First Human Use of a Patient-Specific 3-Dimensional-Printed Titanium Interbody Implant for High-Grade Dysplastic...

Advancements in 3-dimensional (3D) printing have enabled the development of patient-specific implants tailored to complex anatomical and biomechanical challenges in spine surgery. This technology is especially valuable in disorders such as dysplastic spondylolisthesis, where congenital lumbosacral anomalies create severe challenges for standard interbody implant placement. We present the first use of a Puri-Ti (DeGen Medical, Florence, SC, USA) patient-specific anterior lumbar interbody fusion (ALIF) cage system. The implant was utilized under the Food and Drug Administration (FDA) Expanded Access (Compassionate Use) pathway with Institutional Review Board approval. This case demonstrates the feasibility and potential advantages of custom 3D-printed implants in addressing complex lumbosacral deformity.

A 38-year-old man presented with progressive low-back and bilateral lower-extremity symptoms secondary to high-grade dysplastic spondylolisthesis at L5 to S1. Imaging demonstrated severe anterior translation of L5, dome-shaped sacral morphology, and bilateral foraminal stenosis. Owing to the patient's severe dysplastic anatomy, standard ALIF cages could not be safely implanted without extensive osteotomy. A patient-specific 3D-printed titanium ALIF implant was designed in collaboration with the manufacturer. The device was inserted via an anterior retroperitoneal approach, followed by posterior percutaneous instrumentation and decompression. Postoperative radiographs and computed tomography imaging confirmed appropriate implant seating, partial reduction of the spondylolisthesis, and restoration of foraminal height. The patient experienced resolution of preoperative radiculopathy and returned to full function by 1 year.

Patient-specific 3D-printed implants offer a promising solution for spinal pathology in which conventional implants cannot achieve adequate fit, biomechanical stability, or safe insertion. The successful outcome in this case supports the role of personalized interbody implants in carefully selected patients with dysplastic anatomy and highlights the need for further study in larger cohorts.

Standard interbody implants often fail to accommodate the distorted sacral dome morphology characteristic of high-grade dysplastic spondylolisthesis, frequently requiring complex and high-risk bone osteotomies to achieve adequate seating. This case report demonstrates that a patient-specific, 3D-printed titanium ALIF cage can successfully restore alignment, promote stable fusion, and resolve radicular symptoms by matching the patient's unique anatomy exactly. Utilizing custom 3D-printed implants provides a safe, highly conforming, and effective surgical alternative for complex spinal deformities where off-the-shelf devices are anatomically incompatible.