Arthritis of the MCP joint
The metacarpophalangeal joint is colloquially known as knuckles. It is composed distally by the proximal phalange (the finger bones), and proximally by the metacarpal (the bones of the hand). This joint can become arthritic due to wear and tear, trauma, infection, autoimmune processes, and crystal depositions.
Knowing the causes of arthritis help explain wht the joints of the hands are so commonly affected. There is barely any activity that could be done without using the hands, which puts those joints at an increased risk for injury and causes them to wear with time.
The index finger and the thumb are more commonly affected than the other fingers. These two fingers are essential for fine motor activities like grasping, holding, pinching, writing and eating. When the metacarpophalangeal joint of these fingers becomes arthritic can cause patients to become incapacitated.
The patient usually presents with pain and stiffness of the base of the thumb and/or the knuckles. These can be accompanied by swelling, decreased range of motion, and difficulty performing tasks like turning a doorknob, grasping small objects, and opening bottles. These symptoms would gradually worsen from pain only with movement to pain at rest, loss of motion, and joint deformity.
Diagnosis is going to be made by your physician after an evaluation that includes history, physical examination, and imaging. Your physician will explore causes for arthritis that might consist of osteoarthritis, rheumatoid arthritis, and gout, among others, and assess the joint's range of motion and tenderness. A definitive diagnosis is made with an X-ray.
Conservative treatment is first-line and consists of activity modification, anti-inflammatory medications, topical analgesics, physical therapy, splinting, and cortisone injections. If non-surgical treatment fails, surgical treatment options can be considered.
A joint implant replacement is a surgical option in all fingers but the thumb. This procedure is called arthroplasty. Another surgical approach commonly done, especially on the thumb, is arthrodesis. The metacarpophalangeal joint is immobilized during this procedure by fusing the metacarpal bone and the phalangeal bone. A third option would be a synovectomy where the joint lining is removed and the tendons are realigned.