Differential Diagnosis for Joint Pain

The patient presents with joint pain in hands and knees, worsened by movement, and a recent episode of hands locking, without swelling, redness, or tenderness. Considering the patient's occupation as a carer and the onset of symptoms with colder temperatures, the following differential diagnoses are proposed:

• Single Most Likely Diagnosis
  • Osteoarthritis (OA): Given the patient's age and occupation, which may involve repetitive strain or heavy lifting, OA is a plausible diagnosis. The worsening of pain with movement and the locking of hands (possibly due to loose bodies or meniscal issues in the context of OA) support this diagnosis. The absence of swelling or redness also aligns with OA, as it is not typically characterized by significant inflammation.
• Other Likely Diagnoses
  • Rheumatoid Arthritis (RA): Although the patient does not exhibit swelling or redness, early or mild cases of RA could present with joint pain worsened by movement. The involvement of hands and knees is consistent with RA, but the lack of morning stiffness and systemic symptoms makes it less likely.
  • Psoriatic Arthritis (PsA): This condition could be considered if the patient has psoriasis or a family history of it. However, the absence of skin symptoms and the specific pattern of joint involvement make it less likely without further evidence.
  • Reactive Arthritis: Typically follows a gastrointestinal or urinary tract infection, which is not mentioned in the scenario. The patient's symptoms do not strongly suggest this diagnosis without a clear precipitating infection.
• Do Not Miss Diagnoses
  • Septic Arthritis: Although the patient does not have swelling, redness, or tenderness, septic arthritis is a medical emergency that must be considered, especially if the patient has a fever or recent history of infection. The absence of these signs does not rule out septic arthritis, particularly in immunocompromised patients.
  • Lyme Arthritis: If the patient has been exposed to ticks, Lyme disease could be a consideration, especially if the joint pain is intermittent and migratory. However, the locking of hands is not typical for Lyme arthritis.
• Rare Diagnoses
  • Hemochromatosis: A genetic disorder leading to iron overload, which can cause arthralgias and arthritis, particularly in the second and third metacarpophalangeal joints. It's less likely without other systemic symptoms or a family history.
  • Wilson's Disease: A rare genetic disorder causing copper accumulation, which can lead to arthritis among other symptoms. The diagnosis would be considered in the context of additional neurological or hepatic symptoms.

Each diagnosis is considered based on the patient's symptoms, occupation, and the potential for serious underlying conditions that require prompt identification and treatment. Further evaluation, including laboratory tests and potentially imaging studies, would be necessary to confirm the diagnosis.