When patients are told that a medial meniscus posterior root tear should be repaired, the next question is usually straightforward: what actually happens during the operation?

The concept is simple. The torn posterior root is brought back to the area of the tibia where it normally attaches and is secured there so that it can heal. The execution is less simple. The root sits at the back of a tight medial compartment, and the remaining meniscal tissue may already be fragile. Good visualization, accurate tunnel or anchor placement, careful suture passage and stable fixation all matter.

I perform the procedure arthroscopically. Standard anterior portals are used, but additional viewing access may be needed to see the posterior root directly. In selected knees, a posteromedial portal and a 70-degree arthroscope help define the native footprint more clearly. If the medial compartment is exceptionally tight, limited MCL pie-crusting can be used to improve working space rather than forcing instruments against the articular cartilage.

Once the footprint has been identified, it is prepared and the repair construct is created. In my usual transtibial technique, a guide pin is placed at the intended root attachment and a small tibial tunnel is reamed. High-strength sutures are then passed through the meniscal root. I prefer to create two cinch-type grasping constructs with as few tissue penetrations as possible.

That point deserves emphasis. The goal is not simply to place more sutures. Repeatedly passing a needle through degenerative meniscal tissue can damage the tissue that must ultimately hold the repair. I therefore try to plan the passes carefully and obtain a secure grasp with minimal additional trauma.

The suture limbs are brought through the tibial tunnel to the front of the tibia and tensioned while the root is reduced to bone. Several fixation methods are available. Cortical buttons are widely used. In my practice, I generally use a cortical screw and washer as a post and tie the two suture constructs sequentially. I like the ability to control the final tension while directly watching the root dock against the tibial footprint.

A different approach is to place a suture anchor close to the root and repair the meniscus without a long tibial tunnel. Recent biomechanical literature has generally favored suture-anchor constructs for stiffness and resistance to cyclic displacement. That does not yet mean that anchors are clinically superior in every patient. Comparative clinical studies, including recent data, have shown meaningful improvement with both anchor and transtibial techniques without a clear clinical winner.

The choice becomes particularly interesting when root repair is combined with high tibial osteotomy. A root tunnel and the screws from an osteotomy plate can intersect. This is not only a theoretical concern; imaging-based surgical simulation studies have demonstrated that the risk depends on tunnel exit and plate position. When I combine the procedures, I plan the tunnel and plate together and sequence the operation to minimize that conflict.

This is why medial meniscus root repair has a learning curve. The incisions are small, but the work inside the knee is precise. The surgeon has to create adequate working space, identify the correct footprint, protect the remaining meniscus, avoid unnecessary cartilage injury and maintain a stable reduction.

Technique, however, is only one part of the result. A technically well-executed repair cannot reverse advanced osteoarthritis or poor tissue biology. I first decide whether a patient is a reasonable candidate based on cartilage status, alignment, meniscal tissue quality, activity level and the ability to follow postoperative restrictions. If repair is appropriate, then precision in the operating room becomes the next priority.

For patients, the most useful way to think about root repair is not that the meniscus is simply ‘stitched.’ The operation is an attempt to restore the load-bearing root attachment as closely as possible while giving the tissue a realistic chance to heal.

References

Meng C, et al. Suture Anchor Technique Shows Superior Biomechanical Properties Compared With Transtibial Pull-Out for Posterior Medial Meniscus Root Repairs: A Systematic Review. Arthroscopy. 2026;42(7):1266-1281. PMID 41946450. DOI 10.1002/arj.70155.

Saengpetch N, et al. Radiologic and Clinical Analysis of Posterior Medial Meniscal Root Tears: A Comparative Study of All-Suture Anchor and Transtibial Pullout Techniques. Orthop J Sports Med. 2026;14(7):23259671261464696. PMID 42534383. DOI 10.1177/23259671261464696.

Kim JH, et al. Arthroscopic suture anchor repair versus pullout suture repair in posterior root tear of the medial meniscus: a prospective comparison study. Arthroscopy. 2011;27(12):1644-1653. PMID 21982389. DOI 10.1016/j.arthro.2011.06.033.

Robinson JR, et al. Knotless Anchor Fixation for Transosseous Meniscal Root Repair Using Suture Tape Is Inferior Compared With Button or Screw Fixation: A Biomechanical Study. Orthop J Sports Med. 2020;8(4):2325967120912185. PMID 32341928. DOI 10.1177/2325967120912185.

Krych AJ, et al. A simple cinch is superior to a locking loop for meniscus root repair: a human biomechanical comparison of suture constructs in a transtibial pull-out model. Knee Surg Sports Traumatol Arthrosc. 2018;26(8):2239-2244. PMID 28748490. DOI 10.1007/s00167-017-4652-1.

LaPrade RF, et al. Cyclic displacement after meniscal root repair fixation: a human biomechanical evaluation. Am J Sports Med. 2015;43(4):892-898. PMID 25556220. DOI 10.1177/0363546514562554.

Chang TY, et al. Biomechanical analysis of four different meniscus suturing techniques for posterior meniscal root pull-out repair: A human cadaveric study. J Exp Orthop. 2024;11(3):e70020. PMID 39318713. DOI 10.1002/jeo2.70020.

Nejima S, et al. Risk of interference between the tibial tunnel and locking screws in medial meniscus posterior root repair and open wedge high tibial osteotomy. J Exp Orthop. 2022;9(1):25. PMID 35292866. DOI 10.1186/s40634-022-00464-0.

Steineman BD, et al. Nonanatomic Placement of Posteromedial Meniscal Root Repairs: A Finite Element Study. J Biomech Eng. 2020;142(8):081004. PMID 31901167. DOI 10.1115/1.4045893.

Kotipalli S, et al. Pie-crusting the medial collateral ligament is a safe and effective technique for improving visualisation and access in arthroscopic meniscal surgery: A systematic review. Knee Surg Sports Traumatol Arthrosc. 2026;34(9):3298-3313. PMID 41144741. DOI 10.1002/ksa.70103.

How I think about medial meniscus posterior root tears in middle-aged and older adults

A common story is a patient in their 50s or 60s who had been doing reasonably well, then suddenly developed significant medial or posteromedial knee pain during an ordinary movement: hurrying across a street, stepping off a bus, or getting out of a car. The X-ray may show only mild arthritis. In that situation, one diagnosis I actively consider is a medial meniscus posterior root tear (MMPRT).

Why the “root” matters

I often explain the meniscus root using a tree analogy. A tree needs its roots firmly anchored in the ground. In the same way, the meniscus needs a secure attachment to bone to maintain tension and distribute load. When the posterior root is torn, the meniscus can extrude outward under weight bearing. The contact area decreases and focal contact pressure rises. Biomechanically, a complete root tear can behave much like loss of the functional meniscus [1].

Diagnosis: X-rays guide treatment, MRI confirms the tear

Weight-bearing radiographs are essential because they show the baseline osteoarthritis and alignment that will influence treatment. They do not, however, confirm a root tear. MRI is the key test for the tear itself and also shows meniscal extrusion, cartilage status, marrow edema, and subchondral insufficiency fracture of the knee (SIFK).

What happens if you do not have surgery?

This is the question patients ask most often. Symptoms and structural prognosis should be separated. Some patients become much more comfortable after a period of activity modification, medication, physical therapy, or injections. In my clinical practice, the acute pain can settle substantially over several months. But pain improvement does not mean that normal root function has returned.

Long-term observational data are concerning. In a Mayo Clinic cohort of degenerative MMPRTs treated nonoperatively, 87% met failure criteria by approximately 5 years and 31% had converted to total knee arthroplasty. At a minimum 10-year follow-up, 37 of 39 living patients (95%) met the study definition of failure [2,3]. These numbers should not be presented as inevitable for every patient, but they are strong reasons not to dismiss an MMPRT simply because pain becomes tolerable.

Who is a reasonable candidate for root repair?

Root repair is most attractive when the knee is still worth preserving: limited osteoarthritis, acceptable cartilage status, repairable meniscal tissue, and an alignment that does not overload the medial compartment. Systematic reviews generally favor repair over partial meniscectomy or nonoperative treatment for appropriately selected patients, with less radiographic progression and lower conversion to arthroplasty [4,5].

Age is a factor, not a stand-alone cutoff

I do not use chronological age alone as the decision. Recent cohorts show that appropriately selected patients older than 60 can improve after medial meniscus posterior root repair, with outcomes that are not necessarily inferior to younger patients [6,7]. Evidence specifically in patients in their 70s remains less robust, so the discussion should include uncertainty, rehabilitation burden, and the possibility of later arthroplasty.

Alignment can change the operation

Varus alignment increases medial compartment loading. In a younger or joint-preservation candidate with meaningful varus, high tibial osteotomy (HTO) may be considered with or without root repair. Recent systematic reviews suggest possible objective advantages from combining repair with HTO, but the incremental short-term clinical benefit is not completely settled [8].

When arthroplasty may be the better answer

If there is advanced cartilage loss, high-grade SIFK or collapse, or established compartmental osteoarthritis, simply repairing the root may be unlikely to solve the problem. In a properly selected isolated medial-compartment pattern, unicompartmental knee arthroplasty can be considered; with more widespread advanced osteoarthritis, total knee arthroplasty may be more appropriate. The key is not to force a “meniscus-preserving” operation onto a knee that has already progressed beyond that stage.

My decision sequence

Confirm the root tear and assess cartilage, extrusion, and SIFK on MRI.

Assess weight-bearing osteoarthritis and full-length limb alignment.

Decide whether the knee remains a realistic joint-preservation candidate.

If yes, choose between isolated root repair and alignment correction (HTO ± repair).

Assess tissue quality, activity level, work demands, and ability to comply with protected weight bearing and rehabilitation.

If the joint is already advanced, consider UKA or TKA according to the compartment pattern and standard arthroplasty indications.

When the balance is uncertain, explain both pathways and make a shared decision rather than promising a guaranteed result.

The point I emphasize to patients A meniscus root tear is not a diagnosis that automatically means surgery, but it is also not a tear I am comfortable dismissing. The decision is individualized because the consequences of leaving it untreated and the limitations of repair both matter.

References

1. Allaire R, Muriuki M, Gilbertson L, Harner CD. Biomechanical consequences of a tear of the posterior root of the medial meniscus. J Bone Joint Surg Am. 2008;90(9):1922-1931. PMID:18762653.

2. Krych AJ, Reardon PJ, Johnson NR, et al. Non-operative management of medial meniscus posterior horn root tears is associated with worsening arthritis and poor clinical outcome at 5-year follow-up. Knee Surg Sports Traumatol Arthrosc. 2017;25(2):383-389. doi:10.1007/s00167-016-4359-8.

3. Krych AJ, Lamba A, Wang AS, et al. Nonoperative Management of Degenerative Medial Meniscus Posterior Root Tears: Poor Outcomes at a Minimum 10-Year Follow-up. Am J Sports Med. 2023;51(10):2603-2607. doi:10.1177/03635465231185132.

4. Lee DR, Lu Y, Reinholz AK, et al. Root Repair Has Superior Radiological and Clinical Outcomes Than Partial Meniscectomy and Nonoperative Treatment in the Management of Meniscus Root Tears: A Systematic Review. Arthroscopy. 2025;41(2):390-417. doi:10.1016/j.arthro.2024.02.017.

5. Krivicich LM, Kunze KN, Parvaresh KC, et al. Comparison of Long-term Radiographic Outcomes and Rate and Time for Conversion to Total Knee Arthroplasty Between Repair and Meniscectomy for Medial Meniscus Posterior Root Tears: A Systematic Review and Meta-analysis. Am J Sports Med. 2022. PMID:34251898.

6. Jackson GR, et al. Outcomes After Isolated Medial Meniscus Posterior Root Repairs Using an Anatomic Transtibial Pullout Technique in Patients Older Than 60 Years: A Matched Cohort Study. Orthop J Sports Med. 2025. PMC11905030.

7. Husen M, Kennedy NI, Till S, et al. Benefits of Meniscal Repair in Selected Patients Aged 60 Years and Older. Orthop J Sports Med. 2022;10(9). doi:10.1177/23259671221117491.

8. Vosoughi F, Vahedi P, Nakhjiri MT, et al. High tibial osteotomy and concurrent medial meniscus root repair provides improved objective outcomes compared to high tibial osteotomy alone for knee osteoarthritis: A systematic review. Knee Surg Sports Traumatol Arthrosc. 2025;33(9):3361-3374. doi:10.1002/ksa.12796.