Bilateral knee and elbows weird sensatio

Based on the history and the investigations you have mentioned, inflammatory arthritis appears unlikely at present. You do not describe the typical features such as persistent joint swelling, significant pain, prolonged morning stiffness or progressive limitation of movement. Your current CRP is normal and ANA, RF, anti-CCP and HLA-B27 are negative, which is reassuring. The ANA 1:100 positive result from 2023 by itself does not diagnose an autoimmune disease. Low-titre ANA positivity can occur even in otherwise healthy individuals, and the fact that your current ANA is negative and you have no typical inflammatory symptoms makes it less concerning. The intermittent warm/burning or unusual sensation may therefore be mechanical, muscular or occasionally nerve-related, rather than arthritis. However, this cannot be confirmed from blood tests alone; examination of the knees, elbows and neurological system would help distinguish the cause.

At present, I would not recommend repeating multiple rheumatological tests solely because of these symptoms. Have an orthopaedic examination to assess joint movement, patellofemoral mechanics, muscle strength and neurological findings. Regular strengthening of the quadriceps, hamstrings and hip muscles, appropriate stretching and avoiding prolonged positions that reproduce the symptoms may help. If the burning sensation becomes persistent or is associated with tingling/numbness, a neurological evaluation and further tests can be considered based on examination.

Seek reassessment if you develop visible joint swelling, redness, persistent morning stiffness lasting >30–60 minutes, progressive joint pain, weakness or numbness. You can also consult me online with any previous reports or imaging so that the findings can be correlated with your symptoms before deciding whether further investigations are actually necessary.

Clinical Impression Yes, a nerve-, muscle-, or biomechanical-related origin is plausible. Low Likelihood of Inflammatory Autoimmune Arthritis: The absence of key inflammatory signs—such as visible joint swelling, localized redness, heat to touch, or prolonged morning stiffness (>30–60 minutes)—combined with normal CRP and negative specific markers (RF, Anti-CCP, HLA-B27) makes an active autoimmune inflammatory arthritis unlikely. Prior ANA Result: A low-titer positive ANA (1:100 in 2023) is seen in up to 15–20% of healthy individuals and frequently fluctuates or normalizes over time (as reflected by your negative 2026 test). In the absence of clinical autoimmune symptoms, an isolated low-titer ANA is generally considered non-specific. Neuropathic or Biomechanical Considerations: "Warm," "burning," or unusual internal sensations without joint inflammation are more characteristically associated with nerve involvement (such as localized nerve irritation, entrapment, or small-fiber neuropathy) or myofascial/tendon strain. Stiffness occurring specifically after activities like cycling often points to biomechanical pressure, posture, or repetitive stress on the joints and surrounding tendons.

Neurology or Physical Medicine Consultation: Consider an evaluation by a neurologist to assess for nerve-related origins, or a sports medicine/orthopedic physician to evaluate joint mechanics and tendon health. Nerve Diagnostic Testing: If burning sensations persist or spread, a specialist may recommend a Electromyography (EMG) / Nerve Conduction Study (NCS) or small-fiber evaluation. Ergonomic Assessment: Adjust your cycling setup (handlebar position, wrist alignment, saddle height) to ensure proper ergonomics and minimize mechanical strain on your elbows, hands, and knees.

Avoid Over-Interpreting Isolated ANA Titers: Low-titer ANA tests can be triggered transiently by stress, past viral infections, or normal biological variation. Red Flag Symptoms: Seek prompt medical evaluation if you develop visible joint swelling, significant localized redness, progressive muscle weakness, numbness/loss of sensation, or systemic symptoms like persistent unexplained fevers