Where Do We Stand on Cervical Spine Immobilisation? A Questionnaire among Prehospital Staff

Background: Cervical collars (CC) are routinely used in prehospital trauma treatment. However, over the past years, their application was discussed more critically since they increase intravenous pressure due to reduced venous drainage and the possibility of secondary cervical spine injury. Guidelines have been adjusted accordingly. The question is how efficient has this been put into practice, and how good, as well as up to date, is the knowledge of prehospital emergency medicine personnel about indications on cervical spine immobilisation? Methods: A 15-item questionnaire regarding the self-evaluation and result checking of the right indications for the use of a cervical collar in the prehospital setting was sent to paramedics and emergency doctors in Germany. Two hundred and nineteen completed surveys were statistically analysed. Results: Mean age of the participants was 30.45 ± 8.8. 72% were male. Regarding subjective safety, the appropriate indication of CC participants reached 79.8 ± 19.5 on a metric scale from 0 (no safety) to 100 (full safety). Mean right answers were as follows: Ambulance man (RS) 0.78 ± 0.84, paramedic (RA) 0.9 ± 0.74, paramedic (NFS) 1.03 ± 0.83 and emergency doctor (ED) 1.75 ± 1.06 (p = 0.013, Kruskal-Wallis Test). Participants who estimated their knowledge < 85% had 0.83 ± 0.8 right answers, and > 85% had 1.14 ± 0.9 right answers. Conclusions: Rational spine immobilisation is still necessary in severely injured patients. This study highlights the importance of continuing education using ongoing training, lectures or online learning with a questionnaire as a monitor for success to ensure the transfer of evidence-based medicine into daily practice.

[Osteoporotic vertebral fractures of the thoracic and lumbar spine]

The frequency of osteoporotic vertebral fractures in the clinical routine is increasing due to the demographic change. They are the most frequent fractures associated with osteoporosis and affect an especially morbid and vulnerable group of patients. These fractures often occur after minor trauma or spontaneously. Pain is the predominant symptom, whereas mechanical stability is mostly sufficient, in comparison to vertebral fractures after high-energy trauma, and is not a predominant indication for surgery. These fractures can be described using the classification for fractures associated with osteoporosis and the corresponding treatment recommendations are guided by them. Besides the specific treatment of osteoporotic vertebral fractures, a holistic treatment of patients taking pre-existing comorbidities into consideration is decisive. A mobilization as quickly as possible and treatment of the underlying osteoporosis are important to prevent further fractures.

Advantage of ostarine over raloxifene and their combined treatments for muscle of estrogen-deficient rats

PURPOSE

Selective androgen (ostarine, OST) and estrogen (raloxifene, RAL) receptor modulators with improved tissue selectivity have been developed as alternatives to hormone replacement therapy. We investigated the combined effects of OST and RAL on muscle tissue in an estrogen-deficient rat model of postmenopausal conditions.

METHODS

Three-month-old Sprague Dawley rats were divided into groups: (1) untreated non-ovariectomized rats (Non-OVX), (2) untreated ovariectomized rats (OVX), (3) OVX rats treated with OST, (4) OVX rats treated with RAL, (5) OVX rats treated with OST and RAL. Both compounds were administered in the diet. The average dose received was 0.6 ± 0.1 mg for OST and 11.1 ± 1.2 mg for RAL per kg body weight/day. After thirteen weeks, rat activity, muscle weight, structure, gene expression, and serum markers were analyzed.

RESULTS

OST increased muscle weight, capillary ratio, insulin-like growth factor 1 (Igf-1) expression, serum phosphorus, uterine weight. RAL decreased muscle weight, capillary ratio, food intake, serum calcium and increased Igf-1 and Myostatin expression, serum follicle stimulating hormone (FSH). OST + RAL increased muscle nucleus ratio, uterine weight, serum phosphorus, FSH and luteinizing hormone and decreased body and muscle weight, serum calcium. Neither treatment changed muscle fiber size. OVX increased body and muscle weight, decreased uterine weight, serum calcium and magnesium.

CONCLUSION

OST had beneficial effects on muscle in OVX rats. Side effects of OST on the uterus and serum electrolytes should be considered before using it for therapeutic purposes. RAL and RAL + OST had less effect on muscle and showed endocrinological side effects on pituitary-gonadal axis.

Standard imaging in the emergency department in geriatric patients with immobilizing pelvic pain after low-energy trauma or without trauma: X-ray vs. computed tomography

PURPOSE

Geriatric pelvic ring injuries, evaluated solely by X-ray, are often misclassified or even missed. This can result in prolonged immobilization and persistent pelvic pain. The aim of this study was to assess the sensitivity and specificity of X-ray imaging in patients aged ≥ 70 years with immobilizing pelvic pain.

METHODS

107 geriatric patients (23 males, 84 females) with immobilizing pain after traumatic or atraumatic causes were included in this retrospective study. 91 patients had an anteroposterior (AP) X-ray of the pelvis and after that a computed tomography (CT) of the pelvis. All patients were treated in a level 1 trauma center from December 2018 to September 2020. The mean age was 83.07 ± 6.08 years.

RESULTS

The overall evaluation of the diagnostic performance of AP Pelvic X-ray imaging in the study population compared to the CT pelvis ("gold standard") resulted in a sensitivity of (2.7 %) and a specificity of (94.4 %). Specific for pelvic ring fractures in the study population there was a sensitivity of (3.4 %) and a specificity of (94.4 %).

CONCLUSION

The results highlights issues with the AP Pelvic X-ray as the diagnostic tool of choice in this study population, confirming the findings of previous studies on the underestimated problem of osteoporotic pelvic ring fractures in geriatric patients. This again confirms the need for a new optimized diagnostic algorithm, which takes into account the differences of the orthogeriatric patient cohort.

Can You Feel it? - Correlation Between Intraoperatively Perceived Bone Quality and Objectively Measured Bone Mineral Density

STUDY DESIGN

clinical study.

OBJECTIVES

Loosening of pedicle screws is a frequent complication in patients with osteoporosis. The indication for additional stabilization, such as cement augmentation, is more often based on the subjective intraoperative feeling of the surgeon than on a preoperative bone mineral density (BMD) measurement. Aim was to evaluate the correlation of the intraoperative perceived bone quality in comparison to the objectively measured BMD.

METHODS

A total of 62 patients undergoing dorsal stabilization using pedicle screws at a level-1 trauma center were analyzed. The preoperative CT scan measured each instrumented vertebra's pedicle size and BMD. During the surgery, the perceived screw stability was graded by the respective surgeon for each screw.

RESULTS

204 vertebral bodies were evaluated. Looking at all implanted screws a significant correlation between the measured BMD and the perceived screw stability was found (Resident r = .450; R2 = .202; P < .001/Attending r = .364; R2 = .133; P < .001), but there was no significant correlation in the osteoporotic patients (Resident P = .148 / Attending P = .907). The evaluation of the screws implanted in osteoporotic vertebrae showed that the surgeons considered a total of 31% of these screws to be sufficiently stable.

CONCLUSIONS

There was no significant correlation between the measured BMD and the perceived pedicle screw stability in the group with osteopenic / osteoporotic bone (<100 mg/cm³). The results indicate that it is not possible to reliably determine the bone quality and the resulting screw stability in patients with reduced BMD. The preoperative measurement of the BMD should become a crucial part of preoperative planning.

Reconstruction of an Extensive Segmental Radial Shaft Bone Defect by Vascularized 3D-Printed Graft Cage

We report here a 46-year-old male patient with a 14 cm segmental bone defect of the radial shaft after third degree open infected fracture caused by a shrapnel injury. The patient underwent fixed-angle plate osteosynthesis and bone reconstruction of the radial shaft by a vascularized 3D-printed graft cage, including plastic coverage with a latissimus dorsi flap and an additional central vascular pedicle. Bony reconstruction of segmental defects still represents a major challenge in musculo-skeletal surgery. Thereby, 3D-printed scaffolds or graft cages display a new treatment option for bone restoration. As missing vascularization sets the limits for the treatment of large-volume bone defects by 3D-printed scaffolds, in the present case, we firstly describe the reconstruction of an extensive radial shaft bone defect by using a graft cage with additional vascularization.

[Comparison of planimetric CT‑based volumetry with simplified models for determining the size of intrapelvic hematomas due to pelvic fractures in emergency room diagnostics]

BACKGROUND

Bleeding in the pelvis can lead to a circulatory problem. The widely used whole-body computed tomography (WBCT) scan in the context of treatment in the trauma resuscitation unit (TRU) can give an idea of the source of bleeding (arterial vs. venous/osseous); however, the volume determination of an intrapelvic hematoma by volumetric planimetry cannot be used for a quick estimation of the blood loss. Simplified measurement techniques using geometric models should be used to estimate the extent of bleeding complications.

OBJECTIVE

To determine whether simplified geometric models can be used to quickly and reliably determine intrapelvic hematoma volume in fractures type Tile B/C during emergency room diagnostics or whether the time-consuming planimetric method must always be used.

MATERIAL AND METHODS

Retrospectively, 42 intrapelvic hemorrhages after pelvic fractures Tile B + C (n = 8:B, 34:C) at two trauma centers in Germany were selected (66% men, 33% women; mean age 42 ± 20 years) and the CT scans obtained during the initial trauma scan were analyzed in more detail. The CT datasets of the included patients with 1-5 mm slice thickness were available for analysis. By area labelling (ROIs) of the hemorrhage areas in the individual slice images, the volume was calculated by CT volumetrically. Comparatively, volumes were calculated using simplified geometric figures (cuboid, ellipsoid, Kothari). A correction factor was determined by calculating the deviation of the volumes of the geometric models from the planimetrically determined hematoma size.

RESULTS AND DISCUSSION

The median planimetric bleeding volume in the total collective was 1710 ml (10-7152 ml). Relevant pelvic bleeding with a total volume > 100 ml existed in 25 patients. In 42.86% the volume was overestimated in the cuboid model and in 13 cases (30.95%) there was a significant underestimation to the planimetrically measured volume. Thus, we excluded this volume model. In the models ellipsoid and measuring method according to Kothari, an approximation to the planimetrically determined volume could be achieved with a correction factor calculated via a multiple linear regression analysis. The time-saving and approximate quantification of the hematoma volume using a modified ellipsoidal calculation according to Kothari makes it possible to assess the extent of bleeding in the pelvis after trauma if there are signs of a C-problem. This measurement method, as a simple reproducible metric, could be embedded in trauma resuscitation units (TRU) in the future.

Lessons learned from biomechanical studies on cephalomedullary nails for the management of intertrochanteric fractures. A scoping review

INTRODUCTION

The increasing socioeconomic need for optimal treatment of hip fractures in combination with the high diversity of available implants has raised numerous biomechanical questions. This study aims to provide a comprehensive overview of biomechanical research on the treatment of intertrochanteric fractures using cephalomedullary devices.

METHODS

Following the PRISMA-P guidelines, a systematic literature search was performed on 31.12.2022. The databases PubMed/MEDLINE and Web of Science were searched. Scientific papers published between 01.01.2000 - 31.12.2022 were included when they reported data on implant properties related to the biomechanical stability for intertrochanteric fractures. Data extraction was undertaken using a synthesis approach, gathering data on criteria of implants, sample size, fracture type, bone material, and study results.

RESULTS

The initial search identified a total of 1459 research papers, out of which forty-three papers were considered for final analysis. Due to the heterogeneous methods and parameters used in the included studies, meta-analysis was not feasible. A comprehensive assessment of implant characteristics and outcome parameters was conducted through biomechanical analysis. Various factors such as proximal and distal locking, nail diameter and length, fracture model, and bone material were thoroughly evaluated.

CONCLUSION

This scoping review highlights the need for standardization in biomechanical studies on intertrochanteric fractures to ensure reliable and comparable results. Strategies such as avoiding varus, maintaining a sufficient tip-apex-distance, cement augmentation, and optimizing lesser trochanteric osteosynthesis enhance construct stability. Synthetic alternatives may offer advantages over cadaveric bone. Further research and meta-analyses are required to establish standardized protocols and enhance reliability.

Effects of ligandrol as a selective androgen receptor modulator in a rat model for osteoporosis

INTRODUCTION

The selective androgen receptor modulator ligandrol (LGD-4033 or VK5211) has been shown to improve muscle tissue. In the present study, the effect of ligandrol on bone tissue was investigated in ovariectomized rat model.

MATERIALS AND METHODS

Three-month-old Sprague Dawley rats were either ovariectomized (OVX, n = 60) or left intact (NON-OVX, n = 15). After 9 weeks, OVX rats were divided into four groups: untreated OVX (n = 15) group and three OVX groups (each of 15 rats) treated with ligandrol orally at doses of 0.03, 0.3, or 3 mg/kg body weight. After five weeks, lumbar vertebral bodies (L), tibiae, and femora were examined using micro-computed tomographical, biomechanical, ashing, and gene expression analyses.

RESULTS

In the 3-mg ligandrol group, bone structural properties were improved (trabecular number: 38 ± 8 vs. 35 ± 7 (femur), 26 ± 7 vs. 22 ± 6 (L), 12 ± 5 vs. 6 ± 3 (tibia) and serum phosphorus levels (1.81 ± 0.17 vs.1.41 ± 0.17 mmol/l), uterus (0.43 ± 0.04 vs. 0.11 ± 0.02 g), and heart (1.13 ± 0.11 vs. 1.01 ± 0.08 g) weights were increased compared to the OVX group. Biomechanical parameters were not changed. Low and medium doses did not affect bone tissue and had fewer side effects. Body weight and food intake were not affected by ligandrol; OVX led to an increase in these parameters and worsened all bone parameters.

CONCLUSION

Ligandrol at high dose showed a subtle anabolic effect on structural properties without any improvement in biomechanical properties of osteoporotic bones. Considering side effects of ligandrol at this dose, its further investigation for the therapy of postmenopausal osteoporosis should be reevaluated.

The pelvic vascular injury score (P-VIS): a prehospital instrument to detect significant vascular injury in pelvic fractures

PURPOSE

The purpose of this study was to identify predictive factors for peri-pelvic vascular injury in patients with pelvic fractures and to incorporate these factors into a pelvic vascular injury score (P-VIS) to detect severe bleeding during the prehospital trauma management.

METHODS

To identify potential predictive factors, data were taken (1) of a Level I Trauma Centre with 467 patients (ISS ≥ 16 and AISPelvis ≥ 3). Analysis including patient's charts and digital recordings, radiographical diagnostics, mechanism and pattern of injury as well as the vascular bleeding source was performed. Statistical analysis was performed descriptively and through inference statistical calculation. To further analyse the predictive factors and finally develop the score, a 10-year time period (2012-2021) of (2) the TraumaRegister DGU® (TR-DGU) was used in a second step. Relevant peri-pelvic bleeding in patients with AISPelvis ≥ 3 (N = 9227) was defined as a combination of the following entities (target group PVITR-DGU N = 2090; 22.7%): pelvic fracture with significant bleeding (> 20% of blood volume), Injury of the iliac or femoral artery or blood transfusion of ≥ 6 units (pRBC) prior to ICU admission. The multivariate analysis revealed nine items that constitute the pelvic vascular injury score (P-VIS).

RESULTS

In study (1), 467 blunt pelvic trauma patients were included of which 24 (PVI) were presented with significant vascular injury (PVI, N = 24; control (C, N = 443). Patients with pelvic fractures and vascular injury showed a higher ISS, lower haemoglobin at admission and lower blood pressure. Their mortality rate was higher (PVI: 17.4%, C: 10.3%). In the defining and validating process of the score within the TR-DGU, 9227 patients met the inclusion criteria. 2090 patients showed significant peripelvic vascular injury (PVITR-DGU), the remaining 7137 formed the control group (CTR-DGU). Nine predictive parameters for peripelvic vascular injury constituted the peripelvic vascular injury score (P-VIS): age ≥ 70 years, high-energy-trauma, penetrating trauma/open pelvic injury, shock index ≥ 1, cardio-pulmonary-resuscitation (CPR), substitution of > 1 l fluid, intubation, necessity of catecholamine substitution, remaining shock (≤ 90 mmHg) under therapy. The multi-dimensional scoring system leads to an ordinal scaled rating according to the probability of the presence of a vascular injury. A score of ≥ 3 points described the peripelvic vascular injury as probable, a result of ≥ 6 points identified a most likely vascular injury and a score of 9 points identified an apparent peripelvic vascular injury. Reapplying this score to the study population a median score of 5 points (range 3-8) (PVI) and a median score of 2 points (range 0-3) (C) (p < 0.001). The OR for peripelvic vascular injury was 24.3 for the patients who scored > 3 points vs. ≤ 2 points. The TR-DGU data set verified these findings (median of 2 points in CTR-DGU vs. median of 3 points with in PVITR-DGU).

CONCLUSION

The pelvic vascular injury score (P-VIS) allows an initial risk assessment for the presence of a vascular injury in patients with unstable pelvic injury. Thus, the management of these patients can be positively influenced at a very early stage, prehospital resuscitation performed safely targeted and further resources can be activated in the final treating Trauma Centre.

Treatment of osteoporosis using a selective androgen receptor modulator ostarine in an orchiectomized rat model

PURPOSE

The selective androgen receptor modulator ostarine has been shown to have advantageous effects on skeletal tissue properties, reducing muscle wasting and improving physical function in males. However, data on effects in male osteoporosis remain limited. In this study, the effects of ostarine on osteoporotic bone were evaluated in a rat model of male osteoporosis and compared with those of testosterone treatments.

METHODS

Eight-month-old male Sprague-Dawley rats were either non-orchiectomized to serve as a healthy control (Non-Orx, Group 1) or orchiectomized (Orx, Groups 2-6) and then grouped (n = 15/group): (1) Non-Orx, (2) Orx, (3) Ostarine Therapy, (4) Testosterone Therapy, (5) Ostarine Prophylaxis and (6) Testosterone Prophylaxis. Prophylaxis treatments started directly after orchiectomy and continued for 18 weeks, whereas Therapy treatments were initiated 12 weeks after Orx. Ostarine and Testosterone were applied orally at daily doses of 0.4 and 50 mg/kg body weight, respectively. The lumbar vertebral bodies and femora were analyzed using biomechanical, micro-CT, ashing, and gene expression analyses.

RESULTS

Ostarine Prophylaxis showed positive effects in preventing osteoporotic changes in cortical and trabecular bone (femoral trabecular density: 26.01 ± 9.1% vs. 20.75 ± 1.2% in Orx and in L4: 16.3 ± 7.3% vs 11.8 ± 2.9% in Orx); biomechanical parameters were not affected; prostate weight was increased (0.62 ± 0.13 g vs 0.18 ± 0.07 g in Orx). Ostarine Therapy increased solely the cortical density of the femur (1.25 ± 0.03 g/cm3 vs. 1.18 ± 0.04 g/cm3 in Orx); other bone parameters remained unaffected. Testosteron Prophylaxis positively influenced cortical density in femur (1.24 ± 0.05 g/cm3 vs. 1.18 ± 0.04 g/cm3 in Orx); Test. Therapy did not change any bony parameters.

CONCLUSION

Ostarine Prophylaxis could be further investigated as a preventative treatment for male osteoporosis, but an androgenic effect on the prostate should be taken into consideration, and combination therapies with other anti-osteoporosis agents could be considered.

Predictive factors for docking site procedure in bone transport for large lower extremity segmental defects

BACKGROUND

Segmental bone transport is a common technique for treating large segmental bone defects. However, a docking site procedure is often necessary in segmental bone transport. To date, no prognostic factors for the need of docking site procedure have been reported. Thus, the decision is often made at random, based on the surgeon's subjective judgment and experience. The aim of this study was to identify prognostic factors for the need of docking site operation.

METHODS

Patients with segmental bone transport in lower extremity bone defects were included regardless of age, aetiology, and defect size. We excluded patients undergoing treatments that were not yet completed, and those who discontinued therapy by any reason. The need for docking site operation was modelled with logistical and linear regression as well as univariate analysis of variances (ANOVA). Receiver operating characteristics (ROC) curve analysis was also performed.

RESULTS

Twenty-seven patients from age 12 to 74 years (mean age: 39.07 ± 18.20 years) were included. The mean defect size was 76.39 ± 41.10 mm. The duration of transport (days) showed a significant influence (p = 0.049, 95%CI: 1.00-1.02) on the need for docking site operation. No other significant influences were detected.

CONCLUSION

A link between the duration of transport and the need for docking site operation was detected. Our data showed that if a threshold of about 188 days is exceeded, docking surgery should be considered.

Retrospective In-Hospital Mortality Analysis of GeriatricPatients Treated in a Level 1 Trauma Center

The aim of this study is to determine the critical time intervals and influencing covariates for in-hospital mortality in geriatric trauma and orthopedic patients. During a period of five years, we retrospectively review patients aged > 60 years who were hospitalized at the Department of Trauma, Orthopedic, and Plastic Surgery. The primary outcome is the mean time to death. Survival analysis is performed using an accelerated failure time model. A total of 5388 patients are included in the analysis. Two-thirds underwent surgery (n = 3497, 65%) and one-third were conservatively treated (n = 1891, 35%). The in-hospital mortality rate is 3.1% (n = 168; surgery, n = 112; conservative, n = 56). The mean time to death is 23.3 days (±18.8) after admission in the surgery group and 11.3 days (±12.5) in the conservative treatment group. The greatest accelerating effect on mortality is found in the intensive care unit (16.52, p < 0.001). We are able to identify a critical time interval for in-hospital mortality between days 11 and 23. The day of death on weekend days/holidays, hospitalization for conservative treatment, and treatment at the intensive care unit significantly increase the risk of in-hospital mortality. Early mobilization and a short hospitalization duration seem to be of major importance in fragile patients.

[Biological reconstruction of large bone defects : Masquelet technique and new procedures]

Extensive diaphyseal and metaphyseal bone defects continue to pose a major challenge for orthopedic trauma surgeons. Various treatment options have been described for the biological reconstruction of these defects. The most frequently used methods are bone segment transport, the Masquelet technique and 3D printed scaffolds. As far as the Masquelet technique is concerned, in the first stage spacers, such as polymethyl methacrylate (PMMA), calcium sulfate or polypropylene are inserted into the bone defects to induce a foreign body membrane. In the second stage the bone defect surrounded by the induced membrane is filled with autologous cancellous bone. The time interval between the first and second interventions is usually 4-8 weeks whereby the induced membranes do not lose their bioactivity even with a latency period longer than 8 weeks. Three-dimensional printed scaffolds are increasingly used but large clinical studies are lacking in order to show the exact role of this procedure in the reconstruction of bone defects.

[Interdisciplinary extremity board in the treatment of complex injuries]

BACKGROUND

Interdisciplinary case conferences are well-established in the field of oncology in order to provide the best possible treatment for patients with complex disease patterns which overlap several disciplines.

METHODS

After studying the available literature the aims, indications, frequency, patient enrolment and documentation modalities, disciplines necessary to create the reconstruction plan and evaluation parameters of the board, were agreed in an interdisciplinary discussion among colleagues. The utilization of the extremity board and demographic features of the cases presented in the extremity board within the first 6 months were subsequently descriptively analyzed.

RESULTS

The agreed primary aim of an extremity board is the timely and transparent preparation of a high-quality holistic reconstruction plan for optimized treatment of a challenging patient collective with complex injuries of the extremities. Decisive interfaces of an extremity board are the participation of interdisciplinary disciplines, established enrolment and documentation modalities and a longitudinal analysis of parameters of the acute medical treatment, the long-term function and quality of life of those affected. The patient collective so far mostly includes men under 40 years old with traumatic soft tissue defects and combined injuries. On average, reconstruction plans for 1-2 patients were approved in an interdisciplinary team per session.

CONCLUSION

The extremity board serves as a platform for coordinated planning of treatment for patients with complex injuries. The limited personnel and time resources represent the greatest challenge for the successful implementation. The extremity board enables a high degree of interdisciplinary networking. The digital registration and documentation modality within the internal hospital documentation system is of utmost relevance. The preparation of the reconstruction plan is of decisive importance for the qualitative success of treatment and the restoration of function. The longitudinal analysis of appropriate parameters is imperative to measure the quality of treatment.

Validation of direct CT measurement of malrotation in femoral neck fractures: A bone model study

BACKGROUND

While postoperative malrotation in the subtrochanteric region is a well-known problem, malrotation after osteosynthesis in proximal femoral fractures has not been extensively studied. In this context, many methods for perioperatively assessment of femoral torsion have been described, but none of them is applicable in the basicervical region of the proximal femur. As an important difference in femoral neck fractures, the discontinuous neck fails to serve as a significant "pointer" for measurements and malfunctions to be placed in relation to the condylar plane. Considering postoperative maltorsion at any location as a substantial negative effect on patients' outcome and functional expectations, precise and patient-friendly rotation measurement standards in femoral neck fractures are desired in clinical practice. Recently, a novel computed tomography (CT) based geometric technique was described named "direct measurement" with promising results covering this diagnostic disparity, but still requires validation. Thus, we aimed to validate the previously described technique using a controlled range of displacement in a femoral neck fracture Sawbone® model.

METHODS AND FINDINGS

A goniometer was designed to set retro- and anteversion of the proximal femur in a reproducible manner. Prospectively, all femurs underwent a CT scan and were measured 3D for displacement. The interclass correlation between the CT measurements and the goniometer measurements was calculated and was found to be very high (1.00, 95% confidence interval: 0.99-1.00; p < 0.001). For the mean of all measurements, the Pearson's correlation was 1.00 (p < 0.001). No significant differences in the measurements of both investigators were observed, with 20° of retroversion not significant (-1.20 ± 1.71; 95% confidence interval: -2.43-0.03; p = 0.054).

CONCLUSION

This CT-based 3D measurement technique may allow for perioperative malrotation assessment in basicervical femoral neck fractures and appears to be feasible in femoral neck fractures when it comes to rare cases of osteosynthesis. Further investigations are still needed to define the thresholds of malrotation provoking functional impairment after osteosynthesis in basicervical femoral neck fractures.

A combined treatment with selective androgen and estrogen receptor modulators prevents bone loss in orchiectomized rats

PURPOSE

Enobosarm (EN), a selective androgen receptor modulator and raloxifene (RAL), a selective estrogen receptor modulator, have been shown to improve bone tissue in osteoporotic males. The present study evaluated the effects of a combination therapy of EN and RAL on bone properties in orchiectomized rats compared to the respective single treatments.

METHODS

Eight-month-old male Sprague-Dawley rats were either left intact (Non-Orx) or orchiectomized (Orx). The Orx rats were divided into four groups (n = 15 each): 1) Orx, 2) EN treatment (Orx + EN), 3) RAL treatment (Orx + RAL), 4) combined treatment (Orx + EN + RAL). EN and RAL (0.4 mg and 7 mg/kg body weight/day) were applied immediately after Orx with a soy-free pelleted diet for up to 18 weeks. The lumbar spine and femora were examined by micro-CT, biomechanical, histomorphological, ashing, and gene expression analyses.

RESULTS

EN exhibited an anabolic effect on bone, improving some of its parameters in Orx rats, but did not affect biomechanical properties. RAL exhibited antiresorptive activity, maintaining the biomechanical and trabecular parameters of Orx rats at the levels of Non-Orx rats. EN + RAL exerted a stronger effect than the single treatments, improving most of the bone parameters. Liver weight increased after all treatments; the kidney, prostate, and levator ani muscle weights increased after EN and EN + RAL treatments. BW was reduced due to a decreased food intake in the Orx + RAL group and due a reduced visceral fat weight in the Orx + EN + RAL group.

CONCLUSION

The EN + RAL treatment appeared to be promising in preventing male osteoporosis, but given the observed side effects on liver, kidney, and prostate weights, it requires further investigation.

[Does navigation still have a value in trauma surgery?]

BACKGROUND

Navigation systems are supposed to increase precision and support surgeons while they perform certain interventions. 2D, or nowadays 3D, systems are used in image-based approaches. Image-free navigation uses 3D printing.

INDICATIONS

There are several studies on navigation procedures in trauma surgery. In contrast to limb surgery, the use of 3D navigation in pelvic and spine surgery is already well established. Navigation is especially regularly used to treat fractures of the posterior pelvic ring and for posterior stabilization of the cervical spine.

REQUIREMENTS

To be able to utilize navigation systems optimally, the learning curve should be completed, and the technique should be used regularly. In addition, the surgeon should know the surgical technique without navigation in order to recognize potential errors of the navigation.

ADVANTAGES AND DISADVANTAGES

Advantages include increased patient safety, reduction in radiation exposure and less invasive surgical procedures. However, among other disadvantages, initial costs are high.

Combination of selective androgen and estrogen receptor modulators in orchiectomized rats

PURPOSE

Selective androgen and estrogen receptor modulators, ostarine (OST) and raloxifen (RAL), reportedly improve muscle tissue and offer therapeutic approaches to muscle maintenance in the elderly. The present study evaluated the effects of OST and RAL and their combination on musculoskeletal tissue in orchiectomized rats.

METHODS

Eight-month-old Sprague Dawley rats were analyzed. Experiment I: (1) Untreated non-orchiectomized rats (Non-ORX), (2) untreated orchiectomized rats (ORX), (3) ORX rats treated with OST during weeks 0-18 (OST-P), (4) ORX rats treated with OST during weeks 12-18 (OST-T). Experiment II: 1) Non-ORX, (2) ORX, 3) OST-P, (4) ORX rats treated with RAL, during weeks 0-18 (RAL-P), 5) ORX rats treated with OST + RAL, weeks 0-18 (OST + RAL-P). The average daily doses of OST and RAL were 0.4 and 7 mg/kg body weight (BW). Weight, fiber size, and capillarization of muscles, gene expression, serum markers and the lumbar vertebral body were analyzed.

RESULTS

OST-P exerted favorable effects on muscle weight, expression of myostatin and insulin growth factor-1, but increased prostate weight. OST-T partially improved muscle parameters, showing less effect on the prostate. RAL-P did not show anabolic effects on muscles but improved body constitution by reducing abdominal area, food intake, and BW. OST + RAL-P had an anabolic impact on muscle, reduced androgenic effect on the prostate, and normalized food intake. OST and RAL improved osteoporotic bone.

CONCLUSIONS

The OST + RAL treatment appeared to be a promising option in the treatment of androgen-deficient conditions and showed fewer side effects than the respective single treatments.

Bone defect treatment: does the type and properties of the spacer affect the induction of Masquelet membrane? Evidence today

PURPOSE

High clinical success rates have been reported with the Masquelet technique in the treatment of traumatic bone loss. An increasing number of studies suggest that various factors can influence the properties of induced membranes. Goal of this systematic review is to answer the following questions: (1) which are the ideal spacer properties (material, surface topography, antibiotic supplementation) to booster the quality and osteogenic potential of induced membranes? (2) what is the ideal time to perform the second-stage operation?

METHODS

A systematic search using the keywords "((Masquelet) OR (Induced Periosteum)) AND ((Spacer) OR (Time))" was performed in PubMed, Embase and Cochrane Library according to PRISMA guidelines. Studies published up to the 23rd of February 2022 were included and assessed independently by two reviewers.

RESULTS

Thirteen animal and 1 clinical studies were identified to address the above questions. Spacer materials used were PMMA, silicone, titanium, polypropylene, PVA, PCL and calcium sulfate. With the exception of PVA sponges, all solid materials could induce membranes. Low union rates have been reported with titanium and rough surfaced spacers. Scraping of the inner surface of the IM also increased bony union rates. In terms of the ideal timing to perform the second-stage evidence suggests that membranes older than 8 weeks continue to have regenerative capacities similar to younger ones.

CONCLUSION

Membranes induced by smooth PMMA spacers loaded with low concentrations of antibiotics showed powerful osteogenic properties. Other materials such as Polypropylene or Calcium sulfate can also be used with good results. Despite current recommendation to perform the second stage operation in 4-8 weeks, membranes older than 8 weeks seem to have similar regenerative capacities to younger ones.

[Common infectious challenges of the thoracic and lumbar spine : Spondylodiscitis and postoperative wound infection]

Spondylodiscitis and postoperative wound infections are the most frequent infectious diseases of the thoracic and lumbar spine. Every spinal surgeon will come into contact with such patients during his or her career. Knowledge particularly of the diagnostics, conservative and surgical treatment as well as microbiological considerations of antibiotic treatment are therefore of particular importance and are explained in this article.

Long-term Quality of Life after Fusion of the Ventral Thoracic and Lumbar Spine

BACKGROUND

 Cage implantations and autologous pelvic bone grafts are common surgical procedures to fuse the spine in cases of spinal disorders such as traumatic fractures or degenerative diseases. These surgical methods are designed to stably readjust the spine and to prevent late detrimental effects such as pain or increasing kyphosis. Benefits of these surgical interventions have been evaluated, but the long-term well-being of patients after the respective treatments has not yet been examined. This study was designed to evaluate the clinical outcome for patients who received iliac crest or cage implantations.

MATERIAL AND METHODS

 Forty-six patients with traumatic fractures after they obtained an anterior fusion in the thoracic or lumbar spine (12 cages; mean age: 54.08 years; 34 pelvic bone grafts; mean age: 42.18 years) were asked to participate in the survey using a precast questionnaire according the Visual Analog Scale (VAS) Spine Score. Twenty-nine of them provided the data requested.

RESULTS

 Evaluation of the VAS scores of the patients, reporting at least 1 year after the surgery, revealed that cage implantations led to significantly better results with respect to all aspects of their daily life such as pain sensing, capability to undertake physical activities and exercise as compared with patients with autologous pelvic bone graft. Patients with autologous pelvic bone graft treatment reported a particularly poor overall satisfaction level concerning their long-term well-being.

CONCLUSIONS

 Patients with cage implantation reported a higher degree of long-term well-being. The data provide evidence for a positive impact on the postsurgery quality of life after cage implantation.

Cage or Pelvic Graft-Study on Bony Fusion of the Ventral Thoracic and Lumbar Spine in Traumatic Vertebral Fractures

Background and Objectives: Stabilization of the spine by cage implantation or autologous pelvic bone graft are surgical methods for the treatment of traumatic spine fractures. These methods serve to stably re-adjust the spine and to prevent late detrimental effects such as pain or increasing kyphosis. They both involve ventral interventions using interbody fusion to replace the intervertebral disc space between the vertebral bodies either by cages or autologous pelvic bone grafts. We examined which of these methods serves the patients better in terms of bone fusion and the long-term clinical outcome. Materials and Methods: Forty-six patients with traumatic fractures (12 cages; mean age: 54.08/34 pelvic bone grafts; mean age: 42.18) who received an anterior fusion in the thoracic or lumbar spine were included in the study. Postoperative X-ray images were evaluated, and fusion of the stabilized segment was inspected by two experienced spine surgeons. The time to discharge from hospital and gender differences were evaluated. Results: There was a significant difference of the bone fusion rate of patients with autologous pelvic bone grafts in favor of cage implantation (p = 0.0216). Also, the stationary phase of patients who received cage implantations was clearly shorter (17.50 days vs. 23.85 days; p = 0.0089). In addition, we observed a significant gender difference with respect to the bony fusion rate in favor of females treated with cage implantations (p < 0.0001). Conclusions: Cage implantations after spinal fractures result in better bony fusion rates as compared to autologous pelvic bone grafts and a shorter stay of the patients in the hospital. Thus, we conclude that cage implantations rather than autologous pelvic bone grafts should be the preferred surgical treatment for stabilizing the spine after fracture.

Inhibition of Lipoxygenases Showed No Benefit for the Musculoskeletal System in Estrogen Deficient Rats

BACKGROUND

In previous studies, we reported the beneficial impact of two lipoxygenase-inhibitors, Baicalein and Zileuton, on osteoporotic bone in a postmenopausal rat model. Whereas subcutaneous Baicalein predominantly improved cortical bone, Zileuton enhanced vertebral and femoral trabecular bone. In this study, we aimed to reveal whether the oral administration of Baicalein caused similar effects on bone and whether a combined administration of Baicalein and Zileuton could act synergistically to ameliorate the formerly reported effects in the musculoskeletal system.

METHODS

We treated ovariectomized (OVX) female Sprague-Dawley rats either with Baicalein (10mg/kg BW), Zileuton (10mg/kg BW) or a combination of both (each 10mg/kg BW) for 13 weeks and compared with untreated OVX and NON-OVX groups (n=12-16 rats per group). Lumbar vertebral bodies and femora were analyzed. Tibiae were osteotomized, plate-stabilized (at week 8 after OVX) and likewise analyzed by biomechanical, histological, micro-computed tomographical and ashing tests. The skeletal muscle structure was analyzed.

RESULTS

Oral administration of Baicalein did not confirm the reported favorable cortical effects in neither vertebra nor femur. Zileuton showed a beneficial effect on trabecular vertebra, while the femur was negatively affected. Callus formation was enhanced by all treatments; however, its density and biomechanical properties were unaltered. Lipoxygenase inhibition did not show a beneficial effect on skeletal muscle. The combination therapy did not ameliorate OVX-induced osteoporosis but induced even more bone loss.

CONCLUSIONS

The preventive anti-osteoporotic treatments with two lipoxygenase inhibitors applied either alone or in combination showed no benefit for the musculoskeletal system in estrogen deficient rats.

Effect of Selective Androgen Receptor Modulator Enobosarm on Bone Healing in a Rat Model for Aged Male Osteoporosis

Enobosarm (ostarine, MK-2866, or GTx-024) is a non-steroidal selective androgen receptor modulator. This study evaluated the effect of various regimens of enobosarm (EN) on bone healing in an orchiectomized rat model for aged male osteoporosis and compared it to testosterone (T) treatment. Ninety eight-month-old male Sprague Dawley rats were either orchiectomized (Orx) or left intact (Non-Orx) and divided into groups (n = 15/group): (1) Non-Orx; (2) Orx; (3) Orx+T-th; (4) Orx+EN-th; (5) Orx+T-pr; and (6) Orx+EN-pr. Prophylaxis (Pr) treatments were applied immediately after Orx for up to 18 weeks. Therapy (Th) treatments were applied 12 weeks after Orx for up to 6 weeks. Bilateral tibia osteotomy with plate osteosynthesis was performed 12 weeks after Orx in all groups. EN and T were mixed with the diet; the daily dosage was 0.35 ± 0.06 and 41 ± 8 mg/kg BW, respectively. Both T treatments improved bone healing by increasing callus volume and area, bone volume and density, and cortical width; they had no effect on prostate or levator ani weight. EN-pr increased the callus area and callus density and decreased cortical density, but increased prostate weight. The effect of T-pr and T-th on bone was stronger than EN-pr. EN-th affected bone healing negatively by reducing callus density and area and delaying osteotomy bridging. Levator ani weight was increased in both EN groups. EN treatment after fracture is not advisable in aged males. EN-pr treatment as a therapy for bone healing in men could be further investigated; endocrinological side effects must be closely monitored.

The Selective Androgen Receptor Modulator Ostarine Improves Bone Healing in Ovariectomized Rats

Non-steroidal selective androgen receptor modulators, including ostarine, have been developed as an alternative to steroidal hormones. Ostarine has shown a beneficial effect on bone in experimental studies, but no data regarding the effect of ostarine on bone healing have yet been reported. We investigated effects of ostarine on bone healing in ovariectomized rats. Sprague-Dawley rats (3 months old) were ovariectomized (Ovx, n = 46) or left intact (Non-Ovx, n = 10). After 8 weeks, an osteotomy of the tibia metaphysis was created in all rats, and the Ovx rats were divided into four groups: untreated Ovx (n = 10) and three Ovx groups (each of 12 rats) treated with ostarine at doses of 0.04, 0.4, or 4 mg/kg BW (OS-0.04, OS-0.4, and OS-4 groups). Five weeks later, bone healing was analyzed. The OS-4 dose enhanced callus formation, increased callus density, accelerated bridging time of the osteotomy, and elevated alkaline phosphatase gene expression in callus and its protein expression in serum. In the Ovx group, most of the callus parameters were diminished. All OS treatments increased the weight of the gastrocnemius muscle, but only partly enhanced uterus weight in OS-0.4 and OS-4. Serum cholesterol level was reduced, and serum phosphorus was elevated in OS-0.04 and OS-4. Ostarine appeared to have a positive effect on early bone healing in ovariectomized rats. Considering its favorable effect on non-osteotomized bone and muscle, this treatment could be further explored as a therapy for osteoporosis. However, possible metabolic side effects should first be evaluated.

Ostarine and Ligandrol Improve Muscle Tissue in an Ovariectomized Rat Model

In postmenopausal women, hormonal decline changes muscle function and structure. The non-steroidal selective androgen receptor modulators (SARMs) Ostarine (OS) and Ligandrol (LG) have been shown to increase muscle mass and physical function while showing a relative low risk profile. Information about their effects on muscle structure and metabolism is lacking. To analyze this, two experiments were performed using ovariectomized rats as a standard model for postmenopausal conditions. In each experiment, 3-month old Sprague-Dawley rats were divided into five groups (n = 12 to 15). One group remained intact (Non-OVX), the other four groups were ovariectomized (OVX) and remained untreated for eight (OS Experiment) or nine (LG Experiment) weeks. Thereafter, rats of three of the four OVX groups were treated with OS or LG (with doses of 0.04, 0.4, or 4 mg/kg body weight/day) for 5 weeks. Then, uterus, gastrocnemius, and soleus muscles were weighed, fiber size, capillary density, and enzyme activity (lactate dehydrogenase [LDH], citrate synthase [CS], and complex I) were analyzed. In the LG experiment, intramuscular fat content was determined in the quadriceps femoris muscle. All OS treatments resulted in a higher capillary density in the gastrocnemius and longissimus muscles compared with the Non-OVX and the OVX rats, whereas all LG treatments showed a higher capillary density compared with the Non-OVX group. Muscle fiber size and distribution patterns were not changed under either SARM. The CS activity was higher in the longissimus muscle under OS treatment. LG resulted in a higher activity of CS in the gastrocnemius and of LDH in the longissimus muscle. Both SARMs showed an uterotrophic effect, OS at 4 and 0,4 mg dosages, LG at 4 mg dosage. In sum, beneficial effect on muscle vascularization was observed for both SARMs with a stronger impact for OS. LG showed more effect on muscle metabolism. However, a higher muscle weight and intramuscular fat content observed after LG treatment (4 mg) as well as an uterotrophic effect of both SARMs at higher dosages could be considered as an unfavorable side effects and might be a limitation for their application at these dosages.

Chronic hyponatremia in patients with proximal femoral fractures after low energy trauma: A retrospective study in a level-1 trauma center

Introduction

We evaluated the prevalence and influence of chronic hyponatremia in patients with low energy trauma. We also investigated the influence of medication and diseases on hyponatremia.

Material and methods

This retrospective study included 314 cases of proximal femoral fracture due to low energy trauma. Patients were treated in the University Medical Center Goettingen within 3 years. Hyponatremia was defined as serum sodium <135 mmol/L at admission.

Results

Overall, 15.6% of patients in the low energy trauma group had hyponatremia. Among patients older than 80 years, women showed distinctly higher rates of hyponatremia (female: 16.4%; male: 5.9%). In contrast only 4.7% of patients who underwent elective hip arthroplasty showed hyponatremia. Patients on sartanes and aldosterone antagonists showed significantly higher rates of hyponatremia. Alcoholism was significantly associated with hyponatremia.

Conclusions

We confirmed a high prevalence of chronic hyponatremia in patients with fractures due to low energy trauma. Our data underscore chronic hyponatremia as a contributing factor to hip fractures. Women older than 80 have a higher risk of developing hyponatremia. Sartanes, aldosterone antagonists, and alcohol disease are associated with hyponatremia. Treating hyponatremia may decrease the risk of fracture after low energy trauma. Therefore, physicians of different specialties should focus on treatment of chronic hyponatremia to reduce the fracture rate associated with low energy trauma.

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15.6% of patients with prox. femur fracture after low energy trauma had hyponatremia.

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Hyponatremia rate in group of patients before hip arthroplasty was only 4.7%.

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Sartanes, aldosterone antagonists, and alcohol disease are associated with hyponatremia.

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Women older than 80 have a higher risk of developing hyponatremia.

Hip Fractures: Therapy, Timing, and Complication Spectrum

Objective

Investigation of the treatment of femur fractures and the type of femur fracture‐associated complications regarding timing of surgery and length of hospital stay.

Methods

In this retrospective cohort study, a total of 358 hip fractures were evaluated retrospectively from 1 January 2008 until 31 December 2010 at a level I trauma center in Germany. Inclusion criteria was age >18 years and a proximal femur fracture. Both sexes were evaluated. Mean age was 75.5 years, most patients were female (63.7%). Intervention was the operative treatment of proximal femur fracture. Outcome parameters were time until surgery, complications, reoperations, mortality, and length of hospital stay.

Results

Among the proximal femur fractures (n = 358), 46.6% were pertrochanteric, 11.2% subtrochanteric, and 42.2% femoral neck fractures. Operation upon hip fractures was managed regularly within 24 hours of injury (73%; mean for femoral neck: 28.3 hrs.; mean for pertrochanteric fractures: 21.4 hrs.; mean for subtrochanteric fractures: 19.5 hrs.). Delayed treatment, as well as implantation of hip total endoprosthesis (TEP), increased the overall length of hospital stay (15.4 vs 17.6 days; 18.1 vs 15.8 days). Accordingly, surgical procedures performed within 24 hours of injury resulted in a shorter hospital residence. Longest delay of operation was measured for hip fractures (28.3 hrs.).

In 351 patients, secondary injuries were detected in 94 individuals (26%), with fractures being the most common secondary injury (n = 40). We recorded postoperative complications of nonsurgical and surgical origin, and 33.6% of our patient cohort displayed complications. Complications were distributed among 118 patients. There was no significant difference in complications regarding the time of operation, with most nonsurgical and surgical complications appearing within 24 hours after operation (n = 110 vs n = 31). Nonsurgical complications, such as anemia (n = 49) and electrolyte imbalances (n = 30), were observed more frequently than surgical complications (n = 107 vs n = 34); however, these complications were reduced by delay in surgery (82.0% in 6–24 hrs. vs 74.2% in ≥24 hrs.). Anticoagulant therapy and age did not affect postoperative complications. The hospital mortality of patients was 6.2%. Follow‐up was restrained to ambulatory visits in the clinic.

Conclusions

Surgical management of hip fractures performed within 24 hours of injury minimizes hospital stay. We did not detect significant differences in the spectrum or number of complications regarding delay of surgery. Surgical complications mainly occur with rapid primary care, and medical complications can be reduced by more intensive preparation of patient and operation procedures.

It is time for a change in the management of elderly severely injured patients! An analysis of 126,015 patients from the TraumaRegister DGU®

BACKGROUND

The number of elderly patients among the severely injured has been increasing continuously. It has been suggested that an increased life expectancy and a higher level of activity and mobility in older ages could explain this observation. Elderly trauma patients have relevant higher mortality rates and poorer functional outcomes. The reasons remain unclear. The aim of this study was to look for differences in the management of severely injured elderly patients compared to younger age groups and to evaluate their potential impact on outcome.

METHODS

The TraumaRegister DGU^® is a multicenter database that documents de-identified data of severely injured patients since 1993. Trauma cases documented between 2009 and 2016 with an ISS ≥ 9 were divided in four age groups. The groups were compared with respect to mechanism of injury, pattern of injury, severity of injury, management and outcome.

RESULTS

The analysis of 126,015 severely injured patients showed that 37.5% of the population were elderly patients (≥ 60 years). Their rate actually increased every year by 1.7%. The elderly trauma patients experience different mechanisms of injury (more low energy trauma) and different pattern of injuries (more brain trauma, less abdominal and extremity injuries). Evaluating the management of patients showed that elderly patients have lower intubation rates and less volume replacement in the prehospital setting. Diagnostic interventions like CT scans in the emergency room were performed more restrictively. Elderly trauma patients also received fewer surgical interventions for brain injuries, pelvic fractures and femur fractures. Their hospital mortality rates were higher.

CONCLUSIONS

Severely injured elderly patients are treated with a more "wait and see approach" resulting in higher mortality rates. We suggest that this population needs a more "aggressive management" to improve their outcome, if the wish to perform complete treatment including surgical procedures and intensive care medicine has not been excluded by the patients or their legal guardian.

Of Cestodes and Men: Surgical Treatment of a Spinal Hydatid Cyst

Background The cestode Echinococcus granulosus causes hydatid disease. In addition to manifestations in the liver and lung, it can lead to cystic lesions in the spine.

Case Description We report a 42-year-old male patient with primary hydatid disease in the eighth thoracic vertebra. The only clinical symptom was chronic back pain. Although laboratory findings were normal, imaging displayed lytic destruction that raised the suspicion of a metastatic disease. Diagnostics of the thoraces and abdomen did not reveal other pathologic abnormalities. Follow-up magnetic resonance imaging (MRI) depicted a progressive compression of the spinal cord and inhomogeneous structure in the fat-suppressed sequences. Because the Jamshidi biopsy was inconclusive, the tumor board recommended surgery. Dorsal decompression, spondylodesis of T6–T10, and vertebral column resection of T8 with complete cyst removal were performed. The resected vertebrae showed a mucous-like lesion with white granular tissue interfusing the whole vertebral body. A pathologic examination and enzyme-linked immunosorbent assay confirmed E. granulosus. Thus chemotherapy with albendazole was initiated. A follow-up MRI of the whole spine confirmed complete remission and found no additional resettlements. The patient's back pain was resolved without neurologic deficits.

Conclusions For lytic manifestations of the vertebral column, hydatid cysts should be considered a differential diagnosis in addition to malignant metastasis, tuberculosis, and osteomyelitis. Thorough surgical resection and strict follow-up are necessary.

Effect of alendronate or 8-prenylnaringenin applied as a single therapy or in combination with vibration on muscle structure and bone healing in ovariectomized rats

Bisphosphonate alendronate (ALN), phytoestrogen 8-prenylnaringenin (8-PN) and the whole body vibration exert a favorable effect on osteoporotic bone. However, the impact of these treatments and the combination of pharmacological therapies with biomechanical stimulation on muscle and bone has not yet been explored in detail. The effect of ALN and 8-PN and their combination with the vibration (Vib) on skeletal muscle and bone healing was investigated in ovariectomized (Ovx) rats.

Three-month old rats were Ovx (n = 78), or left intact (Non-Ovx; n = 12). Five weeks after Ovx, all rats were treated according to the group assignment (n = 12/13): 1) Non-Ovx; 2) Ovx; 3) Ovx + Vib; 4) Ovx + ALN; 5) Ovx + ALN + Vib; 6): Ovx + 8-PN; 7) Ovx + 8-PN + Vib. Treatments with ALN (0.58 mg/kg BW, in food), 8-PN (1.77 mg/kg BW, daily s.c. injections) and/or with vertical vibration (0.5 mm, 35 Hz, 1 g, 15 min, 2×/day, 5×/week) were conducted for ten weeks. Nine weeks after Ovx, all rats underwent bilateral tibia osteotomy with plate osteosynthesis and were sacrificed six weeks later.

Vibration increased fiber size and capillary density in muscle, enlarged callus area and width, and decreased callus density in tibia, and elevated alkaline phosphatase in serum. ALN and ALN + Vib enhanced capillarization and lactate dehydrogenase activity in muscle. In tibia, ALN slowed bone healing, ALN + Vib increased callus width and density, enhanced callus formation rate and expression of osteogenic genes. 8-PN and 8-PN + Vib decreased fiber size and increased capillary density in muscle; callus density and cortical width were reduced in tibia. Vibration worsened 8-PN effect on bone healing decreasing the callus width and area.

Our data suggest that Vib, ALN, 8-PN, or 8-PN + Vib do not appear to aid bone healing. ALN + Vib improved bone healing; however application is questionable since single treatments impaired bone healing. Muscle responds to the anti-osteoporosis treatments and should be included in the evaluation of the drugs.

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Vibration (Vib) was beneficial for muscle structure, it tended to interfere with early bone healing.

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Alendronate (ALN) enhanced capillary density and metabolism in muscle, slowed bone healing.

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8-Prenylnaringenin (8-PN) had favorable effects on muscle, for bone healing it was disadvantageous.

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8PN + Vib further worsened 8-PN effect on bone, ALN + Vib improved bone healing.

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Muscles respond to anti-osteoporosis treatments, their analysis should be included in the evaluation of drugs.

[Posterior vertebral column resection for correction of kyphotic deformity due to osteoporotic fractures of the thoracic spine]

OBJECTIVE

The posterior vertebral column resection (PVCR) comprises a one-step resection of the vertebral body by a costotransversectomy together with a 360° spondylodesis. After removing the vertebral body, straightening of the existing kyphotic malposition is possible.

INDICATIONS

Pronounced thoracic kyphosis after osteoporotic sintering fractures in one or more vertebral bodies.

CONTRAINDICATIONS

General contraindications for surgical procedures, ASA >3 (American Society of Anesthesiologists).

SURGICAL TECHNIQUE

First, dorsal stabilization of the vertebral column on at least two levels cranial and caudal of the VCR. Next, in a one-step procedure the laminectomy with costotransversectomy and the resection of the vertebral body is done. The ventral defect gap is filled by a mesh cage to provide ventral support. By compression the malposition is reduced and the mesh cage is fixed into position. Finally the vertebrae joints are opened up using a chisel and bone or bone substitute is placed to complete the 360° spondylodesis.

POSTOPERATIVE MANAGEMENT

Functional treatment without peak load exercises as well as appropriate osteoporosis treatment.

RESULTS

In a retrospective study 10 patients treated with this surgical technique were investigated. The results show a very good correction of the kyphotic maldeformity while the complications remain moderate.

[Dorsal stabilization of C1/C2 modified according to Goel-Harms with C1 pedicle screws]

OBJECTIVE

Stabilization of the atlantoaxial transition by an alternative screw position in C1.

INDICATIONS

Instabilities C1/C2 due to inflammation, tumor or trauma.

CONTRAINDICATIONS

Presence of a very small pedicle of C1. Variations in the course of the vertebral arteries.

SURGICAL TECHNIQUE

The midline approach to the upper cervical spine is used for the modified instrumentation of C1 with pedicle screws instead of Harms screws and for the unaltered instrumentation of C2. Depending on the indication, dorsal spondylodesis is performed by opening the laminae and attaching ceramic bone substitute material.

POSTOPERATIVE MANAGEMENT

In mobile patients, additional immobilisation with a soft collar is recommended for 6 weeks. Full recovery is given 3-4 months after surgery.

RESULTS

From January 2017 to September 2018, 21 stabilizations of the atlantoaxial transition were performed. The mean age was 72.52 ± 15.45 years. A total of 42 screws were placed in C1. In all, 21 (50%) C1 pedicle screwscould be placed, and in other 21 cases Harms screws were used. Complications were seen in 3 patients. Overall, considering the contraindications, the instrumentation of C1 with pedicle screws appears as a safe alternative to instrumentation with Harms screws.

[Intraoperative revision of initially loosened pedicle screws]

OBJECTIVE

Intraoperative revision of initially loosened pedicle screws.

INDICATIONS

Intraoperatively loosened/stripped pedicle screws.

CONTRAINDICATIONS

None.

SURGICAL TECHNIQUE

Removal of the loosened/stripped pedicle screw. Checking the screw channel and re-implantation using a different trajectory, a larger screw diameter or a cement-augmented pedicle screw.

POSTOPERATIVE MANAGEMENT

Early functional mobilization and initiation of osteoporosis therapy if indicated.

RESULTS

A biomechanical study with human vertebral bodies was performed. Augmented and not augmented pedicle screws were tested until loosening using a fatigue testing setup. After loosening occurred a subsequent augmentation of the loosened, not augmented screw was performed, and it was tested using a fatigue test again. Both the initial (p = 0.009) and the augmentation after loosening (p = 0.001) showed a significant increase in failure load compared to the non-augmented pedicle screws. In our own patient collective from April 2016 to August 2018, 11 of 524 patients treated with pedicle screws showed intraoperative screw loosening. This was revised in 6 cases with a subsequent augmentation and in 5 cases with a larger screw diameter. In the postoperative control at 6 weeks, none of these screws showed loosening again.

[Pedicle subtraction osteotomy to correct rigid deformities]

OBJECTIVE

The aim of the surgery is to restore the sagittal profile in the event of a mismatch of the patient's spinopelvic parameters and high patient suffering.

INDICATIONS

Clinically symptomatic sagittal imbalance due to degeneration, trauma or after spinal surgery which can not be adequately treated by conservative therapy.

CONTRAINDICATIONS

Severe general disease of the patient; local or systemic inflammation.

SURGICAL TECHNIQUE

A dorsal approach is used to resect the dorsal vertebral structures and to perform an osteotomy to the anterior edge of the spine.

POSTOPERATIVE MANAGEMENT

Rest with a load limit of 5 kg for 3 months. Prohibition of deep sitting for this time.

RESULTS

The pedicle subtraction osteotomy is described in the literature as a reliable method for the treatment of sagittal imbalance. The high rate of described complications should be discussed preoperatively with the patient.

Evaluation of ostarine as a selective androgen receptor modulator in a rat model of postmenopausal osteoporosis

Selective androgen receptor modulators (SARMs) have shown beneficial effects on muscle wasting, general physical function and bone properties in male mammals. However, data on the effects of SARMs in postmenopausal osteoporotic bone are scarce. We evaluated the effects of the SARM drug ostarine on postmenopausal osteoporotic bone in a rat osteoporosis model. Ovariectomy was performed on 46 of 56 3-month-old female Sprague-Dawley rats. Eight weeks after ovariectomy, ostarine was orally administered daily for 5 weeks in dosages of 0.04 (low, OVX + Ost. 0.04), 0.4 (intermediate, OVX + Ost. 0.4), and 4 mg/kg (high, OVX + Ost. 4) body weight. Another ovariectomized group received no ostarine. Lumbar vertebrae and femora were removed for biomechanical, gene expression, ashing, and computer tomography analyses. Low dose showed no effects. The effects of intermediate and high doses were comparable overall. Improvements were mainly seen in structural properties such as bone mineral density and bone volume density. However, the effects in femora were superior to effects in vertebrae. Ostarine treatment for 5 weeks did not improve significantly biomechanical properties. mRNA expression of the receptor activator of NF-κB ligand decreased after treatment, and uterine weight increased. Serum levels of phosphorus increased following ostarine treatment in intermediate and high-dose groups. Short-term treatment of osteoporotic bone with ostarine leads to improvement of several microstructural bone indices. While we did not observe changes in biomechanics, it is conceivable that longer treatment may also improve biomechanical properties. Further studies are needed to characterize longer time effects and side effects of ostarine in osteoporosis.

Effect of the lipoxygenase inhibitor baicalein on bone tissue and bone healing in ovariectomized rats

BACKGROUND

Osteoporosis is one of the world's major medical burdens in the twenty-first century. Pharmaceutical intervention currently focusses on decelerating bone loss, but phytochemicals such as baicalein, which is a lipoxygenase inhibitor, may rescue bone loss. Studies evaluating the effect of baicalein in vivo are rare.

METHODS

We administered baicalein to sixty-one three-month-old female Sprague-Dawley rats. They were divided into five groups, four of which were ovariectomized (OVX) and one non-ovariectomized (NON-OVX). Eight weeks after ovariectomy, bilateral tibial osteotomy with plate osteosynthesis was performed and bone formation quantified. Baicalein was administered subcutaneously using three doses (C1: 1 mg/kg BW; C2: 10 mg/kg BW; and C3: 100 mg/kg BW) eight weeks after ovariectomy for four weeks. Finally, femora and tibiae were collected. Biomechanical tests, micro-CT, ashing, histological and gene expression analyses were performed.

RESULTS

Biomechanical properties were unchanged in tibiae and reduced in femora. In tibiae, C1 treatment enhanced callus density and cortical width and decreased callus area. In the C3 group, callus formation was reduced during the first 3 weeks after osteotomy, correlating to a higher mRNA expression of Osteocalcin, Tartrate-resistant acid phosphatase and Rankl. In femora, baicalein treatments did not alter bone parameters.

CONCLUSIONS

Baicalein enhanced callus density and cortical width but impaired early callus formation in tibiae. In femora, it diminished the biomechanical properties and calcium-to-phosphate ratio. Thus, it is not advisable to apply baicalein to treat early bone fractures. To determine the exact effects on bone healing, further studies in which baicalein treatments are started at different stages of healing are needed.

Changes in Musculoskeletal System and Metabolism in Osteoporotic Rats Treated With Urocortin

Objective: In aging population, postmenopausal osteoporosis and decline of musculoskeletal function, referred to as "frailty syndrome" lead to loss of bone and muscle, causing falls, and fall-related injuries. To limit the impact of this portentous duo, simultaneous treatment of both is needed. Urocortin (UCN) has been reported to improve osteoporotic bone properties while its effect on muscle has not been addressed yet. Design and Methods: We aimed to investigate the effect of urocortin in vivo on skeletal muscle structure in osteopenic rats. Sixty Sprague-Dawley rats were divided into five groups: four were ovariectomized (OVX) and one underwent sham operation (SHAM). One ovariectomized group was left untreated (OVX), while one was treated with urocortin s.c. in 3 μg/kg body weight (bw) (OVX+UCN low), one with 30 μg/kg (OVX+UCN high), while one group was treated with estradiol orally (OVX+E: 0.2 mg/kg bw), each for 35 days. Mm. gastrocnemius, longissimus, and soleus were isolated and capillary density as well as diameters of type I and II fibers were measured. In addition, we examined the effect of UCN on tibia using biomechanical, micro-CT and ashing analysis and investigated the blood serum. Results: We demonstrated a positive effect of UCN on M. soleus, in which fiber diameter was positively influenced. The biomechanical and structural parameters of bone were not changed in UCN treated rats. The higher cholesterol, glucose and triglyceride levels in the "UCN high" group raise concern about this treatment. Conclusions: Our results portray urocortin as a substance that can be assessed for future therapeutic treatments of estrogen deficiency. New and Noteworthy: Urocortin has a positive effect on M. soleus (diameter). Urocortin raises serum cholesterol and triglyceride levels. Bone tissue was not affected by UCN.

Biomechanical and histological analyses of the fracture healing process after direct or prolonged reduction

Background

Reduction of femoral shaft fractures remains a challenging problem in orthopaedic surgery. Robot-assisted reduction might ease reduction and fracture treatment. However, the influence of different reduction pathways on patients’ physiology is not fully known yet. Therefore, the aim of this study was to examine the biomechanics and histology of fracture healing after direct and prolonged robot-assisted reduction in an in vivo rat model.

Methods

144 male CD^® rats were randomly assigned to 12 groups. Each animal received an external fixator and an osteotomy on the left femoral shaft. On the fourth postoperative day, the 1× reduction groups received a single reduction maneuver, whereas the 10× reduction groups received the same reduction pathway with ten repetitions. The control groups did not undergo any reduction maneuvers. Animals were killed after 1, 2, 3 and 4 weeks, respectively, and the composition of the fracture gap was analyzed by µCT and non-decalcified histology. Biomechanical properties were investigated by a three-point bending test, and the bone turnover markers PINP, bCTx, OPG, sRANKL, TRACP-5b, BALP, and OT/BGP were measured.

Results

One week after the reduction maneuver, µCT analysis showed a higher cortical bone volume in the 1× reduction group compared to the 10× reduction group. Biomechanically, the control group showed higher maximum force values measured by three-point bending test compared to both reduction groups. Furthermore, less collagen I formation was examined in the 10× reduction group compared to the control group after 1 week of fracture healing. PINP concentration was decreased in 10× reduction group after 1 week compared to control group. The same trend was seen after 3 weeks.

Conclusion

A single reduction maneuver has a beneficial effect in the early phase of the fracture healing process compared to repeated reduction maneuvers. In the later phase of fracture healing, no differences were found between the groups.

Effects of RANKL Knockdown by Virus-like Particle-Mediated RNAi in a Rat Model of Osteoporosis

Rebalancing of the RANKL/OPG system seems to be an effective treatment strategy in postmenopausal osteoporosis. Here, we evaluate the knockdown of RANKL by in-vivo-delivered siRNA in a rat model of osteoporosis. Virus-like-particles (VLPs) derived from polyoma JC virus were used for delivering RANKL siRNA in ovariectomized (OVX) rats. 48 rats were ovariectomized and treated with either 17β-estradiol (E2), VLPs containing RANKL siRNA (siRANKL), or VLPs containing non-cognate siRNA (siCtrl). All OVX groups were subdivided into the prophylaxis group (PG) and the therapy group (TG). The PG received treatment directly after being OVX for 10 weeks. The TG received treatment 5 weeks after being OVX for 5 weeks. Rats were sacrificed 10 weeks after being OVX. Bone and blood samples were analyzed. E2 and siRANKL showed a significant knockdown of RANKL mRNA. A protein knockdown was observed with E2 and siRANKL in the TG but not in the PG. No distinct improvements in biomechanical and morphological properties of the bones were observed after siRANKL treatment. In the PG, E2 protected the bone structure. We demonstrated successful mRNA and protein knockdown by VLP-mediated RNAi in vivo. Knockdown of membranous RANKL did not result in significant improvements of bone properties in this model of early-stage postmenopausal osteoporosis.

The Advantages of Bilateral Osteotomy Over Unilateral Osteotomy for Osteoporotic Bone Healing

Most models of osteoporotic bone fractures are performed unilaterally (UL). We investigated healing of tibia osteotomy performed either UL or bilaterally (BL) in ovariectomized rats. Behavior of animals and muscle structure were assessed. Three-month-old female Sprague-Dawley rats were ovariectomized (n = 32). After 10 weeks, half the rats underwent UL osteotomy of tibia metaphysis (right limb) with plate osteosynthesis. The other rats were osteotomized BL. Half of the rats in each group received either standard pain treatment with carprofen (5 mg/kg body weight (BW), 1x/day for 2 days) or carprofen and buprenorphine (5 mg/kg BW, 1x/day and 0.03 mg/kg BW, 2x/day for 5 days) after osteotomy. The UL rats started to load the injured limb from day 27 ± 9; BL rats did this from day 4 ± 4 onward. The UL rats more frequently loaded only one hind limb; BL rats more often loaded both hind limbs. Osteotomy was not bridged in 20% of UL rats and in 4% of BL rats. Callus volume and bone volume fraction were lower in UL group. Weight and fiber size of UL-intact limb muscles were enhanced, compared to the osteotomized limb and those in BL group. Most of the other parameters which assess physiology, activity, body posture, head, or coat were not different. The effect of two pain therapies was not significant on any variable studied. Welfare of the animals was acceptable in all rats. In UL rats, bone healing was delayed. The more advanced healing in BL rats suggested a positive effect of earlier loading. In studies on bone healing, it is advisable to perform BL osteotomy.

Effect of Strontium Ranelate on the Muscle and Vertebrae of Ovariectomized Rats

Osteoporosis is often accompanied by sarcopenia. The effect of strontium ranelate (SR) on muscle tissue has not been investigated sufficiently. In this study, the effect of different SR treatments on muscle was studied. Additionally, the lumbar vertebrae were analyzed. Three-month-old female rats were divided into five groups (n = 12): Group 1: untreated (NON-OVX); Group 2: ovariectomized and left untreated (OVX); Group 3: SR after OVX until the study ended (13 weeks, SR prophylaxis and therapy = pr+th); Group 4: OVX and SR for 8 weeks (SR prophylaxis = pr); Group 5: SR for 5 weeks from the 8 week after OVX (SR therapy = SR th). SR was applied in food (630 mg/kg body weight). The size of muscle fibers, capillary density, metabolic enzymes, and mRNA expression were assessed in soleus, gastrocnemius, and longissimus muscles. The vertebral bodies underwent micro-CT, biomechanical, and ashing analyses. In general, SR did not alter the muscle histological parameters. The changes in fiber size and capillary ratio were related to the body weight. Myostatin mRNA was decreased in Sr pr+th; protein expression was not changed. SR th led to increase in mRNA expression of vascular endothelial growth factor (Vegf-B). In lumbar spine, SR pr+th enhanced biomechanical properties, bone mineral density, trabecular area, density, and thickness and cortical density. The reduced calcium/phosphate ratio in the SR pr+th group indicates the replacement of calcium by strontium ions. SR has no adverse effects on muscle tissue and it shows a favorable time-dependent effect on vertebrae. A functional analysis of muscles could verify these findings.

[Promoting Young Talents in Trauma Surgery through Students-On-Call]

BACKGROUND

Due to restrictions on admission to medical school, changing claims to an optimized work-life balance and occupational perspectives, surgical professions in particular are struggling with strategies to motivate young academics. Surgical disziplines aim towards a profound transfer of knowledge and pique student's interest by ensuring a sustainable education at university.

OBJECTIVES

The goal of this study was to evaluate a Students-On-Call System (SOCS) and to identify a financial benefit.

MATERIALS AND METHODS

In this study the SOCS was compared pre-/postevaluation using questionnaires and the supporting X‑rays within a curricular teaching module of orthopedic trauma surgery, with students in the fourth semester of specialism and those in the practical semester at medical school.

RESULTS

The students of SOCS showed significantly better results prior to the course and afterwards than the two other groups. By establishing SOCS medical students get involved into the treatment of emergency patients in the trauma resuscitation unit (TRU) and operating room (OR). Students get the chance to enhance their comprehension of diagnostics, therapy and decision making in surgical context. This highly valuable traineeship combines a minimized teaching effort with an effective motivation of young academcis for the surgical profession. A SOCS has reduced the workload of medical colleagues. Establishing SOCS spare the residents being on call and results in reduced costs of 23,659.86 Euro per year.

CONCLUSION

The results presented show that the SOCS leads to an excellent cost-benefit balance, which has been established in multiple surgical departments at the medical school of the University of Göttingen. Apart from practice-oriented surgical teaching, the SOCS is a way of promoting successful young talent saving resources in the medical on-call services.