Carpal coalition the fifth to eighth weeks. The lunate and triquetral bones are the most common carpal bones to fuse together, resulting in a lunotriquetral coalition in 1% of people. 60% of patients with a lunotriquetral coalition will have it bilaterally. Among isolated incidents the capitate and hamate bones are the next most common to fuse followed by the pisiform-triquetrum, trapezium-trapezoid, scaphoid-capitate, and triquetrum-hamate. Carpal coalitions may further be divided into four subtypes: Generally since carpal-carpal fusions do not cause unease or discomfort for the patient, and do not impair wrist function, treatment is not needed. However, in the minority of cases
Limbs of the horse the pisiform is the back of the knee. Below the knee is the cannon bone which is also known as the 3rd metacarpal. 55 million years ago when the Eohippus existed, the cannon bone used to be the 3rd toe of the foot. Its fusion took place in order to increase height and power of the limb. Behind the cannon bone are the splint bones. The splint bones are also known as the 2nd and 4th metacarpal and fused 25 - 35 million years ago during the time of the Miohippus. They provide extra strength and support of the cannon