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 .

Advanced Unilateral Fibrous Dysplasia of the Scapula: A Rare Clinical Entity and Surgical Challenge.

INTRODUCTION: Fibrous dysplasia (FD) is an uncommon benign tumor of bone. Although FD can affect flat bones, it is rare for the scapula to be involved. In addition, little is known about the management of FD when it involves the scapula. We present possibly the first comprehensive case report of the management of advanced unilateral FD of the scapular region. CASE REPORT: A 47-year-old male presented to us with pain and swelling over the left shoulder. The swelling was 11 cm × 15 cm × 8 cm and was hard and tender with rough texture. Radiograph showed large homogenous lesion with irregular but well-defined margins and a ground glass appearance. Magnetic resonance imaging scans showed well-defined borders with the expansion of the bone, with intact overlying cortices and endosteal scalloping. Biopsy confirmed the lesion to be FD. An innovative application of an existing surgical technique to minimize the impact of the residual deformity and dead space left after curettage of the scapula was done. The patient had good clinical and functional outcome at 6-month follow-up. CONCLUSION: Surgical exercise in FD is purely on symptomatic basis. In our case, the swelling was causing most discomfort, and we curettaged and compressed the bony swelling which resulted in excellent outcome in this patient.

Incidence and severity of malreduction of the tibiofibular syndesmosis following surgical treatement of displaced ankle fractures and impact on the function -Clinical study and MRI evaluation.

PURPOSE: To compare tibiofibular reduction quality in different types of operatively treated ankle fractures and the impact on clinical and functional outcome at mid-term follow-up. PATIENTS AND METHODS: One hundred patients with an acute ankle fracture who had undergone open reduction and internal fixation were included. Eighty-eight patients who suffered from ligamentous ankle injury with neither fracture nor syndesmotic lesions served as a control group. Tibiofibular alignment was measured on MR images in all 188 patients. In case of tibiofibular malreduction tibiotalar positioning was determined as well. Clinical and functional outcome was assessed using the AOFAS hindfoot score as well as the SF-36. RESULTS: No tibiofibular malreduction was found in type Weber B fractures, irrespective of syndesmotic instability followed by syndesmotic screw placement, as compared to the control group. A significant tibiofibular malreduction was detected in bimalleolar/trimalleolar/dislocated type Weber B fractures and in isolated type Weber C fractures with syndesmotic screw, in comparison to the control group. Tibiotalar displacement could not be detected. Clinical and functional outcome analysis revealed no significant differences between the treatment groups. CONCLUSION: Three-dimensional imaging may improve tibiofibular malreduction visualization in bimalleolar/trimalleolar/dislocated type Weber B fractures and in isolated type Weber C fractures with syndesmotic transfixation. The clinical impact of improving tibiofibular positioning remains highly questionable since there was no correlation between tibiofibular alignment and the clinical outcome at mid-term follow-up.

Therapeutic Management of a Substantial Pelvic Aneurysmatic Bone Cyst Including the Off-Label Use of Denosumab in a 35-Year-Old Female Patient.

Aneurysmal bone cysts (ABC) are benign bone tumors, which are highly vascularized. The main course of treatment is curettage followed by bone grafting or cement insertion. Still recurrence remains a main problem for patients. Denosumab is a monoclonal antibody, which acts as an inhibitor of the RANK/RANKL pathway, diminishing bone turnover. Recent case reports have shown that Denosumab can be a promising therapeutic agent for people suffering from therapy-resistant ABC. We report the case of a 35-year-old female patient presenting with a pronounced ABC of the pelvis. Since the tumor was inoperable, Denosumab was administered, leading to a significant shrinkage of the lesion, which allowed surgical intervention. Upon recurrence, Denosumab was restarted putting the patient once more into remission. Follow-up was four years overall with a clinical and radiological stable disease for fifteen months after final discontinuation of the monoclonal antibody. Therefore, our case further underlines the potential of Denosumab in the treatment of ABC.

[Salmonella osteomyelitis - a rare differential diagnosis of bone tumors]. / Salmonellenosteomyelitis ­ eine seltene Differenzialdiagnose eines Knochentumors.

This case describes a rare salmonella infection suspected to be an osseous lymphoma. A 27-year-old female presented herself with painful swelling of her knee, with prednisolone-treated Crohn's disease as her only pre-existing condition. Salmonella species group C were detected in the osseous material derived from an extraction. The disease was treated with intravenous ceftriaxone, oral cotrimoxazole as well as multiple debridements. The working diagnosis should thus always be questioned and bone pain in patients who are immunosuppressed should be further investigated.

Accuracy of Latarjet graft and screw position after using novel drill guide.

PURPOSE: For the success of Latarjet procedure a correct graft positioning is mandatory. Furthermore, the correct screw placement is important to avoid cartilage damage and soft tissue irritation. Due to a cadaveric experimental study, the accuracy of graft and screw positioning utilizing a novel drill guide for a minimal-invasive Latarjet procedure was analyzed. METHODS: Five human fresh-frozen shoulder specimens have been treated in accordance with the Congruent-Arc Latarjet technique using the glenoid bone loss set (Arthrex, Naples, FL, USA) with 3.75 mm cannulated screws throughout a 5 cm skin incision without detachment of the scapularis tendon. All procedures were performed by one single, experienced shoulder surgeon. The accuracy of graft and screw positioning was assessed due to a CT scan. RESULTS: A noticeable learning curve was noted during the study period as the first surgery took 45 min and the last 33 min. All grafts were correctly positioned with regard to the articular line of the glenoid surface. Impingement with the maximum head circumference was not encountered. The screw positions did not affect the suprascapular nerve. A damage of the graft was not noticed. CONCLUSIONS: The authors can recommend the usage of the new drill guide tested in this study. It seems to be beneficial in the Latarjet procedure and may ease correct graft positioning and prevent screw misplacement. Compared to fully arthroscopically performed Latarjet procedures it provides much steeper learning curve and seems technically easier and quicker to handle.

Cement augmentation versus extended dorsal instrumentation in the treatment of osteoporotic vertebral fractures: a biomechanical comparison.

AIMS: Loosening of pedicle screws is a major complication of posterior spinal stabilisation, especially in the osteoporotic spine. Our aim was to evaluate the effect of cement augmentation compared with extended dorsal instrumentation on the stability of posterior spinal fixation. MATERIALS AND METHODS: A total of 12 osteoporotic human cadaveric spines (T11-L3) were randomised by bone mineral density into two groups and instrumented with pedicle screws: group I (SHORT) separated T12 or L2 and group II (EXTENDED) specimen consisting of T11/12 to L2/3. Screws were augmented with cement unilaterally in each vertebra. Fatigue testing was performed using a cranial-caudal sinusoidal, cyclic (1.0 Hz) load with stepwise increasing peak force. RESULTS: Augmentation showed no significant increase in the mean cycles to failure and fatigue force (SHORT p = 0.067; EXTENDED p = 0.239). Extending the instrumentation resulted in a significantly increased number of cycles to failure and a significantly higher fatigue force compared with the SHORT instrumentation (EXTENDED non-augmented + 76%, p < 0.001; EXTENDED augmented + 87%, p < 0.001). CONCLUSION: The stabilising effect of cement augmentation of pedicle screws might not be as beneficial as expected from biomechanical pull-out tests. Lengthening the dorsal instrumentation results in a much higher increase of stability during fatigue testing in the osteoporotic spine compared with cement augmentation. Cite this article: Bone Joint J 2016;98-B:1099-1105.

[Cement augmentation on the spine : Biomechanical considerations]. / Zementaugmentation an der Wirbelsäule : Was ist biomechanisch zu beachten?

BACKGROUND: Vertebral compression fractures are the most common osteoporotic fractures. Since the introduction of vertebroplasty and screw augmentation, the management of osteoporotic fractures has changed significantly. AIMS: The biomechanical characteristics of the risk of adjacent fractures and novel treatment modalities for osteoporotic vertebral fractures, including pure cement augmentation by vertebroplasty, and cement augmentation of screws for posterior instrumentation, are explored. MATERIALS AND METHODS: Eighteen human osteoporotic lumbar spines (L1-5) adjacent to vertebral bodies after vertebroplasty were tested in a servo-hydraulic machine. As augmentation compounds we used standard cement and a modified low-strength cement. Different anchoring pedicle screws were tested with and without cement augmentation in another cohort of human specimens with a simple pull-out test and a fatigue test that better reflects physiological conditions. RESULTS: Cement augmentation in the osteoporotic spine leads to greater biomechanical stability. However, change in vertebral stiffness resulted in alterations with the risk of adjacent fractures. By using a less firm cement compound, the risk of adjacent fractures is significantly reduced. Both screw augmentation techniques resulted in a significant increase in the withdrawal force compared with the group without cement. Augmentation using perforated screws showed the highest stability in the fatigue test. DISCUSSION AND CONCLUSION: The augmentation of cement leads to a significant change in the biomechanical properties. Differences in the stability of adjacent vertebral bodies increase the risk of adjacent fractures, which could be mitigated by a modified cement compound with reduced strength. Screws that were specifically designed for cement application displayed greatest stability in the fatigue test.

[Finger injuries in ball sports]. / Fingerverletzungen beim Ballsport.

Ball sports are the most frequent cause of sport injuries and 60% of all hand injuries involve the fingers. The most common injury is closed rupture of the extensor tendon of the distal interphalangeal joint (mallet finger). Rupture of the deep flexor tendon (jersey finger) occurs particularly in contact ball sports, such as rugby. Injuries of the proximal interphalangeal and metacarpophalangeal joints are of high functional relevance. These injuries frequently represent complex lesions which are demanding both in diagnostics and therapy. Errors in diagnosis or insufficient treatment can lead to misalignment and functional impairment of the hand. This article provides an overview of the current treatment strategies and includes recommendations for the treatment of professional athletes.

[Suprapatellar approach to tibial medullary nailing with electromagnetic field-guided distal locking]. / Suprapatellarer Zugang zur Tibiamarknagelung mit magnetfeldgeführter, distaler Verriegelung.

Closed tibial shaft fractures are the domain of intramedullary nailing. With the introduction of new nail designs and technologies, even small, dislocated distal fragments can be anatomically aligned and safely fixed. Unsolved or to a lesser degree controlled are the problems of distal locking in the freehand technique, which can still be difficult and can lead to a significant radiation exposure, and how to control very short proximal tibial fragments in metaphyseal tibial fractures or tibial segmental fractures, where the proximal fracture line also runs through the metaphysis.By using a suprapatellar approach, i.e. a skin incision proximal to the patella with an entry point into the tibial bone from within the knee at the same site as for a standard infrapatellar approach, and then nailing the tibia in a semi-extended position, i.e. the knee is only flexed 10-20°, the intraoperative dislocation of a short proximal fragment can be avoided. The main indications for semi-extended tibial nailing are a short diaphyseal fragment in an isolated tibial shaft fracture, a segmental fracture where the proximal fracture line is metaphyseal and in patients where infrapatellar soft tissues are compromised.The use of the electromagnetic guidance system SureShot® generates reliable and reproducible results, reduces the operating time and is independent from radiation for distal locking.

[Primary meningococcal infection of the knee. A rare cause of septic arthritis]. / Primäre Meningokokkeninfektion des Kniegelenks. Eine seltene Ursache einer septischen Arthritis.

This article presents a case of primary septic arthritis of the knee due to serogroup C Neisseria meningitidis. A 19-year-old female presented to the emergency department with a painless but swollen knee joint which had started 2 days previously and fever (38 °C). The patient reported that she suddenly felt unwell 3 days ago and developed a rush at the same time which had almost disappeared when arrived at the emergency department. The patient was admitted to hospital and an antibiotic therapy was started with sulbactam and ampicillin. Initially, incubation of synovial fluid over the next 3 days did not result in detection of any pathogens; therefore, a reactive arthritis was assumed until Neisseria meningitidis was detected in cultures of the synovial fluid. Therapy was then switched to antibiotic therapy with ceftriaxon and arthroscopic irrigation was performed. The patient quickly recovered and was discharged from hospital after 14 days. This case example shows the difficulties of the clinical and microbiological diagnostics of a primary septic meningococcal arthritis; however, the treatment is relatively easy and mostly successful compared to other forms of bacterial joint infection.

Significance of clinical examination, CT and MRI scan in the diagnosis of posterior pelvic ring fractures.

INTRODUCTION: Patients with a fracture in the anterior pelvic ring often simultaneously demonstrate pain in the posterior pelvic ring. The aim of the present prospective study was to assess the sensitivity of CT, MRI and clinical examination in the detection of fractures in the posterior pelvic ring in patients with fractures of the anterior pelvic ring diagnosed in conventional radiographs. METHODS: Sixty patients with radiographic signs of an anterior pelvic ring injury were included in this prospective analysis. Following a focused clinical examination of the posterior pelvis, all patients underwent both a CT and then a MRI scan of their pelvis. Two board certified radiologists evaluated the CT and MRI scans independently. To estimate the presence of osteoporosis the Hounsfield units of the vertebral body of L5 were measured in each case. RESULTS: Fifty-three women and seven men, with a mean age of 74.7+/-15.6 years were included into the study. A fracture of the posterior pelvic ring was found in fourty-eight patients (80%) patients using MRI. Fractures of the posterior pelvic ring would have been missed in eight cases (17%), if only CT had been used. Eighty-five percent of the patients with a posterior fracture had an osteoporosis. The majority of the cases suffered from a low energy trauma. Thirty-eight patients (83%) with positive clinical signs at the posterior pelvic ring actually had a fracture of the posterior pelvic ring in the MRI. The clinical examination proved to be equally effective to CT in detecting posterior pelvic ring fractures. CONCLUSION: The significance of both, clinical examination and CT was confirmed in the detection of fractures in the posterior pelvic ring. MRI examination of the pelvis however, was found to be superior in detecting undislocated fractures in a cohort of patients with a high incidence of osteoporosis. Using MRI may be beneficial in select cases, especially when reduced bone density is suspected.

Percutaneous antegrade scaphoid screw placement: a feasibility and accuracy analysis of a novel electromagnetic navigation technique versus a standard fluoroscopic method.

BACKGROUND: Central screw positioning in the scaphoid provides biomechanical advantages. METHODS: A prospective randomized study of six fluoroscopically guided and six electromagnetically navigated screw (ENS) placements was performed on human cadavers. Accuracy of screw position was determined. Intraoperative fluoroscopy exposure times, readjustments of drilling directions, complete restarts and complications were documented. RESULTS: The ENS method provided a mean time benefit of 7.34 min compared with the standard method and the mean screw length ratio (SLR coronar: ENS 0.96 ± 0.04 mm, SFF: 0.92 ± 0.04 mm, P = 0.065; SLR sagittal: ENS 0.98 ± 0.02 mm, SFF: 0.91 ± 0.04 mm, P = 0.009) and the screw axis deviation angle (AD coronar: ENS 3.33 ± 2.34°, SFF: 10.33 ± 2.58°, P = 0.002; AD sagittal: ENS 2.83 ± 0.98°, SFF: 11.00 ± 6.16°, P = 0.002) were lower. Using the electromagnetic navigation procedure no drilling readjustments or restarts were required, no cortical breach occurred. CONCLUSIONS: Compared with the standard fluoroscopic technique, the ENS method used in this study showed higher accuracy, less complications, required less operation and radiation exposure time.

[Periprosthetic and interimplant femoral fractures: Biomechanical analysis]. / Periprothetische und interimplantäre Femurfrakturen : Biomechanische Analyse.

BACKGROUND: The requirements for treatment of femoral fractures are increasing with the rising age of the patients. The aim of this study was to evaluate femoral stiffness and the fracture risk after inserting different implants and implant combinations. METHODS: A total of 48 cadaveric femors were harvested and 8 groups were randomized on the basis of the bone mineral density (BMD). Different osteosyntheses following prosthetic stem implantation (hip and knee prostheses) were performed and compared with native femurs. All specimens were biomechanically tested in a four-point bending until fracture. RESULTS: The insertion of a femoral stem decreases the stiffness by approximately 33%. Ipsilateral retrograde nailing reduces the force to failure even more. This instable situation can be stabilized by a lateral locking compression plate. The most stable situation occurred in the presence of two cemented stems. CONCLUSION: Taken together these results clearly indicate that a hip prosthesis significantly weakens the femur, whereas two stems produce the most stable situation at all. The situation of a hip prosthesis and an retrograde nail should be avoided or covered by a bridging-osteosynthesis. In clinical practice an extramedullary fixation technique for distal femoral fractures should be preferred.

[New horizons for minimally invasive treatment of acromioklavikular joint injuries]. / Neue Horizonte zur minimal-invasiven Versorgung von Akromioklavikulargelenkverletzungen.

BACKGROUND: A novel radiation-free electromagnetic navigation system (ENS) method was developed and the feasibility and accuracy for transklavikular-transkorakoid drilling procedures were evaluated in an experimental setting. METHODS: In this study ten arthroscopically assisted, electromagnetically navigated transkorakoid-transklavikular drilling procedures with subsequent implantation of two TightRope® (Arthrex, Naples, FL.) devices (anatomical reconstruction) were performed on five human cadavers. Postoperative computed tomography (CT) scan analysis was carried out to determine tunnel placement accuracy. All procedures were performed without fluoroscopy. RESULTS: The mean overall operation time was 28.5 ± 6.6 min. Successful anatomical tunnel placement was achieved in 98.8 %. During the navigated drilling procedure no misguidance of the drill requiring directional readjustments or restarts occurred. No cortical breaches, fractures or complications occurred. CONCLUSION: The electromagnetically navigated transkorakoid-transklavikular drilling procedure used in this study demonstrated high targeting accuracy, required no intraoperative x-ray radiation and was associated with no complications.

[Fractures of the distal radius]. / Frakturen des distalen Radius.

The most prevalent fractures managed by trauma surgeons are those involving the distal radius. The injury occurs in two peaks of prevalence: the first peak around the age of 10 years and the second peak around the age of 60 years. Distal radius fracture management requires sensitive diagnostics and classification. The objectives of treatment are the reconstruction of a pain-free unlimited durable functioning of the wrist and avoidance of typical fracture complications. Non-operative conservative management is generally employed for stable non-displaced fractures of the distal radius with the expectation of a good functional outcome. Unstable comminuted fractures with intra-articular and extra-articular fragment zones are initially set in a closed operation and finally by osteosynthesis. An armament of surgical implants is available for instable fractures requiring fixation. Palmar locked plate osteosynthesis has been established in recent years as the gold standard for operative management of distal radius fractures. Complex Working Group on Osteosynthesis (AO) classification type 3 fractures require extensive preoperative diagnostics to identify and treat typical associated injuries around the wrist.

[The stoppa approach for treatment of acetabular fractures]. / Der Stoppa-Zugang zur Versorgung von Azetabulumfrakturen.

OBJECTIVE: The Stoppa approach in its modified form is an intrapelvine approach for the treatment of acetabular fractures. It is an alternative to the ilioinguinal approach. Goals are the gentle soft-tissue preparation, anatomic reduction and stable internal fixation. Here, the approach is described in detail together with possible expansion possibilities. INDICATIONS: The Stoppa approach in particular is used for the treatment of fractures of the anterior column with participation of the quadrilateral surface, transverse fractures, T-type fractures, but also 2-column fractures when the main pathology is located in anterior portions of the acetabulum. METHOD: This intrapelvic approach allows a direct view of the quadrilateral surface and the direct reduction of these fragments. In contrast to the ilioinguinal access the Stoppa approach dispenses with the preparation of the 2nd window with exposure of the vessels. The preparation is carried out via a Pfannenstiel access following transection of the median line alba. The further dissection is performed along the anterior pubic ramus, on the pelvic rim, towards the ipsilateral sacroiliac joint. CONCLUSION: The modified Stoppa approach is a soft-tissue-friendly approach for the treatment of acetabular fractures. With its options for expansion, possibility for osteotomy of the anterior superior iliac spine and the use of the first ilioinguinal window, almost all types of fractures of the acetabulum whose primary pathology is on the anterior side can be treated.

The role of inter-prosthetic distance, cortical thickness and bone mineral density in the development of inter-prosthetic fractures of the femur: a biomechanical cadaver study.

It is becoming increasingly common for a patient to have ipsilateral hip and knee replacements. The inter-prosthetic (IP) distance, the distance between the tips of hip and knee prostheses, has been thought to be associated with an increased risk of IP fracture. Small gap distances are generally assumed to act as stress risers, although there is no real biomechanical evidence to support this. The purpose of this study was to evaluate the influence of IP distance, cortical thickness and bone mineral density on the likelihood of an IP femoral fracture. A total of 18 human femur specimens were randomised into three groups by bone density and cortical thickness. For each group, a defined IP distance of 35 mm, 80 mm or 160 mm was created by choosing the appropriate lengths of component. The maximum fracture strength was determined using a four-point bending test. The fracture force of all three groups was similar (p = 0.498). There was a highly significant correlation between the cortical area and the fracture strength (r = 0.804, p < 0.001), whereas bone density showed no influence. This study suggests that the IP distance has little influence on fracture strength in IP femoral fractures: the thickness of the cortex seems to be the decisive factor.