# Hand Neuropathies and Musculoskeletal Disorders: Complementary Diagnosis Using IR Thermography
###### Abstract
On the other hand, when the ulnar nerve gets compressed while passing trough the cubital tunnel on the inner side of the elbow, the second most prevalent entrapment neuropathy arises, known as Cubital Tunnel Syndrome (CuTS) [16]. Although the cubital tunnel is the most common area of compression, ulnar nerve damage can also occur from C8-T1 nerve root fibers to the wrist [17]. In this condition, the compression of the ulnar nerve  
Figure 1: Distinct sensory areas supplied by the hand’s nerves. nerve, responsible for controlling muscle movements in the forearm and ring and little fingers, can be caused by prolonged or repetitive elbow flexion, extension, pronation, or supination, gripping, lifting, traumatic injuries, and specific diseases [17; 18]. While CuTS presents a risk four times greater for developing advanced disease compared to CTS [3], its symptoms are quite similar, encompassing numbness, paresthesia, hand atrophy, pain in the affected hand and forearm, and reduced grip strength due to weakness in the muscles of the flexor carpi ulnaris (FCU) and the flexor digitorum profundi (FDP) [1; 3; 17]. Nevertheless, CuTS mainly affects the medial hand and ring and pinky fingers. Patients with clinical conditions such as diabetes or advanced age complain of motor symptoms (loss of grip strength, weakness, difficulty with fine motor tasks) more often than sensory symptoms (numbness, tingling, paresthesia) usually reported by younger patients. Furthermore, Radial Tunnel Syndrome (RTS) is a relatively uncommon neuropathic condition that occurs due to the compression of the posterior interosseous nerve, the terminal motor branch of the radial nerve, as it traverses the radial tunnel, a region within the proximal forearm [3]. The prevalence of RTS is relatively low compared to Carpi Tunnel Syndrome or Cubital Tunnel Syndrome and it is estimated to impact a small percentage of the population, affecting 0.0035% of the population per year [19; 20]. This rarity can often lead to misdiagnosis or delayed recognition, making accurate diagnosis and appropriate management crucial. The underlying causes of Radial Tunnel Syndrome are multifactorial and can include a combination of anatomical factors, repetitive overuse, and most commonly trauma, such as humerus fractures [21]. The compression of the radial nerve can result from factors such as muscle hypertrophy or inflammation, as well as external pressure or repetitive motions that place stress on the nerve. Symptoms of RTS typically manifest as pain and discomfort in the forearm, particularly in the area around the radial tunnel [22]. Individuals with RTS may experience aching, burning, or sharp pain, often exacerbated by activities that involve gripping, twisting, or extending the wrist and hand. Weakness in the affected arm and wrist, namely in the extensor carpi radialis longus and extensor carpi brevis, and in the metacarpophalangeal joints of the thumb and fingers and the interphalangeal joint of the thumb, may result, respectively, in disrupted extension of the fingers and radial deviation of the wrist during extension, impacting a person's ability to perform everyday tasks and activities [19]. Orthopaedic conditions of the hand encompass a diverse range of musculoskeletal disorders that affect its anatomy and functionality. Among the multitude of hand-related pathologies, conditions such as rhizathrosis, tenosynovitis of Quervain, tendonitis of the flexors of the fingers, and osteoarthritis hold significant clinical relevance [2]. These conditions share a common characteristic of causing discomfort, pain, and functional impairment within the hand and wrist, often necessitating medical attention and intervention. Hand osteoarthritis is typically attributed to age-related joint wear and tear, although it can also be influenced by genetics. Joints in the hand, such as those in the fingers and the base of the thumb, are affected. Rhizathrosis is primarily caused by wear and tear on the carpometacarpal (CMC) joint at the base of the thumb.