Body sensor networks: smart monitoring solutions after reconstructive surgery

Advances in reconstructive surgery are providing treatment options in the face of major trauma and cancer. Body Sensor Networks (BSN) have the potential to offer smart solutions to a range of clinical challenges. The aim of this thesis was to review the current state of the art devices, then develop and apply bespoke technologies developed by the Hamlyn Centre BSN engineering team supported by the EPSRC ESPRIT programme to deliver post-operative monitoring options for patients undergoing reconstructive surgery. A wireless optical sensor was developed to provide a continuous monitoring solution for free tissue transplants (free flaps). By recording backscattered light from 2 different source wavelengths, we were able to estimate the oxygenation of the superficial microvasculature. In a custom-made upper limb pressure cuff model, forearm deoxygenation measured by our sensor and gold standard equipment showed strong correlations, with incremental reductions in response to increased cuff inflation durations. Such a device might allow early detection of flap failure, optimising the likelihood of flap salvage. An ear-worn activity recognition sensor was utilised to provide a platform capable of facilitating objective assessment of functional mobility. This work evolved from an initial feasibility study in a knee replacement cohort, to a larger clinical trial designed to establish a novel mobility score in patients recovering from open tibial fractures (OTF). The Hamlyn Mobility Score (HMS) assesses mobility over 3 activities of daily living: walking, stair climbing, and standing from a chair. Sensor-derived parameters including variation in both temporal and force aspects of gait were validated to measure differences in performance in line with fracture severity, which also matched questionnaire-based assessments. Monitoring the OTF cohort over 12 months with the HMS allowed functional recovery to be profiled in great detail. Further, a novel finding of continued improvements in walking quality after a plateau in walking quantity was demonstrated objectively. The methods described in this thesis provide an opportunity to revamp the recovery paradigm through continuous, objective patient monitoring along with self-directed, personalised rehabilitation strategies, which has the potential to improve both the quality and cost-effectiveness of reconstructive surgery services.Open Acces

An Unusual Metastasis of a Transglottic Squamous Cell Carcinoma to the Forearm

Introduction. Each year around 2,200 people in the UK are diagnosed with laryngeal SCC (Office of National Statistics 2009). Compared to pharyngeal carcinoma, it is a highly curable disease with a survival rate of around 60% for all stages and all forms of treatment. Case Presentation. We present the case of a 60-year-old man with a previously treated T4 N2c transglottic squamous cell carcinoma (SCC), who developed an isolated swelling in the extensor compartment of his right forearm at 6 months after radical laryngectomy with bilateral neck dissection. Fine needle aspiration of the forearm lesion revealed SCC consistent with a metastasis from the laryngeal primary. MRI revealed that the lesion was confined to the muscle. Initial staging CT showed no distant metastases or signs of advanced disease, including no evidence of axillary nodal involvement. Conclusion. This case is therefore unusual, as one of only 2 cases reported in the scientific literature of isolated distant muscular metastasis from a laryngeal squamous cell carcinoma. We conclude that any muscular swelling, in the setting of previous head and neck malignancy, should be treated with a high degree of suspicion for metastasis and investigated promptly