Trigger finger is a painful condition in which a digit becomes bent in place because the underlying flexor tendon that regulates movement cannot readily migrate through its sheath to elevate or lower the finger.

Amniotic band syndrome (ABS) develops when the lining of the amniotic sac becomes injured during pregnancy. This produces string-like strands of tissue in which the fetus becomes bent. These strands (called amniotic bands) can wrap around various areas of the growing body. This stops (constricts) blood flow and prevents the fetus from growing normally. Constricted blood flow causes a variety of birth abnormalities. They can range from minor to severe deformities, limb loss, or life-threatening complications.

Ankle tendonitis, also known as Achilles tendonitis, is a disorder that causes inflammation and discomfort in the Achilles tendon, which connects the calf muscles to the heel bone. It is generally caused by overuse or repetitive tension on the tendon, resulting in small tears and inflammation.

A-2 pulley rupture, also known as flexor tendon sheath rupture, is a specific injury that affects the fingers, particularly in the context of climbing or other activities that place significant stress on the hands. The flexor tendons in the hand are crucial for bending the fingers, and they run through a series of pulleys to maintain their position close to the bones during movement. Among these pulleys, the A-2 pulley, situated in the middle phalanx of the finger, plays a critical role in stabilizing the tendon and preventing bowstringing during finger flexion.

Apert syndrome, also known as acrocephalosyndactyly type I, is a rare genetic disorder characterized by abnormalities affecting the skull, face, hands, and feet. This condition is classified as a type of craniosynostosis syndrome, where one or more of the fibrous joints (sutures) between the bones of the skull close prematurely, leading to abnormal skull shape and facial features.

A blue nevus, when it appears on the fingernail, is a benign skin lesion characterized by a blue or blue-black discoloration beneath the nail plate. These nevi typically arise from pigment-producing cells (melanocytes) in the nail matrix, which is the tissue at the base of the nail where new nail cells are formed.

Cellulitis is a common bacterial skin infection that affects the deeper layers of the skin and the underlying tissues. It can occur anywhere on the body but most commonly affects the legs. Cellulitis is typically caused by bacteria, most often Streptococcus or Staphylococcus species, entering the skin through a break or crack in the skin barrier.

Felon finger, also known as a felon or fingertip abscess, is a painful condition that involves an infection of the fingertip. It typically occurs when bacteria enter the finger through a break in the skin, such as a cut, puncture wound, or hangnail, leading to the formation of an abscess, or collection of pus, beneath the skin.