3D Printing Helps To Plan Limb Surgery on a Dog

3D Printing has proved to be useful for implants and prosthetics in animals. In fact, in 2018, 3D printing gave some animals a second chance. But now 3D printers can also be used for printing bone models that can help in pre-surgical planning. Let’s take the case of Buddy, a four-year-old castrated Havanese dog who presented a severe angular limb deformity (ALD).

Limb deformities in dogs are very difficult to plan and treat, and so far, this has been done by carrying out a preoperative analysis using radiographic orthogonal views. At this stage, size, hardware type, and osteotomy location is determined and then transferred to the animal. This procedure has resulted in satisfactory outcomes but having a 3D printed model of the animal’s limb can benefit pre-surgical planning.

The 3D printed limb model has the same scale as the dog’s actual limb, which allows surgeons to plan the surgical procedures in the most accurate way possible. This procedure provides several benefits such as lessening the time the animal is under anesthesia, lowering the risks associated with the size of the limb deformity, and decreasing the chances of any infection. This procedure can be expensive, but if we take into account said benefits, the cost of implementing 3D printed limb models can be justified, and surgeons can avoid any further revision surgery.

But surgeons are not the ones who decide to use 3D printed models. In the majority of cases, the owners of the animal take the decision of this alternative method. We are certain that during the last couple of years 3D printers have improved as have the materials used to replicate bones very closely. The procedure surgeons utilize for the pre-surgical planning allows them to cut and place implants on models, mimicking the real surgery and to study the final outcome.

Buddy had a right front antebrachial deformity that resulted in a significant physical disability. Surgeons performed orthogonal radiographs on Buddy’s limb to pinpoint the center of rotation angle, but it was difficult to determine it from the X-rays. Then, the surgeons performed a CT imaging. To generate the 3D views and to manipulate the limb further, a specific computer software was used. This software helped the surgeons to resolve the correction of angulation and rotation.

Finally, surgeons created the limb model using a 3D printer with a specially formulated resin that represents a real bone when cured. The model was performed with a closed-wedge osteotomy in oblique angle, resulting in an anatomically aligned radius and ulna. Then a jig was fabricated to be used intra-operatively. The implants were molded to the new configuration, and pre-placement of implants allowed surgeons to have an exact match preoperatively. Surgeons sterilized the implants and jig as to use them on Buddy intra-operatively.

Image via Veterinary Practice News

The final procedure was to place Buddy in ventral recumbency with the limb in a position that would allow surgeons to perform a cranial lateral incision over the osteotomy site. The technique they used was less invasive thanks to the 3D limb model that allowed surgeons to reduce the incision’s size significantly. The osteotomy was performed after the dissection and separation of the musculotendinous structures. Surgeons aligned the bone and placed the pre-contoured plate, lavaged and sutured the area in three layers, and Buddy was given a bivalve to be worn for two weeks. The pre-surgical planning with a 3D printed limb model saved surgeons time, and reduced the anesthetic time. Buddy’s morbidity was minimized thanks to this technique, providing a faster healing time of the limb.

3D printing has gained considerable success in many medical fields, including surgery. 3D printed models can help comprehend anatomical details that 2D imaging and 3D virtual models wouldn’t let you see. However, it will need additional manufacturing costs and additional time to access a 3D printer. Hopefully, these two main concerns can be improved in the future.

Source: Veterinary Practice News