The Utility of Sulfur Colloid Imaging to Differentiate Charcot's Neuroarthropathy from Osteomyelitis: A Case Study.

Charcot's neuroarthropathy and osteomyelitis can have similar initial presentations. The ability to differentiate between the two pathologic conditions is essential, as each requires different treatment. We present a case of a 53-year-old woman with pain, swelling, and warmth in her left first metatarsophalangeal joint and first tarsometatarsal joint. Radiographs showed comminuted fractures at the base of the first metatarsal. Osteomyelitis was suspected by the primary team based on physical findings and a history of previous first metatarsophalangeal joint arthrodesis. A triphasic bone scan and an indium white blood cell scan were positive for osteomyelitis. The podiatric medical team was suspicious for possible Charcot's neuroarthropathy based on physical findings and uncontrolled blood glucose levels at the time of her previous arthrodesis. A sulfur colloid scan was performed and compared with an indium scan, which showed no evidence of osteomyelitis. This case demonstrates the usefulness of sulfur colloid imaging compared with an indium white blood cell scan to differentiate osteomyelitis from Charcot's neuroarthropathy. This case also highlights the importance of using clinical judgment to make the correct diagnosis.

Concomitant Achilles Tendon Lengthening with Transmetatarsal Amputation for the Prevention of Late Forefoot Ulceration.

BACKGROUND: Late development of forefoot ulcers is a common finding after transmetatarsal amputation (TMA). The primary aim of this study was to examine whether concomitant prophylactic Achilles tendon lengthening (ATL) was associated with a reduction in the incidence of forefoot ulcers postoperatively. METHODS: A retrospective chart review was performed by 2 authors to identify patients who underwent TMA over a period of 5.5 years from January 1, 2015, through July 31, 2020. They identified 110 feet in 107 patients; the 83 patients (85 feet) who had ≥120 days of follow-up were used for the study. Follow-up was performed with telephone calls (80 patients) or during the last office visit (3 patients). Those who were contacted by telephone were asked if they developed an ulcer after healing from the original surgery. Mean follow-up time was 672 ± 258 days for the 30 feet with concomitant Achilles lengthening and 663 ± 434 days for the 55 feet without Achilles lengthening. Demographic data were analyzed for association with late development of forefoot ulceration. RESULTS: Eighty-five feet were included in the analysis. Late forefoot ulcers developed in 35% of feet that had a TMA alone (n = 55) compared with 3% of feet who received a concomitant ATL (n = 30; p < 0.001); the 2 groups had similar mean follow-up times. Mean time to ulcer development was 587 ± 420 days in the 19 patients without Achilles lengthening. Of the patients who developed late forefoot ulcers, 47% also developed osteomyelitis, and 16% went on to proximal amputation. Patients who developed forefoot ulcers were younger (55 ± 12 versus 63 ± 11 years of age; p = 0.006) than those who did not. CONCLUSIONS: ATL at the time of TMA is associated with a reduction in the risk of later development of forefoot ulcers, especially in younger patients. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.