Surgery for the CMC joint can be performed in various clinical settings and involves ligament reconstruction or tendon interposition. The post-surgical therapy program varies depending on the surgical technique and clinical location. Patients usually must wear a thumb spica cast for four weeks. Surgical procedures require the CMC joint to be immobilized with a thumb spica cast.
The CMC joint is an extremely complex M-shaped joint connected to the midcarpal joint and the joint space between the trapezium and the trapezoid bone. Its anatomy and common contours surround the quadrangular joint, making it highly constrained.
The CB may develop after a fracture to the trapezoid bone, a second MC fracture, or severe traumatic luxation of the CMC joint. Surgical studies often reveal the presence of CB. Identifying the cause of this condition is important, as early diagnosis is essential for successful treatment.
Many investigators have studied the anatomy of the CMC joint ligaments. However, a lack of agreement on terminology and definition has hindered the development of an accurate understanding of their function. The second metacarpal base generally fits into the trapezoid bone as an inverted V, while the third metacarpal base fits into the capital bone as an inverted C. A narrow region in the third metacarpal base contains the insertion of the ECRL tendon.
The trapezoid bone is one of the eight bones of the wrist. The trapezium sits on top of the scaphoid bone, forming the Scapho-Trapezio-trapezoid joint (STT). Arthritis of the trapezoid pooled results from an excessive range of motion.
The trabecular thickness of osteoarthritic and normal trapeziums was similar in both groups. However, the trabecular thickness was lower in the osteoarthritic trapeziums. However, the differences in the trabecular thickness were not statistically significant.
The CMC joint of the thumb is a saddle-shaped joint that allows for a wide range of motions in the thumb. These include extension and flexion, in/adduction, and opposition. In addition, the CMC joint is often referred to as the thumb’s basal joint.
The trapezoid bone is a small, oblong bone that contributes to the stability and mobility of the wrist and hand. It is connected to the first metacarpal using four joints. It also forms a saddle joint with the second metacarpal, enhancing the index finger’s mobility.
The base of the fifth metacarpal
The base of the fifth metacarpal in the CMC joint is often associated with the bottom of the fourth metacarpal. This fracture may involve disruption of the longitudinal axis and dorsal displacement. Other clues include a severely angulated metacarpal. This type of fracture is similar to a Bennett fracture of the first metacarpal. It may also have an ulnar offset of the fifth metacarpal.
Surgical procedures for fifth-CMC arthritis include 5th CMC arthroplasty, silicone elastomer interposition arthroplasty, and tendon interposition. In most cases, fifth-CMC arthroplasty is performed to remove the fifth metacarpal base and fuse the fifth metacarpal with the fourth. Most surgeons prefer autologous cancellous bone grafts.
This is a rare injury, but it cannot be easy to detect if the base of the fifth metacarpal is fractured. In most cases, the fracture will present with significant displacement, especially when the fracture occurs on the ulnar side. In some cases, the fracture may also be associated with swelling in the palm or hypothenar eminence. The goal of treatment is early reduction and fixation. The success of this surgery depends on early diagnosis.
In some cases, a CT scan may be required to interpret the injury pattern better. This imaging can help the physician identify associated fractures and treat the fracture more effectively. If the fracture is present in the early stages of the fracture, closed reduction is usually successful. However, if multiple joints are involved, the fast removal can be unstable and may need percutaneous Kirschner wire stabilization.
A closed reduction under local anesthesia was unsuccessful in this case. After the fracture was reduced, the surgeon proceeded to open the removal the fifth CMC joint. A long incision was made over the base of the small and ring metacarpal bones to gain exposure to the joint. Afterward, the avulsed rim of bone and associated capsular tissue were removed. The surgical reduction was achieved, and the fifth CMC joint was repositioned in a lateral position. The surgeon fixed the fracture with a Kirschner wire inserted into the hamate.
Although the fifth CMC joint is less mobile than the fourth, it retains most of the flexion-extension arc. This preservation of motion contributes to improved grip strength and decreased thumb subsidence.
Basal joint of the thumb
The CMC joint, also known as the thumb’s basal joint, is located deep within the palm at the junction of the thumb metacarpal and trapezium. It is common to experience arthritis in the CMC, and symptoms may first develop during early adulthood. The symptoms of this condition include pain, swelling, and crepitus.
This joint enables a variety of movements of the thumb, including up/extension, down/flexion, in/adduction, palmar abduction, and opposition. The joint allows the thumb to move across the palm during grasping and pinching movements. Its special shape allows it to perform many of these motions.
Although the CMC joint functions well throughout life, it becomes unstable when its force increases over time. Healthy ligaments and articular cartilage help to dissipate the muscles across the joint, but ligaments can weaken and lose their ability to stabilize the joint. This can cause arthritic changes in the joint, as well as compensatory deformities in other distal joints.
Another common problem with this joint is osteoarthritis. It may occur due to age or trauma. In such cases, open reduction and internal fixation are required to fix the common. In addition, isolated subluxation of the CMC joint of the thumb may occur as a result of ligament injury. This joint instability can cause pain, weakness, grinding, and deformity.
If conservative treatment is not sufficient, surgery may be necessary. However, surgery should only be used if traditional measures fail and the pain hinders normal activity. The procedure is often performed on an outpatient basis under general or regional anesthesia. This anesthetic numbs the arm so the patient does not experience significant pain and can return to normal life.
Conservative treatment for CMC joint instability includes braces on the base of the thumb and anti-inflammatory medications. These options improve symptoms but limit activity. In addition, these treatments do not cure the problem, and symptoms may progress. Steroid injections are another option. They provide relief for 3 to six months, but the symptoms will return after the effect wears off.
Treatment options for a CMC joint include surgery, injections, and stem cell therapy. This type of treatment uses stem cells from bone marrow, which can differentiate into cartilage tissue. This can help restore damaged cartilage and promote the joint’s original function. In a recent study of 15 individuals with CMC arthritis, stem cell treatment significantly reduced pain. Patients reported that their pain decreased by half during activities.
Pain is the most common symptom of a CMC joint and is often aggravated by pinching or gripping. In severe cases, the constant pain can make it difficult to turn a doorknob. Inflammation of the tendons can also cause pain. The thumb can become swollen and painful, and the ligaments and tendons in the joint may become lax.
A doctor may prescribe NSAIDs, heat, or bracing to reduce swelling and pain in the CMC joint. Other treatments include steroid injections or physical therapy. Depending on the severity of the pain, a doctor may also prescribe low-dose narcotics.
A CMC joint may also undergo surgery. In severe cases, a CMC joint may need a complete replacement. This surgery removes the arthritic joint and bone. The surgeon may also use a bone-grafting device to repair the joint. This joint replacement is a viable option for some cases but may result in more complications.
Degenerative arthritis of the thumb CMC joint may result in contracture of the first web space, making it difficult to pinch objects. The joint may also become hyperextended, impairing the user’s grip and resulting in a “swan neck” deformity. This surgery is usually performed on an outpatient basis. However, it is important to understand that CMC arthroplasty is a complex procedure and may result in complications.
A CMC joint arthritis nonsurgical treatment plan should include rehabilitation services. These services aim to improve the quality of life for patients suffering from CMC joint arthritis. The rehabilitation process includes teaching patients how to reduce pain and use adaptive devices to relieve symptoms.