Knee Arthroscopy for a Meniscus Tear: Trimming vs. Repair, 44 Questions Patients Ask

Both are done by knee arthroscopy, which uses a small camera and instruments placed through small incisions. In a partial meniscectomy (“trimming”), the surgeon removes only the torn, unstable piece and keeps as much healthy meniscus as possible. In a meniscus repair, the torn edges are stitched together so the tissue can heal. Knee arthroscopy for meniscus tears, both partial meniscectomy and meniscus repair, is among the procedures Dr. Dold performs most often. For background on the meniscus itself, see our meniscus tear Q&A.

Not every tear can heal. Many tears, especially in the inner part of the meniscus or in worn, frayed tissue, will not knit back together even when stitched. Trying to repair tissue that cannot heal adds a longer recovery without the benefit. International guidelines say the meniscus should be preserved whenever possible, which means repairing the tears that have a reasonable chance of healing.¹

Tears that run lengthwise along the meniscus (vertical or longitudinal tears, including bucket-handle tears) are the classic repairable tears, and some radial tears can be repaired too.¹ Tears near the outer edge heal better than tears toward the inner edge. Horizontal, flap and complex tears in worn tissue are more often trimmed. Dr. Dold will explain what your MRI shows, but the final decision often depends on what the tear looks like during surgery.

Surgeons divide the meniscus by its blood supply. The red-red zone is the outer rim, which has a good blood supply and the most healing potential. The red-white zone is the middle area, with some blood supply at its outer edge. The white-white zone is the inner part, with little or no blood supply. Blood brings healing cells, so tears in the red zones are more likely to heal after repair than tears in the white zone.

Age alone is not the deciding factor. A review of repairs in patients 40 and older found a failure rate of about 12%, and the authors concluded that age by itself should not rule out repair.² Tissue quality matters more. Older knees are more likely to have worn, degenerative tears, which are less often repairable.

Active people, especially younger athletes, have the most to gain from keeping their meniscus because they will load the knee for decades. A longer recovery is the price of a repair. Dr. Dold will talk with you about your sport or work, your goals and how much time you can commit to a protected recovery.

Yes. A torn ACL lets the knee shift abnormally, which puts extra stress on the meniscus, so repairable meniscus tears are usually repaired at the same time as the ACL reconstruction.¹ A stable knee also protects the repair while it heals. In one review, a repair done with an ACL reconstruction was less likely to fail.³ See our ACL surgery Q&A.

The meniscus is a shock absorber that spreads load across the cartilage. Removing part of it concentrates the load on a smaller area. In a long-term study of traumatic tears, 80.8% of knees showed no progression of arthritis on X-ray after repair, compared with 40.0% after partial meniscectomy, and 96.2% of repair patients returned to their previous activity level vs 50% after meniscectomy.⁴ A systematic review also found better function scores and less arthritis on imaging after repair, although repairs needed more second surgeries.³

Often, but not always. An MRI shows the tear’s location and pattern, but the tissue quality and exact shape are clearest when the surgeon can see and probe the tear during arthroscopy. Dr. Dold will usually discuss both possibilities with you beforehand, so you are prepared for either recovery.

Most patients have general anesthesia, and some also receive a nerve block, an injection that numbs part of the leg for several hours after surgery. The anesthesia team will meet you on the day of surgery, review your health history and explain the plan that suits you.

The surgery itself is commonly about an hour or less for a trim. A repair usually takes longer because stitches are placed across the tear. Expect to spend a few hours at the surgery center or hospital in total, including check-in and recovery.

Yes. Meniscus surgery is outpatient surgery, so you go home the same day. You will need an adult to drive you home and, ideally, to stay with you for the first night.

Arthroscopy is usually done through two or three small incisions around the front of the knee, commonly about a centimeter long. Some repair techniques need an extra small incision on the side of the knee to tie the stitches. The incisions are closed with stitches or tape strips and covered with a dressing.

Keep the dressing clean and dry and follow your discharge instructions about when you may remove it and shower. A small amount of pinkish fluid on the dressing in the first day or two is common, because fluid is used to fill the knee during arthroscopy. Do not soak the knee in a bath, pool or hot tub until the incisions have healed and you have been cleared.

Rest with the leg raised above the level of your heart, use ice or a cold-therapy device as directed, and take pain medication as prescribed. Gently tighten your thigh muscle and pump your ankle often to keep blood moving. Use your crutches, and your brace if you have one, exactly as instructed.

Ask about it at your first visit after surgery. Dr. Dold will go over what was found and whether the tear was trimmed or repaired, and what that means for your recovery.

Weight bearing and deep bending squeeze and twist the meniscus. Early on, those forces can pull the stitches apart before the tissue has healed. Limiting weight, limiting how far the knee bends and avoiding deep squats and twisting for several months protect the repair while it heals.⁵

Both. Guidelines recommend moving through rehabilitation based on reaching goals, such as near-full motion, no swelling and good thigh-muscle control, rather than only on the calendar.⁵ Timelines vary from person to person, and Dr. Dold will give you a specific plan.

You should not drive while taking opioid pain medication, while wearing a brace on your driving leg, or until you can brake hard and quickly without hesitation. For the left knee in an automatic car, driving is commonly possible sooner. For the right knee, it commonly takes 1 to 2 weeks after a trim and about 6 weeks after a repair. Timelines vary from person to person, and Dr. Dold will give you a specific plan.

It depends on your job. People with desk jobs commonly return within about a week after a trim and 1 to 2 weeks after a repair. Jobs that involve standing all day, kneeling, squatting, climbing or lifting take longer, especially after a repair. Our office can provide work notes and light-duty restrictions. Timelines vary from person to person, and Dr. Dold will give you a specific plan.

After a trim, return to sport commonly takes about 4 to 12 weeks.⁵ After a repair, a gradual return to running commonly starts at about 3 to 4 months, and a return to pivoting and cutting sports at about 4 to 6 months or later.⁵ In a review of athletes, 83.1% returned to play after an isolated meniscus repair, although the time it took varied widely between studies.⁶ Timelines vary from person to person, and Dr. Dold will give you a specific plan.

Do your home exercises, go to physical therapy, control swelling with ice and elevation, and follow your weight-bearing and bending limits exactly. After a repair, the most common mistake is doing too much too soon because the knee feels good before the tissue has fully healed.

Most repairs succeed, but not all. In a review of repairs followed for at least 5 years, about 23% had failed,⁷ and a second review with at least 5 years of follow-up found that about 19% had been revised.⁸ Individual results vary, and the type and location of your tear affect your chances.

Yes. In a review of meniscus repairs followed for at least 5 years, 36% of failures occurred after the second year.⁸ This is one reason Dr. Dold may continue to check on your knee after you are back to full activity.

Yes. In a systematic review, about 20.7% of isolated repairs needed another operation in long-term follow-up, compared with about 3.9% of partial meniscectomies.³ In exchange, the repaired knees had better function scores and less arthritis on imaging.³ That trade-off is at the heart of the trim-or-repair decision.

Symptoms such as catching, locking, swelling or pain along the joint line can return. Dr. Dold will examine you and may order imaging. Depending on the tear, the failed portion may be trimmed, or in selected cases repaired again.

Results of partial meniscectomy are generally better for tears caused by an injury than for degenerative (wear-related) tears, both for symptoms and for arthritis progression over the long term.⁹ For degenerative tears, the evidence below explains why surgery is usually not the first step.

A tear that develops slowly as the meniscus weakens with age, often with no clear injury or after a simple movement such as squatting. These tears are very common in people over about 40 and often occur alongside early knee osteoarthritis.

In the Finnish FIDELITY trial, 146 people aged 35 to 65 with a degenerative medial meniscus tear and no knee arthritis had either a partial meniscectomy or a sham (placebo) surgery. Both groups improved, and there were no significant differences between them at 12 months.¹⁰ This does not mean the knee pain was imagined. It means that much of the improvement came from factors other than removing the torn tissue.

In the METEOR trial, 351 people aged 45 and older with a meniscus tear and mild to moderate arthritis improved by similar amounts with surgery or physical therapy at 6 months, although 30% of the physical therapy group switched to surgery within 6 months.¹¹ In the ESCAPE trial, 321 people aged 45 to 70 with tears that were not locking the knee did about as well with physical therapy as with surgery over 2 years, and 29% of the therapy group later had surgery.¹²

International guidelines recommend that partial meniscectomy should not be the first treatment for degenerative tears. Non-surgical care such as physical therapy comes first, and surgery is considered when symptoms do not improve.¹³

Surgery may be considered when symptoms continue despite a good course of therapy, or when a torn fragment physically blocks the knee so it cannot straighten (a truly locked knee). The ESCAPE trial did not include knees that were locked in this way.¹² Occasional catching or brief locking from a degenerative tear did not improve more after meniscectomy than after sham surgery in one analysis,¹⁴ so these symptoms alone are not always a reason for surgery. Dr. Dold will weigh your exam, X-rays and MRI with you.

Serious complications are uncommon. In a large Swedish study, the risk of one or more complications within 30 days of knee arthroscopy was about 1.1%; blood clots and joint infection were among the complications studied.¹⁵ Dr. Dold will review your individual risks before surgery.

Blood clots are uncommon but important. In a large US database of nearly 139,000 arthroscopic knee procedures of many kinds, a clot in a leg vein (deep vein thrombosis) was reported in about 0.57% and a clot in the lungs (pulmonary embolism) in about 0.12%.¹⁶ Moving your ankles, walking as allowed and following your medication instructions help lower the risk. Tell Dr. Dold if you or a family member have had a blood clot.

A joint infection after arthroscopy is rare but serious and needs prompt treatment.¹⁵ Stiffness can occur, especially after a repair when bending is limited for several weeks, which is why physical therapy and home exercises matter. Other possible problems include numbness near the incisions, persistent swelling and a repair that does not heal.

Call 469-850-0680 if you have a fever or chills, increasing redness, warmth or cloudy drainage from an incision, increasing calf pain, tenderness or swelling, pain that your medication does not control, or new catching or locking. If you call during office hours, our staff will call and text you within an hour (Monday–Friday, 8 am–5 pm).

Call 911 or go to the nearest emergency room for chest pain, shortness of breath, coughing up blood or a racing heartbeat, which can be signs of a blood clot in the lungs.

Dr. Dold accepts most major insurance plans, including Medicare and Tricare. Please call 469-850-0680 to confirm your coverage. Many plans require pre-authorization for surgery and MRI; see our insurance page and our surgery scheduling and insurance Q&A.

Plan around the longer recovery if a repair is possible, because you may not know until surgery which procedure you will have. That means arranging for about 6 weeks on crutches, help at home for the first few days, rides if your right knee is involved, and a work plan for both possibilities. Timelines vary from person to person, and Dr. Dold will give you a specific plan.

Practice walking with crutches before surgery, clear tripping hazards at home, set up a place to rest with the leg raised, and have ice packs ready. Give Dr. Dold’s team a full list of your medications, including blood thinners and supplements, and follow the facility’s instructions about eating and drinking before surgery.

A second opinion is reasonable for any planned surgery, and Dr. Dold welcomes patients seeking one. Bring your MRI images (not only the report), your X-rays and any surgical or therapy notes. To schedule, request an appointment or call 469-850-0680.

For many tears, yes, especially degenerative tears. For tears from an injury in younger, active people, especially large or displaced tears, waiting can sometimes let the tear grow or the tissue worsen, which may make repair less likely. Dr. Dold will tell you whether there is a reason not to delay.

See our pages on meniscus tears and arthroscopic meniscus repair, and our broader meniscus tear Q&A, which covers anatomy, diagnosis, root tears and meniscus transplant.