Trigger finger (stenosing tenosynovitis) and Dupuytren’s contracture are common hand conditions that cause stiffness and difficulty with finger movement. Although both compromise hand function and can result in a bent appearance of the fingers, they are distinctly different disorders affecting separate anatomical structures. Understanding the differences in their pathology, symptoms, and progression is necessary for correct diagnosis and treatment.
Understanding Trigger Finger
Trigger finger involves the flexor tendons, which are cord-like structures that connect forearm muscles to the finger bones. These tendons slide through a protective tunnel called a tendon sheath, which is held close to the bone by pulleys. The disorder occurs when the tendon or its surrounding sheath becomes inflamed and thickened, restricting the tendon’s smooth gliding motion. Impingement most often occurs at the A1 pulley, located at the base of the finger near the palm.
The primary symptom is a characteristic catching, popping, or locking sensation when bending or straightening the affected digit. This restriction is caused by a small nodule or swelling on the tendon that catches against the narrowed A1 pulley opening. The finger may become stuck in a bent position, sometimes requiring the person to use their other hand to passively straighten it. Symptoms are often worse in the morning or after a period of inactivity; the ring finger and thumb are the most frequently affected digits.
Understanding Dupuytren’s Contracture
Dupuytren’s contracture is a progressive disorder involving the palmar fascia, a layer of connective tissue located just beneath the skin of the palm. The condition causes the fascia to thicken and shorten due to the abnormal proliferation of cells and the deposition of excess collagen. This thickening initially presents as small, firm, painless nodules under the skin of the palm.
Over time, these nodules mature into fibrous cords that extend into the fingers, pulling them into a fixed, bent position toward the palm (the contracture). The ring and little fingers are most commonly involved. The inability to straighten the finger is the defining functional limitation, and progression is typically slow, developing over months or years.
Distinguishing the Conditions
The fundamental distinction lies in the tissue affected: trigger finger is a tendon and pulley problem, while Dupuytren’s contracture is a fascia problem. Trigger finger involves the flexor tendon system, restricting the tendon’s ability to glide smoothly through its sheath. The lump associated with trigger finger is a nodule on the tendon that moves when the finger is flexed or extended.
The primary functional difference is how the finger is restricted. Trigger finger causes locking or catching upon active movement, but the finger can often be manually straightened. Dupuytren’s contracture involves a fixed flexion deformity, meaning the finger cannot be straightened at all due to the shortened cord, even with assistance. Trigger finger is often linked to repetitive hand use or conditions like diabetes, whereas Dupuytren’s contracture is primarily a genetic and fibrotic disorder associated with Northern European ancestry.
How Treatment Varies
Because the underlying pathology is different, medical interventions for these conditions vary significantly. Trigger finger treatment focuses on reducing inflammation and restoring smooth tendon gliding. Initial management often involves corticosteroid injections into the tendon sheath, which aims to decrease swelling and inflammation. If conservative options fail, a minor surgical procedure called an A1 pulley release can be performed to cut the constricted pulley and allow the tendon to glide freely.
Treatment for Dupuytren’s contracture focuses on releasing or removing the pathological fibrous cords causing the contracture. Non-surgical approaches include needle aponeurotomy, a minimally invasive technique where a needle divides the cord, or injections of an enzyme called collagenase, which chemically breaks down the cord tissue. For more advanced contractures, a surgical procedure known as a fasciectomy may be necessary to remove the thickened palmar fascia and cords to restore the finger’s range of motion.