Shoulders with bony Bankart lesions show bone fragment absorption

Shoulders with bony Bankart lesions show bone fragment absorption

Bone fragment absorption in shoulders with bony Bankart lesions after traumatic anterior shoulder instability correlated with the time after trauma, according to results of this study by Japanese researchers.

“Bone fragment absorption was seen in all of the shoulders with bony Bankart lesions. Most bone fragments showed severe absorption within 1 year after the primary traumatic episode,” Shigeto Nakagawa, MD, PhD, and colleagues from Osaka, Japan, wrote in the study abstract. “Before arthroscopic Bankart repair, not only glenoid defects but also bone fragment absorption should be assessed.”

Nakagawa and colleagues prospectively analyzed 163 shoulders using CT scans. They found that 55 shoulders had no glenoid defects, 16 shoulders had erosions, and 92 shoulders had glenoid defects, according to the abstract. The average glenoid defect size was 7.9% at less than 1 year, 10.7% between 1 year and 2 years and 11.3% after 2 years. 

The results showed some bone fragment absorption in all shoulders with glenoid defects: <50% absorption was seen in 32 shoulders, >50% absorption in 45 shoulders and 100% absorption in 15 shoulders. In shoulders scanned at less than 1 year, the extent of absorption was 51.9%. Between 1 year and 2 years, the extent of absorption was 65.3%, while in shoulders scanned after 2 years the extentof absorption was 70%, according to the abstract. 

Nakagawa S. Am J Sports Med. 2013. doi:10.1177/0363546513483087