Integrating cryo-OrbiSIMS with computational modelling and metadynamics simulations enhances RNA structure prediction at atomic resolution.

The 3D architecture of RNAs governs their molecular interactions, chemical reactions, and biological functions. However, a large number of RNAs and their protein complexes remain poorly understood due to the limitations of conventional structural biology techniques in deciphering their complex structures and dynamic interactions. To address this limitation, we have benchmarked an integrated approach that combines cryogenic OrbiSIMS, a state-of-the-art solid-state mass spectrometry technique, with computational methods for modelling RNA structures at atomic resolution with enhanced precision. Furthermore, using 7SK RNP as a test case, we have successfully determined the full 3D structure of a native RNA in its apo, native and disease-remodelled states, which offers insights into the structural interactions and plasticity of the 7SK complex within these states. Overall, our study establishes cryo-OrbiSIMS as a valuable tool in the field of RNA structural biology as it enables the study of challenging, native RNA systems.

Comparing outcomes of the anterosuperior and deltopectoral approaches in reverse total shoulder arthroplasty for degenerative glenohumeral arthritis: a systematic review.

PURPOSE: Reverse total shoulder replacement (rTSR) improves pain and function in patients with a wide range of shoulder pathology. Anterosuperior (AS) and deltopectoral (DP) approaches are widely used to gain access to the glenohumeral joint in arthroplasty. Our aim was to systematically review the literature comparing outcomes of these two approaches when performing rTSR for degenerative glenohumeral arthritis. METHODS: Systematic review was performed with an electronic multi-database search (Pubmed, Medline & Embase) according to PRISMA guidelines on 18th September 2022. Data from published studies of any study design that met the inclusion criteria were extracted, reviewed and synthesized. RESULTS: A total of 38 studies were identified for full text review, of which four were included. No significant difference in pain and range of motion were observed between approaches. Scapular notching was more common in the anterosuperior approach. Low rates of instability and intra-operative fracture were observed in both. CONCLUSION: Both approaches demonstrate similar clinical outcomes with reference to pain, range of motion and complications when performing rTSR indicated for degenerative joint disease. However, further well-designed studies are required.

Open Subpectoral Tenodesis for Isolated Traumatic Long Head of Biceps Tendon Rupture Provides Excellent Functional Outcomes in Active Male Patients.

BACKGROUND:  For many years the long head of biceps tendon (LHBT) rupture has been described and is commonly identified by weakness, cramping, and the so-called "Popeye" sign. Traditionally, this was treated non-operatively, likely reflecting patient factors and the technical difficulty in reattaching a degenerative and shortened tendon. In contrast, traumatic distal biceps rupture is now commonly repaired despite historically being managed non-operatively. The advent of a convenient and reproducible surgical technique led to an increase in the rate of fixation, thereby improving the cramping and weakness associated with non-operative treatment. Given recent surgical advances within this field, many techniques are now present for LHBT pathology. We describe results from a cohort of patients suffering traumatic LHBT rupture who sought a surgical solution to improve their symptoms. METHODS:  Over four years, 18 male patients underwent surgical intervention for isolated traumatic LHBT rupture. The technique used involved an open subpectoral tenodesis with fixation of the LHBT into the bicipital groove. Postoperative immobilization using a sling was recommended for six weeks prior to a progressive rehabilitation program. Patients were assessed with pre- and postoperative visual analog scores (VAS) for pain and American Shoulder and Elbow Society (ASES) scores. RESULTS: The mean patient age at the time of surgery was 49 years (range: 26-65 years). The mean time to surgery was nine weeks (range: 2-24 weeks). All patients showed an improvement following surgery with a mean pre-op ASES score of 33 (range: 10-60) compared to a post-op score of 92.6 (range: 85-100). All patients were able to return to work and sport, with all but one returning to the same functional demand level of work. The mean pre-op pain VAS was 6.3 (out of 10) compared to 0.2 post-op. All patients had a requirement for analgesia pre-operatively and none had postoperatively. No surgical complications were observed. No correlation was observed between the time to surgery and the outcome. DISCUSSION:  LHBT rupture is often treated non-operatively as few studies within the literature describe the surgical technique and outcomes from surgical intervention. When treated non-operatively, patients complain of pain, cramping, and cosmetic deformity known as the "Popeye" sign. Following a traumatic rupture of the LHBT, we have demonstrated excellent outcomes using a standard approach and common fixation technique that has the potential to improve the functional outcome for symptomatic patients. CONCLUSION:  Open subpectoral biceps tenodesis is associated with excellent outcomes in symptomatic patients following isolated LHBT rupture.