This lecture introduces biphasic osteoarticular SPECT scintigraphy (BOSS) as an advanced extension of conventional bone scanning, with a focus on its scientific basis, technical implementation, and clinical impact. The session explains how early-phase SPECT captures inflammatory and perfusion-related processes that may be missed or underestimated on delayed imaging alone, drawing parallels between bone tracers and contrast agents. Through practical examples and pattern-based interpretation (BOSS patterns A, B, and C), the lecture demonstrates how early and delayed SPECT/CT can be integrated to accurately localize pain generators, differentiate inflammatory from osseous pathology, and streamline patient management.

Learning Objectives

By the end of this lecture, participants will be able to:

• Define biphasic osteoarticular SPECT scintigraphy and explain its pharmacokinetic and pathophysiologic basis.
• Describe optimal acquisition protocols for early- and delayed-phase SPECT/CT in musculoskeletal imaging.
• Recognize and apply the BOSS patterns (A, B, and C) to correlate inflammatory and osseous findings.
• Differentiate common periarticular pathologies (e.g., enthesitis, synovitis, bursitis, infection) using early-phase SPECT.
• Integrate early-phase SPECT into routine clinical workflows to improve diagnostic confidence and reduce delays in care.