Martin Anthony Birchall

Volumetric muscle loss (VML) refers to the loss of skeletal muscle that exceeds intrinsic repair and heals with fibrosis, poor perfusion and denervation. Conventional treatments such as muscle grafts and decellularized matrices improve structure but rarely restore normal strength or limb use. Hydrogels have emerged as injectable scaffolds that fill irregular defects, deliver cells and cues and better match muscle-like mechanics. This review summarizes hydrogels for VML repair, including natural and semi-synthetic systems (gelatin, collagen, hyaluronan, fibrin, alginate, muscle-derived decellularized extracellular matrix (ECM)), synthetic networks and peptide-based hydrogels. Natural matrices provide tissue-derived signals but offer limited control over stiffness and degradation. Synthetic hydrogels allow precise tuning of mechanics and porosity but require additional ligands and growth factors to effectively support VML repair. Peptide hydrogels self-assemble into ECM-like nanofibres and can display multiple motifs for adhesion, immunomodulation, angiogenesis and neurotrophic support, although direct VML data remain sparse. Across these material classes, we highlight shared design principles: aligned architectures and hierarchical porosity, graded properties at muscle–tendon and muscle–nerve interfaces and degradation and cue delivery matched to overlapping healing phases, combined with appropriate cell strategies. Together, these concepts support a shift from passive defect filling towards reconstruction of a regenerative niche with hybrid hydrogel constructs for VML repair.

Wearable silent speech systems hold significant potential for restoring communication in patients with speech impairments. However, seamless, coherent speech remains elusive, and clinical efficacy is still unproven. Here, we present an AI-driven intelligent throat (IT) system that integrates throat muscle vibrations and carotid pulse signal sensors with large language model (LLM) processing to enable fluent, emotionally expressive communication. The system utilizes ultrasensitive textile strain sensors to capture high-quality signals from the neck area and supports token-level processing for real-time, continuous speech decoding, enabling seamless, delay-free communication. In tests with five stroke patients with dysarthria, IT’s LLM agents intelligently corrected token errors and enriched sentence-level emotional and logical coherence, achieving low error rates (4.2% word error rate, 2.9% sentence error rate) and a 55% increase in user satisfaction. This work establishes a portable, intuitive communication platform for patients with dysarthria with the potential to be applied broadly across different neurological conditions and in multi-language support systems.

Pathologies affecting the respiratory system can lead to a debilitating decrease in quality of life and can be fatal. To test medical devices and implants for the human respiratory system, a simulation system that can reproduce multiple respiratory features is necessary. Currently available respiratory simulators only focus on reproducing flow rate profiles of breathing while coughing simulators focus on aerosol analysis. In this paper we propose a novel, bioinspired robotic simulator that can physically replicate both breathing and coughing flow rate characteristics of healthy adults. We conducted a study on 31 healthy adult participants to gather the flow rate measurement of normal breathing, deep breathing, breathing while running and coughing. Coughing flow rate profiles vary considerably between participants, making an accurate simulation of coughs a challenge. To enable cough flow rate simulation, a new methodology based on the identification of four cough phases, Attack, Decay, Sustain and Release (ADSR) and their parametrization was devised. This methodology leads to the unprecedented ability to reproduce diverse and complex coughing flow rate profiles. Our simulator is able to reproduce respiratory flows with a root mean square error (RMSE) of 1.8 L/min between normal participant breathing and its simulation, 5% of the maximum flow rate simulated for that participant (pMFR), an RMSE of 10.08 L/min for deep breathing, 18% of the pMFR and an RMSE of 13.29 L/min for exertion breathing, 17% of pMFR. For the simulation of an average cough we recorded an RMSE of 51.43 L/min, 13% of the pMFR and for a low flow rate cough an RMSE of 12.38 L/min, 9.5% of the pMFR. The presented simulator matches the fundamentals of human breathing and coughing, advancing the current capability of respiratory system simulators.

Objective This study aimed to characterise the laryngological presentations of Ehlers-Danlos syndrome and conduct a preliminary exploration of patient-reported outcome measures. Methods This paper describes a retrospective case series of patients with Ehlers-Danlos syndrome seen by the senior author between 2005 and 2019. A literature review was conducted to summarise the existing findings. Results Twenty-one patients met the inclusion criteria. All reported symptoms were grouped; this showed that swallowing, voice and hyolaryngeal skeletal complex problems were commonest. Patient-reported outcome measures were available for eight patients, which showed large variations in: the Reflux Severity Index (median = 25.5; range = 0-33), Eating Assessment Tool score (median = 21.5; range = 0-35) and Voice Handicap Index (median = 21.5; range = 0-104). Twelve studies met our literature review inclusion criteria, involving at least 91 patients with laryngological presentations of Ehlers-Danlos syndrome. Conclusion Ehlers-Danlos syndrome patients experience musculoskeletal issues, which in the throat manifest as hyolaryngeal skeletal complex problems. Future studies with larger patient numbers are required to validate laryngological patient-reported outcome measure tools in Ehlers-Danlos syndrome.

Total laryngectomy (TL) affects critical functions such as swallowing, coughing and speaking. An artificial, bioengineered larynx (ABL), operated via myoelectric signals, may improve quality of life for TL patients. To evaluate the efficacy of using surface electromyography (sEMG) as a control signal to predict instances of swallowing, coughing and speaking, sEMG was recorded from submental, intercostal and diaphragm muscles. The cohort included TL and control participants. Swallowing, coughing, speaking and movement actions were recorded, and a range of classifiers were investigated for prediction of these actions. Our algorithm achieved F1-scores of 76.0 ± 4.4% (swallows), 93.8 ± 2.8% (coughs) and 70.5 ± 5.4% (speech) for controls, and 67.7 ± 4.4% (swallows), 71.0 ± 9.1% (coughs) and 78.0 ± 3.8% (speech) for TLs, using a random forest (RF) classifier. 75.1 ± 6.9% of swallows were detected within 500 ms of onset in the controls, and 63.1 ± 6.1% in TLs. sEMG can be used to predict critical larynx movements, although a viable ABL requires improvements. Results are particularly encouraging as they encompass a TL cohort. An ABL could alleviate many challenges faced by laryngectomees. This study represents a promising step toward realising such a device.

Current methods to replace damaged upper airway epithelium with exogenous cells are limited. Existing strategies use grafts that lack mucociliary function, leading to infection and the retention of secretions and keratin debris. Strategies that regenerate airway epithelium with mucociliary function are clearly desirable and would enable new treatments for complex airway disease.Here, we investigated the influence of the extracellular matrix (ECM) on airway epithelial cell adherence, proliferation and mucociliary function in the context of bioengineered mucosal grafts.In vitro, primary human bronchial epithelial cells (HBECs) adhered most readily to collagen IV. Biological, biomimetic and synthetic scaffolds were compared in terms of their ECM protein content and airway epithelial cell adherence.Collagen IV and laminin were preserved on the surface of decellularised dermis and epithelial cell attachment to decellularised dermis was greater than to the biomimetic or synthetic alternatives tested. Blocking epithelial integrin α2 led to decreased adherence to collagen IV and to decellularised dermis scaffolds. At air–liquid interface (ALI), bronchial epithelial cells cultured on decellularised dermis scaffolds formed a differentiated respiratory epithelium with mucociliary function. Usingin vivochick chorioallantoic membrane (CAM), rabbit airway and immunocompromised mouse models, we showed short-term preservation of the cell layer following transplantation.Our results demonstrate the feasibility of generating HBEC grafts on clinically applicable decellularised dermis scaffolds and identify matrix proteins and integrins important for this process. The long-term survivability of pre-differentiated epithelia and the relative merits of this approach against transplanting basal cells should be assessed further in pre-clinical airway transplantation models.

We present two cases of coronavirus disease 2019 (COVID-19)-related laryngotracheitis in good-prognosis, ventilated patients who had failed extubation. As the pandemic continues to unfold across the globe and better management of those with respiratory failure develops, this may be an increasingly common scenario. Close ENT-intensivist liaison, meticulous team preparation, early consideration of rigid endoscopy and prospective data collection and case sharing are recommended.