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Length-weight relationships (LWRs) were developed for 85 reef and bottom-fish species from Guam. These are the first published LWRs for Guam, and include new LWRs for nine species lacking these relationships in Fish-Base. [ABSTRACT FROM AUTHOR]

STUDY DESIGN.: Case-control study. OBJECTIVE.: To assess the long-term prevalence of vertebral fractures after lumbar spinal fusion with instrumentation. SUMMARY OF BACKGROUND DATA.: The incidence of the adjacent and the nonadjacent, remote level subsequent vertebral fractures after lumbar spinal fusion is not well described in the literature. METHODS.: The study is a retrospective analysis of 100 consecutive patients of 55 years of age or older with spinal fusion for degenerative diseases between L1 and S1, and instrumentation for less than 4 segments. Patients with prevalent vertebral fractures defined at the time of surgery, or patients with secondary causes of osteoporosis were excluded. Mean follow-up period was 10.2 years (range, 7-14 years). Acute vertebral fractures were determined by magnetic resonance imaging and lateral spine radiographs. RESULTS.: Acute vertebral fractures were determined in 20 vertebrae in 14 (24%) of the 59 female patients, whereas 1 male patient (2%) had 1 vertebral fracture during the follow-up period. Eighteen of the 21 fractures occurred within 2 years of the spinal instrumentation surgery. Regarding time to fracture occurrence after surgery, adjacent level fractures occurred within 8 months, and remote level fractures occurred between 8 and 22 months after surgery. CONCLUSION.: Postmenopausal female patients who underwent lumbar spinal instrumentation surgery were susceptible to develop subsequent vertebral fractures within 2 years after surgery. The greater the number of spinal segments between the fracture and the instrumentation was, the longer the time after surgery. [ABSTRACT FROM AUTHOR]

Study Design: A case-control study. OBJECTIVE.: To measure the orientation of the facet joints at both cephalad and caudad portions and to compare them between patients with degenerative spondylolisthesis (DS) and patients with lumbar spinal stenosis (LSS, controls). Summary Of Background Data: Several radiologic studies have indicated a correlation between DS and an increased sagittal orientation of the facet joints. However, the orientation of the facet joints have only been measured on 1 axial cut of computed tomography scans and magnetic resonance imaging. Methods: Thirty-two patients with DS only at the L4-L5 level were assigned to group-1, and 28 patients with LSS without DS were assigned to group-2. Two computed tomography scans for the cephalad and caudad portions of the facet joint were made for L3-L4 and L4-L5 levels, respectively. Delta facet angle was defined as facet angle (cephalad)-facet angle (caudad). Results: Facet angles of the cephalad portion were more sagittally oriented (P < 0.001) than those of the caudad portion in group-1. The mean facet angle of the cephalad portion was 72 degrees and that of the caudad portion was 57 degrees at L4-L5. The mean facet angle of the cephalad portion at L4-L5 was greater (P = 0.001) in group-1 (72 degrees ) than in group-2 (62 degrees ). Delta facet angles were significantly greater in group-1 than in group-2. Mean delta facet angle was 15 degrees in group-1 and 2 degrees in group-2 at L4-L5 (P < 0.001), and 4 degrees and 0 degrees , respectively, at L3-L4 (P = 0.046). Conclusion: In this study, we confirmed that the cephalad portion of the facet joints were more sagittally oriented and that the caudad portion of the facet joints were more coronally oriented in patients with DS. These findings were observed not only at L4-L5 but also at the uninvolved L3-L4 level in patients with DS at the L4-L5 level. [ABSTRACT FROM AUTHOR]

Study Design: A prospectively study. Objective: Our objective was to clarify the safety and efficacy of asymmetrical pedicle subtraction osteotomy (PSO) in the treatment of severe adult lumbar deformities prospectively. Summary Of Background Data: Vertebral wedge osteotomy provides good correction of kyphosis but has rarely been applied to degenerative lumbar kyphoscoliosis. Methods: A total of 14 patients who had undergone corrective osteotomy were enrolled. The average age at PSO was 67 years (range, 45-76 yr). The minimum follow-up was 2 years. Patient questionnaires were administered prospectively. Radiographical parameters including sagittal and coronal balance were analyzed. Results: Average operative time was 310 minutes (range, 254-375 min). Average blood loss was 1090 mL (range, 700-2900 mL).Mean preoperative lumbar lordosis improved from -3° to 42° at the final follow-up, and sagittal balance improved from 12 to 3 cm, respectively. Mean lumbar scoliosis improved from 40° to 12°, and coronal offset improved from 3 to 1 cm, respectively. There was also statistically significant improvement from preoperative to final evaluation in all clinical domains. There were 4 complications: 1 dural tear, 2 hook dislodgements at the cephalad side requiring revision instrumentation, and 1 rod breakage not requiring surgical intervention. Overall, all 14 patients were satisfied with their surgical management and would choose to repeat the procedure. Conclusion: Our data suggest that the surgical procedure of asymmetrical PSO is to correct the scoliosis, to restore the lumbar lordosis by way of convex-sided posterolateral wedge osteotomy, and may go a long way toward solving the problems of rigid lumbar degenerative kyphoscoliosis. [ABSTRACT FROM AUTHOR]