Finger Sprain

• Finger sprains are injuries to ligaments in the digits of the hand.
• Splinting, buddy taping, and rest treats most finger sprains. Some injuries may require surgery.
• RICE (rest, ice, compression, and elevation) may be a useful home remedy for a finger sprain.

The finger has complicated anatomy because of the tendons that intertwine and cross the joints. In addition, there are arteries, veins, and nerves in each finger.

Each finger (index, middle, ring, and little or pinky) has three bones*:

• The proximal phalanx
• The middle phalanx
• The distal phalanx
• *The thumb has two bones: the proximal and distal phalanx.

Proximal and distal are locations in the body in relation to the core. Proximal is closest to the body core and distal is further away. The fingernail is located over the distal phalanx.

There are three joints in each finger*:

• The metacarpophalangeal (MCP) joint joins the proximal phalanx to the palm.
• The proximal interphalangeal joint (PIP) joins the proximal and middle phalanx.
• The distal interphalangeal joint (DIP) joins the middle and distal phalanx.
• *The thumb has two joints the MCP joint and the interphalangeal (IP) joint.

There are collateral ligaments on each side of the MCP, PIP, and DIP joints in the fingers. These ligaments are on the sides of the joints and stabilize the joints while maintaining proper alignment (they prevent side to side movement).

Sprains are injuries to ligaments or tendons.

• Grade 1 sprain: Fibers in the ligament are stretched but not torn.
• Grade 2 sprain: The ligament is partially torn.
• Grade 3 sprain: A ligament tears completely.

There are many common finger injuries that involve the tendons and joints of the finger that can cause deformity and disability, but do not affect the ligaments.

• Mallet finger
• Boutonniere deformity
• Jersey finger

Finger sprains are injury from trauma, usually because of a direct blow to the finger, which is forced into a forced side-to-side movement. Most often the collateral ligaments of the PIP joint of the finger are involved. The mechanism of injury is often a jammed finger.

Falling is the most common reason to damage and sprain the thumb. This injury is commonly called skier's thumb because the thumb is stretched away from the rest of the hand by the ski pole during a fall. The injury is also called a gamekeeper's thumb because of the ligament would become weak due to repeated stretching when gamekeepers would kill small animals by breaking their necks. Chronic thumb (UCL) sprains are also seen in volleyball players who set the ball with outstretched hands.

Acute finger sprains are caused by injuries, either due to a fall or a direct blow or twist to the finger or hand.

An acutely sprained finger causes localized pain and swelling. There may be finger deformity. There may be difficulty bending or straightening the finger and pain with range of motion. This is especially true if there are other associated injuries involving the joint or the finger, including fracture and dislocation.

Numbness and tingling may be present in the finger if the digital nerves are bruised or torn.

Medical professionals make a diagnosis of a finger sprain by getting the patient's history to understand how the injury occurred and performing a physical examination.

A physical exam of the affected finger may include the following:

• Observing whether there is any obvious deformity
• Taking the finger through a full range of motion of each joint (MCP, PIP, and IP of each finger; the MC and IP in the thumb). This may be done both actively, asking the patient to fully flex and extend each joint, and passively, when the provider performs the movement.
• The collateral ligaments are tested by trying to move or stress the joint side to side to assess the stability or laxity of the injured joint. Often the joint laxity is compared to the finger of the unaffected hand.
• With any injury, it is important to assess the blood supply and sensation to the finger.

Medical professionals may take X-rays to make certain there are not associated fractures, especially if a joint is markedly swollen.

Most finger sprains are relatively minor and heal on their own with symptomatic care, including RICE (rest, ice, compression, and elevation) buddy taping, splinting, and time.

More severe or unstable finger collateral ligament sprains or those associated with fractures may require surgery to stabilize the injury.

Rest, ice, compression, and elevation are helpful with any injury, including finger sprains. Children's finger injuries should often be seen by a care provider because of potential fractures.

Buddy taping an injured finger to one adjacent can help support the finger during healing, but it is important to be certain that the joints are not held immobile for too long, otherwise range of motion will be lost and it will take significant time and physical therapy to return the range of motion to normal.

The goal of treatment for a finger sprain is to return the finger and hand to the function it had before injury and this is usually the case. Mild finger sprains may take one to two weeks to heal. Grade 3 sprains and those associated with fractures and dislocation may take months

Most finger sprains are accidental and due to a fall or local injury. Preventing falls on an outstretched hand not only prevents finger sprains but a host of other hand and wrist injuries.

Finger sprains due to repetitive injuries (most often chronic thumb UCL sprains) may be preventable by improving technique or supportive taping of the thumb and hand.