Which complication of fractures is associated with persistent pain and limited function despite appropriate treatment?

: Stress fractures are small, hairline cracks in the bone that occur due to repetitive stress or overuse. They typically present with a gradual onset of localized pain that worsens with activity.

a. Severe pain and deformity: Severe pain and deformity are more commonly seen in acute fractures resulting from trauma or high-impact injuries, not stress fractures.
b. Sudden onset of swelling and bruising: Sudden onset of swelling and bruising is more indicative of acute fractures, not stress fractures.
d. Inability to bear weight on the affected limb: Inability to bear weight may be present in some fractures, but it is not a specific characteristic of stress fractures.

Nonunion occurs when the fractured bone fails to heal and fuse together despite appropriate treatment. It is associated with persistent pain and limited function.

b. Malunion: Malunion refers to a fracture that heals in an incorrect position or alignment, but it may or may not cause persistent pain and limited function.
c. Delayed union: Delayed union refers to a fracture that takes longer than usual to heal but eventually heals properly. It is not specifically associated with persistent pain and limited function.
d. Osteomyelitis: Osteomyelitis is a bone infection that can develop as a complication of fractures, but it may or may not cause persistent pain and limited function, depending on its severity and treatment response.