CT and MRI characteristics of presumptive hypervitaminosis A in a cat.

CASE SUMMARY: A rescued stray cat with an unknown history was examined for non-ambulatory paraparesis in the hindlimbs. Survey radiographs revealed typical findings of hypervitaminosis A, characterised by vertebral exostoses and extensive osteophytes, mainly in the cervicothoracic spine. CT findings were consistent with the radiographic findings, and CT-based volume rendering and virtual endoscopy into the vertebral canal were created for three-dimensional visualisation of the lesion. MRI revealed a focal and mild dilation of the central canal of the spinal cord. Although the clinical diagnosis of hypervitaminosis A is based on an unusual dietary history and characteristic radiographic findings, the history of this cat was unknown and serum concentrations of vitamin A were unremarkable, when measured >1 month after rescue. However, other possible differential diagnoses were thought to be unlikely and clinical signs never worsened, and thus, hypervitaminosis A was presumed. RELEVANCE AND NOVEL INFORMATION: To our knowledge, this is the first report to present the CT and MRI characteristics of a cat with suspected hypervitaminosis A.

Encapsulated gas accumulation in the spinal canal: Pneumorrhachis in two dogs.

A 17-year-old mongrel dog and 12-year-old Shiba Inu dog presented with ataxia and paresis of the pelvic limbs, respectively. Gas accumulation within the spinal canal adjacent to the herniated disc was suspected in both cases. Since the gas remained accumulated for a prolonged period, hemilaminectomy was performed to decompress the spinal cord. The bulged external lamina of the dura matter was removed and histopathologically examined. Granulomatous inflammation and hyperplasia of fibrous connective tissues was noted, suggesting that the gas was encapsulated and the fibrous nodules made reabsorption difficult. Clinical signs resolved post-surgery. This is the first report describing histopathological features of pneumorrhachis in dogs. The accumulated gas was successfully removed by surgery. Postoperative course remained uneventful in both cases.

Validation study of a diagnostic scoring system for sacroiliac joint-related pain.

BACKGROUND: There are no specific radiological findings for the diagnosis of sacroiliac joint-related pain. A diagnostic scoring system had been developed in 2017. The score comprised the sum of scores of six items. The score ranged from 0 to 9 points, and the cutoff was calculated as 4. OBJECTIVE: To evaluate the validity of the diagnostic scoring system for sacroiliac joint-related pain. PATIENTS AND METHODS: The sacroiliac joint-related pain group (n=31) comprised patients diagnosed with sacroiliac joint-related pain based on patient history, physical findings, and responses to analgesic periarticular injection. In addition, it was confirmed that they had no other lumbar or hip joint diseases. The non-sacroiliac joint-related pain group (n=123) comprised patients with low back pain due to a reason other than sacroiliac joint-related pain. We evaluated scores for all subjects. We analyzed the differences in each item between both groups and performed receiver-operating characteristic curve analysis to evaluate the score validity. RESULTS: There were no significant differences in patient characteristics between groups. There were significant differences for the following four of six items: one-finger test results (P<0.0001), pain while sitting on a chair (P=0.0141), sacroiliac joint shear test results (P<0.0001), and tenderness of the posterosuperior iliac spine (P<0.0001). The cut-off value was 5 points, the area under the curve was 0.80239, sensitivity was 77.4%, and specificity was 76.4%. CONCLUSION: The score demonstrated moderate validity for diagnosing sacroiliac joint-related pain.

Evidence-based Care Bundles for Preventing Surgical Site Infections in Spinal Instrumentation Surgery.

STUDY DESIGN: A retrospective study, using prospectively collected data. OBJECTIVE: The aim of this study was to evaluate the impact of evidence-based care bundles for preventing surgical site infections (SSIs) in spinal instrumentation surgery. SUMMARY OF BACKGROUND DATA: About half of all SSIs are preventable via evidence-based methods. For successful SSI prevention, the bacterial load must be minimized, and methicillin-resistant Staphylococcus aureus (MRSA) protection must be maximized. However, it is difficult to cover all of these requirements by single preventative method. METHODS: We screened consecutive patients scheduled for spinal instrumentation surgeries at a single tertiary referral hospital for high surgical, SSI, and MRSA colonization risks. Evidence-based care bundles were implemented for high-risk patients and included 1) additional vancomycin prophylaxis, 2) diluted povidone-iodine irrigation, and 3) nasal and body decontamination. Patient demographics, comorbidities, operative features, and SSIs reported to the Japanese Nosocomial Infections Surveillance system were prospectively obtained in the same method by the same assessor and were used for the analyses. The results were compared before and after the application of the bundle. RESULTS: There were 1042 spinal instrumentation surgeries (741 before and 301 after care bundles) performed from November 2010 to December 2015. Of 301 surgeries, 57 cases (18.9%) received care bundles. There were no significant differences in patient backgrounds before and after the intervention. The SSI rate decreased significantly from 3.8% to 0.7% (P < 0.01) after the intervention, with an overall 82% relative risk reduction. A significant protective effect was observed in the multivariate analysis (adjusted odds ratio 0.18, 95% confidence interval: 0.04-0.77, P = 0.02). There were no MRSA-related SSIs among those that received care bundles, even though MRSA was the predominant pathogen in the study population. CONCLUSION: Evidence-based care bundles, applied in selected high-risk spinal instrumentation cases, minimized bacterial load, maximized MRSA protection, and significantly reduced SSI rates without topical vancomycin powder. LEVEL OF EVIDENCE: 4.

Spondylolysis repair using a pedicle screw hook or claw-hook system. -a comparison of bone fusion rates.

INTRODUCTION: To assess the bone fusion rates and clinical results of two surgical methods (pedicle screw claw-hook fixation and pedicle screw hook fixation) of lumbar spondylolysis repair. METHODS: A multicenter database of surgical patients with lumbar spondylolysis was reviewed. All patients < 20 years old with a minimum of 6 months of follow-up and computed tomography images were included. Operation time and blood loss amount were investigated. Visual analogue scale (VAS; 0-10) scores for lower back pain were evaluated to assess clinical results. RESULTS: A total of 17 patients met the inclusion criteria. Pedicle screw hook fixation was performed in five patients (the hook group), and pedicle screw claw-hook fixation was performed in 13 patients (the claw-hook group). One patient was included in both groups because each method was performed at different lumbar levels (L4 and L5). The bone fusion rates at 3, 6, and 9 months after surgery were significantly higher in the claw-hook group than those in the hook group. Operation time and blood loss amount were not significantly different between the groups. VAS scores improved in the claw-hook group but not in the hook group because of a small number of patients. CONCLUSIONS: Pedicle screw claw-hook fixation was more effective than pedicle screw hook fixation in terms of bone fusion rates.

A novel closed-wedge high tibial osteotomy procedure to treat osteoarthritis of the knee: hybrid technique and rehabilitation measures.

High tibial valgus osteotomy (HTO) is an established treatment for medial-compartment osteoarthritis of the knee. We have combined medial open and lateral closed-wedge HTO (hybrid closed-wedge HTO) to overcome the limitations of traditional closed-wedge HTO. Our new hybrid procedure has the following advantages: (1) the bone block removed is smaller in size; (2) the procedure yields optimal geometric characteristics for bone healing; (3) there is no step-off at the lateral osteotomy site; (4) the lateral cortex of the proximal and distal fragments is attached firmly by the oblique osteotomy; and (5) early full weight-bearing walking is possible. This procedure is effective in treating medial-compartment osteoarthritis accompanied by patellofemoral osteoarthritis. The indications for this procedure include a willingness and ability to comply with the postoperative rehabilitation program; a diagnosis of either medial-compartment osteoarthritis or complicated patellofemoral osteoarthritis; and preferably, an age of 70 years or younger, although this is not a strict constraint. Patients are permitted to stand using both legs on the day after surgery and walk with full weight bearing within 2 weeks of undergoing our novel HTO procedure. We describe the details of this surgical technique and the postoperative rehabilitation program for the patients who undergo this treatment.

Low-intensity pulsed ultrasound accelerates fracture healing by stimulation of recruitment of both local and circulating osteogenic progenitors.

We investigated the effect of low-intensity pulsed ultrasound (LIPUS) on the homing of circulating osteogenic progenitors to the fracture site. Parabiotic animals were formed by surgically conjoining a green fluorescent protein (GFP) mouse and a syngeneic wild-type mouse. A transverse femoral fracture was made in the contralateral hind limb of the wild-type partner. The fracture site was exposed to daily LIPUS in the treatment group. Animals without LIPUS treatment served as the control group. Radiological assessment showed that the hard callus area was significantly greater in the LIPUS group than in the control group at 2 and 4 weeks post-fracture. Histomorphometric analysis at the fracture site showed a significant increase of GFP cells in the LIPUS group after 2 weeks (7.5%), compared to the control group (2.4%) (p < 0.05). The LIPUS group exhibited a significantly higher percentage of GFP cells expressing alkaline phosphatase (GFP/AP) than the control group at 2 weeks post-fracture (5.9%, 0.3%, respectively, p < 0.05). There was no significant difference in the percentage of GFP/AP cells between the LIPUS group (2.0%) and the control group (1.4%) at 4 weeks post-fracture. Stromal cell derived factor-1 and CXCR4 were immunohistochemically identified at the fracture site in the LIPUS group. These data indicate that LIPUS induced the homing of circulating osteogenic progenitors to the fracture site for possible contribution to new bone formation.