Clinical and functional outcomes of 405 Achilles tendon ruptures after a minimum follow-up of 1 year.

OBJECTIVE: The results of surgical versus conservative treatment of acute Achilles tendon ruptures are still controversial. The objective of this study was to compare surgical and conservative treatment at a minimum follow-up of 1 year in terms of the complications, functional outcomes and clinical results. HYPOTHESES: There is no difference in the complications, clinical results and functional outcomes between the two treatment groups. There is no difference in the occurrence of complications or the clinical results due to the immobilization or rehabilitation protocols. METHODS: This was a retrospective comparative, multicenter, non-randomized study of acute Achilles tendon ruptures treated between 01/01/2018 and 31/12/2019 at 21 study sites in France. All patients who received surgical or conservative treatment were included. The demographics, sports participation, nature of treatment, immobilization parameters (type, duration, position) and rehabilitation protocol were collected. Rerupture, general and specific complications, clinical results (heel-rise test, single-leg hop, calf circumference, ankle dorsiflexion) and the functional outcomes (ATRS, VISA-A, EFAS, SF-12) were collected at the final review. RESULTS: Four hundred five patients were reviewed at a mean follow-up of 24 (±7) months. Surgical treatment was done in 372 patients (92%) and conservative treatment in 33 patients (8%), with these two sets of patients having comparable preoperative characteristics. There was a similar number of reruptures in the conservative group (3 cases, 9%) as in the surgical group (15 cases, 4%) (p=0.176). There were more general complications in the conservative group (24%) than in the surgical group (11%) (p=0.04). There was a 9% rate of surgery-related complications (infection, nerve damage, anesthesia after-effects). The ATRS (p=0.017), EFAS Total (p=0.013), EFAS daily living (p=0.008), and SF-12 physical (p=0.01) were better in the surgical group. Strict then relative immobilization provided the best balance between functional recovery (EFAS total of 33, p<0.01) and tendon lengthening (0°, p=0.01) without increasing the occurrence of rerupture (2%, p=0.18). Early weightbearing accompanied by immobilization and rehabilitation within 30 days did not lead to more reruptures than if it was started beyond 30 days (p=0.082 and p=0.07). CONCLUSIONS: This study found no differences in the number of reruptures between surgical treatment and conservative treatment of acute Achilles tendon ruptures. Surgical treatment led to better clinical results but had a variable effect on improving the functional scores. No matter which treatment is used, in the ideal case, 3 weeks of strict immobilization in equinus should be followed by progressive reduction over the next 3 weeks. Early weightbearing and mobilization within 30 days did not increase the risk of rerupture; it actually optimized the clinical and functional outcomes. LEVEL OF EVIDENCE: III; retrospective comparative, non-randomized.

Patients with Long COVID continue to experience significant symptoms at 12 months and factors associated with improvement: A prospective cohort study in France (PERSICOR).

OBJECTIVES: This study examines long COVID symptoms course over 12 months, their impact on daily life, and associated factors for symptom relief. METHODS: A prospective cohort study included 231 participants with long COVID at 12-month follow-up. Data on characteristics, symptom course, and remission were collected using a questionnaire and a remission scale. Poisson regression models were used to estimate the prevalence rate ratio (PRR) and 95% confidence intervals (CIs) for factors associated with symptom improvement. RESULTS: Of the 231 participants, 63.2% developed SARS-CoV-2 antibodies before COVID-19 vaccination. At 12 months, only 8.7% (95% CI: 5.4-13.1%) reported complete remission, while 28.6% noted significant improvement. Most symptoms remained prevalent: asthenia (83.1%), neurocognitive/neurological (93.9%), cardiothoracic (77.9%), Musculoskeletal (78.8%). During long COVID, 62.2% stopped working, and only 32.5% resumed full-time professional activities. Presence of SARS-CoV-2 antibodies before vaccination increased the probability of improvement (aPRR: 1.60, P = 0.028), while ageusia at initial long COVID phase decreased the probability (aPRR: 0.38, P = 0.007). CONCLUSIONS: Long-COVID symptoms persisted in the majority of participants after 12 months, with significant impacts on daily life and work. SARS-CoV-2 antibodies were associated with better prognosis, while persistent ageusia indicated a lower probability of improvement. These findings highlight the need for ongoing support and care for individuals with long COVID.

Construction and validation of a functional diagnostic score in anterior cruciate ligament ruptures of the knee in the immediate post-traumatic period. Preliminary results of a multicenter prospective study.

INTRODUCTION: Knee ligament injuries are frequent and their number is constantly increasing with the development of sports activities. Dynamic knee maneuvers usually make it possible to diagnose anterior cruciate ligament (ACL) injuries but they remain difficult to perform in the early post-traumatic phase. This leads to the almost systematic use of MRI scans, many of which turn out to be superfluous. The aim of this study was to construct a screening score based solely on history-taking, in order to help diagnose ACL injuries, and to define thresholds that could help inform recommendations for MRI usage. The hypothesis was that this score could distinguish a population of patients with a ruptured ACL from a population of patients with other knee injuries. MATERIAL AND METHODS: This prospective multicenter study included 166 patients. Patients were included if they were between 18 and 55 years of age, with knee trauma that had occurred in the last 10 days, and without a bone fracture on standard radiographs. They were excluded if the trauma required immediate surgical management and if they had a history of knee trauma. The screening score was completed by the physician. The score included the following items: assessment of pain, immediate post-traumatic functional impairment, notion of a "pop", feeling of instability and presence of a swelling. An MRI was systematically performed and the patient consulted a referring physician to compare the initial score with the diagnosis. RESULTS: Eighty-six patients had an injured ACL and 80 had a healthy ACL. Two thresholds could be identified. For a score lower than 4, the risk of an ACL injury was low with a sensitivity of 96% and a negative predictive value of 87%. For a score above 8, the ACL injury was highly probable with a specificity of 88% and a positive predictive value of 83%. DISCUSSION/CONCLUSION: The score was able to distinguish a population of patients with a ruptured ACL from a population of patients with other knee injuries. These preliminary results confirm that the selected items are relevant and that the score can help improve the diagnostic orientation of patients with recent knee trauma. Increasing the sample size in combination with an analysis of influencing factors will determine whether the performance of this score can be refined. LEVEL OF EVIDENCE: II prospective multicenter study.

The awareness of injury prevention programmes is insufficient among French- and German-speaking sports medicine communities in Europe.

PURPOSE: Evaluate the current state of sports injury prevention perception, knowledge and practice among sports medicine professionals located in Western Europe and involved in injury prevention. METHODS: Members of two different sports medicine organizations (GOTS and ReFORM) were invited to complete a web-based questionnaire (in German and in French, respectively) addressing perception, knowledge and implementation of sports injury prevention through 22 questions. RESULTS: 766 participants from a dozen of countries completed the survey. Among them, 43% were surgeons, 23% sport physicians and 18% physiotherapists working mainly in France (38%), Germany (23%) and Belgium (10%). The sample rated the importance of injury prevention as "high" or "very high" in a majority of cases (91%), but only 54% reported to be aware of specific injury prevention programmes. The French-speaking world was characterized by lower levels of reported knowledge, unfamiliarity with existing prevention programmes and less weekly time spent on prevention as compared to their German-speaking counterparts. Injury prevention barriers reported by the respondents included mainly insufficient expertise, absence of staff support from sports organizations and lack of time. CONCLUSION: There is a lack of awareness regarding injury prevention concepts among sports medicine professionals of the European French- and German-speaking world. This gap varied according to the professional occupation and working country. Relevant future paths for improvement include specific efforts to build awareness around sports injury prevention. LEVEL OF EVIDENCE: Level IV.

How Was Studied the Effect of Manual Wheelchair Configuration on Propulsion Biomechanics: A Systematic Review on Methodologies.

Background: For both sports and everyday use, finding the optimal manual wheelchair (MWC) configuration can improve a user's propulsion biomechanics. Many studies have already investigated the effect of changes in MWC configuration but comparing their results is challenging due to the differences in experimental methodologies between articles. Purpose: The present systematic review aims at offering an in-depth analysis of the methodologies used to study the impact of MWC configuration on propulsion biomechanics, and ultimately providing the community with recommendations for future research. Methods: The reviewing process followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart on two databases (Scopus and PubMed) in March 2022. Results: Forty-five articles were included, and the results highlighted the multiplicity of methodologies regarding different experimental aspects, including propulsion environment, experimental task, or measurement systems, for example. More importantly, descriptions of MWC configurations and their modifications differed significantly between studies and led to a lack of critical information in many cases. Discussion: Studying the effect of MWC configuration on propulsion requires recommendations that must be clarified: (1) the formalism chosen to describe MWC configuration (absolute or relative) should be consistent with the type of study conducted and should be documented enough to allow for switching to the other formalism; (2) the tested MWC characteristics and initial configuration, allowing the reproduction or comparison in future studies, should be properly reported; (3) the bias induced by the experimental situation on the measured data must be considered when drawing conclusions and therefore experimental conditions such as propulsion speed or the effect of the instrumentation should be reported. Conclusion: Overall, future studies will need standardization to be able to follow the listed recommendations, both to describe MWC configuration and mechanical properties in a clear way and to choose the experimental conditions best suited to their objectives.

Golf Swing Biomechanics: A Systematic Review and Methodological Recommendations for Kinematics.

Numerous studies have been conducted to investigate golf swing performance in both preventing injury and injury occurrence. The objective of this review was to describe state-of-the-art golf swing biomechanics, with a specific emphasis on movement kinematics, and when possible, to suggest recommendations for research methodologies. Keywords related to biomechanics and golf swings were used in scientific databases. Only articles that focused on golf-swing kinematics were considered. In this review, 92 articles were considered and categorized into the following domains: X-factor, crunch factor, swing plane and clubhead trajectory, kinematic sequence, and joint angular kinematics. The main subjects of focus were male golfers. Performance parameters were searched for, but the lack of methodological consensus prevented generalization of the results and led to contradictory results. Currently, three-dimensional approaches are commonly used for joint angular kinematic investigations. However, recommendations by the International Society of Biomechanics are rarely considered.

Development and evaluation of a new methodology for Soft Tissue Artifact compensation in the lower limb.

Skin Marker (SM) based motion capture is the most widespread technique used for motion analysis. Yet, the accuracy is often hindered by Soft Tissue Artifact (STA). This is a major issue in clinical gait analysis where kinematic results are used for decision-making. It also has a considerable influence on the results of rigid body and Finite Element (FE) musculoskeletal models that rely on SM-based kinematics to estimate muscle, contact and ligament forces. Current techniques devised to compensate for STA, in particular multi-body optimization methods, often consider simplified joint models. Although joint personalization with anatomical constraints has improved kinematic estimation, these models yet don't represent a fully reliable solution to the STA problem, thus allowing us to envisage an alternative approach. In this perspective, we propose to develop a conceptual FE-based model of the lower limb for STA compensation and evaluate it for 66 healthy subjects under level walking motor task. Both hip and knee joint kinematics were analyzed, considering both rotational and translational joint motion. Results showed that STA caused underestimation of the hip joint kinematics (up to 2.2°) for all rotational DoF, and overestimation of knee joint kinematics (up to 12°) except in flexion/extension. Joint kinematics, in particular the knee joint, appeared to be sensitive to soft tissue stiffness parameters (rotational and translational mean difference up to 1.5° and 3.4 mm). Analysis of the results using alternative joint representations highlighted the versatility of the proposed modeling approach. This work paves the way for using personalized models to compensate for STA in healthy subjects and different activities.

Development and evaluation of a new procedure for subject-specific tensioning of finite element knee ligaments.

Subject-specific tensioning of ligaments is essential for the stability of the knee joint and represents a challenging aspect in the development of finite element models. We aimed to introduce and evaluate a new procedure for the quantification of ligament prestrains from biplanar X-ray and CT data. Subject-specific model evaluation was performed by comparing predicted femorotibial kinematics with the in vitro response of six cadaveric specimens. The differences obtained using personalized models were comparable to those reported in similar studies in the literature. This study is the first step toward the use of simplified, personalized knee FE models in clinical context such as ligament balancing.

Biomechanical analysis of the golf swing: methodological effect of angular velocity component on the identification of the kinematic sequence.

PURPOSE: The golf swing is a complex whole-body motion for which a proximal-to-distal transfer of the segmental angular velocities from the pelvis to the club is believed to be optimal for maximizing the club head linear velocity. However, previous experimental results about such timing (or kinematic sequence) are contradictory. Nevertheless, methods that were used in these studies differed significantly, in particular, those regarding the component of the angular velocity vector selected for the identification of the kinematic sequence. Hence, the aim of this study was to investigate the effect of angular velocity vector component selection on the identified kinematic sequence. METHODS: Thirteen golfers participated in this study and performed driver swings in a motion capture laboratory. Seven methods based on different component selection of segmental angular velocities (vector norm, component normal-to-sagittal, frontal, transversal and swing planes, segment longitudinal component and a method mixing longitudinal and swing plane components) were tested. RESULTS: Results showed the critical influence of the component chosen to identify the kinematic sequence with almost as many kinematic sequences as the number of tested methods for every golfer. CONCLUSION: One method seems to show the strongest correlation to performance but none of them can be assessed as a reference method for the identification of the golf swing kinematic sequence. Regarding the limited time lag between the different peak occurrences and the uncertainty sources of current materials, development of simulation studies would be more suitable to identify the optimal kinematic sequence for the golf swing.

Criteria for return to running after anterior cruciate ligament reconstruction: a scoping review.

OBJECTIVE: To describe the criteria used to guide clinical decision-making regarding when a patient is ready to return to running (RTR) after ACL reconstruction. DESIGN: Scoping review. DATA SOURCES: The MEDLINE (PubMed), EMBASE, Web of Science, PEDro, SPORTDiscus and Cochrane Library electronic databases. We also screened the reference lists of included studies and conducted forward citation tracking. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Reported at least one criterion for permitting adult patients with primary ACL reconstruction to commence running postoperatively. RESULTS: 201 studies fulfilled the inclusion criteria and reported 205 time-based criteria for RTR. The median time from when RTR was permitted was 12 postoperative weeks (IQR=3.3, range 5-39 weeks). Fewer than one in five studies used additional clinical, strength or performance-based criteria for decision-making regarding RTR. Aside from time, the most frequently reported criteria for RTR were: full knee range of motion or >95% of the non-injured knee plus no pain or pain <2 on visual analogue scale; isometric extensor limb symmetry index (LSI)>70% plus extensor and flexor LSI>70%; and hop test LSI>70%. CONCLUSIONS: Fewer than one in five studies reported clinical, strength or performance-based criteria for RTR even though best evidence recommends performance-based criteria combined with time-based criteria to commence running activities following ACL reconstruction.

Femur, tibia and fibula bone templates to estimate subject-specific knee ligament attachment site locations.

In-vivo estimates of the positions of knee ligament attachment sites are crucial for subject-specific knee modelling. The present study provides template digital models of femur, tibia and fibula that embed the positions of centroids of the origins and insertions of cruciate and collateral ligaments, along with information on their dispersion related to inter-individual variability. By using a shape transformation procedure of choice, these templates can be made to match anatomical information measured on a subject under analysis. Generic bone digital models of the femur, tibia and fibula were first chosen as bone templates. Ligament attachment areas were accurately identified through dissection on the bones of 11 knee specimens, and marked using radio opaque paint. Digital models of these bones embedding the positions of the centroids of the identified ligament attachment areas were thereafter obtained using medical imaging techniques. These centroids were mapped onto the relevant bone template, thus obtaining a cloud of 11 points for each attachment site, and descriptive statistics of the position of these points were thereafter determined. Dispersion of these positions, essentially due to inter-individual variability, was below 6mm for all attachment areas. The accuracy with which subject-specific ligament attachment site positions may be estimated using the bone template models provided in this paper was also assessed using the above-mentioned 11 specimens data set, and a leave-one-out cross validation approach. Average accuracy was found to be 3.3±1.5mm and 5.8±2.9mm for femoral and tibial/fibular attachment sites, respectively.

Reliable protocol for shear wave elastography of lower limb muscles at rest and during passive stretching.

Development of shear wave elastography gave access to non-invasive muscle stiffness assessment in vivo. The aim of the present study was to define a measurement protocol to be used in clinical routine for quantifying the shear modulus of lower limb muscles. Four positions were defined to evaluate shear modulus in 10 healthy subjects: parallel to the fibers, in the anterior and posterior aspects of the lower limb, at rest and during passive stretching. Reliability was first evaluated on two muscles by three operators; these measurements were repeated six times. Then, measurement reliability was compared in 11 muscles by two operators; these measurements were repeated three times. Reproducibility of shear modulus was 0.48 kPa and repeatability was 0.41 kPa, with all muscles pooled. Position did not significantly influence reliability. Shear wave elastography appeared to be an appropriate and reliable tool to evaluate the shear modulus of lower limb muscles with the proposed protocol.

Biomechanical evaluation of four femoral fixation configurations in a simulated anterior cruciate ligament replacement using a new generation of Ligament Advanced Reinforcement System (LARS™ AC).

BACKGROUND: Recent improvements in manufacturing of biomaterials have made available a new generation of artificial ligaments with better biocompatibility and design that have led to a new interest in using them for ACL reconstructions. PURPOSE: To evaluate the biomechanical characteristics of four femoral fixations using a Ligament Advanced Reinforcement System (LARS™ AC; LARS, Arc sur Tille, France) for anterior cruciate ligament replacement. METHOD: Six femoral ACL fixations in four configurations using fresh calf femurs with an interference titanium screw inserted inside to outside, an interference titanium screw inserted outside to inside, an interference titanium screw inserted inside to outside with a staple and a new transversal cortical suspension device developed by LARS™ were compared in a static loading and failure test. Output values were ultimate strength, graft slippage, mode of failure, energy to failure and stiffness. RESULTS: The transversal fixation performed with a significantly higher failure load than others (1804 N) (p < 0.001), whereas there were no significant differences between the three fixations with interference screws. There were no significant differences of stiffness between all fixations, and the transversal device had a significantly higher graft slippage (13.1 mm) than others (all p < 0.01). CONCLUSIONS: In this in vitro evaluation, the transversal fixation exhibited better biomechanical performance under static solicitations than others. The transversal device is expected to provide better clinical results than the well-established screw system fixations for femoral ACL fixation. CLINICAL RELEVANCE: Laboratory investigation (Level 2).

Distribution and variability study of the femur cortical thickness from computer tomography.

In the context of patient-specific 3D bone reconstruction, enhancing the surface with cortical thickness (COT) opens a large field of applications for research and medicine. This functionality calls for database analysis for better knowledge of COT. Our study provides a new approach to reconstruct 3D internal and external cortical surfaces from computer tomography (CT) scans and analyses COT distribution and variability on a set of asymptomatic femurs. The reconstruction method relies on a short (∼5 min) initialisation phase based on 3D reconstruction from biplanar CT-based virtual X-rays and an automatic optimisation phase based on intensity-based cortical structure detection in the CT volume, the COT being the distance between internal and external cortical surfaces. Surfaces and COT show root mean square reconstruction errors below 1 and 1.3 mm. Descriptions of the COT distributions by anatomical regions are provided and principal component analysis has been applied. The first mode, 16-50% of the variance, corresponds to the variation of the mean COT around its averaged shape; the second mode, 9-28%, corresponds to a fine variation of its shape. A femur COT model can, therefore, be described as the averaged COT distribution in which the first parameter adjusts its mean value and a second parameter adjusts its shape.

PolyNaSS bioactivation of LARS artificial ligament promotes human ligament fibroblast colonisation in vitro.

BACKGROUND: Introduction of a new generation of artificial ligaments for ACL reconstruction, the Ligament Augmentation and Reconstruction System (LARS), gives promising clinical results [1]. The current literature supports the use of LARS from short to medium term. To go even further to improve the biocompatibility of this biomaterial, poly(sodium styrene sulfonate) (polyNaSS) was grafted onto its surface. Studies using sheep animal model showed improvement of knee functionalities with this grafted artificial ligament and a better adhesion of human cell lines. OBJECTIVES: To better understand this in vivo improvement of integration with the bioactivated artificial prosthesis, in vitro studies were leaded using human ligament fibroblasts. METHODS: Human ligament fibroblasts isolated from human ruptured ACL were amplified and seeded onto poly(NaSS) grafted and non-grafted PET scaffold (Lars ligament) under standard culture conditions. Cellularized fibers were observed under scanning electron microscopy and histological and immunohistological studies were performed. RESULTS: Cells are localized around the grafted PET fibers of the bioactive ligament and penetrate in the scaffold. On ungrafted fibers, cells stay around the scaffold. On grafted fibers, collagen I appears strongly organized whereas is thin and dispersed on non grafted fibers. Finally, grafting altered localization of decorin. CONCLUSIONS: PolyNaSS grafting enhances human ligament fibroblast organisation in vitro in contact with biomaterial and improves collagen and decorin deposits around fibers.

A method for the field assessment of rolling resistance properties of manual wheelchairs.

This article presents an examination and validation of a method to measure the field deceleration of a manual wheelchair (MWC) and to calculate the rolling resistances properties of the front and rear wheels. This method was based on the measurements of the MWC deceleration for various load settings from a 3D accelerometer. A mechanical model of MWC deceleration was developed which allowed computing the rolling resistance factors of front and rear wheels on a tested surface. Four deceleration sets were conducted on two paths on the same ground to test the repeatability. Two other deceleration sets were conducted using different load settings to compute the rolling resistance parameters (RPs). The theoretical decelerations of three load settings were computed and compared with the measured decelerations. The results showed good repeatability (variations of measures represented 6-11% of the nominal values) and no statistical difference between the path results. The rolling RPs were computed and their confidence intervals were assessed. For the last three sets, no significant difference was found between the theoretical and measured decelerations. This method can determine the specific rolling resistance properties of the wheels of a MWC, and be employed to establish a catalogue of the rolling resistance properties of wheels on various surfaces.

Three-dimensional morphologic study of the child's hip: which parameters are reproducible?

BACKGROUND: Biplanar x-ray images obtained with patients in a standing weightbearing position allow reconstruction of three-dimensional (3-D) bone geometries, with lower radiation exposure than CT scans and better bone definition than MRI. QUESTIONS/PURPOSES: We determined the reproducibility of 3-D parameter values of the hips and pelves of healthy children, using biplanar x-ray images. METHODS: We built 3-D models of the hips of 33 children without musculoskeletal problems: 10 subjects younger than 9 years and 23 who were 9 years or older. Three anatomic landmarks and nine hip and pelvic parameters were computed for each reconstruction. To determine the reliability of these landmarks and parameters, each bone was reconstructed four times by two independent observers, leading to a total of 264 reconstructions, and parameters were studied for the two age groups and compared between dancers and nondancers. RESULTS: Taking into account all reconstructions, the interobserver reproducibility ranged from 2 to 4 mm for landmark positions or distance parameters, and 2° to 6° for angular parameters. The most reproducible point was the center of the femoral head (range, 0.2-17 mm). The distance between this center and its projection on the plane fitting the edge of the acetabulum, and the pelvic tilt were the most reproducible parameters. CONCLUSIONS: Reproducible 3-D reconstructions of hips and pelves of children were possible using biplanar x-ray images, regardless of the children's ages. Although we report preliminary values for 3-D parameters in healthy children's hips, further work is needed to obtain direct validation of our parameters using CT reconstructions of cadaveric specimens to avoid high doses of radiation.

Estimation of temporal parameters during sprint running using a trunk-mounted inertial measurement unit.

The purpose of this study was to identify consistent features in the signals supplied by a single inertial measurement unit (IMU), or thereof derived, for the identification of foot-strike and foot-off instants of time and for the estimation of stance and stride duration during the maintenance phase of sprint running. Maximal sprint runs were performed on tartan tracks by five amateur and six elite athletes, and durations derived from the IMU data were validated using force platforms and a high-speed video camera, respectively, for the two groups. The IMU was positioned on the lower back trunk (L1 level) of each athlete. The magnitudes of the acceleration and angular velocity vectors measured by the IMU, as well as their wavelet-mediated first and second derivatives were computed, and features related to foot-strike and foot-off events sought. No consistent features were found on the acceleration signal or on its first and second derivatives. Conversely, the foot-strike and foot-off events could be identified from features exhibited by the second derivative of the angular velocity magnitude. An average absolute difference of 0.005 s was found between IMU and reference estimates, for both stance and stride duration and for both amateur and elite athletes. The 95% limits of agreement of this difference were less than 0.025 s. The results proved that a single, trunk-mounted IMU is suitable to estimate stance and stride duration during sprint running, providing the opportunity to collect information in the field, without constraining or limiting athletes' and coaches' activities.