A Successful Arthroscopic Management of a Benign but Locally Aggressive Tenosynovial Giant Cell Tumour in the Shoulder.

Introduction Pigmented villonodular synovitis (PVNS) is a relatively rare disorder affecting the synovial membrane and tendon sheath of a joint. It rarely affects the shoulder joint. This prospective study aims to document the challenges encountered in achieving total synovectomy and assesses the clinical outcomes of arthroscopic synovectomy for PVNS in shoulder patients. Methods This is a prospective study conducted from April 2017 to September 2023. This monoarticular disease was observed among six patients (four females and two males). All patients underwent arthroscopic extensile synovectomy with biopsy and culture. The outcomes were measured using Constant score, American Shoulder and Elbow Surgeons (ASES), and University of California Los Angeles (UCLA) scores. All patients were followed up for a minimum of 36 months after arthroscopic synovectomy. Results All intraoperative findings were consistent with PVNS and confirmed with histopathological examination. All patients achieved a satisfactory, painless range of movements following surgery. The individual Constant score improved from a mean value of 64.83 to 94.50, the ASES score improved from a mean value of 81.15 to 99.73, and the UCLA score improved from a mean value of 23.16 to 34.83 post-arthroscopic intervention, proving its effectiveness. No recurrences were reported after 36 months of follow-up. Conclusion PVNS can be easily missed, and one must have a high index of suspicion to diagnose early. Delayed presentation of the disease had led to severe destruction of the joint. Early diagnosis and arthroscopic intervention prior to joint destruction are crucial for achieving a good functional outcome. Incomplete excision may lead to recurrence of the disease. Therefore, we propose extensile arthroscopic synovectomy of the shoulder, wherein by expecting and addressing the intraoperative challenges, complete excision can be achieved, thus preventing recurrence.

Unprecedented Multifunctionality in Novel Monophase Micro/Nanostructured Ti-Zn Alloy.

It is always challenging to integrate multiple functions into one material system. However, those materials/devices will address society's critical global challenges and technological demands if achieved with innovative design strategies and engineering. Here, one such material with a broader spectrum of desired properties appropriate for seven applications is identified and explored, and a glucose-sensing-triggered energy-storage mechanism is demonstrated. To date, the Titanium (Ti)-Zinc (Zn) binary alloys are investigated only as mixed phases and for a maximum of three applications. In contrast, the novel single phase of structurally stable 50 Ti-50 Zn (Ti0.5 Zn0.5 ) is synthesized and proven suitable for seven emerging applications. Interestingly, it is thermally stable up to 750 °C and possesses excellent mechanical, tribological properties and corrosion resistance. While exceptional biocompatibility is evident even up to a concentration of 500 µg mL-1 , the antibacterial activity against E. coli is also seen. Further, rapid detection and superior selectivity for glucose, along with supercabattery behavior, unambiguously demonstrate that this novel monophase is a remarkable multifunctional material than the existing mixed-phase Ti-Zn compounds. The coin-cell supercapacitor shows outstanding stability up to 30 000 cycles with >100% retention capacity. This allows us to prototype a glucose-sensing-triggered energy-storage-device system for wearable point-of-care diagnostic applications.

Enhancement in Thermoelectric Performance in Ti-doped Yb0.4Co4Sb12 Skutterudites via Carrier Optimization and Phonon Anharmonicity.

Yb0.4Co4Sb12, being a well-studied system, has shown notably high thermoelectric performance due to the Yb filler atom-driven large concentration of charge carriers and lower value of thermal conductivity. In this work, the thermoelectric performance of YbzCo4-xTixSb12 (where z = 0, x = 0 and z = 0.4, x = 0, 0.04, and 0.08) upon Ti doping prepared by the melt-quenched-annealing followed by spark plasma sintering (SPS) has been studied in the temperature range of 300-700 K. Addition of Yb and doping of donor Ti at the Co site simultaneously increase the electrical conductivity to 1453.5 S/cm at 300 K, which ultimately boosts the power factor as high as ∼4.3 mW/(m·K2) at 675 K in Yb0.4Co3.96Ti0.04Sb12. Adversely, a significant reduction in thermal conductivity is obtained from ∼7.69 W/(m·K) (Co4Sb12) to ∼3.50 W/(m·K) (Yb0.4Co3.96Ti0.04Sb12) at ∼300 K. As a result, the maximum zT is achieved as ∼0.85 at 623 K with high hardness of 584 HV for the composition of Yb0.4Co3.96Ti0.04Sb12, which demonstrates it to be an efficient material suitable for intermediate temperature thermoelectric applications.

Lumbar Spine Injury in Indian Fast Bowlers: 3D Biomechanical Analysis and Prevention Strategies.

Background: Lumbar spine injuries are among the most common overuse injuries in a fast bowler. Among various causative factors, bowling action technique is a crucial one. Three-dimensional motion analysis has been accepted as a gold standard tool to identify incorrect techniques. Previous studies have identified key biomechanical variables associated with lumbar injury risk in fast bowlers. Despite the large popularity of the sport, there is limited information available on the subject in Indian fast bowlers. This study aims to analyse the lumbar spine injury risk in Indian fast bowlers with respect to key biomechanical variables, using 3D motion analysis. Methods: Forty-seven male first class fast bowlers underwent 3D motion analysis in an indoor biomechanics laboratory. Motion capture was done with 3D cameras and 2D video cameras, using a standard marker set. Data processing and analysis was done using proprietary software. Biomechanical variables associated with lumbar spine injury risk including lateral trunk flexion (LTF) and knee angle at front foot contact (KA at FFC) were measured, and peak vertical ground reaction forces (pVGRF) were simultaneously recorded using force plates. Descriptive analysis of the data was done. Results: 26% of bowlers had a high LTF, 29% had low KA at FFC and 43% had high pVGRF. Thus, a large proportion of bowlers in this study were at risk of lumbar spine injury with respect to the assessed variables. Conclusion: This highlights the role of 3D motion analysis in early identification of injurious techniques, which can be modified by coaching and training interventions to prevent injuries. This study thus has implications on coaching and training of fast bowlers in India.

Preoperative Templating of Bone-Patellar Tendon-Bone Graft for Anterior Cruciate Ligament Reconstruction: A Morphometry-Based Graft Harvest Method

Background@#Knowledge of anatomy and morphometry of the patella and patellar tendon is crucial for the selection of bonepatellar tendon-bone (BTB) graft for anterior cruciate ligament reconstruction. Graft tunnel mismatch in BTB graft especially in patients with patella alta or baja can result in compromised fixation for the bone-to-bone healing. This complication can be avoided by proper templating of graft using parameters measured from magnetic resonance imaging (MRI). The study aimed to derive morphometric data from MRI and predict the suitability of BTB graft preoperatively. @*Methods@#MRI of 1,002 knees was chosen from database after applying the eligibility criteria, which included individuals in the age group of 18–50 years (both sexes) with the intact patella and patellar tendon. Individuals with pathologies of the knee joint and associated structures such as patellar fracture/dislocations, fractures of the distal femur and proximal tibia, and avulsion of the quadriceps tendon or patellar tendon were excluded. For analysis, 1.5 Tesla, proton density, and fat-suppressed sequences of sagittal and axial sections of T2-weighted MRI images were used. @*Results@#Mean age of the 1,002 patients was 35.45 years and there were 290 women and 712 men. Respective measurements were as follows: patella length, width, and thickness, 40.3 mm, 40.2 mm, and 18.6 mm, respectively; patellar tendon length, width, and insertional thickness, 45.2 mm, 27.2 mm, and 5.7 mm, respectively; Insall-Salvati ratio, 1.13; overall graft length, 90.2 mm; and effective tendon length, 26.1 mm. @*Conclusions@#A simple MRI analysis can give us valuable inputs on BTB graft morphometry. The values can also help us with the near-perfect graft harvest. The intraoperative complication of graft tunnel mismatch can be avoided by predicting the overall graft length, effective tendon length, tibial tunnel length, and patellar position using the measured parameters on MRI.

Lipoma Arborescens: can we afford to miss it?

INTRODUCTION: Lipoma Arborescens is an extremely rare, benign lesion effecting the synovial tissue of joints. It is characterized by villous lipomatous proliferation of the synovial tissue. The aim of our study was to evaluate its diagnostic features and analyse the functional outcome of arthroscopic management. METHODS: We studied 13 patients who were diagnosed to have lipoma arborescens at our institution during the period from October 2005 to October 2019. All patients underwent arthroscopic synovectomy. Histopathological examination confirmed the diagnosis. Pre-operative and post-operative functional assessment was done using Tegner Lysholm score. RESULTS: Mean age was 46.6 years. All patients presented with progressive swelling of knee joint, while 6 patients also complained of pain. Average duration of symptoms was 34 months. All the patients were diagnosed based on MRI findings. Tegner Lysholm scoring at last follow up visit, had 11 patients with excellent outcome, 1 patient with good outcome, and 1 patient with fair outcome. None of the patients had recurrence, nor underwent any subsequent procedure of the operated joint. CONCLUSIONS: Lipoma arborescens is a rare condition which should be a differential in patients with mono-articular swelling of the knee joint, and can be confirmed with MRI. It should not be misdiagnosed or missed at early stages as prolonged duration of symptoms and delay in treatment is likely to lead to development of secondary arthritis of the joint. Arthroscopic synovectomy showed good functional outcome and no recurrence.

Platelet-Rich Plasma (PRP) Injection in Sports Injuries.

BACKGROUND: Sports injuries are very common, and the management demands high degrees of skills and best techniques for an early return to play. The use of Platelet Rich Plasma (PRP) injections in the treatment of tendon, muscle and ligament injuries has become popular. This study observes the outcomes of PRP injections in sports injuries. METHODS: Forty-eight athletes (mean age 29.93 ± 8.48, Male: 37, Female: 11) presenting to a sports medicine centre with different sports injuries with symptom duration (2.81 ± 1.94) months were given PRP injections (single or multiple) four weeks apart with maximum number of injections up to three depending upon the clinical condition, Pre and Post VAS scores. Specific rehabilitation program was administered and compliance was graded by Sports Injury Rehabilitation Adherence Scale (SIRAS). A 1 year follow-up of cases was done for assessing player satisfaction and return to play. RESULTS: Pre-procedure (7.25 ± 0.70) and post-procedure (2.42 ± 0.74) VAS score for all athletes showed significant difference with a p value at 0.0001. The average number of injections was 1.35 ± 1.41 with 72.91% requiring only one injection while 18.75% and 8.33% required two and three injections, respectively. CONCLUSION: Athletes who required a single injection for acute injuries of lower grade returned to sports activity earlier than those who required multiple injections for chronic injuries. PRP injection has optimal effects on sports injuries not responding to conservative management.

Effect of Refractory Tantalum Metal Filling on the Microstructure and Thermoelectric Properties of Co4Sb12 Skutterudites.

We report a systematic investigation of the microstructure and thermoelectric properties of refractory element-filled nanostructured Co4Sb12 skutterudites. The refractory tantalum (Ta) metal-filled Co4Sb12 samples (Ta x Co4Sb12 (x = 0, 0.4, 0.6, and 0.8)) are synthesized using a solid-state synthesis route. All the samples are composed of a single skutterudite phase. Meanwhile, nanometer-sized equiaxed grains are present in the Ta0.2Co4Sb12 and Ta0.4Co4Sb12 samples, and bimodal distributions of equiaxed grains and elongated grains are observed in Ta0.6Co4Sb12 and Ta0.8Co4Sb12 samples. The dominant carrier type changes from electrons (n-type) to holes (p-type) with an increase in Ta concentration in the samples. The power factor of the Ta0.6Co4Sb12 sample is increased to 2.12 mW/mK2 at 623 K due to the 10-fold reduction in electrical resistivity. The lowest lattice thermal conductivity observed for Ta0.6Co4Sb12 indicates the rattling action of Ta atoms and grain boundary scattering. Rietveld refinement of XRD data and the analysis of lattice thermal conductivity data using the Debye model confirm that Ta occupies at the voids as well as the Co site. The figure of merit (ZT) of ∼0.4 is obtained in the Ta0.6Co4Sb12 sample, which is comparable to single metal-filled p-type skutterudites reported to date. The thermoelectric properties of the refractory Ta metal-filled skutterudites might be useful to achieve both n-type and p-type thermoelectric legs using a single filler atom and could be one of replacements of the rare earth-filled skutterudites with improved thermoelectric properties.

Discovery of carbon nanotubes in sixth century BC potteries from Keeladi, India.

Unique black coatings were observed in the inner wall of pottery shreds excavated from Keeladi, Tamilnadu, India. Raman spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were used to understand the nature of the coating. The analysis revealed the presence of single, multi-walled carbon nanotubes and layered sheets in the coating. The average diameter of single-walled carbon nanotube found to be about 0.6 ± 0.05 nm. This is the lowest among the single-walled carbon nanotubes reported from artefacts so far and close to the theoretically predicted value (0.4 nm). These nanomaterials were coated in the pottery's that date backs to sixth century BC, and still retain its stability and adhesion. The findings of nano materials in the pre-historic artifacts, its significance and impact are discussed in this article.

Evaluation of regeneration of semitendinosus tendon using ultrasound imaging and isokinetic strength testing after graft harvest for arthroscopic anterior cruciate ligament reconstruction.

BACKGROUND: A lot of the research has been done worldwide evaluating the capacity of the semitendinosus tendon to regenerate which has not been conducted in the Indian population. STUDY DESIGN: 31 patients who underwent unilateral ACL reconstruction with hamstrings were taken into study. All patients underwent ultrasonography imaging of both knees and bilateral isokinetic flexion strength assessment at a one-year postoperative period. Images were obtained at three levels and their dimensions are compared with normal side. Isokinetic testing of the knee is done to evaluate the flexion deficit and is compared to the uninvolved knee. RESULTS: Out of a total of 31 patients, 14 patients showed no regeneration, 17 showed regeneration at various levels. On isokinetic testing patients with no regeneration showed the highest mean flexion deficit. CONCLUSION: The semitendinosus tendon and its regeneration can be visualized well using ultrasonography. After semitendinosus harvesting, the flexion strength will be decreased as compared to the normal knee. The flexion strength in patients who have a regenerated tendon will be higher as compared to those who have no regeneration.

Rowing Injuries in Elite Athletes: A Review of Incidence with Risk Factors and the Role of Biomechanics in Its Management.

BACKGROUND: Rowing is an Olympic sport gaining popularity in India and injuries are common in these athletes. Determinants of performance, injury risk and training are all interrelated in rowing. Injuries result from various risk factors including fitness issues and improper techniques. Rowers should have adequate leg extension strength and lumbo-pelvic coordination to produce and transmit power from the legs to the oar handle. Biomechanical analysis of the rowing stroke can help in preventing injuries and optimise technique for best performance. It involves a detailed and systematic observation of movement patterns to establish the quality of the movement and provide feedback to the rower about the key variables affecting performance and injury risk. Kinetics such as foot forces and kinematics such as key joint angles can be accurately measured by instrumented foot stretcher and three-dimensional motion capture. AIM: To do a detailed review of literature regarding the incidence and risk factors for rowing injuries and to get an insight on the role of biomechanics in its management. MATERIALS AND METHODS: Literature review was carried out with standard academic search engines and databases including Science Direct, PubMed and Google Scholar using keywords of relevance. A total number of 38 articles were analysed and results were collated to compile this review report. RESULTS: Lumbar spine is most commonly injured (up to 53%), followed by rib cage (9-10%) and shoulder and other anatomical areas. Rowers with a trunk-driven rowing action will have a lower hip:trunk score and carry a high injury risk. A player with lumbar injury will take a minimum of 3-4 months to recover. CONCLUSION: Rowing injuries are common. Regular screening of the rowing athletes by comprehensive fitness and biomechanics assessment will help in prevention of injuries. Rowers need to be tested for pain, strength, flexibility, reproducibility of rowing action with modified mechanics, coordination, fatigue level, explosive power, aerobic and anaerobic endurance. Early recognition of risk factors and timely intervention is the key aspect of a successful return to play.

Ultrahigh Average Thermoelectric Figure of Merit, Low Lattice Thermal Conductivity and Enhanced Microhardness in Nanostructured (GeTe)x (AgSbSe2 )100-x.

Waste heat sources are generally diffused and provide a range of temperatures rather than a particular temperature. Thus, thermoelectric waste heat to electricity conversion requires a high average thermoelectric figure of merit (ZTavg ) of materials over the entire working temperature along with a high peak thermoelectric figure of merit (ZTmax ). Herein an ultrahigh ZTavg of 1.4 for (GeTe)80 (AgSbSe2 )20 [TAGSSe-80, T=tellurium, A=antimony, G=germanium, S=silver, Se=selenium] is reported in the temperature range of 300-700 K, which is one of the highest values measured amongst the state-of-the-art Pb-free polycrystalline thermoelectric materials. Moreover, TAGSSe-80 exhibits a high ZTmax of 1.9 at 660 K, which is reversible and reproducible with respect to several heating-cooling cycles. The high thermoelectric performance of TAGSSe-x is attributed to extremely low lattice thermal conductivity (κlat ), which mainly arises due to extensive phonon scattering by hierarchical nano/meso-structures in the TAGSSe-x matrix. Addition of AgSbSe2 in GeTe results in κlat of ≈0.4 W mK-1 in the 300-700 K range, approaching to the theoretical minimum limit of lattice thermal conductivity (κmin ) of GeTe. Additionally, (GeTe)80 (AgSbSe2 )20 exhibits a higher Vickers microhardness (mechanical stability) value of ≈209 kgf mm-2 compared to the other state-of-the-art metal chalcogenides, making it an important material for thermoelectrics.

Surgeons often underestimate the amount of blood loss in replacement surgeries / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To assess the accuracy of the clinically estimated blood loss (EBL) when compared with the actual blood loss (ABL) in replacement surgeries.</p><p><b>METHODS</b>This prospective study was done in Sri Ramachandra Medical Centre from April 2011 to April 2013. Altogether 140 patients undergoing total hip replacement or total knee replacement were included with the inclusion criteria being patients with haemoglobin higher than 100 g/ml and coagulation profile within normal limits. Exclusion criteria were intake of anti-platelet drug or anti-coagulant, bleeding disorders, thrombotic episode, and haematological disorders. There were 65 men and 75 women. In this study, the consultants were free to use any clinical method to estimate the blood loss, including counting the blood-soaked mops and gauze pieces (estimating the volume of blood carried in all the mops and gauzes), measuring blood lost to suction bottles and blood in and around the operative field. The ABL was calculated based on a modification of the Gross's formula using haematocrit values.</p><p><b>RESULTS</b>In 42 of the 140 cases, the EBL exceeded the ABL. These cases had a negative difference in blood loss (or DIFF-BL<0) and were included in the overestimation group, which accounted for 30% of the study population. Of the remaining 98 cases (70%), the ABL exceeded the EBL. Therefore they were put into the underestimation group who had a positive difference in blood loss (DIFF-BL>0). We found that when the average blood loss was small, the accuracy of estimation was high. But when the average blood loss exceeded 500 ml, the accuracy rate decreased significantly. This suggested that clinical estimation is inaccurate with the increase of blood loss.</p><p><b>CONCLUSION</b>This study has shown that using clinical estimation alone to guide blood transfusion is inadequate. In this study, 70% of patients had their blood loss underestimated, proving that surgeons often underestimate blood loss in replacement surgeries.</p>