Were You Told You Need a Knee Replacement for Your Kneecap?
There Is Another Option.
Patients with arthritis or cartilage damage of the patellofemoral joint — the kneecap and its groove — are routinely told they need a metal and plastic joint replacement. For a 25-year-old athlete who has dislocated their kneecap repeatedly, or a 45-year-old who wants to stay active for decades, that recommendation is devastating. A traditional replacement means permanent activity restrictions, a finite implant lifespan, and the near-certainty of revision surgery down the road.
Dr. Raffy Mirzayan invented a different solution.
BioPFJ™ is a complete biological reconstruction of the patellofemoral joint using fresh donor tissue — restoring the joint with real human cartilage instead of metal and plastic. Patients return to running, cycling, hiking, and competitive sport. One patient went on to run several marathons after this procedure.
Dr. Mirzayan has performed BioPFJ™ in approximately 75 patients — more than any other surgeon in the world. No metal. No plastic. No permanent activity restrictions.
To find out if you are a candidate, call (310) 746-5918 or request a consultation online. Virtual consultations are available for patients traveling from Las Vegas, Henderson, Phoenix, Scottsdale, or anywhere in the world.
Understanding the Problem: The Patellofemoral Joint
The patellofemoral joint is formed by two structures: the patella (kneecap) and the trochlea — the groove at the end of the thigh bone where the kneecap glides. This joint bears forces several times body weight with every stair climbed, every squat performed, every mile run. When the cartilage here is damaged or destroyed, the result is deep, aching kneecap pain, grinding, swelling, and eventually the inability to perform basic daily activities.
Two very different groups of patients develop this condition.
Young patients with recurrent patellar instability are typically in their teens and 20s, often born with a shallow or malformed trochlear groove — a condition called trochlear dysplasia. This causes the kneecap to repeatedly dislocate or slide out of place. Each dislocation damages the cartilage further. By the time many of these patients seek care, the cartilage of both the kneecap and groove is severely damaged — at an age when a traditional knee replacement is simply not an acceptable answer. These patients are typically told to manage their symptoms or offered procedures that do not address the underlying cartilage loss.
Active middle-aged patients with isolated patellofemoral arthritis are typically in their 40s and 50s, with arthritis confined specifically to the kneecap compartment while the rest of the knee remains healthy. Traditional total knee replacement sacrifices the entire joint to address one compartment. A patellofemoral replacement uses metal and plastic components that restrict high-impact activity. Neither option is appropriate for an active patient who wants to return to sport.
For both groups, BioPFJ™ offers what no other treatment can: a complete biological reconstruction using real human cartilage from a carefully matched donor.
The Invention: What Is BioPFJ™?
BioPFJ™ stands for Biologic Patellofemoral Joint reconstruction. It is a procedure Dr. Mirzayan developed and pioneered involving the simultaneous transplantation of fresh osteochondral allograft tissue to both the patella and the trochlea — replacing the entire patellofemoral joint surface with living biological tissue from a single matched donor.
The patella component: The damaged cartilage surface of the patient's kneecap is carefully removed, preserving the underlying bone. A fresh donor kneecap — precisely matched in size and shape — is prepared and its cartilage surface secured directly onto the patient's remaining patellar bone using compression screws. The result is a perfectly shaped, living cartilage surface where metal and plastic were once the only option. Dr. Mirzayan demonstrated this technique in a surgical video produced by Arthrex: Fresh Allograft OATS Technique for Biologic Resurfacing of the Patella
The trochlea component: The damaged groove is simultaneously replaced with the trochlear graft from the same donor. Dr. Mirzayan demonstrated this technique in a second Arthrex surgical video: Allograft OATS Technique of the Trochlea
Why the same donor matters — and why this is the critical insight: Because both grafts come from the same donor, the articular surfaces are perfectly congruent. The kneecap and groove fit together exactly as nature intended — matched in geometry, curvature, and cartilage thickness — in a way that no metal or plastic implant can replicate, and in a way that mismatched grafts from different donors cannot achieve. This is what sets BioPFJ™ apart from every other cartilage restoration technique applied to this joint.
In patients with trochlear dysplasia, the donor trochlea also corrects the underlying anatomical abnormality — a shallow or malformed groove — something no other procedure achieves while simultaneously addressing the cartilage damage.
Dr. Mirzayan presented his full bipolar osteochondral allograft experience in a comprehensive Arthrex educational presentation available here: Bipolar Fresh Osteochondral Allograft Transplantation of the Patella and Trochlea
Why This Is Revolutionary
Even surgeons who regularly perform osteochondral allograft transplantation consider patellofemoral joint reconstruction one of the most technically demanding procedures in cartilage surgery. The complex three-dimensional geometry of the kneecap and groove makes sizing, preparation, and fixation extraordinarily challenging. Most cartilage surgeons do not attempt this procedure at all — and none have the experience Dr. Mirzayan has accumulated.
With approximately 75 cases performed, Dr. Mirzayan has established a depth of experience with BioPFJ™ that simply does not exist anywhere else in the world.
The outcomes speak for themselves:
100% graft integration of the patella — the donor kneecap has healed successfully to the patient's remaining patellar bone in every single case, a result that was not taken for granted given historical concerns about blood supply to the patella. No revisions. No conversions to joint replacement. Dramatic, statistically significant improvements across every functional outcome measure — KOOS, IKDC, Tegner-Lysholm, Oxford, Cincinnati, VAS pain, and SANE scores all improved significantly (P
Published Evidence
Dr. Mirzayan published the first outcomes study of bipolar osteochondral allograft transplantation of the patella and trochlea — the largest cohort of its kind in the scientific literature at the time — in the peer-reviewed journal Cartilage in 2018. The study demonstrated significant improvement across all functional outcome scores with 100% graft survival. It was also the first published report of osteochondral allograft transplantation being used to address trochlear dysplasia.
Read the full study in Cartilage (2018)
His series has since grown to approximately 75 patients with continued outstanding results.
Who Is a Candidate?
Group 1 — Young patients with recurrent patellar instability and cartilage damage: Typically teens to early 30s with a history of multiple kneecap dislocations, documented trochlear dysplasia, cartilage damage to the kneecap and groove from repeated dislocations, and inadequate response to prior stabilization procedures.
Group 2 — Active patients with isolated patellofemoral arthritis: Typically in their 40s to mid-50s with isolated arthritis of the kneecap compartment, a healthy remainder of the knee, and a desire to return to an active lifestyle including sport and athletics — unwilling to accept the permanent restrictions of a traditional joint replacement.
What to Expect
Surgery is performed as an open outpatient procedure under general anesthesia. Patients are non-weightbearing for 4 weeks following surgery to protect the healing grafts. Range of motion begins immediately — continuous passive motion is initiated from day one with no restriction. Strengthening begins as soon as possible with progressive return to activity. Full return to high-demand athletic activity typically occurs at 6 to 9 months. Patients have returned to running, cycling, tennis, and marathon competition.
Coming from Las Vegas, Phoenix, or Out of State?
Dr. Mirzayan regularly treats patients from Las Vegas, Henderson, Phoenix, Scottsdale, and across the country and the world. BioPFJ™ is available at one location, performed by one surgeon. There is no local alternative for this procedure — because no other surgeon has developed it, refined it, published it, or performed it at this volume.
If you carry a commercial insurance plan — Blue Cross Blue Shield PPO, Aetna, Cigna, United Healthcare, or a self-funded employer plan — you likely have out-of-network benefits that cover a substantial portion of the cost of surgery. Dr. Mirzayan's office will verify your coverage before you commit to anything. Many patients find the out-of-pocket cost of traveling to Los Angeles for the right surgeon is comparable to — or less than — what they would pay locally for in-network care.
Virtual consultations are available. You can submit your MRI and records in advance, meet Dr. Mirzayan on video, and determine whether making the trip is the right next step before committing to travel or time off work.
Call (310) 746-5918 or contact us online to schedule your consultation.
Frequently Asked Questions
What does BioPFJ™ stand for?
BioPFJ™ stands for Biologic Patellofemoral Joint reconstruction — a complete biological resurfacing of the kneecap and its groove using fresh donor tissue from a single matched donor.
Is this a knee replacement?
No. BioPFJ™ uses no metal or plastic components. The entire joint surface is reconstructed with living biological tissue from a human donor. There are no permanent activity restrictions and no implant that will wear out over time.
Why does using the same donor for both grafts matter?
The kneecap and groove must fit together with precise congruency. Because both grafts come from the same donor, they are naturally matched in geometry, curvature, and cartilage thickness — the way a biological joint is designed to work. Procedures using mismatched grafts from different donors cannot achieve this, which is one reason prior attempts at patellofemoral allograft reconstruction had higher failure rates. This single-donor approach is the central insight behind BioPFJ™.
How many of these procedures has Dr. Mirzayan performed?
Approximately 75 — more than any other surgeon in the world. His published outcomes study in the journal Cartilage (2018) was the largest bipolar patellofemoral allograft series in the scientific literature at the time of publication.
What are the outcomes?
100% graft integration of the donor kneecap in every single case. No patient has required revision or conversion to a traditional joint replacement. All functional outcome scores — KOOS, IKDC, Tegner-Lysholm, Oxford, Cincinnati, VAS pain, and SANE — improved significantly (P
Can BioPFJ™ also fix my trochlear dysplasia?
Yes — and this is one of the most important advantages of the procedure. In patients with a shallow or malformed trochlear groove, the donor trochlea corrects the underlying anatomical deformity while simultaneously replacing the damaged cartilage. No other procedure achieves both goals at once. Dr. Mirzayan's 2018 publication in Cartilage was the first report of osteochondral allograft transplantation being used to address trochlear dysplasia.
I was told I need a kneecap replacement. Could BioPFJ™ be an option instead?
Possibly. If your arthritis is isolated to the patellofemoral compartment and the rest of your knee is healthy, BioPFJ™ may be an appropriate alternative. Dr. Mirzayan evaluates each patient individually. Virtual consultations are available — call (310) 746-5918.
Can I see the surgical technique before deciding?
Yes. Dr. Mirzayan produced three educational videos with Arthrex demonstrating the procedure: the patella resurfacing technique, the trochlea resurfacing technique, and a comprehensive presentation on bipolar osteochondral allograft transplantation. Links to all three are included in the procedure description above. Dr. Mirzayan encourages informed patients.
Do you see patients from outside Los Angeles?
Yes. Dr. Mirzayan welcomes patients from Las Vegas, Henderson, Phoenix, Scottsdale, and from around the world. Virtual consultations are available. Call (310) 746-5918.
Is this covered by insurance?
Osteochondral allograft transplantation is typically a covered procedure under commercial insurance. Dr. Mirzayan is an out-of-network surgeon, but many patients with PPO plans or self-funded employer plans have strong out-of-network benefits — in some cases equivalent to in-network coverage. His team will verify your benefits before your consultation so you have a clear picture of costs before making any decisions.
About Dr. Raffy Mirzayan
Dr. Raffy Mirzayan, MD is a double-board certified orthopedic sports medicine surgeon, the inventor of BioPFJ™, and the world's leading expert on biologic patellofemoral joint reconstruction. He developed the procedure, published the foundational science, demonstrated the technique in peer-reviewed surgical education, and has performed it in more patients than any other surgeon on earth. His 2018 outcomes study in Cartilage — the first published series of bipolar osteochondral allograft transplantation of the patella and trochlea — established the evidence base for this procedure and introduced, for the first time, the use of allograft transplantation to correct trochlear dysplasia. For patients with patellofemoral joint disease who want a biological solution — not a metal and plastic replacement — there is one surgeon who invented this procedure, proved it works, and has the experience to deliver it. Dr. Mirzayan practices at DOCS Health in Los Angeles, serves as a Clinical Professor of Orthopaedic Surgery at USC, and welcomes patients from across the United States, including Las Vegas, Phoenix, and Scottsdale, for virtual consultations and in-person care.
DOCS Health | 8436 W 3rd St #800, Los Angeles, CA 90048 | (310) 746-5918 | raffymirzayan.com
