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Is there a relation between loss of shoulder external rotation and sternoclavicular joint disorders?Acta Bio-medica : Atenei Parmensis Jun 2023Scapulothoracic movements are essential in shoulder kinematics and can partially compensate stiffness and loss of motion of glenohumeral joint. The scapulothoracic...
BACKGROUND AND AIM
Scapulothoracic movements are essential in shoulder kinematics and can partially compensate stiffness and loss of motion of glenohumeral joint. The scapulothoracic movement is strictly dependent on the translation and rotation of the clavicle at the sternoclavicular joint (SCJ), this being the only true joint between the axial and the upper appendicular skeleton. Aim of the study is to define a possible correlation between loss of shoulder external rotation following surgery for anterior shoulder instability and long-term sternoclavicular joint disorders.
METHODS
A group of 20 patients and a group of 20 healthy volunteers were studied. Results: In the statistical analysis of the patient group and of the two groups jointly, the association between the reduction of shoulder external rotation and the onset of disorder of SCJ appeared statistically significant.
CONCLUSIONS
Our results provide support for an association between some disorders of the SCJ and the alterations of the shoulder kinematics associated with a reduction of ROM in external rotation. Our sample is too small to allow definitive conclusions to be drawn. These results, if confirmed by larger studies, could help us further clarify the complex kinematics of the shoulder girdle.
Topics: Humans; Shoulder; Sternoclavicular Joint; Shoulder Joint; Joint Instability; Clavicle; Biomechanical Phenomena; Range of Motion, Articular
PubMed: 37366195
DOI: 10.23750/abm.v94iS2.12524 -
Journal of Applied Physiology... Apr 2021Humans choose work-minimizing movement strategies when interacting with compliant surfaces. Our ankles are credited with stiffening our lower limbs and maintaining the...
Humans choose work-minimizing movement strategies when interacting with compliant surfaces. Our ankles are credited with stiffening our lower limbs and maintaining the excursion of our body's center of mass on a range of surface stiffnesses. We may also be able to stiffen our feet through an active contribution from our plantar intrinsic muscles (PIMs) on such surfaces. However, traditional modeling of the ankle joint has masked this contribution. We compared foot and ankle mechanics and muscle activation on low, medium, and high stiffness surfaces during bilateral hopping using a traditional and anatomical ankle model. The traditional ankle model overestimated work and underestimated stiffness compared with the anatomical model. Hopping on a low stiffness surface resulted in less longitudinal arch compression with respect to the high stiffness surface. However, because midfoot torque was also reduced, midfoot stiffness remained unchanged. We observed lower activation of the PIMs, soleus, and tibialis anterior on the low and medium stiffness conditions, which paralleled the pattern we saw in the work performed by the foot and ankle. Rather than performing unnecessary work, participants altered their landing posture to harness the energy stored by the sprung surface in the low and medium conditions. These findings highlight our preference to minimize mechanical work when transitioning to compliant surfaces and highlight the importance of considering the foot as an active, multiarticular, part of the human leg. When seeking to understand how humans adapt their movement to changes in substrate, the role of the human foot has been neglected. Using multi-segment foot modeling, we highlight the importance of adaptable foot mechanics in adjusting to surfaces of different compliance. We also show, via electromyography, that the adaptations are under active muscular control.
Topics: Adaptation, Physiological; Ankle; Ankle Joint; Biomechanical Phenomena; Electromyography; Humans; Leg; Muscle, Skeletal
PubMed: 33571058
DOI: 10.1152/japplphysiol.00401.2020 -
The Journal of Bone and Joint Surgery.... Aug 2014Recurrent shoulder instability is commonly associated with glenoid bone defects. Coracoid transfer procedures, such as the Bristow and Latarjet procedures, are... (Comparative Study)
Comparative Study
BACKGROUND
Recurrent shoulder instability is commonly associated with glenoid bone defects. Coracoid transfer procedures, such as the Bristow and Latarjet procedures, are frequently used to address these bone deficiencies. Despite the frequent synonymous labeling of these transfers as the "Bristow-Latarjet" procedure, their true equivalence has not been demonstrated. Therefore, our purpose was to compare the biomechanical effects of these two procedures.
METHODS
Eight cadaveric specimens were tested on a custom shoulder simulator capable of loading nine muscle groups and of accurately orienting the joint throughout shoulder motion. The specimens were tested in the intact state, following Bristow and Latarjet reconstructions of a capsulolabral injury (0% glenoid defect), and following each procedure after creation of 15% and 30% glenoid bone defects. The reconstruction order was randomized. In each condition, joint stiffness (anterior stability) and occurrence of dislocation were assessed in shoulder adduction and abduction with neutral and external rotation.
RESULTS
No significant differences (p < 0.05) in joint stiffness or stability were found between the Bristow and Latarjet reconstructions for the 0% glenoid defect in any joint position. However, substantially greater joint stiffness occurred following the Latarjet procedure, as compared with the Bristow procedure, for the 15% and 30% glenoid bone-loss conditions in adduction with neutral rotation, adduction with external rotation, and abduction with external rotation (average across the three joint positions: 8.6 ± 4.4 N/mm versus 3.9 ± 1.26.7 N/mm [p = 0.034] with 15% bone loss and 7.5 ± 4.4 N/mm versus 3.4 ± 1.5 N/mm [p = 0.045] with 30% bone loss). The Latarjet reconstruction restored the stiffness that had been measured in the intact state in eleven of the twelve tested conditions, whereas the Bristow procedure was successful in only four of the twelve conditions. In addition, during instability testing, three more specimens dislocated following the Bristow reconstruction, compared with the Latarjet procedure, in the 15% defect condition and five more dislocated in the 30% defect condition.
CONCLUSIONS
The Bristow and Latarjet procedures are not equivalent in terms of their effects on glenohumeral joint stiffness and stability in cases of glenoid osseous deficiency.
CLINICAL RELEVANCE
The Bristow and Latarjet procedures have equivalent stabilizing effects in unstable shoulders with preserved glenoid osseous anatomy. However, the Latarjet procedure confers superior stabilization in the setting of substantial glenoid bone loss.
Topics: Aged; Analysis of Variance; Biomechanical Phenomena; Bone Transplantation; Cadaver; Humans; Joint Capsule; Joint Instability; Models, Anatomic; Range of Motion, Articular; Shoulder Dislocation; Shoulder Joint
PubMed: 25143494
DOI: 10.2106/JBJS.M.00627 -
Journal of Orthopaedic Surgery and... Jul 2022Osteoarthritis, a common degenerative disease of articular cartilage, is characterized by degeneration of articular cartilage, changes in subchondral bone structure, and...
BACKGROUND
Osteoarthritis, a common degenerative disease of articular cartilage, is characterized by degeneration of articular cartilage, changes in subchondral bone structure, and formation of osteophytes, with main clinical manifestations including increasingly serious swelling, pain, stiffness, deformity, and mobility deficits of the knee joints. With the advent of the big data era, the processing of mass data has evolved into a hot topic and gained a solid foundation from the steadily developed and improved machine learning algorithms. Aiming to provide a reference for the diagnosis and treatment of osteoarthritis, this paper using machine learning identifies the key feature genes of osteoarthritis and explores its relationship with immune infiltration, thereby revealing its pathogenesis at the molecular level.
METHODS
From the GEO database, GSE55235 and GSE55457 data were derived as training sets and GSE98918 data as a validation set. Differential gene expressions of the training sets were analyzed, and the LASSO regression model and support vector machine model were established by applying machine learning algorithms. Moreover, their intersection genes were regarded as feature genes, the receiver operator characteristic (ROC) curve was drawn, and the results were verified using the validation set. In addition, the expression spectrum of osteoarthritis was analyzed by immunocyte infiltration and the co-expression correlation between feature genes and immunocytes was construed.
CONCLUSION
EPYC and KLF9 can be viewed as feature genes for osteoarthritis. The silencing of EPYC and the overexpression of KLF9 are associated with the occurrence of osteoarthritis and immunocyte infiltration.
Topics: Bone and Bones; Cartilage, Articular; Humans; Knee Joint; Kruppel-Like Transcription Factors; Osteoarthritis; Small Leucine-Rich Proteoglycans
PubMed: 35902862
DOI: 10.1186/s13018-022-03247-6 -
Journal of Orthopaedic Research :... Feb 2016Post-traumatic joint stiffness (PTJS) of the elbow is a debilitating condition that poses unique treatment challenges. While previous research has implicated capsular...
Post-traumatic joint stiffness (PTJS) of the elbow is a debilitating condition that poses unique treatment challenges. While previous research has implicated capsular tissue in PTJS, much regarding the development and progression of this condition remains unknown. The objective of this study was to develop an animal model of post-traumatic elbow contracture and evaluate its potential for studying the etiology of PTJS. The Long-Evans rat was identified as the most appropriate species/breed for development due to anatomical and functional similarities to the human elbow joint. Two surgical protocols of varying severity were utilized to replicate soft tissue damage seen in elbow subluxation/dislocation injuries, including anterior capsulotomy and lateral collateral ligament transection, followed by 6 weeks of unilateral joint immobilization. Following sacrifice, flexion-extension mechanical joint testing demonstrated decreased range-of-motion and increased stiffness for injured-immobilized limbs compared to control and sham animals, where functional impact correlated with severity of injury. Histological evaluation showed increased cellularity, adhesion, and thickness of capsule tissue in injured limbs, consistent with clinical evidence. To our knowledge, this is the first animal model capable of examining challenges unique to the anatomically and biomechanically complex elbow joint. Future studies will use this animal model to investigate mechanisms responsible for PTJS.
Topics: Animals; Contracture; Disease Models, Animal; Elasticity; Elbow Joint; Immobilization; Joint Capsule; Joint Dislocations; Random Allocation; Rats, Long-Evans
PubMed: 26177969
DOI: 10.1002/jor.22981 -
Computational Intelligence and... 2022Based on the Hill muscle model (HMM), a biomechanical model of human hip muscle tendon assisted by elastic external tendon (EET) was preliminarily established to...
Based on the Hill muscle model (HMM), a biomechanical model of human hip muscle tendon assisted by elastic external tendon (EET) was preliminarily established to investigate and analyze the biomechanical transition between the hip joint (HJ) and related muscle tendons. Using the HMM, the optimal muscle fiber length and muscle force scaling variables were introduced by means of constrained optimization problems and were optimized. The optimized HMM was constructed with human parameters of 170 cm and 70 kg. The biomechanical model simulation test of the hip muscle tendon was performed in the automatic dynamic analysis of mechanical systems (ADAMS) software to analyze and optimize the changes in the root mean square error (RMSE), biological moment, muscle moment distribution coefficient (MDC), muscle moment, muscle force, muscle power, and mechanical work of the activation curves of the hip major muscle, iliopsoas muscle, rectus femoris muscle, and hamstring muscle under analyzing the optimized HMM and under different EET auxiliary stiffnesses from the joint moment level, joint level, and muscle level, respectively. It was found that the trends of the output joint moment of the optimized HMM and the biological moment of the human HJ were basically the same, = 0.883 and RMSE = 0.18 Nm/kg, and the average metabolizable energy consumption of the HJ was (243.77 ± 1.59) J. In the range of 35%∼65% of gait cycle (GC), the auxiliary moment showed a significant downward trend with the increase of EET stiffness, when the EET stiffness of the human body was less than 200 Nm/rad, the biological moment of the human HJ gradually decreased with the increase of EET stiffness, and the MDC of the iliopsoas and hamstring muscles gradually decreased; when the EET stiffness was greater than 200 Nm/rad, the increase of the total moment of the extensor muscles significantly increased, the MDC of the gluteus maximus and rectus muscles gradually increased, and the gluteus maximus and hamstring muscle moments and muscle forces gradually increased; the results show that the optimized muscle model based on Hill can reflect the law of human movement and complete the simulation test of HJ movements, which provides a new idea for the analysis of energy migration in the musculoskeletal system of the lower limb.
Topics: Biomechanical Phenomena; Computer Simulation; Gait; Hip Joint; Humans; Muscle, Skeletal; Tendons
PubMed: 35958782
DOI: 10.1155/2022/1987345 -
Journal of Athletic Training 2008Anterior drawer testing of the ankle is commonly used to diagnose lateral ligamentous instability. Our hypothesis was that changing knee and ankle positions would change... (Comparative Study)
Comparative Study
CONTEXT
Anterior drawer testing of the ankle is commonly used to diagnose lateral ligamentous instability. Our hypothesis was that changing knee and ankle positions would change the stability of the ankle complex during anterior drawer testing.
OBJECTIVES
To assess the effects of knee and ankle position on anterior drawer laxity and stiffness of the ankle complex.
DESIGN
A repeated-measures design with knee and ankle position as independent variables.
SETTING
University research laboratory.
PATIENTS OR OTHER PARTICIPANTS
Bilateral ankles of 10 female (age = 19.8 +/- 1.1 years) and 10 male (age = 20.8 +/- 1.2 years) collegiate athletes were tested.
INTERVENTION(S)
Each ankle complex underwent loading using an ankle arthrometer under 4 test conditions consisting of 2 knee positions (90 degrees and 0 degrees of flexion) and 2 ankle positions (0 degrees and 10 degrees of plantar flexion [PF]).
MAIN OUTCOME MEASURE(S)
Recorded anterior laxity (mm) and stiffness (N/mm).
RESULTS
Anterior laxity of the ankle complex was maximal with the knee positioned at 90 degrees of flexion and the ankle at 10 degrees of PF when compared with the knee positioned at 0 degrees of flexion and the ankle at 10 degrees or 0 degrees of PF (P < .001), whereas ankle complex stiffness was greatest with the knee positioned at 0 degrees of flexion and the ankle at 0 degrees of PF (P < .009).
CONCLUSIONS
Anterior drawer testing of the ankle complex with the knee positioned at 90 degrees of flexion and the ankle at 10 degrees of PF produced the most laxity and the least stiffness. These findings indicate that anterior drawer testing with the knee at 90 degrees of flexion and the ankle at 10 degrees of PF may permit better isolation of the ankle capsuloligamentous structures.
Topics: Adult; Ankle Joint; Female; Humans; Joint Instability; Knee Joint; Lateral Ligament, Ankle; Male; Posture; Range of Motion, Articular
PubMed: 18523573
DOI: 10.4085/1062-6050-43.3.242 -
Journal of Applied Physiology... Feb 2021The plantar fascia (PF), a primary contributor of the foot arch elasticity, may experience slack, taut, and stretched states depending on the ankle and...
The plantar fascia (PF), a primary contributor of the foot arch elasticity, may experience slack, taut, and stretched states depending on the ankle and metatarsophalangeal (MTP) joint positions. Since PF has proximodistal site difference in its dimensions and stiffness, the response to applied tension can also be site specific. Furthermore, PF can contribute to supporting the foot arch while being stretched beyond the slack length, but it has never been quantitatively evaluated in vivo. This study investigated the effects of the ankle and MTP joint positions on PF length and localized thickness and shear wave velocity (SWV) at three different sites from its proximal to distal end using magnetic resonance and supersonic shear imaging techniques. During passive ankle dorsiflexion, rise of SWV, an indication of slack length, was observed at the proximal site when the ankle was positioned by 10°-0° ankle plantar flexion with up to 3 mm (+1.5%) increase in PF length. On the other hand, SWV increased at the distal site when MTP joint dorsiflexed 40° with the ankle 30°-20° plantar flexion, and in this position, PF was lengthened up to 4 mm (+2.3%). Beyond the slack length, SWV curvilinearly increased at all measurement sites toward the maximal dorsiflexion angle whereas PF lengthened up to 9 mm (+7.6%) without measurable changes in its thickness. This study provides evidence that the dimensions and SWV of PF change in a site-specific manner depending on the ankle and MTP joint positions, which can diversify foot arch elasticity during human locomotion. Joint angle dependence and site specificity of the plantar fascial dimensions and SWV were examined by combining sagittal magnetic resonance and supersonic shear imaging techniques. We revealed that the site-specific changes in PF SWV were related to joint angle positions, i.e., PF slackness and elasticity changed in varying combinations of ankle and MTP angle. Our findings suggest that PF can elastically support the foot arch throughout the stance phase of human bipedal locomotion.
Topics: Ankle; Ankle Joint; Fascia; Foot; Humans; Metatarsophalangeal Joint; Muscle, Skeletal
PubMed: 33242300
DOI: 10.1152/japplphysiol.00485.2020 -
Journal of Orthopaedic Research :... Aug 2022Pediatric anterior cruciate ligament (ACL) injuries are on the rise, and females experience higher ACL injury risk than males during adolescence. Studies in skeletally...
Pediatric anterior cruciate ligament (ACL) injuries are on the rise, and females experience higher ACL injury risk than males during adolescence. Studies in skeletally immature patients indicate differences in ACL size and joint laxity between males and females after the onset of adolescence. However, functional data regarding the ACL and its anteromedial and posterolateral bundles in the pediatric population remain rare. Therefore, this study uses a porcine model to investigate the sex-specific morphology and biomechanics of the ACL and its bundles throughout skeletal growth. Hind limbs from male and female Yorkshire pigs aged early youth to late adolescence were imaged using magnetic resonance imaging to measure the size and orientation of the ACL and its bundles, then biomechanically tested under anterior-posterior drawer using a robotic testing system. Joint laxity decreased (p < 0.001) while joint stiffness increased (p < 0.001) throughout skeletal growth in both sexes. The ACL was the primary stabilizer against anterior tibial loading, while the functional role of the anteromedial bundle increased with age (p < 0.001), with an earlier increase in males. ACL and posterolateral bundle cross-sectional area and ACL and anteromedial bundle length were larger in males than females during adolescence (p < 0.01 for all), while ACL and bundle sagittal angle remained similar between sexes. Additionally, in situ ACL stiffness versus cross-sectional area regressions were significant across skeletal growth (r = 0.75, p < 0.001 in males and r = 0.64, p < 0.001 in females), but not within age groups. This study has implications for age and sex-specific surgical intervention strategies and suggests the need for human studies.
Topics: Adolescent; Aged; Animals; Anterior Cruciate Ligament; Anterior Cruciate Ligament Injuries; Biomechanical Phenomena; Child; Female; Humans; Joint Instability; Knee Joint; Male; Swine; Tibia
PubMed: 34751996
DOI: 10.1002/jor.25207 -
Knee Surgery, Sports Traumatology,... Jun 2017To determine the mechanisms and extents of popliteus impingements before and after TKA and to investigate the influence of implant sizing. The hypotheses were that (1)...
PURPOSE
To determine the mechanisms and extents of popliteus impingements before and after TKA and to investigate the influence of implant sizing. The hypotheses were that (1) popliteus impingements after TKA may occur at both the tibia and the femur, and (2) even with an apparently well-sized prosthesis, popliteal tracking during knee flexion is modified compared to the preoperative situation.
METHODS
The location of the popliteus in three cadaver knees was measured using computed tomography, before and after implantation of plastic TKA replicas, by injecting the tendon with radiopaque liquid. The pre- and post-operative positions of the popliteus were compared from full extension to deep flexion using normosized, oversized, and undersized implants (one size increments).
RESULTS
At the tibia, TKA caused the popliteus to translate posteriorly, mostly in full extension: 4.1 ± 2 mm for normosized implants, and 15.8 ± 3 mm with oversized implants, but no translations were observed when using undersized implants. At the femur, TKA caused the popliteus to translate laterally at deeper flexion angles, peaking between 80° and 120°: 2 ± 0.4 mm for normosized implants and 2.6 ± 0.5 mm with oversized implants. Three-dimensional analysis revealed prosthetic overhang at the posterosuperior corner of normosized and oversized femoral components (respectively, up to 2.9 mm and 6.6 mm).
CONCLUSIONS
A well-sized tibial component modifies popliteal tracking, while an undersized tibial component maintains more physiologic patterns. Oversizing shifts the popliteus considerably throughout the full arc of motion. This study suggests that both femoro- and tibio-popliteus impingements could play a role in residual pain and stiffness after TKA.
Topics: Arthroplasty, Replacement, Knee; Cadaver; Humans; Joint Instability; Knee Joint; Knee Prosthesis; Ligaments, Articular; Postoperative Complications; Range of Motion, Articular; Tomography, X-Ray Computed
PubMed: 27671286
DOI: 10.1007/s00167-016-4330-8