A broken bone (fracture) is a common injury causing pain and localized swelling. While these symptoms are expected, a fracture itself typically does not cause a fever. If a fever is present after a broken bone, it usually signals an underlying medical issue requiring prompt attention.
Understanding the Body’s Reaction to Injury
When a bone breaks, the body initiates an inflammatory response at the injury site. This localized inflammation causes common symptoms like pain, swelling, tenderness, and warmth around the affected area. Immune cells and inflammatory mediators rush to the site to clear damaged tissue and begin bone repair.
A fever, in contrast, is an elevated core body temperature, a systemic response often indicating infection or widespread inflammation. While localized warmth at a fracture site is due to increased blood flow, it does not raise overall body temperature to fever levels. Therefore, a simple, uncomplicated fracture is not expected to induce a fever.
Medical Causes of Fever Following a Fracture
A fever with a broken bone can indicate several medical complications. Infections are a primary concern, especially with open fractures where bone breaks through the skin, creating a direct pathway for bacteria. This can lead to wound infections or osteomyelitis, a serious bone infection causing fever, chills, sweating, and increased pain, redness, and swelling around the injury. Bacteria can also travel to a bone through the bloodstream from other infections, or after surgery to fix a fracture. Pneumonia can also develop, particularly in bedridden patients after a fracture.
Deep Vein Thrombosis (DVT), a blood clot in a deep vein (commonly in the legs), is another potential cause of fever after a fracture. Fractures increase DVT risk due to immobilization, damage to blood vessels, and the body’s increased clotting activity in response to injury. While DVT symptoms primarily include swelling, pain, and warmth in the affected limb, some individuals may develop a low-grade fever.
Fat Embolism Syndrome (FES) is a serious complication after fractures of long bones (e.g., thigh or shin). When large bones break, fat globules from the bone marrow can enter the bloodstream, potentially obstructing blood vessels in the lungs or brain. FES symptoms appear 12 to 72 hours post-injury and can include fever, rapid breathing, mental confusion, and a characteristic pinpoint rash.
Severe, complex, or multiple fractures can trigger Systemic Inflammatory Response Syndrome (SIRS) due to extensive tissue damage. While not always associated with fever, SIRS involves a systemic release of inflammatory mediators that can elevate body temperature. Additionally, a fever could be unrelated to the fracture, stemming from another concurrent illness or injury like the flu.
When to Seek Medical Attention
Any fever after a broken bone requires immediate medical evaluation. It could indicate a serious complication like infection, DVT, or FES, requiring timely diagnosis and treatment. Delaying medical attention can lead to more severe health issues.
Contact a doctor or seek emergency care, especially if the fever is high, persistent, or accompanied by other concerning symptoms. These additional signs include worsening pain, increased redness or warmth around the fracture site, pus draining from a wound, shortness of breath, or confusion. Professional medical assessment is important to determine the cause of the fever and ensure appropriate management, avoiding self-diagnosis or delayed help.