Table 1 Radiographic classification of glenohumeral osteoarthritis according to Koss et al⁶.

Grade		Stage		Joint narrowing		Osteophytes		Joint sclerosis		Cysts
Grade 0		Normal		No joint space narrowing		No osteophytes		No sclerosis		No cysts
Grade I		Minimal changes		Less than 1 mm space narrowing		No osteophytes		Slight sclerosis		No cysts
Grade II		Moderate changes		Narrowing less than or equal to 2 mm		Mild‐to‐moderate osteophytes		Moderate sclerosis		No cysts
Grade III		Severe changes		Severe joint space narrowing		Abundant osteophytes		Severe sclerosis		Cyst formation