Minimally invasive plate osteosynthesis: Where is the evidence?

The principles of minimally invasive plate osteosynthesis are based on preserving blood supply by minimizing exposure and disruption of the fracture site. These principles can be applied to different fixation techniques such as external fixation, intramedullary pinning, lag screws and plating. Minimally invasive plate osteosynthesis (MIPO) encompasses these principles because it does not invade the fracture site. Percutaneous plating involves the application of a bone plate without making an extensive surgical approach to expose the fracture site. The bone segments are reduced using indirect reduction techniques. Small plate insertion incisions are made at each end of the fractured bone and an epi-periosteal tunnel is made connecting those incisions. The plate is inserted through one of the insertion incisions and tunneled along the periosteal surface of the bone, spanning the fracture site. Screws are applied at the proximal and distal ends of the plate through the insertion incisions or if necessary, through additional stab incisions. Screws are not placed in the holes located in the central portion of the plate, which is often positioned over the fracture. Despite MIPO has become increasingly common in both human and veterinary orthopedics, very few studies have investigated technique, outcome, and complications. In addition, there are few studies comparing MIPO to ORIF.

As with most techniques, there are both advantages and disadvantages associated with MIPO. Operative time is reduced compared to anatomic reconstruction once familiarity with the procedure is developed. Minimally invasive procedures carry less of a risk of bacterial infection in comparison to open reconstruction procedures due to shorter duration of surgery, less soft tissue trauma and decreased potential for intra-operative contamination of the fracture site. The fracture hematoma is not removed at surgery and may contribute to increased rate of callus formation. Fractures stabilized with MIPO should heal in a similar manner to fractures stabilized with external skeletal fixation applied in a closed fashion, but would require less patient and fixator care in the post-operative convalescence period. There are some obvious disadvantages associated with MIPO. The technique can be technically challenging to learn and apply. MIPO may not be suitable for simple fractures and articular fractures which require precise anatomic reduction and compression. MIPO does not allow direct visualization of the fracture site, therefore, access to intra-operative fluoroscopy or radiography greatly facilitates the surgical procedure.  [...]