[Foot and ankle tumours : Part II: Malignant bone tumours and soft tissue tumours of the foot with differential diagnostic hints]

Nuclear Medicine for the Orthopedic Foot and Ankle Surgeon

Nuclear medicine has been widely applied as a diagnostic tool for orthopedic foot and ankle pathology. Although its indications have diminished with improvements in and the availability of magnetic resonance imaging, nuclear medicine still has a significant and valuable role. The present article offers a comprehensive and current review of the most common nuclear imaging modalities for the orthopedic foot and ankle surgeon. Methods discussed include bone scintigraphy, gallium citrate scintigraphy, labeled-leukocyte scintigraphy, and single-photon emission computed tomography (SPECT). We review the indications and utility of these techniques as they pertain to specific foot and ankle conditions, including osteomyelitis, stress fractures, talar osteochondral lesions, complex regional pain syndrome, oncology, plantar fasciitis, and the painful total ankle arthroplasty. We conclude with a discussion of our approach to nuclear medicine with illustrative cases. Level of Evidence: Level V, expert opinion.

Prevalence of bone marrow edema in a study population with foot and/or ankle pain

Bone marrow edema (BME) is an imaging diagnosis defined by an abnormal accumulation of intraosseous interstitial fluid within a bone on magnetic resonance imaging (MRI) investigation. The aim of this study was to determine the prevalence of BME in patients with foot and/or ankle pain studied using MRI. This was a retrospective observational work on patient cases and controls studied through MRI of the foot and/or ankle at our Foot and Ankle Unit (FAU). An analytical statistical analysis and a multivariate analysis were performed to eliminate possible confounding factors. 1950 foot and/or ankle MRI cases were reviewed, of which 451 presented bone edema (23% prevalence). The average patient age was 51.8 (range, 7-87); the talus bone was most frequently affected: post-traumatic in 43.5% of cases, degenerative in 34.7% and there was no specific cause identified in 6.3% (these cases were termed 'idiopathic'). With regards to risk factors, in the case of gender, the odds ratio (OR) of men suffering bone oedema was 1.5 times higher than that of women (P = 0.003); for immunosuppression the OR was 3.4 times higher (P = 0.001); while among those with a smoking habit it was 0.59 (P = 0.001), meaning that after ruling smoking out as a possible confounding factor, it was, in fact, revealed to be a protective factor. The prevalence of bone edema in MRI in patients with foot and/or ankle pain was 23%. The average patient was male, aged approximately 50, with traumatic or degenerative origin talus bone oedema. Level of Evidence: Level IV, revision observational study.