Emerging Options for Biologic Enhancement of Stress Fracture Healing in Athletes

Timothy L. Miller, MD; Christopher C. Kaeding, MD; Scott A. Rodeo, MD


J Am Acad Orthop Surg. 2020;28(1):1-9. 

In This Article

Subchondral Calcium Phosphate Bone Substitute

Subchondral injection of calcium phosphate bone substitute is a recently developed surgical technique whose application includes the treatment of subchondral insufficiency fractures most commonly of the distal femur and proximal tibia by providing structural support to areas of decreased bone mineral density.[27] Authors have additionally described its use in the foot and ankle including the treatment of bone marrow lesions of the talus and calcaneus.[28–30] This procedure is performed by drilling into metaphyseal subchondral bone with a cannulated fluted guide pin (Figure 4). Under fluoroscopy, engineered calcium phosphate paste is injected into subchondral bony defects forming a macroporous scaffold for bone to increase the density and possibly improve the structural integrity of subchondral bone. Initial results of the procedure have shown that over the first 24 weeks following the procedure, recipients reported notable relief from pain and improvement in functional capacity.[31] A recent review of eight studies by Astur et al[32] indicated that subchondral calcium phosphate injection for the treatment of 164 patients with bone marrow lesions of the femoral condyle and tibial plateau allowed markedly improved pain and knee function with an average time of 3 months to return to full activity. It should be noted that these surgical techniques have been developed and used for treatment of subchondral insufficiency fractures, which are much more common in the setting of early degenerative joint disease rather than athletic stress fractures. Data on its use in stress fractures in athletes is minimal, although its use in this population is increasing.

Figure 4.

Intraoperative anterior-posterior fluoroscopy image of the proximal tibia after injection of calcium phosphate paste through a fluted cannulated drill. A blush of increased density is noted in the surrounding medial metaphyseal bone.