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We thank Wee(1) for his letter and agree that ultrasonography is routinely used to evaluate musculoskeletal disorders and widely employed in many institutions, including ours. There is no debate that ultrasonography has similar specificity and sensitivity to magnetic resonance (MR) imaging for many musculoskeletal conditions, often complementing each other.(2)
However, our article was not focused on a discussion about MR imaging compared to ultrasonography or the strengths of either modality. Rather, it discussed Baxter’s neuropathy as a cause of refractory heel pain along with various differentials to consider. In this case, MR imaging was utilised to obtain the diagnosis and is a widely accepted first-line modality for this specific condition.(3,4) Literature is scarce on the sensitivity and operator consistency of utilising ultrasonography to diagnose Baxter’s neuropathy. The cited cadaveric study(5) has limited applicability to live patients; although it may be true of a highly skilled musculoskeletal ultrasonography operator, this does not reflect daily practice in many institutions worldwide. We therefore respectfully disagree that ultrasonography should be the first-choice modality for imaging Baxter’s neuropathy. Additionally, both MR imaging and ultrasonography were mentioned as equal choices to diagnose plantar fibromatosis in our discussion.
Electrodiagnostic testing is unnecessary when the history, clinical examination and MR images confirm Baxter’s neuropathy. Ultrasonography has limited sensitivity in early gout,(6) as in the case shown, while dual-energy computed tomography was impartially mentioned as an effective tool for problem-solving cases of incipient gout that may be a diagnostic conundrum for the clinician.
1. Wee TC. Comment on: Clinics in diagnostic imaging (205). Singapore Med J 2020; 61:339-40.
2. Jacobson JA. Musculoskeletal ultrasound and MRI: which do I choose? Semin Musculoskelet Radiol 2005; 9:135-49.
3. Moreno García MS, Del Río-Martínez PS, Yanguas Barea N, Baltanás Rubio P. Hindfoot pain: Baxter neuropathy. Reumatol Clin 2017; 13:123.
4. Dirim B, Resnick D, Ozenler NK. Bilateral Baxter's neuropathy secondary to plantar fasciitis. Med Sci Monit 2010; 16:CS50-53.
5. Presley JC, Maida E, Pawlina W, et al. Sonographic visualization of the first branch of the lateral plantar nerve (Baxter nerve): technique and validation using perineural injections in a cadaveric model. J Ultrasound Med 2013; 32:1643-52.
6. Ogdie A, Taylor WJ, Neogi T, et al. Performance of ultrasound in the diagnosis of gout in a multicenter study: comparison with monosodium urate monohydrate crystal analysis as the gold standard. Arthritis Rheumatol 2017; 69:429-38.