title: SPECT-CT compared with conventional imaging modalities for the assessment of the varus and valgus malaligned hindfoot.
abstract: The combined single-photon emission computed tomography and conventional computed tomography (SPECT/CT) technique has increased the sensitivity and specificity of bone scans. We examined the value of using SPECT/CT for the assessment of coronal plane hindfoot deformities. Twenty-seven patients with varus (11 patients) or valgus (16 patients) malalignment of the hindfoot were assessed using radiography, conventional CT, bone scintigraphy, and SPECT/CT. The amount of deformity, stage of osteoarthritis, and level of activation on bone scans and SPECT/CT were measured. Activation was assessed in 12 regions of interest. The stage of osteoarthritis seen on plain radiographs correlated significantly with the level of activation detected on bone scans (p < 0.05). No correlation was observed between the amount of deformation and activity, and between bone scan activation and signs of osteoarthritis on CT scans. The varus malaligned ankles showed higher radioisotope uptake in the medial areas, while the valgus malaligned ankles showed increased uptake in the lateral areas (p < 0.05). SPECT/CT may be a valuable tool for the assessment and staging of osteoarthritis. Our findings underline the adverse effects of coronal plane deformity of the hindfoot. In addition, results from this study provide useful information for future basic research on coronal plane deformity of the hindfoot and for determining appropriate surgical approaches.
authors.affiliation: Department of Orthopedic Surgery, Kantonsspital Liestal, Liestal, Switzerland. markus.knupp@ksli.ch
authors.forename: Markus
authors.initials: M
authors.lastname: Knupp
authors.forename: Geert I
authors.initials: GI
authors.lastname: Pagenstert
authors.forename: Alexej
authors.initials: A
authors.lastname: Barg
authors.forename: Lilianna
authors.initials: L
authors.lastname: Bolliger
authors.forename: Mark E
authors.initials: ME
authors.lastname: Easley
authors.forename: Beat
authors.initials: B
authors.lastname: Hintermann
mesh_terms: D000328:Adult; D000368:Aged; D000843:Ankle Joint / Q000000981:diagnostic imaging*; D005260:Female; D005530:Foot Deformities / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods