Core Suture Technique Research Articles

The effect of the number of strands and knot throws of core suture techniques on the mechanical properties of the repaired flexor tendon.

Flexor tendon injury is a common hand trauma that requires surgical repair. The objective was to compare the repaired strength and gliding resistance with a varied number of repair strands and of square knots using a two-strand-overhand locking (TSOL) knot. First, isolated suture loops with different number of suture strands and number of closing knots were compared in mechanical strength and failure mode. Then, 90 flexor digitorum profundus (FDP) tendons from turkey digits were used for the tendon repair experiment. Both phases followed a similar 3 × 3 matrix comparing the knot type including TSOL+1SK (square knot), TSOL+2SK, and TSOL+3 SK and repair techniques including two-, four-, and six-strand repairs techniques respectively. The repaired tendons were tested for tendon resistance against pulley (friction), maximum force, force at 2 mm displacement, stiffness, and failure mode. Increasing the number of strands and closing square knots increases the tensile strength and stiffness of flexor tendon repairs and isolated suture loops without a significant effect on tendon friction. An increase in the number of square knots have shown increased strength only in Pennington repair, which correlated with the increased number of knot unraveling, a weak knot failure model. Our data demonstrated that increasing the number of strands is effective for improving the overall strength of tendon repair. When a two-strand repair is chosen, increasing knot number can improve repair strength. However, the number of knots appears not affecting repair strength in six-strand repair technique.

Comparison of 4 Different 4-Strand Core Suturing Techniques for Flexor Tendon Laceration: An Ex Vivo Biomechanical Study.

Forces applied to the repaired flexor tendon should not exceed its yield force during early postoperative rehabilitation to prevent gapping and rupture. We aimed to biomechanically compare the tensile strengths and the 2-mm gapping of 4 different 4-strand core suturing techniques for flexor tendon repair. Fifty-six goat deep digital flexor tendons were repaired with the 4-strand double-modified Kessler, the 4-strand augmented Becker, the 4-strand Savage, and the 4-strand modified Tang techniques. All tendons were repaired with 4-0 polyester for core suture and 5-0 polyester for continuous epitendinous running suture. The specimens were subjected to static linear tensile testing by applying a single linear load-to-failure pull. After the linear load testing, the yield load, the ultimate strength of the repaired tendons, and the force exerted to yield a 2-mm gap were measured. All peripheral sutures ruptured near the yield point. All core suture techniques were similar regarding the yield force. The augmented Becker 4-strand technique had the greatest ultimate strength (98.7 [82-125.3] N). The modified double Kessler technique was the weakest in resisting a 2-mm gap formation. The 4-strand modified Tang repair had the shortest (11.3 [7-15] minutes), while the 4-strand augmented Becker had the longest operative time (29 [23-33] minutes). All 4 techniques demonstrated similar yield force, with differences in operative time, ultimate strength, and resistance to gapping. Future clinical studies can further elucidate their appropriateness for early active motion protocols.

Rupture Rate, Functional Outcome and Patient Satisfaction after Primary Flexor Tendon Repair with the Modified 4-Strand Core Suture Technique by Tsuge and Using the Arthrex FiberLoop® with Early Motion Rehabilitation.

Purpose:Our hypothesis was that the rupture rate after primary flexor tendon repair in the modified 4-strand core suture technique using the FiberLoop® (Arthrex, Munich, Germany) is lower than in other suture materials and functional outcome and patient satisfaction are superior compared to the current literature. Patients and methods: A 2-stage retrospective, randomized follow-up study of 143 patients treated with the Arthrex FiberLoop® after flexor tendon injury in zones 2 or 3 from May 2013 to May 2017 was performed. In the 1st stage, the rupture rate of all patients was assessed after a follow-up of at least one year by interview to exclude revision surgery. In the 2nd stage, 20% of the patients could be randomly clinically examined. Functional parameters, such as finger and wrist range of motion measured by goniometer, grip strength measured by Jamar dynamometer (Saehan, South Korea), patient satisfaction measured by school grades (1–6), pain levels measured by visual rating scales (0–10) and functional outcome according to the DASH-score were assessed. The Buck-Gramcko and Strickland scores were calculated. The length of sick leave was recorded. Results: A rupture rate of 2.1% was recorded. 29 patients (20%) were followed up at a mean of 34 ± 7.5 months postoperatively. 10.3% of these patients had an incomplete fingertip palm distance. The mean postoperative grip strength was 24 ± 3.1 kg. 93% of the patients were very satisfied with the treatment. No patient complained of pain postoperatively. The mean postoperative DASH score was 6.7 ± 2.8 points. The mean Buck-Gramcko score was 14 ± 0.2 points. 93% of the patients had excellent and 7% good results according to the Strickland score. 67% of patients had a work accident and returned to work at a mean of 4 ± 0.2 months postoperatively. 31% of patients suffered a non-occupational injury and returned to work at a mean of 3 ± 0.4 months postoperatively. Conclusions: Primary flexor tendon repair in the modified 4-strand core suture technique using the Arthrex FiberLoop® has proven to be a viable treatment option in our series. The rupture rate was lower than in other suture materials. It leads to acceptable pain relief, grip strength and functional outcome. Level of Evidence: IV; therapeutic.

Outcomes and rupture rate of the “Adelaide” four-strand repair for zone 2 flexor tendon injuries over a 10-year period

Multi-strand core suture techniques combined with early active mobilization regimens have demonstrated improved functional outcomes in zone II flexor tendon injuries. This study evaluated the integrity of the “Adelaide” four-strand repair and assessed its outcome on function. All zone II flexor tendon repairs were identified from a prospectively collected database from 2002 to 2012. Patient demographics, number and type fingers injured, neurological deficits, length to surgery, and rupture rates were recorded. Strickland and Modified Strickland measurements assessed the functional outcome. Follow-up was for 12 weeks post-operatively. A total of 167 patients and 197 fingers were identified, of which 111 and 125 respectively had complete data for analysis. Patient demographics included 93 males and 18 females with a mean age of 28.6 years (15–68). The most common finger injured was index 41/125 (35%), 105/111 (95%) had surgery within 3 days, 69/125 (55%) had an associated digital nerve injury, and 44/111 (40%) were smokers. Strickland and Modified Strickland calculations demonstrated 92/125 (74%) patients had a good/excellent result, 25/125 (20%) fair, and 8/125 (6%) had a poor result. Rupture rate was 5/125 (4%). The “Adelaide” repair combined with early active mobilization achieves a good functional outcome with low rupture rates. Level of evidence: Level III; therapeutic study

Primary treatment of flexor tendon injuries

The treatment of flexor tendon injuries is still challenging, especially in the region of the narrow annular ligaments and tendon sheaths of the 3‑segment fingers and the thumb (zone2). In the course of time, the primary suture of the flexor tendons has prevailed over traditional recommendations for asecondary tendon replacement after healing of the wound. Improvements regarding suture techniques and materials and, above all the follow-up treatment, have been crucial for better results and remarkable changes in flexor tendon surgery. The suture techniques are determined by the location of the injury but the experience and preferences of the surgeon are also important. Although no technique was found to be optimal, published research and clinical experiences provide important indications for the presumption of successful treatment. To achieve this an early functionally active protocol should be implemented. The tendon suture should enable this by having ahigh primary strength and therefore at least a4-strand core suture technique with a ring suture should be given preference. Further important prerequisites for success are the undisturbed gliding of the repaired tendon in its "bed" paying special attention to the annular ligaments and preservation of the blood supply to the tendons.

Evaluation and characterization of waterborne biodegradable polyurethane films for the prevention of tendon postoperative adhesion.

BackgroundTendon adhesion is a serious problem and it affects tendon gliding and joint motion. Although recent studies have yielded promising results in developing anti-adhesion materials, there are still many problems. Polycaprolactone (PCL)-based polyurethane (PU) has good mechanical properties and biocompatibility, and it has a potential in anti-adhesion applications.Materials and methodsIn this study, a series of waterborne biodegradable polyurethane (WBPU) films with different ratios of ionic groups were synthesized. In order to select an effective anti-adhesion film, the WBPU films were cast and characterized for physicochemical properties and biocompatibility.ResultsAll WBPU films were non-cytotoxic in the cell viability test and had suitable physicochemical and mechanical properties based on the measurement of zeta potential, water contact angle, mechanical properties, water absorption, thickness change, and gelatin test. To evaluate the anti-adhesion effect, severely injured tendons of rabbits were sutured with the modified Kessler core suture technique and WBPU films were then wrapped around the tendon. Implantation in rabbits showed that the WBPU film had better anti-adhesion effect than PCL films and the untreated control, and demonstrated no significant difference in the anti-adhesion performance from the commercial product Seprafilm based on gross evaluation, histological analysis, and biomechanical assessment.ConclusionCompared to Seprafilm and PCL applied in the tendon anti-adhesion, WBPU had better mechanical properties, low inflammatory reaction, and a proper degradation interval.

Results of 4-strand modified Kessler core suture and epitendinous interlocking suture followed by modified Kleinert protocol for flexor tendon repairs in Zone 2

ObjectiveThere has been no consensus in literature for the ideal flexor tendon repair technique. The results of zone 2 flexor tendon lacerations repaired primarily by 4 strand Modified Kessler core suture and epitendinous interlocking suture technique followed by Modified Kleinert protocol were investigated. Methods128 fingers of 89 patients who had flexor tendon laceration in zone 2 built the working group. Functional outcomes were evaluated using the Strickland formula. A statistical analysis was made between Strickland scores and some parameters such as age, gender, follow-up time, co-existing injury existence, repair time, single or multiple finger injury, tendon rupture and the effect of FDS injury and repair. ResultsExcellent, good, fair, poor results were obtained from 71 (55.5%), 46 (35.9%), 8 (6.3%), 3 (2.3%) fingers, respectively. Time of the repair has a significant effect on the strickland scores. Surgery performed within the first 24 hours following the injury gave better results. 3 fingers (2.3%) had tendon ruptures. Existence of ruptures affected the results significantly. Co-existing injuries were found that they did not have any effect on the results. In the fingers in which both FDP and FDS tendons were lacerated, no significant relationship was found between only FDP repair, both FDP and FDS repair and single FDS slip repair. Additionally no significant relationships between follow-up time, gender, single or multiple finger injury and Strickland scores were observed. 13 fingers (10.1%) had PIP joint contracture above 20°. ConclusionThe low rupture rate (2.3%) and 91.4% ‘good’ and ‘excellent’ scoring rates in our series support the idea that modified Kessler 4-strand core suture and epitendinous interlocking suture repair combined with modified Kleinert protocol gives satisfactory results. Repair time is one of the most important factors affecting the functional results and surgery should not be delayed if there is an experienced surgeon available. Level of evidenceLevel IV, therapeutic study.

Comparison of Roll Stitch Technique and Core Suture Technique for Extensor Tendon Repair at the Metacarpophalangeal Joint level.

Background:Proper suturing technique is needed to ensure good outcome in extensor tendon surgery. Different techniques have been reported for the repair of extensor tendon injuries at the level of the metacarpophalangeal joint (MCPJ). These reports were in vitro studies on cadaver models. Repair techniques must be clinically tested, to determine results.Objectives:The purpose of this in vivo study was to compare results of extensor tendon repair, using roll stitch and core suture techniques.Patients and Methods:Forty two fingers, in 38 patients (aged 15- 45 years), with simple complete extensor tendon injuries in the MCPJ area, were identified and operated by a single surgeon. The patients were divided into two groups, according to the technique used for tendon repair. The first group consisted of 21 digits, in 19 patients, who were repaired with roll stitch technique, while the second group consisted of 21 digits, in 19 patients, who were repaired with core suture technique. The same splint and rehabilitation regimen (early passive range of motion) were given to all patients. The splints were removed at 6 weeks after surgery and range of motion of the operated fingers was measured and compared to uninjured hands, after 12 weeks.Results:Five patients were lost to follow up or excluded from the study. There was no rupture of the repaired tendons in the groups. There was no statistically significant difference in mean MCPJ flexion, proximal interphalangeal joint (PIPJ) flexion, distal interphalangeal joint (DIPJ) flexion and total range of motion of the fingers, between the two groups. However, extension lag was significantly more common in the second group (11 of 19 digits) compared the first group (four of 17 digits).Conclusions:Roll stitch technique had superior outcome compared to the modified Kessler technique, when performed in the MCPJ area. Level of evidence: Therapeutic (Level III)

Early Passive Movement in flexor tendon injuries of the hand.

Flexor tendon injuries are underestimated considering their anatomical function in the hand. According to the publications of Kleinert, Verdan and Kessler, primary suturing of the flexor tendon combined with immediate postoperative physiotherapy in terms of "Early Passive Movement" became the standard form of therapy following acute flexor tendon injuries of the hand. In a study between 2007 and 2009, a total of 115 flexor tendon injuries were analysed retrospectively. All patients were treated using a two-strand repair technique according to Zechner. They received physiotherapy from the first postoperative day according to the Viennese flexor tendon rehabilitation protocol. For statistical purposes, the factors: age, gender, range of motion (ROM), follow up interval, affected flexor tendon and zone were analysed. The time between injury and surgery was also determined, classified into groups and included in the study. On the basis of the range of motion AROM, the Buck-Gramcko and modified Strickland Score was calculated. The mean follow-up interval was 7 months. Using the Buck-Gramcko and Strickland Score an "excellent" overall result was achieved. Complications occurred in 3.5 %, one secondary rupture (0.9 %), two tendon adhaesions requiring tenolysis (1.7 %) and one case of infection (0.9 %). The time interval between injury and operation, gender, affected zone, flexor tendon and affected finger nerve had no influence on the Buck-Gramcko and Strickland Score. Using Zechner's core suture technique as the primary treatment, combined with immediate postoperative physiotherapy in terms of "Early Passive Movement" according to the Viennese flexor tendon rehabilitation programme, an excellent clinical outcome and low complication rate was acchieved. IV: case series.

A new modified Tsuge suture for flexor tendon repairs: the biomechanical analysis and clinical application.

PurposeThis study is to develop a new suturing technique for flexor tendon repair by modifying the extant Tsuge repair techniques and to use biomechanical analysis to compare the new method with four established repair techniques and evaluate its clinical efficacy in the repair of 47 flexor tendons in 22 patients.MethodsThe biomechanical analysis relied on 50 flexor digitorum profundus tendons harvested from fresh cadavers. The tendons were randomly divided into five groups, transected, and repaired by use of a 1. double-loop suture, 2. double modified locking Kessler, 3. four-strand Savage, 4. modified six-strand Savage, and 5. the new technique. The tensile force and breaking force of all repaired tendons were measured by static loading trials. For clinical application, 22 patients with acute flexor tendon injuries were treated with the new modified Tsuge suture and follow-up for more than 12 months.ResultsWhile differences in the tensile force and breaking force in the modified Tsuge sutures and modified six-strand Savage sutures were not statistically significant, static loading trials showed the tensile force, in the form of a 2-mm gap formation, and the breaking force of the new modified Tsuge sutures were, statistically, both higher than the ones characteristic of double-loop sutures, double modified locking Kessler, and four-strand Savage sutures. After 12 months, restored functions were observed in all the patients during the postoperative 12 months. Total active motion (TAM) score demonstrated that more than 90% fingers were estimated as excellent or good.ConclusionThe new modified Tsuge sutures described here have evident higher tensile and breaking forces compared to other four-strand core suture techniques, suggesting, in turn, that this new technique is a good alternative for flexor tendon repairs in clinical applications.

Clinical use of a combined grasping and locking core suture technique for flexor tendon repair in zone II

Previous authors have used either a grasping or a locking technique for flexor tendon repair in zone II. A combined (grasping and locking) 10-strand repair was used by the author in 22 adults (n = 28 fingers) with lacerations of both flexor tendons in zone II. The combined repair is known to be strong (mean tensile strength of 164 N), and the technique was used in selected cases who were thought to be at higher risk of rupture either because of excessive digital oedema (in early tendon repairs) or because of tendon retraction (in late primary tendon repairs). The 10-strand repair was bulky and, hence, only the profundus tendon was repaired; and “venting” of the pulley system was done proximal to the repair site as recommended by other authors. Supervised early active mobilisation was done immediately after the operation. At final follow-up, the outcome was calculated using the original Strickland-Glogovac grading system. There were no ruptures and the final outcome was considered excellent in 19 patients (n = 25 fingers), good in two patients (n = 2 fingers), and fair in the remaining patient (n = 1 finger). It was concluded that the bulky 10-strand repair may be used for zone II finger flexor tendon lacerations as long as a profundus–(?) only repair and “venting” of the pulley system are performed.

Zone 2 flexor tendon injuries: Venturing into the no man’s land

Flexor tendon injuries are seen commonly yet the management protocols are still widely debated. The advances in suture techniques, better understanding of the tendon morphology and its biomechanics have resulted in better outcomes. There has been a trend toward the active mobilization protocols with development of multistrand core suture techniques. Zone 2 injuries remain an enigma for the hand surgeons even today but the outcome results have definitely improved. Biomolecular modulation of tendon repair and tissue engineering are now the upcoming fields for future research. This review article focuses on the current concepts in the management of flexor tendon injuries in zone 2.

Clinical Outcomes of Zone II Flexor Tendon Repair Depending on Mechanism of Injury

To determine whether mechanism of injury affects outcomes of Zone II flexor tendon repairs. We retrospectively analyzed patients who underwent Zone II flexor tendon repair between 2001 and 2010 with a minimum of 12-month follow-up. Exclusion criteria included fingers with fracture, pulley reconstruction, or flexor tendon bowstringing. The saw group injuries were from saws or from tearing mechanisms; the sharp group had clean transection injuries from knives or glass. At final evaluation, primary outcomes were total passive motion (TPM) and total active motion (TAM) at the proximal interphalangeal and distal interphalangeal joints. Secondary comparisons included strength, Disabilities of the Shoulder, Arm, and Hand (DASH) score, percentage of postoperative tendon rupture, and percentage of patients requiring secondary surgery. The saw group had 13 patients with 17 fingers studied. The sharp group had 21 patients with 24 fingers studied. All patients had primary flexor digitorum profundus repairs in Zone II. Operative records review confirmed for all but 1 patient that flexor digitorum profundus injuries were repaired with a minimum of a 4-strand core suture technique. In the saw group, 9 of 14 fingers with a 50% or greater laceration of flexor digitorum superficialis were repaired; in the sharp group, 15 of 18 such flexor digitorum superficialis injuries were repaired. Average follow-up was 4 years (range, 1-9 y). The saw group had significantly less TAM and TPM compared with the sharp group. There was no significant difference in DASH scores, strength measurements, or tendon rupture rates. The rate of secondary surgery was significantly higher in the saw group. Tearing types of injury, such as those caused by saws, led to poorer outcomes for Zone II flexor tendon injuries compared with sharp injuries at an average follow-up of 4 years. Our results can be useful when discussing expected outcomes. Mechanism of injury in Zone II flexor tendon lacerations may eventually help define optimal treatment.

Complications After Flexor Tendon Repair: A Systematic Review and Meta-Analysis

Although outcomes after flexor tendon repair have reportedly improved with modern treatment, complications are common. The purpose of this study was to determine the incidence of these complications and the potential contributory factors within the published literature. We performed a systematic review of the available literature to identify publications in which patients with flexor tendon ruptures were surgically treated. We extracted demographics, zone of injury, core suture technique (only modified Kessler or a combination of techniques), use of epitendinous suture, and date of publication (before or after January 1, 2000). We excluded articles if they did not report information on reoperation, rupture, or adhesions. We used unadjusted pooled meta-analysis to report the incidence of complications, and meta-regression to describe the potential contributory factors for each complication while controlling for age, gender, and zone of injury. Unadjusted meta-analysis revealed rates of re-operation of 6%, rupture of 4%, and adhesions of 4%. Meta-regression analysis of 29 studies showed that core suture technique or use of an epitendinous suture does not influence rupture. However, the presence of an epitendinous suture decreases re-operation by 84%. Adhesion development is 57% lower when the modified Kessler technique is used. The incidence of complications did not vary with publication date. The published literature supports use of the modified Kessler repair technique with an epitendinous suture to minimize complications. Although complication rates are low, our data suggest that there has been no definitive improvement in reported complications before and after 2000.

An Ex Vivo Biomechanical Study Comparing Strength Characteristics of a New Technique with the Three‐Loop Pulley for Equine Tenorrhaphy

To test single cycle to failure tensile strength characteristics of 6 suture material-pattern combinations in equine superficial digital flexor (SDF) tenorrhaphy, specifically to compare a 10-strand modification of the Savage core suture technique with the 3-loop pulley technique. Ex vivo mechanical experiment comparing 3 different suture patterns with 2 different materials. Forelimb and hindlimb SDF tendons (n=48) harvested from adult Thoroughbred and Standardbred horses of mixed age and gender. Six suture material-pattern combinations were evaluated: (1) 10-strand Savage, size 2 polydioxanone (PDS); (2) 10-strand Savage, size 2 polyglactin 910 (PG910); (3) 10-strand Savage, size 2 PDS with Lin-locking epitenon suture, size 2-0 PDS; (4) 10-strand Savage size 2 PG910 with Lin-locking epitenon suture, size 2-0 PDS; (5) 3-loop pulley, size 2 PDS; and (6) 3-loop pulley, size 2 PG910. Maximum load at failure (N), gap at failure (mm), and mode of failure (suture breakage or pull through) were evaluated for each of the 6 suture material-pattern combinations and underwent statistical analysis to determine significance of differences and interactions of the measured data. The 10-strand Savage technique failed at a mean load of 872 (804-939, 95% CI). The 10-strand Savage with Lin-locking failed at a significantly greater mean load of 998 (930-1065, 95% CI). The 3-loop pulley pattern failed with a mean load of 337 (270-405, 95% CI). There were significant interactions between the technique and suture material used. The 10-strand Savage technique for repair of transected cadaver SDF tendons has superior strength characteristics with or without the epitenon suture when compared to the 3-loop pulley. Suture material and pattern interactions were observed with PG 910 conferring higher strength for the 10-strand Savage whereas PDS did so for the 3-loop pulley.

A biomechanical study of flexor tendon repair in zone II: Comparing a combined grasping and locking core suture technique to its grasping and locking components

All previous experimental and clinical repairs of flexor tendons in zone II have used either a grasping or a locking technique. In this article, a combined (grasping and locking) repair was compared biomechanically to its grasping and locking components. Using fresh flexor profundus adult sheep tendons, three techniques of tendon repair were tested biomechanically: the 'three figure-of-eight sutures' (a six-strand grasping technique), the 'locked cruciate repair' (a four-strand locked technique) and the 'combined technique' (a 10-strand repair using both the figure-of-eight and cruciate sutures). All repairs were tested to single-cycle tensile failure using a computerised tensometer. For each repair, the 2-mm gap force and the ultimate breaking (failure) force were recorded. Biomechanically, the combined repair was found to be the strongest regarding both gap and failure (P<0.025; two-tailed by the Mann-Whitney test). The combined 10-strand repair is stronger biomechanically than its grasping and locking components.

Quantification of Partial or Complete A4 Pulley Release With FDP Repair in Cadaveric Tendons

Repair of a lacerated flexor digitorum profundus (FDP) tendon underneath or just distal to the A4 pulley can be technically challenging, and success can be confounded by tendon triggering and scarring to the pulley. The purpose of this study was to quantify the effect of partial and complete A4 pulley release in the context of a lacerated and repaired FDP tendon just distal to the A4 pulley. Tendon biomechanics were tested in 6 cadaveric hands secured to a rigid frame, permitting measurement of tendon excursion, tendon force, and finger range of motion. After control testing, each finger had laceration and repair of the FDP tendon at the distal margin of the A4 pulley using a 6-strand core suture technique and epitendinous repair. Testing was then repeated after the following interventions: (1) intact A4 pulley, (2) release of the distal half of the A4 pulley, (3) complete release of the A4 pulley, and (4) continued proximal release of the sheath to the distal edge of A2 (release of C2, A3, and C1 pulleys). Release of the pulleys was performed by incision; no tissue was removed from the specimens. From full extension to full flexion, average FDP tendon excursion for all intact digits was 37.9 ± 1.5 mm, and tendon repair resulted in average tendon shortening of 1.6 ± 0.4 mm. Flexion lag increased from <1 mm to >4 mm with venting of the A4 pulley, complete A4 release, and proximal sheath release, respectively. Compared to the intact state, repair of the tendon with an intact A4 pulley, release of half the A4 pulley, complete A4 release, and proximal sheath release resulted in percentage increases in work of flexion of 11.5 ± 3.1%, 0.83 ± 2.8%, 2.6 ± 2.4%, and 3.25 ± 2.2%, respectively. After FDP laceration and repair in the region of the A4 pulley, work of flexion did not increase by more than 3% from control conditions after partial or complete A4 pulley release, and work of flexion was significantly less than that achieved by performing a repair and leaving the A4 pulley intact.

Zone II Combined Flexor Digitorum Superficialis and Flexor Digitorum Profundus Repair Distal to the A2 Pulley

Combined transection of both the flexor digitorum superficialis (FDS) and the flexor digitorum profundus (FDP) tendons distal to the A2 pulley is challenging due to the intimacy of the FDS–FDP relationship at that level. This report describes our surgical technique for repair of combined FDS and FDP transections following decussation of the FDS tendon. Each slip of the FDS is repaired using 5-0 or 6-0 polypropylene sutures in a Becker configuration, creating a 4-strand repair for each slip. Repair of the FDP tendon is performed using Winters' core-suture technique with looped 4-0 pseudomonofilament nylon suture, modified to achieve a locking loop and an 8-strand repair.

Outcome of early active mobilization after flexor tendons repair in zones II-V in hand.

Background:The functional outcome of a flexor tendon injury after repair depends on multiple factors. The postoperative management of tendon injuries has paved a sea through many mobilization protocols. The improved understanding of splinting techniques has promoted the understanding and implication of these mobilization protocols. We conducted a study to observe and record the results of early active mobilization of repaired flexor tendons in zones II–V.Materials and Methods:25 cases with 75 digits involving 129 flexor tendons including 8 flexor pollicis longus (FPL) tendons in zones II–V of thumb were subjected to the early active mobilization protocol. Eighteen (72%) patients were below 30 years of age. Twenty-four cases (96%) sustained injury by sharp instrument either accidentally or by assault. Ring and little finger were involved in 50% instances. In all digits, either a primary repair (n=26) or a delayed primary repair (n=49) was done. The repair was done with the modified Kessler core suture technique with locking epitendinous sutures with a knot inside the repair site, using polypropylene 3-0/4-0 sutures. An end-to-end repair of the cut nerves was done under loupe magnification using a 6-0/8-0 polyamide suture. The rehabilitation program adopted was a modification of Kleinert’s regimen, and Silfverskiold regimen. The final assessment was done at 14 weeks post repair using the Louisville system of Lister et al.Results:Eighteen of excellent results were attributed to ring and little fingers where there was a flexion lag of < 1 cm and an extension lag of < 15°. FPL showed 75% (n=6) excellent flexion. 63% (n=47) digits showed excellent results whereas good results were seen in 19% (n=14) digits. Nine percent (n=7) digits showed fair and the same number showed poor results. The cases where the median (n=4) or ulnar nerve (n=6) or both (n=3) were involved led to some deformity (clawing/ape thumb) at 6 months postoperatively. The cases with digital or common digital nerve involvement (n=7 with 17 digits) showed five excellent, two good, four fair, and six poor results. Complications included tendon ruptures in 2 (3%) cases (one thumb and one ring finger) and contracture in 2 (3%) cases whereas superficial infection and flap necrosis was seen in 1 case each.Conclusion:The early active mobilization of cut flexor tendons in zones II–V using the modified mobilization protocol has given good results, with minimal complications.

Effect of core suture technique and type on the gliding resistance during cyclic motion following flexor tendon repair: A cadaveric study

We investigated the effects of two suture techniques using three suture types in a human model in vitro. We obtained 60 flexor digitorum profundus (FDP) tendons from cadavers and measured the gliding resistance during 1,000 cycles of simulated flexion-extension motion and load to failure of six groups: the modified Kessler (MK) repair using 3-0 coated, braided polyester (Ethibond, Ethicon, Somerville, NJ), 3-0 coated, braided polyester/monofilament polyethylene composite (FiberWire®; Arthrex, Naples, FL), or 4-0 FiberWire; and the Massachusetts General Hospital (MGH) repair using 3-0 Ethibond, 3-0 FiberWire, or 4-0 FiberWire. The 3-0 Ethibond MGH suture had significantly higher ultimate load to failure than the 3-0 or 4-0 FiberWire MK suture. The 3-0 and 4-0 FiberWire MGH sutures had significantly higher load to failure than the three MK groups. The gliding resistances of the three MGH groups were significantly higher than that of the three corresponding MK groups. The MGH repair had more gliding resistance than an MK repair, even when comparing large diameter suture in the MK repair with smaller diameter suture in the MGH repair. In this study, suture technique was more important in predicting repair load to failure and gliding resistance than the nature or caliber of the suture material that was used.