🦶 CPT 28122 — Partial Excision (Craterization, Saucerization, Sequestrectomy, or Diaphysectomy) Bone (e.g., Osteomyelitis or Bossing); Tarsal or Metatarsal Bone, Except Talus or Calcaneus
Quick Reference
wRVU: ⚠️ Verify current CMS MPFS value (see note) | Global Period: 090 (90 days) | Assistant Payable: ⚠️ Verify against MPFS assistant-at-surgery indicator | Bilateral Indicator: 1
📋 Clinical Description
CPT 28122 describes partial (not complete) excision of a tarsal or metatarsal bone, explicitly excluding the talus and calcaneus, which have their own dedicated codes. The descriptor lists four acceptable surgical techniques — craterization, saucerization, sequestrectomy, or diaphysectomy — any of which may be used to remove the diseased or abnormal portion of bone while leaving the remaining bone structure intact. Per AMA CPT Assistant guidance, this code is also the correct choice for excising a nonunion fracture fragment at the base of a metatarsal, distinguishing it from fracture repair codes, which are not appropriate when only the ununited fragment is excised without formal fracture fixation.
CPT 28122 sits within a small family of partial-excision codes distinguished purely by anatomic site: 28120 reports the identical technique performed on the talus or calcaneus, while 28124 reports it performed on a phalanx of the toe. 28122 is the only code in this trio applicable to the tarsal bones (navicular, cuboid, cuneiforms) or any metatarsal. When the entire bone — rather than a portion — is removed, 28140 (metatarsectomy) applies instead, and when an entire ray (toe plus its metatarsal) is amputated, 28810 applies rather than 28122.
The most common indication is osteomyelitis of a tarsal or metatarsal bone, frequently in the setting of a diabetic foot ulcer that has progressed to bone infection; the second most common indication is symptomatic bone bossing (an abnormal bony prominence or exostosis) causing pain or shoe-fit difficulty that has failed conservative management.
This procedure may be performed in the following clinical contexts:
- Chronic osteomyelitis with sequestrum formation — removal of a devitalized, walled-off bone fragment (sequestrum) via sequestrectomy technique, typically in a diabetic or neuropathic foot.
- Acute osteomyelitis extending from an overlying ulcer or infected wound — partial bone excision performed in conjunction with soft-tissue debridement, often as a limb-salvage alternative to more extensive resection or amputation.
- Symptomatic bone bossing/exostosis — saucerization or craterization of a prominent bony ridge on the tarsal or metatarsal, most often addressed electively after failed shoe modification or padding.
- Nonunion fracture fragment excision — per AMA CPT Assistant, excision of an ununited avulsion fracture fragment (e.g., at the base of the fifth metatarsal) without formal fracture fixation is reported with 28122 rather than a fracture repair code.
- Diaphysectomy for diaphyseal bone infection or bossing — removal of a segment of the bone shaft rather than the metaphyseal/epiphyseal end, used when the disease process is localized to the mid-shaft region.
🔬 Anatomical & Procedural Considerations
| Technique | Mechanism | Key Notes |
|---|---|---|
| Sequestrectomy | Surgical removal of a sequestrum — a segment of dead bone that has separated from viable bone in chronic osteomyelitis | Requires the operative note to describe the sequestrum specifically; pathology confirmation of nonviable bone strongly supports the code on audit |
| Saucerization/Craterization | Shaving or scooping out a shallow crater in the bone surface to remove infected or bossed cortical bone while leaving the underlying medullary bone intact | Most common technique for symptomatic exostosis/bossing; documentation should specify the depth and extent of bone removed |
| Diaphysectomy | Excision of a segment of the diaphysis (shaft) of the bone | Used when disease is localized to the shaft rather than the metaphysis; distinguish clearly from complete bone removal, which would instead be reported with 28140 |
Clinical Pearl
Coders should confirm the operative note names the specific bone(s) excised by anatomic name and confirms they are tarsal or metatarsal — not talus, calcaneus, or phalanx — since those sites route to different codes (28120, 28124) despite an identical technique descriptor. Documentation that only states “partial bone excision” without naming the specific bone and technique is a frequent audit failure point.
✅ Procedure Includes
- Surgical incision and exposure of the affected tarsal or metatarsal bone.
- Partial excision of the diseased, infected, necrotic, or bossed portion of bone via craterization, saucerization, sequestrectomy, or diaphysectomy technique.
- Intraoperative assessment of remaining bone viability and adequacy of margins.
- Irrigation of the surgical site and, where clinically indicated, local antibiotic bead placement (though antibiotic bead delivery itself, CPT 20700-20705, may be separately reportable when performed).
- Wound closure and application of postoperative dressing/immobilization.
- Documentation of the specific bone excised, technique used, and extent of resection.
❌ Excludes / Do Not Report Together
| Code | Description | Relationship to 28122 |
|---|---|---|
| 28120 | Partial excision (craterization, saucerization, sequestrectomy, or diaphysectomy) bone; talus or calcaneus | Site-exclusive alternative — used for the identical technique performed on the talus or calcaneus rather than a tarsal or metatarsal bone; never both for the same bone |
| 28124 | Partial excision (craterization, saucerization, sequestrectomy, or diaphysectomy) bone; phalanx of toe | Site-exclusive alternative for toe phalanges; not reported together with 28122 for the same bone |
| 28140 | Metatarsectomy | More extensive procedure — complete removal of a metatarsal bone; when the entire bone (not just a portion) is excised, 28140 supersedes 28122 |
| 28810 | Amputation, metatarsal, with toe, single (ray resection) | More extensive procedure encompassing both bone and digit; when a full ray resection is performed, 28810 is reported instead of, not in addition to, 28122 |
| 28005 | Incision and drainage, bone abscess, foot | NCCI-bundled with 28122 when performed at the same session/site as an integral part of gaining surgical access; separately reportable only with modifier -59/-XS and clear documentation of a distinct incision/drainage site |
| E/M codes (992xx / 990xx) | Office/inpatient visit, any level | Separately reportable only when modifier -25 is appended to the E/M code, documenting a significant, separately identifiable evaluation beyond the routine pre-procedure assessment |
Bundling Alert — Global Period is 090, Not 000 or 010
CPT 28122 carries a full 90-day major-surgery global period, bundling the day before surgery, the day of surgery, and 90 days of related postoperative care. Unrelated E/M visits during this window require modifier -24 with clear documentation that the visit addressed a condition unrelated to the excision. A common audit finding is billing routine post-op wound checks or dressing changes separately within the 90-day window — these are bundled and not separately payable absent a genuinely unrelated complaint.
🌳 Code Tree — Surgery: Musculoskeletal System (Excision Procedures on the Foot and Toes)
CPT 28100-28175 Surgery: Musculoskeletal System — Excision Procedures on the Foot and Toes
│
├── 28100-28118 Excision/Curettage of Bone Cyst or Tumor; Ostectomy
│ ├── 28104 Excision or curettage of bone cyst or tumor, tarsal or metatarsal
│ └── 28118 Ostectomy, calcaneus
│
├── 28120-28126 Partial Excision (Craterization, Saucerization, Sequestrectomy, or Diaphysectomy)
│ ├── 28120 Partial excision; talus or calcaneus (Global: 090)
│ ├── ▶▶ 28122 ◀◀ Partial excision; tarsal or metatarsal bone, except talus or calcaneus ← YOU ARE HERE (Global: 090)
│ ├── 28124 Partial excision; phalanx of toe (Global: 090)
│ └── 28126 Resection, partial or complete, phalangeal base, each toe (Global: 090)
│
├── 28130 Talectomy (astragalectomy)
│
└── 28140-28160 Complete Bone Excision Procedures
├── 28140 Metatarsectomy
└── 28150 Phalangectomy, toe, each toe💰 RVU & Reimbursement Profile
| Component | Value |
|---|---|
| Work RVU (wRVU) | ⚠️ Not independently confirmed — one 2026 third-party fee reference cited 17.94 total RVUs (not the work component alone); the work RVU value must be pulled separately from the current CMS MPFS Addendum B before this note is finalized for billing use |
| Global Period | 090 (90 days) |
| Bilateral Indicator | 1 — standard bilateral payment rules apply: 150% payment adjustment when performed bilaterally in the same session (100% first side, 50% second side) |
| Assistant Surgeon | ⚠️ Verify current MPFS assistant-at-surgery indicator — not confidently known for this code |
| Co-Surgeon | ❌ Not typically applicable |
| Team Surgery | ❌ Not typically applicable |
| PC/TC Split | ❌ No — procedure code only (Indicator 0) |
| Modifier -51 Exempt | No |
| Anesthesia | General or regional (ankle block/spinal) anesthesia typically used; separately billable under the 00XXX anesthesia series when performed by a separate anesthesia provider |
Bilateral Billing Rules
CPT 28122 has a bilateral indicator of 1, meaning standard Medicare bilateral payment rules apply. When the identical procedure is performed on corresponding tarsal or metatarsal bones of both feet in the same session, report on a single line with modifier -50, or per specific MAC preference, on two lines with -RT and -LT. Medicare’s 150% bilateral rule applies: 100% payment for the higher-valued side, 50% for the second side.
🏷️ Modifier Reference
| Modifier | Name | When to Apply |
|---|---|---|
| -RT | Right Side | Procedure performed on a right tarsal or metatarsal bone |
| -LT | Left Side | Procedure performed on a left tarsal or metatarsal bone |
| -50 | Bilateral Procedure | Identical procedure performed on corresponding bones of both feet in the same session; confirm MAC preference for single-line -50 vs. two-line -RT/-LT billing format |
| -22 | Increased Procedural Services | Applied when the excision is significantly more extensive or complex than typical (e.g., multiple bones, extensive sequestrum, or unusually difficult exposure); requires a comparative operative note statement documenting the added complexity |
| -24 | Unrelated E/M During Postoperative Period | Applied to the E/M code when a patient returns within the 90-day global window for a condition unrelated to the bone excision; document the unrelated nature explicitly |
| -25 | Significant, Separately Identifiable E/M | Applied to the E/M code — not 28122 — when an office visit is performed on the same date; documentation must support a separate, medically necessary evaluation beyond the pre-procedure assessment |
| -51 | Multiple Procedures | When 28122 is performed alongside other surgical procedures at the same session; applied to the lower-valued code |
| -58 | Staged or Related Procedure | Applied when a planned staged procedure (e.g., delayed closure or bone grafting) occurs during the 90-day global period |
| -59 | Distinct Procedural Service | When payers inappropriately bundle 28122 with another procedure (e.g., incision and drainage) at a distinct site; documents the anatomically separate location |
| -78 | Unplanned Return to OR | Applied when an unplanned return to the OR occurs during the global period for a related complication (e.g., recurrent infection requiring further debridement) |
| -79 | Unrelated Procedure During Postoperative Period | Applied when an unrelated procedure is performed on the same patient during the 90-day global window |
🩺 Common ICD-10-CM Pairings
Osteomyelitis of Tarsal/Metatarsal Bone
| ICD-10 Code | Description | HCC? | Clinical Notes |
|---|---|---|---|
| M86.171 | Other acute osteomyelitis, right ankle and foot | ❌ No | Most specific right-sided code supporting acute infectious indication for partial bone excision |
| M86.172 | Other acute osteomyelitis, left ankle and foot | ❌ No | Left-sided equivalent |
| M86.671 | Other chronic osteomyelitis, right ankle and foot | ❌ No | Use when the infection is documented as chronic, typically supporting sequestrectomy technique specifically |
| M86.672 | Other chronic osteomyelitis, left ankle and foot | ❌ No | Left-sided equivalent |
Nonunion Fracture Fragment
| ICD-10 Code | Description | HCC? | Clinical Notes |
|---|---|---|---|
| M84.171 | Nonunion of fracture, right ankle and foot | ❌ No | Supports 28122 per AMA CPT Assistant guidance when the procedure excises an ununited avulsion fracture fragment without formal fracture fixation |
Underlying Etiology / Complication Codes
| ICD-10 Code | Description | HCC? | Clinical Notes |
|---|---|---|---|
| E11.621 | Type 2 diabetes mellitus with foot ulcer | ✅ HCC 38 (Diabetes with Chronic Complications) | Report as an additional diagnosis whenever osteomyelitis originates from a diabetic foot ulcer; this pairing is often required by payers to establish medical necessity and supports the risk-adjustment/HCC capture for the encounter |
Coding Specificity Reminder
The most commonly missed specificity element on this code’s diagnosis pairings is laterality on the M86 osteomyelitis series, followed by acute vs. chronic classification — the operative and clinical documentation should clearly support which applies, since chronic osteomyelitis with sequestrum most directly supports the sequestrectomy technique named in the CPT descriptor. Never default to an unspecified-laterality M86.9x code when the operative note clearly documents a specific side; query the provider rather than downcoding specificity to match an incomplete note.
🏥 MS-DRG Considerations (Inpatient)
Inpatient Coding Reminder
CPT 28122 is commonly performed in the inpatient setting for diabetic or neuropathic foot osteomyelitis requiring limb salvage. The corresponding ICD-10-PCS excision code (root operation Excision, no diagnostic qualifier) groups to MDC 08 (Musculoskeletal System & Connective Tissue), most typically within the “Other Musculoskeletal System O.R. Procedures” DRG family (570-572, with MCC / with CC / without CC-MCC); confirm the exact DRG bucket against the current MS-DRG v43.0 GROUPER logic, as CMS periodically reclassifies specific foot-procedure code sets. The principal diagnosis — typically the specific M86 osteomyelitis code — combined with any documented CC/MCC (e.g., uncontrolled diabetes, sepsis, or peripheral vascular disease) is the primary DRG-weight driver on these admissions.
🔧 ICD-10-PCS Equivalents (Inpatient Facility Coding)
Note
Inpatient PCS coding for this procedure is common in diabetic limb-salvage admissions. The root operation is Excision (B) — cutting out/off, without replacement, a portion of a body part — matching the CPT descriptor’s “partial excision” language precisely. Approach is virtually always Open (0), since this procedure requires a surgical incision to expose and access the bone (unlike wound-bed debridement, which may use an External approach). If only a bone biopsy/diagnostic sample is taken rather than a therapeutic excision, the diagnostic qualifier X applies instead of Z in the seventh character position.
| PCS Code | Full Description | Applicable Modality |
|---|---|---|
0QBL0ZZ | Excision of Right Tarsal, Open Approach, No Device, No Qualifier | Partial excision of right tarsal bone (navicular, cuboid, or cuneiform) |
0QBM0ZZ | Excision of Left Tarsal, Open Approach, No Device, No Qualifier | Partial excision of left tarsal bone |
0QBN0ZZ | Excision of Right Metatarsal, Open Approach, No Device, No Qualifier | Partial excision of right metatarsal bone |
0QBP0ZZ | Excision of Left Metatarsal, Open Approach, No Device, No Qualifier | Partial excision of left metatarsal bone |
PCS Character Analysis — 0QBN0ZZ
| Position | Character | Value | Definition |
|---|---|---|---|
| 1 | Section | 0 | Medical and Surgical |
| 2 | Body System | Q | Lower Bones |
| 3 | Root Operation | B | Excision (cutting out/off, without replacement, a portion of a body part) |
| 4 | Body Part | N | Metatarsal, Right |
| 5 | Approach | 0 | Open — surgical incision made to expose the site of the procedure |
| 6 | Device | Z | No Device |
| 7 | Qualifier | Z | No Qualifier (use X — Diagnostic — instead if the excision is a biopsy rather than therapeutic) |
PCS Root Operation: Excision vs. Resection
- Use Excision (B) for the standard [[28122]] scenario — a portion of the bone is removed, which matches the CPT descriptor’s “partial excision” language.
- Use Resection (T) only if the entire bone is removed, which corresponds instead to 28140 (metatarsectomy) at the CPT level, not 28122.
- When bilateral or multi-bone excision is performed, assign a separate PCS code line for each distinct body part treated — PCS has no bilateral modifier equivalent.
📝 Coding Examples
Example 1 — Inpatient: Diabetic Foot Osteomyelitis, Sequestrectomy
Clinical Scenario: A 61-year-old male with type 2 diabetes and a chronic plantar forefoot ulcer is admitted with imaging-confirmed chronic osteomyelitis of the right third metatarsal, with a visible sequestrum on pre-op imaging. The surgeon performs sequestrectomy, removing the devitalized bone segment down to viable, bleeding bone margins. No separately identifiable E/M is documented beyond the routine pre-procedure assessment.
| Field | Code | Rationale |
|---|---|---|
| CPT | 28122-RT | Partial excision of right metatarsal bone via sequestrectomy technique for chronic osteomyelitis |
| PDx | M86.671 | Other chronic osteomyelitis, right ankle and foot — most specific code supporting the sequestrectomy technique performed |
| SDx | E11.621 | Type 2 diabetes mellitus with foot ulcer — establishes underlying etiology and supports medical necessity |
Note
No modifier -25 is billed here since no separately identifiable E/M was documented; the pre-procedure assessment is bundled into the 90-day global period.
Example 2 — ASC: Bilateral Bone Bossing, Saucerization
Clinical Scenario: A 45-year-old female presents with symptomatic bony prominences on the dorsal aspect of the second metatarsal bones bilaterally, causing chronic shoe-fit pain unresponsive to padding and shoe modification. The surgeon performs saucerization of both metatarsal bones in the same operative session. An unrelated same-day E/M visit is documented for evaluation of a separate plantar wart, supporting a -25 modifier.
| Field | Code | Rationale |
|---|---|---|
| CPT 1 | 99213-25 | Significant, separately identifiable E/M for the unrelated plantar wart evaluation |
| CPT 2 | 28122-50 | Bilateral partial excision (saucerization) of the second metatarsal bones, reported on a single line with modifier -50 per bilateral billing convention |
| PDx | M89.9 | Disorder of bone, unspecified — placeholder pending confirmation of the most specific exostosis/bossing code available; query provider for greater specificity before finalizing |
Warning
Confirm the most specific ICD-10-CM code for symptomatic bone bossing/exostosis before finalizing this example — the placeholder code shown is not adequately specific and should not be used in an actual claim without provider query and code verification.
Example 3 — Inpatient: Return to OR for Recurrent Infection
Clinical Scenario: A 70-year-old male underwent 28122 for left first metatarsal osteomyelitis 3 weeks prior. He now returns with recurrent purulent drainage and imaging evidence of residual infected bone. The surgeon returns him to the OR for repeat partial excision and further sequestrectomy of the same bone.
| Field | Code | Rationale |
|---|---|---|
| CPT | 28122-LT-78 | Unplanned return to the OR during the 90-day global period for a related complication (recurrent osteomyelitis at the same surgical site) |
| PDx | M86.672 | Other chronic osteomyelitis, left ankle and foot — recurrent/residual infection at the prior surgical site |
Global period reminder
Modifier -78 documents that this return to the OR is related to the original procedure and occurred within the 90-day global window; it triggers a reduced intraoperative-only payment rather than a full new global package, since the pre- and post-operative components of the original procedure are not being repeated.
⚠️ Common Coding Pitfalls
-
Confusing partial with complete bone excision: 28122 applies only when a portion of the tarsal or metatarsal bone is removed. If the operative note documents removal of the entire bone, the correct code is 28140 (metatarsectomy), not 28122 — this is a frequent up/downcoding error depending on which direction the mistake runs.
-
Selecting 28122 for talus, calcaneus, or phalanx sites: The descriptor explicitly excludes the talus and calcaneus (routed to 28120) and does not include toe phalanges (routed to 28124). Coders must confirm the specific bone named in the operative note before finalizing code selection.
-
Missing named-bone and technique documentation: Documentation that only states “partial bone excision” without naming the specific bone and the technique used (craterization, saucerization, sequestrectomy, or diaphysectomy) is a common audit failure; the operative note must name both to defend code selection.
-
Reporting 28005 (I&D) in addition to 28122 without a distinct site: NCCI bundles incision and drainage into 28122 when it is an integral part of surgical access to the bone. Separately reporting 28005 requires clear documentation of a truly distinct incision/drainage site and appropriate use of modifier -59/-XS.
-
Billing routine post-op visits separately within the 90-day global: Unlike shorter-global debridement codes, 28122 carries a full 90-day global period. Routine wound checks, dressing changes, or suture removal within that window are bundled and not separately payable absent a genuinely unrelated complaint supported by modifier -24.
-
Defaulting to unspecified osteomyelitis or bossing codes without querying: Both laterality and acute/chronic classification are frequently under-specified on M86 osteomyelitis codes, and no well-established single ICD-10-CM code cleanly captures symptomatic “bossing” without provider query — coders should query rather than default to a vague placeholder code.
📎 Sources
AMA CPT 2026 Professional Edition · AMA CPT Assistant, August 2020 — “Reporting Excision of Nonunion Fracture Fragment” · CMS CY2026 Medicare Physician Fee Schedule Final Rule (CMS-1832-F) · CMS RVU26 Relative Value Files (confirm work RVU against Addendum B) · ICD-10-CM Official Guidelines for Coding and Reporting FY2026 · ICD-10-PCS Official Guidelines for Coding and Reporting FY2026 · CMS ICD-10-CM/PCS MS-DRG v43.0 Definitions Manual, MDC 08 · AAPC Codify — CPT 28122 Coding Reference · NCCI Policy Manual, Musculoskeletal System Chapter, CMS 2025-2026
wRVU and assistant-surgeon indicator values are flagged above for confirmation against the live CMS MPFS Addendum B, as exact CY2026 work-RVU-specific figures were not independently verifiable at time of writing. The ICD-10-CM code for symptomatic bone bossing/exostosis in Example 2 is a placeholder pending further specificity research and should not be used without provider query and verification.
Sources listed above correspond to superscript citations throughout this note. Verify all Medicare payment figures against your current CMS PFS Lookup tool and applicable MAC LCD prior to claim submission. Please use the latest AAPC/AHIMA Coding Books to verify each code within this note.