Can PRP Injections Actually Heal a Meniscus Tear?

The meniscus has notoriously poor blood supply, and most tears — especially degenerative ones — never fully heal on their own. For years, patients with persistent meniscus tears have been told that surgery is the only viable option. But what if we could change the biology inside the knee to make healing possible?

As a sports medicine physician in the San Francisco Bay Area, I regularly treat patients who come in for a second opinion after being told they need surgery for a meniscus tear. In many of these cases, the tear is degenerative rather than traumatic, and the evidence increasingly supports non-surgical treatment as a first-line approach. In this article, I review what the research actually says about platelet-rich plasma (PRP) treatments for meniscus tears — and whether PRP can truly help the tissue heal, or if it simply provides pain relief.

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Why Meniscus Tears Are So Difficult to Heal

The meniscus plays a critical role in knee function. It cushions impact, distributes load across the joint, and provides stability during movement. However, when the meniscus tears — particularly from age-related wear or repetitive stress — healing becomes a major challenge.

The reason comes down to blood supply. Only the outer one-third of the meniscus, known as the "red zone," actually receives blood flow. The inner two-thirds, called the "white zone," is completely avascular. Without blood flow, there is no efficient mechanism to deliver oxygen, nutrients, or the repair cells needed for tissue healing. Small tears in the outer edge can sometimes heal on their own, while deeper tears in the avascular zone almost never do.

Why Surgery May Not Be the Best Answer for Degenerative Meniscus Tears

For years, surgeons addressed meniscus tears by removing the damaged portion through a procedure called arthroscopic partial meniscectomy. However, multiple randomized controlled trials have now shown that for degenerative tears, this surgery does not perform any better than sham (placebo) surgery when it comes to reducing pain or improving function.

Even more concerning, removing meniscal tissue can accelerate cartilage wear and increase the risk of developing early-onset osteoarthritis. This creates a frustrating clinical situation: the meniscus is essential for long-term knee health, yet it has very limited capacity to repair itself. This is precisely what makes biological treatments like PRP so promising — instead of cutting tissue out, the goal is to change the environment inside the knee to support healing.

How Platelet-Rich Plasma (PRP) Works for Meniscus Injuries

PRP is produced by drawing a small sample of a patient's own blood and spinning it in a centrifuge to concentrate the platelets. These platelets contain a dense concentration of growth factors that activate the body's natural repair processes. When injected into damaged tissue, PRP releases a cascade of healing signals that attract repair cells, promote new blood vessel formation, and stimulate collagen and extracellular matrix production.

In the context of meniscus injuries, PRP is particularly appealing because it has the potential to turn on a healing response in tissue that normally lacks the biological machinery to repair itself. In my practice, I use PRP injections as part of a comprehensive, evidence-based treatment approach for patients with meniscus tears who want to explore non-surgical options.

What the Research Shows: PRP Combined with Percutaneous Trephination

One of the most compelling studies on PRP for meniscus tears is a randomized, double-blind, placebo-controlled trial by Kaminski et al. (2019) published in the International Journal of Molecular Sciences. This study enrolled 72 patients with chronic degenerative meniscus tears. Every patient underwent an ultrasound-guided minimally invasive procedure called percutaneous trephination, in which tiny needle punctures are made through the meniscus to stimulate bleeding and bring in new healing factors.

Half of the patients then received a leukocyte-rich PRP injection — with an average of approximately 5 to 7 billion total platelets — delivered directly into the meniscus under ultrasound guidance. The other half received a saline placebo injection. Patients were followed for nearly two years with MRI scans and detailed pain and function assessments. The goal was not only to see if symptoms improved, but to confirm whether the meniscus tissue actually showed signs of structural healing.

Key Findings from the Randomized Controlled Trial

The results of this trial were significant. The PRP group demonstrated a markedly higher healing rate compared to the control group. When combining both MRI and arthroscopic evaluation data, 52% of menisci in the PRP group healed, compared to only 30% in the control group — representing a nearly 75% relative improvement in healing.

Perhaps even more clinically meaningful, the need for future surgery dropped substantially. Only 8% of patients in the PRP group went on to require arthroscopy, compared to 28% of those who received saline. That means PRP helped many patients avoid surgical intervention entirely.

Pain and function outcomes also favored PRP. A clinically meaningful reduction in pain, as measured by the Visual Analog Scale (VAS), was achieved by 65% of PRP-treated patients compared to 39% in the control group. On the KOOS symptoms subscale, which evaluates stiffness, swelling, and mechanical catching, 76% of PRP patients reached a meaningful improvement versus 48% in the control group.

Importantly, no complications were reported — no infections, no worsening of symptoms, and no adverse effects from the injection. The combination of mechanical stimulation from trephination and biological activation from PRP appears to change the environment inside the meniscus from one that cannot heal to one that can.

Supporting Evidence from Systematic Reviews

The findings of this randomized controlled trial are further supported by broader meta-analytic data. A 2025 systematic review and meta-analysis by Liang et al., published in the Orthopaedic Journal of Sports Medicine, compiled data from 18 randomized controlled trials involving 1,143 patients with meniscal injuries. The researchers found that PRP significantly reduced knee pain and improved knee function compared to control treatments. Specifically, patients who received PRP demonstrated higher Lysholm scores, improved KOOS scores, and lower WOMAC scores. The meta-analysis also found that PRP reduced treatment failure rates, and no significant difference in complication rates was observed between the PRP and control groups.

These pooled results across multiple trials reinforce the conclusion that PRP is not simply masking pain — it appears to promote actual biological improvement in meniscal tissue.

What This Means for Your Treatment Options

These results are important because they suggest that PRP is contributing to actual tissue repair, not just symptom management. Even in cases where the meniscus did not show complete structural healing on MRI, patients still experienced less pain and better function — indicating that at least partial biological repair was occurring. Improvement in pain and function without surgery suggests the meniscus may be regaining some of its load-bearing and shock-absorbing properties.

The main clinical takeaway is this: if you have been told your only option is surgery, but your tear is degenerative and not severe, PRP may be a legitimate, evidence-based alternative worth considering first. It is minimally invasive, carries a low risk of complications, and in the Kaminski trial, helped more than half of patients achieve real biological healing.

Recovery After PRP Treatment for a Meniscus Tear

While PRP can help jumpstart the healing process, what you do afterward matters just as much. Movement and targeted strengthening exercises are essential for helping newly repaired tissue adapt and remain healthy. A structured rehabilitation program should protect the joint in the early stages while progressively rebuilding strength, stability, and range of motion. In my practice, I work closely with patients to develop individualized rehab protocols that match the severity of their tear and their activity goals.

Schedule a Consultation

If you have a meniscus tear and want to explore non-surgical treatment options, I offer comprehensive evaluations including diagnostic ultrasound and personalized treatment plans. To learn more about PRP and other orthobiologic treatments, visit my PRP injection services page or schedule an appointment today.

References

1. Kaminski R, Maksymowicz-Wleklik M, Kulinski K, et al. Short-Term Outcomes of Percutaneous Trephination with a Platelet Rich Plasma Intrameniscal Injection for the Repair of Degenerative Meniscal Lesions. Int J Mol Sci. 2019;20(4):856. doi:10.3390/ijms20040856

2. Liang J, Tu M, Li H, Chen W, Wang C. Efficacy and Safety of Platelet-Rich Plasma for Patients With Meniscal Injury: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Orthop J Sports Med. 2025;13(10):23259671251371233. doi:10.1177/23259671251371233

Author: Dr. Jeffrey Peng, MD — Board-Certified Sports Medicine Physician, San Francisco Bay Area

Published: March 1, 2025 | Last Updated: March 1, 2025