What Affects Segmental Lordosis of the Surgical Site after Minimally Invasive Transforaminal Lumbar Interbody Fusion?

PURPOSE: This study was undertaken to identify factors that affect segmental lordosis (SL) after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) by comparing patients whose postoperative SL increased with those whose decreased. MATERIALS AND METHODS: Fifty-five patients underwent MIS-TLIF at our institute from January 2018 to September 2019. Demographic, pre- and postoperative radiologic, and cage-related factors were included. Statistical analyses were designed to compare patients whose SL increased with decreased after surgery. RESULTS: After surgery, SL increased in 34 patients (group I) and decreased in 21 patients (group D). The index level, disc lordosis, SL, lumbar lordosis, proximal lordosis (PL), and Y-axis position of the cage (Yc) differed significantly between groups I and D. The cage in group I was more anterior than that in group D (Yc: 55.84% vs. 51.24%). Multivariate analysis showed that SL decreased more significantly after MIS-TLIF when the index level was L3/4 rather than L4/5 [odds ratio (OR): 0.46, p=0.019], as preoperative SL (OR: 0.82, p=0.037) or PL (OR: 0.68, p=0.028) increased, and as the cage became more posterior (OR: 1.10, p=0.032). CONCLUSION: Changes in SL after MIS-TLIF appear to be associated with preoperative SL and PL, index level, and Yc. An index level at L4/5 instead of L3/4, smaller preoperative SL or PL, and an anterior position of the cage are likely to result in increased SL after MIS-TLIF.

The Fate of Proximal Junctional Vertebral Fractures after Long-Segment Spinal Fixation : Are There Predictable Radiologic Characteristics for Revision surgery?

OBJECTIVE: To investigate the radiographic characteristics of the uppermost instrumented vertebrae (UIV) and UIV+1 compression fractures that are predictive of revision surgery following long-segment spinal fixation. METHODS: A total 27 patients who presented newly developed compression fracture at UIV, UIV+1 after long segment spinal fixation (minimum 5 vertebral bodies, lowest instrumented vertebra of L5 or distal) were reviewed retrospectively. Patients were divided into two groups according to following management : revisional surgery (group A, n=13) and conservative care (group B, n=14). Pre- and postoperative images, and images taken shortly before and after the occurrence of fracture were evaluated for radiologic characteristics. RESULTS: Despite similar degrees of surgical correction of deformity, the fate of the two groups with proximal junctional compression fractures differed. Immediately after the fracture, the decrement of adjacent disc height in group A (32.3±7.6 mm to 23.7±8.4 mm, Δ=8.5±6.9 mm) was greater than group B (31.0±13.9 mm to 30.1±15.5 mm, Δ=0.9±2.9 mm, p=0.003). Pre-operative magnetic resonance imaging indicated that group A patients have a higher grade of disc degeneration adjacent to fractured vertebrae compared to group B (modified Pfirrmann grade, group A : 6.10±0.99, group B : 4.08±0.90, p=0.004). Binary logistic regression analysis indicated that decrement of disc height was the only associated risk factor for future revision surgery (odds ratio, 1.891; 95% confidence interval, 1.121-3.190; p=0.017). CONCLUSION: Proximal junctional vertebral compression fractures with greater early-stage decrement of adjacent disc height were associated with increased risk of future neurological deterioration and necessity of revision. The condition of adjacent disc degeneration should be considered regarding severity and revision rate of proximal junctional kyphosis/proximal junction failures.

Incorporating New Technologies to Overcome the Limitations of Endoscopic Spine Surgery: Navigation, Robotics, and Visualization.

Recently, spine surgery has gradually evolved from conventional open surgery to minimally invasive surgery, and endoscopic spine surgery (ESS) has become an important procedure in minimally invasive spine surgery. With improvements in the optics, spine endoscope, endoscopic burr, and irrigation pump, the indications of ESS are gradually widening from lumbar to cervical and thoracic spine. ESS was not only used previously for disc herniations that were contained without migration but is also used currently for highly migrated disc herniations and spinal stenosis; thus, the indications of ESS will be further expanded. Although ESS has certain advantages such as less soft tissue dissection and muscle trauma, reduced blood loss, less damage to the epidural blood supply and consequent less epidural fibrosis and scarring, reduced hospital stay, early functional recovery, and improvement of quality of life as well as better cosmesis, several obstacles remain for ESS to be widespread because it has a steep learning curve and surgical outcome is strongly dependent on the surgeon's skillfulness. A solid surgical technique requires reproducibility and ensured safety in addition to surgical outcomes. In this review article, how to improve ESS was investigated by grafting novel technologies such as navigation, robotics, and 3-dimensional and ultraresolution visualization.

Surgical Treatment in Patients with Cervical Osteomyelitis: Single Institute's Experiences.

OBJECTIVE: To study practical guidelines and strategies in the treatment of cervical osteomyelitis. METHODS: We retrospectively reviewed 14 patients who underwent surgical treatment for cervical osteomyelitis from May 2000 to July 2008. We investigated their clinical course, antibiotic regimen, surgical methods, and laboratory and radiologic findings including X-ray, CT and MRI. RESULTS: 5 patients had primary spondylodiscitis, 5 patients had post operative spondylodiscitis and 4 patients had tuberculosis in cervical spine. The causative microorganisms were MRSA (5), P. aeruginosa (1), Methicillin resistant coagulase negative streptococcus (1), P. aeruginosa changed to MRSA (1), and 2 patients showed no growth on culture studies. Patients were treated 13.8 weeks (range, 5.4-25.8) with IV antibiotics and then treated for 58.2 days (range, 13-106) with oral antibiotics. Antituberculotic medications were used for a mean of 383.8 days. Patients were treated with anterior debridement and fusion (5), irrigation and debridement (5), simultaneous cervical anterior interbody and transthoracic thoracic interbody fusion (1). 3 patients underwent the planned 2-staged operation, which included an anterior debridement with or without fusion for the 1(st) operation and posterior instrumentation for 2(nd) operation. 10 patients (71.4%) had neurologic deficits at the time of diagnosis and 7 patients (70%) among them improved post-operatively. CONCLUSION: Anterior cervical spine surgery is the preferable treatment option in patients with neurological deterioration, extensive bony destruction with expected kyphotic deformity, and uncontrolled infection being managed only with antibiotics. Antibiotics are also important for thorough treatment.

Use of Annular Closure Device (Barricaid®) for Preventing Lumbar Disc Reherniation: One-Year Results of Three Cases.

Although lumbar discectomy is an effective treatment for lumbar disc herniation, complications exist, including postoperative disc height loss, facet joint degeneration, and recurrent disc herniation. To solve these problems, annular closure devices have been utilized in other countries, producing satisfactory results, but there has been no report of annular closure device use in our country. Here, we demonstrate the preliminary reports of Barricaid® insertion in 3 patients who underwent surgery for lumbar disc herniation.