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The Next Generation of Articular Cartilage Repair

ABOUT | Moirai Orthopaedics
Moirai Orthopaedics has developed an advanced, minimally-invasive surgical Pyrocarbon Implant Replacement (PIR) System for the treatment of degenerative and arthritic knee disorders.

The PIR is specifically intended to treat symptomatic cartilage defects of the anterior or central medial femoral condyle and the patellofemoral joint. The pyrocarbon articular resurfacing implant is a single component that consists of an anatomic articular surface cap with bone-contacting surfaces coated with hydroxylapatite (HA) for fixation.

The PIR implant in bone


Osteochondral and chondral defects occur frequently – not only in young athletes, but also in older and more sedentary individuals. Articular cartilage defects of the knee are common, painful, and predispose patients to debilitating osteoarthritis. Making matters worse, avascular cartilage tissue has an extremely low capacity for repair.

The current treatment options, including regenerative and replacement treatments, are suitable for only a range of individuals. Active, middle-aged patients are left to opt for procedures that may not be suitable for their defects, often leading to poor outcomes.

Market Overview

PRODUCT | Benefits
The PIR is designed to restore the articular surface of a chondral or osteochondral lesion of the medial femoral condyle (MFC) or patellofemoral joint (PFG) in order to relieve pain and restore function, while preserving as much host bone and intact cartilage as possible.

The implantation procedure can be performed in an out-patient setting and utilizes a complete instrument kit, which includes alignment guides, cutters, and trials to ensure optimal implant size, orientation, and placement.


Why the PIR is the superior choice for surgeons and patients.

An image of a stethoscope

The PIR offers a significantly better, minimally-invasive alternative to current regenerative solutions to treat articular cartilage defects of the medial femoral condyle and patellofemoral groove in the knee.

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Why patients should choose the PIR over alternative surgical options.

An image of a bandaid

The PIR results in a shorter operative and rehabilitation time for most patients. The PIR preserves as much host bone and intact cartilage as possible while relieving pain and without compromising future reconstructive options.

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Why the PIR will compete in a lucrative niche in the treatment of cartilage defects.

An image of a laboratory beaker

The PIR targets a $2 billion market in the treatment of articular cartilage defects by addressing a large, underserved market of 35- to 65-year-olds that is not well suited for regenerative therapies or total knee replacement.

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CBS News: "Are Doctors Performing Too Many Unnecessary Knee-Replacement Surgeries?"
In 2014, CBS News profiled a study that was published in the journal Arthritis & Rheumatology. The study followed 175 patients who underwent total knee replacement surgery and found that only 44% of those surgeries were “appropriate,” meaning the expected benefits outweighed the likely risks for that patient.

“In 34 percent of cases evaluated, the surgery was deemed to be inappropriate, with expected risks outweighing the benefits. The rest of the cases, 22 percent, were considered inconclusive, with risks and benefits approximately equal.”

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PIR Knee System Receives FDA Approval to Initiate Clinical Study
Moirai Orthopaedics, LLC, is pleased to announce it has received approval from the U.S. Food and Drug Administration (FDA) for its Investigational Device Exemption (IDE) application to initiate clinical study of the company’s multi-patented Pyrocarbon Implant Replacement (PIR) System. The PIR System was developed in conjunction with the Fellowship of Orthopaedic Researchers.

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The Pyrocarbon Implant Replacement (PIR) System