fig4

Figure 4. Complications: B group: Balloon kyphoplasty in the upper instrumented vertebra (UIV)/UIV + 1 to prevent proximal junctional kyphosis; P group: circumferential minimally invasive surgery (c-MIS) using 5.5 mm rods; 6P group: c-MIS using 6 mm rods; M group: multi-rod c-MIS. PJK: Proximal junctional kyphosis; RF: rod fracture.