Materials and Methods: We searched the databases of our institutions for the surgical procedures diagnosed as "fracture of the radial head" and for the procedures related to "prosthesis of the radial head" and "osteosynthesis of the radial head" in the period from May 2014 to October 2017. The fractures were first classified according to the Mason classification . We then allocated the patients into three study groups according to the site of the fracture, either the medial or lateral side of the radial head : Group A, with an isolated lateral fracture of the radius head; Group B1, with a medial fracture of the radius head with two medial fragments; and Group B2, with a medial fracture of the radius head with multiple medial fragments. We performed a multivariate analysis to identify statistically significant correlation between the pre-operative classifications of Mason and our study, the type of surgical procedure, and the clinical outcome.
Results: Mayo Elbow Performance (MEP) scores determined at the final follow-up of the study (mean 16.6 months, range 12-26 months) was excellent in 17 patients (4 in Group A, 6 in Group B1 and 7 in Group B2), and good in 12 patients (3 in Group A, 7 in Group B1, and 2 in Group B2). One patient showed a poor result in MEP score probably because of an infection and implant removal.
Conclusion: Regarding medial fractures of the radial head, our study showed satisfactory results with a radial head prosthesis for comminuted or multifragmentary radial head fractures. For surgeons with advanced elbow fracture expertise, osteosynthesis could be attempted in a fracture pattern that involved only two medial fragments.
Case Report: Case Report 1: Mrs P, a 27-year-old right-hand dominant female, was involved in a motor vehicle accident (MVA) and sustained an isolated Regan-Morrey type III ulnar coronoid process fracture. In view of the large coronoid process fragment causing elbow joint instability, she underwent an open reduction and internal fixation when the elbow swelling had subsided. An anterior approach was used to identify the fracture fragment and it was fixed with two half-threaded cancellous lag screws with washers to achieve an anatomical reduction. Postoperatively, she recovered with excellent outcome based on the Mayo elbow performance score (MEPS).Case Report 2: Mr M, a 23-year-old right-hand dominant gentleman, was involved in a MVA and sustained an isolated Regan-Morrey type III ulnar coronoid process fracture. During examination under general anesthesia, passive range of the movement of his right elbow was noted to be <90°due to the impaction of the fracture fragment. An open reduction through an anterior approach was performed and Kirschner wires were inserted to fix the coronoid process fracture. Kirschner wires were opted for the ease of post-operative removal as the patient was not keen to have a retained implant after recovery. He recovered with good outcome based on the MEPS.
Conclusion: Isolated fracture of the ulnar coronoid process is rare. Open reduction and internal fixation is mandatory for patients with coronoid process fracture and unstable elbow joint to achieve good functional outcomes.