Efficiency of various options for surgical treatment and prevention of proximal junctional kyphosis in patients with lumbar spine deformities and concomitant osteoporosis

Objective. To conduct a comparative analysis of the effectiveness of various options for the prevention of proximal junctional kyphosis (PJK) in the surgical treatment of adult patients with deformities of the lumbar spine, including taking into account the degree of correction of the lumbar lordosis. Material and Methods. The results of instrumental fixation of the spine performed in 140 adult patients with severe frontal spinal deformity and/or sagittal imbalance corresponding to types III and IV according to Berjano and Lamartina were studied. The patients were divided into 4 clinical groups depending on the methods of surgical treatment: in 36 cases, correction of lumbar lordosis of no more than 30° was performed without the use of PJK prevention methods (Group I); in 24 – the same correction was supplemented with laminar fixation of the vertebra above the fusion zone (Group II); 20 patients underwent complete restoration of the sagittal and frontal balance with prophylactic vertebroplasty of the superjacent vertebra above the zone of instrumental fixation (Group III); and in 60 – the same intervention was performed without the use of the PJK prevention  methods (Group IV). Results. Statistically significant differences in lumbar lordosis, difference in the pelvic angle and lumbar lordosis, and displacement of the sagittal vertical axis were found between the pairs of groups I and II, and III and IV. Postoperative values of the index of the proximal junctional angle (PJA) in patients of Group II differed significantly from the corresponding indicators of other groups. A statistically significant increase in the PJA after surgery was found in patients of groups III and IV. There was a statistically significant decrease in PJK cases in Group II in comparison with other groups (p = 0.001), as well as more pronounced trend to decrease in pain intensity and ODI score. Laminar fixation of the superjacent vertebra leads to a decrease in local kyphosis over the area of instrumental fixation and reduces the load on the ventral parts of the vertebra. Prophylactic vertebroplasty (Group III) provides better results compared to a comparable cohort (Group IV). Conclusion. Partial correction of lumbar lordosis (no more than 30°) and preventive laminar fixation of the superjacent vertebra showed significantly better clinical results (by more than 50 %; p = 0.001) compared with the other three clinical groups in terms of reducing the level of pain and improving the quality of life, as well as of decrease in number of cases of PJK development – by 16–28 % (p = 0.001).