From the Guidelines
For an avulsion fracture in the foot, a posterior splint or a stirrup splint is typically used for initial immobilization. The choice of splint depends on the specific location of the avulsion fracture. According to the 2024 American Heart Association and American Red Cross guidelines for first aid 1, splinting of a fractured extremity can be useful to reduce pain, reduce risk for further injury, and facilitate transport to a medical facility.
- A posterior splint extends from below the knee to the toes, maintaining the foot at a 90-degree angle to prevent equinus deformity.
- A stirrup splint wraps around the foot and ankle in a U-shape for lateral stability. The splint should be applied with padding to prevent pressure sores and should remain in place for 1-2 weeks until swelling subsides, after which the patient may be transitioned to a walking boot or cast depending on fracture healing. During this time, the patient should follow RICE protocol (rest, ice, compression, elevation) and avoid weight-bearing on the affected foot until cleared by a healthcare provider. Immobilization is crucial as it prevents displacement of the bone fragment that has been pulled away by tendon or ligament forces during the injury, allowing proper healing to occur. It is also important to cover open wounds associated with a suspected fracture with a clean dressing to lower the risk for further contamination and infection, as recommended by the guidelines 1.
From the Research
Avulsion Fracture in Foot: Splint Usage
- An avulsion fracture in the foot, specifically at the base of the fifth metatarsal, can be treated with different types of splints or casts, depending on the severity and location of the fracture.
- According to 2, a fifth metatarsal tuberosity avulsion fracture can be treated acutely with a compressive dressing, followed by a transition to a short leg walking boot for two weeks, with progressive mobility as tolerated after initial immobilization.
- Another study 3 compared the use of an Aircast walking boot and a below-knee walking cast for avulsion fractures of the base of the fifth metatarsal, and found that patients treated with a walking boot reported less pain and had better functional outcomes than those treated with a short-leg cast.
- The study 3 also found that patients treated with a walking boot returned to their pre-injury level of function and pain approximately 3 weeks earlier than those treated with a short-leg cast.
Types of Splints Used
- Compressive dressing: used acutely for fifth metatarsal tuberosity avulsion fractures 2
- Short leg walking boot: used for fifth metatarsal tuberosity avulsion fractures 2 and avulsion fractures of the base of the fifth metatarsal 3
- Below-knee walking cast: used for avulsion fractures of the base of the fifth metatarsal 3
- Aircast walking boot: used for avulsion fractures of the base of the fifth metatarsal and found to be a better treatment option than a short-leg cast 3