Chang Jung Chiang

Extracorporeal shockwave therapy improves short-term functional outcomes of shoulder adhesive capsulitis

BACKGROUND The treatment of adhesive capsulitis is a dilemma for orthopaedic rehabilitation specialists. In this study, we assessed whether extracorporeal shockwave therapy (ESWT) improves the functional outcome of primary shoulder adhesive capsulitis. METHODS In this prospective, randomized, controlled, single-blind clinical trial, we enrolled 40 patients with primary adhesive capsulitis to assess whether ESWT can improve the functional outcome of primary adhesive capsulitis better than oral steroid therapy. Patients were allocated to the oral steroid group or ESWT group with randomization. Functional outcome evaluations were performed using the Constant Shoulder Score (CSS) and Oxford Shoulder Score. RESULTS Both groups showed significant improvement in the Oxford Shoulder Score evaluation throughout the study period. In the ESWT group, the total CSS and range of motion (ROM) parameter of the CSS in the ESWT group showed significant improvement from the fourth week that was better than that in the steroid group; the activities–of–daily living (ADL) parameter of the CSS achieved significance and was better than that in the steroid group at the sixth week. For the steroid group, pain was significantly reduced from baseline to the fourth week of the study; ADL and ROM improved at the fourth to 12th week. For the ESWT group, ADL and ROM improvements were significant from baseline to the sixth week. CONCLUSION Our results showed that ESWT can be an alternative treatment, at least in the short-term, for primary adhesive capsulitis of the shoulder. In addition, all of the side effects of ESWT were transient and tolerable.

Isoflavones prevent bone loss following ovariectomy in young adult rats

Soy protein, a rich source of phytoestrogens, exhibit estrogen-type bioactivity. The purpose of this study was to determine if ingestion of isoflavones before ovariectomy can prevent bone loss following ovariectomy. Twenty-four nulliparous Wistar rats were randomly divided into four groups. In the normal diet groups, a sham operation was performed on Group A, while ovariectomy was performed on Group B. For Groups C and D, all rats were fed with an isoflavone-rich (25 mg/day) diet for one month, then bilateral ovariectomy were performed. In the rats in Group C, a normal diet was begun following the ovariectomy. The rats in Groups D continued to receive the isoflavone-rich diet for two additional months postoperatively. All rats were sacrificed 60 days after surgery. The weight of bone ash of the long bones and whole lumbar spine were determined. A histological study of cancellous bone was done and biochemical indices of skeletal metabolism were performed and analyzed. The markers of bone metabolism exhibited no significant changes. When compared with the sham-operated rats fed a normal diet, the bone mass of ovariectomized rats decreased significantly; pre-ovariectomy ingestion of an isoflavone-rich diet did not prevent bone loss. The bone mass of rats treated with an isoflavone-rich diet for three months was higher than controls two months after ovariectomy.Dietary isoflavones did not prevent the development of post-ovariectomy bone loss, but long-term ingestion of an isoflavone-rich diet increased the bone mineral contents after ovariectomy in young rats.

Retaining intradiscal pressure after annulotomy by different annular suture techniques, and their biomechanical evaluations

BACKGROUND The adverse effects of annulotomy during lumbar discectomy have been increasingly recognized, and methods are developing to repair the annular defect. Biomechanically, the repair should retain the intra-nuclear pressure, which is doubtful using the current suture techniques. Therefore, a new suture technique was designed and tested to close a simpler type of annular incision. METHODS A new suture technique, the modified purse-string suture, was introduced into a re-validated nonlinear finite element human disk model after creating a standard transverse slit incision, as well as two other suture techniques: either two simple sutures, or a horizontal crossed suture, and compared their contact pressure on the cleft contact surface. Then, porcine lumbar endplate-disk-endplate complexes with transverse slit incisions were repaired using the three techniques. Quantitative discomanometry was then applied to compare their leakage pressure, as a parameter of disk integrity. FINDINGS In finite element model, the new technique created the greatest contact pressure along the suture range (the outer annulus), and generated a minimum contact pressure at the critical point, which was 68% and 55% higher than the other two suture techniques. In quantitative discomanometry, the new suture technique also had an average leakage pressure of 85% and 49% higher than the other two suture techniques. INTERPRETATION The modified purse-string suture can generate higher contact pressure than the other two techniques at finite element analysis and in realistic animal models, which aids in retaining intra-discal pressure, and should be encouraged in clinical practice.

Pharmacokinetics of di-isononyl phthalate in freely moving rats by UPLC–MS/MS

Di-isononyl phthalate (DINP) is a general-purpose plasticizer for polyvinyl chloride. However, this industrial chemical plasticizer used as a clouding agent has recently contaminated food and beverages that had been inspected by Taiwan Food and Drug Administration. This study develops a sensitive and specific method combining ultra-performance liquid chromatography with electrospray ionization tandem mass spectrometry (UPLC-MS/MS) to investigate the pharmacokinetics of DINP in freely moving rats. Multiple reaction monitoring (MRM) was used to monitor the transition of the protonated molecule m/z of 419 [M+H](+) to the product ion 149 for DINP. The analyte was analyzed by UPLC-MS/MS with C18 column (100×2.1mm, 1.7 μm) which was equilibrated and eluted with an isocratic mixture of acetonitrile-ammonium acetate water solution (90:10, v/v) at a flow rate of 0.3 mL/min. Linear calibration curves were obtained for DINP concentration ranges of 0.05-2.5 μg/mL in plasma and feces. The feces were homogenized mechanically using 50% acetonitrile as the medium. The pharmacokinetic curve demonstrates that the disposition of DINP in rat plasma was fitted well by the two-compartment model after DINP administration (10 mg/kg, i.v.). The elimination half-life of DINP was 364±146 min and 150±58 min for intravenous (10 mg/kg) and oral (100 mg/kg) administration, respectively. The pharmacokinetic data indicate that the oral bioavailability of DINP in freely moving rats was about 1.19%. The total DINP excretion up to 48 h was 13.64±3.99% in feces.

Isokinetic eccentric exercise can induce skeletal muscle injury within the physiologic excursion of muscle-tendon unit: a rabbit model

Background and PurposeIntensive eccentric exercise can cause muscle damage. We simulated an animal model of isokinetic eccentric exercise by repetitively stretching stimulated triceps surae muscle-tendon units to determine if such exercise affects the mechanical properties of the unit within its physiologic excursion.MethodsBiomechanical parameters of the muscle-tendon unit were monitored during isokinetic eccentric loading in 12 rabbits. In each animal, one limb (control group) was stretched until failure. The other limb (study group) was first subjected to isokinetic and eccentric cyclic loading at the rate of 10.0 cm/min to 112% (group I) or 120% (group II) of its initial length for 1 hour and then stretched to failure. Load-deformation curves and biomechanical parameters were compared between the study and control groups.ResultsWhen the muscle-tendon unit received eccentric cyclic loading to 112%, changes in all biomechanical parameters – except for the slope of the load-deformation curve – were not significant. In contrast, most parameters, including the slope of the load-deformation curve, peak load, deformation at peak load, total energy absorption, and energy absorption before peak load, significantly decreased after isokinetic eccentric cyclic loading to 120%.ConclusionWe found a threshold for eccentrically induced injury of the rabbit triceps surae muscle at between 12% and 20% strain, which is within the physiologic excursion of the muscle-tendon units. Our study provided evidence that eccentric exercise may induce changes in the biomechanical properties of skeletal muscles, even within the physiologic range of the excursion of the muscle-tendon unit.

Time course investigation of intervertebral disc degeneration in a rat-tail puncture model.

AIMS Intervertebral disc (IVD) degeneration was believed to contribute to lower back pain. The aim of the study was to investigate the pathogenesis and regulatory mechanism of puncture-induced IVD degeneration. MAIN METHODS We established a rat-tail puncture model using Kirschner wire and a homemade stopper. The progress of disc degeneration was evaluated by histological examination and the quantitative measurement of type I, type II collagen and other factors expression at 0.5, 1, 2, 6, and 12weeks after puncture and was compared with control rats of the same age. KEY FINDINGS Histological examination and Safranin-O staining revealed progressive degeneration of the punctured disc. Matrix metalloproteinase 13 (MMP13) was increased at 1week after puncture but did not change in the control group. The interleukin-1 beta (IL-1β) mRNA expression level was elevated at the acute stage after puncture compared with the control group. The hypoxia inducible factor 2 (HIF-2) increased expression in punctured groups. Additionally, compare to adjacent non-punctured segments, HIF-2α expression level transiently increased and then decreased in the nucleus pulposus immediately following puncture, and it then increased 12weeks after puncture. SIGNIFICANCE The degenerative changes observed in this rat-tail puncture model are similar to human disc degeneration and that this model may be valuable for elucidating the molecular mechanisms and pathways underlying disc degeneration.

In vivo evaluation of a new biphasic calcium phosphate bone substitute in rabbit femur defects model

Calcium phosphate ceramic has been known for its properties of bioactivity and osteoconductivity and has been widely used in orthopedic, plastic and craniofacial surgeries. The biocompatibility, unlimited availability, lower morbidity for the patient and cost-effectiveness of calcium phosphate ceramics represent important advantages over other biological bone graft, such as autografts and allografts. A new synthetic biphasic calcium phosphate (BCP), Bicera™ (60% HA and 40% β-TCP), is manufactured by Wiltrom Co., Ltd., as a new bone graft substitute. It shows good biocompatibility without cytotoxicity in in vitro test. To evaluate the possible application for clinical use, we used New Zealand white rabbit femur defect model to compare the osteoconductivity of this new bone substitute to another commercially available bone substitute (Triosite®) which was used as the control material. According to the macroscopic observation, both bone substitutes show good biocompatibility and no abnormal inflammation either infection was seen at the implantation sites. X-rays image of implant sites at one month, three months and six months showed all implanted materials were well incorporated with host bone. All of them were not fully absorbed and replaced after six months implantation. In the histological and hitomorphometric data, new bone grew into the surface of the peripheral pores in both bone substitutes and increased over time. Moreover, the degree of bone regeneration appeared to be relatively greater in the specimens with Bicera™ when compared with Triosite®. We concluded that this new synthetic BCP (Bicera™) showed similar biocompatibility and osteoconductive characteristic comparing with commercial product Triosite® in rabbit femur defects model.

Removal of fixation construct could mitigate adjacent segment stress after lumbosacral fusion: A finite element analysis

Background data: Combined usage of posterior lumbar interbody fusion and transpedicular fixation has been extensively used to treat the various lumbar degenerative disc diseases. The transpedicular fixator aims to increase stability and enhance the fusion rate. However, how the fused disc and bridged vertebrae respectively affect adjacent‐segment diseases progression is not yet clear. Methods: Using a validated lumbosacral finite‐element model, three variations at the L4–L5 segment were analyzed: 1) moderate disc degeneration, 2) instrumented with a stand‐alone cage and pedicle screw fixators, and 3) with the cage only after fusion. The intersegmental angles, disc stresses, and facet loads were examined. Four motion tests, flexion, extension, bending, and twisting, were also simulated. Findings: The adjacent‐segment disease was more severe at the cephalic segment than the caudal segment. After solid fusion and fixation, the increase in intersegmental angles, disc stresses and facet loads of the adjacent segments were about 57.6%, 47.3%, and 59.6%, respectively. However, these changes were reduced to 30.1%, 22.7%, and 27.0% after removal of the fixators. This was attributed to the differences between the biomechanical characteristics of the fusion and fixation mechanisms. Interpretation: Fixation superimposes a stiffer constraint on the mobility of the bridged segment than fusion. The current study suggested that the removal of spinal fixators after complete fusion could decrease the stress at adjacent segments. Through a minimally invasive procedure, we could reduce secondary damage to the paraspinal structures while removing the fixators, which is of utmost concern to surgeons. HighlightsThe rigidity‐raising effect in instrumented segment induces adjacent segmental degeneration.The intersegmental angles, disc stress, and facet loads are higher in caudal segments.The compensations at adjacent segments could be decreased after removal of spinal fixators.Remove spinal fixators after fusion might mitigate the progression of adjacent segment disease.

Percutaneous pedicle screw placement under single dimensional fluoroscopy with a designed pedicle finder—a technical note and case series

BACKGROUND CONTEXT Minimally invasive spine surgery has become increasingly popular in clinical practice, and it offers patients the potential benefits of reduced blood loss, wound pain, and infection risk, and it also diminishes the loss of working time and length of hospital stay. However, surgeons require more intraoperative fluoroscopy and ionizing radiation exposure during minimally invasive spine surgery for localization, especially for guidance in instrumentation placement. In addition, computer navigation is not accessible in some facility-limited institutions. PURPOSE This study aimed to demonstrate a method for percutaneous screws placement using only the anterior-posterior (AP) trajectory of intraoperative fluoroscopy. STUDY DESIGN A technical report (a retrospective and prospective case series) was carried out. PATIENT SAMPLE Patients who received posterior fixation with percutaneous pedicle screws for thoracolumbar degenerative disease or trauma comprised the patient sample. METHOD We retrospectively reviewed the charts of consecutive 670 patients who received 4,072 pedicle screws between December 2010 and August 2015. Another case series study was conducted prospectively in three additional hospitals, and 88 consecutive patients with 413 pedicle screws were enrolled from February 2014 to July 2016. The fluoroscopy shot number and radiation dose were recorded. In the prospective study, 78 patients with 371 screws received computed tomography at 3 months postoperatively to evaluate the fusion condition and screw positions. RESULTS In the retrospective series, the placement of a percutaneous screw required 5.1 shots (2-14, standard deviation [SD]=2.366) of AP fluoroscopy. One screw was revised because of a medialwall breach of the pedicle. In the prospective series, 5.8 shots (2-16, SD=2.669) were required forone percutaneous pedicle screw placement. There were two screws with a Grade 1 breach (8.6%), both at the lateral wall of the pedicle, out of 23 screws placed at the thoracic spine at T9-T12. Forthe lumbar and sacral areas, there were 15 Grade 1 breaches (4.3%), 1 Grade 2 breach (0.3%), and 1 Grade 3 breach (0.3%). No revision surgery was necessary. CONCLUSION This method avoids lateral shots of fluoroscopy during screw placement and thus decreases the operation time and exposes surgeons to less radiation. At the same time, compared with the computer-navigated procedure, it is less facility-demanding, and provides satisfactory reliability and accuracy.

Literature Review and Meta-analysis of Transcutaneous Electrical Nerve Stimulation in Treating Chronic Back Pain

Background and Objectives This study is a meta-analysis of randomized controlled trials comparing the efficacy of transcutaneous electrical nerve stimulation (TENS) to a control and to other nerve stimulation therapies (NSTs) for the treatment of chronic back pain. Methods Citations were identified in MEDLINE, the Cochrane Library, Google Scholar, and ClinicalTrials.gov through June 2014 using the following keywords: nerve stimulation therapy, transcutaneous electrical nerve stimulation, back pain, chronic pain. Control treatments included sham, placebo, or medication only. Other NSTs included electroacupuncture, percutaneous electrical nerve stimulation, and percutaneous neuromodulation therapy. Results Twelve randomized controlled trials including 700 patients were included in the analysis. The efficacy of TENS was similar to that of control treatment for providing pain relief (standardized difference in means [SDM] = −0.20; 95% confidence interval [CI], −0.58 to 0.18; P = 0.293). Other types of NSTs were more effective than TENS in providing pain relief (SDM = 0.86; 95% CI, 0.15–1.57; P = 0.017). Transcutaneous electrical nerve stimulation was more effective than control treatment in improving functional disability only in patients with follow-up of less than 6 weeks (SDM = −1.24; 95% CI, −1.83 to −0.65; P < 0.001). There was no difference in functional disability outcomes between TENS and other NSTs. Conclusions These results suggest that TENS does not improve symptoms of lower back pain, but may offer short-term improvement of functional disability.