What Is Metacarpal Fracture

Metacarpals are long, thin bones that make up the palm of the hand. They are located between the carpal bones in the wrist and the phalanges (fingers), each consisting of a base, the proximal part of the bone, a shaft, a neck, and a head (the most distal part of the bone). A metacarpal fracture is one of the most common types of hand fractures. 

Hand fractures are fairly common and tend to be seen in individuals who partake in contact sports such as boxing or rugby. Metacarpal fractures usually occur following a fall directly onto the hand or a direct hit.

The majority of metacarpal fractures are isolated injuries, which are simple (a result of excessive force), closed (broken bone with skin intact), and stable (a broken bone with minimal damage). Up to 40% of all hand fractures are metacarpal fractures; they also comprise roughly 20% of all fractures that occur below the elbow.¹

Overview

A metacarpal fracture is a type of bone fracture that affects the bones in hand. A range of factors can cause this type of fracture, including sports-related injuries, falls, or even car accidents.¹

Causes of metacarpal fracture

A metacarpal bone fracture can occur for various reasons. Metacarpal fractures normally appear in patients aged between 10 and 40 years old, with individuals assigned to the male gender at birth (PAMAB) (85%) more likely to be affected than those assigned to the female gender at birth (PAFAB). Some common causes include injuries sustained during sporting activities, falls, or accidents involving motor vehicles. Young PAMAB sustains metacarpal fractures from a punching motion or any type of direct blow to the hand, while elderly PAFAB over 65 years have an increased risk of metacarpal fractures due to falls.

Metacarpal fractures are differentiated by their pattern. The most common type seen in young PAMAB is a fracture to the pinky (boxer’s fracture). This results from a punch with a closed fist, and the metacarpal neck is the weakest point of the bone. The fracture can affect metacarpal bones in digits 2 through 5, excluding the thumb. The 5th metacarpal (the pinky) is the most commonly injured metacarpal. In general, metacarpal fractures account for 40% of all hand fractures, whilst 10% of hand fractures are 5th metacarpal fractures (pinky finger).²

Metacarpal shaft fractures are a result of a direct high-energy impact or fall and can be subdivided into the following:

1. Transverse fracture refers to a broken bone that involves a single fracture line. It typically affects long bones in the body and can also be referred to as a complete fracture, implying that the line of the breakage goes all the way through your bone.
2. Oblique fracture: oblique fractures break diagonally across the width of a bone and along the longitudinal axis of the bone. The edges of the bone are usually fairly sharp and can cause lacerations to the skin.
3. Comminuted fracture: this refers to when the bone breaks in several places. Metacarpal base fractures and head fractures are less common and often comminuted.

Signs and symptoms of a metacarpal fracture

In the event of a metacarpal fracture, some common indicators include:

• Immediate and intense pain
• Reduced range of movement
• Swelling
• Weakness in the hand/ tenderness
• Fingers crossing over 
• Bruising

On observation, the hand will typically appear very swollen, and in the area where the bone is broken, there may also be an obvious lump or deformity. This is a result of bone displacement or movement when the metacarpal breaks.

Management and treatment for a metacarpal fracture

The main aim of treatment for metacarpal fractures is restoration of hand function, and treatment can include surgical and non-surgical interventions. Treatment methods for metacarpal fractures vary depending on several factors, including whether the fracture is open (where the bone comes through the skin) or closed (where there is no break in the skin), the number of fingers/ metacarpals fractured, the number of breaks, and displacement.

General guidelines for non-operative management of metacarpal fractures are outlined below.¹

Non-operative management

1. Pain relief
2. Prophylactic antibiotics for reducing infection risk with open fractures
3. Guided physiotherapy exercises, with a goal to increase range of motion and strength
4. Use of a splint (rigid support protecting displaced bones during the healing process) can be worn for several weeks with the guidance of a healthcare professional.

Operative treatment

Surgery is typically required in cases where the fracture is accompanied by an open wound, involves an intraarticular fracture, exhibits segmental bone loss, or when multiple hand and wrist fractures are present.

1. Metacarpal neck fracture: Open reduction and internal fixation using K-wires, plating, intramedullary (IM) pins, or a more recent intraoperative kickstand technique are the procedures of choice.
2. Metacarpal head fracture: Often articular and comminuted requiring K-wire fixation, lag screw, Metacarpophalangeal joint arthroplasty (MCP arthroplasty) or MCP fusion.
3. Metacarpal shaft fracture: lag screw fixation or single screw with a neutralisation plate or K-wires, depending on the structure of the fracture line.³

Following surgery, intensive treatment by a Physiotherapist can minimise stiffness.

Diagnosis

A healthcare professional will use the following to assist in the diagnosis of a metacarpal fracture:

• Visual observation
• X-ray
• CT scan
• MRI

FAQs

How can I prevent a metacarpal fracture?

Some causes of metacarpal fractures are unavoidable, such as an accident; however, there are ways to reduce fall risks, such as avoiding wet floors and maintaining a healthy diet with enough calcium and vitamin D intake.

How common is a metacarpal fracture?

Metacarpal fractures account for 18–44 % of all hand fractures.¹

Who is at risk of a metacarpal fracture?

Metacarpal fractures can affect anyone at any stage of life. However, this type of fracture is usually witnessed in young PAMAB due to a direct impact on the elderly as a result of a fall.

What can I expect if I have a metacarpal fracture?

It is normal to still experience aches and pain after recovery, especially when returning to previous activities. However, if this persists, it is best to have a follow-up with a healthcare provider.

How long does a metacarpal fracture heal?

Metacarpal fractures typically take 6 - 8 weeks to heal; however, follow-ups with a healthcare professional will be required to confirm the healing process.

When should I see a doctor?

You should seek a doctor’s advice following a high-energy fall or any high-pressure direct impact to the hand with the following symptoms:

• Immediate and intense pain
• Reduced movement
• Swelling
• Weakness in the hand
• Digits crossing over/ dislodged 

Summary

A metacarpal fracture is a bone fracture that affects the bones in the palm of the hand, and can affect anyone at any age. This type of fracture can be a result of a sports-related injury, a fall, or even a car accident. Symptoms include intense pain, reduced movement, swelling, and weakness in the hand; medical assistance should be sought immediately. There are several different patterns of fractures, each with a different treatment requirement. However, regardless of whether treatment is surgical or non-surgical, the main aim of treatment is anatomical restoration and hand function.