Musculotendinous Junction Research Articles

Damage to or Injury of the Distal Semitendinosus Tendon During Sporting Activities: A Systematic Review

Isolated distal semitendinosus tears and avulsions sustained during sporting activities are uncommon. We sought to systematically review the literature to identify athletes sustaining distal semitendinosus tears and avulsions during sporting activities and to better understand injury mechanisms, management, and return-to-sport timing. PubMed, Biosis Previews, SPORTDiscus, PEDro, and EMBASE databases were searched from January 1970 to January 2018 using the search terms distal hamstring, semitendinosus, sport, athlete, tear, rupture, and avulsion. Inclusion criteria were studies documenting (1) isolated, complete distal semitendinosus tears and avulsions during sporting activity, (2) injury management, and (3) athlete outcome. Exclusion criteria were studies reporting (1) partial tears, (2) injuries from non-sporting activities, or (3) athlete sustaining injury with concomitant injuries about the knee. Sporting activities, tear location, management strategy, time from injury to surgery, and return-to-sport timing were analyzed. Statistical analysis was used to evaluate return-to-sport timing based on treatment type and tear location. Four studies met the inclusion criteria, comprising a total of 23 cases of complete, isolated distal semitendinosus avulsions or tears. Injuries were sustained predominantly while running or sprinting and most commonly were avulsions off the tibia. Injuries were treated surgically in 70% of cases. Overall time to return to sport was 2.5 ± 1.4months with athletes treated conservatively returning significantly more quickly (1.5 ± 0.8months) than athletes undergoing surgery (3.0 ± 1.3months). Return-to-sport time was significantly shorter in athletes with complete avulsions (2.2 ± 1.3 months) than in those sustaining tears at the musculotendinous junction (3.8 ± 0.8months). No significant correlation between time to surgery and return-to-sport time was appreciated. Isolated, complete distal semitendinosus tears and avulsions remain infrequently reported during sporting activities and, in this review, occurred predominantly during non-contact activity. Athletes treated conservatively were found to return to sport more quickly, although additional studies are needed to determine the clinical relevance of treatment option, tear location, and concurrent injuries.

Rotator Cuff Tear Morphologic Parameters at Magnetic Resonance Imaging: Relationship With Muscle Atrophy and Fatty Infiltration and Patient-Reported Function and Health-Related Quality of Life.

The aim of this study was to determine the relationship between rotator cuff tear (RCT) morphologic parameters and muscle atrophy and fatty infiltration, and patient-reported outcome measures, in patients with symptomatic full-thickness RCT. Rotator cuff tear location, length, width, thickness, and musculotendinous junction position were assessed in 57 magnetic resonance imaging scans and correlated to the outcome measures using multivariate regression analysis. Supraspinatus tendon tear length (odds ratio [OR], 2.218; 95% confidence interval [CI], 1.460-3.370), supraspinatus musculotendinous junction position (OR, 2.037; 95% CI, 1.322-3.137), and infraspinatus tendon tear width (OR, 2.371; 95% CI, 1.218-4.615) were identified as the strongest determinants of supraspinatus muscle atrophy, supraspinatus muscle fatty infiltration, and infraspinatus muscle fatty infiltration, respectively. The extent of supraspinatus tendon and musculotendinous junction retraction influences the development of supraspinatus muscle atrophy and fatty infiltration, whereas the extent of infraspinatus tendon tear width influences the development of infraspinatus muscle fatty infiltration. Morphologic parameters defining RCT at magnetic resonance imaging did not correlate with clinical shoulder function scores.

Non-Operative Rehabilitation of Isolated Popliteus Tendon Rupture in a Rugby Player

Isolated rupture of the popliteus tendon is uncommon; instead, it is often seen as part of multi-ligamentous posterolateral corner injuries. In this report, we present a case of a 22-year-old professional rugby player who sustained a lateral blow to his semi-flexed knee in a tackle during a competitive game. A complete popliteus tendon rupture at its musculo-tendinous junction was diagnosed on magnetic resonance imaging despite a relatively unremarkable physical examination. The aims of this report are to highlight the diagnostic challenges with this rare injury as physical signs are often subtle and non-specific. Furthermore, we demonstrate the viability of conservative management in the setting of a direct contact mechanism. Indeed, our patient was successfully treated with a specific rehabilitation protocol via isometric quadriceps contractions, gastrocnemius-soleus and hamstring strengthening exercises and graded activity with successful return to full contact activities at 4 weeks and regular season matches shortly after.

Bilateral extraocular muscle enlargement and proptosis associated with squamous cell carcinoma of the lung.

Thyroid-associated orbitopathy is characterised on cross-sectional imaging by symmetric extraocular muscle enlargement sparing the musculotendinous junction. We report a case of this imaging finding in a biochemically euthyroid patient with metastatic squamous cell carcinoma of the lung undiagnosed at time of presentation.

Treatment of an invasive equine mast cell tumour in the extensor carpi radialis by extensive tenomyectomy and local corticosteroid injections

SummaryEquine mast cell tumours (MCT) have been reported to occur in the skin, respiratory tract, oral cavity, synovial structures and eye. These tumours are typically locally invasive and nonaggressive. In this case, a MCT was located in the extensor carpi radialis (ECR) and was highly infiltrative. Excision of the ECR and local corticosteroid injection was curative and resulted in a good functional outcome. A 12‐year‐old Thoroughbred gelding presented for lameness, swelling and pruritus associated with the right antebrachium. Sonographic changes were suggestive of severe tenosynovitis and purulent material in the ECR. Surgical exploration revealed maceration at the ECR musculotendinous junction. The extensor sheath contained a large quantity of caseous material and serosanguinous fluid. The ECR tendon and 75% of the muscle was excised. Cytology and histopathology were consistent with a MCT that infiltrated the surgical margins. Post‐operatively the horse was treated with multiple local corticosteroid injections along the incision. Right forelimb movement was initially limited, however, there was steady improvement over 3 months with increasing exercise. At 18 months post‐operatively, no lameness was detectable in the walk, trot or canter and no recurrence of MCT was apparent. The horse appeared to compensate for loss of the ECR by using the biceps during the swing phase. Partial excision and local corticosteroid treatment can be curative for cases of invasive MCT. Extensive excision of the ECR is a viable treatment option for neoplasia or other conditions affecting the ECR in the horse.

Posterolateral Rotatory Knee Instability-MRI Evaluation of Anatomic Landmarks for Tibial Drill Tunnel Placement in Open and Arthroscopic Popliteus Tendon Reconstruction.

Anatomic reconstruction of the popliteus tendon and arcuate complex results in superior functional and a biomechanically more stable outcome compared with extra-anatomic techniques in posterolateral rotatory knee instability. Although specific characteristics of the femoral and fibular footprint of the anatomic posterolateral reconstruction have been described, data for tibial tunnel placement while popliteus tendon reconstruction do not exist. The purpose of this study was to quantify reasonable parameters, which could be used in arthroscopy, fluoroscopy, or open surgery to determine the anatomic tibial drill tunnel position in popliteus tendon reconstruction. Thirty magnetic resonance images of 30 patients with an intact posterolateral corner (PLC) were analyzed to specify the ideal point for tibial fixation of a popliteus tendon graft with respect to 17 bony, cartilaginous, and ligamentous anatomic landmarks. The ideal point for tibial fixation was defined as the musculotendinous junction of the popliteus tendon near to the insertion of the popliteofibular ligament. In the coronal plane, the ideal tibial fixation was located at the crossing of a tangent to the fibular head, parallel to the joint line with a tangent to the medial border of the fibular head, and vertical to the joint line with a deviation of less than 1 mm. It was located 0.26 (±1.91) mm superior to the distal edge and 11.75 (±2.66) mm lateral to the lateral edge of the tibial posterior cruciate ligament footprint and only 8.68 (±2.81) mm lateral to the lateral edge of the neurovascular bundle. Interrater reliability to detect the correct position of the popliteus tendon graft footprint was almost perfect. The position for tibial drill tunnel placement in anatomic popliteus tendon reconstruction showed low interindividual differences. The present findings of the quantified anatomic landmarks might improve open, fluoroscopy, or arthroscopy guided PLC reconstruction.

Biomechanical Comparison of Open and Endoscopic Proximal Hamstring Repair Techniques

Objectives:Proximal hamstring tendon avulsions are a rare subset of hamstring injuries, and surgical fixation has become standard, given superior outcomes compared to nonoperative treatment. Open surgical techniques employ a large incision near the gluteal crease and necessitate extensive retraction for optimal visualization, which may increase risk for infection, numbness and potential sciatic nerve injury. Recently described endoscopic repair techniques enable optimal visualization and access to the tendon and ischial tuberosity through several small incisions, potentially reducing risks associated with open repair. Prior cadaveric studies have evaluated biomechanical properties of open repair techniques. The purpose of this study was to compare the biomechanical properties of open and endoscopic suture anchor repair of proximal hamstring ruptures to validate the structural integrity of the endoscopic technique.Methods:Nine fresh-frozen cadaver pelvises (5 M, 4F) were randomly assigned open proximal hamstring repair, with subsequent contralateral endoscopic proximal hamstring repair. Laterality was evenly distributed. Open repair was performed after reflection of the gluteus maximus to optimize visualization and anchor placement during repair, while endoscopic repair was performed via four small incisions surrounding the ischial tuberosity. Proximal hamstring ruptures were simulated by subperiosteal dissection of the entire tendon from its insertion. Repairs were performed using two double-loaded 3.0 mm polyether ether ketone (PEEK) suture anchors and two 3.75 mm PEEK knotless screw-in anchors in a double-row configuration. After repair, the ischial tuberosity was harvested by cutting the inferior pubic ramus and superior aspect of the ischial tuberosity as far away from the repair site as possible. The bony inferior ramus and ischial tuberosity was potted into an acrylic cylinder using polymethylmethacrylate, while the musculotendinous junction was wrapped in gauze and clamped 3 cm from the insertion. Reference lines were marked at the insertion site and 1, 2, and 3 cm from the insertion to aid optical measurements. Potted specimens were mounted into an MTS 858 MiniBionix servohydraulic test frame and tested according to a previously established protocol. Each specimen was cycled 50 times within a pre-established range, with the range increased every 50 cycles until failure. Values were then compared using a paired t-test.Results:The open repair group failed at a mean of 119 cycles with an average displacement of 12.7 mm at a mean ultimate load of 574.5 N. The endoscopic repair group failed at a mean of 117 cycles with an average displacement of 14.9 mm at and mean ultimate load of 563.4 N. No statistically significant difference was noted among any of these parameters.Conclusion:This biomechanical analysis demonstrated no difference in the structural properties comparing open and endoscopic techniques. Endoscopic proximal hamstring repair is a viable option for surgical fixation of proximal hamstring avulsions, with the potential to decrease risks encountered using open techniques.

Anatomical Feasibility Study of Flexor Hallucis Longus Transfer in Treatment of Achilles Tendon and Posterior Ankle Arthroscopy

Category: Hindfoot Introduction/Purpose: The aim of this study was to evaluate the occurrence of anatomical variations of the musculotendinous junction of the flexor hallucis longus (FHL) muscle, the relationship between FHL tendon or muscle and the tibial neurovascular bundle at the level of the posterior ankle joint in human cadavers. Methods: Seventy embalmed feet from 20 male and 15female cadavers, the cadavers’ mean age was 65.4 (range from 14 to 82) years, were dissected and anatomically classified to observe FHL muscle morphology define the relationship between FHL tendon or muscle and the tibial neurovascular bundle . The distance between the musculotendinous junction and thehe relationship between FHL tendon or muscle and the tibial neurovascular bundle was determined. Results: The three morphology types of FHL muscle were identified: a long lateral and shorter medial muscle belly, which was observed in 63 specimens (90%).; equal length medial and lateral muscle bellies, this variant was only observed in 5 specimens (7.1%); a lateral and no medial muscle belly, which was observed in 2 specimens (2.9%). No statistically significant difference was observed according to gender or side (p > 0.05). Two patterns were identified and described between FHL tendon or muscle and the tibial neurovascular bundle. Pattern 1, the distance between the neurovascular bundle and FHL tendon was 3.46 mm (range, 2.34 to 8.84, SD = 2.12) which was observed in 66 specimens (94.3%); Pattern 2, there was no distance which was observed in 4 specimens (5.7%). Conclusion: Knowing FHL muscle morphology variations provide new important insights into secure planning and execution of a FHL transfer for Achilles tendon defect as well as for the interpretation of ultrasound and magnetic resonance images. During posterior arthroscopic, posteriormedial portal may be introduced into the posterior aspect of the ankle without gross injury to the tibial neurovascular structures.

Isolated Tearing and Avulsion of the Distal Biceps Femoris Tendon During Sporting Activities: A Systematic Review.

Background:Isolated tearing and avulsions of the distal biceps femoris sustained during sporting activities are uncommon.Purpose:To systematically review the literature to identify distal biceps femoris tears and avulsions experienced during sporting activities to determine injury prevalence, sporting activities/mechanisms, management, and time to return to sport.Study Design:Systematic review; Level of evidence, 4.Methods:A systematic review was conducted investigating studies published between January 1970 and December 2017 that reported on athletes sustaining tears and avulsions of the distal biceps femoris during sporting activity. The review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and used the PubMed, Biosis Previews, SPORTDiscus, PEDro, and EMBASE databases. Inclusion criteria were studies reporting on (1) partial or complete tears and avulsions of the distal biceps femoris with documented sporting activity causing injury, (2) injury management (operative vs nonoperative), and (3) patient outcome. Exclusion criteria consisted of studies reporting on (1) distal biceps femoris injuries without tearing, (2) injuries secondary to nonsporting activities (mechanical falls, trauma), (3) concomitant injuries to adjacent structures about the knee, and (4) studies not reporting injury management or patient outcomes. Sporting activities, injury characteristics, management, and time to return to sport were analyzed.Results:A total of 22 athletes with isolated distal biceps femoris tears or avulsions were identified. Injuries were predominantly associated with noncontact knee hyperextension with concurrent hip flexion during soccer or track and field, most commonly isolated to the musculotendinous junction. Injuries were treated surgically in 91% (20/22) of athletes. Mean (±SD) overall time to return to sport was 4.9 ± 3.3 months, and for athletes who underwent operative repair, there were no significant postoperative differences based on injury location (musculotendinous junction vs avulsion, P = .25) or injury severity (partial vs complete injury, P = .13).Conclusion:Isolated distal biceps femoris injuries occurred primarily via noncontact mechanisms. The majority of cases were treated surgically, with successful return to sport at preinjury levels. No significant difference in return to sport was appreciated based on injury location or severity. Further studies are necessary to determine the impact of treatment method.

Difference in medial gastrocnemius mechanical properties between paretic and non-paretic legs in children with unilateral cerebral palsy

Children with spastic unilateral cerebral palsy (CP) present very early in childhood alterations in gastrocnemius muscle structural and mechanical properties that can be non-invasively investigated through 2D ultrasonography (US). To gain knowledge about spastic muscle properties during ankle mobilization, the purpose of this study was to assess gastrocnemius medialis (GM) muscle passive stiffness and strain during ankle mobilization in both paretic and non-paretic legs in children with unilateral CP. Thirteen children (6- to 12-year-old) with unilateral spastic CP, participated in two sessions of measurements with a one-week interval. Children were installed prone on an isokinetic dynamometer while their ankle was passively mobilized from 25° plantarflexion to maximal dorsiflexion at 2°/s. EMG activity was monitored to ensure complete relaxation. Displacement of the musculo-tendinous junction (MTJ) was recorded with US during mobilization and was synchonized with passive torque. GM stiffness was then calculated as the slope of the torque/MTJ displacement relationship. GM strain was calculated as the GM excursion divided by GM resting length (measured at neutral position with simple US tape method). Inter-session reliability was assessed with the measurement of coefficient of variation (CV) between both experimental sessions. GM stiffness was higher for the paretic leg than for the non-paretic one (4.2 vs. 3 Nm/cm; P = 0.025). When considered on the same angular range (i.e. −25° plantarflexion to maximal dorsiflexion angle on paretic leg), GM strain was similar between both legs ( P = 0.43). Inter-session reliability of GM stiffness (9.75% ≤ CV ≤ 10.67%), strain (CV ≤ 9.97%) and length (CV ≤ 7.5%) were good. Spastic GM muscle lengthening during ankle mobilization was characterized by an increased stretch resistance when compared to non-paretic muscle despite similar passive GM strain between both legs. This may be due to altered spastic GM growth during childhood, characterized by reduced GM paretic length.

Difference in medial gastrocnemius mechanical properties between paretic and non-paretic legs in children with unilateral cerebral palsy

Children with spastic unilateral cerebral palsy (CP) present very early in childhood alterations in gastrocnemius muscle structural and mechanical properties that can be non-invasively investigated through 2D ultrasonography (US). To gain knowledge about spastic muscle properties during ankle mobilization, the purpose of this study was to assess gastrocnemius medialis (GM) muscle passive stiffness and strain during ankle mobilization in both paretic and non-paretic legs in children with unilateral CP. Thirteen children (6- to 12-year-old) with unilateral spastic CP, participated in two sessions of measurements with a one-week interval. Children were installed prone on an isokinetic dynamometer while their ankle was passively mobilized from 25° plantarflexion to maximal dorsiflexion at 2°/s. EMG activity was monitored to ensure complete relaxation. Displacement of the musculo-tendinous junction (MTJ) was recorded with US during mobilization and was synchonized with passive torque. GM stiffness was then calculated as the slope of the torque/MTJ displacement relationship. GM strain was calculated as the GM excursion divided by GM resting length (measured at neutral position with simple US tape method). Inter-session reliability was assessed with the measurement of coefficient of variation (CV) between both experimental sessions. GM stiffness was higher for the paretic leg than for the non-paretic one (4.2 vs. 3 Nm/cm; P = 0.025). When considered on the same angular range (i.e. −25° plantarflexion to maximal dorsiflexion angle on paretic leg), GM strain was similar between both legs ( P = 0.43). Inter-session reliability of GM stiffness (9.75% ≤ CV ≤ 10.67%), strain (CV ≤ 9.97%) and length (CV ≤ 7.5%) were good. Spastic GM muscle lengthening during ankle mobilization was characterized by an increased stretch resistance when compared to non-paretic muscle despite similar passive GM strain between both legs. This may be due to altered spastic GM growth during childhood, characterized by reduced GM paretic length.

Endoscopic Proximal Hamstring Repair: Portal Site Anatomy - A Cadaveric Study

Objectives:Hamstring injuries commonly cause pain, weakness and functional limitations. While most hamstring injuries involve the musculotendinous junction or muscle belly, proximal hamstring tendon avulsions are a subset of hamstring injuries that are frequently more debilitating. Nonoperative treatment has demonstrated poor outcomes, thus surgical repair has become the mainstay. Open surgical repair has been the standard, but improved endoscopic techniques have enabled proximal hamstring fixation with decreased risk of infection and numbness, without the morbidity of a large, posterior incision. Prior anatomic studies described relevant anatomy near the proximal hamstring origin at the ischial tuberosity in the setting of an open repair, but literature describing pertinent anatomy during endoscopic repair is sparse. This cadaveric study enhances knowledge and safety of endoscopic proximal hamstring repair by describing pertinent anatomy surrounding four commonly used endoscopic portals.Methods:Ten fresh-frozen pelvis specimens (5 M, 5F) underwent endoscopic proximal hamstring repair and dissection with evenly distributed laterality (5 R, 5 L). Proximal hamstring ruptures were simulated endoscopically with an arthroscopic knife. Endoscopic repair was then completed on each specimen through four endoscopic portals (Inferolateral, Medial, Superolateral and Accessory Superior) using two double-loaded 3.0 mm polyether ether ketone (PEEK) suture anchors and two 3.75 mm PEEK knotless screw-in anchors. After repair, portal tracts were maintained by inserting four 2.0 mm k-wires through cannulas placed through the portals, securing the wires in bone in the ischial tuberosity beyond the zone of repair. The specimen was dissected in layers around the wires, and measurements from portal tracts to nine pertinent anatomic structures were obtained using a digital caliper. Each measurement was repeated three times, then averaged to obtain a composite mean. Measurements were statistically verified with an intraclass correlation coefficient (ICC), all but two of which were above 0.90.Results:Ten cadaveric specimens demonstrated a mean age and BMI of 45.4 and 27.3, respectively. With respect to anatomic measurements, on average no portal tract was closer than 2.0 cm to the sciatic nerve, inferior gluteal neurovascular bundle or posterior cutaneous nerve, and all double-row repairs were easily completed with good fixation through these four portals (Table 1). Additional anatomic landmarks surrounding the hamstring origin were identified endoscopically, and when routinely located, each landmark helped improve reproducibility and safety of endoscopic proximal hamstring repair (Figure 1).Conclusion:This cadaveric study of the proximal hamstring origin maps the anatomic landscape encountered endoscopically, and supports the efficacy and safety of endoscopic proximal hamstring repair.Average distances (cm) from endoscopic portal sites to nine anatomic structures.InferolateralMedialSuperolateralAccessory SuperiorInferior Border Gluteus Maximus2.491.574.153.95Adductor Magnus0.690.881.802.95Conjoint Hamstring Tendon0.801.250.601.27Tip of Ischial Tuberosity1.151.272.363.39Sacrotuberous Ligament2.592.231.811.04Sciatic Nerve2.913.972.373.04Short External Rotators3.413.461.891.25Posterior Cutaneous Nerve3.344.542.553.22Inferior Gluteal Neurovascular Bundle5.825.964.273.65Figure 1.Endoscopic view of a left hip from the medial portal. The intact hamstring tendon is in the center of the image, with pertinent surrounding anatomy. 1. The sacrotuberous ligament. 2. The adductor magnus tendon and muscle fibers. 3. The lateral edge of the ischial tuberosity (with the fibers of the quadratus femoris just lateral to it). 4. The inferior fibers of the inferior gemellus muscle.

Acute Pectoralis Major Tears in Forward Deployed Active Duty U.S. Military Personnel: A Population at Risk?

The purpose of this study is to report on the causes of a series of acute pectoralis major tears in active duty deployed military personnel. Nine cases of acute pectoralis major tears evaluated at one expeditionary military treatment facility over a 4-month deployment cycle were analyzed. Nine male patients were diagnosed with tears: seven complete tears at the tendinous insertion, one complete tear at the musculotendinous junction, and one incomplete tear, with a mean age of 32 years (range, 23-52 years). All injuries occurred during bench press, with the dominant upper extremity involved 56% of the time. Injury occurred an average of 77 days into the tour (range, 3-198 days). Mean time from injury to surgical repair in the cohort was 18 days (range, 10-43 days). Combat-deployed active duty U.S. military personnel likely represent a high-risk population for this injury. Surgical repair is possible, but rarely advisable, in the deployed setting. (Journal of Surgical Orthopaedic Advances 28(2):150-157, 2019).

Estimating Lengths of Semitendinosus and Gracilis Tendons by Magnetic Resonance Imaging

To determine whether preoperative magnetic resonance imaging (MRI) can help predict the tendon-only length of the semitendinosus (ST) and the gracilis (G). The distance from the tibial insertion to the distal-most aspect of the musculotendinous junction (MTJ) of the ST and G was estimated on preoperative MRI scans of patients undergoing primary anterior cruciate ligament (ACL) reconstruction with single-bundle, quadruple-stranded hamstring autograft. This MRI tendon-only length, measured by a musculoskeletal radiologist blinded to surgical findings, was compared to the actual tendon-only length measured upon harvesting each tendon. Among the 42 patients comprising the study population, there was very strong correlation between the estimates of tendon-only length made by MRI and surgical measurements for both the ST (Spearman coefficient= 0.83; P < .0001) and the G (Spearman coefficient= 0.82; P < .0001). The difference between MRI and surgical measurements did not exceed 3cm for any of the 84 harvested hamstring tendons. Bland-Altman plots confirmed agreement between the 2 measurement methods. There was also strong correlation between the surgically measured tendon-only length of the ST and its G counterpart (Spearman coefficient= 0.68; P < .0001). MRI estimates of tendon-only length for both the ST and G very strongly correlate with operative measurements of these lengths; the discrepancy between these 2 measurement methods was found to not exceed 3cm when the MTJ of these tendons is visible on MRI scans. Level III, comparative study.

Anatomical feasibility study of flexor hallucis longus transfer in treatment of Achilles tendon and posteromedial portal of ankle arthroscopy

The aim of this study was to evaluate the occurrence of anatomical variations of the musculotendinous junction of the flexor hallucis longus (FHL) muscle, the relationship between FHL tendon or muscle and the tibial neurovascular bundle at the level of the posterior ankle joint in human cadavers. Seventy embalmed feet from 20 male and 15 female cadavers, the cadavers' mean age was 65.4 (range from 14 to 82)years, were dissected and anatomically classified to observe FHL muscle morphology define the relationship between FHL tendon or muscle and the tibial neurovascular bundle. The distance between the musculotendinous junction and the relationship between FHL tendon or muscle and the tibial neurovascular bundle was determined. Three morphology types of FHL muscle were identified: a long lateral and shorter medial muscle belly, which was observed in 63 specimens (90%); equal length medial and lateral muscle bellies, this variant was only observed in five specimens (7.1%); one lateral and no medial muscle belly, which was observed in two specimens (2.9%). No statistically significant difference was observed according to gender or side (p > 0.05). Two patterns were identified and described between FHL tendon or muscle and the tibial neurovascular bundle. Pattern 1, the distance between the neurovascular bundle and FHL tendon was 3.46mm (range 2.34-8.84, SD = 2.12) which was observed in 66 specimens (94.3%); Pattern 2, there was no distance which was observed in four specimens (5.7%). Knowing FHL muscle morphology, variations provide new important insights into secure planning and execution of a FHL transfer for Achilles tendon defect as well as for the interpretation of ultrasound and magnetic resonance images. With posterior arthroscopic for the treatment of various ankle pathologies, posteromedial portal may be introduced into the posterior aspect of the ankle without gross injury to the tibial neurovascular structures because of the gap between the neurovascular bundle and FHL tendon.

Factors Predictive of Healing in Large Rotator Cuff Tears: Is It Possible to Predict Retear Preoperatively?

Background: Many studies have identified risk factors that cause retear after rotator cuff repair. However, it is still questionable whether retears can be predicted preoperatively. Purpose: To determine the risk factors related to retear after arthroscopic rotator cuff repair and to evaluate whether it is possible to predict the occurrence of retear preoperatively. Study Design: Case-control study; Level of evidence, 3. Methods: This study enrolled 112 patients who underwent arthroscopic rotator cuff repair with single-row technique for a large-sized tear, defined as a tear with a mediolateral length of 3 to 5 cm. All patients underwent routine magnetic resonance imaging (MRI) at 9 months postoperatively to assess tendon integrity. The sample included 61 patients (54.5%) in the healed group and 51 (45.5%) in the retear group. Results: In multivariate analysis, the independent predictors of retears were supraspinatus muscle atrophy (P < .001) and fatty infiltration of the infraspinatus (P = .027), which could be preoperatively measured by MRI. A significant difference was found between the two groups in sex, the acromiohumeral interval, tendon tension, and preoperative or intraoperative mediolateral tear length and musculotendinous junction position in univariate analysis. However, these variables were not independent predictors in multivariate analysis. The cutoff values of occupation ratio of supraspinatus and fatty infiltration of the infraspinatus were 43% and grade 2, respectively. The occupation ratio of supraspinatus <43% and grade ≥2 fatty infiltration of the infraspinatus were the strongest predictors of retear, with an area under the curve of 0.908, sensitivity of 98.0%, and specificity of 83.6% (accuracy = 90.2%). Conclusion: In patients with large rotator cuff tears, it was possible to predict the retear before rotator cuff repair regardless of intraoperative factors. The retear could be predicted most effectively when the occupation ratio of supraspinatus was <43% or the fatty infiltration of infraspinatus was grade ≥2. Predicting retear preoperatively may help surgeons determine proper treatment and predict the postoperative prognosis.

India: PolyOne – plastic colorants

Medial row sutures placed at the musculotendinous junction are more likely to cut through the tendon than those sutures placed 10 mm lateral to the junction. Even if there is little tendon left, putting the stitches at the junction is a bad idea. In this instance, a single-row repair is better.

Could immediate treatment change the management method of digital tendon musculotendinous junction avulsion?: a systematic review

Could immediate treatment change the management method of digital tendon musculotendinous junction avulsion?: a systematic review

Factors affecting rotator cuff integrity after arthroscopic repair for medium-sized or larger cuff tears: a retrospective cohort study

We wished to identify the preoperative prognostic factors associated with structural integrity after repair of medium-sized and larger rotator cuff tears and to determine the cutoff values using receiver operating characteristic curve analysis. The study included 180 patients with medium-sized and larger rotator cuff tears. Each had a minimum 2-year postoperative follow-up by magnetic resonance imaging. We assessed several patient-related and disease-related preoperative factors using univariate and multivariate logistic regression analysis. To determine the cutoff value for the significant variables, receiver operating characteristic curve analysis was performed. Retears occurred in 28 of the 180 patients (15.6%). Univariate analysis found that retear was significantly affected by the type of work and pattern of tear. The rate of retear was significantly increased in diabetes and with increasing tear size, extent of retraction, delamination, and fatty infiltration. Furthermore, reduced remnant tendon length, distance from the musculotendinous junction to the face of the glenoid, occupation ratio, and acromiohumeral interval were also significant risk factors. In the multivariate analysis, body mass index, diabetes, dyslipidemia, extent of retraction, delamination, distance from musculotendinous junction to face of glenoid, occupation ratio, fatty infiltration of infraspinatus, and acromiohumeral interval remained significant risk factors. The extent of retraction (22.2 mm) and the occupation ratio (53.5%) showed highly accurate cutoff values for predicting retear. Multiple factors influenced the healing process after rotator cuff repair. The best predictors were the extent of retraction and occupation ratio, which could help assist in determining the prognosis after rotator cuff repairs.

Lacertus Fibrosus Versus Achilles Allograft Reconstruction for Distal Biceps Tears: A Biomechanical Study

Background: The bicipital aponeurosis, or lacertus fibrosus, can potentially be used as a reconstruction graft in chronic distal biceps tendon tears. Purpose: To evaluate construct stiffness, load to failure, and failure mechanism with lacertus fibrosus versus Achilles allograft for distal biceps tendon reconstruction. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen matched cadaveric pairs of elbows were used. Three centimeters of the distal biceps tendon was resected. Specimens were randomized to the lacertus fibrosus or Achilles tendon group. In one group, the lacertus fibrosus was released from its distal attachment and then tubularized and repaired intraosseously to the radius. In the other group, an Achilles tendon graft was sutured to the biceps muscle and repaired to the ulna. The prepared radii were rigidly mounted at a 45° angle on a load frame. The proximal biceps muscle was secured in a custom-fabricated cryogenic grip. Displacement was measured using a differential variable reluctance transducer mounted at the radius–soft tissue junction and in the muscle- or muscle allograft–tissue junction proximal to the repair. Specimens were loaded at 20 mm/min until failure, defined as a 3-mm displacement at the radius–soft tissue junction. Results: No significant difference was found in mean load to failure between the lacertus fibrosus and Achilles tendon group (mean ± SD, 20.2 ± 5.5 N vs 16.89 ± 4.54 N; P = .18). Stiffness also did not differ significantly between the lacertus fibrosus and Achilles tendon group (12.3 ± 7.1 kPa vs 10.5 ± 5.7 kPa; P = .34). The primary mode of failure in the lacertus fibrosus group was suture pullout from the tissue at the musculotendinous junction (7 of 10). In the Achilles group, failures were observed at the muscle-allograft interface (3) and the allograft-bone (radial tuberosity) interface (3), and 3 suture failures were observed. The button fixation did not fail in any specimens. Conclusion: The mean stiffness and load-to-failure values were not significantly different between a lacertus fibrosus construct and Achilles tendon allograft. Clinical Relevance: Use of the lacertus fibrosus may be a potential alternative to Achilles tendon allograft reconstruction of chronic distal biceps tears when primary repair is not possible.