Osteitis of the end of the tuber calcanei may be seen after traumatic injury and subsequent infection. This most often occurs after a kick from another horse or when the horse kicks a fixed object, such as a wall. Osteitis causes moderate to severe lameness, cellulitis, and tarsal tenosynovitis. Concurrent sepsis of the calcaneal bursae, tarsocrural joint, or tarsal sheath may occur. Diagnosis is confirmed by radiography; however, radiologic signs of focal osteolysis may take days or weeks to develop and, therefore, sequential radiographs are recommended. Treatment involves debridement of any bony lesions, endoscopic lavage of infected synovial cavities, and wound debridement combined with appropriate local and systemic antimicrobial therapy.