Musculoskeletal Ultrasound for Preoperative Imaging of the Plantar Plate

The purpose of this study was to prospectively compare preop- erative findings on musculoskele- tal ultrasound evaluation to observed intraoperative findings for patients undergoing surgical correction of plantar plate tears. Fifty consecutive patients with forefoot pain and a sus- pected unilateral plantar plate tear at the second metatarsophalangeal (MTP) joint were identified. The same examiner performed a 2-plane (longi- tudinal and transverse) musculoskel- etal ultrasound on the painful second MTP joint. The contralateral second MTP joint was used for comparison. Longitudinal ultrasound images were graded as "torn" or "intact." Transverse ultrasound images were used to local- ize the suspected pathology. Results of the ultrasound were compared with observed intraoperative pathology. Forty-five plantar plate tears were iden- tified intraoperatively. Longitudinal ultrasound images correctly identi- fied 40 plantar plate tears. The longi- tudinal ultrasound had a sensitivity of 91.1%, a specificity of 25%, a positive predictive value of 91.1%, and a nega- tive predictive value of 25%. Transverse ultrasound images identified 36 plan- tar plate tears correctly localizing only 19 tears. Musculoskeletal ultrasound has been widely used to identify and localize pathology in many soft tis- sue structures. Whereas the longitudi- nal ultrasound images were useful in identifying plantar plate tears, the same cannot be said about the ability to localize the tear on the transverse ultra- sound images. Therefore, ultrasound may not be as good an imaging modal- ity as magnetic resonance imaging for identification and localization of plantar plate pathology. Levels of Evidence: Diagnostic, Level II