CPT Code for Left Shoulder Hemiarthroplasty
The CPT code for a left shoulder hemiarthroplasty is 23470.
This code applies regardless of laterality (left or right shoulder), as CPT codes do not distinguish between sides—laterality is documented separately in the medical record and billing modifiers.
Important Context About This Procedure Code
CPT 23470 specifically designates hemiarthroplasty of the shoulder, which involves replacement of only the humeral head component without glenoid resurfacing 1. This code has been in use since at least 2000 and remains the standard billing code for this procedure.
When Hemiarthroplasty is Typically Indicated
Hemiarthroplasties are most commonly performed in specific clinical scenarios 2:
- Comminuted proximal humerus fractures (acute trauma cases)
- Osteoarthritis limited to the humeral head (glenoid cartilage preserved)
- Deficient glenoid bone stock (insufficient bone for glenoid component)
- Patients with significant medical comorbidities requiring shorter operative time
- Humeral head osteonecrosis
- Large Hill-Sachs deformities
Clinical Caveat
While 23470 is the correct code for hemiarthroplasty, current evidence favors total shoulder arthroplasty (CPT 23472) over hemiarthroplasty for advanced glenohumeral osteoarthritis due to superior clinical outcomes 3, 2. The 2010 AAOS guideline provided a moderate-rated recommendation for TSA rather than hemiarthroplasty in osteoarthritis patients 3.
Reimbursement Considerations
Inflation-adjusted Medicare reimbursement for CPT 23470 has declined substantially from $2,419.81 in 2000 to $1,192.43 in 2025—a reduction of approximately 51% 1. This represents a significant decrease in real-dollar physician compensation for this procedure over the past 25 years.
Documentation Requirements
No modifier is needed to specify left vs. right shoulder. Standard documentation should include:
- Laterality clearly stated in operative report
- Indication for hemiarthroplasty rather than total shoulder arthroplasty
- Any complexity factors that might justify additional modifiers (such as the 22-modifier for increased procedural complexity, though reimbursement rates for this modifier are low at approximately 26.5% overall) 4