If you’re reading our blog, you are probably familiar with “Daffodil on Wheels,” the plucky and awe-inspiring two-legged Chihuahua who uses an OrthoPets Wheelie Vest. Daffodil has her own Facebook page and many friends and fans who love to see videos of her hiking, popping wheelies and generally kicking butt in (and out of!) her wheels. While Daffodil took to her wheels with a combination of sheer talent and work doing rehabilitation with her owner, not every dog is such a natural when they first receive their OrthoPets Wheelie Vests.
Meet Mocha, a 9-year old, 12 pound Chihuahua mix. Mocha was born with agenesis of her left forelimb. She also had two different IVDD (slipped disc) events in her history that were causing her pain and discomfort. Her owners found OrthoPets when they were searching for ways to help her avoid future back injuries and give her easier and more comfortable mobility.
The two options that Rachel, Mocha’s OrthoPets Case Manager, presented to Mocha’s owners were either a hoppy/wheelie vest or a carpal orthosis to support Mocha’s “good” forelimb with a possible combination of both in the future. Mocha was not a candidate for a prosthetic on her residual limb since to build a functional forelimb prosthetic, the patient needs at least 40-50% of the radius and ulna remaining. Ultimately, Mocha’s owners, veterinarian, and Rachel opted for the Wheelie Vest with an option to add a carpal support later if Mocha started to show any signs that additional carpal support was necessary.
The device that OrthoPets designed for Mocha is a fairly standard Wheelie Vest, though it was designed with the central axel a little bit to the left to accommodate Mocha’s habit of adducting her right forelimb in motion. Mocha’s device also came with an integrated D-ring leash attachment at the front in order to help teach Mocha how to turn her wheels, which can be one of the more challenging aspects for patients learning to use a Wheelie Vest.
When Mocha first got her vest, she was clearly nervous about it. Her owners worked hard with her to associate it with positive events (like treats) and in the beginning they started by just putting Mocha in it and letting her have treats for sitting calmly in the Wheelie Vest instead of trying to wriggle out. Once Mocha got comfortable with lying quietly in the device, she was able to move on to short sessions walking straight ahead on a smooth, easy surface in a controlled environment.
Eventually, Mocha started gaining confidence in her wheels and going faster, as well as learning to turn herself to avoid obstacles. Once she started picking up speed (literally and figuratively!) it became clear that her right forelimb was sometimes hitting the axel of the cart when she moved any faster than a walk. It was determined that it was partially a result of Mocha’s habitual adducting of that limb to bear weight on from before she had her wheels. Mocha’s device was sent back to OrthoPets for an adjustment to move the axel forward giving her more space for that front paw. Even with the adjustment, it was important that Mocha continued rehabilitation exercises to help learn appropriate posture and more even weight distribution with her trunk.
Mocha’s device came back to OrthoPets for one more adjustment to strengthen one of the bars of her device. Once the adjustment was completed and the Wheelie Vest was sent back home, Mocha’s owners reported that Mocha was excited just to see them come out of the box! Her owners also report that since using her wheels regularly, not only is Mocha more mobile, but she has less overall pain to the point that she hasn’t needed any pain medication for her legs or back. Wow!
Great job Mocha and family! You’re an inspirational little pup and we love seeing your success with your wheels!
Our American Mastiff, Duke, suffered a serious spinal cord injury that left him paralyzed initially on his left side. As he recovered he began to overuse his right carpus (wrist) and began to injure it. Our vet recommended a custom orthotic from OrthoPets. From our initial contact with them, they were extremely helpful, knowledgeable, and professional. They truly cared about Duke’s situation. Martin and his team of specialists thoroughly explained our options and developed a plan, and an Orthotic, that would allow Duke maximum use of his leg. OrthoPets fantastic staff and customer service are some of the best I have seen, and have worked closely with us through numerous fittings and adjustments. Today Duke is doing great and is able to walk, run at a full sprint, and enjoy a great life thanks to OrthoPets!
OrthoPets Case Study: Shia
Shia is a 6-year-old female spayed mixed breed dog who lives in North Carolina. She presented in January 2017 with a partially torn CCL in her right hind leg. Shia’s owner wanted to pursue a conservative course of rehabilitation with an orthotic instead of surgery. Shia’s case was relatively straightforward, with a good possibility for a “curative outcome” which means we have provided a stable environment to allow the body to lay down functional scar tissue. After reviewing her media, additional componentry was not deemed necessary for suspension or control. However, due to her thin fur and prominent malleoli, it was decided that additional modifications would be made to the device to alleviate additional pressure on those prominent anatomical landmarks. Relief channels were ground into the foam of the distal tarsus lateral, medial and cranial. Then, a thin black, non-friction material called “glide” was added to this area.
Shia received her device in mid-January and used it in conjunction with a formal rehab program at Vanguard Veterinary Hospital in West End, North Carolina. Her rehab program included use of a gait analysis mat, so we wanted to share some of her GLS numbers. Initially, her owner was concerned because in her first week with the device, Shia actually showed more weight bearing out of the device than in it. She had a GLS score on her right hind of 77 with the device and 83 without it (higher number shows more weight bearing). This favoring of the leg can be common upon first receiving a device; patients do not yet trust the device to support them and experience muscle fatigue from starting to use muscles again that have atrophied due to the injury.
Shia’s orthotic did return to OrthoPets for an adjustment about one month into her time in her device because she developed an irritation at her achilles due to her distal migration of the device. The adjustment involved grinding the top of the shell to decrease the overall height as her flank/groin was pushing the device down and adding non-friction glide material to the achilles strap to help alleviate the rubbing. By this time, thanks also to her fantastic rehab work with Vanguard, she was at a GLS score of 100 on her right hind both with and without the brace, so her owner felt comfortable letting her go without the brace for a few days for the adjustments to be completed.
Now, not even four months after receiving her device, Shia is completely weight-bearing again and uses her orthotic just as a sports brace to help prevent re-injuring the ligament when she does high-impact activities like playing at the beach with her owner!
Meet Morgan! Morgan is a shepherd mix pup who received her below tarsus prosthetic device through Dr. Kern at our fantastic Michigan Partner Clinic, Pawsitive Steps Rehabilitation. Morgan’s initial consult was at only 10 weeks of age, not long after she was adopted by a pair of veterinarians. Morgan was born without her distal left hind limb, below her tarsus. She would to try to walk on her stump when moving slowly, but would hold it up and hop on three legs when she wanted to go faster. Sometimes, she had a hard time getting traction with her stump, which was challenging for her. She would also to extend the tarsus/hock joint of that limb very straight, possibly in an effort to “reach” for the ground with the stump.
Everyone agreed that Morgan would be a great candidate for a prosthesis, but because of her young age and likelihood of needing multiple devices as she outgrew them, her owners opted to wait to start the prosthetic process until Morgan was closer to full grown. In the meantime, Morgan did a lot of rehabilitation at Pawsitive Steps to work on improving her core strength, balance and especially focused on flexing the tarsal joint of her residual limb. It was also very important to get her comfortable with that limb being handled to prepare her for donning and doffing of the device.
When Morgan was close to full grown, Dr. Kern did her fiberglass impression and measurements for her prosthetic device. Because of the amount of limb remaining, Morgan was borderline between making a prosthetic with a non-articulating tarsus (no motion) and an articulating one (motion allowed). Since Morgan is young and preserving as much range of motion in her tarsal joint as possible was priority, Dr. Kern and Silver (Morgan’s OrthoPets Case Manager) decided on the articulating version, with motion limiting straps available in case Morgan did not handle the articulation well.
Morgan received her device in August of 2016. Her device not only helps protect her stump and gives her good traction, but makes up the limb length discrepancy she has so that her hips can be level and her spine can stay neutral, which is very important for long-term health and comfort. Slow acclimation to the device is important to ensure the patient is using the device properly. Otherwise, they may form “bad habits” such as lifting their prosthetic limb during faster gaits, improper sitting, etc. Rehabilitation and supervised, structured, slow and steady work upon receipt of a device is important so that patients can learn good habits and become accustomed to using the device as if their prosthetic limb had been there the entire time and eventually they can tear around and play.
Great job, Morgan and family! We love your pirate style!
Bianca has been doing exceptionally well! Here is a video of Bianca 11 days after her initial fitting: Bianca: 11 Days Post Initial Prosthetic Fitting
Gibson is a 5-year-old MC Border Collie that lives in Mexico. His veterinarian is Dr. Gabriel Ramirez who has a long working relationship with OrthoPets. Dr. Ramirez frequently sees cases that have had complications elsewhere and is known to “think outside of the box” with the goal to his patients to gain their mobility back as quickly as possible. In Gibson’s case, he had a pancarpal arthrodesis. Unfortunately, the post-operative bandage was placed too tightly and caused tissue necrosis. The medical team tried to save the limb but eventually the “only” established option for him was a full-limb amputation. However, since the affected area was distal on the limb, the owner elected a sub-total amputation and prosthetic.
OrthoPets is currently gathering retrospective and prospective data on canine prosthetics, however, based on our current experience a few things are important when considering a prosthetic device: Prosthetic candidates should be amenable to handling of the residual limb and a long enough limb to allow appropriate suspension of the device and proprioception to properly use the device in a functional manner is necessary.
The combination of these two factors will translate into the functionality of the device and ultimately serve as a predictor for the success of the case. The total length of residuum is currently unknown, and it varies depending on the anatomy of the remaining limb. For example, we have some cases that show appropriate suspension with a mid-radius amputation while others don’t have prominent enough humeral epicondyles to allow successful suspension. In general, the more distal the better the chances to have a successful outcome. As such, Gibson is a perfect case for this treatment.
Regarding the surgical approach to a sub-total amputation with the goal of utilizing a prosthesis, it is important to consider the following:
- Skin suture line location to avoid scar tissue formation on the weight bearing surface of the limb
- Remaining soft tissue placement to encourage comfortable weight bearing
- Identification of nerves to avoid placement over the residuum
Gibson’s amputation was performed so that the accessory carpal bone remained which created a bulbous distal end aiding with the suspension. The device was fabricated with a removable liner for replacements to be sent as needed rather than requiring the device to be sent to us. A traditional style prosthesis has a “fixed” liner that is connected to the shell requiring the entire device and additional steps to replace or change the liner. The removable liner approach allows us to replace, duplicate and adjust the foam liner without needing the entire device.
Gibson was fit with his prosthesis and immediately took very well to it! So far, Gibson’s device has not needed any adjustments aside from tread replacement which can easily be done by his owner. The entire team at OrthoPets as well as his medical team was pleased with the fit of the device and how quickly Gibson adapted to his old activities such as playing with a Frisbee. Gibson will need regular rechecks to ensure that the device is not only fitting well but that the device is still providing appropriate function to his affected limb.
For additional information: Colorado State University is conducting an ongoing study evaluating partial amputation in dogs. Read more here.
Bertocci, Gina E., and Nathan P. Brown, “Biomechanics of an orthosis-managed cranial cruciate ligament-deficient canine stifle joint predicted by use of a computer model.” American Journal of Veterinary Research 78.1 (2017): 27-35.
To evaluate effects of an orthosis on biomechanics of a cranial cruciate ligament (CrCL)–deficient canine stifle joint by use of a 3-D quasistatic rigid-body pelvic limb computer model simulating the stance phase of gait and to investigate influences of orthosis hinge stiffness (durometer).
A previously developed computer simulation model for a healthy 33-kg 5-year-old neutered Golden Retriever.
A custom stifle joint orthosis was implemented in the CrCL-deficient pelvic limb computer simulation model. Ligament loads, relative tibial translation, and relative tibial rotation in the orthosis-stabilized stifle joint (baseline scenario; high-durometer hinge) were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. Sensitivity analysis was conducted to evaluate the influence of orthosis hinge stiffness on model outcome measures.
The orthosis decreased loads placed on the caudal cruciate and lateral collateral ligaments and increased load placed on the medial collateral ligament, compared with loads for the CrCL-intact stifle joint. Ligament loads were decreased in the orthosis-managed CrCL-deficient stifle joint, compared with loads for the CrCL-deficient stifle joint. Relative tibial translation and rotation decreased but were not eliminated after orthosis management. Increased orthosis hinge stiffness reduced tibial translation and rotation, whereas decreased hinge stiffness increased internal tibial rotation, compared with values for the baseline scenario.
CONCLUSIONS AND CLINICAL RELEVANCE
Stifle joint biomechanics were improved following orthosis implementation, compared with biomechanics of the CrCL-deficient stifle joint. Orthosis hinge stiffness influenced stifle joint biomechanics. An orthosis may be a viable option to stabilize a CrCL-deficient canine stifle joint.
- Orthoses for CCLD have been reported. Their efficacy is dependent on device, owner, care-provider (adjustment, fitting of device and rehabilitation) and animal factors.
- Orthosis allows limited functional movement (rather than complete immobilization) according to 4-point force application system used in humans with ACL-tears with the following cranial constraints (quads, tibial tuberosity, distal tibia) and caudal constraints (semimembranosus and semitendinosus, gastrocnemius muscles and calcanean tendon)
- However, stabilizing effect of canine stifle orthosis has not been investigated
Materials and Methods:
- Previously developed and validated computer model (3-D quasi-static based on 33kg Golden Retriever) utilized to test Orthopets CCLD-orthosis (with 2 Tamarack hinges at stifle) that was molded specifically for the dog that the computer model was based on
- A 3-D scan of the orthosis was then performed to import the orthosis into the previously developed stifle model and loads on the ligaments (caudal CL, MCL, LCL) and tibial rotation and translation (drawer) through stance phase were compared between CrCL-intact, CrCL-deficient and CrCl-intact and -deficient with Orthopets orthosis
- Different hinge stiffness (Tamarack 740-L [high] and Vet-L-65 [low stiffness]) were also evaluated
- CrCL-deficient stifle compared to orthosis-managed CrCL-deficient stifle showed reduced tibial translation (91%) and rotation (61%)
- CrCL-intact stifle compared to orthosis (with CrCL-intact stifle) showed significantly different peak loads (i.e. orthosis changes the loads compared to an intact stifle):
- Loads on the caudal cruciate (38%) and lateral collateral ligament (53%) were reduced while MCL increased (50%)
- CrCL-deficient stifle compared to orthosis-managed CrCL-deficient stifle showed significantly decreased peak loads for all ligaments tested:
- Caudal cruciate (90%), lateral collateral ligament (93%) and MCL (59%)
- Hinge stiffness significantly impacted tibial rotation (decreasing rotation with increasing hinge stiffness)
- Stifle orthosis for CrCL-deficient stifle reduced translational instability by 90% in this computer-model
- The tested device (Orthopets stifle orthosis) significantly improved biomechanical stifle stability in the stifle with cranial cruciate ligament deficiency
- Stifle orthosis for CrCL-deficient stifle decreased loads on the collateral ligaments and caudal cruciate ligaments in this computer-model
- The tested device (Orthopets stifle orthosis) may prevent subsequent injury to ligamentous structures
- The tested design appears to reduce loading of the lateral collateral ligament to a greater degree than medial collateral ligament
- Hinge stiffness had the greatest impact on tibial rotation
- If greater control of internal tibial rotation is required (such as pivot-shift cases) a stiffer hinge should be considered
- While computer models have been previously validated and appear highly predictive some variables are introduced when using a ‘real’ patient that may change these results (such as the cuffs were ‘modeled’ as a straight line, the foam may compress over time etc.) – in other words the result of this model are likely superior to what can be accomplished in a clinical patient
- Modeling limited because it was based on one patient at one time-point only
Hello LiLen and all of the wonderful OrthoPets team,
I spoke to Lilen this morning about my dog Levi who two years ago was suffering from a cruciate tear in his left rear leg. OrthoPets fitted him with a stifle brace and the whole process was so positive. At that time he was just 14 and I was uncertain about his ability to bounce back from such an injury at his age. I am very proud to say that this spring he will turn 17 years old!!! He no longer needs his OrthoPets stifle brace but he took to wearing it almost immediately.
The stifle brace gave his leg the stability to heal while keeping him active – this to me is the genius of these braces. At his age mobility is EVERYTHING!!!
When he was 12 he tore his right leg cruciate and I opted to have surgery. It took a full 6 months for him to be able to walk and move freely again and consequently he lost much of his muscle tone and mobility. While I don’t regret my decision (and recognize that surgery is the best course of action in some cases) the process was so arduous and tentative. It was so amazing to have the option to use the OrthoPets brace and be a lot more proactive in the healing process – and to be able to keep him moving!
I am so grateful everyday that somehow I connected with OrthoPets. Without their help, I would not be enjoying each and everyday with my happy and healthy pup! Thank you a million times over!!!
Courtney and Levi
OrthoPets Case Study: Bailey
Bailey is a 6-year-old MC Labrador that is currently a patient of one of our Partner Clinics in San Francisco. Dr. Illana Strubel, owner of A Well Adjusted Pet, has come to OrthoPets and studied the use of our orthotic and prosthetic devices to use with her patients.
Bailey presented in September 2016 with a history of toe touching weight-bearing and non-weight bearing lameness intermittently over the previous 4 months. The radiographs showed inflammation and DJD changes in the left stifle with mild changes in the right stifle as well. He had a medial buttress palpable bilaterally with minimal to no cranial drawer or tibial thrust palpable on awake evaluation. He did show adequate range of motion, was able to sit and lie squarely. His measurements showed a 1-2 cm muscle mass discrepancy between the left and right thighs on girth measurements. The radiographic and physical exam conclusion was that they suspected a chronic partial to complete cranial cruciate ligament tear, +/- meniscal injury, with secondary degenerative change and crus muscle disuse atrophy for the left stifle. The conclusion for the right stifle was suspicion for equivocal increase of right stifle joint fluid volume with minimal tibial osteophyte; concern for possible early/mild partial cranial cruciate ligament tear and +/- meniscal injury.
The owners’ goal was to avoid surgery on the left pelvic limb and increase Bailey’s comfort. Due to his discomfort, they had to decrease his walks, which led to a 10-pound weight gain. When OrthoPets received Bailey’s measurements, fiberglass impression and media, we were able to analyze his gait to determine the most appropriate orthotic design for him. In some cases, when a pet has non-prominent malleoli or an extended terminal stance tarsal angle, a tarsal cuff component is required for suspension of the orthosis because standard use of the tarsal anatomy will not be sufficient.
Bailey was fit with his stifle orthosis and has been doing very well. He is continuing his rehabilitation with Dr. Strubel. She reports that he is building back muscle mass and has been able to go on walks with the dog walker to get his weight back on track. His owners are very pleased with his progress, and best of all Bailey is happy!
OrthoPets Case Study: Alley
In October 2014, Alley was diagnosed with a grade II medially luxating patella and suspected cranial cruciate disease. Since the cranial cruciate ligament also controls internal rotation of the stifle, CCLD can result in MPL by allowing excessive internal rotation and cranial displacement of the tibia. Both of these contribute to the patella luxating medially. Alley was partial non-weight bearing for almost two weeks and unfortunately was also diagnosed with concurrent transitional cell carcinoma in her bladder. She had been a very active dog until then, however, due to the co-morbidities, surgery was not an option for the owner. They were looking for a palliative solution to keep Alley comfortable until her quality of life was no longer acceptable.
While the orthosis is able to provide global support to the stifle, we generally only recommend orthoses for the treatment of low grade (I-II) patellar luxations. With the addition of a tarsal cuff, we are able control rotation of the affected leg which may assist with controlling the luxation (by providing resistance to internal rotation that is usually controlled by the cranial cruciate ligament). However, with grade III-IV luxation and in dogs without cruciate disease, the orthosis cannot provide enough external rotation of the tibia to allow for appropriate tracking of the patella.
In March 2016, Alley suffered a similar problem on her contralateral leg. Since Alley had done well with the original stifle orthosis, the owners decided to pursue it again. Alley received a stifle orthosis with a tarsal cuff for her contralateral leg. She has been doing well with her new orthosis and has been able to return to her normal activities again.