Quadriceps neuromuscular function remains impaired in the short- and long-term following knee arthroscopy for meniscal surgery and/or anterior cruciate ligament (ACL) reconstruction. The aim of this ...study was to compare quadriceps neuromuscular impairments in patients following meniscal surgery with and without ACL reconstruction. Thirty patients were tested six months after meniscal surgery with (
= 15) and without (
= 15) ACL reconstruction. We bilaterally assessed knee extension maximal voluntary contraction (MVC) torque using dynamometry, vastus lateralis thickness using ultrasound, quadriceps voluntary activation and evoked knee extension torque with transcutaneous electrical stimulation. Patient-reported outcomes were evaluated with the Knee Injury and Osteoarthritis Outcome Score (KOOS). Compared with meniscus patients, ACL patients demonstrated larger asymmetries in MVC torque (15% vs. 5%,
= 0.049) and vastus lateralis thickness (6% vs. 0%,
= 0.021). In ACL patients, asymmetries in MVC torque correlated with asymmetries in evoked torque (
= 0.622,
= 0.013). In meniscus patients, asymmetries in muscle activation correlated with KOOS quality of life (
= 0.619,
= 0.018). Patients demonstrated persistent quadriceps muscle weakness six months after ACL reconstruction, but not after isolated meniscal surgery. Quantitative and/or qualitative muscular changes likely underlie quadriceps muscle weakness in ACL patients, whereas activation failure is associated with poor quality of life in some meniscus patients.
Abstract Patella baja is a severe complication seen after trauma, prolonged immobilization and surgery. Several surgical methods have been described to proximalize the patella without a change in the ...patella tendon length. Yet, patella tendon shortening and thickening can be regarded as the hallmark pathology. As such, we describe a technique for the lengthening of the patellar tendon to pathoconformly address underlying patella baja. The technique is reproducible and gives the possibility of an early postoperative mobilization to prevent re-baja—a typical complication after patella baja surgery.
Background:
Physiological 0.9% saline is commonly used as an irrigation fluid in modern arthroscopy. There is a growing body of evidence that a hyperosmolar saline solution has chondroprotective ...effects, especially if iatrogenic injury occurs.
Purpose:
To (1) corroborate the superiority of a hyperosmolar saline solution regarding chondrocyte survival after mechanical injury and (2) observe the modulatory response of articular cartilage to osmotic stress and injury.
Study Design:
Controlled laboratory study.
Methods:
Osteochondral explants were isolated from bovine stifle joints and exposed to either 0.9% saline (308 mOsm) or hyperosmolar saline (600 mOsm) and then damaged with a sharp dermatome blade to attain a confined full-thickness cartilage injury site, incubated in the same fluids for another 3 hours, and transferred to chondropermissive medium for further culture for 1 week. Chondrocyte survival was assessed by confocal imaging, while the cellular response was evaluated over 1 week by relative gene expression for apoptotic and inflammatory markers and mediator release into the medium.
Results:
The full-thickness cartilage cut resulted in a confined zone of cell death that mainly affected superficial zone chondrocytes. Injured samples that were exposed to hyperosmolar saline showed less expansion of cell death in both the axial (P < .007) and the coronal (P < .004) plane. There was no progression of cell death during the following week of culture. Histological assessment revealed an intact cartilage matrix and normal chondrocyte morphology. Inflammatory and proapoptotic genes were upregulated on the first days postexposure with a notable downregulation toward day 7. Mediator release into the medium was concentrated on day 3.
Conclusion:
This in vitro cartilage injury model provides further evidence for the chondroprotective effect of a hyperosmolar saline irrigation fluid, as well as novel data on the capability of articular cartilage to quickly regain joint homeostasis after osmotic stress and injury.
Clinical Relevance:
Raising the osmolarity of an irrigating solution may be a simple and safe strategy to protect articular cartilage during arthroscopic surgery.
Objective. Osteoarthritis is a long-term complication of acute articular infections. However, the roles of cartilage and synovia in this process are not yet fully understood. Methods. Patients with ...acute joint infections were enrolled in a prospective clinical trial and the cytokine composition of effusions compared in patients with arthroplasty (n = 8) or with intact joints (n = 67). Cytokines and cell function were also analyzed using a human in vitro model of joint infection. Results. Synovial IL-1β levels were significantly higher in patients with arthroplasty (p = 0.004). Higher IL-1β concentrations were also found in the in vitro model without chondrocytes (p < 0.05). The anti-inflammatory cytokines IL-4 and IL-10 were consistently expressed in vivo and in vitro, showing no association with the presence of cartilage or chondrocytes. In contrast, FasL levels increased steadily in vitro, reaching higher levels without chondrocytes (p < 0.05). Likewise, the viability of synovial fibroblasts (SFB) during infection was higher in the presence of chondrocytes. The cartilage-metabolism markers aggrecan and bFGF were at higher concentrations in intact joints, but also synthesized by SFB. Conclusions. Our data suggest an anti-inflammatory effect of cartilage associated with the SFBs’ increased resistance to infections, which displayed the ability to effectively synthesize cartilage metabolites.The trial is registered with DRKS 00003536, MISSinG.
Abstract Matrix-assisted chondrocyte transplantation (m-ACI) still lacks any standardization in its execution in terms of cell passage (P), cell yield (C) and in vitro membrane-holding time (T). It ...was the goal of this study to analyze the effect of shifting cell culture parameters (P, C, T) on the in vitro as well as in vivo effort of a regulated animal m-ACI. Autologous rabbit knee articular chondrocytes were seeded within bilayer collagen I/III 3-D matrices in variation of P, C and T. Each time, 2 PCT-identical by 2 PCT-identical cell-matrix-constructs (CMC)/animal were created. Simultaneously 2 (PCT-distinct) were re-implanted (CMC-e) autologous into artificial trochlear pristine chondral defects in vivo to remain for 12 weeks while the remaining 2 were harvested (CMC-i) for immediate in vitro analysis at the time of transplantation of their identical twins. mRNA of both, CMC-e regenerates and CMC-i membranes, was analyzed for Collagen-1,-2,-10, COMP, Aggrecan, Sox9 expression by use of a mixed linear model, multiple regression analysis. Generally, CMC-i values were higher than CMC-e values for differentiation targets; the opposite was true for dedifferentiation targets. Regarding individual gene expression, in vivo regenerate cell-matrix properties were significantly dependent on initial cell-matrix in vitro values as a sign of linearity. The parameter membrane-holding time (T) had strongest effects on the resulting mRNA expression with slightly less impact of the parameter passage (P), whereas cell yield (C) had clearly less effects. Noting differences between in vitro and in vivo data, in general, optimal expression patterns concerning chondrogenic differentiation were achieved by few passages, medium cellular yield, short membrane-holding time. Clinical m-ACI may benefit from optimal orchestration of the cell culture parameters passage, yield and time.
Abstract
Background
Communication in healthcare has been extensively studied, but most research has focused on miscommunication and the importance of communication for patient safety. Previous ...research on interprofessional communication has mainly focused on relationships between physicians and nurses in non-psychiatric settings. Since communication is one of the core competencies in psychiatric care, more research on interprofessional communication between other clinicians is needed, and should be explored from a broader perspective. This study aimed to explore and describe interprofessional communication in a psychiatric outpatient unit.
Method
During spring 2022, data consisting of over 100 h of fieldwork were collected from observations, formal semi-structured interviews and informal conversations inspired by the focused ethnography method. Data was collected at an outpatient unit in central Sweden, and various clinicians participated in the study. The data analysis was a back-and-forth process between initial codes and emerging themes, but also cyclical as the data analysis process was ongoing and repeated and took place simultaneously with the data collection.
Results
We found that a workplace’s history, clinicians´ workload, responsibilities and hierarchies influence interprofessional communication. The results showed that the prerequisites for interprofessional communication were created through the unit’s code of conduct, clear and engaging leadership, and trust in the ability of the various clinicians to perform new tasks.
Conclusion
Our results indicate that leadership, an involving working style, and an environment where speaking up is encouraged and valued can foster interprofessional communication and respect for each other´s professional roles is key to achieving this. Interprofessional communication between different clinicians is an important part of psychiatric outpatient work, where efficiency, insufficient staffing and long patient queues are commonplace. Research can help shed light on these parts by highlighting aspects influencing communication.
The long-range transport of persistent organic pollutants (POPs) is investigated with two multimedia box models of the global system. ChemRange is a purely evaluative, one-dimensional steady-state ...(level III) model; CliMoChem is a two-dimensional model with different temperatures, land/water ratios and vegetation types in different latitudinal zones. Model results are presented for three case studies: (i) the effect of atmospheric aerosol particles on the long-range transport of POPs, (ii) the effect of oceanic deposition on the long-range transport of different PCB congeners, (iii) the global fractionation of different PCB congeners. The model results for these case studies show: (i) the low atmospheric half-lives estimated for several organochlorine pesticides are likely to be inconsistent with the observed long-range transport of these compounds; (ii) export to the deep sea reduces the potential for long-range transport of highly hydrophobic compounds (but does not remove these chemicals from the biosphere); (iii) there are different meanings of the term global fractionation that refer to different aspects of the fractionation process and need to be distinguished. The case-study results further indicate that the influences of varying environmental conditions on the physicochemical properties and the degradation rate constants of POPs need to be determined.
Multimedia box models are applied to case studies of the behavior of POPs.
Debonding of the acetabular cartilage is a characteristic type of hip damage found in cam-type femoroacetabular impingement (FAI), which remains a treatment challenge. In addition to resection, ...refixation of these flaps using fibrin sealants has been recently suggested. However, there is only limited evidence available that the proposed refixation method results in sufficient viable cartilage formation to ensure long-term flap grafting and restored tissue function.
To determine the flap tissue characteristics that would justify refixation of delaminated chondral flaps with a fibrin sealant, we characterized (1) the extracellular matrix (ECM) of chondral flaps in terms of chondrocyte viability and distribution of ECM components and (2) the chondrogenic potential of resident cells to migrate into fibrin and produce a cartilaginous matrix.
Ten acetabular chondral flaps and three non-delaminated control cartilage samples were resected during surgery. Chondrocyte viability was quantified using a live-dead assay. To assess the ECM, histological staining of glycosaminoglycans, collagen II, and collagen I allowed the qualitative study of their distribution. The ability of chondrocytes to migrate out of the ECM was tested by encapsulating minced flap cartilage in fibrin gels and semi-quantitatively assessing the projected area of the gel covered with migrating cells. The potential of chondrocytes to produce a cartilaginous matrix was studied with a pellet assay, a standard three-dimensional culture system to test chondrogenesis. Positive controls were pellets of knee chondrocytes of age-matched donors, which we found in a previous study to have a good capacity to produce cartilage matrix. Statistical significance of controlled quantitative assays was determined by the Student's t-test with Welch's correction.
The proportion of viable chondrocytes in flaps was lower than in nondelaminated cartilage (50% ± 19% versus 76 ± 6%; p = 0.02). Histology showed a disrupted ECM in flaps compared with nondelaminated controls, with the presence of fibrillation, a loss of glycosaminoglycan at the delaminated edge, collagen II throughout the whole thickness of the flap, and some collagen I-positive area in two samples. The resident chondrocytes migrated out of this disrupted ECM in all tested samples. However in pellet culture, cells isolated from the flaps showed a qualitatively lower chondrogenic potential compared with positive controls, with a clearly inhomogeneous cell and matrix distribution and an overall smaller projected area (0.4 versus 0.7 mm; p = 0.038).
Despite the presence of viable chondrocytes with migration potential, the cells resided in a structurally altered ECM and had limited capacity to deposit ECM, leading us to question their capacity to produce sufficient ECM within the fibrin sealant for stable long-term attachment of such flaps.
The characterization of delaminated cartilage in cam FAI patients suggests that the refixation strategy might be adversely influenced by the low level of ECM produced by the residing cells.
Current climate models often predict fractional cloud cover on the basis of a diagnostic probability density function (PDF) describing the subgrid‐scale variability of the total water specific ...humidity, qt, favouring schemes with limited complexity. Standard shapes are uniform or triangular PDFs, the widths of which are assumed to scale with the grid‐box mean qt or the grid‐box mean saturation specific humidity, qs. In this study, the qt variability is analysed from large‐eddy simulations for two stratocumulus, two shallow cumulus, and one deep convective cases. We find that, in most cases, triangles are a better approximation to the simulated PDFs than uniform distributions. In 2 of the 24 slices examined, the actual distributions were so strongly skewed that the simple symmetric shapes could not capture the PDF at all. The distribution width for either shape scales acceptably well with both the mean values of qt and qs, the former being a slightly better choice. The qt variance is underestimated by the fitted PDFs, but overestimated by the existing parametrizations. While the cloud fraction is in general relatively well diagnosed from fitted or parametrized uniform or triangular PDFs, it fails to capture cases with small partial cloudiness, and in 10–30% of the cases misdiagnoses clouds in clear skies or vice versa. The results suggest choosing a parametrization with a triangular shape, where the distribution width would scale with the grid‐box mean qt using a scaling factor of 0.076. However, this is subject to the caveat that the reference simulations examined here were partly for rather small domains and driven by idealised boundary conditions.
Background:
Currently, no clinical midterm results have been reported on arthroscopically assisted reduction of the acutely dislocated acromioclavicular (AC) joint using suture-button devices for ...fixation.
Hypothesis:
Athroscopically assisted reduction of the acutely dislocated AC joint yields satisfactory clinical outcomes without loss of reduction, clavicle migration, or AC joint degeneration at midterm follow-up evaluation.
Study Design:
Case series; Level of evidence, 4.
Methods:
The clinical and radiographic outcomes of 23 of 30 consecutive patients (21 men, 2 women) who underwent anatomic reduction for acute AC joint dislocation using 2 suture-button devices between 2006 and 2007 were reviewed. Radiographic evaluation was performed by measurement of coracoclavicular (CC) distance and AC displacement. Clinical evaluation included a visual analog scale (VAS) for pain, the Constant score, the simple shoulder test, and the Short Form–36. Previously, this same patient collective was reviewed after 2 years of follow-up using similar methods.
Results:
All 23 patients were available for midterm follow-up examination 58 months postoperatively. There were 3 Rockwood type III, 3 type IV, and 17 type V acromioclavicular joint separations. Mean ± SD follow-up was 58 ± 5.6 months (range, 51-67 months). Most patients (96%) remained very satisfied or satisfied with the procedure outcome. The VAS and Constant score improved significantly when compared with baseline (0.3 ± 0.6 and 91.5 ± 4.7 at 58 months postoperatively vs 4.5 ± 1.9 and 34.5 ± 6.9 at baseline) and remained essentially unchanged when compared with the 2-year outcome scores (0.3 ± 0.6 and 91.5 ± 4.7 at 58 months postoperatively vs 0.25 ± 0.5 and 94.3 ± 3.2 at 2 years). Radiographs showed 8 radiographic failures (undercorrection, posterior displacement, or both) and 4 additional overcorrections of the CC distance. When comparing with 24-month data, 17 of 20 radiographs remained unchanged; 1 case of previous overcorrection drifted into normal AC alignment and 2 cases increased in posterior subluxation of the clavicle.
Conclusion:
Arthroscopically assisted reduction of the acutely dislocated AC joint provides satisfactory clinical results 58 months after surgery. Compared with the baseline, all patients improved significantly. Two of 23 patients revealed an increased posterior dislocation compared with evaluation 24 months after surgery. No further migration of the clavicle or AC joint degeneration was observed.
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