Stump elongation of the upper extremity through bone graft to increase residual limb length for prosthetic fitting or functional improvement.

Verified May 8, 2026 · 5 sources ↓

Medicare: $1,137.30
Total RVUs: 34.05
Global, days: 90
Region: Elbow

Drawn from CMSEmednyAAOS

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 5 cited references ↓

Operative note must explicitly identify the procedure as stump elongation, not revision or re-amputation
Document graft type (autogenous vs. allograft) and harvest site if autogenous
Record fixation method used to secure the graft and achieve elongation
Quantify the amount of length gained in the residual limb
Document medical necessity — typically prosthetic fitting failure, inadequate lever arm, or functional deficit from short residual limb
Prior amputation history including level, laterality, and date of original amputation

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 24 Unrelated E/M during global 51 Multiple procedures 57 Decision for surgery 58 Staged or related 59 Distinct service 62 Co-surgeons 74 Discontinued post-anesthesia 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 24935 covers stump elongation of the upper extremity — a surgical procedure in which bone graft (typically autogenous) is used to lengthen the residual limb following a prior amputation through the humerus or at the elbow level. The goal is to improve prosthetic fit, socket suspension, or lever-arm mechanics. This is a distinct procedure from re-amputation (24930) and from secondary closure or scar revision (24925); code selection depends on what is actually being performed, not just that the surgeon returned to a prior amputation site.

The 90-day global period means all routine post-op management through day 90 is bundled. If the patient develops a complication requiring a return to the OR for a related procedure during that window, bill with modifier 78. A staged subsequent procedure planned from the outset — such as a delayed bone graft stage — uses modifier 58 and resets the global clock. An unrelated procedure in the global period uses modifier 79.

Documentation must establish that the procedure performed was stump elongation specifically, not revision, re-amputation, or wound management. Operative notes should describe graft harvest site, graft type, fixation method, and the amount of length gained. Vague operative notes that don't distinguish elongation from revision are the primary audit trigger for this code.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	16.04
Practice expense RVU	14.6
Malpractice RVU	3.41
Total RVU	34.05
Medicare national rate	$1,137.30
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$1,137.30
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI G2) Ambulatory surgical center (freestanding)	$3,695.53

Common denial reasons

The recurring reasons claims for CPT 24935 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Operative note describes revision or wound debridement rather than true stump elongation with bone graft
Medical necessity not established — no documentation of prosthetic fitting failure or functional limitation from residual limb length
Incorrect code selected — 24930 (re-amputation) or 24925 (scar revision) billed when elongation was performed
Missing laterality modifier (LT or RT) required by payer
Global period conflict — procedure billed during a prior amputation's 90-day global without appropriate modifier (58, 78, or 79)

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01What is the difference between CPT 24935 and CPT 24930?

24930 is re-amputation — removing additional bone to create a cleaner or more functional stump. 24935 is stump elongation — adding bone graft to increase residual limb length. Opposite goals, distinct codes. Bill based on what was actually done.

02Can 24935 be billed during the global period of the original amputation?

Yes, but the modifier matters. If elongation was planned as a staged follow-on to the amputation, use modifier 58. If the patient returned unexpectedly for a related complication requiring return to OR, use modifier 78. Either resets or interacts with the global period differently — modifier 58 resets the 90-day clock, modifier 78 does not.

03Does graft harvest require a separate code?

When autogenous bone graft is included in the procedure description, it is generally bundled. Check NCCI edits for any graft harvest codes you intend to report separately — modifier 59 or XS may be required if the harvest site is a distinct anatomic location not integral to the primary procedure.

04Is modifier 50 appropriate for 24935?

Bilateral upper extremity stump elongation in the same session would be unusual, but if performed, modifier 50 applies. Each payer handles bilateral payment differently; confirm whether the payer expects a single line with modifier 50 or two separate lines with LT and RT.

05What ICD-10 diagnoses support medical necessity for 24935?

Acquired absence of upper limb codes (Z89.2xx series) combined with a functional or prosthetic complication diagnosis — such as difficulty with prosthetic fitting or inadequate residual limb length — establish medical necessity. A bare absence code without documented functional deficit is often insufficient for payer review.

06Does the 90-day global period affect post-op E/M billing?

All routine post-op visits through day 90 are bundled. If you see the patient for a problem unrelated to the stump elongation during that window, append modifier 24 to the E/M code. Document clearly that the visit was for an unrelated condition.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures graft source and harvest site, fixation technique, residual limb length before and after elongation, and the functional or prosthetic indication from the surgeon's dictation. This prevents the most common audit flag for 24935: an operative note that describes a return to the amputation site without clearly distinguishing elongation from revision or re-amputation.

See how Mira captures CPT 24935 documentation