The way I differentiate between the two is that with 23130, the target is the bony resection, the ligament needs to be taken down on approach. The 23130 is the target. Usually, the 23415 is just a release of the ligament, no bony work, or minimal bony work, Is this correct? The doctor did the following:

The left upper extremity and hemithorax were prepped and draped in a sterile fashion and proposed oblique incision site of the lateral aspect of the acromion heading towards the coracoid was injected with 1% lidocaine with epinephrine for hemostasis. A #10 blade was used to cut down the underlying subcutaneous tissue to obtain access to clavipectoral fascia. the deltoid on approach was used using a Bovie electrocautery to elevate the deltoid tendon of the acromion and lateral aspect of the clavicle. The type II acromion, there was some spurring anteriorly and the anterior aspect was resected with the oscillating saw after Darrach retractor was inserted to protect the underlying rotator cuff. the undersurface was palpated and numerous spurs were felt and there was significant thickening and this was resected with the oscillating saw followed by use of the oscillating footrest to smooth this down to a stabilize edge. A gloved finger was inserted, no ruther spurring was noted.

Patient has impingement syndrome, degenerative arthritis & adhesive capsulitis.