CBLO Surgery Complications: Lightning Bolt’s Knee Injury and Surgery Disaster

When your dog sustains a serious injury it is always difficult to figure out what is the best treatment option.

When the recommended treatment means surgery, it gets even more challenging. A surgical intervention always comes with risks. Knee repair surgeries are successful for most dogs. However, potential surgical complications range from minor to severe and include:

  • anesthesia complications
  • surgical errors
  • swelling, bruising, and seromas at the incision
  • poor incision healing
  • infections
  • slow healing at the cut
  • meniscal tears
  • implant failure
  • bone fracture
CBLO Surgery Complications: Lightning Bolt's Knee Injury and Surgery Disaster

Lightning Bolt’s story

A few weeks ago, I happened on Jana’s article, Cora-based Leveling Osteotomy: My Two Cents on CBLO Repair, and commented regarding my dog’s poor outcomes following his 2013 CBLO. Jana very astutely asked if I was sure it was CBLO and not TPLO because CBLO is relatively new.

Although I was confused for a long time, it was definitely a CBLO.

Adopting Lightning Bolt

In the Summer of 2010, a stray yellow puppy came bolting toward me in a parking lot. We already had an older Lab with a neuromuscular and orthopedic disease. As a result, we hesitated to add this energetic little guy to our family. But, when nobody else claimed him, we had ourselves a new puppy. We named him Lightning Bolt. Friends and family joked that we would have better luck with his health because he was a mutt. Almost three years later, I sent those same individuals an email with the subject line “Lightning Is Striking Again.”

Lightning’s hip dysplasia

You see, as Lightning was approaching three years of age, he began having difficulty rising. I completely missed it despite my experience with an unsound dog, and a friend pointed it out to me.

Immediately, I made an appointment with Lightning’s general practice (GP) veterinarian. She took radiographs and referred us to a board-certified veterinary surgeon. The surgeon confirmed diagnoses of bilateral hip dysplasia and left medial patella luxation (MPL). In April 2013, Lightning had a right total hip replacement (THR) with plans for an eventual left THR/MPL surgery. His recovery from his right THR was uneventful.

Lightning’s bilateral cruciate tear and surgery

A few months later, we abandoned his left THR due to new onset of almost imperceptible lameness. It seemed on the right side. We received a referral to a different specialist at the same practice who focused on knees. During a rushed consult, he told us that

  • Lightning had bilateral cruciate tears
  • recommended surgery,
  • and happened to have an opening two days later

I understood that Lightning’s right cruciate tear (the first to be addressed) would be treated with a minimally invasive arthroscopic cruciate repair—my interpretation (and my error) like that used in humans. Immediately after surgery, it was clear that was not the case. Lightning was in severe pain, not to mention what the incision exposed when Lightning’s bandage fell off.


It was so early in the inception of CBLO that it would be years before I fully appreciated what transpired. Was CBLO a less invasive TPLO? I didn’t know, but something was off. I don’t recall ever seeing radiographs in the postoperative period, which might have helped clear up some of my confusion.

Lightning also had a skin stress reaction and infection. Two recheck visits with the orthopedist involved dropping Lightning off and picking him up later in the day.

I tried to articulate my concerns. However, I felt like I wasn’t being heard and kept being referred back to my GP to manage post-operative issues. Unfortunately, I didn’t advocate as I now know I should have. I attributed the communication problems to a bad fit. So I transitioned Lightning’s orthopedic care to our state’s College of Veterinary Medicine.

For much of 2014, the university trainees and clinicians focused on Lightning’s left side. Despite the university being the purported birthplace of CBLO and Lightning having a concomitant left cruciate tear and MPL (i.e., one of the stated indications for CBLO), the team performed TPLO and MPL surgeries (trochlear groove recession followed by tibial tuberosity transposition). We were aghast when we saw the x-rays [Figure 1], but we trusted we were doing right by our boy. After those surgeries, we decided to take a break because the operations took a toll on Lightning (and us).

CBLO Surgery Complications: Lightning Bolt's Knee Injury and Surgery Disaster - radiographs
Figure 1. Serial left lateral stifle radiographs (TPLO + MPL surgery)

Worsening pain

In 2015, Lightning had worsening pain and difficulty walking with continued right leg retraction. It looked as though stepping on something painful or stung (this had been problematic since his 2013 right cruciate surgery). He also kept his right leg straight when lying down. We went to his GP often. Even though it seemed his problems were right-sided, we reasoned that his left (unaddressed) hip dysplasia and/or Frankenstein-like left knee and/or the weather must have contributed. So we treated him with increasing pain medications.

Acute severe lameness

In early 2016, Lightning became acutely and severely lame and apparently painful on his right side. My GP took full-body radiographs to cover all the bases. She was able to get a same-day review by a radiologist. I will never forget what she showed me.

She, the radiologist, and I were all perplexed by what we saw on February 5, 2016 [Figure 2]. Because we needed an explanation, Lightning, my husband, and I went back to the original surgeon. The interaction continued to feel off, so we sought a second opinion. That surgeon believed Lightning might have a late meniscal tear (LMT),. This complication seemed more common after CBLO due to its persistent instability.

Surgery indeed confirmed an LMT. However, Lightning’s 2013 early partial cruciate tear also progressed to a complete cruciate tear despite CBLO. Both tears were cleaned out, and most of the implants in his right knee were removed. Much to my dismay, the protruding compression screw was left, because the risk of explanting was felt to be high. (I have since learned that it can be technically challenging and cause morbidity to remove a compression screw.)

CBLO Surgery Complications: Lightning Bolt's Knee Injury and Surgery Disaster - radiographs
Figure 2. Serial right lateral stifle radiographs (CBLO)

We completed a long course of physical therapy with a board-certified sports medicine and rehabilitation specialist in hopes of helping Lightning. Still, his problems persisted (I believe due to the bone-cutting screw tip remaining in his soft tissue). He was eventually taking more than 20 pain pills per day without relief. So finally, after consulting with a wonderful home hospice veterinarian, we humanely released Lightning at just six years of age, in our backyard, on his favorite chaise.

Cora-based Leveling Osteotomy (CBLO) lesson

I thrust myself into learning about CBLO, poring over details as they became available. An initial case series had been published after Lightning’s surgery, so I at least had one source of peer-reviewed information. In 2016 (shortly after we discovered that Lightning had been used for a “TPLO Study” but treated with CBLO), a second case series followed, and a third in early 2018.

All were retrospective cases treated by the same group who devised CBLO and seemed to have many redundant patients. While the papers reported that the CBLOs were performed between 2009 and 2013, there was no mention of where the patients came from. And all outcomes were subjective.

In fact, a stated limitation in the second paper was the lack of objective measures such as:

  • force plate
  • or kinematic gait analysis because the equipment was not available.

Lightning had force plate and video assessments, but he didn’t fit the selection criteria for the case series and so was not (to my knowledge) included in any of the reports. A book chapter recently spoke to discomfort from a too-long compression screw.

In closing

I will probably always have many questions about CBLO. However, I have gained a fair amount of knowledge, including:

  • the rationale for its use
  • modifications to improve outcomes,
  • and more

So far as I can tell, CBLO came into use principally in private practice patients in 2009. At that time, there were no prospective controlled clinical trials and none have been completed in the 12 years since.

Some have defended this approach by referring to TPLO’s introduction. I believe we have advanced beyond the 1980s, but of course, I am biased. Regrettably, I had no idea my dog could be used as a study subject without my express consent. Many years have passed since Lightning’s CBLO. He was one of the early patients who had complications that are now becoming more widely recognized. I hope his case and those like his help contribute to better outcomes for other dogs.

Related articles:
Cora-based Leveling Osteotomy: My Two Cents on CBLO Repair

Further reading:
CORA Based Levelling Osteotomy (CBLO)

  1. I’m so sorry to learn that you and Lightening went through this journey without consent. That’s alarming. I hope by sharing your story other pet parents will be better informed about their options and what they are comfortable with. Thanks for sharing.

  2. Oh my goodness, what a terrible journey you went on with Lightening! You’ve become extremely educated on the subject out of necessity. I agree with you, I hope it helps others in the same situation as Lightening. What a wonderful home Lightening had with you and your family. Thank you for so bravely sharing your’s and Lightening’s story.

Share your thoughts