
InkWell Health, a medtech innovator founded by orthopedic sales veteran John Matthews, has officially launched its first product, a post-surgery "smart tattoo" designed to revolutionize recovery monitoring for knee replacement and knee injury patients. The company's mission is simple yet transformative: to give surgeons, physical therapists, and patients real-time, medical-grade insights into recovery progress between hospital discharge and follow-up appointments.
Applied directly to the skin after surgery, the InkWell Health temporary tattoo is designed to function as a monitoring tool that tracks swelling, temperature, and range of motion, three of the critical indicators of post-surgical success. "For most patients, the period after surgery can feel like a black box," says CEO John Matthews. "Surgeons may not see them for weeks, and that's when complications can arise. We aim to create a way for both patients and clinicians to know exactly how healing is progressing safely."
The tattoo, applied to the inner leg immediately after surgery, is paired with the InkWell Health app. Acting as what Matthews describes as a "human QR code," the tattoo allows patients to scan it with their smartphone, automatically uploading real-time data to their personal app. Clinicians can then access that same information through a secure portal, enabling proactive care and intervention if recovery metrics deviate from normal ranges.

"The data we deliver is not just convenient, it's medical-grade," Matthews says. "Our product is designed to give clinicians actionable data that can prevent infections, reduce swelling-related ER visits, and help avoid manipulations, which are the last thing any patient wants."
Each tattoo lasts about two weeks, and patients are sent home with two to three backups to replace them as they heal. To support users, InkWell Health's "Care Navigators" stay in contact with patients, offering guidance on reapplying tattoos, troubleshooting the app, and flagging any concerns that may arise.
Beyond its technological promise, the product is also designed with healthcare efficiency in mind. InkWell Health operates as a business-to-business provider, selling directly to orthopedic and physical therapy clinics. Existing reimbursement codes in the U.S. make it easier for clinicians to implement the system without financial barriers, a key advantage that Matthews and his team actively help clinics navigate. "We don't just supply the product," he explains. "We educate providers on how to integrate it effectively and how to use the reimbursement pathways that already exist. That support is part of what makes our model work."
The company's first clinical series, conducted across three sites in Michigan, delivered encouraging results. The app is designed to be intuitive and user-friendly.
Since its soft launch at the American Association of Hip and Knee Surgeons (AAHKS) meeting in late 2024, InkWell Health has expanded to multiple clinics across seven U.S. states, with plans for continued growth in the months ahead. Matthews, who conceived the idea in 2022 and officially launched the company that December, says this is only the beginning.
"We are proving that real-time, skin-level data can change recovery outcomes," Matthews notes. "Knee surgery is just the start. Our team is already testing similar technology for foot and ankle, hip, and shoulder procedures. The vision is to give every orthopedic patient and their clinician the data needed to heal with confidence."
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