MG-1treated group: Patients those who underwent arthroscopic Bankart repair for glenohumeral instability using MG-1

To evaluate Bone Hole Condition with score based on CT images. CT images are evaluated and scored by three evaluators who are MDs and independent of this study director.

Definitions of the score are described as below.

• Type 1: Opened or enlarged
• Type 2: Slightly closed (<50%)
• Type 3: Almost closed (>=50%)
• Type 4: Completely closed

To evaluate Ossification with score based on CT images. CT images are evaluated and scored by three evaluators who are MDs and independent of this study director.

Definitions of the score are described as below.

• Type 1: Little or no ossification
• Type 2: Ossification fills some of the anchor site that is discontinuous or with a wide lucent rim
• Type 3: Ossification fills most of the anchor site with a thin lucent rim. This area's density is consistent with cancellous bone
• Type 4: Ossification fills the anchor site completely with an indistinct border between the anchor site and the adjacent cancellous bone

To evaluate the Japan Shoulder Society Shoulder Instability Score (JSS-SIS) and Rowe Score at 12 weeks after surgery

JSS-SIS Score (subscales are summed, higher values represent a better outcome):

• Pain (0 to 20)
• Function (0 to 20)
• Range of Motion (0 to 20)
• Evaluation of X-ray findings (0 to 10)
• Stability (0 to 30)

Rowe Score (subscales are summed, higher values represent a better outcome):

• Stability (0 to 50)
• Motion (0 to 20)
• Function (0 to 30)