M18.10

Clinical Causes: Age-related cartilage wear and tear Repetitive hand movements and joint overuse Genetic predisposition to joint degeneration Previous thumb injuries or trauma Joint misalignment or abnormal biomechanics Hormonal factors, especially in postmenopausal women

Key Symptoms: Pain at the base of the thumb, particularly during activities that involve gripping or pinching Tenderness when touching the thumb joint Swelling or inflammation around the joint Stiffness, especially after periods of inactivity Reduced thumb range of motion A feeling of weakness or instability in the thumb Grating or a catching sensation during thumb movement

Diagnosis Path: Medical history review, focusing on symptom onset, duration, and activity-related aggravation Physical examination to evaluate tenderness, swelling, range of motion, and joint stability Specialized tests, such as the grind test, to reproduce symptoms Imaging studies, primarily X-rays, to visualize joint space narrowing, bone spurs, and joint destruction Exclusion of other conditions that could mimic osteoarthritis, such as rheumatoid arthritis or ligament injuries

Treatment Protocols: Conservative approaches: Thumb splints or braces to stabilize the joint and prevent pain during activities Non-steroidal anti-inflammatory drugs (NSAIDs) to alleviate pain and inflammation Activity modifications to avoid strenuous thumb movements Physical or occupational therapy to strengthen surrounding muscles and improve joint function Corticosteroid injections for short-term pain relief Use of assistive devices such as ergonomic tools to reduce joint stress Weight management if applicable, to lessen joint load Surgical options: Trapeziectomy: removal of the trapezium bone to reduce joint pain Ligament reconstruction and tendon interposition (LRTI) Joint fusion (arthrodesis) for severe cases Joint replacement (arthroplasty), although less common Post-treatment rehabilitation to restore mobility and strength