Syringe-Assisted Arthroscopic Implantation of Particulated Juvenile Articular Cartilage for Trochlear Cartilage Defects.

Particulated juvenile articular cartilage (PJAC) allograft has emerged as a single-stage biologic option for treatment of focal full-thickness cartilage defects, including isolated trochlear lesions. Open techniques are most commonly described, and although a small number of arthroscopic techniques have been reported, precise placement of particulate graft material within the curved geometry of the trochlea remains technically challenging due to high local shear forces, limited working angles, and difficulty maintaining a dry arthroscopic field. We describe a fully arthroscopic technique for the implantation of PJAC allograft in a trochlear cartilage defect using a standard 1-mL disposable tuberculin syringe to facilitate controlled, titratable graft delivery and uniform particulate distribution. The technique is demonstrated in a representative case and includes defect preparation with creation of stable vertical cartilage shoulders, removal of the calcified cartilage layer, transition to a dry arthroscopic field, syringe-assisted graft placement, and stabilization with fibrin sealant. Syringe-assisted delivery enabled controlled placement of cartilage particulates with uniform distribution under direct arthroscopic visualization, facilitating creation of a thin monolayer flush with the surrounding articular surface. The patient initially progressed through rehabilitation without wound or infectious complications and maintained full knee motion. Postoperative magnetic resonance imaging demonstrated incorporation of the lateral trochlear PJAC implant without delamination or subchondral bone plate disruption. In the setting of a complex prior surgical history, multifocal patellofemoral chondral disease, and persistent activity-related mechanical symptoms, the patient later underwent repeat diagnostic arthroscopy approximately 16 months after PJAC implantation. A standard disposable tuberculin syringe provides a simple, reproducible, and cost-efficient method for improving graft control during arthroscopic PJAC implantation in the trochlea, leveraging widely available instrumentation rather than specialized delivery systems. This technique may help reduce technical barriers to minimally invasive cartilage restoration in anatomically constrained regions of the patellofemoral joint.