The use of Vicryl™ in extensor tendon repairs

Conventionally, tendons are repaired with the strongest possible suture material, usually nonabsorbable in a variety of techniques using two or more strands between the tendon ends. In the initial phase of tendon healing, the repair is almost entirely dependent on the strength of the suture used and sound tendon suturing techniques. While this holds true for the strong flexor tendon system, we question the validity of this approach in the case of extensor tendons. Many of these are flat, and anecdotal evidence suggests that nonabsorbable sutures tend to promote a foreign-body reaction and cause increased tendon tethering. In this article, we seek to confirm that absorbable sutures such as Vicryl™ constitute a superior repair material for extensor tendons.     

Tendon injuries of the hand

Tendon injuries are the second most common injuries of the hand and therefore an important topic in trauma and orthopedic patients. Most injuries are open injuries to the flexor or extensor tendons, but less frequent injuries, e.g., damage to the functional system tendon sheath and pulley or dull avulsions, also need to be considered. After clinical examination, ultrasound and magnetic resonance imaging have proved to be important diagnostic tools. Tendon injuries mostly require surgical repair, dull avulsions of the distal phalanges extensor tendon can receive conservative therapy. Injuries of the flexor tendon sheath or single pulley injuries are treated conservatively and multiple pulley injuries receive surgical repair. In the postoperative course of flexor tendon injuries, the principle of early passive movement is important to trigger an "intrinsic" tendon healing to guarantee a good outcome. Many substances were evaluated to see if they improved tendon healing; however, little evidence was found. Nevertheless, hyaluronic acid may improve intrinsic tendon healing.     

Quadriceps and patellar tendon ruptures

Ruptures of the quadriceps as well as the patellar tendon occur in low frequency, but cause major functional deficits of the leg. These injuries usually require operative treatment. Acute quadriceps tendon ruptures are treated by suture repair, using heavy sutures guided through bone tunnels in the patella. Chronic defects and neglected cases require a local tendon transfer, either by a quadriceps tendon turn-down or by a V-Y-plasty of the quadriceps tendon. Ruptures of the patellar tendon are treated by suture of the tendon stumps plus an reinforcement procedure protecting the tendon and avoiding secondary patella alta. Patello-tibial fixation may be achieved by a cerclage technique using wire or an autologous tendon strip, alternatively a patello-tibial external fixator can be applied. In chronic and neglected cases, patellar tendon reconstruction is performed with autologous tendon grafts or with soft tissue allografts. The graft must be protected by a patello-tibial fixation for the first weeks.     

Primary flexor tendon repair in “no man's land”

Fifty-eight patients with 67 fingers with flexor tendon injuries in Bunnell's “no man's land” treated with primary repair were re-examined 14–84 months after surgery. Thirty-five fingers had repair of both tendons, and in thirty-two fingers the superficialis tendon was excised and only the profundus tendon was repaired. Postoperatively thirty-one fingers were treated by Kleinert's rubber band traction, and in thirty-six fingers a dorsal plaster of Paris was applied. The functional end-result was evaluated according to the method of Buck-Gramcko. Seventy-four per cent of fingers with suture of both tendons and 47 per cent of fingers with suture of only the prof undus tendon attained an excellent or good result. The fingers treated by Kleinert's rubber band traction achieved the most favourable functional result, but many inconstant factors had influence upon this evaluation. The number of re-operations were significantly higher after repair of only the profundus tendon.     

The influence of cross-sectional area on the tensile properties of flexor tendons

Clinicians have long noted substantial variation in the cross-sectional size of flexor tendons in the hand; however, data indicating that surgical repair techniques of lacerated flexor tendons should be altered according to size are unavailable. Our objectives were to evaluate the cross-sectional size differences among tendons within the same hand and to correlate tendon size with tensile mechanical properties after suture repair. Fifty human cadaver flexor digitorum profundus tendons were measured with digital calipers to determine radioulnar and volardorsal diameters. Twenty tendons were used to measure resistance to suture pull-through; tendons were transected at the A2 pulley, and a transverse double-stranded 4-0 Supramid suture (S. Jackson, Inc, Alexandria, VA) was passed through the radioulnar plane of the tendon 1 cm from the transection site. The remaining tendons were transected and repaired by using a modified Kessler repair with double-stranded 4-0 Supramid suture. Both tendon repairs and tendon-suture pull-through specimens were tested to failure in tension by using a material testing machine. Dorsovolar tendon height and tendon cross-sectional area varied significantly between digits, with an average difference of approximately 40% between the values of the smallest (fifth) and largest (third) fingers. Yield and ultimate force determined by pull-through tests of the simple transverse suture correlated positively with tendon radioulnar width. Tensile properties of tendons repaired with a double-stranded modified Kessler repair, however, did not depend significantly on tendon size. These results indicate that the strength of the commonly used Kessler suture technique is not dependent on tendon cross-sectional size within the clinically relevant range of tendons evaluated.     

Flexor tendon injuries in children

Flexor tendon injuries in adults differ from those in children. 38 children (22 male and 16 female) with a mean age of 6.7 years were treated for flexor tendon injuries by primary suture and controlled mobilization between 1985 and 1992. 53 flexor tendons were injured (average 1.5 digits per patient) and the injury most commonly affected the little finger (23 patients). 60% of injuries occurred in zone 2. Using Lister's criteria, 82% achieved excellent or good results. Repair of both FDS and FDP was better than repair of FDP alone, even in zone 2. There were three tendon ruptures(all classified as poor results) and one other poor result occurredin a zone injury with an associated ulnar nerve palsy. The outcome after flexor tendon repair in children is better than in adults in our hands because rapid healing of tendons occurs in children. No child has yet required tenolysis because in children adhesions are more pliable. Both flexor tendons should be repaired irrespective of the zone of injury. A functional hand can be expected after flexor tendon repair in children.     

Extensor tendon gap reconstruction: a review

Background: The extensor tendons of the hand are located in a superficial position on the dorsal aspect of the hand and are highly susceptible to injury. Laceration, crush and avulsion injuries are common extensor tendon injuries presenting for acute care. Such injuries that involve tendon loss or gaps in the extensor tendons require specialised attention and can be some of the most challenging to repair, as extensor tendons have less excursion than flexor tendons. Reconstructive techniques for such defects may differ according to the location of the defect, especially in Verdan’s extensor zones 1–5. Adequate repair of extensor tendon defects in zones 1–5 is especially important because (a) even a 1?mm tendon gap in those zones may cause 20° extension loss, and (b) shortening of the extensor tendon by as little as 1?mm may cause decreased finger flexion.

Review: This article reviews and discusses the literature on the various approaches and techniques for extensor tendon reconstruction, delineated by zone of injury (zones 1–8).

Conclsions: Awareness of the various techniques available to repair defects in each zone of injury is important so that surgeons can choose the technique most in alignment with the type of injury, the surgeon’s skills, and patient characteristics, and optimise the repair of such injuries.     

腱缝合后鞘内置入法在Ⅱ区屈肌腱修复中的临床应用

目的介绍用腱缝合后鞘内置入法，治疗Ⅱ区屈肌腱损伤的方法和疗效。方法按该法治疗屈肌腱损伤４６例７７指。伸直型１２例２６指：经原腱鞘伤口缝合肌腱，术毕将肌腱缝合部置于近侧健康鞘管内。屈曲型３４例５１指：在肌腱远断端以远约０．５ｃｍ处另作腱鞘切口，经此切口将损伤腱近端拉出进行缝合，术毕将腱缝合口置于远端切口和原伤口间的完整鞘管内。结果术后随访到３８例５９指，随访时间为２个月～３年，平均１年８个月。按ＴＡＭ评定法评定疗效，优级：３０指，良级：１７指，余为中差级；总优良率达到７９．７％。锐器切割伤４３指，疗效优良者４２指占９７．７％；合并腱鞘及周围组织损伤１６指，疗效优良者５指占３１．３％。结论该术式对单纯指屈肌腱损伤疗效满意，这可能和术时腱鞘损伤轻，肌腱缝合口被健康鞘管包绕后，有利于肌腱的内源性愈合并减少了外源性愈合的参与有关     

Early healing of flexor tendon insertion site injuries: Tunnel repair is mechanically and histologically inferior to surface repair in a canine model.

Orthopedic injuries often require surgical reattachment of tendon to bone. Tendon ends can be sutured to bone by direct apposition to the bone surface or by placement within a bone tunnel. Our objective was to compare early healing of a traditional surface versus a novel tunnel method for repair of the flexor digitorum profundus (FDP) tendon insertion site in a canine model. A total of 70 tendon-bone specimens were analyzed 0, 5, 10 or 21 days after injury and repair, using tensile and range of motion mechanical testing, histology and densitometry. Ultimate force (a measure of repair strength) did not differ between surface and tunnel repairs at day 0. Both repair types had reduced strength at 10 and 21 days compared to 0 days, indicative of deterioration of suture grasping strength (tendon softening). At 21 days, tendons repaired in a bone tunnel had 38% lower ultimate force compared to surface repairs (p = 0.017). Histological findings were comparable between repair groups at 5 and 10 days but differed at 21 days, when we saw evidence of maturation of the tendon-bone interface in the surface repairs compared to an immature fibrous interface with no evidence of tendon-bone integration in the tunnel repairs. After accounting for bone removed by the tunnel, no difference in bone mineral density or trabecular bone volume existed between surface and tunnel repairs. If the results of our animal study extend to healing of the human FDP insertion, they indicate that FDP tendons should be reattached to the distal phalanx by suture to the cortical surface rather than suture in a bone tunnel.     

Tendon and Ligament Healing and Current Approaches to Tendon and Ligament Regeneration

Ligament and tendon injuries are common problems in orthopedics. There is a need for treatments that can expedite nonoperative healing or improve the efficacy of surgical repair or reconstruction of ligaments and tendons. Successful biologically-based attempts at repair and reconstruction would require a thorough understanding of normal tendon and ligament healing. The inflammatory, proliferative, and remodeling phases, and the cells involved in tendon and ligament healing will be reviewed. Then, current research efforts focusing on biologically-based treatments of ligament and tendon injuries will be summarized, with a focus on stem cells endogenous to tendons and ligaments. Statement of clinical significance: This paper details mechanisms of ligament and tendon healing, as well as attempts to apply stem cells to ligament and tendon healing. Understanding of these topics could lead to more efficacious therapies to treat ligament and tendon injuries. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:7–12, 2020     

Prim?rversorgung komplizierter Beugesehnenverletzungen an der Hand

Complicated flexor tendon injuries are classified into lacerations, avulsions, ruptures, and defects. They are often a challenge for hand surgeons and frequently they present unsatisfactory functional results postoperatively. Lacerations and avulsions are usually treated by pull-out sutures and suture anchors. In ruptures, the causality should be sought. Tendon-linking, transposition and tenodesis/arthrodesis are the domain of rheumatoid arthritis. The primary transplantation of tendons is rarely indicated, ideally in non-contaminated flexor tendon defects in zones III-V with an uninjured surrounding soft tissue situation. Postoperative rehabilitation programs are very the same as in normal flexor tendon injuries.     

Treatment of partial lacerations in flexor tendons by trimming. A biomechanical in vitro study

BACKGROUND: Treatment of a partial laceration in zone 2 of a flexor tendon is controversial. The intact part of the tendon can usually sustain forces of normal unresisted motion, and repaired partially lacerated tendons can actually be weaker than unrepaired ones. However, complications such as triggering or entrapment have been reported in association with unrepaired tendons. The purpose of this study was to measure the biomechanical behavior following trimming of the tendon as an alternative to repair. METHODS: Thirty-six flexor digitorum profundus tendons were harvested from sixteen unpaired fresh-frozen cadaveric human hands and were randomly assigned to be subjected to either 50% or 75% partial laceration, which was either lateral or volar, and were then assigned to no repair, repair with a running suture, or trimming. Mean and maximum gliding resistances were measured as the flexor digitorum profundus glided through the bone-A2 pulley complex and the flexor digitorum superficialis. Values were normalized to those measured in the intact tendon. The tendons were then distracted to failure, and maximum load and stiffness were recorded. RESULTS: There was triggering or entrapment of eight unrepaired tendons; two cases were severe, and six were minor. When no severe trigger was obvious, the unrepaired tendons had the lowest tendency for gliding resistance, followed by the tendons treated with trimming and then by those treated with the running suture. Overall, the tendons with a volar laceration had higher mean and maximum gliding resistance than those with a lateral laceration (p < 0.05), those with a 75% partial laceration had higher mean gliding resistance than those with a 50% laceration (p < 0.05), and the tendons that were repaired with running suture had higher mean gliding resistance than those treated with trimming (p < 0.05). Tendon strength was not significantly different among the three types of treatment. CONCLUSIONS: From the perspective of gliding resistance after partial tendon laceration, no repair appears necessary unless triggering is a problem. If triggering occurs, then trimming of a partially lacerated tendon may be a reliable alternative to repair, at least in terms of gliding resistance and strength.     

The mechanical strength of various suture techniques.

The mechanical strengths of five techniques of tendon repair have been evaluated using human cadaver tendons. A modified Kessler repair with a peripheral circumferential suture and the method of Becker were found to require the greatest load to produce gapping, but the Becker and Savage repairs withstood the highest load before failure.     

Effects of direction of tendon lacerations on strength of tendon repairs

PURPOSE: We compared the tensile strength of different repair configurations on tendons with oblique and transverse lacerations. METHOD: Seventy-two fresh pig flexor tendons were divided randomly and repaired using the modified Kessler, the cruciate, or the 4-strand Massachusetts General Hospital (MGH) repair methods. The tendons were lacerated either transversely or obliquely. They were repaired with conventional and oblique suture repairs. The 2-mm gap formation force and ultimate strength were determined as biomechanical performance for each repair. RESULTS: The gap formation and ultimate strength of the tendons vary with orientations of tendon lacerations and suture methods. In the tendons repaired with the modified Kessler or the cruciate methods, the 2-mm gap formation and ultimate strength of obliquely cut tendons were significantly lower than those of transversely cut tendons. The obliquely placed modified Kessler or cruciate sutures significantly improved the repair strength in the tendons with an oblique laceration. In the tendons repaired with the MGH method, no statistical differences were found in the repair strength of obliquely and transversely lacerated tendons. CONCLUSIONS: The direction of tendon lacerations affects strength of certain repair configurations. The nonlocking modified Kessler or the cruciate tendon repairs are weakened considerably when the tendon laceration is oblique but their mechanical performance is strengthened by re-orienting the repair strands to lie parallel to the laceration. The cross-locked configuration of the MGH repair is not affected by the obliquity of the tendon laceration.     

Flexor tendon repair and rehabilitation in zone II open sheath technique versus closed sheath technique

A comparative prospective study of the surgical management of the tendon sheath after repair of flexor tendons in zone II is reported. The study included only patients with lacerations of both flexor tendons and no other associated injuries. A modified Kessler suture was used to repair the profundus tendon and the superficialis tendon was repaired with a horizontal mattress suture. In 48 fingers the flexor tendon sheath was left open and it was closed in the second group of 42 fingers. When it was impossible to close the tendon sheath, a vein patch was taken from the dorsal veins of the hand. Both groups of patients were treated with the same regimen of controlled motion rehabilitation and supervised by the same hand therapist. Results were evaluated by the Strickland formula for total active motion of the proximal and distal interphalangeal joints. There was no statistical difference between the results of open sheath versus closed sheath in these two groups of patients treated postoperatively with the same controlled motion rehabilitation program.     

Quadrizeps- und Patellasehnenrupturen

Ruptures of the quadriceps or patellar tendon are uncommon but extremely relevant injuries. Early diagnosis and surgical treatment with a stable suture construction are mandatory for a good postoperative clinical outcome. The standard methods of repair for quadriceps and patellar tendon injuries include the placement of suture loops through transpatellar tunnels. Reinforcement with either a wire cerclage or a PDS cord is used in patellar tendon repair. The PDS cord can also be applied as augmentation in quadriceps tendon repair. In secondary patellar tendon repair an autologous semitendinosus graft can be used. For chronic quadriceps tendon defects a V-shaped tendon flap with a distal footing is recommended. The different methods of repair should lead to early functional postoperative treatment. The clinical outcome after surgical treatment of patellar and quadriceps tendon ruptures is mainly good.     

Die primäre Naht der Fingerbeugesehnen

OBJECTIVE: Flexor tendon repair by direct suture, providing tendon function and mechanical properties and allowing postoperative active extension and flexion. INDICATIONS: Flexor tendon laceration in all zones, when primary healing and a good functional outcome can be expected. CONTRAINDICATIONS: Florid and chronic infection. Lack of skill, instruments, or manpower. Tension-free suture is not feasible. Severe soft-tissue problems. Mantero suture in case of coexistent artery injury. SURGICAL TECHNIQUE: Hand surgical incisions and approach to the tendon. Opening of the tendon sheath in the region of oblique pulley. A four-strand core suture consisting of two locked two-strand sutures and a circumferential epitendon cross-stitch suture are performed. Lacerations in zone I with a tendon stump shorter than 1 cm require a Mantero suture and avulsions require a pull-out suture technique. POSTOPERATIVE MANAGEMENT: Active flexion and active extension in a dorsal wrist cast. RESULTS: The clinical outcome studies after repair of zone II flexor tendon injuries using a multiple-strand suture technique describe 69-96% excellent and good results.     

Flexor tendon injuries: Repair & Rehabilitation

Flexor tendon injuries are common and occur mostly by penetrating trauma. Suspected flexor tendon injuries require a thorough clinical assessment and often are not isolated injuries. A detailed understanding of flexor tendon anatomy and spatial relationships is essential, especially when repairing multi-tendon injuries. Principles of flexor tendon repair include a strong suture construct, minimising gap formation between tendon ends, preserving tendon blood supply and providing a smooth repair interface. Moreover, adequate exposure of the zone of injury using full-thickness skin flaps and preservation of neurovascular and pulley structures is essential. In this article an overview of contemporary management strategies is presented. Today's hand surgeons and therapists can choose from a variety of treatment options when managing these important and potentially life-changing injuries.     

Locking repairs for obliquely cut tendons: Effects of suture purchase and directions of locking circles

PURPOSE: Oblique cuts in tendons weaken conventional repairs but locking sutures improve the repair strength of the tendon. In this study we assessed how suture purchase and direction (or type) of locking sutures affect the repair strength. METHODS: Ninety-three fresh pig flexor tendons were transected obliquely (45 degrees to the long axis of the tendon) and repaired with either a locking Kessler repair (with perpendicular or horizontal locking circles) or a locking cruciate method (with oblique locking or perpendicular locking circles). The suture purchase in the short side of the tendon stump with a perpendicular locking Kessler repair ranged from 0.3 to 1.2 cm. The gap formation and ultimate strength were measured to compare the biomechanical performance for each repair. RESULTS: The repair strength increased significantly as the suture purchase increased from 0.3 to 1.0 cm in oblique tendon lacerations, with a suture span of 1.0 cm being the strongest. The strength decreased significantly when the span was 1.2 cm. The repairs with horizontal locking sutures were significantly weaker than those with perpendicular locking sutures. The locking cruciate repair with the perpendicular locking circles had strength identical to that of the cruciate with oblique locking circles. CONCLUSIONS: Both suture purchase and the direction of locking circles affect the repair strength remarkably. For locking repairs the suture purchase of 1.0 cm in an obliquely cut tendon produced the highest strength; the repairs with a purchase less than 0.4 cm had significantly reduced strength. The strength of the repairs with locking circles perpendicular to the long axis of the tendon was significantly greater than that of the repairs with locking circles parallel to the long axis of the tendon.     

An experimental flexor tendon repair in zone II that allows immediate postoperative mobilization

An experimental method of approximating severed flexor tendons in zone II that allows immediate postoperative mobilization is described. The repair uses a nonabsorbable suture anchored into the severed tendon in zone III. This experimental repair was performed on one foot in each of 18 adult, white Leghorn chickens. The control side used the modified Kessler technique to repair the zone II laceration. The animals were prevented from weight-bearing activities but were allowed active motion of the foot for 5 to 6 weeks postoperatively. The results demonstrated a marked diminution in flexor tendon adhesions, with intrinsic tendon collagen formation serving to reconstitute tendon continuity on the experimental side. The breaking strengths of the two repair methods were equivalent. These results suggest that this method may allow primary repair of tendon injuries in zone II, with minimal formation of adhesions.