Our QLF™ Method

Read on to learn more about the technique that Dr. Murtha has been perfecting for decades as a viable alternative procedure.

You likely found us because you were searching for an alternative surgery after your dog’s diagnosis of a torn CCL.

Our QLF™ surgical procedure is based on proven scientific principles and our typical clients are educated forward-thinking individuals in the Boston area often in professions such as the human medical field (physicians, nurses, chiropractors, etc.) and engineering. We’re glad you’re here and excited to share with you our method that we hope will revolutionize how CCL (ACL) tears in dogs are treated as a fast-emerging viable alternative to TPLO and TTA (metal implant) surgeries.

Tearing of the cranial cruciate ligament (CCL) or commonly referred to as the ACL (the human version) is the most common orthopedic injury in dogs. The CCL (ACL) is one of the main stabilizing structures in the stifle (knee) joint. Our Quadri-Lateral Fabella™ surgical repair procedure, abbreviated to QLF™ (also referred to as the Multi-Filament Load Sharing™ surgical method or MFLS™ surgical method) and performed at the Canine Cruciate Center of New England (located at North Andover Haverhill Animal Hospital in North Andover, MA), is a proprietary procedure that provides exceptional stabilization of the canine stifle joint and consistently outstanding results that enable our patients to be highly functional and resume an active lifestyle.

The development of our QLF™ surgical procedure.

When Dr. Murtha graduated from Tufts University School of Veterinary Medicine in 1985 there simply was no surgical procedure that reliably stabilized the stifle of larger dogs (there was no TPLO surgery and would not be for another 10 years or so). There was only “Lateral Suture” surgery which worked well for smaller dogs (less than 30 lbs) and still does. In his research, Dr. Murtha read an article about the 1967 collapse of the Silver Bridge in Ohio. This article was essentially a forensic analysis of why this bridge, built in 1928, ultimately failed. The article discussed the lessons learned in terms of the design and engineering of single cable bridges vs. multi-cable bridges built during the same time period. The multi-cable bridges built in that time period are still standing strong because they were designed to distribute and share the load among multiple cables instead of just one, and these multi-cable bridges were built with materials of a tensile strength that was twice the maximum anticipated load the bridge would carry.

This article served as the inspiration for Dr. Murtha to develop a surgical procedure employing this same fundamental principle of physics … load sharing and distribution. Dr. Murtha’s new load-sharing surgical procedure had immediate early successes and over the next 15 or 20 years (the developmental stage) he continued trying different materials and methods evolving and advancing the procedure. Over the last 15- or 20 years Dr. Murtha has refined the procedure to consistently provide outstanding results for patients of all sizes. Our survey results evidence that at just 1-year post-op, clients report that 93% of patients are doing “well”, and 2 out of 3 of our patients are doing what the client feels is “outstanding”.

  • Our QLF™ surgery is simply a more natural approach to treating canine CCL injuries. QLF™ surgery is simply a more natural approach and works because rather than attempting to redesign the anatomy of the canine stifle and reengineer the biomechanics of the joint (as TPLO and TTA surgeries attempt to do), QLF™ surgery simply re-stabilizes and reinforces what mother nature created in the first place… an already proven and outstanding anatomical “design”.

  • The anatomy of the canine stifle is virtually identical to the human knee, and in fact, the anatomy of this joint is pretty much identical and pervasive throughout all mammals. This anatomy and its biomechanics have withstood the test of time, surviving and perpetuating over millions of years of evolution. Why is that… Because it works! Who among us would choose a human redesign of this anatomy over mother nature’s tested and proven design that has survived and thrived for millions of years?

The bio-synthetic union just gets stronger and stronger over time. Our QLF™ surgery re-stabilizes and reinforces mother nature’s anatomy and in essence mother nature returns the favor by reinforcing our implanted synthetic ligaments over time.

In this way… we know from cadaver studies (studies on deceased patients who’ve previously had nylon implants) when pathologists look under a microscope, they see that these nylon implants have become encased in scar tissue… much like if you have a splinter or foreign body in your finger, your immune system tries to wall it off with scar tissue. Scar tissue is made of collagen… as are ligaments and tendons (slightly different forms of collagen… but it’s all collagen).

So, while not by original design or intent, our implants serve as the framework or infrastructure on which the body’s immune system essentially builds a new outer collagen “ligament” by encasing the multiple synthetic nylon filaments in collagen. From day, 1 our QLF™ repair itself (multiple synthetic nylon ligaments) is many times (typically 8 to 10 times) as strong as the load (weight and force) that will come to bear on the dog’s stifle joint, but with mother nature’s help, this bio-synthetic union just gets stronger and stronger over time. It is for this reason that we simply just don’t see patients return with a disrupted or failed repair after the initial healing period (typically 6 months).

Faster patient recovery time from our QLF™ surgery has a “sparing effect” on the opposite limb CCL tear rate.

Our QLF™ surgery has a very low opposite limb CCL tear rate because by the time we are removing the skin staples at 2 weeks post-op, the majority of our patients are beginning to use the repaired limb with some authority, and the remaining patients typically follow suit soon thereafter. Most of our clients tell us the biggest problem they have after surgery is “keeping the reigns in” as the patient feels so good so fast they want to do more than is allowed. There is substantial healing that needs to happen over the first 8 weeks post-op, so carefully following the post-op rehabilitation protocol is essential.

We see fewer patients tearing their opposite limb CCL (ACL). In fact, our opposite limb tear rate is just 16% overall. Dr. Murtha firmly believes this is because the recovering patient is not forced to carry most if not all of their body weight on their opposite (good) hind limb for an extended period of time. The faster and easier postoperative recovery has a “sparing effect” on the opposite hind limb and, thus, reduces the chances of another tear and having to do a second CCL (ACL) surgery.

Strength in numbers.

The science behind our QLF™ surgery that calls for distributing or sharing the load among multiple filaments placed strategically to provide stability to the stifle joint throughout its entire range of motion also provides a built-in safeguard against the failure of the surgical procedure as a whole.  By not relying on a single filament to carry the entire load (hence a single point of failure should the filament slacken, loosen, or break) multifilament load sharing requires multiple points of structural failure before complete failure of the surgical repair is ever a possibility.

Canine Cruciate Center of New England

1 week 17 hours ago

Big smile from Lucy on her graduation day! Well done! 🎓

Canine Cruciate Center of New England

1 week 1 day ago

Excellent work, Maxee! Congrats on a well-earned graduation! 🎓

Canine Cruciate Center of New England

1 week 2 days ago

A big congratulations to Clover on graduating! 🎓

Canine Cruciate Center of New England

2 weeks 17 hours ago

Maeve is doing so great at 10 years old and we are all thrilled to see her graduate! 🎓

Canine Cruciate Center of New England

2 weeks 2 days ago

Angel gave us a big smile for her graduation photo! Well done 🎓

Canine Cruciate Center of New England

2 weeks 3 days ago

Our 3-year-old bilateral patient, Luna, is now a graduate! 🎓

Canine Cruciate Center of New England

3 weeks 16 hours ago

Sweet Maple is looking good at her 8-week postop recheck!

Canine Cruciate Center of New England

3 weeks 2 days ago

Sweet Mei posing with her diploma and graduation cap 🎓💕

Canine Cruciate Center of New England

4 weeks 17 hours ago

Congratulations, Stella, on all your hard work and becoming a graduate! 🎓

Canine Cruciate Center of New England

1 month 3 weeks ago

Maple keeping her cone on like a good girl! So critical to follow the post-op care to ensure the best recovery 💙

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