Practical guidelines for the treatment of patellar fractures in adults

The role of the patella is paramount in the transmission of the quadriceps muscle forces, the increase of the lever arm, the distribution of the forces on the trochlea and the centring of the extensor apparatus. Despite the low incidence of patellar factures in comparison with other lower limb fractures, the painful and functional complications, such as knee stiffness, loss of extension and patellofemoral osteoarthritis, can be very disabling and will often compromise the return to a professional or recreational activity and induce falls in the elderly population. Treatment can be conservative or surgical, provided that it is adapted to the type of fracture. Undisplaced fractures with an intact extensor mechanism can be treated non-operatively. Surgical treatment is recommended for fractures that either disrupt the extensor mechanism or have more than 2 to 3 mm of step-off and more than 1 to 4 mm of displacement. Tension band fixation is the most commonly employed surgical technique. In most cases, hardware has to be removed after fracture healing because of implant-related pain. Operative treatment of comminuted patellar fractures presents a significant challenge to surgeons. Failure to restore the articular surface contour results in posttraumatic arthritis. Anatomical reconstruction of the articular surface is the only way to prevent the development of posttraumatic osteoarthritis. Typically, fracture classification and thus treatment choice are based on anteroposterior and lateral radiographs of the knee, but when computed tomography of the knee was performed pre-operatively, both the classification and treatment were modified thanks to a better understanding of the fracture complexity. The purpose of this article is to review current treatment strategies and optimise the management of adult patients with patellar fractures.