Verdan's Zone Research Articles

Minimally Invasive Suture Technique Pull-out to Repair the Acute Flexor Tendons in Zone II of the Hand.

Objective: To evaluate the safety and effectiveness of a modified pull-out suture technique in patients undergoing primary repair surgery for injuries to the flexor tendons of the fingers with Total Active Motion (TAM) as the primary outcome. Method: A total of 29 patients (38 fingers) were chosen from both sexes, aged between 18 and 65 years with clean acute tendon laceration occurring within 15 days, in the Verdan's zone II of flexor tendon in the hand, when only the deep flexor tendon was sutured, either associated or not with digital nerve injury. The patients were operated on using the proposed technique and evaluated at 3, 9 and 24-weeks PO. The primary outcome was the assessment of Total Active Movement (TAM) and 3 classifications were employed: Strickland, IFSSH and Buck-Gramcko. Results: We observed a total active motion (TAM) of 209.3 °at the end of 24 weeks; 83.0% of Good and Excellent results by the Modified Strickland Classification, 93% of Excellent results by the IFSSH Classification, and 97% of Good and Excellent results using the Buck-Gramcko Classification. There were no cases of rupture, but tendon adhesion was observed in 3 fingers. Conclusion: The present suture technique proved to be safe and effective with a low rate of complications, obtaining an excellent functional result in terms of total active mobility, according to the evaluations and classifications used.

Flexor Tendon Injuries in the Pediatric Population.

Flexor tendon injuries are rare in children, posing specific diagnostic and therapeutic challenges. This study aims to describe epidemiologic characteristics of flexor tendon injuries in children and evaluate the outcomes of surgical treatment. We conducted a retrospective study of patients with acute traumatic flexor tendon injuries treated between 2012 and 2019. We analyzed demographics, lesion mechanism, surgical technique, clinical results, complications, and secondary surgical procedures. Functional results were assessed through the Total Active Mobilization score. Twenty patients were included (n=34 tendons), with median follow-up of 7 months (range, 3-34 months) and median age at time of surgery of 13 years (range, 1-17 years). Male sex was predominant (n=16). The most prevalent injury mechanism was a cut (n=17), mostly affecting the 4th digit (n=10) and Verdan's zone II (n=13). Modified Kessler was the suture technique most commonly used (n=31), and polypropylene was the preferred suture material (n=19). All patients were immobilized with a splint for a median time of 4 weeks (range, 1-7 weeks). According to the Total Active Mobilization score, 15 patients reached a score greater than 75%, independently of age (P>.05). Stiffness was the main complication observed. Complications were identified in 37% of patients and were most common in those older than age 10 years (P>.05) and those with zone II lesions (P>.05). Four patients (20%) needed a second surgical intervention. Flexor tendon injuries in children are relatively uncommon and prevail in the male sex, similarly to the adult population. The principal complication observed was stiffness, which was more prevalent in children older than age 10 years, although without relevant functional implications, as surgical treatment enabled good or excellent outcomes in 75% of patients. [Orthopedics. 2023;46(2):82-85.].

Avance tendinoso no convencional para lesiones en las zonas I y II de Verdan. Nueva técnica quirúrgica

Objetivo: Presentar una nueva técnica quirúrgica y los resultados clínicos comparativos de pacientes con roturas de tenorrafia primaria o lesiones crónicas del flexor profundo en las zonas I y II de Verdan, tratados con avance tendinoso no convencional. Materiales y Métodos: Se incluyó a pacientes >18 años, con antecedente de lesiones en las zonas I y II de Verdan y un seguimiento mínimo de 36 meses. La serie estaba formada por 13 pacientes (edad promedio 29 años) que fueron divididos en dos grupos según el tipo de lesión (7 con roturas de tenorrafia primaria y 6 con lesiones crónicas del flexor profundo) y la técnica quirúrgica utilizada (alargamiento en Z más sutura término-terminal y sutura lateral del tendón alargado a un flexor vecino indemne en la zona V, respectivamente). Se empleó la Clasificación de Strickland para la evaluación. Resultados: El seguimiento promedio fue de 51 meses. El intervalo promedio entre la lesión y la cirugía fue de 11.7 semanas. Según la Clasificación de Strickland, 8 pacientes tuvieron resultados excelentes; 4, buenos y uno, pobre. El avance tendinoso promedio fue de 20,5 mm en ambos grupos. Conclusiones: El avance tendinoso no convencional para lesiones en las zonas I y II de Verdan, sea en roturas de tenorrafia primaria o lesiones crónicas del flexor profundo, resultó un tratamiento reproducible y eficaz. Palabras clave: Tendón flexor; alargamiento; zetaplastia.Nivel de Evidencia: III

Seasonal Trends in Traumatic Digit Amputations: Experience of a Level І and a Level ІІ Hospital in a Northeastern State.

Background: Traumatic digit amputations are common hand injuries in the United States. The primary aim of our study was to describe the relationship between season and mechanisms of amputation. Methods: The Emergency Department and Orthopaedic Surgery Billing Department databases of our level І institution in the Northeast were reviewed to identify patients with a traumatic digit amputation between January 2010 and December 2015. Inclusion criteria were defined as any patient presenting with a partial or complete amputation through Verdan zone I or II. All patient information was entered into a secure database, including date of injury, demographic information, digits amputated, mechanism of injury (crush, laceration, avulsion, bite, blast, saw, snow blower, or lawn mower), and Verdan zones of amputation. In addition to descriptive statistics, Fisher exact and χ2 tests were used to compare the incidence of these traumatic digit amputation mechanisms between seasons. Results: For this 6-year period, an average of 24 patients presented each season for treatment of a traumatic digit amputation. Of all seasons, spring had the highest proportion of lawn mower amputations (62.5%; P < .0001), summer had the highest proportion of blast amputations (75.0%; P = .011), and winter had the highest proportion of snow blower amputations (90.9%; P < .0001). All other traumatic digit amputation mechanisms had no significant seasonal variation in incidence (P > .30). Conclusions: Given that certain traumatic digit amputation mechanisms occur predictably during certain seasons, seasonal public education has the potential to prevent these debilitating injuries.

Ultrasonographic Evaluation of Zone II Partial Flexor Tendon Lacerations of the Fingers: A Cadaveric Study

Accurate assessment of zone II partial flexor tendon lacerations in the finger is clinically important. Surgical repair is recommended for lacerations of greater than 50% to 60%. Our goal was to evaluate ultrasonographic test characteristics and accuracy in identifying partial flexor tendon lacerations in a cadaveric model. From fresh-frozen above-elbow human cadaveric specimens, 32 flexor digitorum profundus tendons were randomly selected to remain intact or receive low- or high-grade lacerations involving 10% to 40% and 60% to 90% of the radioulnar width within Verdan Zone II, respectively. Static and dynamic ultrasonography using a linear array 14-MHz transducer was performed by a blinded musculoskeletal radiologist. Sensitivities, specificities, and other standard test performance metrics were calculated. Actual and measured percentages of tendon laceration were compared by the paired t test. After randomization, 24 tendons were lacerated (12 low- and 12 high-grade), whereas 8 remained intact. The sensitivity and specificity in detecting the presence versus absence of a partial laceration were 0.54 and 0.75, respectively, with positive and negative likelihood ratio values of 2.17 and 0.61. For low-grade lacerations, the sensitivity and specificity were 0.25 and 0.85, compared to 0.83 and 0.85 for high-grade lacerations. Ultrasonography underestimated the percentage of tendon involvement by a mean of 18.1% for the study population as a whole (95% confidence interval, 9.0% to 27.2%; P < .001) but accurately determined the extent for correctly diagnosed high-grade lacerations (-6.7%; 95% confidence interval, -18.7% to 5.2%; P = .22). Ultrasonography was useful in identifying and characterizing clinically relevant high-grade zone II partial flexor digitorum profundus lacerations in a cadaveric model.

The Pathomechanics and Management of Secondary Complications following Flexor Tendon Repair

Verdan classified injuries to the flexor tendons based on the anatomical location of transaction. Following repair, a number of management strategies have been developed to maximize the gliding amplitude of the tendons. Nonetheless, despite optimal management, complications arise. If these complications remain untreated, secondary pathomechanical changes will result in a kinematic chain disturbance. An appropriate treatment protocol includes attention to maintenance of integrity of the flexor tendon repair, while avoiding secondary complications due to reduced gliding amplitude. A biomechanical analysis of the dynamics of tendon gliding following repair in the various Verdan zones will be discussed in the context of common complications. This analysis may help in devising an appropriate therapeutic approach to avoid secondary complications following flexor tendon repair.

Results of primary extensor tendon repair in relation to the zone of injury and pre-operative outcome estimation

The outcome of primary extensor repair in hand surgery has been widely explored, but little systematic effort has been made to investigate the influence of the anatomical zone of tendon injury. Therefore, the aim of our study was to assess the outcome of primary extensor tendon repair with a special focus on the pre-operative state and Verdan's anatomical zones. Our hypothesis being tested was that the outcome after primary extensor repair depends on the complexity of trauma and the site of lesion. One hundred and seventy seven patients with 203 extensor tendon repairs were studied. After tendon repair and a 6-week protective immobilization, physiotherapy was carried out. A score proposed by Geldmacher and Schwarzbach was applied to estimate the outcome pre-operatively and to assess the results in a follow-up after a mean of 13 months. Correlations were tested between the anatomical zone of tendon injury, the pre-operative expectation and the results as considered both by the patient and the physician. In Verdan's zones 1, 2, 4 and 5, excellent or good results were obtained in the vast majority of patients. Due to a higher frequency of complex injuries with concomitant soft tissue and bony injuries, the outcome was significantly worse after tendon repair in zones 3 and 6, as expected after the pre-operative estimation. In addition, a strong correlation was found for all anatomical zones between the pre-operative estimation and the outcome as judged both by the physician and the patient. Recovery of finger function after primary extensor tendon repair depends on the complexity of trauma and the anatomical zone of tendon injury. Static splinting is an appropriate tool after primary extensor tendon repair in Verdan's zone 1, 2, 4 and 5, whereas injuries in zones 3 and 6 may demand for a different treatment regimen.

La plastie d'expansion en Oméga « Ω ». Une nouvelle technique d'expansion des poulies annulaires du tunnel digital fléchisseur

The authors report a new technique of pulley plasty of the flexor digital system. It is not an operative procedure to reconstruct a damaged pulley but an original way to expand the volume of an intact pulley in order to adapt its volume to the diameter of the repaired flexor tendon. The flexor tendons ruptures in Verdan zone II and particularly in Tang zones IIA and IIB are often accompanied by an osteofibrous tunnel injury. Initially, the tendon sheath closure was advised after tendons repair. This sheath recovery had to have an effect on tendons nutrition by establishing the synovial cavity continuity and particularly to protect the tendons from adhesions formation. The closure of the digital tube was rapidly shown to be unnecessary creating an obstacle to the tendons movements without any effect on tendons healing. In primary tendon management, the tendon repair is associated with an increase of the tendon diameter. An incongruence appears with the surrounding digital tube with gliding resistance complicating the tendon injury recovery. In secondary tendon injury management, the flexor digital tube is subject to healing and inflammatory process. This situation with the absence of the flexor tendon generates a retraction with a collapse of the digital tunnel over the injured area. This incongruence between the repaired flexor tendons and the narrowed digital tube required a release of the retracted zone to restore an adequate volume. The only way reported is the “Venting” of a part or the total length of the pulley. This procedure even if it resolves the tendon gliding resistance, is still unacceptable. Indeed it destroys an important anatomical structure of the flexor tendon dynamic system. The flexor pulley Omega plasty “Ω” consists in releasing the lateral palmar attachment of the pulley enhancing its internal volume and increasing the flexor tendon gliding area. The digital tube is composed by the succession of five annular and three cruciform pulleys. The cruciform pulleys are thin and flexible. They retract during the digital flexion assuring the continuity of the digital tube, while the annular pulleys are thicker and fill a biomechanical function. There are two types of annular pulleys: the joint pulleys as A1, A3 and A5; they are attached to the palmar plates of the MP, PIP and DIP joints respectively. During the digital movement, they retract approximately 50% of their length. The osseous pulleys as A2 and A4 are fixed over the lateral and palmar borders of the first and the second phalanx respectively. It is on these pulleys that the Omega plasty is practised. The operative procedure is simple. It consists on a periosteal dissection over the one lateral border of the phalanx. The liberation is undergone palmarly releasing the lateral attachment of the pulley. It respects the anatomical continuity of the pulley and its mechanical properties. Indeed, the continuity of the pulley is fully respected with the periosteal flap of the digital tube floor maintaining sufficient attachment to the pulley to resist to the flexor tendon forces. The level of the flexor tendon injury and the digit position during the initial trauma will determine the level of tendon resistance and where the pulley plasty must be made. If the flexor zone II injury occurred with the digit in an extension position, the tendon conflict appears with the A2 pulley, while it arises with the A4 pulley if the digit was in flexed position. The Omega plasty creates the ideal conditions for an optimal flexor tendon movement recovery. It is a simple and a reproducible procedure. It doesn't distort the mechanical properties of the pulley and the digital tube. We used this pulley Omega plasty fifteen times in twelve patients. In 60% of the cases, the injury concerned the dominant hand, and in 67% of the cases, it was a work accident. In eight of our cases, the omega plasty was done in emergency at the same time of flexor tendon repair, while in the other seven cases, the pulley Omega plasty accompanied the late flexor tendon repair forgotten during the initial trauma management. In ten cases, the plasty concerned the A4 annular pulleys, while in the other five cases, it concerns the A2 annular pulleys. Four cases necessitate a secondary tenolysis three months after the tendon repair. Two patients moved out and cannot be included in our results. On the thirteen-remainder cases, nine retrieved a full digital flexion particularly those who underwent digital tenolysis, while the other four cases retrieved a satisfying digital function in spite of the partial DIP flexion. In our hand, the pulley Omega plasty “Ω” becomes almost a systematic procedure in conjunction with the flexor tendon repair. It offers the ideal conditions for a tendon healing and a physiological flexor tendons motion recovery.

Immediate active mobilisation after flexor tendon repairs in Verdan's zones I and II: A prospective study of 20 cases

The authors report their experience with early active mobilisation after repair of complete sections of the flexor tendons within the digital tendon sheath. This is a prospective study carried out over 2 years and represents 20 repairs. The tendons were repaired using a double-loop looking suture of Tsuge (with PDS 4/0) associated with a peritendinous overrun using Prolene 6/0 via a volar Bruner-type incision. Post-operatively, a plaster splint holding the wrist in 30 degrees of flexion, the MP joints in 90 degrees of flexion and allowing complete active flexion of the finger protected the suture site. As soon as the dressings could be reduced (the 5th day post-operatively), the patient was encouraged to actively and synchronously flex all the fingers together as many times as possible during the day. After removal of the plaster splint at one month, the patients were entrusted to a physiotherapist with a view to regain full extension of the wrist and the fingers. We did not note a single case of breakdown of the repair. The mean active mobility (TAM according to Strickland) of the repairs in zone I was of the order of 70% while that for repairs in zone II was 85%. Immediate active mobilisation was not found to compromise, in any way, the results of associated digital nerve repairs. Despite the modest results, this simple-to-understand protocol is directed at present for injuries with a poor initial prognosis (contused and lacerated tendons, associated fractures, and non-motivated patients). Improvement in the quality of suture material should, in future, extend the indications for immediate active mobilisation to all fresh sutures of the flexor tendons.

Biomechanical analysis of four-strand extensor tendon repair techniques

Experience with flexor tendon repairs has suggested the superiority of the augmented Becker (MGH) technique for strength, toughness, and gap resistance. In an effort to apply these findings to the extensor tendons, 3 four-strand extensor tendon repair techniques were biomechanically tested in fresh human cadaver limbs: modified Bunnell, modified Krackow-Thomas, and MGH. Repairs were performed in Verdan's zone VI. Repaired tendons were distracted at constant speed until rupture. Tendon load and tendon distraction were continuously monitored. Benchmark values for load were measured as fingers were pulled from full metacarpophalangeal (MP) joint flexion to full extension, to 1-mm gap formation at the tenorrhaphy, and to complete rupture of the repair. The MGH repair proved significantly more resistant to gap formation (stronger and tougher) than the Bunnell and Krackow-Thomas repairs (p < .02). No differences were seen between groups in repair performance at MP joint extension and at complete rupture. This study suggests that the MGH technique has superior gap resistance to the other four-strand methods tested for extensor tendon repair in Verdan's zone VI. The MGH repair is recommended for extensor tendon repairs in zone VI when early postoperative motion regimens are considered.

Replantation and revascularization of the digits in a community microsurgical practice.

One-hundred and twenty-seven digits in Verdan zones I and II, and 24 thumbs in 106 patients were reviewed from 1979 to 1995. Patients were all followed for a minimum of 5 months to assess early results and complications, and to determine if a short course (minimum 3 days) of dextran 40 anticoagulation adversely affected digit survival. The total survival rate was 88 percent. Digits with only a single artery and vein repaired had a significantly higher rate of failure (p > .05). Index and small fingers also showed a trend toward lower survival. Vein grafts were used in 22 percent of cases. No vascular problems were noted after 5 days. Variables not affecting survival were: presence of a joint fusion, type of fixation, level of injury, number of digits, mechanism of injury, and use of vein grafts. The average hospital stay for the group was 6.5 days (+/-SD 3.3). No complications were seen with dextran use. A total of 51 complications were seen overall and the non-union rate was 10 percent. Community-based replantation and revascularization can be performed with early results equivalent to prior published studies. Complications are to be expected and demand expeditious treatment. Functional recovery of severed digits remains the benchmark for success in these injuries, however, lost digits never work.

L'histoire de la chirurgie des tendons fléchisseurs

Flexor tendon injuries were already treated in antiquity by Hippocrates, Galien and Avicenne. Since the Renaissance, other surgeons have attempted to repair flexor tendon injuries, but without success due to problems related to unsuitable materials and ignorance of the basic rules of asepsis and the absence of antiseptics until the second half of the 19th century. The first successful flexor tendon grafts in man were performed by K. Biesalski in 1910, E. Lexer in 1912 and L. Mayer in 1916. These three authors published their series of grafts and described in detail the anatomical, physiological and technical principles to be respected. St. Bunnell, in 1918, developed various pull-out direct suture procedures, but faced with the problems of adhesions, he abandoned this technique and proposed not to repair flexors in the digital tunnels but to graft them. He defined the famous zone which he called No man's land, which subsequently became Claude Verdan's zone II, in 1959. In 1960, C. Verdan published his first series of sutures maintained by 2 pins in zone II with comparable results to those obtained after grafting. In 1967, H. Kleinert, with his mobile suture, became the leader of direct tendon repair in zone II. 2-stage grafts were introduced in 1965 under the impetus of J. Hunter, who revised and popularized the studies conducted by A. Bassett and R.E. Caroll in 1950.

Wrist position and extensor tendon amplitude following repair

After primary repair of severed extensor tendons, various methods are used to limit tendon adhesions and avoid rupture. Early passive digital motion with wrist extension (a “reverse Kleinert” protocol) has been advocated. However, there are no data to support an optimum wrist position or to indicate how much finger motion may safely be permitted. In this study we used eight fresh cadaver limbs to measure extensor tendon gliding in Verdan's zones 3 to 8 when active grip and passive extension were simulated at different wrist positions. We found that if the wrist is extended more than 21 degrees, the extensor tendon glides with little or no tension in zones 5 and 6 throughout full simulated grip to full passive extension, permitting “passive motion” exercises to minimize tendon adhesions without risking rupture. in addition, we found that up to 6.4 mm of tendon can be debrided safely and full grip can still be permitted post-operatively if the wrist is splinted at 45 degrees extension.

Direct Tendon Suture of Flexor Tendon Injuries in the Hand

During the period from 1979 to 1982, we have performed 33 operations (involving 30 cases) of the direct tendon suture for the treatment of flexor tendon lacerations in the hand. There were 19 males and 11 females. The average age of patients was twenty-one years old. According to the Verdan's Zone Classification, Zone 1 was seen in 7 digits Zone 2 in 20 digits, Zone 4 in 1 didit and Zone 5 in 5 digits. The operative method was as follows. Skin incision was made using Bruner's zigzag incision and tendon suture was applied by Tsuge's intratendinous tendon suture method in the majority of the cases. Postoperative care was early mobilization of Kleinert's method in 13 cases and plaster fixation for 3 weeks in 20 digits.The evaluation was made according to Boyes- White's method and the results were classified as follows. Eighteen digits were excellent, eight good, three fair and four poor. Of all cases, 78.8% showed excellent or good results. According to the zone, 70% were excellent or good for Zone 2, 92.3% were excellent or good for Zone 1, 4 and 5. We studied the relationship of the results to age, time of operation, causes of injury, operative method (FDS suture or not) and postoperive treatment in those cases.