Objective
To investigate the association of quantitative paraspinal muscle measurements to the Oswestry disability index (ODI) in patients with lumbar spondylolisthesis.
Materials and Methods
Ninety two patients (mean age, 61.6 years; male, mean age, 71.8 years ; female; mean body mass index [BMI], 24.9 kg/m² ) who had undergone lumbar fusion due to spondylolisthesis with available selfcompleted postoperative ODI were included. The total cross-sectional area (CSA) and functional CSA (FCSA; i.e., area containing only lean muscle tissue) of the paraspinal muscle group (multifidus and erector spinae muscles) and the psoas muscles were measured at L2–L3, L3–L4, and L4–L5 disc levels each on preoperative magnetic resonance imaging (MRI) and the sum of areas at each level served as representative values for each muscle. The FCSA/total CSA ratio and the skeletal muscle index (SMI=muscle area [cm² ]/patient height2 [m² ]) were calculated. Pearson’s correlation analyses were performed to evaluate the relationship between preoperative paraspinal muscle measurements and postoperative ODI.
Results
Quantitative values of low paraspinal muscle showed significant correlation with high ODI values. As a result of this study, the preoperative paraspinal muscle was quantified in the group of patients undergoing spinal fusion. Patients with low value in CSA and FCSA of paraspinal muscle could observe the tendency to transition to low clinical outcomes. Therefore, quantitative values of surrounding muscles are factors affecting clinical outcomes of patients undergoing spinal surgery Conclusion: Smaller muscle bulk (total CSA) of psoas muscles and lean muscle mass (FCSA) of paraspinal muscle group and psoas muscles combined on preoperative MRI were associated with significant postoperative disability based on ODI in patients with lumbar spondylolisthesis.

Background
Proximal junctional kyphosis (PJK) following long instrumented fusion is a well-recognized complication that does not negatively affect the clinical outcomes. However, there were few studies with regard to the long-term consequences of PJK. Objective: To investigate the long-term clinical and radiographic consequences of proximal junctional kyphosis (PJK) following the long instrumented fusion for elderly patients with sagittal imbalance.
Methods
Patients older than 60 years who underwent ≥4 fusion including the sacrum for sagittal imbalance were followed up longer than five years. PJK was defined as proximal junctional angle (PJA) >10° without any bony compromise or myelopathy. The radiographic and clinical outcomes were compared between PJK and non-PJK groups. Clinical outcome measures included visual analog scale (VAS) for back and leg, Oswestry disability index (ODI), and Scoliosis Research Society (SRS)-22 scores.
Results
A mean age was 69.2 years. An average follow-up duration was 92.4 months. There were 30 patients in PJK group and 43 in non-PJK group. At the final follow-up, pelvic incidence-lumbar lordosis mismatch, pelvic tilt, and sacral vertical axis were not different between the two groups. In PJK group, PJA significantly increased from 6.5° postoperatively to 21.2° at the final follow-up. At the final follow-up, clinical outcomes were worse in PJK group than in non-PJK group with regard to VAS for back, ODI, and SRS-22 scores except satisfaction domain. Three (10%) of 30 patients underwent a revision surgery for PJK progression.
Conclusions
PJK progressed with time and negatively affect the clinical outcomes in a long-term follow-up after ASD surgery.

Numerous improvements in minimally invasive spine surgery (MISS) have been made during the past decade. Classic treatment methods have reserved surgical intervention for trauma patients with neurological compromises or instability. When used in thoracolumbar spine trauma management, MISS should achieve the similar results as classic treatment with less morbidity.(1) In the past decade, minimally invasive surgical (MIS) techniques for spine surgery have been increasingly used. The goal of minimally invasive surgery is to decrease surgical morbidity through decreased soft-tissue dissection providing similar structural stability as classic techniques. An increasing number of studies is reporting good clinical and radiographic outcomes with MIS techniques. However, the literature is lacking high-quality evidence comparing these newer techniques to classic treatments. In the future, development of techniques can expand the indications and treatment possibilities in spine trauma treatment. We reviewed the current literatures to clarify the indications of minimally invasive techniques with spinal trauma.

Lumbar fusion surgery for lumbar degenerative diseases has increased in the past several decades and many techniques for fusion surgery have been introduced. Recently lateral lumbar interbody fusion with minimally invasive technique was introduced and accepted as a useful method for various lumbar degenerative disease. It can produce good correction for sagittal and coronal imbalance with relatively decreased morbidity. The advantage of lateral lumbar interbody fusion is that it can avoid injury to the abdominal large vessels and neural structures which is more common during posterior approaches. However various complications had been reported. Complications related with lateral lumbar interbody fusion include neurologic complications including thigh pain and numbness, vascular complications including arterial injury, cage related complication such as cage subsidence and vertebral body fractures. Therefore special care should be taken to avoid possible complications in lateral lumbar interbody fusion surgery.

Objectives
to report a surgical site infection from Aspergillus after a lumbar discectomy. Aspergillus is ubiquitous fungus. People with normal immunity are usually not infected by it, however, surgical site infection from it often developed even in normal population.
Materials and Methods
The diagnostic and therapeutic experience of 55-year-old male patient who underwent L45 discectomy who had surgical site infection from Aspergillus was reviewed.
Results
He had 4 times surgical treatment and empirical antibiotic therapy due to progressive extension of infection without microbiologic confirmation. Aspergillus flavus was identified at 5th operation and he was cured by adding an anti-fungal agent.
Conclusions
An Aspergillus infection after an operation can be developed even in normal immunity population. If a surgical site infection patient without fever and draining sinus does not improve by conventional treatment, Aspergillus infection should be considered.