Older mixed breed boxer dog with orthotic device running up a dog walk plank

Orthopedic Surgery

Dogs love to run, jump and play. An orthopedic injury can put that playful spirit on hold. Similar to the ACL in humans, the cranial cruciate ligament (CCL) is a tough band of tissue deep within the knee joint. If
the CCL ruptures or tears, the injury may cause your dog to limp or experience lameness. Damage to the cranial cruciate ligament requires expert repair to relieve pain and mitigate the development of arthritis!

At Sugar Hill Animal Hospital, Dr. Seibert specializes in a type of orthopedic surgery known as the Modified Maquet Procedure (MMP).

What is the Modified Maquet Procedure (MMP)?

MMP is a surgical repair of a ruptured cranial cruciate ligament, or CCL tear. These types of injuries cause the patient’s tibia ( shin bone ) to thrust forward when moving or even just bearing their own weight. CCL tears will not heal completely without surgical intervention.

MMP surgery is a minimally invasive procedure that can repair a torn or ruptured CCL in your dog’s knee joint. The surgery works by redirecting the impact of the large quadriceps ( thigh ) muscle to compensate for the injured cruciate ligament. The patellar tendon can then take over and act like a new CCL tendon.

Which Pets Can Receive MMP Surgery?

Failure of the cranial cruciate ligament is common in dogs. The Modified Maquet Procedure (MMP) can treat CCL injuries while also addressing pain and immobility.

CCL tears can be caused by a sudden injury. More often, they happen gradually over time, worsening with continued use. Some signs that your dog may have an injured CCL include:

  • Limping
  • Lameness in hind legs
  • Reluctance to jump or play
  • Favoring the opposite leg
  • Changes to their gait or the way they walk


There are a few cruciate ligament repair options for dogs, including TPLO (Tibial Plateau Leveling Osteotomy) and TTA (Tibial Tuberosity advancement).

TPLO surgery involves cutting into the tibia bone, rotating it and adjusting its position. Bone plates and screws are then used to hold the bone graft into place.

Although every patient is unique, there are a few reasons! Dr. Seibert may recommend MMP over TPLO or traditional cruciate repair:

  • MMP is minimally invasive
  • MMP only cuts the bone once instead of three times
  • MMP recovery time is significantly shorter, usually four to six weeks
  • MMP is usually more affordable, as it’s less time-intensive

What Does MMP Cruciate Ligament Surgery in Dogs Look Like?

The overall goal of MMP is to free the part of the tibia attached to the quadriceps muscle and redirect the force generated by these large muscles to compensate for the injured CCL. The tibia is the bone located between the knee and ankle. During MMP surgery, it’s moved forward to a 90-degree angle to the patellar tendon, allowing this tissue to take over and act in a similar way to the CCL.

The void is stabilized using an implant made from porous titanium OrthoFoam. This orthopedic implant promotes healing and accelerates bone growth. Capillaries can penetrate the OrthoFoam, reducing
patient convalescence and the pain your dog experiences post surgery. After four to six weeks, the implant fills with enough bone to stabilize the repair.

What to Expect After Treatment

To ensure your dog’s optimal healing after treatment, we will recommend a period of very limited activity. Although MMP tends to cause less discomfort than other procedures, the patient should not use the operated leg too quickly. Dr. Seibert will provide you with a set of discharge instructions detailing recovery restrictions.

Running, jumping and rough play should be avoided for at least six weeks post-surgery. You’ll also want to block off access to stairs. We recommend using a leash whenever your dog is outside for at least
two weeks. Following these recommendations will give the bone time to heal and reduce the risk of strain, stress fracture or implant failure.

After six weeks, X-rays should confirm that everything is healing as it should. By this time, your dog should be able to take walks for up to 30 minutes in grassy areas. After 12 weeks, your dog should be able to resume a normal level of activity.