Clinical outcome of latissimus dorsi tendon transfer and partial cuff repair in irreparable postero-superior rotator cuff tear

Background and purpose Irreparable rotator cuff tears are a common cause of pain in adult population, requiring in many cases a surgical treatment. Possible alternatives are debridement, partial repair, muscle transfers and joint replacement. We evaluated two groups of patients with irreparable rotator cuff tear treated surgically: one group received an arthroscopic-assisted latissimus dorsi tendon transfer (LDTT), and the other an arthroscopic rotator cuff partial repair. Aim of our study was to compare clinical results and quality of life in two groups of patients with massive irreparable rotator cuff tear: one receiving an arthroscopic LDTT and the other receiving an arthroscopic rotator cuff partial repair. Methods Forty patients were assigned to two groups: 20 patients to group TT treated with LDTT and 20 patients to group PR treated with a partial repair. The average follow-up duration was 2.8 years (1\u20135, SD 3). Pre- and postoperative modified UCLA shoulder score, ROM, measurement of the strength and the rotator cuff quality of life (RC-QOL) were used to asses the outcome. Results LDTT showed significative improvements when compared to partial repair in UCLA score results, strength and RC-QOL questionnaire. No differences were found between the groups in pain relief. Conclusion Both techniques are effective in reducing patients\u2019 symptoms. We believe that in younger, high-demanding patients with no or mild osteoarthritis, the LDTT represents a valid treatment option with better modified UCLA score improvement and strength at our follow-up

Revision reverse shoulder arthroplasty in failed shoulder arthroplasties for rotator cuff deficiency

PURPOSE: the aim of this systematic literature review is to report clinical outcomes of reverse shoulder arthroplasty (RSA) used as a revision surgery following failure of the primary implant due to rotator cuff insufficiency. METHODS: a systematic review was performed using the following key words: revision, shoulder, rotator cuff deficiency, outcome assessment, treatment outcome, complications. Studies eligible for inclusion in the review were clinical trials investigating patients in whom a primary shoulder arthroplasty implant with an incompetent rotator cuff was replaced with a reverse shoulder prosthesis. RESULTS: nine articles were identified and further reviewed. The results refer to a total of 226 shoulders that were treated with RSA as revision surgery. The patients in the studies had a mean age ranging from 64 to 72 years and the longest follow-up was 3.8 years. Improvements in function and reduction of pain were shown by many studies, but the mean Constant score ranged from 44.2 to 56. High complication rates (of up to 62%) were recorded, and a mean reoperation rate of 27.5%. CONCLUSIONS: RSA as revision surgery for patients with rotator cuff deficiency is a valid option, and often the only solution available, but it should be limited to elderly patients with poor function and severe pain. LEVEL OF EVIDENCE: level IV, systematic review of level I-IV studies

Regenerative Medicine in Rotator Cuff Injuries

Rotator cuff injuries are a common source of shoulder pathology and result in an important decrease in quality of patient life. Given the frequency of these injuries, as well as the relatively poor result of surgical intervention, it is not surprising that new and innovative strategies like tissue engineering have become more appealing. Tissue-engineering strategies involve the use of cells and/or bioactive factors to promote tendon regeneration via natural processes. The ability of numerous growth factors to affect tendon healing has been extensively analyzed in vitro and in animal models, showing promising results. Platelet-rich plasma (PRP) is a whole blood fraction which contains several growth factors. Controlled clinical studies using different autologous PRP formulations have provided controversial results. However, favourable structural healing rates have been observed for surgical repair of small and medium rotator cuff tears. Cell-based approaches have also been suggested to enhance tendon healing. Bone marrow is a well known source of mesenchymal stem cells (MSCs). Recently, ex vivo human studies have isolated and cultured distinct populations of MSCs from rotator cuff tendons, long head of the biceps tendon, subacromial bursa, and glenohumeral synovia. Stem cells therapies represent a novel frontier in the management of rotator cuff disease that required further basic and clinical research

Repair versus shaving of partial-thickness articular-sided tears of the upper subscapularis tendon : a prospective randomized controlled trial

Purpose: The purpose of this study was to evaluate whether treating partial-thickness articular-sided tears of the upper subscapularis (ssC) tendon with a dedicated suture anchor would result in an internal rotation strength improvement compared with simple shaving of the ssC tendon and footprint. Methods: Twenty-six patients with a limited ssC tendon tear (equal or inferior to the most superior centimeter) in association with a posterosuperior cuff lesion were prospectively randomized to two treatments: repair with a dedicated suture anchor versus shaving of the tendon and footprint. the patients also underwent long head of the biceps (LHB) treatment and posterosuperior cuff tear repair. in each patient the following parameters were measured both preoperatively and at a minimum follow-up of 2.5 years: strength in internal rotation in the bear-hug testing position (using a digital tensiometer), DAsH score and Constant scores. MRi assessment of tendon healing was performed at the final follow-up. Results: Twenty of the 26 patients (76%) were reviewed after a mean follow-up time of 42 months: 11 patients had undergone ssC tendon repair and nine simple shaving. At final follow-up no significant differences were found between the repaired and shaving group in strength in internal rotation (9.5 \ub1 3.8 kg versus 10.3\ub15.4 kg; p=0.7). the DAsH score and Constant score also failed to show significant differences between the two groups. Furthermore, no significant difference in ssC tendon healing rate was observed on MRi evaluation. Conclusions: Partial-thickness articular-sided tear of the upper ssC tendon in association with a posterosuperior rotator cuff repair and LHB treatment, when limited to the superior centimeter of the ssC tendon, shows a comparable performance in terms of strength in internal rotation either after simple shaving or a tendon-to-bone repair. Level of evidence: Level II, prospective comparative study

Autologous Microfragmented Adipose Tissue Reduces the Catabolic and Fibrosis Response in an in Vitro Model of Tendon Cell Inflammation

Background. Mesenchymal stem cells (MSCs) emerged as a promising therapy for tendon pathologies. Microfragmented adipose tissue (\u3bcFAT) represents a convenient autologous product for the application of MSC-based therapies in the clinical setting. In the present study, the ability of \u3bcFAT to counteract inflammatory processes induced by IL-1\u3b2 on human tendon cells (TCs) was evaluated. Methods. Cell viability and proliferation were evaluated after 48 hours of transwell coculture of TCs and autologous \u3bcFAT in the presence or absence of IL-1\u3b2. Gene expression of scleraxis, collagen type I and type III, metalloproteinases-1 and -3, and cyclooxygenase-2 was evaluated by real-time RT-PCR. The content of VEGF, IL-1Ra, TNF\u3b1, and IL-6 was evaluated by ELISA. Results. IL-1\u3b2-treated TCs showed augmented collagen type III, metalloproteases, and cyclooxygenase-2 expression. \u3bcFAT was able to reduce the expression of collagen type III and metalloproteases-1 in a significant manner, and at the same time, it enhanced the production of VEGF, IL-1Ra, and IL-6. Conclusions. In this in vitro model of tendon cell inflammation, the paracrine action of \u3bcFAT, exerted by anti-inflammatory molecules and growth factors, was able to inhibit the expression of fibrosis and catabolic markers. Then, these results suggest that the application of \u3bcFAT may represent an effective conservative or adjuvant therapy for the treatment of tendon disorders

Lipogems product treatment increases the proliferation rate of human tendon stem cells without affecting their stemness and differentiation capability

Increasing the success rate of rotator cuff healing remains tremendous challenge. Among many approaches, the possibility of activating resident stem cells in situ, without the need to isolate them from biopsies, could represent valuable therapeutic strategy. Along this line, it has been recently demonstrated that lipoaspirate product, Lipogems, contains and produces growth-factors that may activate resident stem cells. In this study, human tendon stem cells (hTSCs) from the rotator cuff were cocultured in a transwell system with the Lipogems lipoaspirate product and compared to control untreated cells in terms of cell proliferation, morphology, stem cell marker and VEGF expression, and differentiation and migration capabilities. Results showed that the Lipogems product significantly increases the proliferation rate of hTSCs without altering their stemness and differentiation capability. Moreover, treated cells increase the expression of VEGF, which is crucial for the neovascularization of the tissue during the healing process. Overall, this study supports that directly activating hTSCs with the Lipogems lipoaspirate could represent a new practical therapeutic approach. In fact, obtaining a lipoaspirate is easier, safer, and more cost-effective than harvesting cells from tendon or bone marrow biopsies, expanding them in GMP facility and then reinjecting them in the patient

Reporting rotator cuff tears on magnetic resonance arthrography using the Snyder's arthroscopic classification

AIM: To determine diagnostic performance of magnetic resonance arthrography (MRA) in evaluating rotator cuff tears (RCTs) using Snyder's classification for reporting. METHODS: One hundred and twenty-six patients (64 males, 62 females; median age 55 years) underwent shoulder MRA and arthroscopy, which represented our reference standard. Surgical arthroscopic reports were reviewed and the reported Snyder's classification was recorded. MRA examinations were evaluated by two independent radiologists (14 and 5 years' experience) using Snyder's classification system, blinded to arthroscopy. Agreement between arthroscopy and MRA on partial- and full-thickness tears was calculated, first regardless of their extent. Then, analysis took into account also the extent of the tear. Interobserver agreement was also calculated the quadratically-weighted Cohen kappa statistics. RESULTS: On arthroscopy, 71/126 patients (56%) had a full-thickness RCT. The remaining 55/126 patients (44%) had a partial-thickness RCT. Regardless of tear extent, out of 71 patients with arthroscopically-confirmed full-thickness RCTs, 66 (93%) were correctly scored by both readers. All 55 patients with arthroscopic diagnosis of partial-thickness RCT were correctly assigned as having a partial-thickness RCT at MRA by both readers. Interobserver reproducibility analysis showed total agreement between the two readers in distinguishing partial-thickness from full-thickness RCTs, regardless of tear extent (k = 1.000). With regard to tear extent, in patients in whom a complete tear was correctly diagnosed, correct tear extent was detected in 61/66 cases (92%); in the remaining 5/66 cases (8%), tear extent was underestimated. Agreement was k = 0.955. Interobserver agreement was total (k = 1.000). CONCLUSION: MRA shows high diagnostic accuracy and reproducibility in evaluating RCTs using the Snyder's classification for reporting. Snyder's classification may be adopted for routine reporting of MRA

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the "hypoxic niches" present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue

Effects of the pulsed electromagnetic field PST® on human tendon stem cells : A controlled laboratory study

Background: Current clinical procedures for rotator cuff tears need to be improved, as a high rate of failure is still observed. Therefore, new approaches have been attempted to stimulate self-regeneration, including biophysical stimulation modalities, such as low-frequency pulsed electromagnetic fields, which are alternative and non-invasive methods that seem to produce satisfying therapeutic effects. While little is known about their mechanism of action, it has been speculated that they may act on resident stem cells. Thus, the purpose of this study was to evaluate the effects of a pulsed electromagnetic field (PST\uae) on human tendon stem cells (hTSCs) in order to elucidate the possible mechanism of the observed therapeutic effects. Methods: hTSCs from the rotator cuff were isolated from tendon biopsies and cultured in vitro. Then, cells were exposed to a 1-h PST\uae treatment and compared to control untreated cells in terms of cell morphology, proliferation, viability, migration, and stem cell marker expression. Results: Exposure of hTSCs to PST\uae did not cause any significant changes in proliferation, viability, migration, and morphology. Instead, while stem cell marker expression significantly decreased in control cells during cell culturing, PST\uae-treated cells did not have a significant reduction of the same markers. Conclusions: While PST\uae did not have significant effects on hTSCs proliferation, the treatment had beneficial effects on stem cell marker expression, as treated cells maintained a higher expression of these markers during culturing. These results support the notion that PST\uae treatment may increase the patient stem cell regenerative potential

Controls on natural gas migration in the western Nile Delta fan

The aim of this study is to combine petrophysical and geochemical data in order to reconstruct the migration history and pathways of mixed microbial-thermogenic gases drilled on the Nile Delta fan, offshore Egypt. While general interest lies in understanding migration routes, rates and mechanisms special attention is dedicated to understanding (1) the origin of gas in both reservoir and non-reservoir units using chemical and isotopic fingerprints and (2) whether a free gas phase supports relatively rapid leakage via bulk flow in non-reservoir units, both above and below commercial accumulations. The Pilocene section in this study is a classic slope environment comprising channels, mud-rich turbidites, mass transport complexes and hemipelagites. Data from seismic and drilled wells suggest that the channel and levee reservoirs are rarely full to spill, implying either a lack of charge and leakage rates which precludes complete filling of the structures. The provided data set enables a quantitative assessment of gas distribution and its genetic fingerprint in the context of both stratigraphic position and lithology. Data is reported from 25 wells, each provided with a conventional wireline log suite and some with borehole images and high-quality core images. Gas concentration data, plus compositional and isotope data are available for isotubes and headspace gas for both reservoir and non-reservoir units. Small-to-medium scale linear and non-linear depth shifts between different techniques (core recovery, core logging, wireline logging) in conjunction with scale and resolution issues demanded logical/stochastic depth synchronisation and well as harmonisation of signal resolution (typically up-scaling). Accordingly, great care was taken to depth-match core, log and gas data. In general, there is evidence of leaking thermogenic and partly biodegraded gas from the reservoirs under investigation, while some microbial methane appears to be retained in the cap rock. Careful assessment of the maturity of the thermogenic gas charge suggests that in a given structure, maturities are similar throughout the sampled section of underseal, reservoir and top seal. Furthermore, compositional temperature stratification suggests a balance between influx of fresh gas and microbial metabolism rates, supporting the concept of a dynamic charge-leak scenario that is sustaining hydrocarbon fermenting microbial communities in the deep biosphere. It was found that microbial recycling of hydrocarbons at depth enables the identification of diffusive gas mixing pathways in the combined analysis of methane and ethane compositional and isotopic data. The proposed diffusion pattern supports the idea of a widely present coupling between both methanogenic and biodegrading microbial communities that exhibit strong carbon isotopic dis-balances at gas-water contacts (GWC) where nutrient supply is in favour of the biodegrading metabolism. Although the hypothesis of coupled diffusive/microbial gas overprints complies with (1) various literature reports that microbial attack on free gas phases is hindered by restricted physical access and (2) segregative isotope fractionation as a consequence of differences on methane and ethane diffusivity, it is conditional to the nature of gas mixing patterns along borehole trajectories in the context of lithology and pore fluid saturations. Undoubtedly, the ubiquitous presence of microbial gas has consequences for vertical net leakage. As classic empirical wireline models for hydrocarbon saturation (i.e. free gas phase volumetrics) are not suited for clay-dominated cap rock sections, an alternative approach presented in this study is based on total gas (TG) modelling from nuclear logs and its solubility in the formation of brine. The calibrated saturation model is scale-independent and implies that free gas occurs on the most of the clay-dominated non-reservoir sections. However, model resolution is not sufficient to capture the suspected filamentary network of free gas phase within the mudrock pore space that enables relatively rapid leakage via Darcy flow. In an unique attempt to validate manual and thereby subjective lithofacies allocations to core images a subset of rock sample properties such as grain size fractions and porosity were successfully modelled using quantitative core image properties. However, model validity appears to be restricted to clay-rich lithofacies due to both an absence of calibration data for sands and occurrence of abnormally dark sandstone units. Further, an artificial neural network (ANN) was trained to propagate the calibrated core fancies along the entire wireline logged borehole section to set the lithological context for a detailed fluid flow analysis. Reproducibility of input (core) facies by output (wireline) facies is similar to the reproducibility by fellow geoscientists but could not be significantly improved to 60-80% of reliability by reduction of facies types. The study shows that a combination of geochemical data with lithological and petro-physical information generates detailed insights into rates, mechanisms, and pathways of two phase flow through the deep biosphere of gas-charged basins. Vertical, geologically rapid flow through mud-rich sequences is a viable migration route for gas if the influence of cap rock bypass systems (permeable faults, sandstone intrusions, mud volcanoes etc.) is restricted. It was found that an adequate quantification of both thermogenic gas fraction and diffusive gas mixing fingerprints is crucial to identity stratigraphic intervals that are not dominated by advective leakage through the pore space and are consequently bypassed.EThOS - Electronic Theses Online ServiceGBUnited Kingdo