
Two New Methods of Tendon Repair: An In Vitro Evaluation of Tensile Strength and Gap Formation
,”
J. Hand Surg.
,
18
(
1
), pp.
58
65
.10.1016/0363-5023(93)90246-Y
21.
Gussous
,
Y. M.
,
Zhao
,
C.
,
Amadio
,
P. C.
, and
An
,
K. N.
,
2011
, “
The Resurgence of Barbed Suture and Connecting Devices for Use in Flexor Tendon Tenorrhaphy
,”
Hand (NY)
,
6
(
3
), pp.
268
275
.10.1007/s11552-011-9344-6
22.
Rocchi
,
L.
,
Merolli
,
A.
,
Genzini
,
A.
,
Merendi
,
G.
, and
Catalano
,
F.
,
2008
, “
Flexor Tendon Injuries of the Hand Treated With Tenofix: Mid-Term Results
,”
J. Orthop. Traumatol.
,
9
(
4
), pp.
201
208
.10.1007/s10195-008-0016-4
23.
Su
,
B. W.
,
Protopsaltis
,
T. S.
,
Koff
,
M. F.
,
Chang
,
K. P.
,
Strauch
,
R. J.
,
Crow
,
S. A.
, and
Rosenwasser
,
M. P.
,
2005
, “
The Biomechanical Analysis of a Tendon Fixation Device for Flexor Tendon Repair
,”
J. Hand Surg.
,
30
(
2
), pp.
237
245
.10.1016/j.jhsa.2004.07.020
24.
Su
,
B. W.
,
Raia
,
F. J.
,
Quitkin
,
H. M.
,
Parisien
,
M.
,
Strauch
,
R. J.
, and
Rosenwasser
,
M. P.
,
2006
, “
Gross and Histological Analysis of Healing After Dog Flexor Tendon Repair With the Teno Fix Device
,”
J. Hand Surg.
,
31
(
5
), pp.
524
529
.10.1016/j.jhsa.2006.01.003
25.
Su
,
B. W.
,
Solomons
,
M.
,
Barrow
,
A.
,
Senoge
,
M. E.
,
Gilberti
,
M.
,
Lubbers
,
L.
,
Diao
,
E.
,
Quitkin
,
H. M.
,
Grafe
,
M. W.
, and
Rosenwasser
,
M. P.
,
2006
, “
A Device for Zone-II Flexor Tendon Repair. Surgical Technique
,”
J. Bone Joint Surg. Am.
,
88
(
Suppl 1 Pt 1
), pp.
37
49
.10.2106/JBJS.E.00978
26.
Su
,
B. W.
,
Solomons
,
M.
,
Barrow
,
A.
,
Senoge
,
M. E.
,
Gilberti
,
M.
,
Lubbers
,
L.
,
Diao
,
E.
,
Quitkin
,
H. M.
, and
Rosenwasser
,
M. P.
,
2005
, “
Device for Zone-II Flexor Tendon Repair. A Multicenter, Randomized, Blinded, Clinical Trial
,”
J. Bone Joint Surg. Am.
,
87
(
5
), pp.
923
935
.10.2106/JBJS.C.01483
27.
Hirpara
,
K. M.
,
Sullivan
,
P. J.
, and
O'Sullivan
,
M. E.
,
2010
, “
A New Barbed Device for Repair of Flexor Tendons
,”
J. Bone Joint Surg. Br. Eur.
,
92
(
8
), pp.
1165
1170
.10.1302/0301-620X.92B8.23029
28.
Duerig
,
T. P. A.
, and
Stockel
,
D.
,
1999
, “
An Overview of Nitinol Medical Applications
,”
Mater. Sci. Eng.
,
A273
, pp.
149
160
.
29.
Kujala
,
S.
,
Pajala
,
A.
,
Kallioinen
,
M.
,
Pramila
,
A.
,
Tuukkanen
,
J.
, and
Ryhanen
,
J.
,
2004
, “
Biocompatibility and Strength Properties of Nitinol Shape Memory Alloy Suture in Rabbit Tendon
,”
Biomaterials
,
25
, pp.
353
358
.10.1016/S0142-9612(03)00488-5
30.
Karjalainen
,
T.
,
Goransson
,
H.
,
Viinikainen
,
A.
,
Jamsa
,
T.
, and
Ryhanen
,
J.
,
2010
, “
Nickel-Titanium Wire as a Flexor Tendon Suture Material: An Ex Vivo Study
,”
J. Hand Surg. Eur. Vol.
,
35
(
6
), pp.
469
474
.10.1177/1753193409347421
31.
Peel
,
L. D.
,
2007
, “
Exploration of High and Negative Poisson's Ratio Elastomer-Matrix Laminates
,”
Phys. Status Solidi (b)
,
244
(
3
), pp.
988
1003
.10.1002/pssb.200572717
32.
Sanders
,
D. W.
,
Milne
,
A. D.
,
Dobravec
,
A.
,
MacDermid
,
J.
,
Johnson
,
J. A.
, and
King
,
G. J.
,
1997
, “
Cyclic Testing of Flexor Tendon Repairs: An In Vitro Biomechanical Study
,”
J. Hand Surg.
,
22
(
6
), pp.
1004
1010
.10.1016/S0363-5023(97)80039-1
33.
Vanhees
,
M.
,
Thoreson
,
A. R.
,
Larson
,
D. R.
,
Amadio
,
P. C.
,
An
,
K. N.
, and
Zhao
,
C.
,
2013
, “
The Effect of Suture Preloading on the Force to Failure and Gap Formation After Flexor Tendon Repair
,”
J. Hand Surg. Am.
,
38
(
1
), pp.
56
61
.10.1016/j.jhsa.2012.09.030
34.
Zeplin
,
P. H.
,
Zahn
,
R. K.
,
Meffert
,
R. H.
, and
Schmidt
,
K.
,
2011
, “
Biomechanical Evaluation of Flexor Tendon Repair Using Barbed Suture Material: A Comparative Ex Vivo Study
,”
J. Hand Surg. Am.
,
36
(
3
), pp.
446
449
.10.1016/j.jhsa.2010.11.031
35.
Karjalainen
,
T.
,
He
,
M.
,
Chong
,
A. K.
,
Lim
,
A. Y.
,
Goransson
,
H.
, and
Ryhanen
,
J.
,
2012
, “
Comparison of the Holding Capacity of Round Monofilament, Round Multifilament, and Flat Multifilament Nitinol Suture Loops in Human Cadaveric Flexor Tendon
,”
J. Hand Surg. Eur. Vol.
,
37
(
5
), pp.
459
463
.10.1177/1753193411430034
36.
Lujan
,
T. J.
,
Underwood
,
C. J.
,
Henninger
,
H. B.
,
Thompson
,
B. M.
, and
Weiss
,
J. A.
,
2007
, “
Effect of Dermatan Sulfate Glycosaminoglycans on the Quasi-Static Material Properties of the Human Medial Collateral Ligament
,”
J. Orthop. Res.
,
25
(
7
), pp.
894
903
.10.1002/jor.20351
37.
Lynch
,
H. A.
,
Johannessen
,
W.
,
Wu
,
J. P.
,
Jawa
,
A.
, and
Elliott
,
D. M.
,
2003
, “
Effect of Fiber Orientation and Strain Rate on the Nonlinear Uniaxial Tensile Material Properties of Tendon
,”
ASME J. Biomech. Eng.
,
125
(
5
), pp.
726
731
.10.1115/1.1614819
38.
Dinopoulos
,
H. T.
,
Boyer
,
M. I.
,
Burns
,
M. E.
,
Gelberman
,
R. H.
, and
Silva
,
M. J.
,
2000
, “
The Resistance of a Four- and Eight-Strand Suture Technique to Gap Formation During Tensile Testing: An Experimental Study of Repaired Canine Flexor Tendons After 10 Days of In Vivo Healing
,”
J. Hand Surg.
,
25
(3), pp.
489
498
.10.1053/jhsu.2000.6456
39.
Waitayawinyu
,
T.
,
Martineau
,
P. A.
,
Luris
,
S.
,
Hanel
,
D. P.
, and
Trumble
,
T. E.
,
2008
, “
Comparative Biomechanic Study of Flexor Tendon Repair Using Fiber Wire
,”
J. Hand Surg.
,
33
(5), pp.
701
708
.10.1016/j.jhsa.2008.01.010
40.
Reese
,
S. P.
,
Maas
,
S. A.
, and
Weiss
,
J. A.
,
2010
, “
Micromechanical Models of Helical Superstructures in Ligament and Tendon Fibers Predict Large Poisson's Ratios
,”
J. Biomech.
,
43
(
7
), pp.
1394
1400
.10.1016/j.jbiomech.2010.01.004
41.
Reese
,
S. P.
, and
Weiss
,
J. A.
,
2012
, “
Tendon Fascicles Exhibit a Linear Correlation Between Poisson's Ratio and Force During Uniaxial Stress Relaxation
,”
ASME J. Biomech. Eng.
,
135
(
3
), p.
034501
.10.1115/1.4023134
42.
Griffin
,
M.
,
Hindocha
,
S.
,
Jordan
,
D.
,
Saleh
,
M.
, and
Khan
,
W.
,
2012
, “
An Overview of the Management of Flexor Tendon Injuries
,”
Open Orthop. J.
,
6
, pp.
28
35
.10.2174/1874325001206010028
You do not currently have access to this content.