1,720,975 research outputs found
Stem cells in articular cartilage regeneration
Full text linkMesenchymal stem cells (MSCs) have emerged as a promising option to treat articular defects and early osteoarthritis (OA) stages. However, both their potential and limitations for a clinical use remain controversial. Thus, the aim of this systematic review was to examine MSCs treatment strategies in clinical settings, in order to summarize the current evidence of their efficacy for the treatment of cartilage lesions and OA.Among the 60 selected studies, 7 were randomized, 13 comparative, 31 case series, and 9 case reports; 26 studies reported the results after injective administration, whereas 33 used surgical implantation. One study compared the two different modalities. With regard to the cell source, 20 studies concerned BMSCs, 17 ADSCs, 16 BMC, 5 PBSCs, 1 SDSCs, and 1 compared BMC versus PBSCs. Overall, despite the increasing literature on this topic, the evidence is still limited, in particular for high-level studies. On the other hand, the available studies allow to draw some indications. First, no major adverse events related to the treatment or to the cell harvest have been reported. Second, a clinical benefit of using MSCs therapies has been reported in most of the studies, regardless of cell source, indication, or administration method. This effectiveness has been reflected by clinical improvements and also positive MRI and macroscopic findings, whereas histologic features gave more controversial results among different studies. Third, young age, lower BMI, smaller lesion size for focal lesions, and earlier stages of OA joints have been shown to correlate with better outcomes, even though the available data strength does not allow to define clear cutoff values. Finally, definite trends can be observed with regard to the delivery method: currently cultured cells are mostly being administered by i.a. injection, while one-step surgical implantation is preferred for cell concentrates. In conclusion, while promising results have been shown, the potential of these treatments should be confirmed by reliable clinical data through double-blind, controlled, prospective and multicenter studies with longer follow-up, and specific studies should be designed to identify the best cell sources, manipulation, and delivery techniques, as well as pathology and disease phase indications
Anterior cruciate ligament reconstruction and rehabilitation: predictors of functional outcome
No full textSurgical reconstruction of an injured anterior cruciate ligament (ACL) leads to full recovery of function and sports activity in a high percentage of cases. The aim of the present study was to analyze variables related to the patient, the surgical technique and the post-surgical rehabilitation methods, seeking to identify predictors of outcome and recovery time after ACL reconstruction. One hundred and four patients (81 M, 23 F) undergoing a step-based rehabilitation protocol after ACL reconstruction were evaluated. 43.2% of them had an isolated ACL lesion, whereas 56.8% had one or more concurrent injuries. Data relating to personal characteristics, surgery and post-operative management were collected and analyzed for correlation. Clinical outcome was evaluated with IKDC subjective score and the Tegner score, and the time to reach full recovery was noted as well. Young patients with a higher pre-injury Tegner activity level or who practice sport at professional level, no concurrent capsular lesions and no postoperative knee bracing had better clinical results and took shorter time to recover. Also, a higher percentage of on-the-field rehabilitation sessions, and absence of significant muscle strength deficits at the first knee isokinetic test emerged as rehabilitation-related factors leading to a better post-surgical outcome. Personal, surgical and rehabilitation factors should be considered in order to optimize patient management and maximize the expected results. Further studies are needed to find the strongest factors in different patients
Arthroscopic mosaicplasty: Long-term outcome and joint degeneration progression.
Full text linkBACKGROUND:
This study aims to document the long-term results in a group of patients treated with arthroscopic mosaicplasty for knee cartilage lesions, both in terms of clinical outcome and joint degeneration progression, evaluated by radiographs.
METHODS:
26 patients (19 men and 7 women, mean age 29years, mean BMI 23) treated arthroscopically with mosaicplasty for cartilage defects of the femoral condyles (mean/median/mode size 1.9 standard deviation, SD 0.6cm2) were prospectively evaluated at 12years follow-up. The clinical outcome was analyzed with IKDC and Tegner scores. Range of motion, transpatellar and suprapatellar circumferences were also measured. Radiographs with weight-bearing antero-posterior and Rosenberg projections were used for radiological evaluation in 18 patients, applying both Kellgren-Lawrence score and a direct joint line measurement to assess osteoarthritis.
RESULTS:
A significant improvement in all clinical scores was obtained from the basal evaluation to the 12-year follow-up (IKDC subjective score from 36.8 standard deviation, SD 13.0 to 77.3 standard deviation, SD 20.6, P<0.0005; Tegner score from 2.9 standard deviation, SD 1.3 to 5.2 standard deviation, SD 2.5, P<0.0005), and better results in patients with a higher pre-injury activity level and those requiring fewer plugs. The radiographic evaluation showed significantly poorer Kellgren-Lawrence scores and a reduction of the joint line in the treated compartments. Knees with 3-4 plugs presented a significantly higher joint degeneration level with respect to those implanted with 1-2 plugs.
CONCLUSIONS:
Mosaicplasty is an effective surgical option for small lesions of the femoral condyles. Although joint degeneration progression was present at 12years, this did not affect significantly the clinical outcome which was satisfactory at long-term follow-up
Meniscal Scaffolds - Preclinical Evidence to Support their Use: A Systematic Review
No full textArthroscopic meniscal treatment is the most common procedure performed in the orthopedic practice. Current management of meniscal pathology relies on different therapeutic options, ranging from selective meniscectomy, suturing, and to meniscal replacement by using either allografts or scaffolds. The progresses made in the field of regenerative medicine and biomaterials allowed to develop several meniscal substitutes, some of those currently used in the clinical practice. Before reaching the clinical application, these devices necessarily undergo accurate testing in the animal model: the aim of the present manuscript is to systematically review the scientific evidence derived by animal model results for the use of meniscal scaffolds, in order to understand the current state of research in this particular field and to identify the trends at preclinical level that may influence in the near future the clinical practice. Thirty-four papers were included in the present analysis. In 12 cases the meniscal scaffolds were used with cells to further stimulate tissue regeneration. With the exception of some negative reports regarding dacron-based scaffolds, the majority of the trials highlighted that biomaterials and bio-engineered scaffolds are safe and could play a beneficial role in stimulating meniscal healing and in chondral protection. With regard to the benefits of cell augmentation, the evidence is limited to a small number of studies and no conclusive evidence is available. However, preclinical evidence seems to suggest that cells could enhance tissue regeneration with respect to the use of biomaterials alone, and further research should confirm the translational potential of cell-based approach
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Higher failure rate of secondary patellar resurfacing following bicompartmental knee arthroplasty
No full textIntroductionThe role of secondary patellar resurfacing (SPR) in anterior knee pain (AKP) is still debated in literature. A regional arthroplasty registry was investigated, aiming to: (1) assess the survival rate of SPR; and (2) compare SPR to tricompartmental TKA.Materials and methodsThe regional arthroplasty registry RIPO was investigated about all SPRs performed after bicompartmental arthroplasty. The survival rates and the reasons for revision were assessed as any other factor that could have influenced implants failure. SPR survivorship was compared to tricompartmental TKAs.Results406 SPRs performed after bicompartmental arthroplasty were analyzed. The survival rates were 80.6% (CI 95% 75.9-84.5) at 5 years and 77.6% (CI 95% 72.4-82) at 7 years. Half of the SPRs was performed 0.9-2.4 years after the index bicompartmental arthroplasty. SPR achieved lower survival than tricompartmental TKA (80.6% vs 96.7%, p < 0.001), with an adjusted hazard ratio for failure of 5.5 (CI 95% 4.2-7.1, p < 0.001). SPRs performed within 2 years after primary implant had a significantly higher rates of failure when compared to tricompartmental TKA (HR: 6.4, CI 95% 4.8-8.4, p < 0.001).ConclusionSPR after bicompartmental knee arthroplasty showed modest 5- and 7-year survival rates, worse than primary tricompartmental TKA. When SPRs are performed within 2 years after primary arthroplasty, a significant higher risk of failure should be expected, highlighting than appropriate pre-operative work-up and patient selection is crucial for SPR successful outcome
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