The impact of novel inflammation-preserving treatment towards lumbar disc herniation resorption in symptomatic patients: a prospective, multi-imaging and clinical outcomes study

PURPOSE

We performed a prospective one-year multi-imaging study to assess the clinical outcomes and rate of disc resorption in acute lumbar disc herniation (LDH) patients undergoing inflammation-preserving treatment (i.e. no NSAIDS, steroids).

METHODS

All patients received gabapentin to relieve leg pain, 12 sessions of acupuncture. Repeat MRI was performed, every 3 months, after 12 sessions of treatment continued for those without 40% reduction in herniated disc sagittal area. Disc herniations sizes were measured on sagittal T2W MRI sequences, pre-treatment and at post-treatment intervals. Patients were stratified to fast, medium, slow, and prolonged recovery groups in relation to symptom resolution and disc resorption.

RESULTS

Ninety patients (51% females; mean age: 48.6 years) were assessed. Mean size of disc herniation was 119.54 ± 54.34 mm2, and the mean VAS-Leg score was 6.12 ± 1.13 at initial presentation. A total of 19 patients (21.1%) improved at the time of the repeat MRI (i.e. within first 3 months post-treatment). 100% of all patient had LDH resorption within one year (mean: 4.4. months). There was no significant difference at baseline LDH between fast, medium, slow, and prolonged resorption groups. Initial LDH size was weakly associated with degree of leg pain at baseline and initial gabapentin levels. Surgery was avoided in all cases.

CONCLUSION

This is the first study to note inflammation-preserving treatment, without conventional anti-inflammatory and steroid medications, as safe and effective for patients with an acute LDH. Rate of disc resorption (100%) was higher than comparative recent meta-analysis findings (66.7%) and no patient underwent surgery.

A 3D Finite Element Analysis of biomechanical effects on teeth and bone during true intrusion of posteriors using miniscrews

OBJECTIVE

The primary objective of this study was to investigate the biomechanical effects and stresses on bone, PDL, cementum and displacement along X-,Y- and Z-axis during true intrusion of molars using mini-implants with finite element analysis; the secondary objective of the study was to find out the best method for posterior intrusion in clinical practice.

MATERIAL AND METHODS

A 3D finite element method was used to simulate true molar intrusion using sliding mechanics. Two groups were made, with mini-implants placed on buccal side and palatal side with a cap splint for MODEL1, and a single mini-implant placed buccally with transpalatal arch (TPA) for MODEL2. The material characteristics which include the Young's modulus and Poison's ratio were assigned. von Mises stress, principal stress on PDL and alveolar bone, displacements in all the 3 planes were determined.

RESULTS

Bone stress patterns showed compressive stresses on the buccal aspect and tensile stresses on the palatal aspect for both MODELS. Stresses in the PDL and cementum were mainly concentrated in the apex region, with a more uniform distribution of stresses for MODEL 1. Tooth displacement showed true intrusion for both MODELS, i.e. the Z axis, and a more controlled buccal tipping for MODEL 1.

CONCLUSION

Of the modalities compared, the best controlled tooth movements for posterior intrusion in the treatment of open bite were obtained with mini-implants placed with a cap splint (MODEL 1).

LOX, but not LOXL2, promotes bone metastasis formation and bone destruction in triple-negative breast cancer

The primary function of the lysyl oxidase (LOX) family, including LOX and its paralogue LOX-like (LOXL)-2, is to catalyze the covalent crosslinking of collagen and elastin in the extracellular matrix. LOX and LOXL2 are also facilitating breast cancer invasion and metastatic spread to visceral organs (lungs, liver) in vivo. Conversely, the contribution of LOX and LOXL2 to breast cancer bone metastasis remains scant. Here, using gene overexpression or silencing strategies, we investigated the role of LOX and LOXL2 on the formation of metastatic osteolytic lesions in animal models of triple negative breast cancer. In vivo, the extent of radiographic metastatic osteolytic lesions in animals injected with LOX-overexpressing [LOX(+)] tumor cells was 3-fold higher than that observed in animals bearing tumors silenced for LOX [LOX(-)]. By contrast, the extent of osteolytic lesions between LOXL2(+) and LOXL2(-) tumor-bearing animals did not differ, and was comparable to that observed with LOX(-) tumor-bearing animals. In situ, TRAP staining of bone tissue sections from the hind limbs of LOX(+) tumor-bearing animals was substantially increased compared to LOX(-), LOXL2(+) and LOXL2(-)-tumor-bearing animals, which was indicative of enhanced active-osteoclast resorption. In vitro, tumor-secreted LOX increased osteoclast differentiation induced by RANKL, whereas LOXL2 seemed to counteract LOX's pro-osteoclastic activity. Furthermore, LOX (but not LOXL2) overexpression in tumor cells induced a robust production of IL-6, the latter being a pro-osteoclastic cytokine. Based on these findings, we propose a model in which LOX and IL-6 secreted from tumor cells act in concert to enhance osteoclast-mediated bone resorption that, in turn, promotes metastatic bone destruction in vivo.

Cemental and alveolar bone defects after chronic exposure to amoxicillin in rats (histopathologic and radiographic study)

OBJECTIVES

This study aimed to shed new light on the potential detrimental effects on cementum and adjacent alveolar bone after chronic exposure to amoxicillin.

METHODS

Six pregnant adult Albino rats were equally divided into two groups. Saline solution and amoxicillin (100 mg/Kg) were given to rats of control and amoxicillin group, respectively from the 13th to the 21st day of pregnancy. The same treatment was given to the pups till the 42nd day. The cementum of the first molar teeth and the surrounding alveolar bone were examined qualitatively by histopathological and scanning electron microscope, and quantitatively by energy dispersive X-ray spectroscopy and cone beam computed tomography.

RESULTS

Amoxicillin group depicted cemental and alveolar bone defects along with resorption lacunae. Statistically significant decreases in calcium and calcium/phosphorus ratio in cementum and in calcium only in alveolar bone were evident (p ≤ 0.05). Overall cementum and alveolar bone densities also showed statistically significant decreases (p ≤ 0.05).

CONCLUSION

Chronic amoxicillin administration displayed destructive effects on cementum and the surrounding alveolar bone which may disturb tooth attachment integrity. Therefore, it is recommended to minimize its haphazard usage during pregnancy and early childhood.

Autophagy in an extruded disc compared to the remaining disc after lumbar disc herniation in the same patient

PURPOSE

The purpose of this study was to investigate autophagy in an extruded disc and to compare this activity with the activity in the remaining disc after lumbar disc herniation in the same patient.

METHODS

In total, 12 patients (females 4, males 8) with the extruded type of lumbar disc herniation (LDH) were surgically treated. Their mean age was 54.3 ± 15.8 years (range: 29 ~ 78 years). The mean interval from the occurrence of symptoms to the operation was 9.8 ± 9.4 weeks (range: 2 ~ 24 weeks). The extruded discs were excised, and the remaining disc material removed, to prevent recurrence of herniation. Immediately after specimen collection, all tissues were stored at -70 °C prior to analysis. Autophagy was assessed immunohistochemically and via Western blotting for Atg5, Atg7, Atg12, Atg12L1, and Beclin-1. And the relationship between autophagy and apoptosis was investigated by correlation analysis of caspase-3 with autophagy proteins.

RESULTS

The expression levels of autophagic markers were significantly increased in the extruded discs compared to the remaining discs within the same patients. The mean expression levels of Atg5, Atg7, Atg12, and Beclin-1 in extruded discs were statistically significantly higher than those in the remaining discs (P < 0.01, P < 0.001, P < 0.01, and P < 0.001 respectively).

CONCLUSIONS

The autophagic pathway was more active in extruded disc material than in remaining disc material within the same patient. This may explain spontaneous resorption of the extruded disc after LDH.

Bone Flap Resorption After Cranioplasty: Risk Factors and Proposal of the Flap Integrity Score

BACKGROUND

Bone flap resorption is a known complication of postdecompressive autologous cranioplasty. Although several potential etiopathogenetic factors have been investigated, their role is still under discussion. To further complicate things, resorption is not an all-or-nothing event, patients frequently presenting with different degrees of flap remodeling. Focus of this paper was to describe the elaboration of a score quantifying bone resorption according to a set of clinical and radiological criteria, hopefully allowing prompt identification of patients needing resurgery before the development of adverse events.

METHODS

In a 10-year period, 281 autologous cranioplasties were performed at our institution following decompressive craniectomy. Pertinent clinical and radiological information was registered. A set of 3 clinical and 3 radiological parameters was established to score the degree of resorption, identified under the acronym FIS (Flap Integrity Score). Three groups of patients emerged, respectively showing no (208), partial (32), and advanced (41) resorption.

RESULTS

An overall 14.6% incidence of advanced bone resorption was found in our series. Younger age, bone multifragmentation, higher postcranioplasty Glasgow Outcome Scale scores, <2 cm distance of medial craniectomy border from the midline, and cause leading to decompressive craniectomy were associated to a statistically significant higher risk of developing a relevant bone flap resorption. The first three variables were confirmed as risk factors in multivariate analysis. Flap Integrity Score well discriminated the 3 different groups.

CONCLUSIONS

Autologous bone repositioning is still a valuable, low-cost, cosmetically and functionally satisfactory procedure. Nonetheless, although resorption affects a minor percentage of patients, its early identification and treatment can improve long-term results.

Integration of osteoclastogenesis through addition of PBMCs in human osteochondral explants cultured ex vivo

The preservation of tissue specific cells in their native 3D extracellular matrix in bone explants provides a unique platform to study remodeling. Thus far, studies involving bone explant cultures showed a clear focus on achieving bone formation and neglected osteoclast activity and resorption. To simulate the homeostatic bone environment ex vivo, both key elements of bone remodeling need to be represented. This study aimed to assess and include osteoclastogenesis in human osteochondral explants through medium supplementation with RANKL and M-CSF and addition of peripheral blood mononuclear cells (PBMCs), providing osteoclast precursors. Osteochondral explants were freshly harvested from human femoral heads obtained from hip surgeries and cultured for 20 days in a two-compartment culture system. Osteochondral explants preserved viability and cellular abundance over the culture period, but histology demonstrated that resident osteoclasts were no longer present after 4 days of culture. Quantitative extracellular tartrate resistant acid phosphatase (TRAP) analysis confirmed depletion of osteoclast activity on day 4 even when stimulated with RANKL and M-CSF. Upon addition of PBMCs, a significant upregulation of TRAP activity was measured from day 10 onwards. Evaluation of bone loss trough μCT registration and measurement of extracellular cathepsin K activity revealed indications of enhanced resorption upon addition of PBMCs. Based on the results we suggest that an external source of osteoclast precursors, such as PBMCs, needs to be added in long-term bone explant cultures to maintain osteoclastic activity, and bone remodeling.

Involvement of the Notch signaling system in alveolar bone resorption

The Notch pathway is an evolutionarily preserved signaling pathway involved in a variety of vital cell functions. Additionally, it is one of the key regulators of inflammation, and controls the differentiation and function of different cells. Moreover, it was found to be involved in skeletal development and bone remodeling process. This review provides an overview of the involvement of the Notch signaling pathway in the pathogenesis of alveolar bone resorption in different forms of pathological conditions such as apical periodontitis, periodontal disease, and peri-implantitis. In vitro and in vivo evidence have confirmed the involvement of Notch signaling in alveolar bone homeostasis. Nonetheless, Notch signaling system, along with complex network of different biomolecules are involved in pathological process of bone resorption in apical periodontitis, periodontitis, and peri-implantitis. In this regard, there is a substantial interest to control the activity of this pathway in the treatment of disorders associated with its dysregulation. This review provides knowledge on Notch signaling and outlines its functions in alveolar bone homeostasis and alveolar bone resorption. Further investigations are needed to determine whether inhibition of the Notch signaling pathways might be beneficial and safe as a novel approach in the treatment of these pathological conditions.

Abra-ka-diskus: Vanishing Calcified Herniated Thoracic Disk

Herniated thoracic disk has an incidence of 1/1 million. Treatment options for a calcified herniated disk include conservative management or diskectomy with or without fusion. We describe a patient who presented a year ago with a 5-month history of back pain, thoracic radiculopathy, and normal physical examination. Imaging revealed a giant calcified herniated thoracic disk at T10-T11. She underwent epidural steroid injections and chiropractic manipulation. Imaging obtained at 1-year follow-up showed near-complete resorption of the calcified thoracic disk.

Evaluation of accuracy of an electronic apex locator in presence of sodium hypochlorite in primary teeth with and without resorption

This study compared the accuracy of Root ZX mini apex locator in presence of sodium hypochlorite (NaOCl) in primary molars with and without apical resorption. Sixty-four extracted primary lower molar teeth with 32 root resorption and 32 without resorption were selected. To determine the actual working length (AWL), a K-file was inserted into the root canal until the tip of the file was visible at the major foramen or the resolution level. It was then withdrawn 1 mm. This value was recorded as AWL. The teeth were then divided subgroups (with/without NaOCl). To determine the electronic working length, a Root ZX mini apex locator in canals with/without NaOCl was used. A K-file was inserted into the canal to just beyond the foramen, as indicated by the flashing "APEX" bar, and the electronic working length was determined by subtracting 1 mm from this length. The deviation of the Root ZX mini measurement from the AWL was determined. Student's t-test was used for statistical analysis. In teeth with no resorption, the measurement accuracy rates (within+/-0.5 mm) of non-NaOCl and NaOCl groups were 84.37% and 81.25%, respectively (p > 0.05); within+/-1 mm, the non-NaOCl and NaOCl demonstrated 100% and 96.87% accuracy, respectively (p > 0.05). In teeth with resorption, the measurement accuracy rates (within+/-0.5 mm) was 81.25% for the non-NaOCl and 62.50% for the NaOCl, respectively (p < 0.05). The measurement accuracy rates (within+/-1 mm) of the non-NaOCl and NaOCl was 96.87% and 84.37%, respectively (p < 0.05). The presence of NaOCl in the root canal affected the accuracy of the Root ZX mini in primary teeth with apical resorption, but not in teeth without resorption.

Changes in load distribution after unilateral condylar fracture: A finite element model study

OBJECTIVE

Premature dental contact on the fractured side and a contralateral open bite are signs of a unilaterally fractured condyle of the temporomandibular joint (TMJ). The lateral pterygoid muscle pulls the condyle inwards, causing angulation of the fractured part and shortening of the ramus. This imbalance after fracture might change the load in both TMJs and consequently induce remodeling. The present study aimed to calculate this change in load. It is hypothesized to decrease on the fractured side and increase on the non-fractured side.

DESIGN

For these calculations, a finite element model (FEM) was used. In the FEM, shortening of the ramus varied from 2 mm to 16 mm; angulation, from 6.25° to 50°.

RESULTS

After fracture, load on the non-fractured side increased, but only at maximal mouth opening (MMO). Simultaneously, load on the fractured side decreased, at both timepoints, i.e., MMO and closed mouth. When comparing all simulations at those time points, i.e., from 2 mm and 6.25° to 16 mm and 50°, the load in the fractured condyle declines steadily. However, for both timepoints, a threshold stands out around 6 mm shortening and 18.75° angulation: visualization of the fractured condyle showed, apart from load on the condylar head, a second point of load more medial in the TMJ which was most evident in the 6 mm - 18.75° simulation.

CONCLUSIONS

These findings could implicate that the balance between both TMJs is more difficult to restore after a fracture with more than 6 mm shortening and more than 18.75° angulation.

Development of a physiologically based toxicokinetic model for lead in pregnant women: The role of bone tissue in the maternal and fetal internal exposure

Epidemiological studies have shown associations between prenatal exposure to lead (Pb) and neurodevelopmental effects in young children. Prenatal exposure is generally characterized by measuring the concentration in the umbilical cord at delivery or in the maternal blood during pregnancy. To assess internal Pb exposure during prenatal life, we developed a pregnancy physiologically based pharmacokinetic (p-PBPK) model that to simulates Pb levels in blood and target tissues in the fetus, especially during critical periods for brain development. An existing Pb PBPK model was adapted to pregnant women and fetuses. Using data from literature, both the additional maternal bone remodeling, that causes Pb release into the blood, and the Pb placental transfers were estimated by Bayesian inference. Additional maternal bone remodeling was estimated to start at 21.6 weeks. Placental transfers were estimated between 4.6 and 283 L.day-1 at delivery with high interindividual variability. Once calibrated, the p-PBPK model was used to simulate fetal exposure to Pb. Internal fetal exposure greatly varies over the pregnancy with two peaks of Pb levels in blood and brain at the end of the 1st and 3rd trimesters. Sensitivity analysis shows that the fetal blood lead levels are affected by the maternal burden of bone Pb via maternal bone remodeling and by fetal bone formation at different pregnancy stages. Coupling the p-PBPK model with an effect model such as an adverse outcome pathway could help to predict the effects on children's neurodevelopment.

A Machine Learning-Based Image Segmentation Method to Quantify In Vitro Osteoclast Culture Endpoints

Quantification of in vitro osteoclast cultures (e.g. cell number) often relies on manual counting methods. These approaches are labour intensive, time consuming and result in substantial inter- and intra-user variability. This study aimed to develop and validate an automated workflow to robustly quantify in vitro osteoclast cultures. Using ilastik, a machine learning-based image analysis software, images of tartrate resistant acid phosphatase-stained mouse osteoclasts cultured on dentine discs were used to train the ilastik-based algorithm. Assessment of algorithm training showed that osteoclast numbers strongly correlated between manual- and automatically quantified values (r = 0.87). Osteoclasts were consistently faithfully segmented by the model when visually compared to the original reflective light images. The ability of this method to detect changes in osteoclast number in response to different treatments was validated using zoledronate, ticagrelor, and co-culture with MCF7 breast cancer cells. Manual and automated counting methods detected a 70% reduction (p < 0.05) in osteoclast number, when cultured with 10 nM zoledronate and a dose-dependent decrease with 1-10 μM ticagrelor (p < 0.05). Co-culture with MCF7 cells increased osteoclast number by ≥ 50% irrespective of quantification method. Overall, an automated image segmentation and analysis workflow, which consistently and sensitively identified in vitro osteoclasts, was developed. Advantages of this workflow are (1) significantly reduction in user variability of endpoint measurements (93%) and analysis time (80%); (2) detection of osteoclasts cultured on different substrates from different species; and (3) easy to use and freely available to use along with tutorial resources.

Contact stress distribution after unilateral condylar fracture with angulation of the fractured part: A finite element model study

After a fracture of the condyle, the head of the condyle is often pulled inwards, which causes the fractured part to angulate medially. This change can cause a disbalance in the masticatory system. The disbalance could lead to contact stress differences within the temporomandibular joints (TMJs) which might induce remodelling within the TMJ to restore the balance. The contact stress in the fractured condyle during open and closing movements is expected to decrease, while the contact stress in the non-fractured condyle will increase. In a clinical situation this is hard to investigate. Therefore, a finite element model (FEM) was used. In the FEM a fractured right condyle with an angulation was induced, which was placed at different degrees, varying from 5° to 50° in steps of 5°. This study shows only minor differences in amount of contact stress between the fractured and the non-fractured condyle. The amount of contact stress in the condyles does not increase with a higher degree of angulation. However, with larger angulations, the contact stress within the fractured condyle is more centralized. Clinically, this more centralized area could be associated with complaints, such as pain. In conclusion, due to the more centralized contact stress in the fractured condyle, one would expect some minor remodelling on the fractured side with more angulation.

Load distribution after unilateral condylar fracture with shortening of the ramus: a finite element model study

OBJECTIVES

After a fracture of the condyle, the fractured ramus is often shortened, which causes premature dental contact on the fractured side and a contralateral open bite. The imbalance could change the load in the temporomandibular joints (TMJs). This change could lead to remodelling of the TMJs to compensate for the imbalance in the masticatory system. The load in the non-fractured condyle is expected to increase, and the load in the fractured condyle to decrease.

MATERIALS AND METHODS

These changes cannot be measured in a clinical situation. Therefore a finite element model (FEM) of the masticatory system was used. In the FEM a fractured right condyle with shortening of the ramus was induced, which varied from 2 to 16 mm.

RESULTS

Results show that, with a larger shortening of the ramus, the load in the fractured condyle decreases and the load in the non-fractured condyle increases. In the fractured condyle during closed mouth a major descent in load, hence a cut-off point, was visible between a shortening of 6 mm and 8 mm.

CONCLUSIONS

In conclusion, the change of load could be associated with remodelling on both condyles due to shortening of the ramus.

CLINICAL RELEVANCE

The cut-off point implies that shortening over 6 mm could present more difficulty for the body to compensate.

Infection-related failure of autologous versus allogenic cranioplasty after decompressive hemicraniectomy - A systematic review and meta-analysis

Introduction

Cranioplasty is required after decompressive craniectomy (DC) to restore brain protection and cosmetic appearance, as well as to optimize rehabilitation potential from underlying disease. Although the procedure is straightforward, complications either caused by bone flap resorption (BFR) or graft infection (GI), contribute to relevant comorbidity and increasing health care cost. Synthetic calvarial implants (allogenic cranioplasty) are not susceptible to resorption and cumulative failure rates (BFR and GI) tend therefore to be lower in comparison with autologous bone. The aim of this review and meta-analysis is to pool existing evidence of infection-related cranioplasty failure in autologous versus allogenic cranioplasty, when bone resorption is removed from the equation.

Materials and methods

A systematic literature search in PubMed, EMBASE, and ISI Web of Science medical databases was performed on three time points (2018, 2020 and 2022). All clinical studies published between January 2010 and December 2022, in which autologous and allogenic cranioplasty was performed after DC, were considered for inclusion. Studies including non-DC cranioplasty and cranioplasty in children were excluded. The cranioplasty failure rate based on GI in both autologous and allogenic groups was noted. Data were extracted by means of standardized tables and all included studies were subjected to a risk of bias (RoB) assessment using the Newcastle-Ottawa assessment tool.

Results

A total of 411 articles were identified and screened. After duplicate removal, 106 full-texts were analyzed. Eventually, 14 studies fulfilled the defined inclusion criteria including one randomized controlled trial, one prospective and 12 retrospective cohort studies. All but one study were rated as of poor quality based on the RoB analysis, mainly due to lacking disclosure why which material (autologous vs. allogenic) was chosen and how GI was defined. The infection-related cranioplasty failure rate was 6.9% (125/1808) for autologous and 8.3% (63/761) for allogenic implants resulting in an OR 0.81, 95% CI 0.58 to 1.13 (Z ​= ​1.24; p ​= ​0.22).

Conclusion

In respect to infection-related cranioplasty failure, autologous cranioplasty after decompressive craniectomy does not underperform compared to synthetic implants. This result must be interpreted in light of limitations of existing studies. Risk of graft infection does not seem a valid argument to prefer one implant material over the other. Offering an economically superior, biocompatible and perfect fitting cranioplasty implant, autologous cranioplasty can still have a role as the first option in patients with low risk of developing osteolysis or for whom BFR might not be of major concern.

Trial registration

This systematic review was registered in the international prospective register of systematic reviews. PROSPERO: CRD42018081720.

Prediction of lumbar disc herniation resorption in symptomatic patients: a prospective, multi-imaging and clinical phenotype study

BACKGROUND CONTEXT

Symptomatic lumbar disc herniations (LDH) are very common. LDH resorption may occur by a "self-healing" process, however this phenomenon remains poorly understood. By most guidelines, if LDH remains symptomatic after 3 months and conservative management fails, surgical intervention may be an option.

PURPOSE

The following prospective study aimed to identify determinants that may predict early versus late LDH resorption.

STUDY DESIGN/SETTING

Prospective study with patients recruited at a single center.

PATIENT SAMPLE

Ninety-three consecutive patients diagnosed with acute symptomatic LDH were included in this study (n=23 early resorption and n=67 late resorption groups) with a mean age of 48.7±11.9 years.

OUTCOMES MEASURE

Baseline assessment of patient demographics (eg, smoking status, height, weight, etc.), herniation characteristics (eg, the initial level of herniation, the direction of herniation, prevalence of multiple herniations, etc.) and MRI phenotypes (eg, Modic changes, end plate abnormalities, disc degeneration, vertebral body dimensions, etc.) were collected for further analysis. Lumbar MRIs were performed approximately every 3 months for 1 year from time of enrollment to assess disc integrity.

METHODS

All patients were managed similarly. LDH resorption was classified as early (<3 months) or late (>3 months). A prediction model of pretreatment factors was constructed.

RESULTS

No significant differences were noted between groups at any time-point (p>.05). Patients in the early resorption group experienced greater percent reduction of disc herniation between MRI-0-MRI-1 (p=.043), reduction of herniation size for total study duration (p=.007), and percent resorption per day compared to the late resorption group (p<.001). Based on multivariate modeling, greater L4 posterior vertebral height (coeff:14.58), greater sacral slope (coeff:0.12), and greater herniated volume (coeff:0.013) at baseline were found to be most predictive of early resorption (p<.05).

CONCLUSIONS

This is the first comprehensive imaging and clinical phenotypic prospective study, to our knowledge, that has identified distinct determinants for early LDH resorption. Early resorption can occur in 24.7% of LDH patients. We developed a prediction model for early resorption which demonstrated great overall performance according to pretreatment measures of herniation size, L4 posterior body height, and sacral slope. A risk profile is proposed which may aid clinical decision-making and managing patient expectations.

Acro-osteolysis: imaging, differential diagnosis, and disposition review

Acro-osteolysis is the osseous destruction of the hand or foot distal phalanges. The categories of the disease include terminal tuft, midshaft, or mixed types. Recognition of acro-osteolysis is straightforward on radiographs, but providing an accurate differential diagnosis and appropriately recommending advanced imaging or invasive tissue diagnosis can be more elusive. A radiologist's ability to provide advanced assessment can greatly aid clinicians in expedient diagnosis and management of the array of diseases presenting with acro-osteolysis.

The "Mellanby effect" in alcoholised e-scooter drivers

PURPOSE

Several studies tried to discuss and clarify the so-called Mellanby effect: Similar blood alcohol concentrations (BACs) supposedly lead to more signs of impairment in the phase of alcohol resorption than elimination. To assess this effect for alcoholised e-scooter driving, results of a real-driving fitness study were subanalysed.

METHODS

Sixteen subjects (9 females; 7 males) who completed runs at comparable BACs in the phases of alcohol resorption and elimination were chosen to assess a possible "Mellanby effect". The data of the subjects was taken from a prior e-scooter study by Zube et al., which included 63 subjects in total.

RESULTS

In the phase of alcohol resorption, the relative driving performance was approx. 92% of the phase of elimination (p value 0.21). Statistically significant more demerits were allocated to the obstacle "narrowing track" in the phase of resorption than elimination. Subjects also needed significantly more time to pass the obstacles "narrowing track", "driving in circles counterclockwise" and "thresholds" in the phase of resorption than elimination.

DISCUSSION

The most relevant obstacle to discriminate between the two different states of alcoholisation was the narrowing track. Insofar, measurements of the standard deviation of the lateral position (SDLP) might also be a sensitive component for the detection of central nervous driving impairment during shorter trips with an e-scooter. Additionally, driving slower during the phase of alcohol resorption seems to be the attempt to compensate alcohol-related deficits.

CONCLUSION

The results of the study suggest a slight Mellanby effect in e-scooter drivers.

The effects of seeding density and osteoclastic supplement concentration on osteoclastic differentiation and resorption

The bone resorbing osteoclasts are a complex type of cell essential for in vivo bone remodeling. There is no consensus on medium composition and seeding density for in vitro osteoclastogenesis, despite the importance thereof on osteoclastic differentiation and activity. The aim of this study was to investigate the relative effect of monocyte or peripheral blood mononuclear cell (PBMC) seeding density, osteoclastic supplement concentration and priming on the in vitro generation of functional osteoclasts, and to explore and evaluate the usefulness of commonly used markers for osteoclast cultures. Morphology and osteoclast formation were analyzed with fluorescence imaging for tartrate resistant acid phosphatase (TRAP) and integrin β3 (Iβ3). TRAP release was analyzed from supernatant samples, and resorption was analyzed from culture on Corning® Osteo Assay plates. In this study, we have shown that common non-standardized culturing conditions of monocyte or PBMCs had a significant effect on the in vitro generation of functional osteoclasts. We showed how increased osteoclastic supplement concentrations supported osteoclastic differentiation and resorption but not TRAP release, while priming resulted in increased TRAP release as well. Increased monocyte seeding densities resulted in more and large TRAP positive bi-nuclear cells, but not directly in more multinucleated osteoclasts, resorption or TRAP release. Increasing PBMC seeding densities resulted in more and larger osteoclasts and more resorption, although resorption was disproportionally low compared to the monocyte seeding density experiment. Exploration of commonly used markers for osteoclast cultures demonstrated that Iβ3 staining was an excellent and specific osteoclast marker in addition to TRAP staining, while supernatant TRAP measurements could not accurately predict osteoclastic resorptive activity. With improved understanding of the effect of seeding density and osteoclastic supplement concentration on osteoclasts, experiments yielding higher numbers of functional osteoclasts can ultimately improve our knowledge of osteoclasts, osteoclastogenesis, bone remodeling and bone diseases.

Tuning the resorption-formation balance in an in vitro 3D osteoblast-osteoclast co-culture model of bone

The aim of the present study was to further improve an in vitro 3D osteoblast (OB) - osteoclast (OC) co-culture model of bone by tuning it towards states of formation, resorption, and equilibrium for their future applications in fundamental research, drug development and personalized medicine. This was achieved by varying culture medium composition and monocyte seeding density, the two external parameters that affect cell behavior the most. Monocytes were seeded at two seeding densities onto 3D silk-fibroin constructs pre-mineralized by MSC-derived OBs and were co-cultured in one of three different media (OC stimulating, Neutral and OB stimulating medium) for three weeks. Histology showed mineralized matrix after co-culture and OC markers in the OC medium group. Scanning Electron Microscopy showed large OC-like cells in the OC medium group. Micro-computed tomography showed increased formation in the OB medium group, equilibrium in the Neutral medium group and resorption in the OC medium group. Culture supernatant samples showed high early tartrate resistant acid phosphatase (TRAP) release in the OC medium group, a later and lower release in the Neutral medium group, and almost no release in the OB medium group. Increased monocyte seeding density showed a less-than-proportional increase in TRAP release and resorption in OC medium, while it proportionally increased TRAP release in Neutral medium without affecting net resorption. The 3D OB-OC co-culture model was effectively used to show an excess of mineral deposition using OB medium, resorption using OC medium, or an equilibrium using Neutral medium. All three media applied to the model may have their own distinct applications in fundamental research, drug development, and personalized medicine.

Surgical placement of third molars to replace other teeth: “spare wheels”]

Introduction

The prognostic improvement for dental auto-transplants is the result of a better understanding in the physiopathology of the periodontium and also of the refining of the technical operative procedure. This fact allows the use of third molars as donor site for the replacement of absent, or first or second badly decayed molars.

Discussion

This possible therapy is a supplement argument for the conservation of third molars and their extraction must be indicated only when the anatomic situation presents a pathological risk.

Results

If, in adults, it is possible to compare the advantages and disadvantages with the classical implant or prosthetic techniques, it should however be considered as first choice therapy for adolescents and young adults. Indeed, in these cases, the lower risk of root ankylosis avoids passive intrusion and the osteogenic effect of the desmodontium allows normal alveolar bone formation.

The origins and formation of bone-resorbing osteoclasts

Osteoclasts (OCLs) are hematopoietic cells whose physiological function is to degrade bone. OCLs are key players in the processes that determine and maintain the mass, shape, and physical properties of bone. OCLs adhere to bone tightly and degrade its matrix by secreting protons and proteases onto the underlying surface. The combination of low pH and proteases degrades the mineral and protein components of the matrix and forms a resorption pit; the degraded material is internalized by the cell and then secreted into the circulation. Insufficient or excessive activity of OCLs can lead to significant changes in bone and either cause or exacerbate symptoms of diseases, as in osteoporosis, osteopetrosis, and cancer-induced bone lysis. OCLs are derived from monocyte-macrophage precursor cells whose origins are in two distinct embryonic cell lineages - erythromyeloid progenitor cells of the yolk sac, and hematopoietic stem cells. OCLs are formed in a multi-stage process that is induced by the cytokines M-CSF and RANKL, during which the cells differentiate, fuse to form multi-nucleated cells, and then differentiate further to become mature, bone-resorbing OCLs. Recent studies indicate that OCLs can undergo fission in vivo to generate smaller cells, called "osteomorphs", that can be "re-cycled" by fusing with other cells to form new OCLs. In this review we describe OCLs and discuss their cellular origins and the cellular and molecular events that drive osteoclastogenesis.

Bioceramics utilization for the repair of internal resorption of the root: A case report

BACKGROUND

The objective of this work is displaying a successful treatment for an internal resorption case under operating microscope using bioceramic material.

CASE SUMMARY

Periapical radiograph showed radiolucent lesion representing large internal resorption of the root. The respective defect was obturated using endoscquence bioceramic material follow up at the month 18 after treatment revealed no abnormal finings clinically and radiographically.

CONCLUSION

New generations bioceramics have many advantages that internal root resorption cases can benefit from. The use of operating microscope helps to apply obturating materials with precision. However, long term study on a large sample is required in future studies.

Proximal humeral bone loss in stemless shoulder arthroplasty: potential factors influencing bone loss and a new classification system

INTRODUCTION

Proximal humeral bone loss in total shoulder arthroplasty (TSA) is more frequent than in hemiarthroplasty. Factors such as age, gender, inclination angle, and radiolucent lines may also contribute. Additionally, current bone loss grading systems are often not sensitive enough to detect slight bone changes, especially at the medial calcar where bone loss is commonly observed. This study uses a new, more detailed bone loss grading system to evaluate factors that could influence bone loss at the proximal humerus.

MATERIALS AND METHODS

In this single-center prospective study, patients underwent hemiarthroplasty or TSA with an anatomic stemless prosthesis. Bone loss was measured at the proximal humerus using the new grading system. The effect of treatment type, age, gender, radiolucent lines, and inclination angle on bone loss was evaluated. The Constant-Murley score of patients was assessed and complications recorded.

RESULTS

Ninety-one shoulders were available for the final follow-up examination at a median of 85.0 months (range 82.6-121.1 months). Bone loss was found at the proximal humerus in approximately one-third of shoulders, and significantly more shoulders had bone loss in TSA than in hemiarthroplasty (P = 0.03). However, this difference was no longer significant after stratifying by gender and age (P > 0.05). Bone loss significantly correlated with gender (P = 0.03) but not with treatment type, radiolucent lines, and the postoperative inclination angle (P > 0.05). Most Constant-Murley score components did not differ significantly between shoulders with and without bone loss (P > 0.05). Lastly, six complications and four revisions were reported.

CONCLUSIONS

Results showed gender had the greatest influence on bone loss after stemless shoulder arthroplasty. Furthermore, both patients with or without bone loss can expect similar clinical outcomes with the stemless prosthesis used in this study. Lastly, the new grading system is simple and straightforward to use.

Humeral stem with low filling ratio reduces stress shielding in primary reverse shoulder arthroplasty

PURPOSE

Some patients show severe humeral bone stress shielding even one year after press-fit humeral stem, which can be a risk factor for implant durability. This study compared humeral stress shielding and clinical outcomes between high and low filling ratio (HFR and LFR) stems in primary reverse shoulder arthroplasty (RSA).

METHODS

From 2015 to 2020, 104 patients who underwent RSA with a non-cemented standard-length humeral stem were examined. The humeral stems included large press-fit stems (HFR group, 53 patients) or small non-press-fit stems with autogenous cancellous bone grafting (LFR group, 51 patients). The radiologic and clinical outcomes were compared between the groups one year post-operatively.

RESULTS

One patient in the LFR group with early infectious dislocation was excluded from the 1-one year evaluation. No stress shielding was observed in 27/50 (54.0%) and 5/53 (9.4%) of patients in the LFR and HFR groups, while 3/50 (6%) and 19/53 (35.8%) patients showed high-stress shielding, respectively. However, the stem alignment change, subsidence, complications and evidence of loosening did not differ between the groups. The final range-of-motion and functional scores were significantly poorer in the LFR group than those in the HFR group, although the difference was minimal.

CONCLUSION

Even at one year follow-up, patients receiving LFR stems with autogenous bone grafting had significantly less humeral stress shielding compared to patients with HFR stem with press-fit in primary RSA, without compromising stem stability.

Novel insights into the coupling of osteoclasts and resorption to bone formation

Bone remodeling consists of resorption by osteoclasts (OCs) and formation by osteoblasts (OBs). Precise coordination of these activities is required for the resorbed bone to be replaced with an equal amount of new bone in order to maintain skeletal mass throughout the lifespan. This coordination of remodeling processes is referred to as the "coupling" of resorption to bone formation. In this review, we discuss the essential role for OCs in coupling resorption to bone formation, mechanisms for this coupling, and how coupling becomes less efficient or disrupted in conditions of bone loss. Lastly, we provide perspectives on targeting coupling to treat human bone disease.

Resorbable Collagen Barrier Impeding the Extrusion of Obturating Material in Primary Molars Undergoing Resorption - A Randomized Clinical Trial

OBJECTIVE

To evaluate the effectiveness of placing a resorbable collagen barrier in impeding the extrusion of obturation material in primary molars undergoing resorption.

STUDY DESIGN

All the 94 canals in 47 mandibular molars were allocated to 2 groups- Group 'A'- 47 canals with collagen barrier (Test group) and Group 'B'- 47 canals without collagen barrier (Control group) based on randomization protocol. Pulpectomy was performed and obturation of both test and control canals were radiographically assessed. Pearson's chi - square test was applied to analyze the results. The significance level was predetermined at p < 0.05.

RESULTS

Among the test group, 93.6% of the canals showed no extrusion while, 6.4% showed visible extrusion of the material outside the apex. In the control group, 83% showed no extrusion whereas 17% of the canals showed visible extrusion outside the apex. But no significant difference was noted (p>0.05).

CONCLUSION

The placement of resorbable collagen barrier in the apical third of the canal prevented the extrusion of obturating material beyond the apex in resorbing primary molars.

Mathematical modeling of the role of bone turnover in pH regulation in bone interstitial fluid

BACKGROUND AND AIMS

Bone turnover is strongly affected by pH of surrounding fluid, and in turn plays a role in maintaining systemic pH, however the quantitative contribution of bone processes to pH regulation is not known. Our goal was to develop a mathematical model describing pH regulation in the interstitial fluid and to examine the contribution of hydroxyapatite dissolution and precipitation to pH regulation.

MATERIALS AND METHODS

We modeled twelve reversible equilibrium reactions of sixteen calcium, phosphate, hydrogen and carbonate species in the interstitial fluid and examined the buffering capacity and range. The effect of hydroxyapatite dissolution and precipitation was modeled by assuming that the calcium, phosphate and hydroxide contained in the bone volume adjacent to the interstitial fluid is instantaneously added to or removed from the interstitial fluid.

RESULTS

The carbonate buffer was found to dominate electrochemical buffering system of the bone interstitial fluid. Nevertheless, the phosphate added during dissolution of bone hydroxyapatite significantly improved the interstitial fluid buffering capacity. In contrast, hydroxyapatite precipitation had limited effect on the interstitial fluid pH regulation.

CONCLUSION

This study provides mechanistic insights into the physicochemical processes underlying the known role of bone turnover processes in regulation of body pH homeostasis.

Young adult with Gorham's disease presenting in an emergency department: a case report

Introduction

Gorham’s disease is a very rare musculoskeletal disorder characterized by progressive resorption of one or more skeletal bones. Most of the 200 cases reported earlier are diagnosed before the age of 40 years. Due to rarity, the diagnosis of Gorham’s disease in the Emergency Department may be very difficult.

Case presentation

We report a case of Gorham’s disease. A 23-year old Caucasian man presented to the Emergency Department with a significant loss of power and sensation of the lower limbs and lower torso. Clinical examination, computed tomography, and magnetic resonance imaging revealed resorption of the ribs and vertebrae, severe kyphosis, and spinal stenosis in the thoracic area. The patient underwent several surgical procedures, including spondylodesis and decompression, and made a good initial recovery. Biopsy confirmed the diagnosis of Gorham’s disease.

Conclusion

We present a young man with Gorham’s disease visiting the Emergency Department. After the proper diagnosis and treatment, our patient had good outcome, although the etiology of this rare disease is uncertain.

Bone Flap Resorption in Pediatric Patients Following Autologous Cranioplasty

Following a decompressive craniectomy, the autologous bone flap is generally considered the reconstructive material of choice in pediatric patients. Replacement of the original bone flap takes advantage of its natural biocompatibility and the associated low risk of rejection, as well as the potential to reintegrate with the adjacent bone and subsequently grow with the patient. However, despite these advantages and unlike adult patients, the replaced calvarial bone is more likely to undergo delayed bone resorption in pediatric patients, ultimately requiring revision surgery. In this review, we describe the materials that are currently available for pediatric cranioplasty, the advantages and disadvantages of autologous calvarial replacement, the incidence and classification of bone resorption, and the clinical risk factors for bone flap resorption that have been identified to date.

Radiographic evaluation of reactive osteitis in traumatic injury of sacroiliac joints

OBJECTIVES

After traumatic Sacroiliac (SI) joint injury, follow up radiographic imaging can demonstrate subchondral bone resorption resembling inflammatory sacroiliitis. No studies have described the incidence of marginal SI post-traumatic osteitis, the probable temporal relationship to the initial traumatic injury, or the possible effect of unilateral hardware fixation on the contralateral SI joint.

METHODS

A Level 1 trauma center imaging database was queried to identify patients with pelvic bony trauma between 2005 and 2017 with CT baseline preserved SI cortication and unilateral/bilateral traumatic SI diastasis. Serial radiographs were retrospectively evaluated by 2 musculoskeletal-trained radiologists at initial, 6 weeks, 3 months and 6 months following trauma, with documentation of diastasis, subchondral resorption, and operative fixation.

RESULTS

206 SI joints in 106 total patients met inclusion criteria. There was a statistically significant association between injury and presence of resorption at 6 weeks post-trauma for the right SI joint only. There was no other statistically significant relationship between injury and presence of resorption at any other post-trauma evaluation. There was no statistical relationship between resorption and surgical fixation. There was a statistically significant increased incidence of resorption in the post-traumatic population when compared to an atraumatic population undergoing CT pelvis study for non-SI related indications as well as compared to the incidence of inflammatory sacroiliitis in a general population.

CONCLUSIONS

This study confirms an incidence of sub-acute subchondral bone resorption following traumatic joint injury above that expected for a general, non-traumatic population. Accurate interpretation of this traumatic finding minimizes inappropriate consultation and intervention for inflammatory sacroiliitis.

Idiopathic coronal resorption in impacted permanent teeth and its relationship with age: radiologic study

Purpose

The purpose of this study was to evaluate the relationship between idiopathic coronal resorption and age in adult patients.

Materials and methods

3405 digital panoramic radiographs present in the archive of the radiology department belonging to 1584 males and 1821 females aged 25 and over were assessed by two oral and maxillofacial radiologists. The patients' age, gender, number of impacted teeth, number and position of teeth with idiopathic coronal resorption and the extent of coronal resorption were recorded on standard forms.

Results

A thousand and nine impacted teeth were observed in 622 patients (304 males and 318 females) with a mean age of 36,92 (±10,85). Idiopathic coronal resorption was present in 26 of the 622 patients with a frequency of 4.2%. One patient had two teeth with idiopathic coronal resorption; resulting in as 27 teeth and a frequency of 2.7% according to tooth number. There were 13 (50%) females and 13 (50%) males having idiopathic coronal resorption. There was no significant difference between genders. The presence of idiopathic coronal resorption increased with advanced age (v: 0,193, p<0.05). There was no statistically significant difference between the extent of the coronal resorption and age.

Conclusion

The presence of idiopathic coronal resorption increases with advancing age. Idiopathic coronal resorption is detected incidentally during radiographic examination. Thus, dentists should consider this situation and should perform periodically radiographic examination of impacted teeth.

Unraveling the mystery of Gaucher bone density pathophysiology

Gaucher disease (GD) is caused by pathogenic mutations in GBA1, the gene that encodes the lysosomal enzyme β-glucocerebrosidase. Despite the existence of a variety of specific treatments for GD, they cannot completely reverse bone complications. Many studies have evidenced the impairment in bone tissue of GD, and molecular mechanisms of bone density alterations in GD are being studied during the last years and different reports emphasized its efforts trying to unravel why and how bone tissue is affected. The cause of skeletal density affection in GD is a matter of debates between research groups. and there are two opposing hypotheses trying to explain reduced bone mineral density in GD: increased bone resorption versus impaired bone formation. In this review, we discuss the diverse mechanisms of bone alterations implicated in GD revealed until the present, along with a presentation of normal bone physiology and its regulation. With this information in mind, we discuss effectiveness of specific therapies, introduce possible adjunctive therapies and present a novel model for GD-associated bone density pathogenesis. Under the exposed evidence, we may conclude that both sides of the balance of remodeling process are altered. In GD the observed osteopenia/osteoporosis may be the result of contribution of both reduced bone formation and increased bone resorption.

The human sialic acid-binding immunoglobulin-like lectin Siglec-9 and its murine homolog Siglec-E control osteoclast activity and bone resorption

Regulation of osteoclast differentiation and function is a central element in bone homeostasis. While the role of soluble factors, such as cytokines, hormones and growth factors, in controlling osteoclast differentiation has been intensively characterized, the function of surface receptors is less well understood. Sialic acid-binding immunoglobulin-like lectin (Siglec)-9 and its murine homolog Siglec-E are sialic acid-recognizing inhibitory receptors from the CD33-related Siglec-family and mainly expressed on myeloid cells. We found Siglec-9 and Siglec-E to be expressed at all stages of human and murine osteoclastogenesis, respectively. Siglec-E knockout mice displayed lower bone mass despite unchanged osteoclast numbers and an increased bone formation rate. Ex vivo osteoclast assays using Siglec-E knockout cells or a blocking antibody against human Siglec-9 confirmed the suppressive effect of Siglec-9/Siglec-E on osteoclast function. Although osteoclast numbers were unchanged or even slightly decreased, the blockade/absence of Siglec-9/Siglec-E resulted in an augmented resorption activity of mature osteoclasts. This increased resorption activity was associated with enlarged actin rings. Together, our results suggest Siglec-9/Siglec-E to inhibit osteoclast activation independently from osteoclast differentiation and thereby propose a new mechanism for the control of local bone resorption.

Low doses of uranium and osteoclastic bone resorption: key reciprocal effects evidenced using new in vitro biomimetic models of bone matrix

Uranium is widely spread in the environment due to its natural and anthropogenic occurrences, hence the importance of understanding its impact on human health. The skeleton is the main site of long-term accumulation of this actinide. However, interactions of this metal with biological processes involving the mineralized extracellular matrix and bone cells are still poorly understood. To get a better insight into these interactions, we developed new biomimetic bone matrices containing low doses of natural uranium (up to 0.85 µg of uranium per cm²). These models were characterized by spectroscopic and microscopic approaches before being used as a support for the culture and differentiation of pre-osteoclastic cells. In doing so, we demonstrate that uranium can exert opposite effects on osteoclast resorption depending on its concentration in the bone microenvironment. Our results also provide evidence for the first time that resorption contributes to the remobilization of bone matrix-bound uranium. In agreement with this, we identified, by HRTEM, uranium phosphate internalized in vesicles of resorbing osteoclasts. Thanks to the biomimetic matrices we developed, this study highlights the complex mutual effects between osteoclasts and uranium. This demonstrates the relevance of these 3D models to further study the cellular mechanisms at play in response to uranium storage in bone tissue, and thus better understand the impact of environmental exposure to uranium on human bone health.

Dopamine D1 receptor stimulates cathepsin K-dependent degradation and resorption of collagen I in lung fibroblasts

Matrix resorption is essential to the clearance of the extracellular matrix (ECM) after normal wound healing. A disruption in these processes constitutes a main component of fibrotic diseases, characterized by excess deposition and diminished clearance of fibrillar ECM proteins, such as collagen type I. The mechanisms and stimuli regulating ECM resorption in the lung remain poorly understood. Recently, agonism of dopamine receptor D1 (DRD1), which is predominantly expressed on fibroblasts in the lung, has been shown to accelerate tissue repair and clearance of ECM following bleomycin injury in mice. Therefore, we investigated whether DRD1 receptor signaling promotes the degradation of collagen type I by lung fibroblasts. For cultured fibroblasts, we found that DRD1 agonism enhances extracellular cleavage, internalization and lysosomal degradation of collagen I mediated by cathepsin K, which results in reduced stiffness of cell-derived matrices, as measured by atomic force microscopy. In vivo agonism of DRD1 similarly enhanced fibrillar collagen degradation by fibroblasts, as assessed by tissue labeling with a collagen-hybridizing peptide. Together, these results implicate DRD1 agonism in fibroblast-mediated collagen clearance, suggesting an important role for this mechanism in fibrosis resolution.This article has an associated First Person interview with the first author of the paper.

[Sagittal Balance Parameters Correlate with Resorption of the Lumbar Disc Extrusion: Results of a Retrospective Study]

Objective

A retrospective study was designed to explore the relationship between the satittal spinopelvic alignment in patients with lumbar disc extrusion and spontaneous resorption.

Methods

From May 2010 to March 2019, referring to NASS evidence-based clinical guidelines, patients with lumbar disc extrusion were enrolled in this retrospective study, according to the degree of herniation size during the follow-up, the patients were divided into two groups: resorption (group R: the herniated disc completely disappeared or the herniation size was grade 1 according to Michgan State University (MSU) classification) and nonresorption (group N: the herniated disc remain unchanged or the herniation size overpass grade 1), spinopelvic parameters (including the pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL)) were determined on standing profile radiographs of the lumbar spine and pelvis, and mean values were compared using the multi-factor analysis of variance.

Results

This study included 67 patients with lumbar disc extrusion. There were 37 in group R (the average age was 42.6 years), 21 males and 16 females, 13 cases at L _4-5 level and 24 cases at L ₅-S ₁ level, follow-up 22 months, and 30 in group N (the average age was 40.8 years), 19 males and 11 females, 12 cases at L _4-5 level and 18 cases at L ₅-S ₁ level, follow-up 21 months, at the follow up time, there symptoms were all satisfactorily relieved. There were no signifcant differences in age, gender, smoking history, chronic medical history, prominent segmnet, MSU classification, follow up time and other baseline conditions between two groups ( P>0.05). At the follow-up, in group R, all 30 cases of sagittal displaced disc disappeared, the herniated disc changed from the initial MSU classification of grade 2 in 19 cases and grade 3 in 18 cases to the post-absorption residual disc, which were limited to grade 1; in group N, 20 cases of sagittal displaced disc reduced to 14 cases, the herniated disc changed from the initial MSU classification of grade 2 in 21 cases and grade 3 in 9 cases to grade 2 in 27 cases and grade 3 in 3 cases. There was no significant difference in spinopelvic parameters between the two groups before the treatment ( P>0.05). At the follow-up, there was no significant difference in PI between the two groups ( P>0.05); the SS and LL in group R were bigger than those in group N, the PT in group R was smaller than that in group N, and the difference was statistically significant ( P<0.05). Compared within the same group, before treatment and follow-up, there were no significant differences in PI, SS and PT in group R, but a bigger LL ( P<0.05); no significant differences in all the parameters in group N were found.

Conclusion

Resorption may result in pinopelvic parameter changes, which suggest that the lumbar spine is better at cushioning against load, reducing the disc pressure, and leading to resorption of the herniated disc.

Seasonal variation in the onset of acute calcific tendinitis of rotator cuff

Background

Calcific tendinitis of the rotator cuff is a disorder that causes acute onset of shoulder pain when spontaneous resorption of the calcification occurs. However, factors that trigger calcium resorption have not been clarified. The present study aimed to investigate the association between the onset of calcium resorption in calcific tendinitis and the season of onset.

Methods

We retrospectively reviewed 195 patients (female, 116; male, 79; mean age, 62.6 ± 14.2 years; median age, 62 [52, 73] years) diagnosed with the postcalcification stage of calcific tendinitis, which was defined as acute calcific tendinitis in this study, between 2006 and 2018. The onset date of acute calcific tendinitis for each patient was collected from clinical notes. We evaluated the incidence of acute calcific tendinitis in each season and month. Furthermore, we investigated the correlation between the incidence of acute calcific tendinitis and the mean monthly temperature or humidity levels for each year.

Results

The most common season of acute calcific tendinitis onset was summer (35.4%), followed by spring (24.6%), autumn (24.1%), and winter (15.9%) (P = 0.002). Monthly analyses showed the highest peak of onset was in July (15.4%) and the lowest peak was in February (3.1%) (P = 0.022). The incidence of acute calcific tendinitis had a weak association with mean monthly temperature (R² = 0.066; P = 0.001) but was not associated with mean monthly humidity levels (R² = 0.018; P = 0.099).

Conclusions

This study provides new information on seasonal variation of acute calcific tendinitis onset. The results of this study indicated that the onset of calcium resorption occurs most frequently in the summer in Japan; however, the reasons for seasonal variation remain unclear, and further studies will be needed.

Level of evidence

Level III.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-020-03773-6.

Long-Term Arterial Remodeling After Bioresorbable Scaffold Implantation 4-Year Follow-up of Quantitative Coronary Angiography, Histology and Optical Coherence Tomography

PURPOSE

Our previous studies have confirmed the safety and efficacy of the novel fully bioresorbable PLLA scaffold (PowerScaffold®) at 12 months implantation. In the present study, the scaffold absorption and coronary vessel remodeling at 4 years were evaluated.

METHODS

After PowerScaffold® were implanted into 13 coronary arteries of 6 miniature pigs, quantitative coronary angiography (QCA) was performed at 15 days and 4 years follow-up to measure the mean lumen diameter (MLD), late lumen loss (LLL), and % stenosis of the coronary arteries. Optical coherence tomography (OCT) was performed to obtain the strut footprints at 4 years before euthanization for histological analysis. In addition, 2 PowerScaffold® were implanted into 2 miniature pigs for 2 years as supplementary data. All stented arteries were dissected and stained with HE, Masson, EVG, and Alcian blue to observe struts, cells, fibrinoid, elastin, and proteoglycans, respectively.

RESULTS

There were no significant differences in MLD, LLL and % stenosis in stented coronary arteries between 15 days and 4 years by QCA. At 4 years, most strut sites were indiscernible and replaced by extracellular matrix and connective tissue by histology. Both strut/vessel wall interaction and strut coverage were shown 100% by OCT.

CONCLUSION

At 4 years, the scaffold struts were completely embedded into vessel wall and mostly replaced by regenerated tissue. There was no sign of in-stent stenosis in all stented arteries.

Non-surgical treatment with XSHHD for ruptured lumbar disc herniation: a 3-year prospective observational study

Background

Lumbar disc herniation (LDH) is mainly caused by annular fiber disruption with a discrete leakage of nucleus pulposus pressing on a nerve, resulting in back pain and radiating pain. Most patients with LDH can be treated conservatively, but there are many different conservative treatments. Furthermore, most previous studies did not evaluate the long-term efficacy of these treatments and the prognosis. Therefore, an effective and safe therapeutic strategy is lacking for patients with LDH. In this study, we evaluated Xiao Sui Hua He decoction (XSHHD) in the treatment of LDH.

Methods

This was a rigorous prospective observational 3-year follow-up study. We recruited 69 participants with ruptured lumbar disc herniation (RLDH) between February 2014 and February 2016. Patients took XSHHD orally twice a day for 6 months. The primary outcome measurements were visual analogue scale (VAS) pain score, Oswestry disability index (ODI) and straight leg raising test (SLRT). The secondary outcome measurements was nucleus pulposus protrusion volume on magnetic resonance imaging (MRI). Clinical outcomes were measured at baseline (Visit 1), and at 3, 6, 12, and 36 months (Visit 2, 3, 4, and 5, respectively)..

Results

Sixty-three patients were followed-up for 3 years after treatment. SLRT and ODI after non-surgical treatment improved significantly compared with baseline (P < .001). There were no statistically significant differences at 6 months vs 36 months for SLRT and ODI. VAS scores (leg, back) after 3 years of treatment were statistically significantly different compared with baseline (P < .001; Z = − 6.93, − 6.637). The baseline protrusion volume was 2018.61 ± 601.16 mm³, and the volume decreased significantly to 996.51 ± 387.42 mm3 at 36 months (t = 12.863; P < .001). The volume of protrusion resorption rate (VPRR) at 36 months was 47.24 ± 23.99%, with significant resorption in 23 cases, partial resorption in 23 cases, no resorption in 15 cases, and increased volume in 2 cases.

Conclusions

This study showed that non-surgical treatment with XSHHD was effective, and the study clarified the natural outcomes in LDH.

Resorption of upwardly displaced lumbar disk herniation after nonsurgical treatment: A case report

BACKGROUND

The spontaneous resorption of lumbar disk herniations (LDHs) has been widely reported. However, the majority of these reports analyze the resorption of LDHs that were displaced backwards or downwards. There have been few reports on the spontaneous resorption of upwardly displaced L4/5 LDH that has caused femoral nerve symptoms.

CASE SUMMARY

A 55-year-old woman presented to our hospital with acute pain in her left leg. She had been suffering from recurrent lower back pain for approximately 1 year and began to feel pain accompanied with numbness at the anterior aspect of her left leg 7 d previously. On examination, a typical L4 nerve stimulation was noted. An upwardly displaced LDH at the L4/5 level was revealed by magnetic resonance imaging. The patient attained complete relief of her symptoms after 10 wk of nonsurgical treatment and the upwardly displaced herniation almost entirely disappeared. There was no recurrence during a follow-up of 2 years.

CONCLUSION

Clinicians should be aware that the nerves disturbed by LDHs vary according to the direction of the herniations and the probable resorption of upwardly displaced LDHs should be considered before making a decision on surgery.

Electroacupuncture Might Promote the Spontaneous Resorption of Lumbar Disc Herniation: A Case Report

BACKGROUND

Although acupuncture is effective in the treatment of lumbar disc herniation (LDH), based on comprehensive literature review, reports of the resorption of large herniated discs in LDH patients treated merely by acupuncture are very rare.

CASE REPORT

A 49-year-old patient presented with distending pain in the left lower limb and numbness on the dorsum of the left foot. Physical examination revealed positive signs associated with mechanical compression by herniated lumbar discs. Magnetic resonance imaging (MRI) at symptom onset confirmed the diagnosis of LDH at L4-L5 and L5-S1. Electroacupuncture was administered on local acupoints combined with distal acupoints. His clinical symptoms gradually improved with time throughout acupuncture treatment, verified by increased Japanese Orthopaedic Association scores. The patient was discharged after a total of 20 acupuncture sessions within 1 month. Follow-up indicated that his symptoms had disappeared completely at 1.5 months after discharge and had not recurred since then. At the 10-month follow-up, MRI re-examination confirmed that the herniated discs had been resorbed significantly.

CONCLUSION

Electroacupuncture could significantly improve clinical symptoms and might promote the spontaneous resorption of herniated discs in LDH patients. Thus, for LDH patients suitable for conservative treatment, electroacupuncture could be a favourable option recommended to patients.

One versus two anterior miniscrews for correcting upper incisor overbite and angulation: a retrospective comparative study

Background

Miniscrews are effective devices for performing upper incisor intrusion. Different mechanics can be applied depending on the treatment objectives. This study aimed to evaluate the efficacy of one or two anterior miniscrews for upper incisor correction in cases of overbite and angulation in adult patients.

Methods

Forty-four adults with deep overbite were divided into two groups: group 1 was treated with one miniscrew between upper central incisors and group 2 with two miniscrews between upper lateral incisors and canines. Incisor intrusion and length were measured from lateral cephalograms before treatment, after treatment and at least 12 months into retention (T0, T1 and T2). Forces were applied (90 g) from the miniscrews to the archwire using elastomeric chains. ANOVA analysis was used to determine whether differences between evaluation times were statistically significant.

Results

Mean root resorption was 2.15 ± 0.85 mm, which ceased after active treatment. Overbite mean correction was − 3.23 ± 1.73 mm with no statistically significant relapse. Overbite correction and incisor intrusion were significantly greater in group 2 (− 3.80 ± 1.43 versus − 2.75 ± 1.63 for OB and 8.19 ± 3.66 versus 5.69 ± 2.66 for intrusion). Resorption and overbite correction were positively related. No counterclockwise rotation of the mandibular plane was observed.

Conclusions

Overbite correction can be performed by means of upper incisor intrusion without rotation of the mandibular plane. Correction of upper incisor intrusion and overbite is greater in patients treated with two miniscrews. The increase in upper incisor buccal angulation is greater with one miniscrew. Root resorption is positively related to the extent of intrusion. Stability is satisfactory regardless of whether one or two miniscrews are used.

Irradiated homologous costal cartilage grafts for single-stage open airway reconstruction in severe subglottic stenosis for children under the age of one

We present two cases of premature infants with Cotton-Myer grade 3 subglottic stenosis where endoscopic balloon dilation failed. In an attempt to avoid tracheostomy, both patients underwent open single stage anterior graft larnygotracheoplasty (LTP) with irradiated homologous rib and temporalis fascia grafts. After postoperative reconstruction, the airway was resized to grade 1 in one child, and to grade 2 in the other. One child remained free of stridor post-operatively and avoided the need of a tracheostomy tube. The other child ultimately required a tracheostomy, though she is now in the process of being decannulated. Homologous costal cartilage grafts in open anterior airway LTP may be a reasonable alternative to tracheostomy in young patients with advanced SGS.

Understanding stoichiometric mechanisms of nutrient retention in wetland macrophytes: stoichiometric homeostasis along a nutrient gradient in a subtropical wetland

Nutrient homeostasis relates ambient stoichiometric conditions in an environment to the stoichiometry of living entities of that ecosystem. Plant nutrient sequestration in wetland ecosystems is a key process for downstream water quality. However, few studies have examined stoichiometric homeostasis of aquatic vegetation despite the importance of stoichiometry to plant nutrient uptake efficiency. This study investigated stoichiometric homeostasis of dominant emergent and submerged aquatic vegetation (EAV and SAV, respectively) within two treatment flow-ways of Everglades Stormwater Treatment Area 2 (STA-2). These flow-ways encompass a large gradient in plant nutrient availability. This study hypothesizes that wetland vegetation is homeostatic relative to ambient nutrients and consequently nutrient resorption does not vary along the nutrient gradient. We developed a framework to investigate how vegetation uptake and resorption of nutrients contribute separately to homeostasis. Overall, we determined that the wetland vegetation in this study was non-homeostatic with respect to differential uptake of nitrogen (N) versus phosphorus (P). In EAV, P resorption was relatively high and N resorption was moderate, and resorption efficiency did not vary significantly along the gradient. In separating the proportional contribution of resorption and uptake to the degree of homeostasis, resorption did not affect overall homeostatic status in EAV.

Teeth resorption at cement - enamel junction (CEJ) - Microscopy analysis

The cement - enamel junction (CEJ) gains a growing interest in clinical dentistry, due to an increasing number of idiopathic tooth resorption leading to the inevitable loss of permanent dentition. Therefore, in this research study, we investigated healthy and under resorption teeth to verify junctions' morphology in relation to the resorption process, its initiation, and propagation. Using light and scanning electron microscopy we examined the three types of CEJ: 1) coronal cementum, 2) abutment) and 3) the gap between cementum and enamel. With energy-dispersive X-ray spectroscopy (EDX) we analyzed the Ca and P concentration along the CEJ border. The study indicated the strict correlation between the gap junction and tooth resorption, due to the dentine exposure to the oral environment.

[A 5 year follow-up study on non-surgical treatment of ruptured lumbar disc herniation]

OBJECTIVE

To investigate the short-term and mid-term efficacy with non-surgical treatment and to predict the long-term outcomes of ruptured lumbar disc herniation.

METHODS

From February 2011 to February 2014, 75 patients with single-segment ruptured lumbar disc herniation treated by non-surgical therapy were selected for prospective study. There were 53 males and 22 females, aged from 18 to 58 (35.62±9.96) years old. The course of disease was from 5 days to 6 months, with an average of (46.45±40.66) days. The lesions were located at L_3,4 in 4 cases, at L_4,5 in 29 cases, at L₅S₁ in 42 cases. Radiation pain in 46 cases on the left and 29 cases on the right. The JOA score, straight leg raising test angle and finger-to-ground distance were assessed pretreatment and at 3 months, 6 months, 1 year, 2 years and 5 years after treatment. The improvement rate of JOA at the final follow up (5 years after treatment) was calculated and the curative effect according to JOA score was evaluated;the volume change of protrusion before treatment and at the final follow-up (5 years after treatment) was analyzed, the volume absorption rate of protrusion was calculated and the absorption of protrusion was observed;the relationship between the improvement rate of JOA and the absorption rate of protrusion were analyzed.

RESULTS

Seventy one patients were finally followed up at 5 years after non surgical treatment. The JOA score, straight leg raising test angle and finger to ground distance at 3 months, 6 months, 1 year, 2 years and 5 years after treatment were significantly improved (P<0.05). There was no significant difference in JOA scores between 5 years and 6 months after treatment, 5 and 2 years after treatment, and 2 years and 6 months after treatment (P>0.05). There was significant differencein other time points (P<0.05). The results of the straight leg raising test angle and the finger-to-ground distance were similar to the JOA scores. The improvement rate of JOA score was (62.69± 2.47)% at the final follow-up. According to JOA score, the results were excellent in 26 cases, good in 26 cases, fair in 14 cases, poor in 5 cases, and the excellent and good rate was 73.24%. The volume of protrusion decreased from (1 981.73±588.72) mm³ to (1 011.82±395.47) mm3, the total absorption rate was (45.65±2.83)%, the protrusion was obviously absorbed in 24 cases, partially absorbed in 26 cases, not absorbed in 19 cases, and increased in 2 cases. It was found that there was a positive correlation between improvement rate of JOA scores and protrusion absorption rate at 5 years after non surgical treatment (r= 0.679, P<0.001).

CONCLUSION

Non-surgical treatment of ruptured lumbar disc herniation can achieve good results, clear the characteristics of the ruptured lumbar disc herniation and prognosis, and some patients have "reabsorption" phenomenon.

Long-term evaluation of three-dimensional volumetric changes of augmented severely atrophic maxilla by anterior iliac crest bone grafting

PURPOSE

The purpose of this study was to evaluate long-term three-dimensional graft resorption following reconstruction of the severely atrophic maxilla with anterior iliac crest bone grafting.

METHODS

Twenty-two patients (13 males), who underwent autogenous bone grafting and implant placement to their severely atrophic maxillary alveolar ridges were identified and included in the study. Pre- and postoperative cone-beam computed tomography (CBCT) scans of 40 recipient grafting sites were evaluated to calculate volumetric changes over time. CBCT scans were performed preoperatively (V0) and one week (V1), three months (V2), one year (V3), and three years (V4) following the augmentation operation.

RESULTS

The average graft resorption from V1 to V2, V1 to V3, and V1 to V4 was 31.42%, 33.96%, and 37.96%, respectively. Initial graft volume reduction within the first three months was statistically higher compared to other postoperative periods (P<0.013). The rate of resorption reduced slightly from the third month of the surgery (V2) (P>0.013). There was no statistical difference between resorption volume and gender, type of prosthesis, the presence of vestibuloplasty, or patient age (P>0.05).

CONCLUSION

The overall success rate of the iliac bone block grafts was found to be high. The volumetric resorption rates associated with the graft were favourable for the reconstruction of the maxilla and for permitting the placement of dental implants three months after augmentation. The highest graft resorption was found at the third postoperative month. Placement and loading of the implants reduced the resorption rate slightly over time.