Podiatry RTM: Diabetic Foot and Wound Monitoring

Why Diabetic Foot Patients Are the Perfect RTM Population

Diabetic foot disease represents the highest-acuity outpatient population in podiatry, and it maps precisely onto the clinical rationale for remote therapeutic monitoring (RTM). Patients with peripheral arterial disease (PAD), peripheral neuropathy, and diabetes mellitus (Type 1 or Type 2) require ongoing surveillance between visits because wound status can deteriorate rapidly — a Wagner Grade 1 superficial ulcer can progress to a Grade 3 deep abscess within days without adequate monitoring. RTM is designed for this exact scenario: continuous data collection outside the four walls of the clinic using patient-reported outcomes and digital photo submission.

For podiatry, the qualifying condition does not need to be musculoskeletal in the traditional orthopedic sense. CMS has clarified that RTM applies to conditions involving musculoskeletal and/or respiratory systems, and diabetic foot wounds — which involve bone, soft tissue, vascular perfusion, and sensory nerve function — qualify under musculoskeletal therapeutic monitoring. Practices that enroll diabetic foot patients in RTM programs capture billable data on wound measurements, periwound skin integrity, exudate characteristics, and pain levels that are otherwise invisible between appointments.

The clinical risk profile is compelling: approximately 34 million Americans have diabetes, and roughly 15–25% will develop a diabetic foot ulcer during their lifetime. Within your active podiatry panel, the diabetic wound subgroup likely represents 20–35% of total patient volume. Activating RTM for even half of that cohort creates a systematic revenue stream that does not require additional clinic slots. Each enrolled patient can generate $130–$165 in additional monthly revenue through properly documented RTM codes — revenue that reflects genuine clinical oversight, not administrative upcoding.

RTM CPT Code Structure: 98975, 98977, 98980, and 98981

Understanding the RTM billing architecture is essential before enrolling your first patient. The four codes that apply to podiatry wound monitoring form a logical progression from device setup through ongoing management.

CPT 98975 (one-time per episode) covers the initial setup and patient education for the RTM device or app. For podiatry, this means onboarding the patient to your photo-submission platform, explaining the wound measurement protocol, and documenting that informed consent was obtained. Bill 98975 once per new enrollment event — not per calendar month. Typical reimbursement: $19–$22 under most commercial schedules; approximately $18.73 under 2024 Medicare Physician Fee Schedule (MPFS).

CPT 98977 is the monthly supply code for musculoskeletal monitoring devices/software. It requires that a medical device (including FDA-registered software applications) is used to collect data. Bill once per 30-day period. Medicare allowable: approximately $53.98. Commercial rates vary from $45–$75 depending on payer.

CPT 98980 covers the first 20 minutes of RTM treatment management services in a calendar month — physician or qualified non-physician practitioner (NPP) review of data, clinical decision-making, and documented communication with the patient or caregiver. This is the core billable activity. Medicare allowable: approximately $50.18. Requires at least one interactive communication (phone, video, or portal message) with the patient during the month.

CPT 98981 is the add-on for each additional 20 minutes beyond the first 20 in the same calendar month. For complex wound patients requiring frequent check-ins, 98981 can be billed multiple times. Medicare allowable: approximately $40.84 per additional 20-minute block.

Total per-patient revenue for a standard month (98977 + 98980): approximately $104.16 under Medicare — and significantly more under commercial payers. For a practice managing 60 enrolled diabetic foot patients, that equates to roughly $6,250 monthly from Medicare alone, before accounting for the subset of patients generating 98981 add-on codes.

Wagner Grade Progression Tracking via RTM

The Wagner Grading System (Grades 0–5) is the most widely used classification for diabetic foot ulcers in clinical documentation and prior authorization. RTM allows your team to track Wagner grade changes in near-real-time through systematic photo submission, rather than waiting for the next office visit to identify deterioration.

In a properly structured RTM protocol, patients with active Wagner Grade 1 or Grade 2 wounds submit wound photographs every 72 hours using a standardized overhead template — heel of hand visible for scale, consistent lighting, no flash glare obscuring wound bed color. Your clinical team reviews each submission on the same business day. This cadence allows early identification of perilesional erythema suggesting cellulitis, fibrin slough accumulation indicating inadequate debridement frequency, or wound margin undermining that may require escalation to MRI (CPT 73718–73723) to rule out osteomyelitis.

For Wagner Grade 0 patients (at-risk skin, no open wound), RTM can capture foot skin integrity photos, pressure point callus formation, and nail plate changes. This population is often overlooked for monitoring despite representing the highest opportunity for prevention. Documenting weekly check-ins for high-risk Grade 0 patients — those with ABI below 0.9, HbA1c above 8.0%, or a prior ulcer history — supports both medical necessity for RTM enrollment and, downstream, prior authorization for preventive DME such as custom diabetic footwear.

In your RTM platform, each patient's Wagner grade should be recorded at enrollment as the baseline and updated with each clinical review of submitted photos. A 60-day RTM record showing progression from Grade 1 to Grade 2 with documented daily wound measurements, wound care instructions provided, and timely physician response creates a powerful clinical narrative — one that supports both the medical record and any payer audit of wound care billing under CPT 97597 (debridement, selective), 97598 (additional 20 cm²), or 11042–11047 (debridement by depth).

Charcot Joint Monitoring and Peripheral Neuropathy Symptom Tracking

Charcot neuroarthropathy (Charcot foot) is among the most serious complications of peripheral neuropathy. It involves progressive destruction of the foot and ankle bones and joints due to repetitive microtrauma in an insensate extremity. The acute phase — marked by unilateral erythema, warmth, and edema without open ulceration — is frequently misdiagnosed as cellulitis or DVT, delaying offloading treatment and allowing destructive joint collapse to proceed.

RTM is particularly well-suited to Charcot monitoring because temperature asymmetry — a greater than 2°F difference between the affected foot and the contralateral foot — is the most reliable indicator of acute Charcot activity. Patients with total contact casts (TCC) or removable cast walkers can submit daily temperature readings using inexpensive infrared skin thermometers. Your clinical team reviews these submissions and adjusts offloading protocols based on temperature trend data, reducing unnecessary office visits while maintaining vigilant oversight.

For peripheral neuropathy symptom tracking, RTM enables patients to log daily paresthesia severity scores (0–10 numeric rating scale), burning sensation patterns, and any new sensory changes on a validated tool such as the MNSI (Michigan Neuropathy Screening Instrument). This longitudinal patient-reported outcome data is valuable beyond RTM billing — it provides objective documentation of symptom progression that supports prior authorization for duloxetine (SNRIs), gabapentin (CPT billing under neurology consult), pregabalin, or topical compounded formulations prescribed by your practice.

For Charcot patients, document clearly in RTM records: the phase of Charcot (acute vs. quiescent), the Eichenholtz stage (I–III), current offloading modality, and the temperature differential trend. When temperature asymmetry normalizes below 2°F for three consecutive weeks, that data supports transitioning from TCC to custom-molded orthotic — which itself may trigger a new prior authorization workflow for HCPCS L-code DME.

Pedal Pulse Assessment and Vascular Monitoring Integration

Peripheral arterial disease (PAD) is present in 20–30% of patients with diabetic foot ulcers and is the primary driver of non-healing wounds. While RTM does not replace an ankle-brachial index (ABI) study (CPT 93922) or a vascular surgery referral, it does provide a framework for systematic vascular status check-ins between clinic visits.

Trained patients or caregivers can be taught basic pedal pulse assessment — specifically, whether the dorsalis pedis and posterior tibial pulses are palpable or absent. While this is not equivalent to Doppler assessment, absence of previously palpable pulses is a red flag that your clinical team can triage immediately through RTM review. A patient who reports loss of palpable pulse combined with increased wound pain and new pale or dusky wound bed coloration submitted via photo warrants same-day triage — either an urgent office visit or direct referral to vascular surgery.

RTM records should document the vascular baseline established at enrollment: ABI values if recently obtained, toe pressures (TcPO₂) if available, and which pulses were palpable at the last office visit. Monthly RTM management notes under CPT 98980 should reference any reported vascular changes and the clinical response — a telephone call advising the patient to seek urgent evaluation is billable RTM interaction that is also defensible documentation in the event of a wound-related adverse outcome.

For practices that co-manage diabetic foot patients with vascular surgery or interventional radiology, RTM data creates a shared clinical record that demonstrates active monitoring and timely response — reducing liability risk and supporting the medical necessity argument for revascularization procedures (CPT 37228–37235 for lower extremity endovascular) when payers request documentation of pre-procedure wound status.

Revenue Math: 60 Diabetic Patients on RTM

Let us build the full revenue projection for a podiatry practice enrolling 60 diabetic foot patients in RTM. These calculations use 2024 Medicare MPFS allowables as the floor, with commercial payers typically reimbursing 15–35% above Medicare rates.

Total Monthly Recurring Revenue: $3,238.80 + $3,010.80 + $735.12 = $6,984.72/month

Annualized RTM Revenue (after Month 1): $6,984.72 × 12 = $83,816.64/year

To achieve these numbers, the practice must maintain compliant documentation: a minimum of 16 days of data collection per 30-day period for 98977, a minimum of 20 minutes of clinical review time documented for 98980, and at least one synchronous or asynchronous patient interaction per month. A clinical coordinator spending 3 hours per day on RTM data review can comfortably manage 60–80 patients, particularly when the review workflow is integrated into a purpose-built RTM platform.

Commercial payer revenue will exceed Medicare rates. A practice with a payer mix of 40% Medicare, 35% commercial, and 25% Medicaid/other might see blended per-patient monthly revenue of $115–$140, pushing the 60-patient program to $8,000–$8,400/month in RTM revenue alone — before any downstream revenue from wound care visits, DME, or surgical procedures that are better documented and better supported by the continuous RTM record.

RTM Program Setup: Enrollment Criteria and Patient Onboarding

A successful RTM program begins with clear enrollment criteria that your front desk and clinical staff can apply consistently. For podiatry, appropriate RTM candidates include: patients with an active diabetic foot ulcer (any Wagner grade), patients with a Charcot foot diagnosis (ICD-10: M14.67x) in the acute or monitoring phase, patients with peripheral neuropathy (E11.40–E11.49) and a history of prior ulceration, and high-risk diabetic patients (HbA1c > 8.0%, ABI < 0.9, loss of protective sensation on 10-g monofilament) who have not yet developed an ulcer but are being monitored preventively.

Exclusion criteria should be clearly documented: patients without a smartphone or caregiver with smartphone access, patients with significant cognitive impairment that prevents reliable self-reporting, and patients whose wounds require daily in-office wound care (these patients will generate sufficient E&M and procedure revenue without RTM and may not meet the "remote" requirement).

The onboarding visit (CPT 98975) should include a structured 15-minute education session: how to photograph wounds using the standardized protocol, how to submit photos through the patient portal, how to record daily temperature readings, how to log pain and symptom scores, and who to call if they experience acute changes. This education session can be conducted by your medical assistant or LPN under physician supervision and should be documented in the patient's chart with the RTM consent form and the device/app setup confirmation.

Most commercial RTM platforms provide a patient-facing mobile app with guided photo capture (overlay grid, lighting prompts, scale reference) that dramatically improves photo quality and reduces the clinical staff burden of interpreting poor-quality images. When evaluating RTM platforms, prioritize those with EHR integration that auto-populates RTM time logs into billable encounter notes — manual time logging is the most common compliance failure in RTM programs.

Documentation and Compliance Requirements for Podiatry RTM

RTM documentation must satisfy CMS requirements to survive audit. Each calendar month of RTM billing requires a distinct set of documentation elements that your EHR or RTM platform must capture systematically.

For CPT 98977 (monthly supply), the record must show: the device or software used, confirmation that the patient used the device during the billing month, and the number of days data was transmitted (minimum 16 days per 30-day period). Your RTM platform should generate a monthly data transmission report that can be attached to the billing encounter.

For CPT 98980 (first 20 minutes of management), the record must show: the date(s) and duration of each clinical review session, what data was reviewed (wound photos, temperature logs, symptom scores), the clinical assessment and plan documented for each review, and documentation of at least one real-time interactive communication with the patient or caregiver during the month. This interaction can be a telephone call, a video visit, or a two-way asynchronous portal message — CMS clarified in the 2024 MPFS Final Rule that portal messaging qualifies.

For CPT 98981 (additional 20 minutes), document the additional time separately with start/stop times. Time cannot be counted across multiple practitioners to reach a single billing threshold — one supervising physician or NPP must accumulate the time.

Fraud risk areas to address: (1) billing 98977 without confirming patient actually transmitted data (check your platform's transmission logs before billing); (2) counting time spent on wound debridement procedures toward RTM management time (procedure time is excluded); (3) billing RTM in months where the patient had zero portal interactions (no-interaction months should be flagged and escalated to a phone call before month-end). A quarterly internal audit of 10% of RTM records is a reasonable compliance safeguard for any practice billing over $50,000 annually in RTM codes.