S92.316 Nondisplaced fracture of first metatarsal bone, unspecified foot

Name of the Condition

• Nondisplaced fracture of first metatarsal bone, unspecified foot
• ICD-10 Code: S92.316

Summary

A nondisplaced fracture of the first metatarsal bone is a break in the long bone at the base of the big toe where the bone fragments remain in their normal alignment. This type of injury typically results from trauma, such as a direct impact or twisting force, and is localized to the unspecified foot. The first metatarsal is the largest and most weight-bearing of the metatarsal bones, making it susceptible to injury during activities that stress the foot.

Causes

Direct trauma to the foot, such as dropping a heavy object, a sports injury, or a fall, is the most common cause. Repetitive stress from activities like running or jumping can also lead to stress fractures over time. Twisting the foot or sudden impact may result in a fracture, particularly in high-impact scenarios.

Risk Factors

• Participation in high-impact sports (e.g., basketball, soccer)
• Wearing improper or non-supportive footwear
• Conditions that weaken bones, such as osteoporosis
• Advanced age, which may reduce bone density and balance
• Previous foot injuries or fractures

Symptoms

• Pain and tenderness at the base of the big toe
• Swelling and bruising around the affected area
• Difficulty bearing weight or walking on the injured foot
• Possible deformity if the fracture is displaced (though less common in nondisplaced cases)

Diagnosis

A healthcare provider will perform a physical examination to assess pain, swelling, and range of motion. Imaging studies, such as X-rays, are typically used to confirm the fracture and determine if it is nondisplaced. Additional tests may be ordered if there is suspicion of associated injuries or complications.

Treatment Options

Treatment for a nondisplaced fracture often involves immobilization with a cast, boot, or splint to allow the bone to heal. Pain management may include over-the-counter or prescription medications. Weight-bearing restrictions are common initially, with gradual return to normal activity as healing progresses. Physical therapy may be recommended to restore strength and mobility.

Prognosis and Follow-Up

Most nondisplaced fractures of the first metatarsal heal well with proper immobilization and rest. Full recovery typically occurs within 6–8 weeks, though this may vary based on the individual and injury severity. Follow-up appointments are important to monitor healing and adjust treatment as needed. Long-term outcomes are generally favorable, with most patients regaining normal function.

Complications

While rare, complications can include delayed healing, nonunion (failure to heal), or malunion (healing in an abnormal position). Infection may occur if the skin is broken, and chronic pain or arthritis in the big toe joint is possible in some cases. Nerve or blood vessel damage is uncommon but may occur with severe trauma.

Lifestyle & Prevention

Wearing supportive footwear, especially during high-impact activities, can reduce the risk of injury. Maintaining bone health through a balanced diet rich in calcium and vitamin D may help prevent fractures. Avoiding repetitive stress on the foot and using proper techniques during sports or exercise can also lower risk. Gradual conditioning and warm-up exercises are recommended before physical activity.

When to Seek Professional Help

Seek medical attention if you experience severe pain, swelling, or bruising after a foot injury, or if you cannot bear weight on the affected foot. Immediate care is needed if the foot appears deformed, or if there are signs of infection (e.g., redness, warmth, or pus). Persistent pain or difficulty walking after an injury should also prompt a healthcare evaluation.

Tips for Medical Coders

When coding S92.316, ensure the documentation specifies a nondisplaced fracture of the first metatarsal bone in an unspecified foot. Verify that the injury is not displaced or associated with other foot injuries, as this may require a different code. Confirm the absence of laterality (right/left) to justify the "unspecified foot" designation. Accurate clinical documentation is essential to support the code selection and avoid denials.