Red Light Therapy for Meniscus Tear: What Two Trials Found

Red light therapy for meniscus tear pain has two small placebo-controlled trials behind it, and in both, near-infrared laser light on the inner side of the knee eased pain and improved knee scores more than placebo. Neither trial checked whether the tear healed, and light does not repair cartilage, so it fits best as an add-on to physiotherapy. Below: the two trials, degenerative versus sport tears, timing after a twist or arthroscopy, warning signs, where to aim and panel set-up.

Key takeaways

• In a 2013 double-blind trial of 64 people with small medial meniscus lesions, 904 nm laser light over 9 sessions in 6 weeks eased pain significantly more than placebo. Malliaropoulos, 2013
• In a 2026 trial of 40 people who all did six weeks of physiotherapy, adding laser light lowered pain by 3.36 points out of 10, against 2.08 points with sham light. Alsirhani, 2026
• The meniscus is fibrocartilage, and only its outer third, the "red zone", has the blood supply that can let a tear heal on its own or be repaired. AAOS OrthoInfo
• In the ESCAPE trial of 321 people aged 45 to 70 with a degenerative tear, the authors concluded that physical therapy "should therefore be the preferred treatment over surgery". Noorduyn, 2022
• The NHS advises getting help from 111 if a painful knee "locks, gives way, or painfully clicks". NHS

Does red light therapy for meniscus tear pain help?

The evidence is small but favourable: two sham-controlled trials found less pain and better knee function when near-infrared laser light was aimed along the inner joint line. Both enrolled people with medial meniscus lesions and knee pain lasting at least six weeks, and neither measured whether the tear itself healed.

Trial	Who	What was added	What was found
Malliaropoulos, 2013	64 people with small medial meniscus lesions on MRI	904 nm laser or identical placebo, 9 sessions over 6 weeks	Pain fell significantly more with laser; Lysholm knee score 82.5 vs 79.0 at 4 weeks
Alsirhani, 2026	40 people aged 25 to 50 with an MRI-confirmed medial meniscus injury	904 nm laser or sham, both groups with six weeks of physiotherapy	Pain down 3.36 vs 2.08 out of 10; Lysholm up 4.70 vs 1.65 points

The Lysholm score is a standard knee function questionnaire. The 2013 trial registry reports that pain on a 100 mm scale fell by about 65% at four weeks with laser. ISRCTN registry, 2013 On the Lysholm score, the laser group still scored 82.2 at 6 months and 81.6 at 1 year.

The authors wrote: "Treatment with LLLT was associated with a significant decrease of symptoms". Malliaropoulos, 2013

The 2026 trial is closer to everyday care, because light was added to supervised exercise. The 20 metre walk got 24.8 seconds faster with laser, against 11.2 seconds with sham. Alsirhani, 2026 The author concluded that laser light "may be a useful adjunct to rehabilitation in individuals with knee meniscus injuries."

Can red light therapy heal a torn meniscus?

No: light does not repair cartilage, and the trials in people measured pain and function, not tear healing. What decides whether a tear can heal is mainly where it sits and how large it is.

AAOS describes the menisci as "two wedge-shaped pieces of fibrocartilage" that cushion the thigh bone and shin bone. AAOS OrthoInfo

• Red zone: the outer third has a blood supply, so a tear there may heal on its own or be stitched.
• White zone: the inner two-thirds has a limited blood supply, and painful tears there are usually trimmed.
• Size: Cleveland Clinic says small tears often heal on their own. Cleveland Clinic

Our guide to red light therapy for knee pain reaches the same view: nothing shows a tear healing, and no human trial shows cartilage regrowing. The goal for light is a more comfortable knee while exercise does its work.

Red or near-infrared: what light did the meniscus trials use?

Near-infrared: both trials used a 904 nm laser probe on the skin at 20 points over the inner joint line, for 420 seconds per knee. The 2013 trial gave 9 sessions over 6 weeks, and the 2026 trial ran alongside six weeks of physiotherapy.

Study	Light	Dose	Time	Sessions	Weeks
Malliaropoulos 2013, meniscus	904 nm laser, 240 mW	100.8 J per knee over 20 points	420 seconds per knee	2 a week for 3 weeks, then 1 a week for 3 weeks	6
Alsirhani 2026, meniscus	904 nm laser, 240 mW	2.52 J per point, 100.8 J per knee	10.5 seconds per point	Not stated, with physiotherapy	6
Stausholm 2019, knee osteoarthritis review	785 to 860 nm or 904 nm lasers	4 to 8 J per spot, or 1 to 3 J at 904 nm	Varied	Mostly 2 to 3 a week	3 to 6

The osteoarthritis row comes from a review of 22 placebo-controlled trials with 1,063 people. Stausholm, 2019 Laser joules per point do not convert into panel minutes. What carries over is the pattern: near-infrared light on the skin over the joint line, regularly, for about six weeks.

Near-infrared reaches deeper into tissue than red. Our panel's near-infrared channels are 810, 830, 850 and 1060 nm, and 810, 830 and 850 nm sit inside the 785 to 860 nm band from the osteoarthritis review. Run near-infrared high and red lower, as our knee and joint guides do.

I am over 40 with a degenerative tear: does light replace physio or surgery?

No: for degenerative tears, exercise therapy comes first, and light sits alongside it. Many of these tears settle with time and a good exercise programme.

Mayo Clinic says wear in older knees can lead to a tear "with little or no trauma". Mayo Clinic It also notes that "Tears associated with arthritis often improve over time with treatment of the arthritis". Mayo Clinic

• ESCAPE trial: 321 people had 16 physiotherapy sessions over 8 weeks or a partial meniscectomy. Over 5 years of follow-up, surgery was ahead by only 3.5 points on a knee score, inside the 11-point margin. Noorduyn, 2022
• Later surgery: 52 of 162 people in the physiotherapy group, 32.1%, went on to have an operation.
• Consensus: the EU and US meniscus rehabilitation consensus makes physiotherapy the first approach for degenerative lesions, at its top grade. ESSKA consensus, 2024

Degenerative tears often sit alongside knee osteoarthritis. There, the 2019 review found pain 14.2 mm lower than placebo on a 100 mm scale, and 18.7 mm lower at recommended doses; our knee pain article covers those trials.

When can you use red light after twisting your knee?

From about day 3, once the first days of rest, ice and elevation are over and warning signs have been checked. A suspected tear after a sports injury is worth an assessment, because younger people with outer-zone tears may be offered a repair.

The same timing applies to red light therapy for knee injury more generally, as our guide to red light therapy for injuries explains.

• Ice: the NHS suggests an ice pack or frozen peas in a tea towel "for up to 20 minutes every 2 to 3 hours". NHS
• Swelling builds: AAOS notes that "Over 2 to 3 days" the knee becomes stiffer and more swollen. AAOS OrthoInfo
• Ice and light: use them on separate occasions, and after ice let the skin return to normal temperature and feeling before a light session.

Which knee symptoms need an orthopaedic assessment before any light?

A knee that locks, gives way, will not straighten or cannot take weight needs an orthopaedic assessment first. So does a knee that is badly swollen, hot and red, or comes with a fever.

• NHS 111: very painful, cannot move it or put weight on it, badly swollen or changed in shape, or it "locks, gives way, or painfully clicks". NHS
• Possible infection: a high temperature with redness or heat around the knee.
• Mayo Clinic: "Contact your doctor if your knee is painful or swollen, or if you can't move your knee in the usual ways." Mayo Clinic
• Cleveland Clinic: you cannot fully bend or straighten the leg without pain, or swelling has not improved after a few days. Cleveland Clinic
• No progress: the NHS suggests seeing a GP if knee pain has not improved within a few weeks.

The EU and US consensus refers mechanical signs such as locking to a surgeon.

How soon after meniscus surgery can you use red light?

Only once every small cut has fully closed, the stitches or tape are off, and your surgeon agrees. Never use light over stitches, tape or a wound that has not closed.

The NHS says knee arthroscopy cuts are "around 2mm to 3mm wide", closed with tape or stitches. NHS Cleveland Clinic says the incisions generally heal within a week or two. Cleveland Clinic

• Rehabilitation: AAOS gives about 3 to 6 weeks after a partial meniscectomy and 3 to 6 months after a repair.
• Braces: never take a brace off to use light unless your surgeon or physiotherapist agrees.
• Warning signs: the NHS lists a high temperature, severe or increasing pain, smelly liquid from the cut, or worsening swelling or redness.

The closest evidence after surgery comes from knee replacement trials, where light was added to rehabilitation; see red light therapy after knee replacement. Our after surgery guide has the full "not yet" checklist.

Where should you aim the light for a medial or lateral meniscus tear?

For a medial tear, aim at the inner side of the knee along the joint line, as both trials did. For a lateral tear, turn the outer side of the knee toward the light, then light the front.

The joint line is the soft gap you can feel at each side of the knee, just below the kneecap, with the knee slightly bent. Both trials placed 20 points in two rows over it. Not sure which side? Ask your physiotherapist.

Trial lasers touch set points; a panel lights a broad area from a short distance. Our article on cold laser therapy vs red light therapy explains the difference.

How long before you notice a difference?

The trials measured their gains at 4 and 6 weeks, so judge a home routine at three to four weeks. Keep in mind that many minor tears settle with time and exercise anyway.

Baylor Scott & White gives about 4 to 8 weeks for initial healing of a minor tear without surgery, and 3 to 6 months for full recovery. Baylor Scott & White

Log pain out of 10 each morning, plus stairs and squatting. At 3 to 4 weeks, continue only if the log shows progress, and see your physiotherapist or GP if it does not.

Can you use red light over a knee brace, or with ibuprofen?

Light needs bare skin, because a sleeve, brace or bandage blocks most of it. Medicines are a separate question for your pharmacist or doctor.

Even one layer of dark fabric blocks most of the light. Take a sleeve off, but keep any brace your surgeon has told you to wear.

AAOS lists ibuprofen and naproxen among the usual first treatments, and both appear on lists of medicines that can make skin more sensitive to light. Our precautions rule out use with photosensitising medication, so anyone taking a medicine should check with their pharmacist or doctor before using the device.

How do you use a Kivorla panel on a torn meniscus?

Lower the panel to knee level, put the goggles on, and turn the painful side of the bare knee toward it at about 6 inches. Run near-infrared high and red lower for 10 to 15 minutes per area, 3 to 5 times a week, alongside your exercise programme.

The 9-Spectrum Red Light Therapy Panel carries 480, 590, 630, 660, 670, 810, 830, 850 and 1060 nm, each dimmable from 1 to 100%. At 6 inches it puts out at least 1,567 W/m². The Kivorla mask is a face device and is not meant for knees.

• Position: hang it low on a door or wall with the included door hook, pulley, hanging cables and screws, or stand it upright on the floor. Sit with the knee supported.
• Start gently: 5 to 10 minutes every other day at 12 inches, channels dimmed, for the first sessions.
• Build up: about 6 inches, 10 to 15 minutes per area, 3 to 5 times a week. One knee at a time.
• Channels: 810, 830, 850 and 1060 nm high; 630, 660 and 670 nm lower; 480 and 590 nm at their lowest or off; pulse off.
• Comfort: the surface stays at or below 40°C, so do not rest the knee on it. Warm is fine, hot means stop.
• Eyes: goggles on and eyes closed, even for the legs; never look into the panel. See red light therapy goggles.

The trials gave about 7 minutes of laser at set points. To stay gentle, use a shorter timer (it starts at 1 minute), dim the channels or step back to 12 inches. If no time is set, the panel stops at 5 minutes. Leave at least 6 hours between 30-minute sessions. Goggles and a controller are included.

Do not use the panel if you are pregnant, breastfeeding or preparing for pregnancy, have epilepsy or light-triggered seizures, have a thyroid condition or take thyroid medication, take photosensitising medication, have had sunburn on your body in the past 2 weeks, or have Fitzpatrick skin type V or VI. It is not for use by anyone asleep or unconscious, and never over broken skin, stitches or an unhealed cut.

Standard shipping to the US, UK and Germany is free. Read the precautions before ordering. Under our return and refund policy, returns are accepted within 30 days: an unopened device with its seals intact is refunded less a 10% restocking fee, and an opened device that is undamaged and complete is refunded less 20%.

Kivorla devices are general wellness devices, not medical devices, and are not intended to treat or repair a meniscus tear. See a doctor or orthopaedic specialist for a knee that locks, gives way or swells badly, and keep the exercise programme your physiotherapist has set.