Coronoid fractures and complex elbow instability: current concepts.

Fractures of the coronoid process typically occur as part of more complex injury patterns, such as terrible triads, trans-olecranon fracture-dislocations, posteromedial rotatory injuries or Monteggia-like lesions. Each pattern is associated with a specific type of coronoid fracture with regard to shape and size and specific soft-tissue lesions. O' Driscoll classification incorporates those associations identifying three major types of fractures: tip, anteromedial facet, and basal fractures. The objective of this study is to review the most common types of complex elbow instability, identify the indications for coronoid fixation and guide the appropriate management. Tip fractures as those seen in terrible triads can conditionally left untreated provided that elbow stability has been restored after radial head fixation and ligaments repair. Anteromedial facet fractures benefit from a buttress plate, while large basilar fractures can be effectively secured with posteroanterior screws. Coronoid reconstruction with a graft should be considered in post-traumatic cases of chronic coronoid deficiency.

A staged procedure for the treatment of chronic patellar tendon ruptures after total knee arthroplasty.

The management of extensor mechanism lesions after total knee replacement is still associated with an unacceptably high complication rate, especially in its chronic setting. In this study, we report on 4 patients with chronic (> 3 months) patellar tendon rupture after knee arthroplasty, who were treated with a novel procedure of staged patella advancement prior to reconstruction with autografts. Initially, a unilateral frame was applied connecting the patella with the tibial shaft. The construct allowed for gradual distal advancement of the patella based on the Ilizarov principles. After achieving the desired patella height, the frame was removed, and the patellar tendon was reconstructed with hamstrings. All four patients experienced a significant improvement in extensor lag by a mean of 38.0°, while Knee society scores increased by a mean of 38.5 units. No substantial loss in active knee flexion was observed. Our findings suggest that our technique yields favorable outcomes in patients with patellar tendon disruption in the setting of a total knee arthroplasty.

Interobserver Reliability of Schatzker, AO Foundation-Orthopaedic Trauma Association, and Luo Classifications for Tibial Plateau Fractures: Does Three-Dimensional CT Improve Outcomes?

Objective To assess the interobserver agreement of the most widely used classification systems (Schatzker, AO Foundation-Orthopaedic Trauma Association (AO-OTA), and Luo) and investigate the impact of multiplane CT scans on their reliability. Methods Twelve raters (seven consultants and five senior trainees) were invited to classify 25 cases of tibial plateau fracture randomly selected out of a large database. Initially, they were asked to classify the fracture according to Schatzker, AO-OTA, and Luo based on plain anteroposterior (AP) X-ray and axial CT images. This procedure was applied for 25 cases consecutively. Next, the raters are given access to the multiplanar CT views of the same cases and were requested to reclassify each case. The interobserver agreement was calculated using the Fleiss kappa coefficient. Results An overall fair inter-rater agreement was observed for the Schatzker classification based on the plain AP X-ray (k=0.361) with a slight improvement after three-dimensional (3D) plane CT views (X-ray: k=0.361; 3D CT: k=0.364). For the AO-OTA classification, the relevant values were 0.204 and 0.231 based on plain X-ray and multiplanar CT, respectively. Finally, the Luo classification achieved the highest scores among the three classification systems (k=0.498), but its inter-rater agreement can still be characterized as moderate. No statistically significant improvement in the interobserver agreement was found for any classification even if only the consultants' subgroup was included in the data analysis. Conclusion All three classification systems failed to achieve a substantial agreement among the raters, with only a nonsignificant improvement after providing advanced imaging. This finding reflects the intrinsic weaknesses of the classification systems themselves rather than the disagreement on the fracture pattern due to unsatisfactory imaging.