[Osteoporotic bone fractures: intramedullary augmentation and hybrid osteosynthesis]. / Frakturen des osteoporotischen Knochens: intramedulläre Augmentation und Hybridosteosynthese.

The increasing number of people who are living longer and have a far more active lifestyle is inevitably associated with greater numbers of fractures. Stabilization of these fractures in older patients with plates and screws is complicated by fragile bone substance, especially in osteoporotic bone, since osteosynthesis with a conventional plate depends exclusively on the holding power of the screws. Therefore, treatment requires new stabilization technologies designed for these specific tasks. A small diameter polyethylene terephthalate (PET, Dacron®) balloon is delivered in a minimally invasive fashion and placed within the canal, transversing the fracture. Once positioned, the balloon is expanded with a liquid monomer to fill the medullary canal. The liquid monomer is then rapidly cured using visible blue light, forming a patient-customized intramedullary implant that stabilizes the entire length of the bone in contact with the implant. The described intramedullary implant can be easily drilled in any position or location, providing a substantial increase in screw holding power. Thus, a major advantage of the technique is the possibility to augment the newly formed balloon "nail" with a conventional plate and screws at the primary stabilization or at any later time.

[Photodynamic intramedullary bone stabilization of pathological fractures]. / Fotodynamische intramedulläre Knochenstabilisierung bei pathologischen Frakturen.

Pathological fractures of long tubular bones are stabilized with conventional implants. Essentially, plates and intramedullary nails are used for stabilization and are two different techniques, which compete with each other with respect to the surgical treatment. A large number of such means of osteosynthesis are commercially available but are primarily focused on acute fractures in otherwise biologically healthy bones. The pathological fracture or the treatment of impending pathological fractures due to metastatic osteolysis differs from the treatment of healthy bones in some fundamental aspects. The characteristics of pathological fractures make the development of new technologies that meet the specific needs of both the patient and the surgeon desirable. A new approach in treatment is stabilization of internal long bone fractures by the use of a cylindrical balloon implant, which is introduced into the bone via a small proximal or distal hole and then filled and expanded to a much larger diameter with a liquid monomer. The curing process is initiated with the application of blue light forming a rigid implant by polymerization (IlluminOss™). Many of the well-known disadvantages of conventional implants can be eliminated with this technology. Specifically, with respect to the irregular shape of the natural medullary canal it is possible to completely fill the medullary canal of the tubular bone. The filling of the canal provides torsional stability without the use of interlocking screws. Similarly, the use of the balloon technique enables minimally invasive surgery and furthermore permits the additive use of conventional metallic plates whenever necessary. The new balloon techniques show high primary stability in the treatment of pathological shaft fractures. In particular cases, the addition of a supplemental plate osteosynthesis is recommended.

Impact of posterior tibial nail malpositioning on iatrogenic injuries by distal medio-lateral interlocking screws. A cadaveric study on plastinated specimens.

In intramedullary tibial nailing, multi-planar locking makes stabilization of proximal and distal metaphyseal fractures possible. A known complication in intramedullary nailing of the tibia is iatrogenic injury to neuro-vascular structures caused by the insertion of locking screws. As shown in previous studies, the distal positioning of the nail is important, as it determines the course of the locking bolts. The goal of the present study was to display the consequences of posterior nail malpositioning with respect to the safety of the distal medio-lateral locking screws and the available options. Human cadaveric legs were plastinated according to the sequential plastination technique after intramedullary nailing of the tibia and were then cut transversely. The tibial nails were placed centrally or posteriorly. Macroscopic analysis showed a distinct drawback of posterior nail positioning, with diminished options for the placement of the locking screws and thereby a risk of damaging the anterior and posterior neuro-vascular bundles by distal medio-lateral locking screws.

Neuraminidases-Key Players in the Inflammatory Response after Pathophysiological Cardiac Stress and Potential New Therapeutic Targets in Cardiac Disease.

Glycoproteins and glycolipids on the cell surfaces of vertebrates and higher invertebrates contain α-keto acid sugars called sialic acids, terminally attached to their glycan structures. The actual level of sialylation, regulated through enzymatic removal of the latter ones by NEU enzymes, highly affects protein-protein, cell-matrix and cell-cell interactions. Thus, their regulatory features affect a large number of different cell types, including those of the immune system. Research regarding NEUs within heart and vessels provides new insights of their involvement in the development of cardiovascular pathologies and identifies mechanisms on how inhibiting NEU enzymes can have a beneficial effect on cardiac remodelling and on a number of different cardiac diseases including CMs and atherosclerosis. In this regard, a multitude of clinical studies demonstrated the potential of N-acetylneuraminic acid (Neu5Ac) to serve as a biomarker following cardiac diseases. Anti-influenza drugs i.e., zanamivir and oseltamivir are viral NEU inhibitors, thus, they block the enzymatic activity of NEUs. When considering the improvement in cardiac function in several different cardiac disease animal models, which results from NEU reduction, the inhibition of NEU enzymes provides a new potential therapeutic treatment strategy to treat cardiac inflammatory pathologies, and thus, administrate cardioprotection.

Impaired immune response mediated by prostaglandin E2 promotes severe COVID-19 disease.

The SARS-CoV-2 coronavirus has led to a pandemic with millions of people affected. The present study finds that risk-factors for severe COVID-19 disease courses, i.e. male sex, older age and sedentary life style are associated with higher prostaglandin E2 (PGE2) serum levels in blood samples from unaffected subjects. In COVID-19 patients, PGE2 blood levels are markedly elevated and correlate positively with disease severity. SARS-CoV-2 induces PGE2 generation and secretion in infected lung epithelial cells by upregulating cyclo-oxygenase (COX)-2 and reducing the PG-degrading enzyme 15-hydroxyprostaglandin-dehydrogenase. Also living human precision cut lung slices (PCLS) infected with SARS-CoV-2 display upregulated COX-2. Regular exercise in aged individuals lowers PGE2 serum levels, which leads to increased Paired-Box-Protein-Pax-5 (PAX5) expression, a master regulator of B-cell survival, proliferation and differentiation also towards long lived memory B-cells, in human pre-B-cell lines. Moreover, PGE2 levels in serum of COVID-19 patients lowers the expression of PAX5 in human pre-B-cell lines. The PGE2 inhibitor Taxifolin reduces SARS-CoV-2-induced PGE2 production. In conclusion, SARS-CoV-2, male sex, old age, and sedentary life style increase PGE2 levels, which may reduce the early anti-viral defense as well as the development of immunity promoting severe disease courses and multiple infections. Regular exercise and Taxifolin treatment may reduce these risks and prevent severe disease courses.

Treatment of displaced proximal fifth metatarsal fractures using a new one-step fixation technique.

BACKGROUND: Fractures of the tuberosity of the fifth metatarsal are common after foot twisting injuries, and operative treatment is recommended in cases of displacement. The purpose of this study was to report the radiologic outcome and clinical results of displaced fractures of the tuberosity of the fifth metatarsal treated using fine-threaded K-wires (FFS). METHODS: In 3 years' time, in a total of 35 cases, patients had an initial fracture displacement of more than 2 mm for isolated extraarticular fractures and an involvement of the cuboidal joint surface of more than 30%. After 15 months to 60 months (mean, 30.6), 32 of these patients participated in a clinical follow-up examination and questionnaire according to a clinical rating system for midfoot fractures. Radiologic outcome measurements were the remaining postoperative intraarticular step off and the healing time. RESULTS: The mean midfoot scale score was 96.5 points. All the patients returned to prior activities after operative treatment. Seven patients reported minor pain during longer periods of walking. One patient with secondary wound healing experienced frequent pain. Radiologically, in 32 of 35 patients, there was a remaining step off of less than 1 mm and in three patients less than 3 mm. All fractures except one healed within the first 3 months to 6 months. CONCLUSION: Operative treatment of displaced proximal fifth metatarsal fractures using the FFS system leads to a good clinical and radiologic outcome. The FFS system provides a new treatment option for this fracture type.

The Photodynamic Bone Stabilization System in the Treatment of Humerus Fractures: A Prospective Clinical Trial.

Background Fractures of the proximal humerus are among the most common long-bone fractures and present unique challenges to surgeons. Traditional internal fixation methods, such as intramedullary nails, are associated with drawbacks such as an inability to fully fill the trabecular space and a limited ability to utilize supplemental hardware in many cases. We evaluated the safety and effectiveness of a novel fracture fixation device that utilizes a light-cured monomer to stabilize the fracture in a cohort of patients suffering from humerus fractures. Methods We prospectively collected data from patients being treated surgically for humerus fractures. Fractures were treated using the photodynamic bone stabilization system (PBSS) consisting of a balloon and light-cured monomer. Patients were evaluated at 7-14, 30, 60, 90, 180, and 360 days post-procedure. Primary outcomes included normal and complete radiographic fracture healing. Secondary outcomes included pain (via visual analog scale), function (via the disability of the arm, shoulder, and hand (DASH) and constant shoulder scales), and the rate of complications. Results A total of 33 patients were included in the intent-to-treat analysis (mean age: 76.6 yrs). Of these patients, 88% demonstrated normal radiographic healing at their 90-, 180-, and 360-day visits. Complete radiographic healing was observed in 81%, 88%, and 96% of patients at 90, 180, and 360 days, respectively. Pain scores decreased significantly at day seven when compared with baseline (28.2+20.9 vs.53.6+32.2, p<0.001) and continued to decrease at the 90-day (24.7+15.5, p<0.001), 180-day (17.8+12.5, p<0.001) and 360-day (6.6+6.7, p<0.001) evaluations. DASH scores demonstrated statistically significant improvements over baseline (65.5+31.5) at 90 (37.0+14.9, p<0.001), 180 (30.6+15.7, p<0.001), and 360 days (23.9+15.0, p<0.001) post-procedure. The procedure-related event rate was 36.4%, with 5 (11.4%) device-related adverse events reported at the one-year follow-up. Conclusions Our study demonstrates the ability of a novel internal fixation device to safely and effectively treat fractures of the humerus in the elderly population.

Mechanical distraction for the treatment of posttraumatic stiffness of the elbow in children and adolescents. Surgical technique.

BACKGROUND: Elbow contracture is a recognized sequela of elbow injuries in children and adolescents, but previous studies of operative treatment with formal capsular release have demonstrated unpredictable outcomes and unfavorable results. METHODS: Over a period of five years, fourteen children and adolescents with a mean age of fourteen years who had posttraumatic stiffness of the elbow were managed according to a prospective protocol. Eleven patients had undergone a mean of three previous operative procedures before the index operation. After intraoperative distraction with an external fixator, there was a relaxation phase for six days followed by mobilization of the elbow joint under distraction in the fixator for a mean of seven weeks. Intraoperative range of motion under distraction reached a mean of 100 degrees . Open arthrolysis was not performed, but in four children impinging heterotopic bone was removed through a limited approach. Decompression of the ulnar nerve was performed in seven patients. RESULTS: The mean preoperative arc of total elbow motion was 37 degrees . The mean pronation was 46 degrees , and the mean supination was 56 degrees . After a mean duration of follow-up of thirty-four months, all patients but two had achieved an arc of motion of 100 degrees . The mean arc of flexion-extension was 108 degrees (range, 75 degrees to 130 degrees ). The mean range of pronation was 73 degrees (range, 20 degrees to 90 degrees ), and the mean range of supination was 75 degrees (range, 10 degrees to 90 degrees ). There were no pin-track infections or deep infections, and all elbows were stable. At the time of follow-up, three patients had radiographic evidence of humeroulnar degeneration. CONCLUSIONS: Closed distraction of the elbow joint with use of a monolateral external fixation frame with motion capacity yields more favorable results than other previously reported options for the treatment of posttraumatic elbow contractures in children and adolescents.

[The size and proportion of the interphalangeal finger joints: an anatomic study]. / Die Gelenkfläche und Größenverhältnisse der Fingergelenke: Eine anatomische Studie.

Background This study aimed to evaluate the size of the joint surfaces of the proximal and distal interphalangeal finger joints. Material and Methods 117 proximal and distal interphalangeal joints of 30 formalin-fixed hands of body donors were included in this study. The size of the articular surface was determined for each joint. Results The mean size of the proximal joint surface of the distal interphalangeal joint is 56.1 mm2; the distal joint surface averages 30.9 mm2 (ratio: 1.8:1). The size of the proximal articular surface of the proximal interphalangeal joint is 92.5 mm2. The size of the distal articular surface averages 52.4 mm2 (ratio 1.7:1). Conclusions This is the first study to describe the articular surface area of the proximal and distal interphalangeal joints of the hand.

Effective Management of Bone Fractures with the Illuminoss® Photodynamic Bone Stabilization System: Initial Clinical Experience from the European Union Registry.

The IlluminOss® system (IS) uses a light-curable polymer contained within an inflatable balloon catheter, forming a patient customized intramedullary implant. A registry was established in Germany and The Netherlands to prospectively collect technical and clinical outcomes in patients treated with IS for fractures of the phalange, metacarpal, radius, ulna, distal radius, fibula, clavicle and/or olecranon. Humeral, femoral, tibial and pelvic fractures were included under compassionate use. Procedural success included successful placement of the device at the target fracture site and achievement of fracture stabilization. Clinical and radiographic assessments were made postoperatively through 12 months. One hundred thirty two patients (149 fractures) were enrolled with most fractures (85%) resulting from low-energy trauma. Simple fractures predominated (47%) followed by complex (23%) and wedge (16%) fractures. Procedural success was achieved in all patients and no implants required removal or revision. Normal range of motion was realized in 87% of fractures. Radiographically, there was substantial cortical bridging, total dissolution of the fracture line, and complete fracture healing. Across a variety of fracture types, the IS provides a safe and effective approach for rapid healing and functional recovery.

Mechanical distraction for the treatment of posttraumatic stiffness of the elbow in children and adolescents.

BACKGROUND: Elbow contracture is a recognized sequela of elbow injuries in children and adolescents, but previous studies of operative treatment with formal capsular release have demonstrated unpredictable outcomes and unfavorable results. METHODS: Over a period of five years, fourteen children and adolescents with a mean age of fourteen years who had posttraumatic stiffness of the elbow were managed according to a prospective protocol. Eleven patients had undergone a mean of three previous operative procedures before the index operation. After intraoperative distraction with an external fixator, there was a relaxation phase for six days followed by mobilization of the elbow joint under distraction in the fixator for a mean of seven weeks. Intraoperative range of motion under distraction reached a mean of 100 degrees. Open arthrolysis was not performed, but in four children impinging heterotopic bone was removed through a limited approach. Decompression of the ulnar nerve was performed in seven patients. RESULTS: The mean preoperative arc of total elbow motion was 37 degrees. The mean pronation was 46 degrees, and the mean supination was 56 degrees. After a mean duration of follow-up of thirty-four months, all patients but two had achieved a functional arc of motion of 100 degrees. The mean arc of flexion-extension was 108 degrees (range, 75 degrees to 130 degrees). The mean range of pronation was 73 degrees (range, 20 degrees to 90 degrees), and the mean range of supination was 75 degrees (range, 10 degrees to 90 degrees). There were no pin-track infections or deep infections, and all elbows were stable. At the time of follow-up, three patients had radiographic evidence of humeroulnar degeneration. CONCLUSIONS: Closed distraction of the elbow joint with use of a monolateral external fixation frame with motion capacity yields more favorable results than other previously reported options for the treatment of posttraumatic elbow contractures in children and adolescents.

Shortening and deformity of radius and ulna in children: correction of axis and length by callus distraction.

Forearm deformities in children and adolescents may be congenital or developmental, or result from trauma; they may cause pain and decreased function of the wrist and hand. In this study we treated seven patients with forearm deformities (10 forearms) by callus distraction of either the radius or ulna using a monolateral external fixator after osteotomy. Target length was achieved in all cases. The results show significant improvement in range of motion of the forearm. All patients were satisfied with the appearance. There were no complications such as pin tract infection or neural impairment. In one case delayed ossification was resolved by alternating distraction and compression. The timing of correction depends on the implications of the deformity for the carpal bones and the function of the other forearm. Monolateral external fixation proved a versatile tool for correction of forearm deformity in children and adolescents, with a low complication rate.

Reconstruction of Mason type-III and type-IV radial head fractures with a new fixation device: 23 patients followed 1-4 years.

BACKGROUND: Treatment options in radial head fractures of Mason types III and IV range from open reduction and internal fixation (ORIF) to radial head resection with or without prosthetic replacement. PATIENTS: In a prospective study, the radiographic and clinical outcome was evaluated in 23 patients (age median 51 years) with 23 complex radial head fractures median 2 (1-4) years after ORIF using a new fixation device (FFS; Orthofix). 14 Mason type-III fractures with 2 concomitant olecranon fractures and 1 ulnar nerve lesion, and 11 type-IV fractures with 2 olecranon fractures and 2 fractures of the coronoid process were treated. 2 patients were lost to follow-up. In 7 cases of joint instability, an elbow fixator with motion capacity was applied after ORIF of the radial head. RESULTS: No radial head resection was necessary. No secondary dislocations or nonunion occurred. The Morrey elbow score was excellent in 8 and good in 4 Mason type-III fractures and excellent in 5, good in 3, and fair in 3 Mason type-IV fractures. INTERPRETATION: Reconstruction of comminuted radial head fractures can be performed with this device and radial head resection can be avoided.