S2 Alar Screw Insertion Accuracy and Factors Associated With Screw Loosening and Lumbosacral Nonunion.

OBJECTIVE: To investigate S2 alar screw (S2AS) accuracy and factors associated with S2AS loosening and lumbosacral nonunion. METHODS: We retrospectively reviewed patients who underwent lumbosacral fusion surgery with S2AS addition under fluoroscopy. S2AS loosening and lumbosacral nonunion were analyzed using a 1-year postoperative computed tomography. S2AS insertion accuracy was originally classified as accurate, short, anterior perforation, lateral perforation, and sacroiliac joint (SIJ) deviation among lateral perforation. Clinical data including sex, age, body mass index, fused segments, fusion procedure, primary or revision surgery, Japanese Orthopedic Association scores and complications were collected. Factors associated with S2AS loosening and lumbosacral nonunion were analyzed. RESULTS: A total of 37 patients (74 screws, age: 63.78 ± 13.57 years, female/male: 14/23 patients, body mass index: 23.11 ± 2.53, fused segments: 1-4 levels, revision: 38%) were included. S2AS loosening and lumbosacral nonunion were observed in 18 screws (13%) and 8 patients (22%) respectively. Only 35 screws (47%) were inserted accurately in our classification. Short, lateral perforation, and anterior perforation were observed in 14 screws (19%), 22 screws (30%), and 3 screws (4.1%). SIJ deviation was seen in 15 screws (20%) Factors associated with S2AS loosening were older age (P = 0.038), fusion levels (P = 0.011), and SIJ deviation (P < 0.001). S2AS loosening affects S1 pedicle screw (S1PS) loosening (P = 0.001). Furthermore, S2AS loosening is a risk factor for lumbosacral nonunion (P = 0.046). CONCLUSIONS: S2AS insertion under fluoroscopy is inaccurate. S2AS loosening induces S1PS loosening and lumbosacral nonunion. Surgeons should avoid deviating to SIJ, especially in older patients and relatively longer fusion.

Feasibility of total and partial uncinectomy during anterior cervical approach: MRI-based analysis of 176 patients regarding vertebral artery location.

PURPOSE: To determine the technical feasibility of uncinate process (UP) resection (uncinectomy) during anterior cervical approach with risk-avoidance of vertebral artery (VA) injury. METHODS: One hundred and seventy-six magnetic resonance imaging images with cervical spondylosis were evaluated. The diameter between UP and VA (UP-VA distance), the presence of a fat plane, and the VA's anterior-posterior position relative to UP (anterior[A], middle[M], posterior[P]) at C3-4 to C6-7 segments were investigated. Subsequently, easy-to-use classifications were developed according to the feasibility of total and partial uncinectomy. Total uncinectomy: easy (distance: > 2 mm); moderate (distance: ≤ 2 and fat plane: +); advanced (no fat plane). Partial uncinectomy: easy (distance: > 2 mm and P, A, or M position); moderate (distance: ≤ 2; fat plane: + and P position), and advanced (no fat plane and P position). RESULTS: UP-VA distance of C5-6 on the right side (left/right: 0.41/0.31 mm) was the smallest. The ratio of no fat plane of C5-6 (46.6%/49.4%) was the highest. C5-6 had a high rate of P position (7.4%/8.5%) while C6-7 had a high rate of A position (19.3%/18.2%). More than 90% individuals were classified as easy for partial uncinectomy at any vertebral segment (C3-7), while more than 30% were classified as advanced at C4-7 with the highest rate at C5-6 for total uncinectomy. CONCLUSION: When performing uncinectomy during the anterior cervical approach, the C5-6 segment may be at the greatest risk of VA injury. Hence, preoperative MR images should be thoroughly evaluated to avoid VA injury.

CT-based analysis of sagittal and coronal lumbar endplate morphology: multivariate analysis of factors associated with endplate depth.

PURPOSE: Lumbar endplate morphology varies in individuals; thus, custom-made implants are sometimes more useful than standardized implants. This study aimed to analyze endplate morphology and factors associated with endplate depth using computed tomography (CT) in a non-symptomatic population. METHODS: In total, 118 lumbar CT images of non-symptomatic individuals without severe degenerative change (aged 20-79 years) were retrospectively reviewed. The following radiographic parameters were measured in each lumbar vertebral segment (T12-S1) to determine endplate depth: superior/inferior endplate depth in the midsagittal and midcoronal planes, disk angle, and height. The relationship between baseline demographics (age, sex, body mass index [BMI], Hounsfield unit of the L1 vertebral body, and pelvic incidence [PI]) and endplate depth was analyzed. RESULTS: Toward the caudal level, the superior endplate depth increased, sagittal inferior depth decreased, and coronal inferior depth increased. Multivariate analysis revealed that endplate depth was significantly associated with age (p < 0.001), while inferior endplate depth was associated with PI (p = 0.01). Superior endplate depth was associated with female sex (sagittal: p = 0.005, coronal: p = 0.002). Endplate depth, except for the inferior coronal region, was associated with low BMI (sagittal superior: p = 0.005; coronal superior and sagittal inferior: p = 0.02). CONCLUSION: Endplate depths tend to be larger toward the caudal level, particularly in the superior endplate. Surgeons should thoroughly evaluate the preoperative CT image because various endplate morphologies require attention to cage shape when performing lumbar interbody fusion, especially in patients who are older, are female, have low BMI, and have large PI. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Non-invasive early prediction of immune checkpoint inhibitor efficacy in non-small-cell lung cancer patients using on-treatment serum CRP and NLR.

PURPOSE: We determined the clinical relevance of early C-reactive protein (CRP) and neutrophil-lymphocyte ratio (NLR) change in blood as surrogate markers of pro-tumor inflammation (PTI) for predicting clinical outcome of programmed cell death (PD)-1/programmed cell death ligand (PD-L) 1 inhibitor treatment in non-small-cell lung carcinoma (NSCLC). METHODS: We retrospectively reviewed NSCLC patients treated with anti-PD-1 or PD-L1 inhibitors. Early CRP change was defined as the ratio of 6 weeks CRP to baseline CRP, and early NLR change was defined as that of the 6 weeks NLR to baseline NLR. PTI index was determined by combinatorial evaluation of early CRP change and early NLR change, PTI index low: both of these were low, intermediate: either of these was low, high; both of these were high. RESULTS: The study included 217 patients. Early CRP change and early NLR change were both associated with PFS and OS. The combinatorial evaluation using these two markers enabled the clear stratification of PFS and OS. The median PFS in patient with PTI index low was 13.9 months, while the median PFS in those with PTI index high was 2.5 months (p < 0.01, log-rank test). The median OS in patients with PTI index low was not reached; the median OS in those with PTI index high was only 15.4 months (p < 0.01, log-rank test). CONCLUSIONS: The combinatorial early CRP change and early NLR change as PTI biomarkers have clinical potential in identifying NSCLC patients who can achieve a durable response and long-term survival using PD-1/PD-L1 inhibitors.

Lateral Interbody Fusion for Hyperlordosis and Negative Sagittal Vertical Axis Because of Accordion Phenomenon: A Case Report.

CASE: The accordion phenomenon is defined as the difference in the disc space observed on x-ray or computed tomography images taken in both standing and supine positions, which results in a discrepancy of local spinal alignment. Oblique lateral interbody fusion (OLIF) is a less invasive method of potentially correcting both coronal and sagittal spinal alignment. We present the case of a 66-year-old woman with rheumatoid arthritis treated with OLIF for degenerative disc disease presenting with hyperlordosis and negative sagittal vertical axis (SVA) because of the accordion phenomenon. CONCLUSION: OLIF for severe degenerative disc disease presenting with hyperlordosis and negative SVA because of the accordion phenomenon may be effective.

Substantially High Hidden Blood Loss in Oblique Lateral Interbody Fusion: Retrospective Case Series.

Background and Objectives: Measured blood loss frequently underestimates true blood loss; this discrepancy is called hidden blood loss (HBL). The purpose of the present study was to measure HBL in oblique lateral interbody fusion (OLIF). Materials and Methods: Patients who underwent two-stage OLIF at our institute from September 2017 to September 2021 were retrospectively reviewed. Total blood loss (TBL) and HBL were calculated using the gross formula. The age, sex, body mass index (BMI), operation time, measured blood loss, the number of fused segments, hematocrit (HCT), anticoagulant or platelet medication, blood transfusion, days of hospitalization, pre-/postoperative Japanese Orthopedic Association (JOA) score, and JOA recovery rate were compared. Results: A total of thirteen patients were included in the study. The average age, BMI, number of fused segments, operation time, estimated blood loss, and blood transfusion were 69.5 years, 23.3, 2.5, 250 min, 122 mL, and 230 mL, respectively. Five patients received anticoagulant or platelet therapy. Days of hospitalization, pre-/postoperative JOA score, and JOA recovery rate were 14.9 ± 5.1, 19.9 ± 2.7, and 18.0 ± 43.4%, respectively. The TBL and HBL were 688 and 797 mL, respectively. Stepwise multiple regression analysis revealed that younger age (p = 0.01), female sex (p = 0.01), and number of fused segments (p = 0.02) were significantly associated with higher HBL. Conclusions: The HBL in OLIF was 797 mL, which was more than other previously reported procedures. Therefore, OLIF may not be less invasive in terms of HBL. Blood loss after surgery should be considered, especially when patients are younger, are female, and have a greater number of fused segments.

Tibial Tubercle-Trochlear Groove Distance Influences Patellar Tilt After Total Knee Arthroplasty.

BACKGROUND: Tibial tubercle-trochlear groove (TT-TG) distance is associated with a greater risk of recurrent patellar dislocation in young, active patients. However, the effect of TT-TG distance after total knee arthroplasty (TKA) has not been investigated. The purpose is to analyze the effect of TT-TG distance and component rotation on patellar tilt and patellar shift after TKA. METHODS: After TKA, axial computed tomography scans and axial radiograph were taken in 115 consecutive knees. TT-TG distance was measured between the most anterior point of the tibial tuberosity and the deepest point of the femoral component relative to a line connecting the anterior condyles. Femoral and tibial component rotation was measured relative to the femoral and tibial rotational axis, respectively. Pearson correlation coefficients were calculated. RESULTS: TT-TG distance had a significant correlation with patellar tilt in extension (R = 0.220, P = .018), patellar tilt in flexion (R = 0.438, P < .001), and patellar shift (R = 0.330, P < .001). Tibial component rotation had a significant correlation with patellar tilt in flexion (R = -0.251, P = .007) and patellar shift (R = -0.360, P < .001). Femoral component rotation had no significant correlations. Tibial component rotation had a significant correlation with TT-TG distance (R = -0.573, P < .001), whereas femoral component rotation had no correlation (P = .192). CONCLUSION: TT-TG distance had a significant correlation with patellar tilt and patellar shift. Surgeons need to understand the factors affecting TT-TG distance and to pay attention to avoiding excessive TT-TG distance after TKA.

Factors influencing spinal sagittal balance, bone mineral density, and Oswestry Disability Index outcome measures in patients with rheumatoid arthritis.

PURPOSE: To identify the factors influencing spinal sagittal alignment, bone mineral density (BMD), and Oswestry Disability Index (ODI) outcome measures in patients with rheumatoid arthritis (RA). METHODS: We enrolled 272 RA patients to identify the factors influencing sagittal vertical axis (SVA). Out of this, 220 had evaluation of bone mineral density (BMD) and vertebral deformity (VD) on the sagittal plane; 183 completed the ODI questionnaire. We collected data regarding RA-associated clinical parameters and standing lateral X-ray images via an ODI questionnaire from April to December 2012 at a single center. Patients with a history of spinal surgery or any missing clinical data were excluded. Clinical parameters included age, sex, body mass index, RA disease duration, disease activity score 28 erythrocyte sedimentation rate (DAS28-ESR), serum anti-cyclic citrullinated peptide antibody, serum rheumatoid factor, serum matrix metalloproteinase-3, BMD and treatment type at survey, such as methotrexate (MTX), biological disease-modifying anti-rheumatic drugs, and glucocorticoids. We measured radiological parameters including pelvic incidence (PI), lumbar lordosis (LL), and SVA. We statistically identified the factors influencing SVA, BMD, VD, and ODI using multivariate regression analysis. RESULTS: Multivariate regression analysis showed that larger SVA correlated with older age, higher DAS28-ESR, MTX nonuse, and glucocorticoid use. Lower BMD was associated with female, older age, higher DAS28-ESR, and MTX nonuse. VD was associated with older age, longer disease duration, lower BMD, and glucocorticoid use. Worse ODI correlated with older age, larger PI-LL mismatch or larger SVA, higher DAS28-ESR, and glucocorticoid use. CONCLUSIONS: In managing low back pain and spinal sagittal alignment in RA patients, RA-related clinical factors and the treatment type should be taken into consideration.

[A case of pulmonary carcinosarcoma with pleural effusion, progressive pleural thickening and a calcification-like lesion].

A 70-year-old man was admitted to our hospital with dyspnea. Chest X-ray film revealed right pleural effusion. Chest CT showed right pleural effusion with slight pleural thickening and a patchy calcification-like lesion. Adenocarcinoma cells were detected in pleural effusion, but upper gastrointestinal endoscopy, barium enema examination and ultrasonography of the abdomen failed to show the primary lesion. We made a diagnosis of primary adenocarcinoma of the lung. Chemotherapy was performed after pleurodesis. However there was gradual increase of right pleural thickening and expansion of the calcification-like lesions. The patient died 16 months after his first visit. Pathological findings of the autopsy specimen revealed the tumor composed of an adenocarcinomatous component and an osteosarcomatous component. The final diagnosis was primary carcinosarcoma of the lung.

[A case of pulmonary inflammatory pseudotumor accompanied with increased serum immunoglobulin G levels and autoimmune pancreatitis].

A 77-year-old man with increased serum immunoglobulin G levels and autoimmune pancreatitis was found to have a chest X-ray abnormality. The chest X-ray and CT films showed a mass shadow in the right lower lobe and lymphadenopathy. Since transbronchial tumor biopsy did not obtain diagnostic material, CT-guided cutting needle biopsy was performed. The microscopic findings showed plasma cells and lymphocytes infiltrating the pleura and alveolar interstitium. A diagnosis of inflammatory pseudotumor was suspected, but it was difficult to exclude malignancy. Therefore, wedge resection of the right lower lobe including the mass and incisional biopsy of mediastinal lymph nodes were performed. Histopathologic examination of the resected specimen revealed inflammatory pseudotumor that was predominantly composed of mature plasma cells infiltrating in the bronchiolar wall, peribronchiolar interstitial tissue, alveolar wall, visceral pleura, the diaphragmatic area of the parietal pleura and mediastinal lymph nodes. Immunohistochemical staining revealed many IgG4-positive plasma cells diffusely infiltrated in the resected mass and lymph nodes. In this case, there is a possibility that patient developed autoimmune pancreatitis, pulmonary inflammatory pseudotumor and lymphadenopathy as part of systemic IgG4-related

[Three cases of transcatheter embolization for pulmonary arteriovenous fistula using detachable coils].

We report three cases of transcatheter embolization for pulmonary arteriovenous fistula (PAVF) using Interlocking detachable coils (IDC) and detachable fibered coils (DFC), and evaluate the outcome of transcatheter embolization with reference to previous reports. The three patients were women aged 56, 70 and 71 years. They had no symptoms, but chest radiographs were abnormal. None of them had Rendu-Osler-Weber disease. The three PAVFs were of the simple type, with a single feeding vessel and a single draining vein. In case 1, the feeding vessel arose from the left A4, while the feeding vessels in case 2 and 3 arose from the left A5. In case 1, we embolized the venous sac with detachable coils because the feeding vessel was short and kinked. In case 2 and 3, we embolized the feeding vessels closer as to the neck of the venous sac using detachable coils. The three PAVFs were all successfully embolized without severe complications, and transcatheter embolization seems to be an effective therapy.