Advances in Engineered Three-Dimensional (3D) Body Articulation Unit Models.

Indeed, the body articulation units, commonly referred to as body joints, play significant roles in the musculoskeletal system, enabling body flexibility. Nevertheless, these articulation units suffer from several pathological conditions, such as osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis, gout, and psoriatic arthritis. There exist several treatment modalities based on the utilization of anti-inflammatory and analgesic drugs, which can reduce or control the pathophysiological symptoms. Despite the success, these treatment modalities suffer from major shortcomings of enormous cost and poor recovery, limiting their applicability and requiring promising strategies. To address these limitations, several engineering strategies have been emerged as promising solutions in fabricating the body articulation as unit models towards local articulation repair for tissue regeneration and high-throughput screening for drug development. In this article, we present challenges related to the selection of biomaterials (natural and synthetic sources), construction of 3D articulation models (scaffold-free, scaffold-based, and organ-on-a-chip), architectural designs (microfluidics, bioprinting, electrospinning, and biomineralization), and the type of culture conditions (growth factors and active peptides). Then, we emphasize the applicability of these articulation units for emerging biomedical applications of drug screening and tissue repair/regeneration. In conclusion, we put forward the challenges and difficulties for the further clinical application of the in vitro 3D articulation unit models in terms of the long-term high activity of the models.

Moderate to Substantial Inter-Rater Reliability in the Assessment of Cranial Bone Mobility Restrictions.

Background: The World Health Organization benchmarks for osteopathic training consider cranial osteopathy as an important manual skill. Studies of cranial manual therapy have exhibited poor reliability. The aim of this study was to investigate the inter-rater reliability of the manual mobility tests of the spheno-occipital synchondrosis (SOS), and the temporal, parietal, and frontal bones, as assessed in osteopathic manual therapy. Methods: Twenty-one adults were assessed on a single day by three experienced osteopaths using a standard assessment protocol. Before data collection, the osteopaths participated in a consensus training, which included establishing the criteria for identifying a cranial bone mobility restriction; the application of the seven-step palpation method; a pretesting practice; a fine-tuning palpation training; and a calibration period before the assessment of the subjects. Three subjects were assessed simultaneously with the evaluators rotating to assess each subject. The evaluators were blinded to the subject by a curtain, and each other's assessments. Each bone was rated as restricted or not restricted. The authors applied the Landis and Koch classification to describe the magnitude of inter-rater reliability. Results: Moderate reliability was established for a lateral strain of the SOS (Fleiss' generalized kappa 0.48), substantial reliability was established for the other SOS strain patterns (Fleiss' generalized kappa 0.62-0.75), and almost perfect reliability for temporal, parietal, and frontal bone (Fleiss' generalized kappa 0.81-0.96). Conclusion: The results demonstrate consistency when three experienced osteopaths evaluate cranial bone mobility restrictions. The results highlight the importance of consensus training and rigorous methodology in manual therapy reliability studies.

Acoustic pre-stimulation modulates startle and postural reactions during sudden release of standing support surface in aging.

Falls contribute to injuries and reduced level of physical activity in older adults. During falls, the abrupt sensation of moving downward triggers a startle-like reaction that may interfere with protective response movements necessary to maintain balance. Startle reaction could be dampened by sensory pre-stimulation delivered immediately before a startling stimulus. This study investigated the neuromodulatory effects of pre-stimulation on postural/startle responses to drop perturbations of the standing support surface in relation to age. Ten younger and 10 older adults stood quietly on an elevated computer-controlled moveable platform. At an unpredictable time, participants were dropped vertically to elicit a startle-like response. Reactive drop perturbation trials without a pre-stimulus (control) were alternated with trials with acoustic pre-stimulus tone (PSI). A two-way mixed design analysis of variance comparing condition (control vs. PSI) X group (younger vs. older) was performed to analyze changes in muscle activation patterns, ground reaction force, and joint angular displacements. Compared to younger adults, older adults showed lower neck muscle electromyography amplitude reduction rate and incidence of response. Peak muscle activation in neck, upper arm, and hamstring muscles were reduced during PSI trials compared to control trials in both groups (p < 0.05). In addition, knee and hip joint flexion prior to ground contact was reduced in PSI trials compared to control (p < 0.05). During post-landing balance recovery, increased knee and hip flexion displacement and time to peak impact force were observed in PSI trials compared to control condition (p < 0.05). PSI reduced startle-induced muscle activation at proximal body segments and likely decreased joint flexion during abrupt downward vertical displacement perturbations of the body. Older adults retained the ability to modulate startle and postural responses but their neuromodulatory capacity was reduced compared with younger adults. Further research on the potential of applying PSI as a possible therapeutic tool to reduce the risk of fall-related injury is needed.

Context-dependent limb movement encoding in neuronal populations of motor cortex.

Neuronal networks of the mammalian motor cortex (M1) are important for dexterous control of limb joints. Yet it remains unclear how encoding of joint movement in M1 depends on varying environmental contexts. Using calcium imaging we measured neuronal activity in layer 2/3 of the M1 forelimb region while mice grasped regularly or irregularly spaced ladder rungs during locomotion. We found that population coding of forelimb joint movements is sparse and varies according to the flexibility demanded from individual joints in the regular and irregular context, even for equivalent grasping actions across conditions. This context-dependence of M1 encoding emerged during task learning, fostering higher precision of grasping actions, but broke apart upon silencing of projections from secondary motor cortex (M2). These findings suggest that M1 exploits information from M2 to adapt encoding of joint movements to the flexibility demands of distinct familiar contexts, thereby increasing the accuracy of motor output.

The roles of musical expertise and sensory feedback in beat keeping and joint action.

Auditory feedback of actions provides additional information about the timing of one's own actions and those of others. However, little is known about how musicians and nonmusicians integrate auditory feedback from multiple sources to regulate their own timing or to (intentionally or unintentionally) coordinate with a partner. We examined how musical expertise modulates the role of auditory feedback in a two-person synchronization-continuation tapping task. Pairs of individuals were instructed to tap at a rate indicated by an initial metronome cue in all four auditory feedback conditions: no feedback, self-feedback (cannot hear their partner), other feedback (cannot hear themselves), or full feedback (both self and other). Participants within a pair were either both musically trained (musicians), both untrained (nonmusicians), or one musically trained and one untrained (mixed). Results demonstrated that all three pair types spontaneously synchronized with their partner when receiving other or full feedback. Moreover, all pair types were better at maintaining the metronome rate with self-feedback than with no feedback. Musician pairs better maintained the metronome rate when receiving other feedback than when receiving no feedback; in contrast, nonmusician pairs were worse when receiving other or full feedback compared to no feedback. Both members of mixed pairs maintained the metronome rate better in the other and full feedback conditions than in the no feedback condition, similar to musician pairs. Overall, nonmusicians benefited from musicians' expertise without negatively influencing musicians' ability to maintain the tapping rate. One implication is that nonmusicians may improve their beat-keeping abilities by performing tasks with musically skilled individuals.

Baicalin Attenuates Joint Pain and Muscle Dysfunction by Inhibiting Muscular Oxidative Stress in an Experimental Osteoarthritis Rat Model.

Osteoarthritis (OA) is the most common degenerative joint disease, and causes major pain and disability in adults. It has been reported that muscle weakness and inflammation contribute to osteoarthritis development and progression. Oxidative stress plays important roles in muscle dysfunction and inflammation in osteomyelitis. Baicalin, the major active constituent of the isolated root of Scutellarialateriflora Georgi, has been shown to have anti-oxidative and anti-inflammatory effects. In this study, we evaluated the potential effects of baicalin on osteoarthritis. We established experimental osteoarthritis rat model, applied baicalin to the rats, and then explored the potential protective effect of baicalin on osteoarthritis severity, muscle dysfunction, and oxidative stress. Baicalin alleviated severity of OA in rats. Baicalin application attenuated muscle dysfunction in OA rats by increasing citrate synthase activity, myosin heavy chain IIa expression, and decreasing interleukin 6 production. Baicalin decreased muscular reactive oxygen species generation in OA rats. Baicalin inhibited nuclear factor erythroid-derived 2-like 2 expression in OA rats. Baicalin attenuated osteoarthritis in rat by inhibiting oxidative stress.

Human ossicular-joint flexibility transforms the peak amplitude and width of impulsive acoustic stimuli.

The role of the ossicular joints in the mammalian middle ear is still debated. This work tests the hypothesis that the two synovial joints filter potentially damaging impulsive stimuli by transforming both the peak amplitude and width of these impulses before they reach the cochlea. The three-dimensional (3D) velocity along the ossicular chain in unaltered cadaveric human temporal bones (N = 9), stimulated with acoustic impulses, is measured in the time domain using a Polytec (Waldbronn, Germany) CLV-3D laser Doppler vibrometer. The measurements are repeated after fusing one or both of the ossicular joints with dental cement. Sound transmission is characterized by measuring the amplitude, width, and delay of the impulsive velocity profile as it travels from the eardrum to the cochlea. On average, fusing both ossicular joints causes the stapes velocity amplitude and width to change by a factor of 1.77 (p = 0.0057) and 0.78 (p = 0.011), respectively. Fusing just the incudomalleolar joint has a larger effect on amplitude (a factor of 2.37), while fusing just the incudostapedial joint decreases the stapes velocity on average. The 3D motion of the ossicles is altered by fusing the joints. Finally, the ability of current computational models to predict this behavior is also evaluated.

Ultrasound study of elbow ulnar collateral ligament changes in collegiate baseball players: A pilot study.

OBJECTIVE: To assess changes in elbow ulnar collateral ligament length in college baseball pitchers over the course of a single season. DESIGN: Cohort Feasibility Study. METHODS: Diagnostic ultrasound was used to assess both the dominant and non-dominant medial elbow joint space in four pitchers and five fielders and compared to in-game pitching data. Shoulder, elbow, wrist, hip, knee, and ankle range of motion measurements were also taken. RESULTS: Mean trends for both the pitching and fielding groups showed no increases in dominant arm medial elbow joint space. Range of motion (ROM) increases were seen in both groups, and neither ultrasound nor ROM changes correlated to number of pitches thrown. CONCLUSION: It is feasible that shoulder and hip range of motion changes directly affect stresses at the elbow in baseball pitching (Wilk et al., 2014) (Sauers et al., 2014). Further research is needed to investigate whether UCL injuries are related to increased laxity of the ligament.

Control of Redundant Kinematic Degrees of Freedom in a Closed-Loop Brain-Machine Interface.

Brain-machine interface (BMI) systems use signals acquired from the brain to directly control the movement of an actuator, such as a computer cursor or a robotic arm, with the goal of restoring motor function lost due to injury or disease of the nervous system. In BMIs with kinematically redundant actuators, the combination of the task goals and the system under neural control can allow for many equally optimal task solutions. The extent to which kinematically redundant degrees of freedom (DOFs) in a BMI system may be under direct neural control is unknown. To address this question, a Kalman filter was used to decode single- and multi-unit cortical neural activity of two macaque monkeys into the joint velocities of a virtual four-link kinematic chain. Subjects completed movements of the chain's endpoint to instructed target locations within a two-dimensional plane. This system was kinematically redundant for an endpoint movement task, as four DOFs were used to manipulate the 2-D endpoint position. Both subjects successfully performed the task and improved with practice by producing faster endpoint velocity control signals. Kinematic redundancy allowed null movements whereby the individual links of the chain could move in a way that cancels out and does not result in endpoint movement. As the subjects became more proficient at controlling the chain, the amount of null movement also increased. Task performance suffered when the links of the kinematic chain were hidden and only the endpoint was visible. Furthermore, all four DOFs of the joint-velocity control space exhibited task-relevant modulation. The relative usage of each DOF depended on the configuration of the chain, and trials in which the less-prominent DOFs were utilized also had better task performance. Overall, these results indicate that the subjects incorporated the redundant components of the control space into their control strategy. Future BMI systems with kinematic redundancy, such as exoskeletal systems or anthropomorphic robotic arms, may benefit from allowing neural control over redundant configuration dimensions as well as the end-effector.

Glorisa superba Hydroalcoholic Extract from Tubers Attenuates Experimental Arthritis by Downregulating Inflammatory Mediators, and Phosphorylation of ERK/JNK/p-38.

Glorisa superba (GS) is a medicinal plant that has been traditionally used in the treatment of joint pain and rheumatoid arthritis (RA). The present study was carried out to investigate the antiarthritic activity of Glorisa superba hydroalcoholic extract (GSHE) in an adjuvant-induced arthritis (AIA) rat model. Arthritis was induced by sub-plantar administration of complete Freund's adjuvant (CFA) and GSHE (25, 50, or 100 mg/kg/day) was administered orally for 21 consecutive days. Joint diameter was measured on Days 0, 3, 7, 14, and 21. GSHE dose dependently attenuates the increased joint diameter and serum tumor necrosis factor (TNF)-α level following induction of arthritis by adjuvant. This attenuation was well substantiated with reduced mRNA expression of interleukin (IL)-1ß, IL-6, TNF-α, and NF-κB. Additionally, GSHE inhibited phosphorylation of the mitogen-activated protein kinases (MAPK) signaling pathway as there was decreased protein expression of MAPK (p-p38/p38 and p-ERK/ERK p-JNK/JNK ratio). Moreover, GSHE in a dose-dependent fashion normalized the redox status of ankle joint (GSH, malonaldialdehyde [MDA], and NO levels and superoxide dismutase [SOD] and catalase [CAT] activities) and displayed decreased inflammatory cell infiltration in histopathological findings. Taken together, these findings indicate that GSHE protects against AIA by modulating MAPK.

[An overview of the beneficial effects of hydrolysed collagen intake on joint and bone health and on skin ageing]. / REVISIÓN DE LOS EFECTOS BENEFICIOSOS DE LA INGESTA DE COLÁGENO HIDROLIZADO SOBRE LA SALUD OSTEOARTICULAR Y EL ENVEJECIMIENTO DÉRMICO.

INTRODUCTION: Hydrolysate Collagen (HC) consists of small peptides with a molecular weight lower than 5.000 Da. produced from gelatinization and subsequent enzymatic hydrolysis of native collagen which is found in rich collagenic animal tissues. There is much evidence about the HC ingestion positive effect over degenerative joint and bones diseases. OBJECTIVE: The aim of this article is to review the present scientific studies about HC and to evaluate the HC ingestion therapeutical effects on some collagenic tissues as cartilage, bones and skin. RESULTS: Up to date, there are more than 60 scientific studies (in vitro, in vivo, clinics and on bioavailability) about HC ingestion efficacy on reducing collagen damage and loss consequences as joint pain and erosion (osteoarthritis), bone density loss (osteoporosis) and skin ageing. CONCLUSIONS: Preclinical studies show that HC stimulates collagenic tissue regeneration by increasing not only collagen synthesis but minor components (glycosaminoglycans and hyaluronic acid) synthesis as well. Clinical studies show that HC continual ingestion helps to reduce and prevent joint pain, bone density loss and skin ageing. These results as well as its high level of tolerance and safety make HC ingestion attractive for a long-term use in bone and joint degenerative diseases and in fight against skin ageing.

Introducción: el colágeno hidrolizado (CH) es una mezcla de péptidos de colágeno con un peso molecular (PM) inferior a 5.000 Da. Se obtiene de la gelatinización y posterior hidrólisis enzimática de colágeno nativo procedente de tejidos animales ricos en esta proteína. Existe abundante evidencia científica sobre el efecto positivo que la toma de CH ejerce sobre las patologías osteoarticulares degenerativas y el envejecimiento dérmico. Objetivo: revisar los estudios científicos existentes actualmente sobre el CH y evaluar su acción terapéutica sobre algunos tejidos colaginosos como cartílagos, huesos y piel. Resultados: hasta la fecha se han realizado más de 60 estudios científicos (in vitro, in vivo, clínicos y de biodisponibilidad) sobre la efectividad del CH a la hora de reducir las consecuencias del deterioro y pérdida de colágeno tisular como son el dolor y el desgaste articular (artrosis), la pérdida de masa ósea (osteoporosis) y el envejecimiento dérmico. Conclusiones: los estudios preclínicos indican que el CH estimula la regeneración de los tejidos colaginosos, potenciando la síntesis de colágeno tisular y también de los restantes componentes minoritarios de dichos tejidos (proteoglicanos y ácido hialurónico). Los estudios clínicos demuestran que la ingesta continuada de CH ayuda a reducir el dolor articular de desgaste, a ralentizar la pérdida de masa ósea y a atenuar los signos de envejecimiento dérmico. Estos resultados, junto con su alto nivel de seguridad y tolerancia, hacen del CH un suplemento adecuado para tomar a largo plazo, indicado para prevenir y tratar enfermedades crónicas degenerativas (artrosis y osteoporosis), así como para prevenir y atenuar el envejecimiento dérmico.

Observation of the clinical effects of iontophoresis of a chinese drug in the treatment of degenerative osteoarthropathy.

Degenerative osteoarthropathy, a kind of arthrosis induced by various factors, mainly affects articular cartilage and causes syndesmophyte formation. Its morbidity increases year by year, tending to occur more among young people than previously. This paper mainly discusses the clinical effects of iontophoresis of the Chinese drug in treating degenerative osteoarthropathy. A total of 296 cases of degenerative osteoarthropathy were randomly divided into two groups (of both genders): the iontophoresis group: the joint was treated with iontophoresis of the Chinese drug and a medium frequency electrotherapy instrument; the frequency electrotherapy group: the joint was treated only by medium frequency electrotherapy. The two groups were both treated for 30 min once a day, for a total of 4 weeks. The results of the study showed that, the total effective rate in the medium frequency electrotherapy group was 74.3%, the iontophoresis group was 93.2%, indicating the curative effect of iontophoresis of the Chinese medicine. The above finding indicates that, iontophoresis has a good clinical effect in the treatment of osteoarthropathy and deserves to be promoted and applied.

Perform kicking with or without jumping: joint coordination and kinetic differences between Taekwondo back kicks and jumping back kicks.

We investigated joint coordination differences between Taekwondo back kicks and jumping back kicks, and how jumping (in performing the latter) would alter engaging ground reaction forces (GRF) in executing kicking. Ten skilful athletes volunteered to perform both kinds of kicking within the shortest time for three successful trials. Three high-speed cameras and two force platforms were used for data collection, and the trial with the shortest execution time was selected for analysis. Movements were divided into the rotation and attack phases. With comparable execution time and maximum joint linear/angular speeds, back kicks and jumping back kicks differ mainly in larger GRF in the latter, and in greater target acceleration in the former probably because the support leg prevented athletes' rebounding after impact. In addition, more prominent antiphase and in-phase coordination between the shoulder segment and knee joint, and elongated rotation phase were found in jumping back kicks. Larger GRF values in jumping back kicks were generated for jump take-off rather than for a more powerful attack. In back kicks although the support leg remained ground contact, greatly decreased GRF in the attack phase suggested that the support leg mainly served as a rotation axis.

Assessment of Multi-Joint Coordination and Adaptation in Standing Balance: A Novel Device and System Identification Technique.

The ankles and hips play an important role in maintaining standing balance and the coordination between joints adapts with task and conditions, like the disturbance magnitude and type, and changes with age. Assessment of multi-joint coordination requires the application of multiple continuous and independent disturbances and closed loop system identification techniques (CLSIT). This paper presents a novel device, the double inverted pendulum perturbator (DIPP), which can apply disturbing forces at the hip level and between the shoulder blades. In addition to the disturbances, the device can provide force fields to study adaptation of multi-joint coordination. The performance of the DIPP and a novel CLSIT was assessed by identifying a system with known mechanical properties and model simulations. A double inverted pendulum was successfully identified, while force fields were able to keep the pendulum upright. The estimated dynamics were similar as the theoretical derived dynamics. The DIPP has a sufficient bandwidth of 7 Hz to identify multi-joint coordination dynamics. An experiment with human subjects where a stabilizing force field was rendered at the hip (1500 N/m), showed that subjects adapt by lowering their control actions around the ankles. The stiffness from upper and lower segment motion to ankle torque dropped with 30% and 48%, respectively. Our methods allow to study (pathological) changes in multi-joint coordination as well as adaptive capacity to maintain standing balance.

Effects of short-term resistance training and pulsed electromagnetic fields on bone metabolism and joint function in severe haemophilia A patients with osteoporosis: a randomized controlled trial.

OBJECTIVES: To assess the effects of short-term resistance training and pulsed electromagnetic fields on bone metabolism and joint function in patients with haemophilia with osteoporosis. DESIGN: A randomized, controlled, patient and blood sample assessor-blinded, six-week trial, three times weekly. SETTING: Hospital outpatients with severe haemophilia A and osteoporosis. SUBJECTS: Forty-eight patients were randomly assigned to resistance training (RT, n = 13), combined resistance training with pulsed electromagnetic fields (RTPEMF, n = 12), pulsed electromagnetic fields (PEMF, n = 11) and control (n = 12) groups. INTERVENTION: The RT group received 30-40 minutes of resistance exercises and placebo pulsed electromagnetic fields. The RTPEMF group received the same exercises with lower repetition and 30 minutes of pulsed electromagnetic fields. The PEMF group was exposed to 60 minutes of pulsed electromagnetic fields (30 Hz and 40 Gauss). MAIN MEASURES: Bone-specific alkaline phosphatase, N-terminal telopeptide of type 1 collagen, and joint function, using the modified Colorado Questionnaire, were measured before and after the programme. RESULTS: The absolute change of bone-specific alkaline phosphatase was significant in the RT and RTPEMF groups compared with the control group (25.41 ± 14.40, 15.09 ± 5.51, and -4.73 ± 2.93 U/L, respectively). The absolute changes in the total score for joint function were significant for knees, ankles, and elbows in the RT group (9.2 ± 1.38, 5.1 ± 0.5, and 3.2 ± 0.8, respectively) and the RTPEMF group (7.7 ± 1.0, 3.3 ± 0.6, and 2.5 ± 0.7, respectively) compared to the PEMF and control groups. This value was significant for knee joints in the PEMF group compared to the control group (3.4 ± 0.5 and 0.66 ± 0.4, respectively). CONCLUSIONS: Resistance training is effective for improving bone formation and joint function in severe haemophilia A patients with osteoporosis.

The plastic nature of the human bone-periodontal ligament-tooth fibrous joint.

This study investigates bony protrusions within a narrowed periodontal ligament space (PDL-space) of a human bone-PDL-tooth fibrous joint by mapping structural, biochemical, and mechanical heterogeneity. Higher resolution structural characterization was achieved via complementary atomic force microscopy (AFM), nano-transmission X-ray microscopy (nano-TXM), and microtomography (MicroXCT™). Structural heterogeneity was correlated to biochemical and elemental composition, illustrated via histochemistry and microprobe X-ray fluorescence analysis (µ-XRF), and mechanical heterogeneity evaluated by AFM-based nanoindentation. Results demonstrated that the narrowed PDL-space was due to invasion of bundle bone (BB) into PDL-space. Protruded BB had a wider range with higher elastic modulus values (2-8GPa) compared to lamellar bone (0.8-6GPa), and increased quantities of Ca, P and Zn as revealed by µ-XRF. Interestingly, the hygroscopic 10-30µm interface between protruded BB and lamellar bone exhibited higher X-ray attenuation similar to cement lines and lamellae within bone. Localization of the small leucine rich proteoglycan biglycan (BGN) responsible for mineralization was observed at the PDL-bone interface and around the osteocyte lacunae. Based on these results, it can be argued that the LB-BB interface was the original site of PDL attachment, and that the genesis of protruded BB identified as protrusions occurred as a result of shift in strain. We emphasize the importance of bony protrusions within the context of organ function and that additional study is warranted.

The effect of increased stiffness of the incudostapedial joint on the transmission of air-conducted sound by the human middle ear.

OBJECTIVE: To study the possible effects of increased stiffness at the incudostapedial joint (ISJ) on sound transmission in the human middle ear. BACKGROUND: The physiologic role played by the IS joint in the mechanics of human middle ear function is unclear. It is also unclear how fixation of this joint might manifest itself and what the implications are of fixing this joint during surgical reconstruction. HYPOTHESIS: Increased stiffness of the ISJ will affect sound transmission through the middle ear. METHODS: Cyanoacrylate adhesive was instilled around the ISJ joint in 5 fresh human cadaveric temporal bones to increase ISJ stiffness. Laser Doppler vibrometry measurements of sound-induced peak-to-peak displacement of the umbo and stapes footplate were made before and after stiffening the ISJ. RESULTS: At baseline, the measurements at the stapes footplate followed those at the umbo but were approximately 12 dB lower in the speech frequencies. We found that stiffening the ISJ produced an almost equal decrease in peak-to-peak displacement at both the umbo and the stapes footplate, with little change in their relative motion, consistent with an increase in ossicular impedance. The decrease was mainly between 400 and 1,000 Hz with a statistically significant mean magnitude loss of 6 dB at 740 Hz. CONCLUSION: Increased stiffness at the ISJ results in a small, probably clinically insignificant decrease of 3 to 6 dB in middle ear sound transmission in the lower frequencies between 400 and 1,000 Hz.

Physiological effects of oral glucosamine on joint health: current status and consensus on future research priorities.

The aim of this paper was to provide an overview of the current knowledge and understanding of the potential beneficial physiological effects of glucosamine (GlcN) on joint health. The objective was to reach a consensus on four critical questions and to provide recommendations for future research priorities. To this end, nine scientists from Europe and the United States were selected according to their expertise in this particular field and were invited to participate in the Hohenheim conference held in August 2011. Each expert was asked to address a question that had previously been posed by the chairman of the conference. Based on a systematic review of the literature and the collection of recent data, the experts documented the effects of GlcN on cartilage ageing, metabolic/kinetic and maintenance of joint health as well as reduction of risk of OA development. After extensive debate and discussion the expert panel addressed each question and a general consensus statement was developed, agreeing on the current state-of-the-art and future areas for basic and clinical studies. This paper summarizes the available evidence for beneficial effects of GlcN on joint health and proposes new insight into the design of future clinical trials aimed at identifying beneficial physiological effect of GlcN on joint tissues.