Research Progress Of Proximal Junctional Kyphosis And Failure After Spinal Deformity Surgery

Spinal deformity is not uncommon in clinical patients.The kyphosis or scoliosis of the spine not only lead to somatic sagittal and coronal position unbalanced,but also causing patients with intractable low back pain due to the lumbar vertebral compensatory excessive lordosis.At the same time,spinal deformity can also cause serious psychological burden and inconvenience on the life and work.In addition,severe spinal deformity of kyphosis can also affect the patient's heart and lung function,and cause spinal cord function damage.Therefore,correction of spinal deformity not only improve the appearance of patients with deformity,more importantly,to improve the patient's heart and lung function and relieve nerve damage plays a vital role in the prevention and treatment.With the development of internal fixation and the development of various osteotomy operation,different types of spinal deformity can be corrected through the long segment osteotomy,fixation,fusion of spinal orthopedic surgery to alleviate the spinal deformity,neurological symptoms and sagittal and coronal loss.Thereby improving the patients' quality of life.However,the occurrence of postoperative adjacent segmental pathology for the recovery of symptoms after surgery,orthopedic angle maintenance is a threat.In many complications after spinal orthopedic surgery,proximal junctional kyphosis and proximal junctional failure may result in increased sagittal unbalanced or severe neurological damage,and some patients require surgical intervention to resolve them symptoms.Because of PJK and PJF description and concept has not been established,it received widespread attention.Through the systematic review of the literatures,we found that the risk factors of PJK after spine orthopedic surgery were:older age(>55 years);large abnormal preoperative sagittal parameters;posterior and anterior-posterior spinal fusion;fusion to the lower lumbar spine and sacrum;the use of pedicle screws;thoracoplasty procedures;obesity(BMI>30)and osteoporosis.Occurrence mechanism:extensive paraspinal muscle dissection at the upper instrumented vertebra;disruption of the supraspinous and interspinous ligaments(posterior tension band);improper end-vertebra selection;proximal severe disc degeneration;compression fracture at the most instrumented vertebra;compression fracture at the most instrumented vertebra;facet violation.Therefore,through the study of the occurrence and development of postoperative PJK,the risk factors and mechanism of development will help the clinician to reduce or avoid the above-mentioned risk factors before,during and after surgery,and thus avoid the PJK,alleviate the symptoms of patients,and improve patient quality of life.