How does long thoracolumbar realignment surgery of adult spinal kyphotic deformity affect lower extremity compensation? Using full body radiograph.

PURPOSE: By using full body radiograph, the aim of the current study was to elucidate the expected degree of lower extremity compensatory change after long thoracolumbar realignment surgery with adult spinal deformity patient who had normal or only mild osteoarthritis on lower extremities. METHODS: Two novel parameters were used for assessment of regional compensation of the lower extremity. The Pearson correlation test was used to assess the correlation of postoperative changes of lower extremity compensation with the other spinopelvic parameters. RESULTS: Overall, 113 spinal deformity patients (mean age was 54.5 years) were recruited and the average number of fused vertebrae was 13.3 ± 3.5. Except pelvic tilt (PT), postoperative sacrum-femur angle (SF) changes showed only moderate correlation with all angular spinopelvic parameters (r = 0.323-0.374; p < .001 to p = .001). Also C7 sagittal vertical axis showed no significant correlation with SF (p = .584-.621). However, postoperative changes of sagittal femur-tibia angle (SFT) reported strong correlation with all parameters evaluated (r = 0.455-0.586; p < .001 to p = .046). CONCLUSION: For adult spinal deformity patients who had normal or only mild osteoarthritis on the lower extremities underwent long thoracolumbar realignment surgery, the surgeon could expect improvement of compensatory change of the knee with correction of spinopelvic parameters. However, the degree of hip compensation improvement was relatively difficult to predict than that of the knee, except PT.

Novel radiographic parameters for the assessment of total body sagittal alignment in adult spinal deformity patients.

OBJECTIVE: In this study, the authors' goal was to develop and validate novel radiographic parameters that better describe total body sagittal alignment (TBSA). METHODS: One hundred sixty-six consecutive operative spinal deformity patients were evaluated using full-body stereoradiographic imaging. Seven TBSA parameters were measured and then correlated to 6 commonly used spinopelvic measurements. TBSA measures consisted of 4 distance measures relating the cranial center of mass (CCOM) to the sacrum, hips, knees, and ankles, and 3 angular measures relating the CCOM to the hips, knees, and ankles. Furthermore, each TBSA parameter was correlated to patient-reported outcome (PRO) scores using the Oswestry Disability Index (ODI) and Scoliosis Research Society-22 (SRS-22) instruments. Thirty patients were randomly selected for inter- and intraobserver reliability testing of the TBSA parameters using intraclass correlation coefficients (ICCs). RESULTS: All TBSA radiographic parameters demonstrated strong linear correlation with the currently accepted primary measure of sagittal balance, the C7 sagittal vertical axis (r = 0.55-0.96, p < 0.001). Moreover, 5 of 7 TBSA measures correlated strongly with ODI and SRS-22 total scores (r = 0.42-0.51, p < 0.001). Inter- and intraobserver reliability for all TBSA measures was good to excellent (interrater ICC = 0.70-0.98, intrarater ICC = 0.77-1.0). CONCLUSIONS: In spine deformity patients, novel TBSA radiographic parameters correlated well with PROs and with currently utilized spinal sagittal measurements. Inter- and intrarater reliability was high for these novel parameters. This is the first study to propose a reliable method for measuring head-to-toe global spinal alignment.

Relationship between facet joint tropism and degeneration of facet joints and intervertebral discs based on a histological study.

PURPOSE: Evaluate the correlation between lumbar facet joint tropism, lumbar facet joint degeneration, and intervertebral disc degeneration. METHODS: Forty-two of facet joints were evaluated histologically and radiologically. RESULTS: The correlation between facet joint tropism and histologic, CT, and MRI grading was -0.159 (P = 0.339), 0.025 (P = 0.226) and -0.270 (P = 0.102), respectively. The correlation between facet joint tropism and intervertebral disc MRI grading was 0.346 (P = 0.033), and that between facet joint and intervertebral disc MRI grading was 0.208 (P = 0.210). CONCLUSIONS: Facet joint tropism was correlated with intervertebral disc degeneration but not with facet joint degeneration.

The recovery of damaged paraspinal muscles by posterior surgical treatment for patients with lumbar degenerative diseases and its clinical consequence.

BACKGROUND: Posterior lumbar surgery can lead to damage on paraspinal muscles. OBJECTIVE: Our study aimed to examine the recovery in the denervated paraspinal muscles by posterior lumbar surgery and to determine that of improvement in the lower back pain (LBP). METHODS: Depending on surgical treatments, the patients were divided into two groups: The group I (interspinous implantation with decompression) and II (posterior lumbar interbody fusion with decompression). The paraspinal mapping score was recorded for individual muscle. RESULTS: In the group I, there was reinnervation in the denervated multifidus and erector spinae at the upper, surgical and lower levels at 12 months. In the group II, there was reinnervation in the denervated erector spinae at the upper, surgical and lower levels at 12 months. There was significant aggravation in the LBP in both groups at immediate postoperative. But there was significant improvement in it at 6 months in the group I and at 12 months in the group II. CONCLUSION: There was reinnervation in not only denervated multifidus and erector spinae at 12 months following interspinous ligament stabilization but also in denervated erector spinae at 12 months following pedicle screw fixation with fusion.

Pedicle screw fixation and posterior fusion for lumbar degenerative diseases: effects on individual paraspinal muscles and lower back pain; a single-center, prospective study.

BACKGROUND: To the best of our knowledge, there have been no reports on the points at which the denervated multifidus and erector spinae muscles become reinnervated after pedicle screw fixation and posterior fusion in patients with lumbar degenerative diseases. Our study was designed to confirm reinnervation of denervated paraspinal muscles following pedicle screw fixation and posterior fusion and to confirm alleviation of the patients' lower back pain (LBP). METHODS: In this prospective study, we enrolled 67 patients who had undergone pedicle screw fixation and posterior fusion. The surgery had alleviated their leg pain, but the patients complained of LBP at the L3-5 level 3 months after the surgery. The patients were divided into two groups (I and II) according to the level at which pain was experienced. Paraspinal mapping scores were recorded preoperatively and 3, 6, 12, and 18 months postoperatively. Oswestry Disability Index and visual analogue scale scores were determined. Regression analyses using a general linear model and a mixed model were performed. RESULTS: Pedicle screw fixation and posterior fusion significantly denervated the multifidus and erector spinae not only in the surgical segment, but also in adjacent segments. Group I patients displayed reinnervation in the denervated erector spinae and multifidus muscles at 12 and 18 months, respectively. In contrast, group II showed reinnervation only in of the denervated erector spinae of the upper segment at 18 months, with no other areas of reinnervation. Postoperative LBP was significantly diminished at 12 months in group I and at 18 months in group II. There was also significantly less LBP at 6 months (prior to reinnervation of the paraspinal muscles). CONCLUSIONS: The denervated multifidus and erector spinae muscles at L4-5, which had been denervated using pedicle screw fixation and posterior fusion, were significantly reinnervated at 18 months postoperatively, whereas patients with denervation at L3-5 had only a tendency to be reinnervated at follow-up. Postoperative LBP in these patients was significantly diminished at the follow-up visits.

A minimally invasive posterior lumbar interbody fusion using percutaneous long arm pedicle screw system for degenerative lumbar disease.

The aim of this study is to evaluate the therapeutic efficacy of patients with lumbar degeneration and instability treated with percutaneous pedicle screw fixation and minimally invasive lumbar interbody fusion. Twenty-one patients were selected in our hospital from November, 2012 to March, 2013. The patients with an average age 55.62 years, including 8 vertebral spondylolisthesis, 4 lumbar intervertebral disc herniation, and 9 lumbar spinal canal stenosis cases. All the patients were managed to take the lumbar MRI and radiographs. The comparison of preoperative and postoperative (3 days, 2 weeks, 3 months) VAS and ODI score were analyzed. The results indicated that VAS scores were 7.14 ± 0.79 before operation, and 5.19 ± 0.81 in 3 days after operation, 4 ± 0.84 after 2 weeks, and 2.67 ± 0.66 after 3 months. The pain was relieved, and the postoperative VAS score was lower than that before treatment (P < 0.05). ODI score was 55.8 ± 11.4 before operation, 47.38 ± 9.38 after 3 days, 41.38 ± 8.09 after 2 weeks, 35.76 ± 4.50 after 3 months. ODI score was obviously decreased (P < 0.05). In conclusion, percutaneous pedicle screw fixation combined with minimally invasive interbody fusion is a safe, effective, feasible minimally invasive spine operation, with worthy for spreading.

Potential of fortified fibrin/hyaluronic acid composite gel as a cell delivery vehicle for chondrocytes.

Numerous treatment methods have been applied for use in cartilage repair, including abrasion, drilling, and microfracture. Although chondrocyte transplantation is the preferred treatment, it has some shortcomings, such as difficulty of application (large and posterior condylar regions), poor chondrocyte distribution, and potential cell leakage from the defect region. The cell delivery system of the tissue engineering technique can be used to overcome these shortcomings. We chose fibrin/hyaluronan (HA) composite gel as an effective cell delivery system to resolve these issues. Both components are derived from natural extracellular matrix. In the first trial, fortified fibrin/HA composite gels with rabbit chondrocytes were tested by implantation in nude mice. At 4 weeks, glycosaminoglycan contents in the fibrin/HA composite (0.186 +/- 0.006 mg/mg) were significantly higher than those in the presence of fibrin alone (0.153 +/- 0.017 mg/mg). As a next step, we applied the fibrin/HA composite gel to animal cartilage defects using full thickness cartilage defect rabbit models. The fibrin/HA composite gel with rabbit chondrocytes (allogenic) was implanted into the experimental group, and the control group was implanted with the fibrin/HA composite gel alone. Implanted chondrocytes with the fibrin/HA composite showed improved cartilage formation. In conclusion, the key to successful regeneration of cartilage is to provide the repair site with a sufficient supply of chondrogenic cells with a suitable delivery vehicle to ensure maximal differentiation and deposition of the proper extracellular matrix. This study suggests the feasibility of tissue-engineered cartilage formation using fibrin/HA composite gel.

Collagenous fibril texture of the discoid lateral meniscus.

PURPOSE: To provide the theoretic basis for treatment and to increase the understanding of the tear patterns of the discoid meniscus, we observed the collagen orientation of the discoid meniscus. METHODS: Ten meniscus specimens were used to observe the collagen fibril orientation of the complete type of the discoid lateral menisci. The samples were observed layer by layer under a polarizing filter microscope by using Sirius red staining, and they were also observed under a scanning electron microscope. RESULTS: The lateral discoid meniscus is classified into 7 layers based on collagen fibril orientation. The femoral surface of the discoid meniscus is covered by dense and well-arranged thick fibrils, which very much resembles a bunched streak. The fibrils show a sagittal isotropic-arranged orientation. However, the tibial surface shows an irregular and anisotropically arranged orientation. In the outer layer, a meshwork of thin fibrils has been observed. The collagen fibrils in the inner layer are radially orientated from the lateral side to the medial side. In the central layer, the peripheral collagen fibrils are displayed as dense bundles running in a circumferential pattern, whereas its medial zone shows as thin, loosely, and irregularly arranged fibrils without a bundle formation. The anterior and posterior zones of the central layer show the collagen fibrils with a straight arrangement in the radial direction. CONCLUSIONS: In the lateral middle zone of discoid meniscus, the collagen fibrils run parallel to the periphery of the meniscus. Therefore, it would be ideally suited for resisting hoop stresses. From this anatomic study, it is apparent that the peripheral portion of the meniscus is constructed to bear a load. CLINICAL RELEVANCE: It is strongly recommended that the peripheral portion of the discoid meniscus should be preserved when a resection of the meniscus is mandatory.

Preconditioning of mesenchymal stem cells with low-intensity ultrasound for cartilage formation in vivo.

The purpose of this study was to evaluate the benefits of in vitro preconditioning of mesenchymal stem cells (MSCs) using low-intensity ultrasound (US) in the induction of chondrogenic differentiation of MSCs in vivo. After rabbit bone marrow-derived MSCs were seeded onto a polyglycolic acid (PGA) scaffold, the PGA-MSCs constructs were divided into 4 subgroups: untreated control, low-intensity US group, transforming growth factor-beta [TGF]-treated group and low-intensity US/TGF group. The chondrocyte-seeded PGA construct served as a positive control. For 1 week before implantation, the low-intensity US groups were subjected to ultrasound treatment for 20 min daily at an intensity of 200 mW/cm(2). The TGF groups were treated with 10 ng/mL TGF-beta1. The cells were then implanted into the nude mouse subcutaneously. Retrieved 1, 2, 4, and 6 weeks after implantation, each construct underwent gross examination, histology, biochemical assays, mechanical testing, and reverse transcriptase polymerase chain reaction (RT-PCR). Substantial size reduction and blood invasion were found much earlier in the groups that did not undergo low-intensity US than in those that did. Safranin O/Fast green staining revealed that the chondrogenic differentiation of MSCs was more widespread throughout the constructs in the low-intensity US groups. In the biochemical and mechanical analyses, the low-intensity US and low-intensity US/TGF groups were significantly better in forming hyaline cartilage-like tissue by 4 weeks than the non-low-intensity US groups. Presented by von Kossa staining, the development of osteogenic phenotypes was highly suppressed until 4 weeks in the low-intensity US groups, along with compressive strength comparable to the positive control. In the RT-PCR analysis before implantation, the messenger RNA levels of Sox-9, aggrecan, and tissue inhibitors of metalloproteinase-2 were higher in the low-intensity US groups, while those of type I and type X collagens and matrix metalloproteinase-13 were higher in the non-low-intensity US groups. Blood invasion into the constructs was also considerably hindered in the low-intensity US groups. These results strongly indicate that low-intensity US preconditioning in vitro could be an effective cue to upregulate chondrogenic differentiation of MSCs in vivo.

Effects of low-intensity ultrasound on chondrogenic differentiation of mesenchymal stem cells embedded in polyglycolic acid: an in vivo study.

In this study we investigated the effects of LIUS on chondrogenic differentiation of bone marrow-derived mesenchymal stem cells (BM-MSC). Our hypothesis is that LIUS may be a noninvasively effective stimulant to a biological system in vivo by turning on differentiation of MSCs and promotion of chondrogenesis. MSCs were isolated from the bone marrow of New Zealand white rabbits and cultured in monolayer for 2 weeks. They were then harvested and seeded into polyglycolic acid (PGA) non-woven mesh at a number of 5 x 10(6) cells. Cultured with a chondrogenic-defined media for 1 week, the PGA/MSCs constructs (n = 4) were implanted subcutaneously in the back of nude mice (n = 9, each group). The ultrasound (US) group received US stimulation at a frequency of 0.8 MHz and intensity of 200 mW/cm(2) for 10 min every day up to 4 weeks, while the control group had no US stimulation. Analyses of histological, immunohistochemical, biochemical, and mechanical characteristics were made at 1, 2, and 4 weeks post-stimulation, respectively. Total DNA contents showed no significant difference between the two groups. Total collagen and glycosaminoglycan (GAG) increased more significantly in the US-stimulated group than in the control. Histology of Safranin O/Fast green confirmed more intense and spreading extracellular matrix (ECM) at 2 and 4 weeks in the US-stimulated specimens. Mechanical tests exhibited that compressive strengths were also significantly higher in the US-stimulated cells at later times. This study strongly suggests that it may be possible for ultrasound to have some stimulatory effects in vivo on the chondrogenesis of MSCs.

The effect of sonication on simulated osteoarthritis. Part II: alleviation of osteoarthritis pathogenesis by 1 MHz ultrasound with simultaneous hyaluronate injection.

In our previous study, we demonstrated the effects of ultrasound (US) on the delivery of hyaluronan (HA) into the synovium, even at molecular sizes as high as 3000 kDA. We hypothesized that a combined therapy with US and HA would have synergistic effects on alleviating the pathogenesis of osteoarthritis (OA). In the present study, we evaluated the effectiveness of sonication on the progress of induced OA in rabbits. We measured the cartilage degradation and inflammation, synovial fluid amount along with protein content and, finally, performed histologic analyses of the integrity of the cartilage and synovium. Low-intensity continuous US at 1 MHz, 400 mW/cm2 was applied to the knees for 10 min bid. Combined treatment with US and HA most strikingly reduced total synovial fluid volume and also significantly alleviated the OA-induced accretion of total protein, proteoglycan and prostaglandin E2 in the synovial fluid. It also attenuated the release of collagen type II and matrix metalloproteinase-3 in the OA-induced joint to normal levels. Histopathology revealed that combined HA and US treatment also reduced the severity of OA-induced structural damages in the cartilage and synovium. The effectiveness of HA with regard to the alleviation of OA pathogenic changes can be greatly enhanced by the simultaneous treatment with HA and US.