Tendon Ends Research Articles

Biomechanical analysis of an original repair of an achilles tendon rupture in dogs: preliminary results

Tendon rupture is a common injury in animals, which may lead to severe lameness and pain depending on severity and duration. Surgical repair consists in re-apposition of the tendon ends using vario...

Biomechanical comparison of two suturing techniques during Achilles tendinoplasty in dogs: preliminary results

Tendon rupture in animals is a frequent injury that may cause intense lameness and pain, depending on severity and duration. Reparative surgery consists in re-apposition of the tendon ends using va...

Achilles Tendon Rupture: Can the Tendon Gap on Ultrasound Scan Predict the Outcome of Functional Rehabilitation Program?

Background and objectives There is a growing use of functional rehabilitation programs for the treatment of Achilles tendon rupture. Factors such as patient age and level of activity have been used to guide the decision. One of the debated indications is the gap size between the ruptured ends of the tendon. This study aims to define any correlation between the amount of the initial gap between tendon ends and patients outcome treated with the functional rehabilitation program.Method A prospective case series study of all patients with acute Achilles tendon rupture treated non-surgically with the functional rehabilitation program between 2016 and 2018. The tendon gap was measured with an ultrasound scan on the initial presentation. Patients were followed for a minimum of 12 months and assessed for Achilles Tendon Rupture Score (ATRS), plantarflexion strength, and re-rupture rate. Results A total of 56 patients completed one-year follow-up, and 2 patients had re-ruptures. The mean plantar flexion gap was 13.7 mm. The mean ATRS at 12 months was 85.12. There was no statistically significant correlation between the final ATRS and the mean rupture gap.Conclusion The outcome following non-operative functional rehabilitation treatment of rupture Achilles tendon did not correlate with the size of the tendon gap, and authors recommend that decision on functional rehabilitation should not be based on these criteria.

A biomechanical comparison of Achilles tendon suture repair techniques: Locking Block Modified Krackow, Kessler, and Percutaneous Achilles Repair System with the early rehabilitation program in vitro bovine model

The Krackow technique has the advantage of high strength, though it is not minimally invasive. The "Locking Block Modified Krackow" (LBMK) peri-tendon fixation technique was designed for minimally invasive surgery. This study aimed to compare the biomechanics of LBMK with Kessler and Percutaneous Achilles Repair System (PARS) techniques using a simulated early rehabilitation program. Thirty-fresh bovine Achilles tendon specimens were randomly assigned to the LBMK, Kessler, and PARS groups (n = 10). In LBMK group, the main suture configuration was the LBMK technique, and the transverse suture was used as the secondary suture configuration. The Kessler group employed three suture configurations, two sagittal, one coronal plane. In the PARS group, two transverse and one locking sutures were placed at either end of the tendon. Each repaired specimen underwent two cyclic loading protocols (20-100N, 20-190N), 500 cycles, followed by measurement of the gap between the tendon ends. All specimens underwent a load-to-failure test at a 25mm/s stretching rate. After the first loading cycle, the average gaps of the LBMK, Kessler and PARS groups were 0.76 ± 0.44mm, 1.80 ± 0.82mm, and 2.66 ± 1.04mm, respectively. The LBMK group had a significantly reduced gap than the other groups (p < 0.01). The LBMK group gaps were all within 2mm. The Kessler and PARS groups had six, and two specimens within 2mm, respectively. After the second loading cycle, the average end gaps of the LBMK, Kessler, and PARS groups were 3.68 ± 1.08mm, 5.70 ± 0.89mm and 7.59 ± 1.26mm, respectively. The LBMK group had a significantly reduced average gap than the other groups (p < 0.01). The maximum load-to-failure was highest 732.8 ± 138N in the LBMK than the other groups (p < 0.01). The biomechanical strength of the LBMK suture was significantly greater than Kessler and PARS. The reduced gap in the LBMK group suggests superior resistance to gap formation, which may occur during early postoperative rehabilitation.

Our Experience in Oral Commissure Reconstruction After Surgical Excision of Stage 3 and Stage 4 Oral Cavity Malignancy

The upper and lower lips represent the most important functional and aesthetic anatomical structures of the lower segment of the face. The reconstructive aims are to restore the oral lining, oral competence and function (i.e. articulation, speech and mastication). Functional and aesthetic restoration of lip and oral commissure defects can be achieved using the composite radial free forearm flap (RFFF) with Palmaris longus tendon. To present the technique, we have used our experience with this form of reconstruction in 30 consecutive patients with lip and oral commissure defects who were surgically treated between 2012 and 2018. Reconstruction of the lip defect was done with RFFF with Palmaris longus tendon. The ends of the Palmaris longus tendon were passed intraorally and anchored to the remnant orbicularis oris muscle of the upper lip to provide adequate tension so that oral competency could be achieved and sagging of the commissure could be prevented, and in cases, where adequate orbicularis oris was not present, the tendon was sutured to the zygomatic prominence. The patients were followed for 1 year. In our study of 30 cases of stage 3 and stage 4 oral cavity squamous cell carcinoma, we did RFFF with Palmaris longus and found that the graft uptake was excellent, i.e. 93.33%. Flap failure occurred in only 2 out of the total 30 cases. Re-exploration of the flap was done, and venous congestion was the cause of flap failure. Re-anastomosis of the vessels was done, but still the flap could not be salvaged. Donor site healed satisfactorily without any complications except for scarring. All patients had excellent oral competence during rest, speaking and eating. Good sphincteric function was obtained in early post-operative days. Drooling or air leakage was seen only in 6 out of 30 cases after 1 year of follow-up. The patients’ articulation was near-normal. The aesthetic results were accepted by 24 patients. All patients were able to resume regular diet. No complications were observed such as dehiscence, fistula formation or abscess formation. The mouth opening was also adequate (2–3 finger width) in 24 out of 30 patients of oral commissure reconstruction. The RFFF with Palmaris longus has excellent viability. It is a secure and reliable reconstructive option which produced satisfactory aesthetic and functional results.

Treatment of Common Calcaneal Tendon Rupture Using a Central Gastrocnemius Turnover Aponeurotic Flap Technique in a Dog

AbstractA 9-year-old, intact male, German wirehaired pointer was referred for suspected Achilles tendon rupture 3 weeks after an injury. A three-loop pulley suture pattern combined with a locking loop suture reduced the gap between the tendon ends to 7 mm and a central gastrocnemius turnover aponeurotic flap was used to cover the remaining gap. A type II free-form methyl methacrylate transarticular external skeletal fixator was used to keep the tarsocrural joint in extension until 45 days postoperatively. Short- and long-term clinical and ultrasonographic evaluations showed gradual improvement in weight-bearing and progressive tendon healing. At 6 months after surgery, the dog had normal limb function and had returned to the previous activity level. To the authors' knowledge, this tendon repair technique has been described in humans and in one cat but has not yet been reported in dogs.

Using Q Suture to Enhance Resistance to Gap Formation and Tensile Strength of Repaired Flexor Tendons.

Peripheral epitendinous sutures are believed to enhance core suture strength in tendon repair and decrease the risk of gapping between tendon ends. Here Q suture, an alternative to peripheral sutures, is presented for the use in tendon repair. Its effects on gap formation and tensile strength of the repaired tendons were compared with conventional running peripheral sutures. Three 2-strand sutures and three 4-strand sutures were used in repairing porcine tendons. The time required for performing 2Q and running sutures were recorded. The repaired tendons were subjected to a cyclic loading test, and the cycle number, during which a 2-mm gap was formed, was determined. After the cyclic loading, the gap size at the tendon ends and the ultimate strength of the repaired tendons were measured. Augmentation with the Q sutures reduced the number of tendons showing 2-mm gaps at tendon ends during cyclic loading. With addition of Q sutures 2-strand sutures significantly increased the ultimate strength of the repaired tendons and 4-strand sutures decreased the gap distance at the repair site of tendons. The time required for performing 2Q sutures was significantly less than that for running sutures. Therefore, we conclude that the Q suture is efficient in enhancing the tensile resistance and tendon repair strength and can be an alternative to conventional peripheral sutures.

Treatment of tendinous mallet finger deformity with a part of the flexor digitorum profundus tendon.

To introduce and evaluate an updated surgical technique for the treatment of tendinous mallet finger deformity. From April 2017 to September 2018, 13 cases of tendinous mallet finger deformity were treated. All patients had zone I extensor tendon rupture, with no residual tendon at the insertion for suture, and no avulsion fracture in the distal phalanx. Extensor tendon insertion reconstruction was realized by suturing the transferred portion of the flexor digitorum profundus tendon with the proximal end of the extensor tendon via a constructed bone tunnel. The treatment efficacy of the enrolled patients was evaluated by using Dargan evaluation criteria post-operatively. All patients were followed up with an average duration of 10.6 months. At the last follow-up, 12 patients showed excellent function recovery and one case had unsatisfactory outcome according to the Dargan evaluation criteria. Satisfactory therapeutic outcome for the treatment of tendinous mallet finger deformity can be achieved by reconstructing extensor tendon insertion using a part of the flexor digitorum profundus tendon, implying that the proposed treatment method is worthy of clinical application.

The finite element analysis of the influence of the load change of the internal oblique muscle on the near end of the patellar tendon based on the three-dimensional image model of MRI

Medical image segmentation is an important step of medical image processing, which divides medical image into thousands of regions and extracts the regions of tissues and organs of interest. The accuracy of segmentation is very important for the follow-up processing of medical image and doctors’ ju dgment of the real situation of diseases. Medical image segmentation is a classic problem in the field of image segmentation. 3D image reconstruction technology is to obtain 3D structure information from 2D images of objects, to provide users with realistic 3D graphics, and to restore the prototype of objects, so that users can observe and analyze from multiple perspectives, which greatly improves the accuracy of measurement and the scientific accuracy of medical diagnosis, and plays a very important role in assisting doctors in clinical diagnosis. Based on the three-dimensional image model of MRI, the load variation of the internal oblique muscle can be applied to the finite element analysis of the near end of the patellar tendon.

Spontaneous Rupture of Extensor Pollicis Longus Tendon: Clinical and Occupational Implications, Treatment Approaches and Prognostic Outcome in Non-Rheumatoid Arthritis Patients: A Retrospective Study.

BackgroundSpontaneous rupture of extensor pollicis longus (EPL) tendon is a rare condition often found in patients actively having regular extensive use of hands and fingers especially the thumb. In this article, we report 7 cases of spontaneous rupture of EPL tendon and investigate the associated factors and treatment outcome.MethodsRetrospectively, the databases for the 7 cases were retrieved and studied. These cases represent all cases of spontaneous rupture of EPL in our institution. Demographic data, clinical presentation, any history of trauma or steroid injection, laboratory and clinical findings suggestive for rheumatoid arthritis, co-morbidities and imaging findings were obtained. In addition, the operative technique and findings were retrieved. Moreover, histopathological studies and follow-up assessment were included.ResultsSix males and one female were included. The mean age was 45.2 years. No prior history of trauma, rheumatological disease or steroid use was detected in any patient. All patients experienced prodromal pain in the radial side. Clinical examination was the most effective diagnostic measure. Magnetic resonance imaging (MRI) was used to confirm the diagnosis and to look for other abnormalities that may predispose to rupture. Five patients underwent extensor indicis proprius to EPL tendon transfer employing Pulvertaft weave technique and one patient underwent primary repair as there was a little gap in the tendon ends. In this study, one patient refused any treatment. All patients achieved a favorable outcome at the last follow-up.ConclusionDiagnosis of spontaneous ruptures of EPL tendon can be confirmed through clinical examination and MRI for patients with restricted thumb movement even with the absence of any identifiable predisposing risk factor. During surgery, detailed attention must be drawn towards the tendon ends which can have unusual gaps and bone abnormalities.

Influence of Interlocking Horizontal Mattress Epitendinous Suture Placement on Tendinous Biomechanical Properties in a Canine Common Calcaneal Laceration Model.

This article evaluates the effect of an interlocking horizontal mattress epitendinous suture (IHMES) in addition to a three-loop pulley (3LP) core suture for canine tendon repair. Twenty-eight cadaveric common calcaneal tendons were randomized, sharply transected and repaired with either a 3LP or 3LP + IHMES. Tensile loads required to create a 1- and 3-mm gap, yield, peak and failure loads, and mode of failure were analysed. Significance was set at p < 0.05. Mean ± standard deviation yield and failure force for 3LP + IHMES was 178.0 ± 45.3 N and 242.1 ± 47.8 N, respectively, which was significantly greater compared with 3LP alone, 97.9 ± 36.2 N and 119.3 ± 35.6 N (p < 0.0001). Occurrence of 3-mm gap formation was significantly less in the 3LP + IHMES group (p < 0.013). Mode of failure was significantly different between the groups (p < 0.001) with 3LP + IMHES patterns failing by suture breakage (13/14) compared with suture pull-through in the 3LP (11/14). Addition of an epitendinous suture pattern significantly reduced gap formation between tendon ends and significantly increased loads at yield (1.8 × ), peak (2.0 × ) and failure (2.0 × ) force of repairs. Use of an epitendinous suture should be considered to significantly increase biomechanical strength of repairs; however, further in vivo testing is necessary to evaluate its effect on tendinous blood supply.

Ultrasound assessment of extensor pollicis longus tendon rupture following distal radius fracture: a sonographic and surgical correlation.

Aim of the studyTo assess the features identified on ultrasound in patients presenting with suspected extensor pollicis longus tendon rupture, and correlate this with surgical findings.Material and methodsA retrospective case series review was performed in 11 patients (8 female, 3 male) with suspected extensor pollicis longus tendon rupture. All ultrasound examinations were performed by an experienced musculoskeletal radiologist using a high-resolution linear-array probe. The study evaluated the associated sonographic appearances of extensor pollicis longus tendon rupture and correlated with surgical findings.ResultsRupture of the extensor pollicis longus tendon was identified in all cases proximally at the level of Lister’s tubercle. The most common associated sonographic finding was an effusion in the sheath of compartment III (10 patients); 9 patients also had fluid within the sheath of compartment II. An empty tendon sheath was observed in 1 patient and tenosynovitis of the extensor pollicis longus sheath was demonstrated in 2 cases. In 9 patients, sonography revealed the retracted tendon ends as enlarged and hypoechoic with loss of their normal fibrillar appearance. Ultrasound depicted fracture involvement of Lister’s tubercle in 8 cases (compared to 4 cases identified radiographically). In the 8 cases that proceeded to operative intervention, all of these were confirmed as extensor pollicis longus tendon rupture.ConclusionUltrasound is a valuable tool in identifying patients with extensor pollicis longus tendon rupture, providing the surgeon with invaluable details with regard to the level of rupture to aid pre-operative planning. US identifies associated ancillary features of extensor pollicis longus tendon rupture and reliably detects fractures involving Lister’s tubercle.

The single-suture technique for anterior cruciate ligament graft preparation provides similar stability as a three-suture technique: a biomechanical in vitro study in a porcine model

PurposeNumerous techniques have been described for the tibial-sided graft preparation in anterior cruciate ligament (ACL) reconstruction. The use of less suture material for graft preparation is thought to improve ingrowth and to reduce the risk for infection. At the same time, the suture construct should be strong enough to resist the surgeon’s pull during tensioning of the transplant.MethodsIn total, 39 fresh-frozen procine deep flexor tendons were used and prepared as four-strand grafts. In the three-suture group (n = 19), graft preparation was performed using three tibial-sided sutures, with each tendon end sutured separately. In the one-suture group (n = 20), a modified graft preparation using only one tibial-sided suture was applied. Each sample underwent load-to-failure testing (Nmax) after cyclic pre-loading. To estimate intraoperative tension forces acting on the tibial-sided suture constructs, the maximal tension force of 26 volunteers on such a construct was measured using a load cell.ResultsThe biomechanical testing of the two different suture constructs showed a significantly higher load-to-failure for the three-suture group (711 N ± 91 N) compared to the one-suture group (347 N ± 24 N) (p = 0.0001). In both groups, the mode of failure was a tear of the suture in all samples. A failure of the suture–tendon interface was not observed in any case. The median maximal tension force on the construct applied by the 26 volunteers was 134 N (range 73–182 N).ConclusionThe presented single-suture tendon graft preparation resisted to smaller failure loads than the conventional three-suture technique. However, no failures in the suture–tendon interface were seen and the failure loads observed were far beyond the tension forces that can be expected intraoperatively. Hence, the single-suture graft preparation technique may be a valuable alternative to the conventional technique.

Posterior Elbow Capsulotomy and Triceps Lengthening for Elbow Extension Contracture in Children with Arthrogryposis Multiplex Congenita.

The posterior aspect of the distal end of the humerus and the olecranon are identified by palpation and exposed via a curvilinear incision over the posterior aspect of the elbow. Identifying the osseous landmarks can be challenging in some patients. The ulnar nerve is identified and protected. The triceps tendon is isolated, and z-lengthening is performed. Next, the posterior elbow capsule is incised proximal to the tip of the olecranon to expose the joint surface, and the arthrotomy is continued incrementally along the medial and lateral capsule until elbow flexion increases by ≥40°, or past 90° (maximum, 120°), with contact between the lengthened ends of the triceps tendon for repair. The triceps tendon is then repaired in the elongated position. After the wound is closed, the elbow is placed in flexion and immobilized in a cast. Alternative treatments include passive stretching exercises to increase elbow flexion. Elbow extension contractures result in substantial limitations in the activities of daily living for children with arthrogryposis multiplex congenita. Those who fail to attain at least 90° of elbow flexion with passive stretching in the first year of life benefit from posterior elbow release and triceps lengthening. In addition, children with <30° of passive elbow flexion are at risk of developing valgus instability of the elbow from passive flexion exercises because the axis of rotation of the elbow is difficult to detect. Once passive elbow flexion is attained, such children may be candidates for tendon transfers allowing active elbow flexion.

The Effect of Patellar Tendon Release on the Characteristics of Patellofemoral Joint Squat Movement: A Simulation Analysis

Objectives: This paper studies the patellar tendon release’s effect on the movement characteristics of the artificial patellofemoral joint squat to provide reference data for knee joint surgery. Methods: Firstly, the dynamic finite element model of the human knee joint under squatting was established. Secondly, in the above no-release models, the release of 30% of the attachment area at the upper end, the lower end, or both ends of the patellar tendon were conducted, respectively. Then the simulations of all above four models were conducted. Finally, the results of the simulation were compared and analyzed. Results: The simulation results show that, after releasing the patellar tendon (compared with the no-release simulation’s results), the relative flexion, medial-lateral rotation, medial-lateral tilt, and superior-inferior shift of the patella relative to the femur increased; the medial-lateral shift and anterior-posterior shift of the patella relative to the femur decreased. Conclusion: In this paper, the maximum flexion angle of the patella increased after the patellar tendon being released (compared with the no-release model), which indicated that the mobility of knee joint was improved after the patellar tendon release. The simulation data in this paper can provide technical reference for total knee arthroplasty.

Achilles tendon rupture repair: Biomechanical comparison of the locking block modified Krackow technique and the Giftbox technique

BackgroundOpen Giftbox repair of the Achilles tendon has good biomechanical advantages, but it is not minimally invasive. We designed a peritendon fixation technique, the “Locking Block Modified Krackow” (LBMK) technique, to meet minimally invasive needs. This study used a simulated protocol of early rehabilitation to compare the biomechanics of LBMK with those of the Giftbox technique. MethodsTwenty fresh bovine Achilles tendon specimens were randomly assigned to either the LBMK group or the Giftbox group. The LBMK technique and the Giftbox technique were used as the main suture configurations, and transverse sutures were used as secondary suture configurations in both groups. Each repaired specimen was subjected to two cyclic loading protocols (20–100 N, 20–190 N). The gapping between the tendon ends was measured after each stage of loading. Finally, all specimens underwent a load-to-failure test at a stretching rate of 25 mm/s. ResultsAfter the first loading stage, the mean tendon gapping was 0.76±0.44 mm in the LBMK group and 0.86 ± 0.47 mm in the Giftbox group (p = 0.620). After the second loading test, the average gapping measures of the LBMK and Giftbox groups were 3.8 ± 1.9 mm and 4.2 ± 2.2 mm, respectively (p = 0.466). Finally, the catastrophic load to failure was 732.8 ± 138 N in the LBMK group and 645.5 ± 121 N in the Giftbox group. The difference was statistically significant (p = 0.023). ConclusionBoth the LBMK and Giftbox techniques meet the requirements of early rehabilitation, but the suture strength in the LBMK group was significantly higher than that in the Giftbox group.

Anatomy of the Distal End of Flexor Digitorum Longus Tendon and Percutaneous Release Technique: A Cadaveric Study.

Background:The transfer of flexor-to-extensor is widely used to correct lesser toe deformity and joint instability. The flexor digitorum longus tendon (FDLT) is percutaneously transected at the distal end and then routed dorsally to the proximal phalanx. The transected tendon must have enough mobility and length for the transfer. The purpose of this study was to dissect the distal end of FDLT and identify the optimal technique to percutaneously release FDLT.Methods:Eight fresh adult forefoot specimens were dissected to describe the relationship between the tendon and the neurovascular bundle and measure the width and length of the distal end of FDLT. Another 7 specimens were used to create the percutaneous release model and test the strength required to pull out FDLT proximally. The tendons were randomly released at the base of the distal phalanx (BDP), the space of the distal interphalangeal joint (SDIP), and the neck of the middle phalanx (NMP).Results:At the distal interphalangeal (DIP) joint, the neurovascular bundle begins to migrate toward the center of the toe and branches off toward the center of the toe belly. The distal end of FDLT can be divided into 3 parts: the distal phalanx part (DPP), the capsule part (CP), and the middle phalanx part (MPP). There was a significant difference in width and length among the 3 parts. The strength required to pull out FDLT proximally was about 168, 96, and 20 N, respectively, for BDP, SDIP, and NMP.Conclusion:The distal end of FDLT can be anatomically described at 3 locations: DPP, CP, and MPP. The tight vinculum brevis and the distal capsule are strong enough to resist proximal retraction. Percutaneous release at NMP can be performed safely and effectively.Clinical Relevance:Percutaneous release at NMP can be performed safely and effectively during flexor-to-extensor transfer.

Achillessehnenruptur – Teil 1: Ätiologie und Diagnostik

The Achilles tendon is the strongest tendon in the human body. Rupture of the Achilles tendon prevents the transmission of forces from the calf muscles to the foot and thus the push-off phase of walking and running is no longer possible. The diagnostics of Achilles tendon rupture are typically based on the symptoms and clinical examination. A palpable gap and the Thompson test are sometimes difficult to evaluate in situations with a large hematoma. Benchmarking for adefinitive rupture is the inability to perform aone leg heel raise. Sonography is used to determine the localization of the Achilles tendon and during the dynamic examination enables detection of a possible adaptation of the tendon ends. Acomplete adaptation of the tendon ends gives the possibility of conservative treatment. Sonographic control examinations after 4 and 8weeks document the course of healing. A visible increase in volume, especially at the rupture site confirms a normal course of healing. Magnetic resonance imaging enables verification of an Achilles tendon rupture and provides more information about the tendon structure.

Effects of a Q Suture Technique on Resistance to Gap Formation and Tensile Strength of Repaired Tendons: An Ex Vivo Mechanical Study

The repair of digital flexor tendons following laceration should aim to prevent gapping at the repair site and restore the tensile strength of the tendons to facilitate postoperative movement. We present here a simple Q suture and test its effects on gap formation and tensile strength of the repaired tendons. Sixty porcine tendons were repaired with 3 2-strand sutures (Kessler, Kessler plus 2Q, and Kessler plus running sutures) and 3 4-strand sutures (double Kessler, double Kessler plus 2Q, and double Kessler plus running sutures). The specimens were subjected to a cyclic loading. At each cycle, the number of tendons that initiated gapping or formed a 2-mm gap at the repair site was determined. After the cyclic load testing, the gap distance between tendon ends and the ultimate strength of the repaired tendons was measured. In both 2-strand and 4-strand tendon repairs, augmentation by insertion of the 2Q sutures reduced the number of tendons that showed 2-mm gaps ends during loading. Compared with the single Kessler and Kessler plus running sutures, Kessler plus 2Q suture significantly increased the ultimate strength of the tendon repair. Compared with the double Kessler and double Kessler plus running sutures, double Kessler plus 2Q suture significantly decreased the gap distance at the repair site after cyclic loading. The Q suture technique effectively enhances the resistance to gap formation of 2-strand and 4-stand tendon repair. It also improves the tensile strength of 2-strand Kessler repairs. The Q suture is a simple technique that can resist gap formation and strengthen the tensile strength of the repaired tendons in the laboratory setting.

Effect of a continuous epitendinous suture as adjunct to three-loop pulley and locking-loop patterns for flexor tendon repair in a canine model.

To evaluate the effect of combining a continuous epitendinous suture with three-loop pulley (3LP) and locking-loop (LL) core patterns for flexor tendon repair. Ex vivo biomechanical study. Seventy-two cadaveric superficial digital flexor musculotendon (SDFT) units. Tendons were divided into four groups (n = 18/group). After sharp transection, SDFT were repaired with 3LP, LL, 3LP + epitendinous (E), or LL + E suture patterns. After preloading, repaired constructs were tested to failure. Video data acquisition allowed evaluation of failure mode and quantitation of gap formation. Yield, peak, and failure force were measured from force-displacement data. Significance was set at P < .05. Mode of failure did not differ between repairs with or without an epitendinous suture (P = .255). Gap formation was best prevented with 3LP compared with LL when used alone (P = .001). Mean yield force for 3LP, LL, 3LP + E, and LL + E were 91.4 N ± 25.4, 61.3 N ± 18.4, 195.2 N ± 66.0, 165.3 N ± 46.8, respectively. Tenorrhaphies combined with an epitendinous suture achieved higher yield (P < .0001), peak (P < .0001), and failure forces (P < .0001), without gapping between tendon ends. Addition of an epitendinous suture eliminated gapping between tendon ends until failure and increased resistance to loads tolerated at the repair site. The addition of an epitendinous suture may increase the strength of tendon repairs and resistance to gap formation over core suture use alone. The influence of epitendinous suture placement on tendinous healing and blood supply warrants in-vivo testing.