ObjectiveTo summarize the research progress on spontaneous facet fusion (SFF) after lumbar spine surgery, and provide reference for further research on SFF. Methods The definition, development, clinical significance, and related influence factors of SFF were throughout reviewed by referring to relevant domestic and foreign literature in recent years. Results SFF is a phenomenon of joint space disappearance and fusion of upper and lower articular processes, which starts in a ring shape from the outermost edges to the central regions. Currently reported SFF occurred after posterior lumbar pedicle screw fixation. SFF may increase the stability of surgical segments and relieve clinical symptoms of patients. SFF is closely related to the method of lumbar internal fixation, facet osteoarthritis, interbody fusion, age, body mass index, type B fracture (according to AO classification), and the operative segment. Conclusion Most reported SFF occur after posterior lumbar pedicle screw fixation, which can increase lumbar stability, but the mechanism and influencing factors remain to be further clarified.
Objective To summarize the effect of cage height on outcomes of lumbar interbody fusion surgery and the importance of the cage height selection. Methods The related literature was widely reviewed to summarize the research progress on the complications caused by inappropriate height of the cage and the methods of selecting cage height. Results Inappropriate height of the cage can lead to endplate injury, cage subsidence, internal fixation failure, adjacent segmental degeneration, over-distraction related pain, insufficient indirect decompression, instability of operation segment, poor interbody fusion, poor sequence of spine, and cage displacement. At present, the selection of the cage height is based on the results of the intraoperative model test, which is reliable but high requirements for surgical experience and hard to standardize. ConclusionThe inappropriate height of the cage may have an adverse impact on the postoperative outcome of patients. It is important to develop a selection standard of the cage height by screening the related influential factors.
ObjectiveTo summarize the advances in research on Cage subsidence following lumbar interbody fusion, and provide reference for its prevention.MethodsThe definition, development, clinical significance, and related risk factors of Cage subsidence following lumbar interbody fusion were throughout reviewed by referring to relevant domestic and doreign literature in recent years.ResultsAt present, there is no consensus on the definition of Cage subsidence, and mostly accepted as the disk height reduction greater than 2 mm. Cage subsidence mainly occurs in the early postoperative stage, which weakens the radiological surgical outcome, and may further damage the effectiveness or even lead to surgical failure. Cage subsidence is closely related to the Cage size and its placement location, intraoperative endplate preparation, morphological matching of disk space to Cage, bone mineral density, body mass index, and so on.ConclusionThe appropriate size and shape of the Cage usage, the posterolateral Cage placed, the gentle endplate operation to prevent injury, the active perioperative anti-osteoporosis treatment, and the education of patients to control body weight may help to prevent Cage subsidence and ensure good surgical results.
Objective To summarize research progress on application of Cup-cage reconstruction in revision of chronic pelvic discontinuity (CPD) in patients undergoing total hip arthroplasty (THA). Methods Relevant literature at home and abroad in recent years was reviewed to summarize the principles of the Cup-cage reconstruction, preoperative patient assessment, intraoperative skills, clinical and radiological effectiveness, limitations, and postoperative complications.Results For the treatment of CPD, the Cup-cage reconstruction achieved long-term acetabular cup bone ingrowth, CPD healing, and biologic fixation of the prosthesis by restoring pelvic continuity. Preoperative evaluation of the surgical site and general condition is necessary. The main intraoperative objectives are to reconstruct pelvic continuity, restore the center of rotation of the hip, and avoid neurovascular injury. Current studies have demonstrated significant clinical and radiological effectiveness as well as acceptable prosthesis survival rates after operation. Nevertheless, there is a lack of evidence regarding the staging of CPD, the optimal surgical approach and internal fixation, and the factors influencing postoperative prosthesis survival remain undefined. Conclusion Cup-cage reconstruction can be an effective treatment for CPD after THA, but there is still a need to explore CPD staging, Cup-cage approach and internal fixation, and influencing factors on prosthesis survival.