Search

Purpose: The purpose of this study is to develop guidelines for clinical trial of the total ankle replacement system for premarket approval. Materials and Methods: We selected and analyzed nine peer-reviewed articles whose quality had been proven in a previous phase. Two investigators extracted parameters for guideline criteria, including number of cases, patient age, follow-up period, failure rate, radiographic osteolysis rate, residual pain rate, and percentage of satisfaction. In addition, the inclusion and exclusion criteria were analyzed and developed. Results: Eight level IV studies and one level II study were included. The average number of cases was 159 cases and the mean patient age was 63.5 years. The mean follow-up period was 4.2 years, ranging from two to nine. The average failure rate of total ankle replacement in mid- to long-term follow-up was approximately 13% (2%~32.3%). The rate of osteolysis was approximately 18%. Residual pain was common (21.4%~46%), but overall patient satisfaction was approximately 85.6% (67.5%~97%). Conclusion: The results could be used as criteria for designing the clinical studies, such as number of cases, patient age (over 60 years), and follow-up period (minimum two years). The clinical scoring system and 36-item short form health survey (SF-36) was the most commonly used method for clinical evaluation for total ankle arthroplasty. In addition, the overall results, including failure rate, osteolysis rate, and patient satisfaction, could be used as a parameter of guidelines for premarket approval. [ABSTRACT FROM AUTHOR]

Background: Falls are a major factor contributing to fragility fractures. Patients with lumbar spinal stenosis have an increased risk of falling. We are aware of no prior report demonstrating the effect of medical treatment and decompression surgery on the risk of patients with lumbar spinal stenosis falling. Methods: From June to November 2011, seventy-six patients were enrolled into the surgery group and fifty patients, into the nonoperative group. Four functional mobility tests, including the Alternate-Step test, Six-Meter Walk test, Sit-to-Stand test, and timed "Up&Go" test,wereused toevaluate therisk of falling. The Oswestry Disability Index (ODI) and the EuroQoL-5D (EQ-5D) visual analog scale (VAS) were utilized to assess clinical improvement. Results: The mean age was 62.4 years in the surgery group and 64.6 years in the nonoperative group. The results of the Alternate-Step test significantly improved during the follow-up period in the surgery group (p = 0.001). However, the results of the Alternate-Step test significantly worsened during the follow-up period in the nonoperative group (p = 0.001). Comparison between the two groups showed more significant improvement in the surgery group, especially for the Six- Meter Walk test at one year postoperatively (p = 0.042) and for the timed "Up & Go" test at three months and one year (p = 0.046 and 0.000). However, the ODI and EQ-5D VAS scores improved in both groups. In a linear mixed model, age, surgery, and the presence of an osteoporotic compression fracture significantly affected the test results related to the risk of falling (p < 0.05). Conclusions: The surgery group showed a greater decrease in the risk of falling than those in the nonoperative group. Improved physical performance, including walking and balancing, after decompression lumbar spinal surgery reduces the future risk of falling. Level of Evidence: Therapeutic Level II. Retrospective analysis of prospectively collected data. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Hematogeneous infectious spondylodiscitis usually occurs in older immunocompromised patients with other comorbidities. They are usually unable to undergo reconstructive anterior and posterior surgeries. Therefore, an alternative, less aggressive surgical method of transpedicular curettage and drainage was suggested. This study was designed to compare the surgical outcomes for the treatment of hematogeneous infectious spondylodiscitis between transpedicular curettage and drainage technique and conventional combined anterior and posterior surgery. Materials and Methods: Between January 2002 and July 2011, 26 patients underwent surgical treatment for hematogeneous infectious spondylodiscitis. The patients were classified into two groups depending on surgical modality: a transpedicular curettage and drainage (TCD) group and a combined anterior and posterior surgery (CAPS) group. Results: The TCD group consisted of 10 patients (mean age 68.0 years), and the CAPS group consisted of 16 patients (mean age 58.4 years).The mean postoperative followup periods were 36.9 (months) in the TCD group and 69.9 (months) in the CAPS group. The operation time was 180.6 ± 33.6 minutes in the TCD group and 332.7 ± 74.5 minutes in the CAPS group (P < 0.05). Postoperative independent ambulation began at postoperative 4.9 ± 2.4 days in the TCD group but at postoperative 15.1 ± 15.3 days in the CAPS group (P < 0.05). The postoperative hospital stays were 19.9 ± 7.8 days in the TCD group and 35.4 ± 33.3 days in the CAPS group (P < 0.05). The level of C-reactive proteins decreased significantly in both groups after surgery (P < 0.05). Conclusion: Transpedicular curettage and drainage technique proved to be a useful technique for treating hematogeneous infectious spondylodiscitis in patients who were in poor heath with multiple comorbidities unable to undergo the conventional combined anterior and posterior surgery in a single day in terms of earlier ambulation, shorter hospitalization and similar clinical success rate. [ABSTRACT FROM AUTHOR]

Study Design: This is a retrospective study. Purpose: To evaluate the effect of the dynamic rotational plate to the intervertebral foraminal and discal height after anterior cervical discectomy and fusion. Overview of Literature: There is no report regarding the changes of foraminal and discal height following cervical dynamic rotational plating. Methods: We reviewed the outcomes of 30 patients (36 levels), who were followed-up for an average of 15 months (range, 12−57 months) after undergoing fusions with anterior cervical dynamic rotational plating for cervical radiculopathy, from March 2005 to February 2009. The changes of foraminal and intervertebral discal height of the operated levels were observed on oblique and lateral radiographs obtained at the preoperative, postoperative and follow-up examinations. Results: The foraminal and discal height increased sufficiently, immediately following the operation. However, follow-up results showed gradual decrease in the foraminal and discal height. After 6 months of the surgery, they showed little difference compared with the preoperative heights. However, clinically, patients showed improvements in radiating pain during the follow-up period. Conclusions: Anterior cervical dynamic rotational plating was an effective treatment modality for cervical radiculopathy without the deterioration of the foraminal and intervertebral discal height. [ABSTRACT FROM AUTHOR]

A method for stably purifying a functional dye, phycocyanin from Spirulina platensis was developed by a hexane extraction process combined with high pressure. This was necessary because this dye is known to be very unstable during normal extraction processes. The purification yield of this method was estimated as 10.2%, whose value is 3%-5% higher than is the case from another conventional separation method using phosphate buffer. The isolated phycocyanin from this process also showed the highest purity of 0.909 based on absorbance of 2.104 at 280 nm and 1.912 at 620 nm. Two subunits of phycocyanin namely ɑ-phycocyanin (18.4 kDa) and ß-phycocyanin (21.3 kDa) were found to remain from the original mixtures after being extracted, based on SDS-PAGE analysis, clearly demonstrating that this process can stably extract phycocyanin and is not affected by extraction solvent, temperature, etc. The stability of the extracted phycocyanin was also confirmed by comparing its DPPH (ɑ,ɑ-diphenyl-ß-picrylhydrazyl) scavenging activity, showing 83% removal of oxygen free radicals. This activity was about 15% higher than that of commercially available standard phycocyanin, which implies that the combined extraction method can yield relatively intact chromoprotein through absence of degradation. The results were achieved because the low temperature and high pressure extraction effectively disrupted the cell membrane of Spirulina platensis and degraded less the polypeptide subunits of phycocyanin (which is a temperature/pH-sensitive chromoprotein) as well as increasing the extraction yield. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the change in biomechanical milieu following removal of pedicle screws in instrumented single level lumbar arthrodesis. Using a validated finite element (FE) model of the intact lumbar spine (L2–5), two scenarios of L3–4 lumbar fusion were simulated: posterolateral fusion (PLF) at L3–4 using pedicle screws (PLF with pedicle screws; WiP) and L3–4 lumbar posterolateral fusion state after removal of pedicle screws (PLF without pedicle screws; WoP). The WiP model had greater range of motion (ROM) at each adjacent segment than the WoP model. This phenomenon became pronounced at the proximal adjacent segment under flexion moment. Similarly, removal of pedicle screws (the WoP model) relieved the maximal von Mises stress at adjacent segments under 4 moments compared to the WiP model. This study demonstrated that removal of pedicle screws could decrease stiffness of fusion segments, which would reduce the disk stress of adjacent segments. [ABSTRACT FROM AUTHOR]

Few studies have shown the relationship between the curve pattern and nerve root symptoms in degenerative lumbar scoliosis, and its mechanism remains unclear. We developed a finite element model of two patterns of scoliotic curves (isolated lateral bending curve, lateral bending combined with rotation curve). The stress on the nerve root was calculated on both sides (right and left) of the apex vertebra. In the lateral bending curves without rotation, the compressive nerve root stress on the concave side was greater than the tensile stress on the convex side at the apex vertebra. In contrast, when the segmental rotation of the vertebrae was added to the lateral bending curve, there was significantly higher tensile stress on the convex side, and lower compressive stress on the concave side. To conclude, rotatory listhesis may be an important pathomechanism in the development of neurologic symptoms on the convex side of the curve. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Cervical Foraminal and Discal Height after Dynamic Rotational Plating in the Cervical Discectomy and Fusion" is presented that was published in the 2013 issue of the periodical.