RTM for Knee Osteoarthritis: Billing Conservative Care Without Surgery

Knee osteoarthritis managed conservatively — without a replacement — is one of the cleanest fits for Remote Therapeutic Monitoring in an MSK practice. There's no surgical global period to wait out, the condition is genuinely managed over months rather than weeks, and the data that matters (pain, function, exercise adherence) is exactly what RTM is built to capture. This is the practical playbook: what to monitor, which codes apply, who's allowed to bill, and what changes if the patient eventually has surgery.

The short answer

Yes — knee osteoarthritis is billable under RTM when managed non-operatively, and it's billable from the start of the episode, because there's no procedure and therefore no 90-day global period standing in the way. The same readiness gates apply as any other RTM patient (consent, enrollment, data-days, review time, the monthly call), but nothing about the diagnosis itself delays billing the way a recent surgery would.

Why knee OA fits RTM particularly well

Not every non-operative MSK diagnosis makes an equally strong RTM case. Knee OA does, for three reasons that show up in the data pattern rather than the diagnosis code itself:

• It's managed over months, not weeks. A conservative OA plan — activity modification, a strengthening program, periodic reassessment — plays out over a long enough window that monthly device-supply and treatment-management billing is a natural fit, not a stretch.
• The outcome measures are already patient-reported. Pain and functional limitation in OA are tracked with patient-reported measures in routine practice already; RTM just moves that reporting into a cadence that also satisfies the device-supply data-day requirement.
• Adherence is the actual clinical lever. Home-exercise-program completion is one of the better predictors of whether conservative OA management holds — which means the same daily check-in that creates a billable data-day is also the thing a PT or physician actually wants visibility into.

The billing fit and the clinical fit point the same direction here — that's not true of every RTM-eligible diagnosis.

What to monitor for a knee OA patient

RTM device-supply codes require patient-transmitted data, not any specific measure — but for knee OA, three data points do most of the clinical and billing work:

• Pain (daily or near-daily). A simple 0–10 pain rating, logged consistently, is enough to count toward a data-day and gives the reviewing provider a trend line.
• Function / range-of-motion check-ins. Periodic self-reported flexion/extension or functional-limitation ratings track whether the conservative plan is working.
• Home-exercise-program completion. Whether the patient did the prescribed strengthening/mobility work that day — the single best adherence signal for a conservative OA plan, and a natural daily-checklist item.

Any one of these, logged on a given day, can count toward that day's device-supply data-day; most practices end up with all three feeding the same daily entry.

The codes, applied to knee OA

Nothing about knee OA changes the RTM code family itself — the same ladder applies as any MSK RTM episode:

The one thing that doesn't shrink for a "just OA, no surgery" patient is the interactive call requirement — 98979/98980/98981 all still need at least one documented, synchronous call with the patient that calendar month, the same as a post-op patient. Reviewing a pain trend line silently doesn't satisfy it.

Who can bill it

Conservative knee OA is typically managed by either an orthopedic physician/QHP or a physical therapist under an active plan of care — and RTM billing follows whoever is actually doing the managing:

• Physician or QHP-managed: bills RTM directly under their own NPI, no discipline modifier required.
• PT-furnished, under a plan of care: bills under the GP modifier, under general supervision (not incident-to) and the therapist's own NPI. If most of the RTM service is furnished by a PTA rather than the PT, the CQ modifier applies once assistant-furnished time crosses the de minimis standard.

Either path works — but only one biller per patient per calendar month. A surgeon and a treating PT can't both bill RTM for the same OA patient in the same month; if the referral pattern makes that ambiguous, settle ownership before the claim goes out. (See who can bill RTM and GP/CQ modifier scenarios for the full mechanics.)

Enrolling a knee OA patient, in five steps

1. Confirm the plan is non-operative. No scheduled procedure, no global period to track around.
2. Document consent and enroll. Same consent and setup requirements as any RTM patient — this is what 98975 bills.
3. Set the daily check-in to capture pain, a periodic function/ROM entry, and HEP completion.
4. Schedule the monthly interactive call up front rather than trying to fit it in at month-end — this is the requirement practices miss most often.
5. Review data-days and management time monthly before certifying, to confirm the device-supply and treatment-management thresholds were actually met.

When a total knee replacement enters the picture

Conservative management sometimes fails, and the patient proceeds to a total knee replacement (TKA). That's not a continuation of the same RTM billing — it's a transition point. Once the operating surgeon's 90-day global period for the replacement begins, that surgeon generally can't bill RTM during it; a non-operating provider, such as the treating PT delivering post-op rehab, generally can. Treat the pre-op OA data and the post-op recovery data as separate episodes rather than one continuous stretch — the billing gates (consent, enrollment, episode anchor) reset with the new episode. (See RTM and the 90-day global period for the surgeon-side mechanics.)

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