Comparison of anatomic axes with a navigated functional rotation axis determined by ligament tension for rotational femoral component alignment in cadaver knee arthroplasty.

INTRODUCION: The malimplantation of the total knee arthroplasty (TKA) components is one of the main reasons for revision surgery. For determining the correct intraoperative femoral rotation several anatomic rotational axes were described in order to achieve a parallel, balanced flexion gap. In this cadaveric study prevalent used rotational femoral axes and a navigated functional rotational axis were compared to the flexion-extension axis defined as the gold standard in rotation for femoral TKA component rotation. MATERIALS AND METHODS: Thirteen body donors with knee osteoarthritis (mean age: 78.85 ± 6.09; eight females and five males) were examined. Rotational computer tomography was performed on their lower extremities pre- and postoperatively. Knee joint arthroplasties were implanted and CT diagnostics were used to compare the preoperatively determined flexion-extension axis (FEA). The FEA is the axis determined by our surgical technique and serves as an internal reference. It was compared to other axes such as (i) the anatomical transepicondylar axis (aTEA), (ii) the surgical transepicondylar axis (sTEA), (iii) the posterior condylar axis (PCA) and (iv) the functional rotation axis (fRA). RESULTS: Examination of 26 knee joint arthroplasties revealed a significant angular deviation (p*** < 0.0001) for all axes when the individual axes and FEA were compared. aTEA show mean angular deviation of 5.2° (± 4.5), sTEA was 2.7° (± 2.2), PCA 2.9° (± 2.3) and the deviation of fRA was 4.3° (± 2.7). A tendency towards external rotation was observed for the relative and maximum axis deviations of the aTEA to the FEA, for the sTEA and the fRA. However, the rotation of the posterior condylar axis was towards inwards. CONCLUSIONS: All axes showed a significant angular deviation from the FEA. We conclude that the presented technique achieves comparable results in terms of FEA reconstruction when compared with the use of the known surrogate axes, with certain deviations in terms of outliers in the internal or external rotation.

Clinical outcome after dorso-ventral stabilization of the thoracolumbar and lumbar spine with vertebral body replacement and dorsal stabilization.

PURPOSE: Surgical stabilization of the spine by vertebral body replacement (VBR) is used for spinal disorders such as traumatic fractures to provide an anatomical re-adjustment of the spine to prevent late detrimental effects and pain [1-4]. This study addresses the clinical outcome after a ventral intervention with VBR and bisegmental fusion. METHODS: The study includes 76 patients (mean age: 59.34 ± 15.97; 34 females and 42 males) with fractures in the lower thoracic and lumbar spine. They were selected from patients of our hospital who received an anterolateral VBR surgery on the corresponding lower spine region over a nine-year period. Only patients were examined with X-rays and complete follow-up records. Exclusion criteria were changes due to degeneration and pathological fractures. Patients were divided into two groups, the thoracotomy group (Th10-L1) and the lumbotomy group (L2-5), respectively. Minimum one year after surgery, patients were asked about their well-being using a precasted questionnaire. RESULTS: No significant differences with respect to the subjective impression of the patients concerning their back pain, spinal functional impairment, their general functional status and their quality of life impairment. Unfortunately, however, only a rather modest but significant increase of the post-surgical life quality was reported. CONCLUSIONS: Patients who underwent VBR in the lower thoracic or lumbar spine show modest long-term well-being. The results suggest that injuries to the lower thoracic or lumbar spine requiring vertebral body replacement should be classified as severe injuries since they adversely affect the patients' long-term well-being. TRIAL REGISTRATION: Study of clinical outcome of patients after vertebral body replacement of the ventral thoracal and lumbal spine, DRKS00031452. Registered 10th March 2023 - Prospectively registered. Trial registration number DRKS00031452.

[Treatment strategy for an unstable chest wall after cardiopulmonary resuscitation]. / Versorgungsstrategie des instabilen Thorax nach kardiopulmonaler Reanimation.

Every year ca. 60,000 people in Germany undergo cardiopulmonary resuscitation (CPR). The two most frequent underlying causes are of cardiopulmonary and traumatic origin. According to the current CPR guidelines chest compressions should be performed in the middle of the sternum with a pressure frequency of 100-120/min and to a depth of 5-6 cm. In contrast to trauma patients where different injury patterns can arise depending on the accident mechanism, both the type of trauma and the injury pattern are similar in patients after CPR due to repetitive thorax compression. It is known that an early reconstruction of the thoracic wall and the restoration of the physiological breathing mechanics in trauma patients with unstable thoracic injuries reduce the rates of pneumonia and weaning failure and shorten the length of stay in the intensive care unit. As a result, it is increasingly being propagated that an unstable thoracic injury as a result of CPR should also be subjected to surgical treatment as soon as possible. In the hospital of the authors an algorithm was formulated based on clinical experience and the underlying evidence in a traumatological context and a surgical treatment strategy was designed, which is presented and discussed taking the available evidence into account.

Evaluation of the interhospital patient transfer after implementation of a regionalized trauma care system (TraumaNetzwerk DGU®) in Germany.

Purpose: The aim of the study was to evaluate how many patients are being transferred between trauma centers and and their characteristics in the 2006 initiated TraumaNetzwerk DGU® (TNW). We further investigated the time point of transfer and differences in outcome, compared to patients not being transferred. We wanted to know how trauma centers judged the performance of the TNW in transfer. Method: (1) We analyzed the data of the TraumaRegister DGU® (TR-DGU) from 2014-2018. Included were patients that were treated in German trauma centers, maximum AIS (MAIS) >2 and MAIS 2 only in case of admission on ICU or death of the patient. Patients being transferred were compared to patients who were not. Characteristics were compared, and a logistic regression analysis performed to identify predictive factors. (2) We performed a survey in the TNW focussing on frequency, timing and communication between hospitals and improvement through TNW. Results: Study I analyzed 143,195 patients from the TR-DGU. Their mean ISS was 17.8 points (SD 11.5). 56.4% were admitted primarily to a Level-I, 32.2% to a Level-II and 11.4% to a Level-III Trauma Center. 10,450 patients (7.9%) were transferred. 3,667 patients (22.7%) of the admitted patients of Level-III Center and 5,610 (12.6%) of Level-II Center were transferred, these patients showed a higher ISS (Level-III: 18.1 vs. 12.9; Level-II: 20.1 vs. 15.8) with more often a severe brain injury (AIS 3+) (Level-III: 43.6% vs. 13.1%; Level-II: 53.2% vs. 23.8%). Regression analysis showed ISS 25+ and severe brain injury AIS 3+ are predictive factors for patients needing a rapid transfer. Study II: 215 complete questionnaires (34%) of the 632 trauma centers. Transfers were executed within 2 h after the accident (Level-III: 55.3%; Level-II: 25.0%) and between 2-6 h (Level-III: 39.5%; Level-II: 51.3%). Most trauma centers judged that implementation of TNW improved trauma care significantly (Level III: 65.0%; Level-II: 61.4%, Level-I: 56.7%). Conclusion: The implementation of TNW has improved the communication and quality of comprehensive trauma care of severely injured patients within Germany. Transfer is mostly organized efficient. Predictors such as higher level of head injury reveal that preclinical algorithm present a potential of further improvement.

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.

Changes of the subchondral bone microchannel network in early osteoarthritis.

OBJECTIVE: We have identified a 3D network of subchondral microchannels that connects the deep zone of cartilage to the bone marrow (i.e., cartilage-bone marrow microchannel connectors; CMMC). However, the pathological significance of CMMC is largely unknown. Here, we quantitatively evaluated how the CMMC microarchitecture is related to cartilage condition, as well as regional differences in early idiopathic osteoarthritis (OA). METHODS: Two groups of cadaveric female human femoral heads (intact cartilage vs early cartilage lesions) were identified, and a biopsy-based high-resolution micro-CT imaging was employed. Subchondral bone (SB) thickness, CMMC number, maximum and minimum CMMC size, and the CMMC morphology were quantified and compared between the two groups. The effect of joint's region and cartilage condition was examined on each dependent variable. RESULTS: The CMMC number and morphology were affected by region of the joint, but not by cartilage condition. On the other hand, the minimum and maximum CMMC size was changed by both the location on the joint, as well as the cartilage condition. The smallest CMMC were consistently detected at the load-bearing region (LBR) of the joint. Compared to non-pathological subjects, the size of the microchannels was enlarged in early OA, most noticeably at the non-load-bearing region (NLBR) and the peripheral rim (PR) of the femoral head. Furthermore, subchondral bone thinning was observed in early OA as a localized occurrence linked with areas of partial chondral defect. CONCLUSION: Our data point to an enlargement of the SB microchannel network, and a collective structural deterioration of SB in early idiopathic OA.

Do patients need advice and information to prevent infections - results of a single centre structured survey.

Background: Healthcare-associated infections are a major burden for hospitals, leading to morbidity and mortality and unnecessary medical costs. They can probably be reduced through what is known as patient empowerment. This study aims to address the question of whether patients are interested in receiving infection prevention and control information. Methods: Patients were asked in structured interviews whether they would like more information on infection prevention and control. Inclusion criteria comprised 2 groups of patients. Group 1 were patients undergoing elective total endoprosthesis (TEP) and Group 2 were patients tested positive for meticillin-resistant Staphylococcus aureus (MRSA). Results: The response rate was 38.4 % (163/425 patients). Approximately 75 % of the patients were interested in information on infection prevention and control. The topics of interest differed between the two patient groups: MRSA patients had a higher need for infection prevention and control information. TEP patients showed a high acceptance of antiseptic body wash and a willingness to pay for it themselves. Information given to patients should be group-specific and timely. Conclusion: Our data suggest a lack of information on infection prevention and control among patients and underline the importance of patient empowerment. The willingness of patients to pay personally for antiseptic wash should be assessed further.

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.

[Complication rate after femoral shaft fractures in childhood and adolescence depending on patient factors and treatment measures]. / Die Komplikationsrate nach Femurschaftfrakturen im Kindes- und Jugendalter in Abhängigkeit von Patientenfaktoren und Behandlungsmaßnahmen.

BACKGROUND: The treatment of pediatric femoral shaft fractures has undergone an increasing change in recent years. The previously predominant treatment procedures were extensively replaced by minimally invasive techniques (e.g. elastic stable intramedullary nailing, ESIN). The aim of this study was the comparison of complication rates depending on patient factors as well as various treatment procedures. MATERIAL AND METHODS: This study involved a retrospective X­ray morphometric evaluation of data. The patient files and X­rays of 101 children who were treated at 2 level I trauma centers were analyzed. RESULTS: Conservative treatment was carried out in 19% of the cases. Among the surgical procedures the ESIN technique was predominant (n = 60). Complications that needed revision occurred in 10% of the children after conservative treatment. Revision surgery had to be carried out in more than 6% of the cases in children who were surgically treated. Among the surgical procedures ESIN stabilization demonstrated the lowest revision rate with only 3%. Children under three years and adolescents had a higher risk for developing complications. If the ESIN wires used were too thin in relation to the diameter of the medullary cavity there was an increased probability of complications of around 30%. CONCLUSION: This study revealed a moderate risk of complications in the treatment of femoral shaft fractures in children. The risk of complications after external fixation and conservative treatment was the highest in this study. Overall, the ESIN technique showed the lowest risk of complications. The results of this study could confirm the known limitations of the ESIN technique depending on age and body weight.

Predicting the disaster - The role of CRP in acetabular surgery.

OBJECTIVES: Acetabular fractures represent a complex surgical challenge. Given the heterogenous fracture pattern, the patient characteristics and spectrum of complications demand individual solutions. Surgical site infections (SSI) threaten osteosynthesis, and early detection of them and treatment remain crucial. What is the value of postoperative C-reactive protein (CRP) in this group of patients as well as its normal course? DESIGN & METHODS: 115 patients with isolated fractures of the acetabulum were retrospectively evaluated. CRP, white blood cell count (WBC) and fracture patterns as well as patient characteristics were assessed for 20 days following operative fixation of the acetabular fracture (n = 71) and in fractures that were managed conservatively (n = 44). RESULTS: Twelve patients suffered an infectious complication. With a one-phase decay, 70.55% of the variance of postoperative CRP kinetics was predicted. To anticipate maximum CRP as well as an infection, the preoperative CRP represented the best prognostic parameter. To predict an infection, the single variable "peak CRP value above 100 mg/l" resulted in a sensitivity and specificity of 91.67% and 36.21%, respectively. Combining a second peak of CRP with maximum CRP and day 5 CRP value for receiver-operating characteristic (ROC) analysis resulted in 83.3% and 88.1%, respectively. CONCLUSIONS: Predicting surgical site infections after an acetabular fracture is most predictive when analyzing the maximum overall CRP, the second peak and the CRP after day 5. With a combination of these parameters, a sensitivity and specificity of 83.3% and 88.1% to detect an infection was achieved.

C-reactive protein in spinal surgery: more predictive than prehistoric.

PURPOSE: In spinal surgery, surgical site infections (SSI) after dorsal spondylodesis lead to severe short- and long-term complications. Despite various clinical and serological evidence, the detection of a postoperative SSI remains crucial. In this retrospective cohort study, we determined the prognostic value of C-reactive protein (CRP) kinetics after open reduction and dorsal spondylodesis in the development of a SSI. METHODS: We retrospectively analyzed 192 patients from 2016 to 2018 undergoing open reduction and dorsal spondylodesis with and without SSI for 20 days at a level-I trauma center and assessed their serological and clinical characteristics. RESULTS: On day 7 and 8 after surgery, patients who developed a SSI displayed significantly higher CRP levels. A second peak after the initial maximum of CRP and a restricted failure to decline as well as a maximum CRP of more than 225 mg/l predict an infectious complication with a sensitivity of 92.9%, and a specificity of 78.2%. A binary logistic regression leads to 85.7% and 69.7%, respectively. A one-phase decay exponential regression can predict 75.6% of the variance after the initial peak of CRP. CONCLUSION: Our study demonstrates a high value of postoperative CRP kinetics in SSI detection after dorsal spondylodesis. Moreover, we observed typical CRP levels with a specific course as indicative predictors that may facilitate an early SSI detection in clinical practice.

Analysis of low-dose estrogen on callus BMD as measured by pQCT in postmenopausal women.

BACKGROUND: Osteoporosis affects elderly patients of both sexes. It is characterized by an increased fracture risk due to defective remodeling of the bone microarchitecture. It affects in particular postmenopausal women due to their decreased levels of estrogen. Preclinical studies with animals demonstrated that loss of estrogen had a negative effect on bone healing and that increasing the estrogen level led to a better bone healing. We asked whether increasing the estrogen level in menopausal patients has a beneficial effect on bone mineral density (BMD) during callus formation after a bone fracture. METHODS: To investigate whether estrogen has a beneficial effect on callus BMD of postmenopausal patients, we performed a prospective double-blinded randomized study with 76 patients suffering from distal radius fractures. A total of 31 patients (71.13 years ±11.99) were treated with estrogen and 45 patients (75.62 years ±10.47) served as untreated controls. Calculated bone density as well as cortical bone density were determined by peripheral quantitative computed tomography (pQCT) prior to and 6 weeks after the surgery. Comparative measurements were performed at the fractured site and at the corresponding position of the non-fractured arm. RESULTS: We found that unlike with preclinical models, bone fracture healing of human patients was not improved in response to estrogen treatment. Furthermore, we observed no dependence between age-dependent bone tissue loss and constant callus formation in the patients. CONCLUSIONS: Transdermally applied estrogen to postmenopausal women, which results in estrogen levels similar to the systemic level of premenopausal women, has no significant beneficial effect on callus BMD as measured by pQCT, as recently shown in preclinical animal models. TRIAL REGISTRATION: Low dose estrogen has no significant effect on bone fracture healing measured by pQCT in postmenopausal women, DRKS00019858 . Registered 25th November 2019 - Retrospectively registered. Trial registration number DRKS00019858 .

[Periprosthetic fractures around the knee]. / Periprothetische Frakturen rund um das Knie.

BACKGROUND: Periprosthetic fractures of the knee joint are complex injuries and frequently represent a challenge for the surgeon. OBJECTIVE: The aim of this review is to present and discuss the current classification and treatment options for periprosthetic knee fractures. MATERIAL AND METHODS: A selective review of the existing literature on periprosthetic fractures around the knee was performed in PubMed. The various classifications and treatment regimens are discussed with respect to the advantages and disadvantages and from this knowledge a new algorithm was developed. RESULTS: The classifications of periprosthetic fractures have changed in recent years and have been replaced by a uniform fracture classification; however, not only the radiological evaluation of the fractures is crucial to determine the treatment regimen for periprosthetic fractures. A thorough evaluation of the inserted endoprosthesis should be carried out in order to be able to decide between the treatment options of osteosynthesis and revision arthroplasty. Treatment options are available for osteosynthesis and revision arthroplasty that enable a safe treatment of these complex injuries. CONCLUSION: Periprosthetic fractures of the knee joint are complex injuries, requiring a thorough preoperative planning and an interdisciplinary treatment with trauma and endoprosthetic expertise.

[Refixation of osteochondral fragments with resorbable polylactid implants : Long-term clincal and MRI results]. / Refixation von osteochondralen Fragmenten mit resorbierbaren Polylactid-Implantaten : Klinische und MR-morphologische Langzeitergebnisse.

BACKGROUND: Refixation with resorbable implants is a common surgical treatment in patients who suffer an injury with shearing of an osteochondral flake due to trauma of the knee or the upper ankle joint. To date there are no studies which outline long-term outcomes for this procedure. The aim of this study was to evaluate long-term clinical and magnetic resonance imaging (MRI) results after refixation with resorbable polylactide (PLLA) implants. MATERIAL AND METHODS: In this retrospective study 12 patients with 13 injuries were examined 13.9 years (±1.2 years) after refixation of an osteochondral fragment of the knee (10 patients) and the upper ankle joint (2 patients) with a mean size of 3.33 cm2 (±2.33) by resorbable polylactide (PLLA) implants (nails, pins, screws, Bionx, Tampere, Finland). To objectify the clinical results eight established clinical scores (VASS, Tegner, Lysholm, McDermott, KSS, WOMAC, AOFAS, FADI+Sports) were used. Furthermore, the morphological integration of bone and cartilage was assessed by MRI (3 T) using proton-weighted and cartilage-sensitive 3D double-echo steady-state (DESS) sequences. The morphological results were objectified with a modified MRI score according to Henderson et al. RESULTS: After 13.9 years (±1.2) the patients with an injury of the knee as well as of the upper ankle joint showed good to excellent results (knee: VASS 1.2 (±1.7), Tegner 4.4 (±1.3), Lysholm 85.7 (±12.2), McDermott 90.7 (±8.6), KSS 189 (±14.2), WOMAC (6.16% (±8.45)) (upper ankle joint: VASS 2.5 (±2.5), Tegner 5.5 (±1.5), Lysholm 87 (±13), McDermott 88 (±12); WOMAC (8.54% (±8.54), AOFAS 75.5 (±24.5), FADI+Sports 118 (±18)). In all cases there was evidence of good integration of the osteochondral fragment in MRI. In five patients there was moderate subchondral cyst formation (∅ ≤1 mm); however, mild changes of the cartilage contour were found in all patients. The mean modified Henderson score achieved was 14.4 (±2.0, best 8, worst 32), which corresponds to a good morphological result. CONCLUSION: Because of good clinical and morphological results shown by MRI, refixation through resorbable implants (PLLA) can be recommended for treatment of traumatic osteochondral flakes.

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.

[Posterior vertebral column resection for correction of kyphotic deformity due to osteoporotic fractures of the thoracic spine]. / Posterior vertebral column resection (PVCR) zur Korrektur von Hyperkyphosen bei osteoporotischen Frakturen der Brustwirbelsäule.

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.

[Pedicle subtraction osteotomy to correct rigid deformities]. / Pedikelsubtraktionsosteotomie zur Korrektur rigider Deformitäten.

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.

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.