A 5-year-old boy is brought to the office due to left wrist pain lasting a day. His mother states that he refuses to use the left hand because of the pain. The patient has no previous medical conditions and is up to date with immunizations. He consumes a balanced diet. Vital signs and growth parameters are within normal limits for his age. On physical examination, the patient holds the left arm against his body. There is tenderness of the left wrist with no visible deformity. When instructed, the patient moves all fingers except the left thumb. Radiograph of the left forearm is shown in the image below: Which of the following is the most likely cause of this patient's symptoms?

Question

A 5-year-old boy is brought to the office due to left wrist pain lasting a day.  His mother states that he refuses to use the left hand because of the pain.  The patient has no previous medical conditions and is up to date with immunizations.  He consumes a balanced diet.  Vital signs and growth parameters are within normal limits for his age.  On physical examination, the patient holds the left arm against his body.  There is tenderness of the left wrist with no visible deformity.  When instructed, the patient moves all fingers except the left thumb.  Radiograph of the left forearm is shown in the image below:  Which of the following is the most likely cause of this patient's symptoms?

Quizplus · Accepted Answer

11ec25c8_d86f_df81_bc81_5311daba6945_MD0003_00 Forearm fractures are common in children and most frequently involve the distal radius and/or ulna after a fall onto an outstretched hand. Young children (age <10) have porous bone, which allows for compression of the distal metaphyseal cortex after an injury. This results in a buckle fracture, which is characterized by the cortices bending (ie, buckling) without breaking and becoming displaced (as typically occurs in a complete fracture); for this reason, a buckle fracture is considered a stable and incomplete fracture. complete fracture Buckle fractures present with pain and tenderness over the fracture site. Wrist range of motion may be intact or slightly limited (ie, impaired thumb movement due to radial injury), and swelling is often absent. X-ray is required to confirm the diagnosis and exclude a greenstick or complete fracture. Rather than a fracture line, a cortical bulge is visualized. greenstick Treatment involves pain control and prevention of reinjury (eg, splint placement). Most buckle fractures heal within a few weeks without complication. (Choice A) In children, avascular bone necrosis most commonly involves the hip (Legg-Calvé-Perthes disease) and presents with chronic joint pain and decreased range of motion. X-ray findings with prolonged disease include bony fragmentation and sclerosis. A distal forearm fracture with a cortical bulge is most consistent with a buckle fracture. X-ray (Choice B) Dietary vitamin D deficiency can lead to impaired bone mineralization (rickets), which can result in bowing of the long bones and fraying/cupping of the distal radius and ulna with widening of the wrist growth plate. These findings are not seen on this patient's x-ray. fraying/cupping (Choice C) Hematogenous osteomyelitis, a bone infection, typically presents with fever and bony tenderness, swelling, and erythema. X-ray is often normal in the first few days to weeks of symptoms but later shows soft tissue swelling and periosteal elevation. periosteal elevation (Choice E) Osteosarcoma is the most common primary bone malignancy in children and typically presents with localized bone pain and a soft tissue mass. Characteristic x-ray findings include Codman triangle and a sunburst pattern indicating a periosteal reaction, neither of which is seen in this patient. x-ray findings Educational objective: Buckle fractures are common in children and typically occur at the distal radius and/or ulna due to a fall onto an outstretched hand. X-ray is diagnostic and shows bulging of the bony cortex. References: Buckle fractures of the distal radius in children. (http://www.ncbi.nlm.nih.gov/pubmed/26976961)

A 5-Year-Old Boy Is Brought to the Office Due to Left