Definition : A Fracture

A fracture is a break in the bone that can result from sudden force or repeated stress. It is manifested by symptoms such as pain, swelling and difficulty moving the affected area. Fractures can be classified into different types, such as open, closed, displaced and non-displaced, and their treatment varies according to their severity.

A fracture is a break in a bone. Most fractures result from a single, large force applied to normal bone.

In addition to fractures, musculoskeletal injuries include:

• Joint dislocations and subluxations (partial joint dislocations)
• Ligament sprains, muscle strains and tendon injuries.

Musculoskeletal injuries are common and vary considerably in mechanism, severity and treatment. The extremities, spine and pelvis can all be affected.

Musculoskeletal injuries can be isolated or part of a multisystem trauma. Most musculoskeletal injuries result from blunt trauma, but penetrating trauma can also damage musculoskeletal structures.

Fractures can be

• Open: The overlying skin is broken and the broken bone is in communication with the environment via a skin wound.
• Closed: The overlying skin is intact.

Pathologic fractures occur when a small or minor force fractures an area of bone weakened by a disorder (e.g., osteoporosis, cancer, infection, bone cyst). When the disorder is osteoporosis, these fractures are often called insufficiency or fragility fractures.

Stress fractures result from the repetitive application of moderate force, as may occur in long-distance runners or soldiers who walk while carrying a heavy load. Normally, bone damaged by moderate force microtrauma repairs itself during periods of rest, but repeated application of force to the same site predisposes to further damage and causes the microtrauma to spread.

A fracture is a break in the continuity of the bone. The first elements that can make us think of a fracture are

• the mechanism (impact, fall, etc.);
• pain (sudden and localized)
• functional incapacity (it is painful or impossible to perform certain movements)
• deformation (formation of an edema (swelling), angulation of the limb (fracture with displacement), sinking, etc.); possible presence of a hematoma.

These signs are not specific and may also indicate a joint problem (sprain, dislocation). Some fractures present reduced symptoms, such as the child's fracture known as "green wood", or a crack.

X-rays are the diagnostic test to demonstrate the presence of a fracture. X-rays can miss some fractures, mainly recent fractures without displacement. There are other ways to look for a fracture such as scintigraphy or CT scan.

he mechanisms of fracture can be :

• direct shock (part of the body receives a shock and breaks, the skin tissue is frequently affected);
• indirect shock (a part of the body receives a shock, the shock wave propagates in the bones and another distant but more fragile part breaks. For example: a person falls and lands on his hand, but breaks his elbow);
• bending (the bone is solicited in flexion);
• torsion (the bone is stressed in torsion).

The fracture of a bone is often not dangerous in itself, except near a vital organ or in the case of an open fracture.

When a fracture occurs, a local hematoma is produced. Inflammation allows the contribution of macrophages which will initiate the repair. Stem cells are recruited, transforming into chondroblasts or osteoblasts allowing bone regeneration. Several growth factors are involved.

A vascular and neurological assessment distal to the wound.

Inspection of open wounds, deformities, swelling, bruising.

Light palpation looking for tenderness, crepitus, and gross defects in bones or tendons.

Some findings may indicate a fracture or other musculoskeletal injury.

Deformity may indicate a fracture, but also dislocation or subluxation (partial separation of the bones of a joint).

Swelling is often a sign of a fracture or other significant musculoskeletal injury, but it may take several hours to develop. If there is no swelling within that time, the fracture is unlikely. For some fractures (e.g., loop fractures, small non-displaced fractures), swelling may be subtle, but it is rarely absent.

Tenderness accompanies almost all musculoskeletal injuries, and for many patients, palpation of any area around the injured area causes discomfort. However, a noticeable increase in tenderness in a localized area (point tenderness) suggests a fracture.

In some fractures, a defect may be palpable in the affected bone.

Crepitus (a characteristic palpable and/or audible grinding sound produced when the joint is moved) may be a sign of fracture.

Common types of fracture lines:

• Open fractures
  • These are considered contaminated because of the communication between the fracture site and the environment outside the body.
• Commutative fractures
  • They present > 2 bone fragments. Comminuted fractures include segmental fractures (2 separate fractures in one bone).
• Transverse fractures
  • These are perpendicular to the long axis of the bone.
• Spiral fractures
  • Result from a rotational mechanism; on radiographs, they can be distinguished from oblique fractures by a component parallel to the long axis of the bone on at least one view.
• Crush fractures:
  • These are caused when the bone is compressed or crushed. They are caused by accidents with high inertia.
• Green wood fractures
  • They are often associated with children. The term "greenstick fracture" is used because it refers to a young green branch that bends or splits, but does not break completely. As such, it is classified as an incomplete fracture, since only one side of the bone is broken while the other side is simply bent.
• Oblique fractures
  • These occur at an angle.

In impact fractures, the bone fragments push into each other, shortening the bone; these fractures may be visible as focal abnormal density in the trabeculae or irregularities in the bone cortex.

Torus fractures (deformation of the bone cortex) and greenstick fractures (cracks on only one side of the cortex) are infantile fractures.

The idea of a splint is to minimize the movement of damaged bones or joints. When a bone is completely broken, the pressure exerted on the broken pieces can cause the shredded pieces of bone to move and damage the softer tissues around it. For bones that are cracked, but not completely separated, external pressures on the bone can lead to increased damage and even potentially cause a broken bone to disintegrate completely.

The injury does not have to be a fracture. External pressures can make already damaged joints even more unstable. Whether the damage is to hard tissues such as bone or to complex soft tissues such as those in a joint, the treatment is based on immobilization.

To prevent external pressure from aggravating the damage to a broken bone, it is necessary to immobilize the affected area, i.e. splint it. Most fractures occur in the extremities (arms and legs), but there are bones throughout the body (about 206 in total). Even when the fractured bone is not in an extremity, such as the ribs or pelvis, it is vital to immobilize it as much as possible to reduce the risk of further injury. Most of the examples used here involve extremity fractures.

A limb splint will not work if you do not completely encapsulate the injury in the splint. This means that you must immobilize the joints above and below the fracture. If, for example, an arm is broken in the middle of the forearm, you will need to splint more than the forearm. Because a moving wrist or elbow puts pressure on the bones of the forearm, a fracture in this area also requires immobilization of the wrist and elbow. If they can't move, they won't be able to twist and bend the radius and ulna (forearm bones).

The reason for splinting an injury, especially a limb, is not to heal it. In many cases, severe fractures require extensive treatment, even surgery, to repair the damage.

A first aid splint is used to get the victim to the hospital or doctor. Sometimes a splint can make it easier to move the injured victim, either by allowing the victim to be moved without aggravating the injury, or by allowing the victim to move on his or her own.

While helping the victim get to the doctor, it is important not to make the situation worse. Above all, splints should not aggravate the injury to the extremity. Proper immobilization usually prevents worsening of the injury, which can be measured by assessing the function of the extremity. Circulation, sensation, and movement are characteristics of the function of all extremities.

Serious associated problems, if any, are treated first. Hemorrhagic shock is treated immediately. 

Blood flow to the injured area (circulation) can be disrupted if the surrounding tissue is damaged, including blood vessels. Anything strong enough to break a bone is strong enough to disrupt arteries, veins and capillaries.

To assess circulation, palpate the limb and its twin (if the right arm is broken, compare the right arm to the left arm) to check for heat. The injured end should be as warm as the opposite end. If it is cooler, it is a sign that blood flow to the area is compromised.

Compare the color. Purple, blue, mottled or pale are all signs of decreased blood flow to the extremity.

If you know how to take a pulse, compare the pulses in the extremities of the limbs. If the pulse in the injured extremity is absent or very weak, it is an indicator of circulatory problems.

The gold standard has always been to use capillary refill (apply gentle pressure to the fingernails or toenails to "bleach" or extract color, then release the pressure; the color is supposed to return in less than two seconds), but there is very little evidence that capillary refill is a reliable measure.

Presumed open fractures require sterile dressings

Sensation is the second measure of function. In this case, the test is simple: "Can you feel this?"

Without letting the victim see which toe or finger you are touching, ask him or her to tell you which one it is (keep it simple and use the pinkie or big toe, as middle toes and fingers are not always easy for patients to describe). If the victim does not feel you touching an extremity (or does not know what you are touching), it is a sign that the extremity is not getting enough blood flow, resulting in nerve dysfunction, or that there is actual nerve damage.

The final measure of function is movement. Can the victim move the extremity?

A loss of motion is an indicator of loss of circulation, motor nerve damage, or structural failure. Bones and muscles are just levers and pulleys designed to make things move in a certain way. If you break the support structure, sometimes the machine doesn't move the way it's supposed to.

Most moderate and severe fractures, especially those that are obviously unstable, are immediately immobilized with a splint (immobilization with a non-rigid or non-circumferential device) to decrease pain and prevent further soft tissue damage from unstable fractures. 

Immobilization decreases pain and facilitates healing by preventing further injury and maintaining alignment of the fracture ends.

Be sure to assess limb function at least twice. Check once before any treatment is applied and then again after splinting. If any of the functions (circulation, sensation and movement) have disappeared or worsened, try adjusting or even removing the brace. Loss of function is a significant problem that can lead to permanent damage if not managed.

Fractures in different areas of the body require different techniques to immobilize them. Starting at the top, let's look at the different types of splints and where they can be used most effectively.

Injuries to the shoulder girdle (clavicle and scapula) or upper arm (humerus) can only be treated properly with a sling and tape. Forearm injuries must be splinted with one of the techniques below, but can still be placed in a sling to help manage the injury. It is also easier for the patient to move if the splint is placed in a sling.

A sling is basically a hammock for your arm. It helps support the weight of the arm rather than letting it hang and pull on injured bones and tissues. A sling is used to attach the arm, still in the sling, to the patient's body.

Slings can be commercially made (typically after surgery) or they can be made from a triangular bandage or even a long shirt tail.

The most economical of all commercial splints is the cardboard splint. A cardboard splint is exactly as the name suggests, a cardboard splint designed for first aid. Cardboard splints can also be made from any type of thick-walled box. With a piece of cardboard, a roll of tape, a towel and a pair of scissors, almost any extremity fracture can be splinted.

Cardboard splints can be cumbersome and difficult to apply, and they don't work if they get wet. In addition, a cardboard splint can make it difficult to visualize an injured limb in order to reassess its function or to treat open wounds and control bleeding.

Malleable aluminum splints usually come in the form of a roll, but they can also come in a flat, padded version. Aluminum splints can be shaped very easily to fit an injured limb and they hold their shape in the rain. They are more expensive than cardboard, but take up much less space and can be applied more easily and with much less bulk once they are attached.

With practice, aluminum splints can be applied quickly, without hiding the end as much as a cardboard splint. Aluminum splints are also commonly used for finger splints and are sold in small, ready-to-use packages.

Ankle injuries can be properly repaired with a simple pillow and a roll of tape. A suitable pillow (down is not really suitable for this) can be wrapped around the foot of the injured ankle and taped around the leg. This effectively creates a soft "boot" to hold the injured ankle.

A pillow large enough can also be used to splint an arm or leg, although this is not ideal.

Danielle Campagne , MD: December 2022 "Overview of Fractures" https://www.merckmanuals.com/en-ca/professional/injuries-poisoning/fractures/overview-of-fractures?query=fractures [Last accessed January 20, 2023]

Rod Brouhard, EMT-P: October 7, 2021 "How to Splint a Broken Arm With Cardboard" https://www.verywellhealth.com/splinting-a-broken-arm-4020293 [Last accessed January 20, 2023]