MRIT Surgery (Lateral Suture / Modified Retinacular Imbrication Technique)

A trusted, less invasive option for stabilizing a torn cruciate ligament in smaller and less active dogs.

The Modified Retinacular Imbrication Technique (MRIT) — also called lateral suture stabilization or extracapsular repair — is one of the most established surgical options for treating a torn cranial cruciate ligament (CCL) in dogs. It has been used successfully for decades and remains an excellent choice for many patients, particularly smaller and less active dogs.

What Is MRIT?

MRIT stabilizes the knee (stifle) joint from outside the joint capsule rather than by cutting and repositioning bone, as with TPLO. A strong synthetic suture is placed to mimic the job of the torn cruciate ligament, holding the tibia and femur in proper alignment while scar tissue forms around the joint to provide long-term stability.

Is MRIT Right for Your Dog?

MRIT tends to work best for dogs under roughly 40–50 lbs and those with lower activity levels. Larger, more athletic dogs are often better candidates for TPLO, which more directly addresses the biomechanical forces at play in bigger joints. During your pet’s consultation, we’ll evaluate size, activity level, joint conformation, and overall health to recommend the procedure most likely to give your dog the best long-term outcome.

How the Procedure Works

Through a small incision at the outside of the knee, a strong suture material is anchored behind the joint and secured to the front of the tibia, recreating the stabilizing function of the CCL. Unlike TPLO or TTA, no bone is cut, which typically means a shorter surgical time and a lower up-front cost.

Recovery After MRIT

Most dogs begin light weight-bearing on the leg within the first couple of weeks, with a full return to normal activity generally expected around 8–12 weeks. Strict activity restriction in the first several weeks is essential — leash walks only, no jumping, running, or stairs — to give the suture and surrounding tissue time to stabilize the joint. Pain management and, in many cases, physical rehabilitation are part of a full recovery plan.

MRIT vs. TPLO

Both procedures aim to eliminate the instability caused by a torn CCL, but they take different approaches. MRIT is an extracapsular (outside-the-joint) repair using suture material, while TPLO is a bone-cutting (osteotomy) procedure that changes the geometry of the tibial plateau. TPLO is generally considered the gold standard for large or highly active dogs, while MRIT remains a well-supported, lower-cost option for smaller or less active patients. We’ll walk you through the tradeoffs for your specific dog.

Why Choose Our Team

Our surgical team offers in-house CT imaging for precise pre-surgical planning, same-week consultations, and financing options through CareCredit and ScratchPay. We also treat the full spectrum of orthopedic conditions, so if MRIT isn’t the ideal fit for your dog, we can walk you through other cruciate ligament repair options or refer you to our broader orthopedic surgery services.

Schedule a Consultation

If your dog is limping, favoring a hind leg, or has been diagnosed with a torn or partially torn cruciate ligament, call us today to schedule a consultation and find out whether MRIT is the right path forward.