Talonavicular Subchondral Fracture Healing on MRI Post Single Autologous Fat-Derived Expanded Mesenchymal Stem Cell Therapy: A Case Report

A talonavicular fracture is a form of foot fracture that involves the talus and the navicular bones. This sort of fracture is typically triggered by a sudden injury. Management of talonavicular fracture commonly involves immobilizing the foot and ankle with a cast or brace to allow the bones to heal properly. In some instances, surgery could be necessary to realign the bones to ensure appropriate healing. This article presents a middle-aged female, a professional Pilates teacher who suffered an injury to her left talonavicular joint (TNJ) which led to chondral injury and subchondral talar fracture, with an accelerated traumatic TNJ osteoarthritis. She had significant symptoms that interfered with her daily activities and work. She failed anti-inflammatory medicine, intra-articular steroid, and platelet-rich plasma (PRP) combined with hyaluronic acid injections. She was offered surgical debridement of cartilage and fusion of the TNJ, instead, she elected experimental intra-articular autologous fat-derived expanded mesenchymal (MSCs) combined with PRP. She reported dramatic clinical improvement two months post-therapy, and a gradual return to her loved work with an MRI six months post-treatment revealing bone remodeling and complete healing of the fracture with associated articular and peri-articular high signals hypothesizing inflammatory healing response rather than the pathological inflammation given she had significant improvement of her clinical presentation and function. This case demonstrates the use of MSC therapy combined with PRP as a non-surgical approach in traumatic chondral injuries and subchondral fracture letting joint fusion as a last resort. Of note, she failed the intra-articular trial of PRP combined with hyaluronic acid while a positive result was achieved when expanded MSCs were combined with PRP as a superior regenerative therapy. We need a large randomized controlled trial to confirm our findings.