Osteoarthritis (OA): Given the patient's age and the presentation of pain in multiple joints, OA is a common condition that affects joints due to wear and tear, leading to pain and stiffness, especially in weight-bearing joints and hands.

Rheumatoid Arthritis (RA): An autoimmune disorder that causes inflammation and pain in multiple joints, often symmetrically. It's a common cause of polyarthritis and should be considered, especially if there's morning stiffness lasting more than an hour.
Gout: A form of inflammatory arthritis characterized by sudden, severe attacks of pain, swelling, redness, and tenderness in one or more joints, most often in the big toe. It's more common in men and can affect multiple joints over time.
Psoriatic Arthritis (PsA): A condition that combines the swollen, scaly skin of psoriasis with joint pain and arthritis. Symptoms can range from mild to severe and may include joint pain, stiffness, and swelling, as well as skin and nail changes.

Lyme Arthritis: Given the patient's location in Massachusetts, which is an area endemic for Lyme disease, Lyme arthritis is a critical diagnosis not to miss. It can cause intermittent or persistent arthritis, typically in one joint (often the knee), but can occasionally affect multiple joints.
Septic Arthritis: Although less common, septic arthritis is a medical emergency that requires prompt diagnosis and treatment. It can present with acute onset of pain, swelling, and decreased range of motion in one or more joints, often accompanied by systemic symptoms like fever.
Crystal Arthropathies (e.g., Pseudogout): Conditions like calcium pyrophosphate deposition disease (CPPD) can cause acute or chronic arthritis in multiple joints and should be considered, especially if there's a history of similar episodes or if the patient has risk factors like hemochromatosis or hyperparathyroidism.

Sarcoid Arthritis: A condition where sarcoidosis, an inflammatory disease, affects the joints, causing pain, swelling, and stiffness. It's less common but should be considered in the differential diagnosis, especially if there are other systemic symptoms like lung involvement or skin lesions.
Hemochromatosis-related Arthritis: A condition where excessive iron storage leads to joint pain and arthritis, typically affecting the second and third metacarpophalangeal joints, among others. It's a rare cause of polyarthritis but important to diagnose due to its systemic implications.
Relapsing Polychondritis: A rare autoimmune disorder that can cause cartilage inflammation, leading to joint pain and arthritis, among other symptoms like ear and nose cartilage involvement. It's a diagnosis to consider in patients with a complex presentation of arthritis and other systemic symptoms.