Purpose
Avulsion injury of the flexor digitorum profundus (FDP) tendon has been traditionally
repaired with a pull-out suture over the nail plate. Complication rates with this
method and improvements in anchor design have led to the increased use of bone anchors
to give a rigid all-inside repair. However, the dimensions of the distal phalanx may
limit their use. The primary hypothesis was that 2 micro bone anchors could fit in
either perpendicular or 45° proximally angled positions within each distal phalanx.
A further hypothesis was that 1 mini bone anchor could fit in similar positions in
the distal phalanx.
Methods
Thirty-two fresh frozen fingers were dissected, and the FDP tendon was removed from
the distal phalanx footprint. Two bone anchor types were used, mini and micro sizes,
and inserted at 2 angles, perpendicular and 45° proximally angled. Observations of
dorsal cortex and joint space penetration were recorded. Distal phalanx dimensions
were measured for each finger.
Results
The micro anchors penetrated the dorsal cortex in perpendicular tests in little fingers
only. The micro anchor did not penetrate the joint in any angled tests. The mini bone
anchor penetrated the dorsal cortex in 100% of perpendicular tests and the joint in
63% of angled tests, although none of these included the middle finger.
Conclusions
Two micro bone anchors fit within the distal phalanx in all fingers tested, except
the little finger, when placed in the perpendicular position. At a 45° angle, the
distal phalanx of the little finger can also accommodate micro bone anchors without
any evidence of complication when placed 4 mm from the joint. The mini anchors were
too large to fit in a perpendicular position within the distal phalanx. In the 45°
angled position, the joint was not penetrated by the mini anchor in only middle fingers.
Clinical relevance
The study provides anatomical evidence of the accommodation of micro bone anchors
within the distal phalanx in perpendicular or 45° angled positions for the repair
of FDP tendon avulsion injury.
Key words
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References
- Tendon avulsion injuries of the distal phalanx.Clin Orthop Relat Res. 2006; 445: 157-168
- Surgery of the Hand.4th ed. Lippincott, London1964
- Repair of flexor digitorum profundus to distal phalanx: a biomechanical evaluation of four techniques.J Hand Surg Am. 2011; 36: 1604-1609
- Distal attachment of flexor tendon allograft: a biomechanical study of different reconstruction techniques in human cadaver hands.J Orthop Res. 2013; 31: 1720-1724
- Zone 1 flexor tendon injuries: a review of the current treatment options for acute injuries.J Plast Reconstr Aesthet Surg. 2013; 66: 1023-1031
- Mode of failure for rotator cuff repair with suture anchors identified at revision surgery.J Shoulder Elbow Surg. 2003; 12: 128-133
- Management of dislocations of the elbow in the athlete.Sports Med Arthrosc Rev. 2014; 22: 188-193
- Avulsion injuries of the flexor digitorum profundus tendon.J Am Acad Orthop Surg. 2011; 19: 152-162
- Biomechanical characteristics of suture anchor implants for flexor digitorum profundus repair.J Hand Surg Am. 2014; 39: 256-261
- The effect of mitek anchor insertion angle to attachment of FDP avulsion injuries.J Hand Surg Br. 2006; 31: 292-295
- Extrusion of bone anchor suture following flexor digitorum profundus tendon avulsion injury repair.J Plast Reconstr Aesthet Surg. 2011; 64: 1242-1244
- The Mitek bone anchor: application to the hand, wrist and elbow.J Hand Surg Am. 1994; 19: 853-860
- Anatomy of the flexor digitorum profundus insertion.J Hand Surg Am. 2015; 40: 240-244
- Do the dimensions of the distal phalanges allow suture anchor fixation of the flexor digitorum profundus? A cadaver study.J Hand Surg Eur Vol. 2011; 36: 698-700
- Current practice of primary flexor tendon repair: a global view.Hand Clin. 2013; 29: 179-189
- In vitro studies of a new method of flexor tendon repair.J Hand Surg Br. 1985; 10: 135-141
- Flexor digitorum profundus tendon to bone repair using a multi-strand suture technique.Tech Hand Up Extrem Surg. 2001; 5: 157-160
- Bone suture anchors versus the pullout button for repair of distal profundus tendon injuries: a comparison of strength in human cadaveric hands.J Hand Surg Am. 2001; 26: 489-496
- Flexor digitorum profundus tendon-to bone repair: an ex vivo biomechanical analysis of 3 pullout suture techniques.J Hand Surg Am. 1998; 23: 120-126
- Flexor tendon forces: in vivo measurements.J Hand Surg Am. 1992; 17: 291-298
- Reprint of: The deadman theory of suture anchors: observations along a south Texas fence line.Arthroscopy. 2014; 30: 895-899
- Deadman theory revisited 12.Biomed Mater Eng. 2016; 27: 171-181
- The effect of insertion angle on the pullout strength of threaded suture anchors: a validation of the deadman theory.Arthroscopy. 2014; 30: 900-905
Article info
Publication history
Published online: February 15, 2019
Accepted:
December 11,
2018
Received:
February 24,
2018
Footnotes
No benefits in any form have been received or will be received related directly or indirectly to the subject of this article.
Identification
Copyright
© 2019 by the American Society for Surgery of the Hand. All rights reserved.
