eMedicine Specialties > Plastic Surgery > Hand

Hand, Tendon Lacerations: Flexors

Author: D Glynn Bolitho, MD, PhD, FACS, FRCSC, FCS(SA), Associate Clinical Professor, Department of Plastic Surgery, University of California at San Diego; Private Practice, LaJolla, California
Contributor Information and Disclosures

Updated: Jun 8, 2006

Introduction

Tendon nutrition

The tendon derives its nutrition from the following 2 sources:

  • Diffusion, via the synovial lining sheath Canaliculi pass through the tendon to the surface of the tendon. Movement of fluid into these canaliculi has been demonstrated. This effect is enhanced with digital motion.
  • Perfusion, via the segmental arterial supply The blood supply to the tendon enters distally via the bony insertion and proximally via the vincula. Four vincula, designated V1 to V4, are present. V1 and V2 supply the flexor digitorum superficialis, and V3 and V4 supply the flexor digitorum profundus. They arise at the necks of the proximal and distal phalanges, respectively. In the thumb, the vincula likewise are termed V1 and V2. No flow occurs between adjacent territories of vincula. Presumably, this area is sustained by diffusion through the synovial fluid. The vascular plexus within the tendon occupies the dorsal half. This is important at the time of placement of core sutures during flexor tendon repair.

Logically, diffusion occurs in areas of the tendon that are compressed in flexion, while the other areas are perfused. The flexor digitorum profundus is more dependent on diffusion than the flexor digitorum superficialis.

Tendon healing

A debate persists as to the nature of tendon healing.

  • Extrinsic: The original theory was that sheath fibroblasts were responsible for peritendinous adhesions, and the tendons were healed by this route. This was the theory behind total flexor sheath excision and prolonged immobilization for tendon repairs.
  • Intrinsic: Tendons bathed in synovial fluid were found to heal satisfactorily. The necessary collagen was produced by the tenocytes.

Modern thinking is that tendon healing is initiated by the proliferation of epitendinous cells, which migrate into the defect, forming a "callus" equivalent. Somewhat later, the tenocytes or fibroblasts from within the tendon invade the callus, producing further collagen that realigns to produce the strong tendon. Peritendinous adhesions are not necessary for either healing or nutrition.

Relevant Anatomy

Fibrous flexor sheath

Roughly half of all flexor tendon injuries occur in zone II. The sheath commences at the palmar plate of the metatarsophalangeal (MP) joint with the A1 pulley. A condensation of the palmar aponeurosis results in the so-called palmar aponeurosis (PA) pulley. Where the tendon overlies a joint, the sheath should be sufficiently thin and resilient, resulting in the cruciate (or retinacular) intervals. Where the flexor sheath overlies the phalanges, it is tough and unyielding (annular pulleys A2 and A4). Additional annular pulleys overlie the palmar plates of the MP, proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints, respectively (A1, A3, A5 pulleys). These are continuous with the transverse retinacular ligaments dorsally.

In the thumb, A1 and A2 pulleys are over the palmar plates, and an oblique pulley is over the proximal phalanx. This passes from proximal ulnar to distal radial; in so doing it is virtually an extension of the adductor, which inserts into the sesamoids. The sesamoids, into which insert the 2 heads of flexor pollicis brevis (FPB), lie within the substance of the palmar plate.

In the thumb, similar to the A2 and A4 pulleys in the fingers, the oblique pulley is sacrosanct. Because of the obliquity of the oblique ligament and ulnar takeoff, the A1 pulley in the thumb is best divided radially. This is important when surgical release of a trigger thumb is performed. No pulley should be incised during the course of tendon repair, with exception of the A1, A3, and A5 pulleys. Repair is impossible due to the snug fit and the transverse orientation of the fibers.

Tendon sheath and pulley reconstruction

The issue of sheath reconstruction is controversial, and the decision to undertake this is best individualized after thorough assessment of the patient. The sources of fascia include the adjacent fingers, the dorsal wrist retinaculum, and the foot. For pulley reconstruction, place the tendon graft around the phalanx (sutured to itself), either beneath the extensor tendon for the A2 pulley or superficial to it for A4 pulley reconstruction. A transverse strip of dorsal wrist retinaculum is harvested via a longitudinal incision. If performing a Hunter rod reconstruction, reconstructing the pulley first is often useful before placing the rod to achieve sufficient tension on the pulley. Following suture of the graft, it is rotated around so that a synovial surface overlies the tendon. Such grafts have been demonstrated to continue secreting synovial fluid.

Contraindications

Procedures that involve extension of the tendon are contraindicated for 2 reasons: firstly, the quadriga effect on the other digits is invoked, and secondly, an extension deficit of the involved digit is always present.

Contraindications to 1-stage tendon grafting include less than full ROM, inadequate skin cover, and a hostile bed.

More on Hand, Tendon Lacerations: Flexors

Overview: Hand, Tendon Lacerations: Flexors
Treatment: Hand, Tendon Lacerations: Flexors
Follow-up: Hand, Tendon Lacerations: Flexors
References
[ CLOSE WINDOW ]

References

  1. Aslam A, Afoke A. A new core suture technique for flexor tendon repair: biomechanical analysis of tensile strength and gap formation. J Hand Surg [Br]. Aug 2000;25(4):390-2. [Medline].

  2. Barrie KA, Wolfe SW, Shean C, et al. A biomechanical comparison of multistrand flexor tendon repairs using an in situ testing model. J Hand Surg [Am]. May 2000;25(3):499-506. [Medline].

  3. Bunker TD, Potter B, Barton NJ. Continuous passive motion following flexor tendon repair. J Hand Surg [Br]. Nov 1989;14(4):406-11. [Medline].

  4. Cerovac S, Afoke A, Akali A, McGrouther DA. Early breaking strength of repaired flexor tendon treated with 5- fluorouracil. J Hand Surg [Br]. Jun 2001;26(3):220-3. [Medline].

  5. Chow JA, Thomes LJ, Dovelle S, et al. Controlled motion rehabilitation after flexor tendon repair and grafting. A multi-centre study. J Bone Joint Surg Br. Aug 1988;70(4):591-5. [Medline].

  6. Gelberman RH, Manske PR, Akeson WH, et al. Flexor tendon repair. J Orthop Res. 1986;4(1):119-28. [Medline].

  7. Grobbelaar AO, Hudson DA. Flexor tendon injuries in children. J Hand Surg [Br]. Dec 1994;19(6):696-8. [Medline].

  8. Kleinert HE, Lubahn JD. Current state of flexor tendon surgery. Ann Chir Main. 1984;3(1):7-17. [Medline].

  9. Kleinert HE, Spokevicius S, Papas NH. History of flexor tendon repair. J Hand Surg [Am]. May 1995;20(3 Pt 2):S46-52. [Medline].

  10. Manske PR. Flexor tendon healing. J Hand Surg [Br]. Aug 1988;13(3):237-45. [Medline].

  11. Manske PR. History of flexor tendon repair. Hand Clin. May 2005;21(2):123-7. [Medline].

  12. May EJ, Silfverskiold KL, Sollerman CJ. Controlled mobilization after flexor tendon repair in zone II: a prospective comparison of three methods. J Hand Surg [Am]. Sep 1992;17(5):942-52. [Medline].

  13. Norris SR, Ellis FD, Chen MI, Seiler JG 3rd. Flexor tendon suture methods: a quantitative analysis of suture material within the repair site. Orthopedics. Apr 1999;22(4):413-6. [Medline].

  14. Silfverskiold KL, May EJ, Tornvall AH. Flexor digitorum profundus tendon excursions during controlled motion after flexor tendon repair in zone II: a prospective clinical study. J Hand Surg [Am]. Jan 1992;17(1):122-31. [Medline].

  15. Singer M, Maloon S. Flexor tendon injuries: the results of primary repair. J Hand Surg [Br]. Aug 1988;13(3):269-72. [Medline].

  16. Slattery PG. The modified Kleinert splint in zone II flexor tendon injuries. J Hand Surg [Br]. Aug 1988;13(3):273-6. [Medline].

  17. Small JO, Brennen MD, Colville J. Early active mobilisation following flexor tendon repair in zone 2. J Hand Surg [Br]. Nov 1989;14(4):383-91. [Medline].

  18. Strick MJ, Filan SL, Hile M. Adhesion formation after flexor tendon repair: comparison of two- and four-strand repair without epitendinous suture. Hand Surg. Dec 2005;10(2-3):193-7. [Medline].

  19. Strickland JW. Flexor tendon injuries. Part 5. Flexor tenolysis, rehabilitation and results. Orthop Rev. Mar 1987;16(3):137-53. [Medline].

  20. Strickland JW. Flexor Tendon Injuries: II. Operative Technique. J Am Acad Orthop Surg. Jan 1995;3(1):55-62. [Medline].

  21. Strickland JW. Flexor Tendon Injuries: I. Foundations of Treatment. J Am Acad Orthop Surg. Jan 1995;3(1):44-54. [Medline].

  22. Su BW, Solomons M, Barrow A. A device for zone-II flexor tendon repair. Surgical technique. J Bone Joint Surg Am. Mar 2006;88 Suppl 1 Pt 1:37-49. [Medline].

  23. [Best Evidence] Su BW, Solomons M, Barrow A. Device for zone-II flexor tendon repair. A multicenter, randomized, blinded, clinical trial. J Bone Joint Surg Am. May 2005;87(5):923-35. [Medline].

  24. Tang JB, Wang B, Chen F, et al. Biomechanical evaluation of flexor tendon repair techniques. Clin Orthop. May 2001;(386):252-9. [Medline].

  25. Tang JB, Gu YT, Rice K, et al. Evaluation of four methods of flexor tendon repair for postoperative active mobilization. Plast Reconstr Surg. Mar 2001;107(3):742-9. [Medline].

  26. Vucekovich K, Gallardo G, Fiala K. Rehabilitation after flexor tendon repair, reconstruction, and tenolysis. Hand Clin. May 2005;21(2):257-65. [Medline].

  27. Xie RG, Zhang S, Tang JB. Biomechanical studies of 3 different 6-strand flexor tendon repair techniques. J Hand Surg [Am]. Jul 2002;27(4):621-7. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

flexor tendon injuries, flexor tendon, tendon laceration, flexor tendon laceration, fibrous flexor sheath, tendon sheath, sheath reconstruction, multistrand repair, tensile strength, flexor tendon surgery, flexor laceration, tendon flexor

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

D Glynn Bolitho, MD, PhD, FACS, FRCSC, FCS(SA), Associate Clinical Professor, Department of Plastic Surgery, University of California at San Diego; Private Practice, LaJolla, California
D Glynn Bolitho, MD, PhD, FACS, FRCSC, FCS(SA) is a member of the following medical societies: American College of Surgeons, American Medical Association, American Society for Aesthetic Plastic Surgery, American Society of Maxillofacial Surgeons, American Society of Plastic Surgeons, California Society of Plastic Surgeons, and Royal College of Physicians and Surgeons of Canada
Disclosure: Nothing to disclose.

Medical Editor

Anthony E Sudekum, MD, Consulting Staff, Department of Plastic Surgery, St John's Mercy Health Center of Saint Louis
Anthony E Sudekum, MD is a member of the following medical societies: American College of Surgeons, American Society for Surgery of the Hand, and Missouri State Medical Association
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

David W Chang, MD, FACS, Associate Professor, Department of Plastic Surgery, MD Anderson Cancer Center, The University of Texas
Disclosure: Nothing to disclose.

CME Editor

Nicolas (Nick) G Slenkovich, MD, Practice Director, Colorado Plastic Surgery Center at Swedish Medical Center
Nicolas (Nick) G Slenkovich, MD is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American Medical Association, American Society of Plastic Surgeons, and Colorado Medical Society
Disclosure: Nothing to disclose.

Chief Editor

Jorge I de la Torre, MD, FACS, Professor of Surgery and Physical Medicine and Rehabilitation, Residency Program Director, Division of Plastic Surgery, University of Alabama at Birmingham; Director, Center for Advanced Surgical Aesthetics
Jorge I de la Torre, MD, FACS is a member of the following medical societies: American Association of Plastic Surgeons, American Burn Association, American College of Surgeons, American Medical Association, American Society for Laser Medicine and Surgery, American Society for Reconstructive Microsurgery, American Society of Maxillofacial Surgeons, American Society of Plastic Surgeons, Association for Academic Surgery, and Medical Association of the State of Alabama
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.