Orthopaedic surgeons frequently use aspirations and injections to both diagnose and treat disorders of the lower extremity. Comprehensive knowledge of regional anatomy, procedural indications, and appropriate techniques are essential. Clinicians must be well versed in a range of musculoskeletal aspiration and injection techniques, including patient positioning, equipment needs, injectable solutions, aspirate analysis, and potential complications. Safe and effective aspiration and injection techniques for the lower extremity, including the hip, knee, foot, and ankle, are reviewed. Image guidance modalities include fluoroscopy, ultrasonography, CT, and MRI.