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

question 137

Multiple Choice

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. $A 52-year-old man comes to the clinic for follow-up of a nonhealing wound on his right leg. Eight months ago, the patient had an open fracture of his right tibia due to a motorcycle accident. His injury was surgically treated, and for 2 weeks afterward he had occasional fevers that resolved with a course of antibiotics. For the past month, he has had clear drainage from the wound, which has required daily changing of the dressing. The patient has type 2 diabetes mellitus, which is treated with insulin, and hypertension. On examination, there is a chronic wound, and the overlying dressing contains a scant amount of serosanguinous fluid. There is pain at the fracture site and the patient is unable to bear full weight on the leg. Dorsiflexion of the ankle causes minimal discomfort. Pedal pulses are palpable. X-ray of the leg is shown in the exhibit. Which of the following is the best next step in the management of this patient's condition? A) Below-the-knee amputation B) CT angiogram of the extremity C) Immediate surgical fixation of the tibia D) Silver sulfadiazine cream and sterile dressing application E) Split-thickness skin graft to the soft tissue defect F) Surgical debridement and bone biopsy$ Which of the following is the best next step in the management of this patient's condition?

Definitions:

Ribosomal Subunit

A structural component of ribosomes, which comes in two sizes (large and small), necessary for protein synthesis in cells.

Prokaryotic Translation

The process by which mRNA is decoded by a ribosome to produce a specific protein in prokaryotes, organisms without a nucleus.

Initiation Complex

A complex of proteins and RNA that forms on mRNA to begin the process of translating RNA into a polypeptide chain in the cell.

Nonsense Mutation

A base-pair substitution mutation that results in an amino acid–specifying codon being changed to a termination (stop) codon; when the abnormal mRNA is translated, the resulting protein is usually shortened and nonfunctional. Compare with missense mutation.