FLEXOR TENDON LACERATION

Introduction

Flexor tendon lacerations are some of the most common injuries managed by hand surgeons. These injuries—which can occur at the digits, palm, wrist, or forearm level. Flexor tendon lacerations typically result from penetrating trauma to the palmar surface of the wrist, palm or digits that reach the flexor tendon(s), such as from falling into a mirror or window. Depending on the location of tendon involvement, the patient may be unable to flex the affected digit(s) or thumb, thus causing a severe impairment to hand function. Several aspects of flexor tendon laceration management are controversial, but primary repair is generally regarded as the treatment of choice for most injuries that require surgery. Due to the nuances of managing these injuries, it is essential for surgeons to have a complete understanding of the decision-making process and to conduct an appropriate workup before making treatment decisions to increase the chances of a positive outcome.^1-3

Pathophysiology

A flexor tendon laceration occurs when a traumatic injury to the volar side of the wrist, palm, fingers or thumb penetrates the skin deep enough to lacerate the flexor tendon(s).^1,2
The penetrating trauma can be accidental or intentional, and often involves metal or glass, such as from a fall through a plate glass window or mirror, handling broken glass, etc.^1,2

Related Anatomy

Flexor digitorum profundus (FDP) tendon
- Functions as the primary flexor of the distal interphalangeal (DIP) joint and assists with proximal interphalangeal (PIP) joint and metacarpophalangeal (MP) flexion
- Flexor digitorum superficialis (FDS) tendon
  - Functions as the primary flexor of the PIP joint and assists with MP flexion
  - Flexor pollicis longus (FPL) tendon
    - The most radial structure within the carpal tunnel and is the primary flexor of the thumb
    - Flexor carpi radialis (FCR) tendon
      - Inserts on the base of the index metacarpal and serves as a primary wrist flexor
      - Flexor carpi ulnaris (FCU) tendon
        Inserts on the pisiform, hook of hamate, and base of the little metacarpal, and serves as the other primary wrist flexor
        Flexor tendon sheaths
        Protect the tendons in the wrist and fingers, with considerable level of variation in communicating patterns between the two types of sheaths, as seen in the diagnostic guides for hand infections²
        Pulley system
        Annular and cruciate pulleys
        Pulleys are a condensation of dense connective tissue and segmentally distributed along the digital sheath that serve to restrain the tendons from bowstringing and to accommodate maximum mechanical efficiency of tendon excursion.²
        There are five annular pulleys (A1, A2, A3, A4, and A5) and three cruciate pulleys (C1, C2 and C3).
        Camper’s chiasm is a split of the FDS tendon over the distal proximal phalanx and PIP joint. This split allows the FDP to pass through the more superficial FDS as it continues to the tip of the finger.
        Flexor tendon lacerations are typically classified based on location in one of the following five zones:
        Zone I: distal to the FDS insertion
        Only the FDP is susceptible to injury in this region
Zone II: from the FDS insertion to the distal palmar crease
- The FDS and FDP are close together, and both are therefore susceptible to injury in this region. This area is often called “no-man’s land” because of the small tight fibro osseous tunnel in this area and difficulties associated with flexor tendon repair in this area.
Zone III: from the distal end of the transverse carpal ligament to the distal volar palmar crease
- Typically involve injuries to multiple structures and multiple digits, as this zone contains the tendons and neurovascular structures to all digits
Zone IV: over the transverse carpal ligament
- Injuries are uncommon in this zone because of the protection provided by the thick transverse carpal ligament
Zone V: from the transverse carpal ligament to the forearm
- Less protected than zone IV, and therefore more prone to injury
- Often associated with concomitant neurovascular injury³
- The majority of flexor tendon lacerations occur in zone II, with one study finding the relative distribution of these injuries in the fingers to be: 12.7% in zone I, 59.1% in zone II, 6.8% in zone III, 0.6% in zone IV, and 20.7% in zone V.⁴ This was also found to be the case in the pediatric population, with the little finger being most commonly injured.²
- The flexor tendons of the index and little fingers are most likely to be injured in zone II, whereas the long finger is most likely to be injured in zone V.¹
The little and index fingers are the most vulnerable digits to tendon lacerations.⁵

Overall Incidence

Hand injuries have been found to account for 14-30% of all injuries treated in the ED. Of these, ~42% are fractures and ~29% are tendon injuries.⁶
The annual incidence of flexor tendon injuries is 30-42 per 100,000 persons in the developed world. This rate appears to be gradually decreasing, in part because workplace injuries have become less frequent due to improved safety measures.^4,7
The average age of patients who sustain flexor tendon injuries is 35 years, and the male-to-female ratio has been found to range from 3:1 to 6:1.¹
Flexor tendon injuries are less common in the pediatric population, with one report finding an annual incidence of 3.6 per 100,000 children (<16 years). The peak incidence in this population is 7 years, and the boy-to-girl ratio is 3:1.²
Work-related accidents have been found to account for ~25% of flexor tendon injuries.¹

Related Injuries

Metacarpal fracture
Phalangeal fracture
Flexor sheath injury
Pulley system injury
Neurovascular injury

ICD-10 Codes

Diagnostic Guide Name

FLEXOR TENDON LACERATION

ICD 10 Diagnosis, Single Code, Left Code, Right Code and Bilateral Code

DIAGNOSIS	SINGLE CODE ONLY	LEFT	RIGHT	BILATERAL (If Available)
FLEXOR TENDON LACERATION (FOREARM LEVEL)
- INDEX		S56.122_	S56.121_
- MIDDLE		S56.124_	S56.123_
- RING		S56.126_	S56.125_
- LITTLE		S56.128_	S56.127_
- THUMB		S56.022_	S56.021_
FLEXOR TENDON LACERATION (WRIST AND HAND LEVEL)
- INDEX		S66.121_	S66.120_
- MIDDLE		S66.123_	S66.122_
- RING		S66.125_	S66.124_
- LITTLE		S66.127_	S66.126_
- THUMB		S66.022_	S66.021_

Instructions (ICD 10 CM 2020, U.S. Version)

THE APPROPRIATE SEVENTH CHARACTER IS TO BE ADDED TO EACH CODE FROM CATEGORY S56 AND S66

A - Initial Encounter

D - Subsequent Routine Healing

S - Sequela

ICD-10 Reference

Reproduced from the International statistical classification of diseases and related health problems, 10th revision, Fifth edition, 2016. Geneva, World Health Organization, 2016 https://apps.who.int/iris/handle/10665/246208

Clinical Presentation Photos and Related Diagrams

Right Flexor Pollicis Longus (FPL) Laceration with intact Left FPL
Right long finger FDP laceration at the DIP joint level (arrow) with lack of DIP flexion (insert)
Right index finger laceration of the FDP and partial FDS laceration
Three week old right fifth flexor tendon laceration. Note patient has already learned to use finger trapping (insert) to flexion the fifth finger
Left ring and little finger FDP and FDS tendon lacerations in "No-Man's land". Note the loss of the normal resting finger posture
Right little finger FDP laceration with probable intact or partially intact FDS (arrow)

Basic Science Photos and Related Diagrams

Flexor Tendon Repair Suture Techniques

Basic Science Pics

A Kessler core suture (Tajima & Modified Kessler in inserts) for flexor tendon repair. A 3-O or 4-O braided synthetic permanent suture is one acceptable suture choice for the the core suture
A Modified Bunnell core suture for flexor tendon repair. A 3-O or 4-O braided synthetic permanent suture is one acceptable suture choice for the the core suture.
A Savage core suture for flexor tendon repair. A 3-O or 4-O braided synthetic permanent suture is one acceptable suture choice for the the core suture
A Strickland core suture for flexor tendon repair. A 3-O or 4-O braided synthetic permanent suture is one acceptable suture choice for the the core suture
A Krachow core suture for flexor tendon repair. Usually for large tendons like the biceps but possibly useful for a FCR laceration. A 3-O or 4-O braided synthetic permanent suture is one acceptable suture choice for the the core suture
A separate second simple running for the edge or epitenon part of the flexor tendon repair is very important. This simple running suture is appropriate suture technique for this repair . A 6-O nylon is one acceptable suture for the epitenon repair
A separate second simple locking running for the edge or epitenon part of the flexor tendon repair is very important. This simple running suture is appropriate suture technique for this repair . A 6-O nylon is one acceptable suture for the epitenon repair
A separate second Cross-Silferskiold running for the edge or epitenon part of the flexor tendon repair is very important. This simple running suture is appropriate suture technique for this repair . A 6-O nylon is one acceptable suture for the epitenon repair

Pathoanatomy Photos and Related Diagrams

Flexor Tendon Zones of Injury and Flexor Pulley Anatomy

Flexor Tendon Zones of injury for fingers, thumb, hand and wrist. The most difficult repairs are those done in Zone II where the fibro osseous tunnel of the flexor tendon sheath is narrow and tight
This diagram highlights the vascular supply and components of the flexor tendon sheath. The three cruciate pulleys (C1-3), the five annular pulleys (A1-A5) and the palmar aponeurotic pulley (PA) are shown. The A2 and A4 pulleys are the biomechanically the most important pulleys. During flexor tendon surgery, Tang(ref14) has shown that the A2 pulley can be 50% excised or vented and the A4 can be 100% vented if needed for tendon excursion if the other parts of the sheath are intact

Finger Flexor Tendon Anatomy

A. Extensor tendon; B. Central slip; C. Oblique fibers of dorsal aponeurosis; D. Lateral slip; E. Conjoined lateral band; F. Triangular ligament; G. Terminal extensor tendon; H. Flexor digitorum profundus; I. Volar plate; J. A-2 & A-4 pulleys; K. Flexor digitorum superficialis; L. Transverse retinaculum; M. Accessory collateral ligament; N. Proper collateral ligament
H. Flexor digitorum profundus; I. Volar plate; J. A-2 & A-4 pulley; K. Flexor digitorum superficialis; L. Transverse retinaculum

Symptoms

History of penetrating trauma, e.g. laceration, to the digits, hand or wrist

Pain at the site of injury

Impaired finger and/or wrist flexion

Typical History

The typical patient is a 35-year-old, right-handed male who injured himself after trying to break up an altercation at an outdoor party he was hosting. The man was carrying on with friends when he noticed a couple verbally fighting and the situation escalating quickly, which led him to walk over to intervene. He asked the couple if everything was all right and requested that they take it inside, but the other man grew starting acting unruly. When he turned his back, the irate man forcefully pushed him into a closed plate glass door. The man instinctively put his hands up to brace him from the impact, and the door shattered as he made contact with it. This resulted in a clean cut across the top of his right palm and a zone II laceration of both the FDS and FDP of his index finger. The wound was immediately wrapped with a temporary compression bandage.

Positive Tests, Exams or Signs

Work-up Options

Treatment Options

Treatment Goals

Repair the tendon laceration and rehabilitate the patient’s hand function.
The primary goal of flexor tendon repair is to create a strong, stable repair that promotes intrinsic healing and allows the tendon to glide smoothly.^3,8Surgical repair should minimize gapping at the repair site, prevent the formation of adhesions, minimize extrinsic scarring, utilize easy suture placement with secured knots and smooth end-to-end tendon apposition, and avoid injury to the tendon vasculature.^3,8,9

Conservative

A conservative approach may be used for some partial flexor tendon lacerations, but there is still some debate on this topic, with opinions being divided as to whether or not surgery is still preferable.²
Although agreement is also lacking on the specific cut-off, most experts advise for nonoperative treatment if the partial laceration involves <50-60% of the flexor tendon’s cross-sectional area. When indicated, a typical conservative treatment protocol includes suturing the laceration, wound care, and early ROM exercises.^2,10

Operative

Surgical repair is generally regarded as the mainstay of treatment for flexor tendon lacerations, and a variety of surgical options are available; however, there are currently no clinical practice guidelines, quality measures, or a gold standard intervention for flexor tendon repair.^2,3,9
One of the primary indications for surgical repair is substantial tendon involvement. As stated above, the exact cut-off to indicate surgery has not been agreed upon, but complete lacerations and those that involve greater than 50% of the flexor tendon’s cross-sectional area are generally considered good candidates for surgical repair. The other major indication for a primary or delayed end-to-end tendon repair is a clean-cut tendon injury or tendon injury in a wound that can be converted to a clean-cut wound with limited damage to peritendinous tissues.^2,10 Absolute contraindications to flexor tendon repair are severe contamination, signs of infection, and long defects of the flexor tendons. Serious crush injuries, severe wound contamination, and extensive destruction of pulleys and tendon structures are also contraindications for repair, while loss of soft tissue coverage over the tendon or the presence of fractures are borderline contraindications. Initial surgical treatment may have to be directed at controlling infection if fixation of fracture and obtaining appropriate soft tissue coverage before the flexor tendons can safely be reconstructed.
- Simultaneous injuries to the nerves and arteries are common and are not a contraindication for primary repair.²
Primary end-to-end flexor tendon repair is performed immediately after wound cleaning and debridement, usually within several to 24 hours after the inciting trauma.²
For ASSH's Hand-e Surgical Video of State of Art of Flexor Tendon Repair by Lalonde:
There are some nuances to each anatomic zone that must be considered when deciding on the optimal surgical approach:
- Zone I: these injuries involve the FDP tendon alone, and the attached vincula on the proximal stump often prevents proximal retraction of the tendon; in very distal lacerations where repair is not possible, the tendon may be repaired by a Bunnell pullout suture over a button, or by placing a suture anchor into the distal phalanx. The FDP should not be shortened more than 1 cm
- Zone II: because of the close proximity of the FDP and FDS tendons, adhesion formation between them is common; one way to reduce the risk for adhesion is by repairing only one slip of the FDS, but most surgeons recommend repairing both tendons if possible
- Zone III: direct tendon repair, which is associated with good results and less risk of adhesion formation because of improved vascularity and more space for the increased bulk of the tendon repair
- Zone IV: direct tendon repair that also includes repair of the transverse carpal ligament; risk for adhesion formation is low
- Zone V: should be treated urgently with direct tendon repair because of the proximity of the neighboring neurovascular structures and retraction of the tendons, i.e. associated neurovascular injuries may make repair more urgent³
Deciding what type of incision to use should be based the orientation of the wound, the preference of the surgeon, and the laceration’s location. A Brunner type of zig-zag incision may be used in the fingers and palm, which allows for exposure without longitudinal incisions over flexion creases in the finger. Transverse incisions at the corners of the zig-zag may also be used as a V-to-Y advancement to assist in lengthening the wound and closure. A mid-lateral incision is an alternative to the Brunner incision that avoids crossing the volar surface of the digit.³
Suture technique, suture material, and suture configuration are all essential for achieving optimal strength in tendon repairs. Surgeons must therefore understand the mechanical properties of different types of suture materials and repair techniques to increase the chances of a positive outcome.¹¹The number of core suture strands that cross the repair site is more important than the number of grasping loops, and current literature has shown that multiple core suture strands (2-4) crossing the repair site result in a stronger repair that can usually tolerate early active ROM rehabilitation protocols. Repair strength can be further increased with higher suture caliber and stiffer suture materials. Adding an epitendinous stitch also improves the biomechanical strength of repairs, minimizes gapping, and helps reduce cross-sectional area, which in turn decreases gliding friction. The epitendinous stitch also increases the repair strength.⁹
Wide-awake flexor tendon repair may also be considered, as it allows for intraoperative assessment of repair gaps, reduces the need for postoperative tenolysis, and facilitates postoperative early active ROM.
For ASSH's Hand-e Surgical Video of Awake Flexor Tendon Repair with Cross Locked Suture by Tuckman:
Flexor tendon reconstruction indications are somewhat controversial, but it is generally accepted as an option when primary repair has failed, when a flexor tendon injury is missed, and for crush injuries, contaminated injuries, open fractures, skin deficiencies, and considerably scarred digits. The ability of patients to comply with an extensive rehabilitation program is also an absolute prerequisite.¹²
Delayed primary end-to-end repair is performed days to three weeks after trauma, after initial irrigation, debridement, and closure of the wound at the time of injury. Delayed repair needs to be performed within three weeks post-injury, as surgery is not typically possible beyond this timeframe because of proximal tendon swelling and tendon retraction.^2,3Whenever possible, acutely lacerated flexor tendons should be treated primarily or during the delayed primary stage. In an ideal situation, the patient is seen in the outpatient center soon after injury. There, an experienced hand surgeon should re-evaluate the patient, provide appropriate patient education, and make a surgical plan for flexor tendon repair.²

Treatment Photos and Diagrams

Flexor Tendon Repair

Right index FDP and FDS lacerations (arrow) with incision outlined for repair
Right index FDP and FDS lacerations with incision open. A slip of cruciate pulley is seen (1) and partial laceration of FDS noted (2)
Right index FDP (1) has been retrieved and needle is preventing FDP retraction (2). Palm incision (3) was used to assist FPD retrieval
DIP passively flexed to express the distal FDP (2) into the surgical site. Proximal FDP (3)
Tiny clamp (1) gently holding proximal FDP so tendon will not have to be grasped repeatedly with a forceps. Tapered needle with braided permanent 3O suture (2) has been placed in the radial aspect of the FDP tendon. This the first core suture pass for a modified Kessler suture
First core suture with a modified Kessler suture is in place (1). Second core suture (2) being placed in the radial aspect of the FDP tendon. Second needle placed carefully to avoid damaging the first suture
Final pass of the needle for the second core suture (1) being placed in the proximal FDP
Tiny clamp (1) gently holding distal FDP so tendon will not have to be grasped repeatedly. Small FDS laceration being tidied up with 6O nylon suture (2). Modified Kessler core sutures in proximal FDP (3)
Core sutures in distal FDP (1) and proximal FDP (2)
Dorsal peripheral edge suture (arrow) being placed before core sutures tied
Modified Kessler core sutures being tied (1)
Core suture tied but not cut completely. Volar edge suture (6O nylon) being placed (1). Needle (2) blocking FDP retraction still in place
Ringer finger FDS & FDP laceration. FDP (1) has been retrieved and brought through FDS slips forming the chiasma of Camper (2)
Complication: Left long finger scarred FDP repair with poor active range of motion
Complication: Right finger FDP repair with rupture A2 pulley repair

CPT Codes for Treatment Options

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Common Procedure Name

Flexor tendon repair no man's land

CPT Description

Flexor tendon repair or advancement single in no man's land primary each tendon

CPT Code Number

26356

Common Procedure Name

Flexor tenolysis

CPT Description

Tenolysis, simple, flexor tendon; palmar or finger, single, each tendon

CPT Code Number

26440

Common Procedure Name

Pulley reconstruction with graft

CPT Description

Reconstruction of tendon pulley, each tendon; with local tissues with tendon or fascial graft (includes obtaining graft)

CPT Code Number

26502

Common Procedure Name

Flexor tenolysis

CPT Description

Tenolysis, flexor or extensor tendon, forearm and/or wrist, single each tendon

CPT Code Number

25295

CPT Code References

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Hand Therapy

As with many other aspects of flexor tendon repair management, there is some controversy regarding the optimal approach for postoperative rehabilitation. The three general tendon repair rehabilitation protocols are complete immobilization, early active ROM, and controlled passive ROM only. Surgeons should base their decision on the quality of the repair and the likelihood of patient compliance:¹All protocols use a dorsal blocking splint with the wrist in 30° of flexion and MP joints in 70° of flexion.³Complete immobilization is typically only prescribed to children and adults that demonstrate unreliability in following postoperative instructions.³Early active ROM protocols involve digital “place-and-hold” exercises and have been found to be as safe and easier to perform than passive ROM protocols.¹³In noncompliant adults and those unable to comprehend an early active protocol, passive ROM may be prescribed. In the Duran protocol, the extremity is kept splinted and the patient or therapist uses their uninvolved hand to passively range the finger to promote tendon gliding.³

Complications

Two most common complications after repair are adhesion formation and joint contracture
Lumbrical-plus finger
Pulley failure
Bowstringing
Quadrigia
Swan-neck deformity
Trigger finger
Tendon entrapment
Tendon rerupture
Infection
In partial tendon lacerations, the incidence of complications is related to the degree of laceration of the cross-sectional area of the tendon. Strangely, complications are more significant when lesser lacerations are repaired, while for greater lacerations, complications are more common when no repair is performed.²

Outcomes

It is difficult to investigate outcomes of flexor tendon lacerations because of the sheer diversity of available management protocols, and there is no Level I clinical evidence showing one repair or rehabilitation regimen to be superior to another; however, research generally suggests that most patients treated with surgical repair experience positive outcomes.^1,2,14,15
The outcomes of flexor tendon repair over a 20-year period were reviewed, and it was found that ~75% of patients experienced good or excellent recovery of function. Additional observations included the following: Primary or delayed primary repairs were prioritized over secondary repair by all surgeons. Early tendon motion—either active, passive, or combined—was advocated in all cases by surgeons and participating therapists, except for children. There has been a gradual but clear shift from using 2-strand core suture repairs to stronger 4- or 6-strand surgical repairs. Use of stronger surgical repairs has lowered rupture rates, but in most reports, ruptures have not been eliminated, with 2-4% rupture rates frequently recorded. More surgeons have recently adopted some type of early active ROM regimen together with use of stronger surgical tendon repairs. New tendon repair materials like fiberwire have emerged and surgeons have reported good functional outcomes and fewer repair ruptures with these repairs.¹⁴
A systematic review and meta-analysis on flexor tendon repair outcomes found that repairs using epitendinous sutures had an 84% lower chance of reoperation than repairs without it.¹⁶
Outcomes after flexor tendon reconstruction are generally found to be inferior to those of primary flexor tendon repair.¹²

Video

Right index laceration in "No-Man's Land" with no signs of active flexion of the PIP or DIP joints. Some MP flexion secondary to intact intrinsic muscles.

Another right index laceration with a cut FDP and partially intact FDS. Note some intact PIP joint active flexion

Laceration of right long finger (arrow) could have easily cut the flexor tendons but note normal active flexion at all joints

Note the use of the passive tenodesis affect to immediately check the range of motion after index flexor tendon repairs

Key Educational Points

Open traumatic wounds with a deep, narrow traumatic laceration should raise suspicion of concomitant tendon injuries.²
There have been some significant advances in suture technique and rehabilitation protocols for flexor tendon lacerations, but there is still a need for high-level efficacy studies to evaluate whether results from experimental surgical studies and rehabilitation studies can be translated to clinical care.³
Although the management of partial tendon lacerations has evolved over the past 50 years, much more research is needed to create a consensus in different aspects of treating these injuries.²
Repairing zone II flexor tendon lacerations is extremely difficult, with the region being referred to as “no man’s land” by Dr. Sterling Bunnell in 1948. Consequently, both the process and method of repair have changed over the past decade as surgeons strive to optimize postoperative outcomes.⁸
Tendon repairs in the digital sheath area are technically demanding and controversial, but the guiding treatment principle is not to narrow the injured or opened sheath and not to compress the repaired tendons. Closure of the injured sheath therefore may not be necessary unless the opening is long.²However, the integrity of the A2 and A4 pulleys is necessary.
The physical examination is the most important component of treatment management, and it should include evaluation of the resting posture of the hand, as loss of the normal cascade with extension of the injured digit is suggestive of a flexor tendon injury. Loss of the tenodesis effect or an abnormal forearm compression test will confirm this suspicion.³
Routine radiographsare often performed to detect the presence of any foreign bodies or concomitant bony injuries.
Ultrasound and MRI are highly accurate for identifying tendon lacerations, but are not typically needed when a proper physical examination is conducted.³
The strength of a tendon repair depends on the number of core sutures crossing the repair site; the thickness of suture (size); and the addition of an epitendinous edge suture.^2,17
Modern suture strength can exceed the strength of the tendon tissue. Failure then occurs as the suture pulls through the tendon’s collagen. Modern suture technique can decrease the risk of gap formation at the repair site and of suture pullout; however, in the end tendon healing is the deciding factor. ^2,17
Some modern suture techniques may be very strong, but in the end not very practical because they are exceedingly complicated, take too much tourniquet time to perform or are too bulky and interfere with tendon gliding.
Whether core suture knots are placed in the repair site where they may represent a foreign body in the healing zone or placed in the periphery of the tendon where the knots may interfere with gliding and predispose to adhesions is another unsolved debate.
A locking suture has a loop that passes around a group of tendon fibers and “locks” against these fibers as tension is applied. To achieve locking with a modified Kessler suture technique, the transverse suture component passes volar or superficial to the longitudinal component of the Kessler core suture. A grasping suture on the other hand pulls through the tendon fibers as tension is applied. When performing a grasping modified Kessler technique, the transverse arm of the suture passes deep (dorsal) to the longitudinal component of the Kessler core suture. Grasping suture can fail by pulling through the tendon fiber and locking suture can fail by cutting through the tendon fiber that the suture Is tied around.^2,17
When performing tendon repairs, avoid repetitive unnecessary grasping of the tendon during retrieval of the tendon ends and while suturing. Minor damage to the epitenon can increase the likelihood of adhesions. Each needle pass count should be made as accurately as possible because repetitive passes in the wrong location will weaken the tendon and increase the chance of cutting the previously placed sutures.

References

New and Cited Articles

Khor, WS, Langer, MF, Wong, R, et al. Improving Outcomes in Tendon Repair: A Critical Look at the Evidence for Flexor Tendon Repair and Rehabilitation. Plast Reconstr Surg 2016;138(6):1045e-1058e. PMID: 27879606
Tang JB, Amadio PC, Guimberteau JC, Chang J .Tendon Surgery of the Hand. Philadelphia: Elsevier; 2012.
Kamal, RN and Yao, J. Evidence-Based Medicine: Surgical Management of Flexor Tendon Lacerations. Plast Reconstr Surg 2017;140(1):130e-139e. PMID: 28654614
de Jong, JP, Nguyen, JT, Sonnema, AJ, et al. The incidence of acute traumatic tendon injuries in the hand and wrist: a 10-year population-based study. Clin Orthop Surg 2014;6(2):196-202. PMID: 24900902
Manninen, M, Karjalainen, T, Maatta, J, et al. Epidemiology of Flexor Tendon Injuries of the Hand in a Northern Finnish Population. Scand J Surg 2017;106(3):278-282. PMID: 27550244
Schoffl, V, Heid, A and Küpper, T. Tendon injuries of the hand. World J Orthop 2012;3(6):62-9. PMID: 22720265
Wong JK, Peck F. Improving results of flexor tendon repair and rehabilitation. Plast Reconstr Surg 2014;134(6):913e-25e. PMID: 25415114
Gibson PD, Sobol GL, Ahmed IH. Zone II Flexor Tendon Repairs in the United States: Trends in Current Management. J Hand Surg Am 2017;42(2):e99-e108. PMID: 27964900
Chauhan A, Palmer BA, Merrell GA. Flexor tendon repairs: techniques, eponyms, and evidence. J Hand Surg Am 2014;39(9):1846-53. PMID: 25154573
Pritsch T, Wong C, Sammer DM. Accuracy of Visual Estimates of Partial Flexor Tendon Lacerations. J Hand Surg Am 2015;40(12):2421-6. PMID: 26527592
Haimovici L, Papafragkou S, Lee W, et al. The impact of fiberwire, fiberloop, and locking suture configuration on flexor tendon repairs. Ann Plast Surg 2012;69(4):468-70. PMID: 22964669
Samora, JB and Klinefelter, RD. Flexor Tendon Reconstruction. J Am Acad Orthop Surg 2016;24(1):28-36. PMID: 26700631
Frueh FS, Kunz VS, Gravestock IJ, et al. Primary flexor tendon repair in zones 1 and 2: early passive mobilization versus controlled active motion. J Hand Surg Am 2014;39(7):1344-50. PMID: 24799144
Tang JB. Clinical outcomes associated with flexor tendon repair. Hand Clin 2005;21(2):199-210. PMID: 15882599
Lilly SI and Messer TM. Complications after treatment of flexor tendon injuries. J Am Acad Orthop Surg 2006;14(7):387-96. PMID: 16822886
Dy CJ, Hernandez-Soria A, Ma Y, et al. Complications after flexor tendon repair: a systematic review and meta-analysis. J Hand Surg Am 2012;37(3):543-551 e1. PMID: 22317947
Hotokezaka S, Manske PR. Differences between locking loops and grasping loops: effects on 2-strand core suture. J Hand Surg 1997; 22A:995-1003. PMID: 9471066

Reviews

Lineberry KD, Shue S, Chepla KJ. The Management of Partial Zone II Intrasynovial Flexor Tendon Lacerations: A Literature Review of Biomechanics, Clinical Outcomes, and Complications. Plast Reconstr Surg 2018;141(5):1165-1170.PMID: 29351182
Lutsky KF, Giang EL, Matzon JL. Flexor tendon injury, repair and rehabilitation. Orthop Clin North Am2015;46(1):67-76. PMID: 25435036

Classics

Morley GH. Flexor tendon injuries: a review of results. Br J Plast Surg1956;8(4):300-11. PMID: 13284237
Winter JS. Care of flexor tendon injuries. Proc R Soc Med1967;60(9):863-5. PMID: 6059063

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