# Hand Neuropathies and Musculoskeletal Disorders: Complementary Diagnosis Using IR Thermography
###### Abstract  
Hand neuropathies and musculoskeletal disorders represent significant health concerns, often requiring accurate and non-invasive diagnostic methods. Current diagnostic approaches may have limitations in terms of accuracy and patient comfort. This study addresses the need for an improved complementary diagnostic tool for these conditions by investigating the potential of infrared thermography for identifying thermal patterns associated with these pathologies. Thermal images were acquired from both control participants with healthy hands and patients with hand neuropathies and/or musculoskeletal disorders. The mean temperatures of various regions of interest (ROIs) were analysed, and statistical tests were conducted to determine if there were significant temperature differences between the control and injury groups. The analysis consistently revealed higher mean temperatures in the injury group across multiple ROIs on both the dorsal and palmar aspects of the hand. [PERSON]'s test confirmed the equality of variances between the groups, supporting the validity of the statistical comparisons. The observed thermal differences between the control and injury groups underscore the potential of IR thermography for enhancing diagnostic precision of hand pathologies. Its integration into clinical practice could lead to early detection, personalised treatment, and improved patient care in the future. complementary diagnosis; infrared thermography; musculoskeletal disorders; neuropathies; upper extremity 20  
the overall quality of life. In recent years, infrared thermography (IRT) has emerged as a promising technology that has enormous potential to support the diagnosis and management of these conditions. Hand neuropathies and musculoskeletal disorders are debilitating conditions that can manifest in various forms, causing pain, discomfort, and loss of function in the hands [1,2]. Upper extremity neuropathies refer to conditions where there is impairment or malfunction of the nerves in the upper limbs, often resulting from factors such as compression, inflammation, and trauma [3]. The distinct sensory regions innervated by the hand's nerves, namely the median, ulnar, and radial nerves, are displayed in Figure 1.  
Prolonged compression of the median nerve within the wrist leads to the development of Carpal Tunnel Syndrome (CTS), the most prevalent entrapment neuropathy [4] affecting 7% to 19% of the population [5]. CTS is more common in women than in men and its incidence tends to increase with age [6]. In addition, conditions involving mechanical, traumatic, inflammatory, or hormonal factors, such as rheumatoid arthritis, diabetes mellitus, hypothyroidism, pregnancy, and morbid obesity, may contribute to heightened pressure within the carpal tunnel (higher than the normal pressure of 10 mmHg), thereby increasing the risk of CTS [7, 8, 9, 10, 11, 12, 13]. Activities and progressions characterised by repetitive hand and wrist movements of flexion and extension under significant force, such as forceful gripping, have also been linked to CTS [14]. In the earliest stage of the disease, the typical symptoms reported by patients with CTS include sleep disturbances due to hand numbness and a sensation similar to swelling and nocturnal brachialgia paraesthetica, which is described by pain extending from the wrist to the shoulder and tingling in the hand and fingers, and can be relieved by repeatedly shaking the wrists [5,13,15]. As the condition progresses, these symptoms also tend to occur during the day, and become more frequent when performing repetitive movements demanding prolonged wrist flexion, such as holding an object with the hands. In an advanced stage, weakness and potential hypotrophy or atrophy of the thenar muscles can be reported along with sensory loss in the first three fingers (thumb, index, and middle) and the radial side of the ring finger [4].