Background: Musculoskeletal ultrasound (MSUS), which is also known as the rheumatologist's third eye, stethoscope, or extended finger, is now widely regarded by rheumatologists as an extension of their clinical examination and a crucial tool in their diagnostic collection. Objective: Assessment of ultrasonography in the early stage of rheumatoid arthritis and psoriatic arthritis. Methods: Ultrasonography, Early stage, Rheumatoid arthritis and Psoriatic arthritis were all looked for in PubMed, Google scholar, and Science direct. References from relevant literature were also evaluated by the authors, but only the most recent or complete study from November 2001 to November 2021 was included. Due to the lack of sources for translation, documents in languages other than English have been ruled out. Papers that did not fall under the purview of major scientific investigations, such as unpublished manuscripts, oral presentations, conference abstracts, and dissertations, were omitted. Conclusion: As there is no ionizing radiation or claustrophobia risk, US is a reasonably affordable and patient-friendly imaging technique. Due to MSUS's great sensitivity in identifying inflammatory and structural lesions, this imaging technique may definitively identify the pathology behind symptoms including pain, stiffness, and restricted range of motion.