Rheumatoid Arthritis (RA): Given the patient's family history of RA (mother with rheumatoid arthritis) and the presentation of frequent hand pains, especially if symmetric and involving the metacarpophalangeal and proximal interphalangeal joints, RA is a strong consideration. The absence of reported injuries reduces the likelihood of traumatic causes.

Osteoarthritis (OA): Although OA can cause hand pain, it typically affects the distal interphalangeal joints and is less likely to be symmetric or have a strong familial component like RA. However, it's common and should be considered, especially if the pain is localized to specific joints.
Tendinitis or Tenosynovitis: Inflammation of the tendons or their surrounding sheaths can cause hand pain, especially with activities. This could be related to overuse or repetitive strain injuries, even if the patient doesn't recall a specific incident.
Carpal Tunnel Syndrome: This condition, caused by compression of the median nerve, can lead to pain, numbness, and tingling in the hand, particularly at night. It's more common in women and could be a consideration, especially if the pain is accompanied by sensory symptoms.

Giant Cell Arteritis: Although less common, giant cell arteritis can cause hand pain and is a medical emergency due to the risk of vision loss if not promptly treated. It typically presents in older adults with symptoms like headache, jaw claudication, and visual disturbances, but hand pain can be a feature.
Infection (e.g., Septic Arthritis): An infectious cause could lead to severe consequences if not promptly diagnosed and treated. While less likely without a history of trauma or fever, it's crucial to consider, especially if the pain is severe, acute, and accompanied by systemic symptoms.
Neoplastic Processes: Tumors, either benign or malignant, can cause hand pain. Although rare, missing a diagnosis like a soft tissue sarcoma could have significant implications.

Scleroderma: A chronic autoimmune disease that can cause hand pain, swelling, and skin thickening. It's less common but should be considered if there are other systemic symptoms or skin changes.
Psoriatic Arthritis: Another autoimmune condition that can cause hand pain, typically in patients with psoriasis. The presence of skin lesions and specific patterns of joint involvement would suggest this diagnosis.
Reflex Sympathetic Dystrophy (Complex Regional Pain Syndrome): A condition characterized by chronic pain, inflammation, and hypersensitivity following an injury (which might be minor or even absent in the patient's recall). It's rare and would be considered if the pain is disproportionate to any apparent injury and accompanied by significant sensory and autonomic disturbances.