Results of application of the new protocol of functional multispiral computer tomography in patients with lateral instability and the syndrome of lateral hyperpressure of the patella

Purpose. To develop an optimal protocol for describing functional multispiral computed tomography (fMSCT) of the knee joint for patients with lateral instability of the patellofemoral articulation (PFA) and hyperpression of the lateral patellar facet. Materials and methods. The study included 52 patients aged 18 to 49 years with symptoms of lateral patellofemoral instability and suspicion of hyperpression of the lateral patellar facet according to clinical and instrumental data. All patients underwent fMSCT of the knee joint according to the developed technique during extension in the knee joint from the 60° flexion position. After performing fMSCT, a description of the data was carried out according to the proposed protocol with the determination of the degrees of lateral instability and hyperpression of the lateral patellar facet according to our classification. Results. After evaluating the fMSCT data according to the proposed protocol, signs of grade 1 of lateral articulation instability were noted in 23.1% of cases (n=12), grade 2 - in 38.5% of cases (n=20), and grade 3 - in 30.8% of cases (n=16). The grade 2 of lateral facet hyperpression was observed in 44.2% of cases (n=23), the grade 1 - in 36.5%, n=19. In 11.5% of patients (n=6) with grade 2 of hyperpression and grade 2 of instability, the management tactics were changed to surgical. The high position of the patella was noted in 23% of patients (n=12), the Wiberg type II configuration was noted in 21.1% of cases (n=11), type II-III- in 51.9% of cases (n=27), type III - in 27% of cases (n = 14). In 32.7% of patients (n=17) degenerative-dystrophic changes in the PFA were described, and their effect on the biomechanics of the joint was assessed. In 44.2% of patients (n=23) who were shown surgical treatment when assessed according to the developed algorithm, description protocols were supplemented with 3D and 4D reconstructions with video visualization, which were used by orthopedic traumatologists when planning surgery.Conclusions. The developed protocol for describing fMSCT of the knee joint includes an assessment of all indicators of lateral instability of the PFA and hyperpression of the lateral facet of the patella, reflects a maximum of information about the violation of the biomechanics of the joint, allows us to identify the degree of pathological changes and choose the optimal type of treatment (using the classification of pathological changes according to fMSCT data, which we proposed in 11.5% of cases (n = 6) allowed to change the tactics of patient management). Supplementing the protocol with 3D- and 4D-reconstructions with video visualization in combination with methods of mathematical modeling enables orthopedic traumatologists to apply a personalized approach in planning treatment of lateral instability of the PFA and hyperpression of the lateral facet of the patella.