Proximal/Superior Attachment
- Base of 3rd Metacarpal - Anteriorly between the 2nd and 3rd Metacarpal
- Base of 4th Metacarpal - Anteriorly between the 3rd and 4th Metacarpal
- Base of 5th Metacarpal - Anteriorly between the 4th and 5th Metacarpal
Distal/Inferior Attachment
- Base of 2nd Metacarpal - Anteriorly between the 2nd and 3rd Metacarpal
- Base of 3rd Metacarpal - Anteriorly between the 3rd and 4th Metacarpal
- Base of 4th Metacarpal - Anteriorly between the 4th and 5th Metacarpal