Management of Painful Shoulder Arthroplasty: A Narrative Review

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Effect of aging on extracellular matrix and collagen turnover related pathways in human tendons and cultured human tenocytes

The aging process involves different organs, including the musculoskeletal system. Age-related modifications affecting the tendon such as reduced cell proliferation and decreased glycosaminoglycan and proteoglycan content were previously described, but data are incomplete and discordant. Therefore, aim of our study was to characterize the effect of aging on tendons, with particular attention to collagen turnover. For this purpose, tendons and cultured tenocytes were obtained by healthy young (age <65 years) and aging subjects (≥65 years), and analyzed by morphological and molecular methods. Our data show that aging tenocytes have a reduced proliferation rate. Haematoxylin and eosin, Sirius red and Alcian blue staining, respectively, revealed that tendon structure is maintained, and that collagen and proteoglycan content is similar in young and aging tendons. However, decreased lysyl hydroxylase 2b gene expression was observed in aging tenocytes, suggesting that differences in collagen maturation could be responsible for a decreased ability to resist mechanical loading. By fluorescence microscopy, actin cytoskeleton modifications such as fewer and shorter stress fibers were observed in some aging tenocytes, consistent with a decreased ability to form focal adhesions and, therefore, a reduced migration potential. Intermediate filaments and microtubules were not modified by aging. Considered as a whole, our results suggest that the structure of aged tendons is preserved, but the biomechanical properties could be impaired by reduced collagen cross-linking. Moreover, modifications of actin filaments could affect the mechanotransduction system allowing tenocytes to adapt their ability for extracellular matrix remodeling in response to mechanical loading. Therefore, aged tendons could be likely more prone to develop tendinopathies

Dynamic contact area ratio in shoulder instability: an innovative diagnostic technique measuring interplay of bony lesions

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The 3d body centre of mass trajectory before and after total knee arthroplasty:symmetry and mechanical work

The kinematics of walking on treadmill were collected and the 3D trajectory of the body centre of mass was computed in subjects suffering from mono-lateral knee osteoarthritis, before and after total knee arthroplasty. Experimental data showed after 6 months from surgery significant improvements in many biomechanical parameters as gait symmetry indices and total work done

The crucial questions on synovial biopsy: when, why, who, what, where, and how?

In the majority of joint diseases, changes in the organization of the synovial architecture appear early. Synovial tissue analysis might provide useful information for the diagnosis, especially in atypical and rare joint disorders, and might have a value in case of undifferentiated inflammatory arthritis, by improving disease classification. After patient selection, it is crucial to address the dialogue between the clinician and the pathologist for adequately handling the sample, allowing identifying histological patterns depending on the clinical suspicion. Moreover, synovial tissue analysis gives insight into disease progression helping patient stratification, by working as an actionable and mechanistic biomarker. Finally, it contributes to an understanding of joint disease pathogenesis holding promise for identifying new synovial biomarkers and developing new therapeutic strategies. All of the indications mentioned above are not so far from being investigated in everyday clinical practice in tertiary referral hospitals, thanks to the great feasibility and safety of old and more recent techniques such as ultrasound-guided needle biopsy and needle arthroscopy. Thus, even in rheumatology clinical practice, pathobiology might be a key component in the management and treatment decision-making process. This review aims to examine some essential and crucial points regarding why, when, where, and how to perform a synovial biopsy in clinical practice and research settings and what information you might expect after a proper patient selection

Distally based sural fasciomusculocutaneous flap for treatment of wounds of the distal third of the leg and ankle with exposed internal hardware

Soft tissue reconstruction of the distal third of the lower limb with exposure of the internal hardware is a challenging problem with several potential complications, such as exposure of the fracture line, fracture instability and bacterial contamination. The treatment of these lesions usually consists of substitution of the internal hardware with external fixation devices and further flap coverage. We propose a different reconstructive approach, characterized by harvesting a sural fasciomusculocutaneous flap on the exposed internal hardware once a sterile ground has been obtained. Four patients were retrospectively analyzed. Soft tissue reconstruction was achieved in all cases. In one case hardware removal was necessary for complete healing. The sural fasciomusculocutaneous flap is a safe alternative to other pedicled and free flaps. Moreover, it allows direct coverage of internal fixators, thus completing the reconstruction in less time. This flap fits best to the morphology of the wound and internal hardware, leaving the main vascular trunk of the leg intact and at the same time providing a reliable vascular supply

Reliability of forced internal rotation and active internal rotation to assess lateral instability of the biceps pulley

Purpose: the aim of this study was to investigate the relationship between positive painful forced internal rotation (FIR) and lateral pulley instability in the presence of a pre-diagnosed posterosuperior cuff tear. The same investigation was conducted for painful active internal rotation (AIR). Methods: a multicenter prospective study was conducted in a series of patients scheduled to undergo arthroscopic posterosuperior cuff repair. Pain was assessed using a visual analog scale (VAS) and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) was administered. The VAS score at rest, DASH score, and presence/absence of pain on FIR and AIR were recorded and their relationships with lesions of the lateral pulley, cuff tear patterns and shape of lesions were analyzed. Results: the study population consisted of 115 patients (mean age: 55.1 years) recruited from 12 centers. The dominant arm was affected in 72 cases (62.6%). The average anteroposterior extension of the lesion was 1.61 cm. The mean preoperative VAS and DASH scores were 6.1 and 41.8, respectively. FIR and AIR were positive in 94 (81.7%) and 85 (73.9%) cases, respectively. The lateral pulley was compromised in 50 cases (43.4%). Cuff tears were partial articular in 35 patients (30.4%), complete in 61 (53%), and partial bursal in 19 (16.5%). No statistical correlation between positive FIR or AIR and lateral pulley lesions was detected. Positive FIR and AIR were statistically associated with complete lesions. Negative FIR was associated with the presence of partial articular tears. Conclusions: painful FIR in the presence of a postero-superior cuff tear does not indicate lateral pulley instability. When a cuff tear is suspected, positive FIR and AIR are suggestive of full-thickness tear patterns while a negative FIR suggests a partial articular lesion. Level of evidence: level I, validating cohort study with good reference standards