A 52-year-old man comes to the clinic for follow-up of a nonhealing wound on his right leg. Eight months ago, the patient had an open fracture of his right tibia due to a motorcycle accident. His injury was surgically treated, and for 2 weeks afterward he had occasional fevers that resolved with a course of antibiotics. For the past month, he has had clear drainage from the wound, which has required daily changing of the dressing. The patient has type 2 diabetes mellitus, which is treated with insulin, and hypertension. On examination, there is a chronic wound, and the overlying dressing contains a scant amount of serosanguinous fluid. There is pain at the fracture site and the patient is unable to bear full weight on the leg. Dorsiflexion of the ankle causes minimal discomfort. Pedal pulses are palpable. X-ray of the leg is shown in the exhibit. Which of the following is the best next step in the management of this patient's condition?

Question

A 52-year-old man comes to the clinic for follow-up of a nonhealing wound on his right leg.  Eight months ago, the patient had an open fracture of his right tibia due to a motorcycle accident.  His injury was surgically treated, and for 2 weeks afterward he had occasional fevers that resolved with a course of antibiotics.  For the past month, he has had clear drainage from the wound, which has required daily changing of the dressing.  The patient has type 2 diabetes mellitus, which is treated with insulin, and hypertension.  On examination, there is a chronic wound, and the overlying dressing contains a scant amount of serosanguinous fluid.  There is pain at the fracture site and the patient is unable to bear full weight on the leg.  Dorsiflexion of the ankle causes minimal discomfort.  Pedal pulses are palpable.  X-ray of the leg is shown in the exhibit.  Which of the following is the best next step in the management of this patient's condition?

Quizplus · Accepted Answer

11ec25c8_d96f_0088_bc81_1faa2bad6907_MD0003_00 This patient has a tibial fracture complicated by nonunion, defined as failure of a fracture to achieve radiographic or clinical evidence of union within an adequate time frame (eg, 6 months for long bone shaft fractures). Risk factors for nonunion include impaired blood flow (eg, smoking, arterial atherosclerosis), certain medications (eg, systemic glucocorticoids), metabolic disorders (eg, diabetes, hypothyroidism), and infection (eg, osteomyelitis). Acute osteomyelitis typically presents with local pain, erythema, and fever over a few days or weeks. However, if the bony infection is not completely eradicated, it can lead to a chronic, indolent infection (ie, chronic osteomyelitis) with necrosis and fragmentation (sequestrum) of the bone. Chronic osteomyelitis is a common complication of high-velocity tibial fractures because the bony fragments are often exposed and the blood supply may be disrupted by trauma. A sinus tract with a persistently draining wound, as in this patient, strongly suggests chronic osteomyelitis. Intermittent pain and swelling may occur; however, fever and leukocytosis are usually less prominent. The diagnosis is suggested by this patient's x-ray, which shows fragmentation of the bone and ragged, irregular fracture lines. Erythrocyte sedimentation rate and C-reactive protein are often elevated. Open bone biopsy is preferred over percutaneous aspiration for microbiologic sampling; culture of sinus tracts generally has poor sensitivity and specificity. Surgical debridement of the infected and necrotic bone is required for definitive management. (Choice A) Amputation is often required for diabetic patients with ulcers that do not heal due to impaired blood flow. However, this patient's sinus tract is caused by chronic osteomyelitis, and aggressive treatment of the infection may allow limb salvage. (Choice B) A CT angiogram to assess vascular status is indicated for patients with fractures associated with absent distal pulses. Although violent fractures can cause disruption of the tibial blood flow despite palpable distal pulses, other vascular signs (eg, pallor or mottling of the skin, decreased sensation) are usually present. (Choice C) Surgical fixation with insertion of additional hardware without first eliminating the infection would likely result in infection of the hardware. Once the infection is fully eradicated, additional orthopedic fixation could be considered. (Choices D and E) Silver sulfadiazine and skin grafting are often used for burn wounds. These superficial interventions would not treat the deep infection. Educational objective: Chronic osteomyelitis may lead to fracture nonunion. Common symptoms include intermittent pain and swelling and sinus tract formation. Open bone biopsy is recommended for microbiologic assessment, and treatment requires surgical debridement of the infected and necrotic bone. References: Osteomyelitis. (http://www.ncbi.nlm.nih.gov/pubmed/28483044) Antibiotics for treating chronic osteomyelitis in adults. (http://www.ncbi.nlm.nih.gov/pubmed/24014191)

A 52-Year-Old Man Comes to the Clinic for Follow-Up of a Nonhealing