Minimally invasive, endoscopic Achilles tendon reconstruction using semitendinosus and gracilis tendons with Endobutton stabilization.

BACKGROUND: Plantaris tendon, peronus brevis tendon and flexor hallucis longus tendon augmentation, commonly used in Achilles tendon rupture, often lead to weakening of injured foot and they require the immobilization after the surgery. It is essential to develop the technique, which gives no such limitation and allows for immediate functional improvement. METHODS: We present our method of minimally invasive, endoscopic Achilles tendon reconstruction using semitendinosus and gracilis tendons with Endobutton stabilization. RESULTS: Posterolateral and posteromedial portals were made approximately 3 cm above the posterosuperior part of the calcaneus to clean the area of the Achilles tendon endoscopically. Then the hamstrings are harvested and prepared for the "Endobutton" system. A midline incision of the skin is performed approximately 1 cm above the posterosuperior part of the calcaneus to approach to the posterosuperior part of the calcaneus. Then under fluoroscopy the calcaneus was drilled through using K-wire. The distal end of the graft equipped with an Endobutton loop was entered into the drilled tunnel in the calcaneus. Later, 8 consecutive skin incisions are performed. Proximal ends of the graft were brought out through the native Achilles tendon reaching medial and lateral skin incisions. The final step was to transfer and tie the graft ends through the most proximal skin incision. CONCLUSIONS: This minimally invasive, endoscopic technique allows reconstruction of the Achilles tendon using semitendinosus and gracilis tendons with Endobutton stabilization and can be used in so-called "difficult", resistant cases as a "salvage procedure".

[Secondary tendon reconstruction on the thumb]. / Sekundäre Sehnenrekonstruktionen am Daumen.

Closed tendon ruptures of the thumb that require secondary reconstruction can affect the extensor pollicis longus (EPL), extensor pollicis brevis (EPB) and flexor pollicis longus (FPL) tendons. Treatment of rupture of the EPB tendon consists of refixation to the bone and temporary transfixation of the joint. In the case of preexisting or posttraumatic arthrosis, definitive arthrodesis of the thumb is the best procedure. Closed ruptures of the EPL and FPL tendons at the wrist joint cannot be treated by direct tendon suture. Rupture of the EPL tendon occurs after distal radius fractures either due to protruding screws or following conservative treatment especially in undisplaced fractures. Transfer of the extensor indicis tendon to the distal EPL stump is a good option and free interposition of the palmaris longus tendon is a possible alternative. The tension should be adjusted to slight overcorrection, which can be checked intraoperatively by performing the tenodesis test. Closed FPL ruptures at the wrist typically occur 3-6 months after osteosynthesis of distal radius fractures with palmar plates and are mostly characterized by crepitation and pain lasting for several weeks. They can be prevented by premature plate removal, synovectomy and carpal tunnel release. For treatment of a ruptured FPL tendon in adult patients the options for tendon reconstruction should be weighed up against the less complicated tenodesis or arthrodesis of the thumb interphalangeal joint.

Myxoid tumor associated to migration of a suspensory fixation device of a reconstructed anterior cruciate ligament: a case report.

A 16-year-old male who had undergone 6 months before an anterior cruciate ligament (ACL) reconstruction with an autologous hamstring graft fixed with a suspensory fixation device (XoButton device; ConMed Linvatec, Largo, FL), complained of a slightly painful mass in the distal posterolateral aspect of the thigh. The knee was otherwise stable. A 79 × 60 × 17 mm multilobulated tumor surrounding the implant device was observed in magnetic resonance images. The revision arthroscopy showed an intact ACL graft. The tumor was excised through a longitudinal posterolateral approach. It had a myxoid appearance. The undamaged implant was also removed. Two months after surgery, the patient was already asymptomatic. Although most fixation device problems occur in the perioperative period due to an inadequate technique which may lead to graft instability, this case reminds clinicians of the possibility of later developing clinically relevant complications with suspensory fixation devices.

Complications after tendon transfers in the foot and ankle using bioabsorbable screws.

BACKGROUND: Tendon transfers are commonly used for correction of pathology or deformity of the foot and ankle. Bioabsorbable implants have been developed as an alternative to metal interference screws. The purpose of this study was to document complications following tendon transfers of the foot and ankle using bioabsorbable poly-L-lactide interference screws. METHODS: A retrospective chart review was used to identify patients in whom either of the 2 senior authors had performed a tendon transfer of the foot and ankle using a bioabsorbable interference screw between 1999 and 2005. A minimum of 6 months of follow-up was required for inclusion in the study. In all, 31 patients were identified who met the inclusion criteria with an average follow-up of 75 weeks. All screws were made of poly-L-lactide (PLLA). RESULTS: Complications were identified in 12 (39%) of patients. All of the complications reported were known complications of the tendon transfer procedure itself, and were not directly related to the bioabsorbable screw. CONCLUSIONS: Based on these early results, PLLA implants appear safe and effective for tendon transfers of the foot and ankle. However, until long-term outcomes are available, judicious use of these implants is recommended.

Malignant fibrous histiocytoma of the distal femur after an arthroscopic anterior cruciate ligament reconstruction: A case report and a review of the literature.

BACKGROUND: Malignant degeneration in association with orthopaedic implants is a known but rare complication. To our knowledge, no case of osseous malignant fibrous histiocytoma after anterior cruciate ligament reconstruction is reported in the literature. CASE PRESENTATION: We report a 29-year-old male Turkish patient who presented with severe pain in the operated knee joint 40 months after arthroscopic anterior cruciate ligament reconstruction. X-ray and MR imaging showed a large destructive tumor in the medial femoral condyle. Biopsy determined a malignant fibrous histiocytoma. After neoadjuvant chemotherapy, wide tumor resection and distal femur reconstruction with a silver-coated non-cemented tumor knee joint prosthesis was performed. Adjuvant chemotherapy was continued according to the EURAMOS 1 protocol. CONCLUSIONS: Though secondary malignant degeneration after orthopaedic implants or prostheses is not very likely, the attending physician should take this into consideration, especially if symptoms worsen severely over a short period of time.

[Implant-free anterior cruciate ligament reconstruction with diamond instruments. A biological and anatomic method for every ligament transplantation]. / Fremdmaterialfreier Kreuzbandersatz mit Diamanthohlschleifen. Eine biologische und anatomische Methode für alle Sehnentransplantate.

UNLABELLED: Hamstring and patella tendons are usually used for anterior cruciate ligament (ACL) reconstruction and fixed with foreign material, partially executed far from the original point of insertion. Besides the biomechanical questions bone defects are a severe problem in cases of revision. We developed a biological method with diamond cutting instruments for graft fixation with bone dowels near the native insertion. The graft is tensioned and fixed in 120 degrees knee flexion and is self-adapting in extension. The technique has been used in a large number of cases during a prospective study with a follow-up of 10 years for patella tendon and 4 years for hamstring tendon grafts. In this investigation 124 patients with bone-patellar tendon-bone (BPTB) grafts showed an International Knee Documentation Committee (IKDC) score A/B in 87% after a mean follow-up of 9.6 years, a Lachman test (maximum side-to-side difference) of 1.38+/-0.93 mm and a negative pivot shift test in 91% of the cases. Of the 147 patients with hamstring tendon grafts 89% had an IKDC score A/B after a mean follow-up of 4.3 years, a Lachman test of 1.14+/-0.76 mm and no pivot shift in 90% of the cases. The Tegner activity score decreased by -1.8 in both groups. CONCLUSION: This method allows a reliable biological press-fit fixation for every kind of graft near the original point of insertion, preventing bone defects, allowing early intensive rehabilitation and low costs.

A new anchoring technique for tibialis anterior tendon transfer.

Tibialis anterior tendon transfer was described as an effective method in the management of dynamic supination as well as prevention of clubfoot relapse in children. Different successful methods were described for anchoring the transferred tibialis anterior tendon; however, each of which has its own complications that were avoided by using this novel technique. This study included 26 feet in 18 patients, who underwent tibialis anterior tendon transfer as a part of management of their congenital clubfoot. The mean age was 3.6 years (ranging from 2.5 to 5 years), all patients were followed up for 6 to 30 months (mean = 14 months). The transferred tibialis anterior tendon was anchored in the third cuneiform using transfixing K wires. This novel technique resulted in successful and stable anchoring of the transferred tibialis anterior tendon. The transferred tendon was well palpated in all patients with active dorsiflexion, with no associated tendon rupture, anchoring problems, or wound complication. Our technique is secure, reliable, and economic with no special equipment needed. It could successfully avoid the plantar skin complications associated with pullout sutures and neurovascular injury.

Anatomic reconstruction of neglected Achilles tendon rupture with autogenous peroneal longus tendon by EndoButton fixation.

BACKGROUND: Neglected or chronic rupture of the Achilles tendon usually needs a reconstruction procedure. Many graft sources have been reported for this procedure, such as a proximal V-Y gastrocnemius tendon flap, flexor hallucis longus tendon, fascia lata, plantaris tendon, synthetic materials, and peroneus brevis. However, how to fix the graft at the calcaneal site remains controversial. METHODS: An alternative technique to anatomically reconstruct the Achilles tendon using an autogenous peroneal longus tendon with EndoButton-CL fixation at the calcaneal site for treatment of a patient who had a chronic neglected rupture of the Achilles tendon is described. RESULTS: The patient was allowed to begin gentle exercise, such as swimming and cycling 12 weeks after surgery, and encouraged to augment rehabilitation of hindfoot eversion and ankle plantar flexion. The ankle plantar flexion and hindfoot eversion strength was not reduced after active rehabilitation in 2.5 years of follow-up. CONCLUSIONS: Our technique reuses two small central incisions, thus, preserving skin integrity as much as possible to reduce wound breakdown or infection. The management of chronic or neglected Achilles tendon rupture by autogenous peroneal longus tendon with EndoButton-CL fixation at the calcaneal site is an anatomic and safe, but technically demanding technique.

Tendon transfer fixation in the foot and ankle: a biomechanical study.

BACKGROUND: Tendon transfers are often used in foot and ankle surgery. Different fixation devices and techniques have been described. The most recently developed ones are bone anchors and interference screws. MATERIALS AND METHODS: A biomechanical study was designed to compare tendon transfer fixation, using Corkscrew bone anchors 5 x 15.5 mm and Bio-interference screws (8 x 23 mm). Fifteen fresh cadaver specimens underwent both fixation techniques for split anterior tibial tendon transfer at the cuboid bone. All the specimens underwent standardized X-rays in order to evaluate mineral bone density using a standardized measurement system. All were tested until maximal load to failure. RESULTS: The ultimate load to failure of the tendon secured to the cuboid using anchors was 103 N (SD, 52), compared with 150 N (SD, 68) for tendons secured to the bone with interference screws (p = 0.003). No difference was found between the techniques that could be related to bone density. CONCLUSION: Interference screws provided greater strength than bone anchors. CLINICAL RELEVANCE: This study demonstrated increased strength in securing bone to tendon in vitro for SPLATT tendon transfer with interference screws as compared to suture anchors.

Tendon Transfer Surgery: Focus on .

Median and Ulnar nerve palsy is a devastating condition that compromise hand function. A procedure of tendon transfer may be helpful to restore the movements by linking palsy muscles to other muscles able to contract. Scientific discoveries and technological innovations have profoundly changed this kind of surgery; studies on sarcomeres, for example, changed the concept of tensioning. To date we know that muscle strength and its contraction capacity depends on many factors (not only tensioning) such as sarcomeres length, cellular cytoskeleton and extracellular matrix composition: all of these factors interact together and in a ways not still fully understood, determining the complex concept of "movement." Technology made possible the production of smaller and more complex prostheses so to open new frontiers for modulation of the tendon length during grasping. These devices, currently studied on computer models, on cadaver or on animals, behaved great impetus to research but are still not suitable for implantation in humans. Challenges are still numerous: for example obtain more biocompatible implantable device, find new surgical approach, new ways to obtain better results for this kind of patients.

[Anterior cruciate ligament reconstruction with semitendinosus tendon in children]. / Vorderer Kreuzbandersatz mit der Semitendinosussehne bei Kindern.

OBJECTIVE: To present the technique of arthroscopy-assisted anterior cruciate ligament (ACL) reconstruction in children with complete ACL rupture. INDICATIONS: The indications for surgery are intraligamentous ruptures of the ACL with persistent signs and symptoms due to instability in spite of a minimum 6-month trial with conservative management and reduction of sports activities. Other decision-making factors for surgery include secondary injuries to the menisci or limitation of daily activities due to the instability produced by the ACL rupture. The indication for surgical intervention has to be judged individually and carefully in younger children. CONTRAINDICATIONS: Poor compliance on the part of the patient to participate in postoperative rehabilitation. Overexpectations regarding the surgical outcome (ability to participate in professional sports without limitations). Younger age of the patient (Tanner stage 2 or younger maturity), without trial of conservative treatment over a period of 6 months. ACL rupture at the bone-ligament region (tibial or femoral), partial rupture or lengthening of the ACL without rupture; in these instances, the instability may improve with growth. SURGICAL TECHNIQUE: Diagnostic arthroscopy to evaluate the knee joint and to identify associated or secondary injuries to the menisci and articular cartilage. If possible, these injuries should be addressed in the same surgical session. Preparation and stripping of the semitendinosus tendon using a tendon stripper. The technique used is transepiphyseal with extraosseous fixation. Depending on the thickness, the semitendinosus tendon is either tripled or quadrupled and prepared for transplantation. Single-canal technique. The diameter of the canal has to be selected depending on the size of the child's knee (usually between 6-8 mm). The tendon transplant is placed such that the canal is also filled with the tendon in the epiphyseal part (tendon transplant length usually 7 cm). Tibial canal entry medial to the tibial tuberosity, entering the joint at the level of the anterior horn of lateral meniscus in the intercondylar notch. Optimal positioning confirmed by an intraoperative negative impingement test of the guiding pin before drilling. Femoral canal entry placed at the 10:00-10:30 o'clock position on the right side, and 01:30-02:00 o'clock position on the left side. Care must be taken to avoid injury to the perichondral ring. In younger children (Tanner stage 3 or lower), avoidance of fixation material transfixing the epiphysis - femoral fixation performed using endobutton and tibial fixation with the Suture-disc. In older children (Tanner stage 4 or above) alternative fixation methods are possible (interference screw). The fixation of the ACL tendon transplant is such that reconstruction is in minimal tension in 30 degrees flexion. POSTOPERATIVE MANAGEMENT: Postoperative treatment regimen in the first 6 weeks after surgery depends on the extent of additive surgeries (menisci, chondral injuries) performed in the same sitting. In the absence of associated injuries, weight bearing is gradually increased with the aim of achieving full weight bearing at the end of the 1st postoperative week. In case of additional meniscal sutures, knee flexion is restricted to 60 degrees maximum and non-weight bearing for 4 weeks is advised. Postoperative mobilization is performed using an adjustable knee orthesis. Between 4-6 weeks postoperatively, the permitted flexion is gradually increased to a maximum of 90 degrees and partial weight bearing is started. Full weight bearing and free movements with muscle training are started after 6 weeks. Avoidance of weight transmission on the flexed and rotated knee until 12 weeks postoperatively. Start with sports activities under supervision after 6 months, trial with professional sports activities after 9 months. RESULTS: 57 children with remaining growth potential around the knee underwent ACL reconstruction using the semitendinosus tendon at the Pediatric Orthopedic Unit, Department of Pediatric Surgery, Graz, Austria, between 2002-2007. 45 patients received ACL reconstruction with associated meniscal injuries. The described endobutton technique for fixation of the transplant has been performed since 2006. As the patients are under follow-up, the long-term effects of this technique on growth around the knee are, to date, not known. 30 patients were operated before 2006 using the bioresorbable interference screw for fixation by ACL reconstruction with the semtendinosus tendon. All these patients were at Tanner stage 4 or older. 15 of these cases were evaluated after completion of growth, and all showed a good to excellent outcome in Tegner, Lysholm and IKDC (International Knee Documentation Committee) Scores without any growth disturbances.

Strength of Interference Screw Fixation to Cuboid vs Pulvertaft Weave to Peroneus Brevis for Tibialis Posterior Tendon Transfer for Foot Drop.

BACKGROUND: Tibialis posterior (TP) tendon transfer is an effective treatment for foot drop. Currently, standard practice is to immobilize the ankle in a cast for 6 weeks nonweightbearing, risking postoperative stiffness. To assess whether early active dorsiflexion and protected weightbearing could be safe, the current study assessed tendon displacement under cyclic loading and load to failure, comparing the Pulvertaft weave (PW) to interference screw fixation (ISF) in a cadaveric foot model. METHODS: Twenty-four cadaveric ankles had TP tendon transfer performed, 12 with the PW technique and 12 with ISF to the cuboid. The TP tendon was cycled 1000 times at 50 to 150 N and then loaded to failure in a materials testing machine. Tendon displacement at the insertion site was recorded every 100 cycles. An independent t test and 2-way analysis of variance were performed to compare techniques, with a significance level of P < .05. RESULTS: Mean tendon displacement was similar in the PW group (2.9 ± 2.5 mm [mean ± SD]) compared with the ISF group (2.4 ± 1.1 mm), P = .35. One specimen in the ISF group failed early by tendon pullout. None of the PW group failed early, although displacement of 8.9 mm was observed in 1 specimen. Mean load to failure was 419.1 ± 82.6 N in the PW group in comparison to 499.4 ± 109.6 N in the ISF group, P = .06. CONCLUSION: For TP tendon transfer, ISF and PW techniques were comparable, with no differences in tendon displacement after cyclical loading or load to failure. Greater variability was observed in the PW group, suggesting it may be a less reliable technique. CLINICAL RELEVANCE: The results indicate that early active dorsiflexion and protected weightbearing may be safe for clinical evaluation, with potential benefits for the patient compared with cast immobilization.

Effect of pilot-hole size on the pullout strength of flexor digitorum longus transfer fixed with a bioabsorbable screw.

BACKGROUND: Fixation of tendon transfers with a bioabsorbable interference-fit screw has several advantages over other fixation methods: decreased dissection, operative time, and blood loss; preservation of tendon length; no interference with radiographic studies; no need for implant removal; and no barrier to revision surgery. Whether strength of fixation is affected by the size of the pilot hole has not been established. The purpose of this study was to determine the effect of pilot hole size on the pullout strength of a flexor digitorum longus (FDL) tendon secured into a bone analog using a 5.5-mm bioabsorbable screw. METHODS: Thirty FDL tendons were harvested from 15 cadaver specimens and secured into predrilled 4 x 4 x 4 cm bone cubes with a 5.5-mm Arthrex bioabsorbable screw (Arthrex, Naples, FL). The use of bone analog foam cubes ensured consistent porosity at the insertion site, eliminating the variations associated with varying bone densities of cadaver specimens. Pilot hole sizes studied were 5.0 mm, 5.5 mm, and 6.0 mm. Pullout tests were done with an servohydraulic testing frame (MTS, Eden Prairie, MN). RESULTS: There was no significant difference (p = 0.4) between the pullout forces and stresses among the three pilot hole sizes. All specimens failed at the interface between the FDL and the bioabsorbable screw. In the 6.0-mm pilot hole group, there was a trend for increased pullout strength with increased tendon size. CONCLUSIONS: With a bioabsorbable 5.5-mm screw used for FDL transfer, a pilot hole the same size or a half millimeter larger or smaller than the screw had no statistically significant effect on the strength of the construct, even with tendons of different sizes.

Description and validation of a navigation system for intra-operative evaluation of knee laxity.

This paper describes the features of KIN-nav, a navigation system specifically dedicated to intra-operative evaluation of knee laxity, and assesses the reliability of the system during surgery. The acquisition protocol for its intra-operative use, the original user interface, and the computational methods for elaboration of kinematic data are described in detail. Moreover, an extensive and specific validation of the system was performed in order to evaluate its intra-operative performance and usability. KIN-nav's reliability and accuracy were analyzed in a series of 79 patients undergoing ACL reconstruction. The intra-surgeon repeatability computed for ACL-deficient and reconstructed knees at different flexion angles was less than 0.6 degrees for varus-valgus (VV) rotation, less than 1 mm for AP translation, and less than 1.6 degrees for IE rotation. The inter-surgeon repeatability is less than 2 degrees for VV rotation, 5 degrees for internal-external rotation, and less than 3 mm for AP translation. The proposed method was fast (requiring an additional 10 minutes of surgical time on average), required only a short learning period (5 cases), was minimally invasive, and was robust from the numerical perspective. Our system clearly shows that the use of navigation systems for kinematic evaluation provides useful and complete information on the knee state and test performance, and is simple and reliable to use. The good repeatability in manual kinematic tests is an improvement on the present ability to discriminate knee kinematics intra-operatively, and thus offers the possibility of better discrimination between knee pathologies and the prospect of new surgical applications.

[Double-bundle technique - anatomic reconstruction of the anterior cruciate ligament]. / Die Zwei-Bündel-Technik - eine anatomische Rekonstruktion des vorderen Kreuzbandes.

OBJECTIVE: To improve the rotational stability of the knee by anatomic reconstruction of the anterior cruciate ligament by socalled double-bundle technique using anteromedial and posterolateral grafts from native semitendinosus and gracilis. The grafts are fixed with bioabsorbable screws utilizing aperture fixation. INDICATIONS: Complete tear of the anterior cruciate ligament with positive Lachman sign and pivot shift. CONTRAINDICATIONS: Open growth plate. Osteoarthritis > grade 1 according to Jäger & Wirth. Age > or = 50 years with low sports activity (relative contraindication). SURGICAL TECHNIQUE: Graft harvest of the semitendinosus and gracilis tendons via a 3-cm horizontal skin incision parallel to pes anserinus and preparation of the tendons as double-looped grafts. Arthroscopy, resection of the stump of the anterior cruciate ligament, and clearance of its origin and insertion. Tunnel placement by means of aiming devices in the following order: tibial posterolateral, tibial anteromedial, femoral anteromedial (transtibial or via the anteromedial portal in 120 degrees flexion), and femoral posterolateral (via additional medial arthroscopic portal). The anteromedial (semitendinosus tendon) and posterolateral (gracilis tendon) bundles are passed through the tunnels and fixed on the femoral side. Tibial fixation of the graft by bioresorbable interference screw with knee flexion of 45 degrees (anteromedial) and 10 degrees (posterolateral). POSTOPERATIVE MANAGEMENT: Depending on the degree of swelling, rehabilitation with partial weight bearing for 14 days and full range of motion. Return to sports after 6 months, no contact sports until 9 months. RESULTS: From May 2004 to June 2005, anatomic double-bundle reconstruction was performed in 19 patients (13 male, six female, average age 31 years [18-48 years]) with isolated anterior cruciate ligament rupture without concomitant lesions. Clinical follow-up examination on average at 21.3 months (16-30 months) postoperatively. The Lysholm Score improved from an average of 65.2 to 94.5 points (75-100 points). The IKDC (International Knee Documentation Committee) Score yielded nine very good and ten good results in the relevant subgroups of motion, effusion and ligament stability. Measurement of anteroposterior translation with the KT-1000 instrument at 134 N showed increased translation of 1.8 mm (-2 to 5 mm) compared to the contralateral knee.

Evaluate muscle tension using intramuscular pressure device in rabbit tibialis anterior model for improved tendon transfer surgery.

Quantitative evaluation of passive tension in a muscle is important in tendon transfer surgeries, however, currently appropriate intraoperative measurement techniques are lacking. OBJECTIVE: Intramuscular pressure (IMP) is explored as an application to access force. APPROACH: The tibialis anterior (TA) in New Zealand white rabbits (n = 9) was used to test the hypothesis of a strong correlation between the IMP, muscle force, and length. This study also helped to develop intraoperative techniques for future human studies evaluating various insertion techniques (parallel versus perpendicular). MAIN RESULTS: The Pearson correlation between IMP and force for all trials was 0.74 ± 0.30. Separating out the parallel insertion from the perpendicular insertion revealed a significantly higher correlation for parallel, 0.91 ± 0.13 versus 0.56 ± 0.32. SIGNIFICANCE: These data indicate IMP sensors can be used to assess force in a single muscle and the parallel insertion method should be used. New findings • What is the central question of this study? Successful outcomes of tendon and muscle transfers depend on proper muscle tension. A near linear relationship has been seen between muscle force and intramuscular pressure. This study aims to develop an intraoperative technique for assessing passive muscle tension using intramuscular pressure. • What is the main finding and its importance? The findings from this study reveal a high correlation between pressure and passive tension in a single muscle. The techniques developed in this study will allow the translation to a human model. The work will help to improve surgical outcomes and aim to retain muscle strength in the patient following procedures such as tendon and muscle transfers.

Pullout strength of a novel hybrid fixation technique (Tape Locking Screw™) in soft-tissue ACL reconstruction: A biomechanical study in human and porcine bone.

INTRODUCTION: A novel hybrid anterior cruciate ligament (ACL) reconstruction technique known as Tape Locking Screw™ (TLS) is gaining popularity. Utilizing a suspension-type construct in conjunction with an interference screw, this technique has demonstrated successful initial clinical results with the use of quadruple hamstring graft. However, there is currently limited data available on the biomechanical strength of this fixation. This study investigates the pullout strength of the construct in human distal femora as well as in a porcine model. The construct is tested in isolation, without the use of any graft. We hypothesized that the pullout strength of this construct would be similar to or better than current fixation systems available. MATERIALS AND METHODS: The Tape Locking Screw hybrid fixation system was implanted into twenty-two fresh frozen human distal femora (50-89 years old) randomized to 10×20mm titanium or polyether ether ketone (PEEK) screws by a single sports fellowship trained orthopedic surgeon. Given that the graft is secured to polyethylene terephthalate tape within the construct, the construct was implanted without any graft in order to isolate the device for biomechanical testing. After implantation, a tensile force was applied directly to the loop of tape at a loading rate of 5mm/min using an electromechanical testing system. The failure load was calculated from the resultant load-displacement curve. Specimens were then visually examined for mode of failure. Similar biomechanical tests were performed on sixteen porcine femora. RESULTS: In the human model, the mean pullout strength was 523±269N with the PEEK screw and 578±245N with the titanium screw. In the porcine femur model, mean strength was 616±177N with PEEK, 584±245N with titanium. There was no statistically significant difference in failure loads between these four groups. Tape slippage at the screw bone interface was the primary mode of failure in all the groups tested. DISCUSSION: Our results demonstrate that the hybrid technique provides excellent pullout strength in comparison to other soft-tissue ACL fixation methods, with tape slippage being the mode of failure in all specimens tested. This data, in addition to the advantages of the TLS system, support its consideration in the armamentarium of constructs available for soft-tissue ACL reconstruction. LEVEL OF EVIDENCE: Laboratory controlled study level 2.

[A Novel Technique for the Preparation of a 3- or 5-Stranded Hamstring Graft for Individualised Single-Bundle ACL or PCL Reconstruction]. / Neuartige Technik zur Präparation eines 3- oder 5-strängigen Hamstring-Transplantats für die individualisierte Single-Bundle-VKB- oder -HKB-Rekonstruktion.

Objective Development of a preparation technique for hamstring tendons to ensure a maximum of intraoperative flexibility during individualised cruciate ligament surgery. Indications Primary ACL- and PCL-reconstruction as well as cases of later revision. Method Three- or five-stranded grafts can be obtained with the use of semitendinosus and gracilis tendons with fiber tape enforcement and use of a conventional femoral cortical suspensory fixation device. Fibre tape and knotting style ensure free motion of the continous loop. Through its simplicity, the technique offers the highest grade of intraoperative scalability.

An in vitro study comparing the use of suture anchors and drill hole fixation for flexor digitorum longus transfer to the navicular.

BACKGROUND: The surgical management of posterior tibial tendon dysfunction often includes transfer of the flexor digitorum longus (FDL) tendon through a tunnel in the navicular. Fixation often is obtained by sewing the tendon back onto itself. The purpose of this study was to compare this standard method of fixation with suture anchor fixation, a technique that may be associated with less surgical morbidity, because it requires the harvesting of less tendon length. METHODS: FDL tendon transfer to the navicular was done in 13 fresh-frozen cadaver specimens. In six feet comprising the standard group, the FDL tendon was transected distal to the master knot of Henry, placed through a drill hole into the navicular, and sutured back onto itself. In seven feet the FDL tendon was transected proximal to the master knot of Henry, placed into a drill hole into the navicular, and fixed with a suture anchor. Load was applied to the proximal FDL muscle and tendon using a materials testing system (MTS) machine and peak load to failure was measured. RESULTS: The mean load to failure was 142.48 N +/- 38.06 N for the standard group and 142.12 N +/- 59.26 N for the suture anchor group (p = 0.305 for the Student-t test and p = 0.945 for the Mann-Whitney test). CONCLUSION: Transfer of the FDL tendon to the navicular using suture anchor fixation requires less tendon length yet provides similar fixation strength as compared to sewing the tendon back onto itself. However, suture anchors are considerably more expensive than sutures. CLINICAL IMPLICATIONS: Suture anchors allow comparable fixation of FDL tendon transfer into a navicular without the need to disrupt the master knot of Henry. This technique may be associated with less morbidity including a shorter incision, decreased risk of medial plantar nerve injury, and decreased loss of lesser toe plantarflexion strength secondary to maintenance of the normal interconnections between the flexor hallucis longus (FHL) and FDL tendons.