A crutch is a specialized mobility aid designed to transfer a person’s body weight from the lower extremities to their upper body and torso. This device is typically necessary following a temporary injury, surgery recovery, or due to a long-term disability that affects the ability to walk or bear weight. The primary function of a crutch is to maintain balance and facilitate safe ambulation, allowing the user to move while protecting the injured limb.
Understanding the Main Types of Crutches
The most recognized style is the axillary or underarm crutch, generally recommended for short-term use following an acute injury or surgery. This type features an axillary pad that fits beneath the armpit, a handgrip, and a foot piece. Weight must be supported by the hands and arms, not the armpits, as misuse can lead to nerve damage. Axillary crutches are widely available and relatively easy for a new user to learn.
A different option is the forearm crutch, often called a Lofstrand or Canadian crutch, which is better suited for long-term mobility needs. This style has a handgrip and a cuff that secures the forearm just below the elbow. Forearm crutches require good upper body strength and coordination but offer more maneuverability and are often preferred by people with chronic conditions.
A third, less common variety is the platform or trough crutch, designed for individuals who cannot grip the hand bar due to weakness, arthritis, or a hand/wrist deformity. With this model, the forearm rests on a horizontal padded platform and is often secured with a strap. The weight is transferred through the forearm rather than the wrist and hand.
Ensuring Proper Fit and Sizing
Correctly sizing a crutch is essential for preventing secondary injuries and ensuring safe movement. The overall height of an axillary crutch must be adjusted so the axillary pad sits 1 to 2 inches below the armpit, roughly the width of two fingers. This gap prevents the pad from pressing into the axilla, where major nerves and blood vessels are located. Excessive pressure can cause crutch paralysis (radial nerve palsy), leading to weakness or numbness in the arm and hand.
The placement of the handgrip is equally important, as it bears the majority of the user’s weight. When standing upright, the handgrip should be adjusted so the elbow is flexed at approximately 20 to 30 degrees. This slight bend allows the arms to push down effectively, transferring the body’s weight through the hands. The handgrip height is typically aligned with the user’s wrist crease when their arm hangs naturally by their side.
The overall crutch height is generally set first, followed by the handgrip adjustment. The crutch tips should rest on the floor about 4 to 6 inches outside and in front of the feet to create a stable base, often referred to as the tripod stance.
Fundamentals of Walking with Crutches
Movement depends on the prescribed weight-bearing status of the injured leg. Non-weight bearing (NWB) means the injured leg cannot touch the floor, while partial weight bearing (PWB) allows a specified amount of the body’s load, such as 25% or 50%. The most common technique for NWB is the three-point gait, which uses the crutches and the uninjured leg for support.
To execute the three-point gait, the user first moves both crutches and the injured leg forward simultaneously, establishing a new base. The user then pushes down on the handgrips, transferring weight to their arms, and swings the uninjured leg through to land in line with or slightly ahead of the crutches. For PWB, the injured foot is permitted to touch the ground with the allowed weight as it moves forward with the crutches.
Navigating stairs requires a modified technique, easily remembered with the phrase “up with the good, down with the bad.” When ascending, the uninjured leg steps up first, followed by the crutches and the injured leg. When descending, the crutches and the injured leg lead the way down to the next step, while the uninjured leg follows.