FONT study explores one-cut option for dogs with CrCL disease and MPL

A newly published Journal of Small Animal Practice paper is putting a spotlight on a possible new way to manage one of small animal orthopedics' more complicated stifle combinations: concurrent cranial cruciate ligament disease and medial patellar luxation. The study describes the Fulkerson-based oblique novel technique, or FONT, which uses a single oblique tibial tuberosity osteotomy with a standard tibial tuberosity advancement cage to create both cranial advancement and lateralization of the tibial tuberosity. The paper was published online March 18, 2026, and appears in the August 2026 issue of JSAP. (pubmed.ncbi.nlm.nih.gov)

That clinical problem has a long surgical history. Dogs with concurrent CrCL disease and MPL often need correction of both instability and extensor mechanism malalignment, and the literature reflects a range of approaches, including extracapsular stabilization with tibial tuberosity transposition, tibial tuberosity transposition-advancement, combined TPLO and TTT, and modified TPLO-based strategies. Review and continuing education sources describe these cases as common in practice, especially in smaller dogs, and cite the need to tailor surgery to the underlying deformities rather than rely on a one-size-fits-all repair. (todaysveterinarypractice.com)

In the new JSAP study, investigators evaluated FONT through theoretical calculations, 3D computer simulation, and cadaver testing rather than live-patient outcomes. Four osteotomy angles were modeled: 0, 25, 30, and 35 degrees. At 30 degrees, the model predicted 50.0% lateralization and 86.7% advancement; at 35 degrees, lateralization increased to 57.3% while advancement dropped to 82.0%. In 14 cadaveric tibiae, the mean achieved osteotomy angle was 32.27 degrees, significantly different from the 30-degree target. Across cage sizes of 3, 6, 9, and 12 mm, lateral translation exceeded the target and cranial translation fell short, suggesting freehand execution may not reliably reproduce the planned correction. (orthovetsupersite.org)

That technical limitation is central to the paper's message. The authors concluded that simultaneous advancement and lateralization can be achieved with an oblique osteotomy and a standard TTA cage, but they also flagged limited freehand accuracy and suggested cutting guides may improve consistency. That idea already appears to be moving forward: a separate 2026 ex vivo study described patient-specific 3D-printed ALBA osteotomy guides designed for FONT and reported that the guides may support more precise execution, while also emphasizing that in vivo studies are still needed before clinical applicability is clear. (orthovetsupersite.org)

The broader orthopedic literature helps explain why a simplified combined approach would attract attention. A 2017 study comparing fixation methods in 72 stifles found complications were 2.7 times more frequent with extracapsular stabilization plus tibial tuberosity transposition than with tibial tuberosity transposition and advancement, and major complications occurred only in the former group. Other cited work in the field has evaluated combined TPLO and TTT, modified TPLO techniques, and deformity-correcting osteotomies, reflecting an ongoing search for procedures that can correct both pathologies without adding instability, implant problems, or alignment errors. (pubmed.ncbi.nlm.nih.gov)

Why it matters: For veterinary professionals, FONT is less a ready-to-adopt procedure than an early signal about where combined stifle surgery may be heading. The appeal is clear: one osteotomy, standard TTA hardware, and a geometry-based way to deliver both advancement and lateralization. But the current evidence base is narrow. This was a computational and cadaver study in dogs roughly 15.8 to 25.3 kg, not a prospective clinical series, and it did not address healing, meniscal outcomes, reluxation, implant complications, rehabilitation, or longer-term function. For surgeons, the practical takeaway is that the concept looks biomechanically plausible, but precision appears to be the make-or-break issue. (orthovetsupersite.org)

That also means case selection will matter if FONT moves into clinical use. MPL with CrCL disease is often accompanied by additional femoral, tibial, or torsional deformities, and those patients may still need more than a tibial tuberosity-based correction alone. In that sense, FONT may prove most useful in a subset of dogs whose pathology can be adequately addressed by controlled advancement and lateralization, rather than in every dog with concurrent disease. That is an inference based on the broader MPL literature and the design limits of the current study, not a direct claim from the authors. (todaysveterinarypractice.com)

What to watch: Watch for the first in vivo clinical series, complication reporting, and whether patient-specific guides become part of the technique's standard workflow, because those data will determine whether FONT remains an interesting cadaver concept or becomes a practical option in referral orthopedics. (pubmed.ncbi.nlm.nih.gov)