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Background: Ruptures of the tibialis anterior tendon are rare but can cause substantial functional deficiencies. The literature regarding the treatment of such injuries is very limited. Atraumatic ruptures often occur in the presence of an abnormal tendon structure, and retraction often makes end-to-end repair impossible. With traumatic lesions, the risk of developing both adhesions and scar tissue is high. Methods: This study assesses the results of a surgical reconstruction using the interposition of a semitendinosus tendon autograft in 12 patients. Three patients had a traumatic rupture, and 9 patients had an atraumatic rupture. In 8 patients, the procedure was carried out using a minimally invasive technique. Results: The average postoperative American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot score was 95.7 in the atraumatic group and 94.7 in the traumatic group. Active dorsiflexion was possible after 2 to 3 weeks. We believe that the interposition of a strong, healthy tendon facilitated healing and allowed early weight bearing. All patients had good recovery of dorsiflexion and gait. Conclusions: Repairing a ruptured tibialis anterior tendon using a semitendinosus autograft was a reliable technique and offered a good result. With the minimally invasive approach, there was no need to divide the extensor retinaculum, which we believe allowed faster recovery and reduced the risk of adhesions and wound healing problems. Level of Evidence: Level IV, retrospective case series. [ABSTRACT FROM AUTHOR]

Abstract: Patellar tendon rerupture is a relatively uncommon condition that severely compromises the function of the extensor mechanism of the knee. Few cases described in the literature does not show a unique mode of treatment for this type of lesion. We report the case of a young athlete with traumatic patellar tendon rerupture. The first rupture was treated with the use of Statak anchors. Following a second rerupture incident as a result of a sporting accodent, the tendon was reconstructed with the use of an autologous graft tendon of semitendinosus and biological augmentation with gracilis tendon. For both tendons the distal insertion part was preserved to facilitate the healing process. The treatment was completed with the application of a neutralization cerclage wire and with local injection of plateket reach plasma (PRP). At 12 months follow up, a full recovery of the structure and function of the extensor mechanism was observed and the patient was able to resume normal sports competitive activity. [Copyright &y& Elsevier]

Tenderness is the one of the most important attributes of beef with regards to the intent of consumers to repurchase. Beef tenderness is frequently measured objectively as Warner-Bratzler shear force. However, to better understand the genetics underlying tenderness, better descriptors were derived herein. Two traits, adjusted shear force and aging rate, were calculated to incorporate measures of Warner-Bratzler shear force repeated over aging time of 2 muscles, longissimus dorsi (LD) and semitendinosus (ST). Analysis of these traits indicated that the shear forces of the 2 muscles are lowly correlated and aging rate, as calculated, was not correlated with adjusted shear force. Breed, SNP, and QTL effects were analyzed for the 4 traits (2 traits X 2 muscles). For adjusted shear force, the QTL were located on cattle chromosomes BTA 5, 18, 25, and 29. With the exception of the QTL on BTA 5, the adjusted shear force QTL were observed for either the LD or the ST but not both muscles. The QTL for aging rate were located on BTA 1, 4, 7, 11, 13, 19, and 20. [ABSTRACT FROM AUTHOR]

Muscle injuries are the most common injuries in sports, with hamstring injuries accounting for 29% of all injuries in athletes. These injuries lead to prolonged impairment and have a reinjury risk of 12% to 31%. They range from mild muscle damage without loss of structural integrity to complete muscle tearing with fiber disruption. Novel MRI scores are increasingly being used and allow a more precise prediction of return to sport. In this article, the authors review the history, mechanisms of injury, and classification systems for hamstring injuries as well as present the latest evidence related to the management of hamstring injuries, including intramuscular and both proximal and distal insertional injuries. Indications for surgical treatment of certain proximal and distal avulsions, biological augmentation to the nonoperative treatment of midsubstance injuries, and advances in risk reduction and injury prevention are discussed. [ABSTRACT FROM PUBLISHER]

ABSTRACT The hamstring tendon autograft is one of the most commonly used graft choices in Anterior cruciate ligament (ACL) reconstruction. There are conflicting results regarding postoperative hamstring strength deficits in patients who have had a hamstring graft. The semitendinosus tendon has been shown to regenerate after harvesting for ACL autograft, suggesting that the muscle has the potential to regain normal function. However, no studies have been performed to define the microstructural changes that occur in the semitendinosus muscle after tendon resection. In this study, we hypothesized that fatty infiltration of the semitendinosus muscle after tendon harvest in New Zealand White rabbits increases postoperatively and remains constant or increases during the first year of repair. The semitendinosus tendon was unilaterally detached and harvested from 15 rabbits. Five rabbits were sacrificed at 3-, 6-, and 12-month intervals, and the semitendinosus muscle-tendon units were analyzed. The contralateral unoperated limb served as the control. The gross tendon and muscle dimensions and histologic percentage of fatty infiltration were measured. We found no significant difference in fatty infiltration at any time point between the control muscle and test specimens and that there was no progression of fatty infiltration over time. If these results hold true in humans, natural repair of the hamstring muscle following tendon harvest during ACL autograft reconstruction is not inhibited by fatty infiltration. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1234-1239, 2013 [ABSTRACT FROM AUTHOR]

Abstract: The composition of three porcine muscles (Longissimus thoracis: LT, Semitendinosus: ST, Masseter: MS) was characterized and its link with muscle quality was evaluated. The LT muscle had a higher content of tyrosine, tryptophan, and carbohydrates and a lower content of vitamin E and haem iron than the MS muscle, while the ST had similar composition to MS but a lower content of haem iron. Large differences between muscles were observed in relative amounts of most of the major fatty acids. The LT muscle had higher saturated fatty acids (SFA) and n−6:n−3 fatty acid ratio, and lower polyunsaturated fatty acids (PUFA), PUFA:SFA ratio, unsaturation index and average fatty acid chain length than the ST and MS muscles. Muscle pH, redness and chroma were positively correlated with vitamin E and unsaturated lipids and negatively correlated with tyrosine, tryptophan, carbohydrates and saturated lipids, whereas muscle lightness and expressible juice showed similar correlations but an opposite sign with these variables. [Copyright &y& Elsevier]

Abstract: Three porcine muscles (Longissimus thoracis, Semitendinosus, Masseter), known to have large differences in biochemical and histological traits, were fully characterized and the link between muscle structure and quality evaluated. The oxidative Masseter had more pigment, higher content of metmyoglobin, haem iron, protein and collagen, and was redder with higher fibre numbers, fibre circularity, pH and water holding capacity than the glycolytic Longissimus. Fibre type distribution showed predominance of type IIB in Longissimus and Semitendinosus white, type I in Semitendinosus red and IIA in Masseter. Type I fibres were larger than type IIB and IIA in Semitendinosus and Masseter, respectively, but not in the Longissimus, indicating that fibre size is muscle dependent. Muscle redness was positively correlated with type I fibre traits, haem iron and metmyoglobin, and negatively associated with type II fibre characteristics, non-haem iron and oxymyoglobin. Expressible juice had positive correlation with fibre size and negative with fibre number and connective tissue. [Copyright &y& Elsevier]

Purpose: Primary aim of the study was analysis of hamstring tendon regeneration after anterior cruciate ligament reconstruction (ACLR). Secondary aim was analysis of isokinetic muscle strength in relation to hamstring regeneration. The hypothesis was that regeneration of hamstring tendons after ACLR occurs and that regenerated hamstring tendons contribute to isokinetic hamstring strength with regeneration distal to the knee joint line. Methods: Twenty-two patients scheduled for ACLR underwent prospective MRI analysis of both legs. MRI parameters were tendon regeneration and morphology, muscle retraction and muscle cross-sectional area. A double-blind, prospective analysis of isokinetic quadriceps and hamstrings strength was performed. Results: Regeneration of the gracilis tendon after ACLR occurred in all patients. Regeneration of the semitendinosus tendon occurred in 14 patients. At 1 year, the surface area of the semitendinosus and gracilis muscle decreased compared to both preoperatively ( P < 0.01) and the contralateral leg ( P < 0.01). The cross-sectional area of the semitendinosus muscle decreased in the absence of tendon regeneration ( P = 0.05). The cross-sectional area of the gracilis muscle was greater in case of regeneration distal to the joint line ( P = 0.01). Muscle retraction of the semitendinosus muscle was increased in case of nonregeneration ( P = 0.02). There was no significant relationship between isokinetic flexion strength and tendon regeneration. Conclusion: Hamstring tendons regenerated after harvest of both semitendinosus and gracilis tendons for ACLR. There was no relation between isokinetic flexion strength and tendon regeneration. Level of evidence: Prognostic study, Level II. [ABSTRACT FROM AUTHOR]

Background: There are potential drawbacks and complications associated with using the anterior approach to harvest the hamstring tendon as an autograft source for anterior cruciate ligament (ACL) and medial patellofemoral ligament (MPFL) reconstruction. A posterior harvest technique has been described as an alternative to an anterior approach in skeletally mature patients. The 2 approaches have not been compared in adolescents., Purpose: We sought to compare the incision size and harvested tendon length produced by anterior and posterior hamstring harvest techniques in an adolescent population., Methods: After obtaining consent, we prospectively collected data on a consecutive series of 115 adolescents undergoing ACL or MPFL reconstruction, including the length of the incision and of the harvested hamstring tendon. Demographic information including age, sex, and body mass index (BMI) was collected at the time of surgery., Results: The mean age at the time of surgery was 14.3 ± 1.8 years (range: 9-21 years), and 43% (N = 50) of participants were male. Of the 115 hamstring autografts, 26 were harvested anteriorly and 89 were harvested posteriorly. Neither mean semitendinosus length nor mean gracilis length was significantly different when harvested anteriorly versus posteriorly. The posterior harvest group had a mean incision length that was significantly smaller than that of the anterior harvest group. No iatrogenic nerve injuries or neurovascular complications were observed in either group., Conclusion: A posterior incision for hamstring autograft harvest provided an alternative approach in adolescents, which resulted in a 20% smaller incision than an anterior approach. For procedures such as MPFL reconstruction that do not require concomitant anteromedial work, posterior hamstring harvest may be used to improve cosmesis while producing viable hamstring autograft tissue for surgical reconstruction., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: PDF has relationships with Wolters Kluwer Health, Clinical Orthopedics and Related Research, Research in OsteoChondritis of the Knee (ROCK), and Current Opinion in Pediatrics. DWG reports relationships with Arthrex and Pega Medical. AHA, LMS, and MRH report no potential conflicts of interests., (© The Author(s) 2022.)

Introduction: Post-traumatic lesions of the carpus (scapholunate rupture, scaphoid non-union) frequently evolve into disabling osteoarthritis (scapholunate advanced collapse or scaphoid non-union advanced collapse: SLAC or SNAC wrist). Proximal row carpectomy (PRC) is a reliable option but with poorer prognosis in case of osteoarthritis of the distal radius or capitate head. In such situations, radiocarpal arthrodesis may be necessary, sacrificing wrist motion. To circumvent this limitation, we propose a new procedure consisting in arthroscopic PRC and replacing the proximal row by tendon graft., Methods: This was a study on 16 cadaver specimens. A scapholunate pin was introduced via an approach into the anatomical snuffbox and used as a guide for a cannulated drill bit (9mm) to create a tunnel through the proximal row. The arthroscope and a reamer were introduced into the tunnel via its radial and ulnar ends. PRC was performed under arthroscopic control. The gracilis and semitendinosus tendons were harvested and folded so as to obtain a graft with the same length and diameter as the proximal row. The graft was threaded through the radial approach and fixed to the capsule., Results: Mean procedure time was 68min. There was no pre- to postoperative difference in joint motion or carpal height. On radiocinematography, the graft was stable between the radius and the second row of the carpus. The radial and ulnar sensory branches, median nerve and radial artery were intact at end of procedure., Discussion: This technique could be a solution in SLAC or SNAC wrist with osteoarthritis of the capitate head or radial glenoid. It also conserves carpal height. Being arthroscopic, the procedure avoids the major edema observed after a dorsal approach of the carpus, and also ensures graft stability, since the radiocarpal ligaments are conserved. Harvesting from a second anatomical site and the in vivo fate of the transplant are two issues that need to be discussed., Conclusion: This anatomical study paves the way for clinical experimentation., Level of Evidence: IV., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Temporal biomechanical and physiological responses to physical activity vary between individual hamstrings components as well as between exercises, suggesting that hamstring muscles operate differently, and over different lengths, between tasks. Nevertheless, the force-length properties of these muscles have not been thoroughly investigated. The present review examines the factors influencing the hamstrings' force-length properties and relates them to in vivo function. A search in four databases was performed for studies that examined relations between muscle length and force, torque, activation, or moment arm of hamstring muscles. Evidence was collated in relation to force-length relationships at a sarcomere/fiber level and then moment arm-length, activation-length, and torque-joint angle relations. Five forward simulation models were also used to predict force-length and torque-length relations of hamstring muscles. The results show that, due to architectural differences alone, semitendinosus (ST) produces less peak force and has a flatter active (contractile) fiber force-length relation than both biceps femoris long head (BFlh) and semimembranosus (SM), however BFlh and SM contribute greater forces through much of the hip and knee joint ranges of motion. The hamstrings' maximum moment arms are greater at the hip than knee, so the muscles tend to act more as force producers at the hip but generate greater joint rotation and angular velocity at the knee for a given muscle shortening length and speed. However, SM moment arm is longer than SM and BFlh, partially alleviating its reduced force capacity but also reducing its otherwise substantial excursion potential. The current evidence, bound by the limitations of electromyography techniques, suggests that joint angle-dependent activation variations have minimal impact on force-length or torque-angle relations. During daily activities such as walking or sitting down, the hamstrings appear to operate on the ascending limbs of their force-length relations while knee flexion exercises performed with hip angles 45-90° promote more optimal force generation. Exercises requiring hip flexion at 45-120° and knee extension 45-0° (e.g. sprint running) may therefore evoke greater muscle forces and, speculatively, provide a more optimum adaptive stimulus. Finally, increases in resistance to stretch during hip flexion beyond 45° result mainly from SM and BFlh muscles., (© 2022. The Author(s).)

Abstract: 1H-high resolution magic angle spinning-nuclear magnetic resonance spectroscopy was employed to gain the metabolic profile of longissimus dorsi and semitendinosus muscles of four different breeds: Chianina, Holstein Friesian, Maremmana and Buffalo. Principal component analysis, partial least squares projection to latent structure – discriminant analysis and orthogonal partial least squares projection to latent structure – discriminant analysis were used to build models capable of discriminating the muscle type according to the breed. Data analysis led to an excellent classification for Buffalo and Chianina, while for Holstein Friesian the separation was lower. In the case of Maremmana the use of intelligent bucketing was necessary due to some resonances shifting allowed improvement of the discrimination ability. Finally, by using the Variable Importance in Projection values the metabolites relevant for the classification were identified. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to understand the detailed architectural properties of the human hamstring muscles. The long (BFlh) and short (BFsh) head of biceps femoris, semimembranosus (SM) and semitendinosus (ST) muscles were dissected and removed from their origins in eight cadaveric specimens (age 67.8±4.3years). Mean fiber length, sarcomere length, physiological cross-section area and pennation angle were measured. These data were then used to calculate a similarity index (δ) between pairs of muscles. The results indicated moderate similarity between BFlh and BFsh (δ =0.54) and between BFlh and SM (δ =0.35). In contrast, similarity was low between SM and ST (δ =0.98) and between BFlh and SM (δ =1.17). The fascicle length/muscle length ratio was higher for the ST (0.58) and BFsh (0.50) compared with the BFlh (0.27) and SM (0.22). There were, however, high inter-correlations between individual muscle architecture values, especially for muscle thickness and fascicle length data sets. Prediction of the whole hamstring architecture was achieved by combining data from all four muscles. These data show different designs of the hamstring muscles, especially between the SM and ST (medial) and BFlh and BFsh (lateral) muscles. Modeling the hamstrings as one muscle group by assuming uniform inter-muscular architecture yields less accurate representation of human hamstring muscle function. [Copyright &y& Elsevier]

Abstract: Neglected rupture of the patellar tendon is rare but becomes more difficult to repair the longer it is left untreated. The most common rupture sites are the inferior pole of the patella and distal insertion. Proximal retraction of the patella and extensor mechanism adhesions makes the treatment more difficult than acute tendon rupture. We report two patients with neglected patellar tendon rupture treated by reconstruction and restoration using semitendinosus–gracilis (STG) tendons with preserved distal insertions. Preserved distal insertion provided sufficient blood supply to accelerate healing, while combined fixation with tension-reducing wire, offered the initial stability of the closed-loop sutured tendon. Both patients reacquired near normal strength and stability of the patellar tendon and restoration of function after operation and rehabilitation. [Copyright &y& Elsevier]

Background: Previous studies are contradictory in terms of the function, regeneration potential, insertion point, and crosssectional area of the semitendinosus and gracilis tendons after harvest for anterior cruciate ligament (ACL) reconstruction. Hypotheses: In the long term, the tendons will regenerate in most patients with a more proximal point of insertion, the crosssectional area of the tendons will be smaller compared with the nonoperated contralateral side, and the patients will be weaker in terms of the internal rotation and deep flexion of the knee. Study Design: Case series; Level of evidence, 4. Methods: Nineteen patients (9 women and 10 men) who had undergone ACL reconstruction a minimum of 6 years earlier, median 8.5 years (range, 6-11 years), with ipsilateral semitendinosus and gracilis autografts, underwent bilateral magnetic resonance imaging (MRI) of their knees. An experienced, independent musculoskeletal radiologist evaluated all MRI examinations. To evaluate the function, strength measurements in deep knee flexion and internal rotation were performed using an isokinetic strength-testing machine. Results: The semitendinosus tendon had regenerated in 17 of 19 (89%) patients and the gracilis tendon in 18 of 19 (95%) patients, as seen on MRI. There were no significant differences between the point of insertion for the tendons on the operated and nonoperated sides. The cross-sectional areas of the regenerated tendons revealed no significant differences compared with the normal tendons on the contralateral side, as measured 4 cm above the joint line. The patients were significantly weaker in terms of deep knee flexion at 60 and 180 deg/sec, but they were stronger in terms of internal rotation of the tibia at 60 deg/sec in the operated leg compared with the nonoperated leg. Conclusion: The semitendinosus and gracilis tendons regenerated in the majority of patients and regained an almost normal point of insertion on the pes anserinus a minimum of 6 years after harvest. The regenerated tendons had a cross-sectional area similar to that on the nonoperated contralateral side. The patients revealed a strength deficit in deep knee flexion but not in internal rotation. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the outcomes following reconstruction of the chronic Achilles tendon ruptures with large gaps (>6 cm) using free semitendinosus tendon graft transfer. Methods: There were 11 consecutive patients underwent the above-mentioned surgical technique for the treatment of chronically ruptured Achilles tendon contributed in current study and were followed up prospectively for a mean of 25 ± 3 months. The intraoperative tendon defect was greater than 6 cm in all of the patients. Functional and clinical assessment was performed using The American Orthopaedic Foot and Ankle Society (AOFAS) and Achilles Tendon Rupture Score (ATRS). Results: The average AOFAS and ATRS improved significantly from 70 ± 5 and 32 ± 6 preoperatively, to 92 ± 5 and 89 ± 4 points post-operatively ( P = 0.001). The range of dorsiflexion was significantly limited on the operated side (13 ± 4° vs. 17 ± 4°) ( P = 0.04). All patients were able to stand on the tiptoe of injured leg, and no patient walked with a visible limp. Post-operative complications included one patient with symptomatic DVT and 2 patients with superficial infection treated nonoperatively. Conclusions: The technique offers good clinical and functional outcomes and is safe. Reconstruction of the chronic Achilles tendon ruptures with free semitendinosus tendon graft in patients with defects greater than 6 cm is recommended. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the tendinous inscription (TI) of the human semitendinosus (ST) muscle using dissection (cadavers) and ultrasound (in vivo). Ultrasonography (US) scans were taken in 18 young males at rest and at maximum voluntary contraction (MVC). Further, the ST was dissected and removed from its origins in 10 cadaveric specimens (5 cadavers). The cadaveric long arm of the TI was 6.67 ± 0.64 cm (6.45 ± 1.21 in US) while the shorter arm was 2.39 ± 0.38 cm (1.99 ± 0.75 in US). The angle formed by the two TI arms ranged from 53.19 (US) to 56.05° (cadavers) while more superficial fascicles intersected the inscription at significantly higher angles (range 31.98 ± 6.15 to 34.69 ± 7.71°) compared with deeper fascicles (p < 0.05). Fascicle length did not differ between compartments, but it was significantly smaller in superficial compared with deeper layers (p < 0.05). With the exception of the angle between the TI arm and the deep aponeurosis, all measured angles as well as the length of the long arm of the TI increased significantly from rest to MVC (p < 0.05). The role of the TI probably lies in the local interconnections with the fascicles of either compartment, which upon contraction is such that the ST muscle contracts as one muscle. However, the TI arm morphology changes from rest to MVC, indicating a nonuniform displacement of the TI, mainly between the superficial and deeper layers of the muscle. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Slices of beef eye of round were sous-vide cooked for 3, 6, 9, and 12 hours at 56, 58, and 60°C. The results showed that descriptors from a sensory descriptive analysis were divided into two groups based on response to heat treatment. In one group (12 descriptors including juiciness), the intensity of the descriptors increased (or decreased) with both time and temperature. In the other (6 descriptors including tenderness), the intensity increased with temperature but decreased with time (or decreased with temperature but increased with time). The sensory properties of the cooked beef corresponding to the descriptors in the two groups can consequently not be optimized simultaneously, and a compromise between, for example, tenderness and juiciness, is necessary. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate muscle torque, lower extremity coordination, and knee laxity after ACL reconstruction comparing patients operated on with semitendinosus graft (ST) and patients with combined semitendinosus and gracilis (STGR) grafts. Methods: Forty-six subjects who underwent ST ( n = 23) or STGR harvest ( n = 23) ACL reconstruction participated in this study. Quadriceps and hamstring torque were recorded using an isokinetic dynamometer. The anterior tibial translation was measured using the Kneelax 3 Arthrometer. The eccentric and concentric motor coordination was tested by multi-joint lower-limb tracking-trajectory test. All measurements were taken 12 months after surgery. Side-to-side differences were determined for all subjects. Results: Side-to-side differences in extensor peak torque at 180°/s and 60°/s did not differ between semitendinosus (ST) and semitendinosus + gracilis (STGR) groups (n.s.). However, side-to-side differences in flexor peak torque were significantly higher at 60°/s for the STGR group than the ST group ( P = 0.002). Side-to-side differences in eccentric and concentric parts of tracking-trajectory test and anterior tibial translation did not differ between the STGR and the ST groups (n.s.). Conclusion: The outcomes of this study suggested that additional harvest of gracilis did not influence lower extremity motor control, quadriceps muscle torque, and anterior tibial translation; however, it affected knee flexion isokinetic torque negatively at low angular velocity. This finding could be important for functional activity or sports with high demands on hamstring muscle strength. It is recommended that gracilis muscle should be preserved as possible during ACL reconstruction. Level of evidence: Prospective comparative study, Level II. [ABSTRACT FROM AUTHOR]

Habitual or recurrent dislocation of the patella in the skeletally immature patient is a particularly demanding problem since the etiology is frequently multifactorial. The surgical techniques successfully performed in adults with patellar instability may risk injury to an open growth plate if applied to children. We present a technique that preserves femoral and patellar insertion anatomy of medial patellofemoral ligament (MPFL) using a free semitendinosus autograft together with tenodesis to the adductor magnus tendon without damaging open physis on the patellar attachment of MPFL. A 3-cm long longitudinal skin incision is performed 10 mm distal to the tibial tuberosity on the anteromedial side. The semitendinosus tendon is harvested with the stripper. The semitendinosus tendon is placed on a preparation board and cleaned of muscle tissue. The usable part of the tendon should be at least 20 cm long and 4 mm wide. The two free ends of the graft are sutured with Krakow technique. A medial longitudinal incision 2 cm in length is made to expose the MPFL and to abrade the patellar attachment of vastus medialis obliquus. The first patellar tunnel is created with 4.5 mm drill at the mid aspect of the medial patella in the anteroposterior and proximal-distal direction. The drill hole is formed parallel to the articular surface of the center of the patella. The second tunnel is created with 3.2 mm drill and the entry point is localized at the center of the patella. These two tunnels intersect to form a single tunnel. The semitendinosus autograft is run through the bone tunnel in the patella. Double-stranded semitendinosus autograft is placed in the presynovial fatty plane between the second and the third layer of the medial retinaculum, and tenodesis to adductor magnus tendon is applied by a moderate medial force with the knee flexed at 30°. Aftercare includes immobilization of the joint limited to 30° flexion using an above-knee splint for 2 weeks. No recurrent dislocation was observed in three patients (4 knees) at a mean follow-up time of 17.7 months. Both range of motion and radiological finding were restored to normal limits. [ABSTRACT FROM AUTHOR]

Abstract: The potential of near-infrared (NIR) hyperspectral imaging system coupled with multivariate analysis was evaluated for discriminating three types of lamb muscles. Samples from semitendinosus (ST), Longissimus dorsi (LD) and Psoas Major (PM) of Charollais breed were imaged by a pushbroom hyperspectral imaging system with a spectral range of 900–1700nm. Principal component analysis (PCA) was used for dimensionality reduction, wavelength selection and visualizing hyperspectral data. Six optimal wavelengths (934, 974, 1074, 1141, 1211 and 1308nm) were selected from the eigenvector plot of PCA and then used for discrimination purpose. The results showed that it was possible to discriminate lamb muscles with overall accuracy of 100% using NIR hyperspectral reflectance spectra. An image processing algorithm was also developed for visualizing classification results in a pixel-wise scale with a high overall accuracy. [Copyright &y& Elsevier]

Semimembranosus (SM) muscle as well as Semi- tendinosus-Gracilis (STG) tendon have the same role in knee flexion and tibial internal rotation. Because STG tendons are generally used for anterior cruciate ligament (ACL) reconstruction, some compensational changes in SM muscle might have been induced. The purpose of this study was to investigate the changes of SM muscle affected by harvesting STG tendons. 10 Wistar- strain male rats were divided into control (C) and STG-dissected (STG) groups. Left STG tendons including the distal half of muscle portions were dissected in group STG and only skin incision was performed in group C. 4 weeks after the treat- ments, fiber types classification anc ultrastructural observations were performed. In group STG the decrease of type Ha (fast-twitch fiber with high oxidative capacity) was observed in deep layers of SM muscle (p<0.01). In ultrastructural observations, the increase in lipid droplets and mitochondria and the irregularity of Z disc were observed in deep layers. These me rphological changes indicated that the mechan cal loading might increase in SM muscle after harvesting of STG. Because of minor injuries in SM muscle, hamstring strength exercise at early stage of rehabilitation program should be carefully performed following ACL reconstruction using STG tendons in clinical practice. [ABSTRACT FROM AUTHOR]

The purposes of this paper are to summarize the concepts relating to the use of a combined intra-articular and extra-articular reconstructive procedure in the arthroscopic treatment of a torn ACL and to review several operative techniques utilizing gracilis and semitendinosus tendons that are currently in use to treat this instability. The highly satisfactory results obtained over the time show that a combination of intra- and extra-articular procedures for ACL reconstruction is a valid surgical option. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to compare the results 2 years after anterior cruciate ligament (ACL) reconstruction using a hamstring tendon (HT) autograft in patients operated within 5 months after the injury (Group A) and patients operated more than 24 months after the injury (Group B). Methods: Sixty-one patients (27 women, 34 men), with a unilateral ACL rupture, underwent reconstructive surgery using semitendinosus (ST) or semitendinosus and gracilis (ST/G) autografts. Thirty patients (Group A) were operated on within 5 months median 3 (2-5) after the injury, and 31 patients (Group B) were operated on more than 24 months median 30 (24-48) after the injury. The follow-up examination was performed after a median of 25 months (18-43) after the reconstruction. Results: A significantly higher Lysholm score was registered in Group A 90 (58-100) than in Group B 81 (38-100), P = 0.01, as well as a higher Tegner activity level 6 (2-9) versus 5 (0-9), P = 0.01. The clinical assessments revealed no significant differences between the groups in terms of the one-leg-hop test, KT-1000 arthrometer laxity measurements, manual Lachman test and range of motion (ROM). Furthermore, there was no significant difference between the groups in terms of meniscal and cartilage damage at the index operation. Conclusion: At 2 years post-operatively, patients who underwent subacute reconstruction had a significantly better outcome in terms of the Lysholm score and Tegner activity level than patients who underwent delayed reconstruction. The clinical relevance of the present study is that if the patient wishes to continue doing sports on a higher level, subacute reconstruction appears beneficial. [ABSTRACT FROM AUTHOR]

We report herein a very rare case of semitendinosus tear that formed a tumor in the popliteal region after not having recovered as a result of only being instructed to rest. The soft tissue tumor was discovered on ultrasonography 4 months after pain and sensation of discomfort appeared in the popliteal region. We considered this symptom as dependent on the presence of the tumor and selected surgical treatment. Intraoperatively, this soft tissue tumor was connected with the pes anserinus by tendinous tissue. On pathological examination, the soft tissue tumor was diagnosed as skeletal muscle showing necrosis. From imaging, operative findings, and pathological diagnosis, this was considered to represent a rare case in which myorrhexis developed into a soft tissue tumor in the popliteal region after a semitendinosus tear remained unhealed and was neglected over the long term. Although we had trouble confirming a diagnosis and treatment procedure, we were able to acquire good results with surgical treatment. This is, to the best of our knowledge, the first report of damaged semitendinosus becoming a soft tissue tumor in the popliteal region after long-term neglect without healing. [ABSTRACT FROM AUTHOR]

The complete proximal hamstring avulsion is relatively uncommon injury and predominantly occurs in young athletes but causes significant functional impairment. In chronic cases, the muscle mass is so much retracted that primary repair is not possible. A surgical technique for reconstruction of chronic proximal hamstring avulsion using contralateral semitendinosus and gracilis autograft is described in this case report.Level Of Evidence: V. [ABSTRACT FROM AUTHOR]

Background: The semitendinosus tendon has a broad and thin length of aponeurosis. Tubularizing this portion of the graft converts it into a cylindrical structure, which may have implications for graft fixation. Hypothesis: A tubularized semitendinosus tendon will demonstrate a higher tensile load to failure and increased stiffness compared with its native form. Study Design: Controlled laboratory study. Methods: Twenty cadaveric paired semitendinosus specimens were used. Ten served as the control group; the other 10 underwent tubularization along the length of the aponeurosis. All testing was performed on the MTS 858 Mini Bionix II. Outcome measures included cross-sectional area, stress, stiffness, and peak load to failure. Results: The nontubularized tendons had a higher peak tensile load to failure (mean 1112.6 ± 345.0 N) than the tubularized tendons (mean 711.4 ± 228.7 N, P 5 .007). The nontubularized specimens also had a higher stiffness (213.0 ± 37.2 N) than the tabularized group (144.9 ± 44.8 N, P = .002). Conclusion: Tubularization of the semitendinosus graft weakens its structural and mechanical properties. Clinical Relevance: On the basis of the results of this study, we do not tubularize the semitendinosus graft in ACL reconstruction because of weakened structural and mechanical properties. [ABSTRACT FROM AUTHOR]

The article presents a study which compares the use of two-stranded semitendinosus (ST) and combined ST and gracilis (STG) grafts for anterior cruciate ligament construction (ACLR). It states that the operations are performed under spinal anesthesia in which an incision is made to identify the hamstring tendons, graft preparation, and creating the tibial tunnels. It concludes that harvesting both tendons decreases deep knee flexion.

To assess the dependence on age of the expression of apoptosis regulatory proteins in the human semitendinosus muscle, we measured the expression levels of several apoptosis-related genes, including apoptosis-inducing factor (AIF), Bax, Bcl-2, caspase-3 and heat shock protein 70 (HSP70), using RT-PCR, immunohistochemistry and TUNEL assays. We found that the DNA fragmentation was proportional to the age of the tissues sample donors. The expression levels of AIF were significantly elevated (by 10 to 25%) in semitendinosus tissue samples from older individuals, but the Bax, Bcl-2, caspase-3 and HSP 70 levels remained almost constant. This data suggests that the morphological and functional changes observed in aged human semitendinosus muscle correlates with the apoptosis of muscle cells through the induction of AIF. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to compare the architectural parameters of the long head of biceps femoris (BFlh) and semitendinosus (ST) muscles by comparing measurements from ultrasound (US) with those obtained from direct dissection. The BFlh and ST architectures were examined bilaterally in 6 legs from 3 male cadavers. The fascicle length, pennation angle, muscle thickness and muscle and tendon length were obtained from direct measurement and US scans along each muscle. Intraclass correlation coefficients between the two methods ranged from 0.905 to 0.913 for the BFlh variables and from 0.774 to 0.974 for the ST parameters. Compared with the direct measurements, the US method showed a mean typical error of 0.09–0.14cm for muscle thickness, 1.01–1.31° for the pennation angle, 0.92–1.71cm for fascicle length and muscle–tendon length measurements. The US method is a valid alternative tool for assessing basic architectural parameters of ST and BFlh components of the hamstring muscles. [Copyright &y& Elsevier]

The article examines the effectiveness of electromyography (EMG)-joint torque method to determine the reliability of medial (MH) and lateral hamstring (LH) muscles during maximal voluntary isometric hamstring contractions (MVC). According to the study, full-wave-rectified and-integrated EMG has showed significant equivalent percent MVC values at all intensity levels. It found that the reliability of observing muscle contraction intensities in MH is greater than LH in gender differences. There was the linear increases in both muscles, but MH was found more reliable during low to moderate intensities.

Background: A high percentage of female athletes who sustain an anterior cruciate ligament (ACL) rupture suffer serious longterm consequences such as osteoarthritis and disability. Thus, identification of risk factors has high clinical relevance in the prevention of ACL rupture. Hypothesis: Noninjured athletes with low knee flexor electromyography (EMG) preactivity and high knee extensor EMG preactivity during sidecutting are at increased risk of future ACL rupture. Study Design: Cohort study (prognosis); Level of evidence, 2. Methods: Fifty-five elite female athletes (team handball and soccer) aged 24 ± 5 years with no history of ACL injury were tested for EMG preactivity of vastus lateralis and medialis, rectus femoris, semitendinosus, and biceps femoris during a standardized side-cutting maneuver. The incidence of ACL ruptures was registered in the following 2 match seasons. Results: During the subsequent 2 match seasons, 5 athletes sustained a confirmed noncontact ACL rupture. Before injury, all 5 players displayed a neuromuscular pattern that differed from the noninjured players, characterized by reduced EMG preactivity for the semitendinosus (ST) and elevated EMG preactivity for the vastus lateralis (VL) (P < .01). On the basis of these findings, a high-risk zone was defined as one standard deviation above the mean VL-ST difference. In our population, 5 of 10 subjects with a VL-ST difference in this zone sustained an ACL injury during the study period. Conclusion: In the present study, currently noninjured female athletes with reduced EMG preactivity of the ST and increased EMG preactivity of the VL during side cutting were at increased risk of future noncontact ACL rupture. Our data indicate that a high-risk zone can be used to identify noninjured players at high risk of future ACL rupture. Consequently, individual preventive efforts can be introduced in time. However, large prospective studies are needed to confirm this finding before definitive clinical recommendations can be made. [ABSTRACT FROM AUTHOR]

Background: Gluteus maximus strengthening exercises are employed in clinical practice as options for the treatment of low back and sacroiliac disorders. However, no studies were found that investigated which were the best exercises to activate this muscle and justify its employment in physical therapy practice. Objective: To quantify the electromyographic (EMG) activity of the gluteus maximus and semitendinosus muscles during four modalities of therapeutic exercises. Methods: Thirty-one participants (16 men, 15 women) were selected. The EMG activities of the gluteus maximus and semitendinosus was recorded and quantifi ed while the participants performed four modalities of therapeutic exercises, involving active prone hip extension in four positions: knee extension (KE), knee fl exion (KF), lateral hip rotation and knee extension (LHRKE), and lateral hip rotation and knee fl exion (LHR-KF). Results: Repeated-measures ANOVAs showed that the addition of KF or LHR increased gluteus maximus activity, whereas, KE decreased the activation of this muscle. In contrast, the exercises performed with KE increased semitendinosus activity. Conclusions: Exercises performed with KF or LHR, or a combination of the two, may be effective choices for gluteus maximus strengthening, however both KF and LHR decreased semitendinosus activity. The exercises performed with KE appeared to be an acceptable choice for semitendinosus activation. [ABSTRACT FROM AUTHOR]

Abstract: Texture parameters (peak force and compression), muscle myofibre diameter, and hydroxyproline were measured in semitendinosus samples from a cattle gene-mapping herd. The data were analysed to determine the relationships between these traits. The traits were also mapped by genetic linkage analysis to identify quantitative trait loci, and hence, candidate genes for these traits. Neither texture parameters were affected by the muscle structural traits of myofibre diameter or collagen content (as measured by hydroxyproline), despite significant variation in these traits between animals. QTL for the texture parameters of peak force and compression, as well as collagen content, were found on cattle chromosome 2 (BTA2) and attributed to the myostatin gene. Within the cattle population used for the QTL mapping, a gene variant of myostatin, F94L, has been previously shown to increase muscle mass, predominantly in the semitendinosus. It was determined herein that the F94L myostatin homozygous animals had more tender meat as measured by both peak force and compression. The variant was also responsible for a reduction in the collagen/elastin content of muscle. The myostatin F94L variant had no effect on muscle myofibre diameter of the semitendinosus, even though the variant causes substantial increases in muscle mass. Consequently, the increase in muscle mass of the variant must be due to myofibre hyperplasia and not hypertrophy. In addition, myostatin effects on tenderness are caused by changes in the extracellular matrix rather than muscle myofibre diameter. [Copyright &y& Elsevier]

Abstract: The objective of this research was to determine the difference in myofibrillar fragmentation of camel meat and beef during postmortem aging. Semitendinosus muscle was excised at slaughter and muscle pH was measured at 6, 12, 24, 48, and 72h postmortem. Myofibril fragmentation index was measured on 1, 3, 5, and 7 days postmortem. Also, myofibrils isolated from semitendinosus muscles of camel and cattle at 1, 3, 5 and 7 days postmortem storage were analyzed using sodium dodecyl sulfate (SDS)–polyacrylamide gel electrophoresis. Results showed that the camel semitendinosus muscle had significantly higher myofibril degradation values compared to that in beef which was supported by a difference in troponin-T degradation and appearance of a 30kDa band. Postmortem pH decline of camel meat was significantly slower than that of beef. This study demonstrated that the semitendinosus protease activity of camel meat was superior to that of beef, which may have been due to the difference in pH decline. [Copyright &y& Elsevier]

Abstract: The effects of gender and age on intramuscular fat (IMF) levels, cholesterol concentration, and fatty acid composition were investigated in the semitendinosus (ST) and triceps brachii (TB) muscles of feral red deer (Cervus elaphus). Six stags of >2years of age, four hinds of 1year, and six calves of 6months were shot in Slovenia. Generally, all parameters measured were influenced by interaction of muscle and treatment group (hinds, stags and calves) at the 5% level or less. In ST muscle, the IMF levels were highest for hinds. In the TB muscle, cholesterol was lower for stags than for hinds and calves. The saturated fatty acids were the highest for stags and the mono-unsaturated fatty acids for hinds. The polyunsaturated fatty acids (PUFAs) were the highest for calves and lowest for hinds. The n−3 PUFAs were the lowest for hinds. In both muscles, the calves had higher n−6 PUFAs than stags and hinds. Only the ST muscle of the hinds contained >1% (1.44%) of the conjugated linoleic acid isomer 18:2cis-9,trans-11, while in the TB of hinds and calves this fatty acid was higher than with stags. We conclude that gender and age of feral red deer influence the IMF content, the cholesterol concentration, and the fatty acid composition of the meat. [Copyright &y& Elsevier]

Copyright of Operative Orthopädie und Traumatologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hamstring injuries in sport can be debilitating. The anatomical complexity of this muscle makes uniform assessment of injury epidemiology difficult and insures that post-injury management strategies must be individually focused. This article reviews the anatomy of the hamstring, its role in athletic movement, common mechanisms of injury, and management guidelines with the goal of return into sporting activity in mind. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Biomecânica is the property of Editora Estacao Liberdade and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: We report a case of symptomatic subluxation of the semitendinosus and gracilis over the posteromedial corner of the tibia manifesting with snapping. This is the first such case recorded in non-Asian population and in a high-demand athlete. Snapping was reproduced on active extension of the knee and at initiation of flexion and could be readily palpated over the posteromedial aspect of the tibia. Dynamic ultrasound, a key diagnostic tool in such conditions, revealed abrupt anterior subluxation of the semitendinosus and gracilis tendons during active terminal extension over the insertion of the semimembranosus as well as areas of tendinopathy corresponding with the site of subluxation. Due to failure of conservative treatment, surgery was undertaken, involving tenotomy and resection of a 10–12 cm segment of the semitendinosus and gracilis. The patient returned to the same level of sporting activities within 4 months and remained symptom-free 18 months post-operatively. The role of eccentric loading of the knee joint, as well as the “protective” role of the accessory tendinous bands and aponeurotic expansions of the semitendinosus and gracilis is discussed. [Copyright &y& Elsevier]

The hamstring muscles, located in the posterior thigh, include the biceps femoris, the semimembranosus, and the semitendinosus. The proximal portions of the hamstring muscles are subject to a variety of injuries and pathology. Many of these entities affect the origin of the hamstrings, including the tendinous enthesis, the underlying ischial tuberosity, and the surrounding tissues. Tendinosis and small partial tears at the origin are the result of chronic attrition. They may be accompanied by bursitis or hamstring syndrome. Apophysitis occurs in teenagers prior to complete fusion of the ischial apophysis and results from repeated traction injuries on the apophysis without discrete displacement. Abrupt injury at the origin from forced flexion of the hip results in osseous avulsions of the apophysis in teenagers and proximal tendon ruptures in adults. Other entities affect the muscles distal to the tendon origins. These injuries include strains and partial tears of the musculotendinous junction from acute indirect trauma, delayed onset muscle soreness from overuse of the muscle group without discrete remembered injury, and contusions and myositis ossificans from direct blunt impact. The imaging features of these injuries and pathology are fairly specific and diagnostic, with the exception of some cases of myositis ossificans and chronic ischial avulsions. [ABSTRACT FROM AUTHOR]

The medial patellofemoral ligament has been recognized as the most important medial structure preventing lateral dislocation or subluxation of the patella. Numerous surgical techniques have been described to reconstruct this important structure in patients with patellofemoral instability. This paper reviews the relevant anatomy and biomechanics, published reconstruction options, and describes the surgical technique used at our institution using semitendinosus autograft to reconstruct the medial patellofemoral ligament. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to compare the results after arthroscopic anterior cruciate ligament (ACL) reconstruction using central-third bone-patellar tendon-bone (BTB) autografts and triple/quadruple semitendinosus (ST) autografts. Hypothesis: In the long-term, AOL reconstruction using BTB autografts will render more donor-site problems than ST autografts. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A randomized series of 71 patients (22 women and 49 men) with a unilateral AOL rupture who underwent reconstructive surgery were included in the study. The BTB graft was used in 34 patients (BTB group) and the ST-tendon graft was used in 37 patients (ST group). The patients were examined a median of 86 months (range, 68 to 114 months) after the reconstruction. Results: Sixty-eight of 71 patients (96%) were examined at follow-up. The clinical assessments at follow-up revealed no signif- icant differences between the BTB group and the ST group in terms of the Lyshoim score, Tegner activity level, International Knee Documentation Committee evaluation system, 1-legged hop test, KT-1 000 arthrometer laxity measurements, manual Lachman test, and range of motion. A significant improvement was seen in both groups compared with the preoperative values in terms of most clinical assessments. Donor-site morbidity in the form of knee-walking ability, kneeling ability, and area of disturbed anterior knee sensitivity revealed no significant differences between the groups. Conclusion: Seven years after AOL reconstruction, the subjective and objective outcomes were similar after using the central- third BTB autograft and triple/quadruple ST autograft. Furthermore, no difference in terms of donor-site morbidity was found between the 2 groups. [ABSTRACT FROM AUTHOR]

Copyright of Trauma und Berufskrankheit is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)