Chemical Compounds Released from Specific Osteoinductive Bioactive Materials Stimulate Human Bone Marrow Mesenchymal Stem Cell Migration.

In this work, a poly(L-lactide-co-glycolide) (PLGA)-based composite was enriched with one of the following sol-gel bioactive glasses (SBG) at 50 wt.%: A1-40 mol% SiO2, 60 mol% CaO, CaO/SiO2 ratio of 1.50; S1-80 mol% SiO2, 20 mol% CaO, CaO/SiO2 ratio of 0.25; A2-40 mol% SiO2, 54 mol% CaO, 6 mol% P2O5, CaO/SiO2 ratio of 1.35; S2-80 mol% SiO2,16 mol% CaO, 4 mol% P2O5, CaO/SiO2 ratio of 0.20. The composites and PLGA control sheets were then soaked for 24 h in culture media, and the obtained condition media (CM) were used to treat human bone marrow stromal cells (hBMSCs) for 72 h. All CMs from the composites increased ERK 1/2 activity vs. the control PLGA CM. However, expressions of cell migration-related c-Fos, osteopontin, matrix metalloproteinase-2, C-X-C chemokine receptor type 4, vascular endothelial growth factor, and bone morphogenetic protein 2 were significantly increased only in cells treated with the CM from the A1/PLGA composite. This CM also significantly increased the rate of human BMSC migration but did not affect cell metabolic activity. These results indicate important biological markers that are upregulated by products released from the bioactive composites of a specific chemical composition, which may eventually prompt osteoprogenitor cells to colonize the bioactive material and accelerate the process of tissue regeneration.

The role of vasculature in bone development, regeneration and proper systemic functioning.

Bone is a richly vascularized connective tissue. As the main source of oxygen, nutrients, hormones, neurotransmitters and growth factors delivered to the bone cells, vasculature is indispensable for appropriate bone development, regeneration and remodeling. Bone vasculature also orchestrates the process of hematopoiesis. Blood supply to the skeletal system is provided by the networks of arteries and arterioles, having distinct molecular characteristics and localizations within the bone structures. Blood vessels of the bone develop through the process of angiogenesis, taking place through different, bone-specific mechanisms. Impaired functioning of the bone blood vessels may be associated with the occurrence of some skeletal and systemic diseases, i.e., osteonecrosis, osteoporosis, atherosclerosis or diabetes mellitus. When a disease or trauma-related large bone defects appear, bone grafting or bone tissue engineering-based strategies are required. However, a successful bone regeneration in both approaches largely depends on a proper blood supply. In this paper, we review the most recent data on the functions, molecular characteristics and significance of the bone blood vessels, with a particular emphasis on the role of angiogenesis and blood vessel functioning in bone development and regeneration, as well as the consequences of its impairment in the course of different skeletal and systemic diseases.

Lower limb injuries in american football players in Poland.

BACKGROUND: The aim of the study was to determine the location and types of injuries in the lower limbs in American football players in Poland. The circumstances of the injuries were identified, with particular emphasis on the player's position on the field. METHODS: Original questionnaire to investigate 70 consecutive Polish players was used. Analyses as a whole and divided into offensive and defensive players were carried out. RESULTS: Overall, injuries to both lower limbs accounted for 17.1%, injuries to the right lower limb to 37.2%, and injuries to the left limb to 29%. Ankle injuries were the most common, both offensive and defensive, accounting for 58.5% and 48.3% of lower limb injuries, respectively. Injuries to muscles, tendons and ligaments were more common in defensive players (55.2%), while in offensive sprains (52.5%), fractures (19.5%), and contusions (17.1%). The incidence of lower limb injuries was higher in general during training than competitions and in the case of offensive players (14.6%). CONCLUSIONS: Coaching American football increases the risk of foot injury, accounting for 10% of lower limb injuries. The obtained results indicate the need to strengthen the ligamentous-muscular complex of the lower limbs. Lower limb injuries are more common among offensive players than defensive. Offensive players are twice as likely to suffer from foot injuries. Lower limb injuries are more common during training, compared to competitions, both offensively and defensively.

Treatment of reverse obliquity intertrochanteric fractures.

BACKGROUND: Unstable intertrochanteric fractures of the hip, especially reverse oblique fractures are a serious problem in traumatology, as there is no standard method of treatment and inadequate treatment carries a significant complication rate. To assess the surgical treatment results of reverse oblique trochanteric fractures. MATERIAL/METHODS: Between 1997-2010, 389 patients with intertrochanteric fractures were treated. 28 (7.1%) of these fractures classified as reverse oblique. This group of patients consisted of 10 men and 18 women, aged 24 to 98 years. All patients underwent surgery. Following treatment options were used; dynamic hip screw (DHS)--10 patients, proximal femoral nail (PFN)--13 patients, dynamic condylar screw (DCS)--2 patients, angular plate--4 patients, UFN spiral blade--1 patient, bone plate--1 patient. Since 2000, all patients with reverse oblique fractures were treated with a PFN. RESULTS: Seventeen (60.7%) hips healed without complications. In three patients fixation was unsuccessful. The first patient, who was unhealed because of non-union, underwent three types of fixation (DHS, DCS and PFN) before finally receiving a total revision cement prosthesis. The second patient suffered a re-fracture following angular plate procedure and fixation was changed into a DHS. The third patient, treated with DCS, healed with a varus deformity. Twelve out of thirteen PFN-treated hips healed without complications. Six patients died a few years after surgery due to unrelated causes. CONCLUSIONS: The operative treatment of reverse oblique fractures using intramedullary fixation carries fewer complications than internal extramedullary fixation.

Relationship between the hip range of motion and functional motor system movement patterns in football players.

BACKGROUND: The aim of this study was to determine the hip range of motion and the movement patterns of football players assessed with an aid of a Functional Motor Systems test, and to find an association between these parameters and the risk for hip joint injury. METHODS: The study included 50 men aged between 16 and 20 years: 25 footballers and 25 age- and body mass index-matched controls. The hip ranges of motion (flexion, extension, internal and external rotation, adduction and abduction) were determined, and the movement patterns were evaluated with the tests from the Functional Motor Systems battery. RESULTS: Football players presented with significantly higher ranges of the hip flexion, extension, internal and external rotation than the controls. Moreover, footballers and controls differed significantly in terms of their mean overall Functional Motor Systems scores (15.77 points ±2.44 vs. 13.79±3.02 points, P=0.019). Football players scored best on the shoulder mobility test for the right side and worst on the rotary stability test for the left side. The scores on the trunk stability test and rotary stability test for the left side were significantly higher in footballers than in the controls. Nevertheless, the overall Functional Motor Systems scores of 14 points or less were recorded in the case of as many as 10/25 footballers. CONCLUSIONS: Altogether, these findings suggest that some football players present with a strain which may predispose them to future injuries. Future research should center around the etiology of reduced hip ROM observed in footballers. Furthermore, football training seems to result in a considerable motor asymmetry of the trunk which also predisposes to injury.

The role of CaO/SiO2 ratio and P2O5 content in gel-derived bioactive glass-polymer composites in the modulation of their bioactivity and osteoinductivity in human BMSCs.

We obtained a range of PLGA-based composites containing sol-gel bioactive glasses (SBG) from the SiO2-CaO and SiO2-CaO-P2O5 systems. Eight SBGs with different CaO/SiO2 ratios with and without P2O5 were incorporated at 50% w/w to PLGA matrix and structured into thin films suitable for cell culture. The SBG/PLGA composites were examined for their bioactivity in simulated body fluid (SBF), ion release profile in culture media with and without cells, and osteoinductivity in standard human bone marrow stromal cell (hBMSC) cultures without osteogenic growth factors. Our results indicate different surface activity of composites depending on the presence/absence of P2O5 in SBG composition. Furthermore, ion release profile to culture medium differed depending on the presence/absence of cells. Direct culture of hBMSC on the SiO2-CaO/PLGA composite films resulted in elevated Runx-2 mRNA, opposite to low Runx-2 mRNA levels on SiO2-CaO-P2O5/PLGA films. All studied composites increased Osx mRNA levels. Whereas some of SiO2-CaO/PLGA composites did not elevate BMP-2 and -6 proteins in hBMSC cultures, high levels of these BMPs were present in all cultures on SiO2-CaO-P2O5/PLGA composites. All composites induced BMP-related Tak1 signalling, whereas Smad1 signalling was restricted mostly to composites containing three-component SBGs. ALP activity of hBMSC and BMP-related luciferase activity of mouse BRITE cells differed depending on whether the cells were stimulated with culture medium conditioned with SBG/PLGA composites or the cells were directly cultured on the composite surfaces. Altogether, beyond bioactivity and osteoinductivity of SBG/PLGA composites, our studies show key differences in the biological response to both the bioactive material dissolution products and upon direct cell-material contacts.

In vitro osteogenic potential of collagen/chitosan-based hydrogels-silica particles hybrids in human bone marrow-derived mesenchymal stromal cell cultures.

The aim of this study was to assess osteogenic potential of three groups of biopolymeric hydrogel-based surfaces made of plain collagen, chitosan or collagen/chitosan, crosslinked with genipin or all three biopolymers modified with silica particles of two sizes (S1=240nm and S2=450nm). Biocompatibility and osteoinductive properties of the resulting composites were analyzed in the human bone marrow-derived mesenchymal stromal cells (hBMSCs) in vitro cultures. It was revealed that all tested materials are biocompatible and significantly enhance ALP activity in hBMSCs which was particularly pronounced for collagen/chitosan based hybrids. Gene expression (RUNX-2, COL-I, OC and VEGF mRNA) analyses performed in hBMSCs cultured at collagen/chitosan materials showed that ColChS1 hybrid the most effectively promotes osteogenic differentiation of hBMSCs. SEM and EDS analyses of materials carried out after 20days of hBMSCs culturing on ColCh-based hydrogels revealed that the hybrid materials enhanced hBMSCs-mediated mineralization of ECM. Our studies revealed that collagen/chitosan hydrogels modified with silica particles of smaller sizes (ColChS1) exhibit high pro-osteogenic properties without the need of applying any additional osteogenic inducers. That suggests that ColChS1 having the intrinsic osteoinductive activity holds great potential as material of choice for bone regeneration procedures, especially in regeneration of small bone losses.

Use of reamed locked intramedullary nailing in the treatment of aseptic diaphyseal tibial non-union.

BACKGROUND: Tibial fractures have been associated with the highest rates of bone union disturbances for many years. Stabilization of the tibial shaft with a reamed intramedullary nail is now being increasingly recommended as a treatment of choice. The aim of this study was to evaluate the outcomes of treatment of tibial shaft non-union with reamed intramedullary nails locked distally and proximally. MATERIAL AND METHODS: Thirty-three patients (11 females and 22 males) with tibial shaft non-union were treated by locked intramedullary nailing. There were twelve patients with a biologically active non-union, while in the remaining 21 the non-union was biologically non-active. The diagnosis was based on case history, physical examination and X-ray data. The average non-union time was 26.96. An intramedullary nail was inserted according to the technique recommended by AO/ASIF. Follow-up examinations were performed at six-week intervals until bone union was obtained. The diagnosis of bone union was based on physical examination and X-ray evidence. The functional outcome was assessed according to the Johner-Wruhs scale. Treatment failure was defined as the absence of clinical and radiological signs of bone union 12 months after surgery. RESULTS: Bone union was achieved in 94% patients following an average time of 37.2 weeks. The functional outcome was classified as good or very good according to the Johner and Wruhs scale in 60% of the patients, while 18% of the patients were diagnosed to have a poor functional outcome. An infection of the non-union site was found in 6 patients, of whom two developed a chronic infection (in one patient bone union was not achieved). CONCLUSION: The treatment of an aseptic non-union of the tibial shaft with an intramedullary nail is an effective procedure. This conclusion must be regarded as tentative in view of the small sample size.

Treatment of femoral shaft union disturbances with intramedullary nailing. Treatment failure.

BACKGROUND: The paper contains an analysis of the treatment outcomes of intramedullary nailing for femoral shaft non-union. MATERIALS AND METHODS: Twenty-two patients were treated between 1999 and 2005 with locked intramedullary nailing for femoral shaft non-union. The average age was 38.2 years (range 17-79). The study group comprised 20 males and 2 females. The right femur was affected in 12 patients, and the left in 10 patients. All patients had undergone multiple operations to treat the non-union. At the time of the study, non-union had been present for a period ranging from 9 months to as much as 10 years. Stabilisation with an intramedullary nail was preceded by reaming of the medullary cavity. Nails of different diameter were used (11-16 mm, usually 11 or 13 mm). Both static and dynamic locking was used. Surgery was confined to stabilization with an intramedullary nail in 13 patients, and 9 patients additionally underwent the Judet-Forbes decortication procedure, bone grafting or internal plate fixation and osteomuscular decortication. RESULTS: The non-union healed in 19 patients and was not achieved in the remaining 3. A detailed analysis was performed in 9 cases in which the bone union was not achieved despite reaming the medullary cavity, nailing and additional procedures, which did not lead to bone healing in 3 patients. CONCLUSIONS: Despite being an acknowledged method of treatment for delayed union of long-bone shafts, intramedullary nailing following reaming of the medullary cavity did not result in bone healing in all of our patients and additional procedures were often required. Therefore, the use of this procedure for femoral shaft pseudoarthroses should be decided on a case-by-case basis.

Activity and Quality of Life after Total Hip Arthroplasty.

BACKGROUND: Coxarthrosis is a chronic musculoskeletal condition that causes severe pain and considerable limi-tation of the patient's motor performance. Total hip arthroplasty is one of the most common and effective methods used in the treatment of advanced degenerative changes. The aim of the present study was to evaluate the activity and quality of life of patients after unilateral total hip arthroplasty. MATERIAL AND METHODS: The study was conducted in a group of 189 patients who had undergone unilateral total hip arthroplasty. Goniometry was used to determine the range of motion of both hip joints. Patients' physical ability and pain severity were assessed based on the Harris Hip Score (HHS) questionnaire. RESULTS: The examination of the range of motion in the lower extremities revealed statistically significant diffe-rences in flexion (p<0.01), abduction (p=<0.01), adduction (p<0.01) and external rotation (p<0.01) between the operated and the healthy extremity. The greatest limitation of motion was demonstrated for external rotation (<14°). Approximately 14% of the patients were not able to perform this motion in their healthy hip joint, while 17.5% of them could not do so in the affected hip joint. Analysis of HHS results (mean = 79 pts) revealed that more than 50% of the patients described their functional ability and quality of life as good and excellent. It was demonstrated that 54% of patients did not suffer from pain, whereas minor or mild pain was noted in 35%. CONCLUSIONS: 1. A subjective clinical assessment of patients after total hip arthroplasty showed that their quality of life had improved. 2. It is necessary to perform physiotherapy after total hip arthroplasty, on both the operated and healthy side. 3. Exacerbation of pain and impaired activity in patients after total hip arthroplasty were associated with the female sex to a considerable extent.

Kinetic and kinematic characteristics of natural velocity gait in anterior cruciate ligament-deficient patients.

This study evaluates changes in the knee following anterior cruciate ligament (ACL) injuries by presenting the kinematic characteristics of the ankle and hip joints and the pelvis, and assessing the dynamic forces applied by knee joint muscles under isokinetic conditions to identify compensatory mechanisms. Seventeen ACL-deficient males, 16-47 years of age, participated in the study, and measurements were taken an average of 24.4 months after their injuries occurred. Vicon, a three-dimensional motion analysis system, was used to examine the participants' locomotive characteristics. Isokinetic tests were carried out using Easytech Genu 3 at two velocities 60 and 180°/s. We found that deviations from normal gait were most common in the ACL-deficient knee, and that there was also a noticeable impact on the functioning of other joints in the same limb. However, even chronic knee joint laxity did not result in a considerable change in a participant's gait stereotype. Measurements showed a reduction in muscular strength in knee joint extensors and flexors in isokinetic contraction in the developed joint moments of the muscle groups under research compared with the healthy limb.

Degradation, bioactivity, and osteogenic potential of composites made of PLGA and two different sol-gel bioactive glasses.

We have developed poly(L: -lactide-co-glycolide) (PLGA) based composites using sol-gel derived bioactive glasses (S-BG), previously described by our group, as composite components. Two different composite types were manufactured that contained either S2-high content silica S-BG, or A2-high content lime S-BG. The composites were evaluated in the form of sheets and 3D scaffolds. Sheets containing 12, 21, and 33 vol.% of each bioactive glass were characterized for mechanical properties, wettability, hydrolytic degradation, and surface bioactivity. Sheets containing A2 S-BG rapidly formed a hydroxyapatite surface layer after incubation in simulated body fluid. The incorporation of either S-BG increased the tensile strength and Young's modulus of the composites and tailored their degradation rates compared to starting compounds. Sheets and 3D scaffolds were evaluated for their ability to support growth of human bone marrow cells (BMC) and MG-63 cells, respectively. Cells were grown in non-differentiating, osteogenic or osteoclast-inducing conditions. Osteogenesis was induced with either recombinant human BMP-2 or dexamethasone, and osteoclast formation with M-CSF. BMC viability was lower at higher S-BG content, though specific ALP/cell was significantly higher on PLGA/A2-33 composites. Composites containing S2 S-BG enhanced calcification of extracellular matrix by BMC, whereas incorporation of A2 S-BG in the composites promoted osteoclast formation from BMC. MG-63 osteoblast-like cells seeded in porous scaffolds containing S2 maintained viability and secreted collagen and calcium throughout the scaffolds. Overall, the presented data show functional versatility of the composites studied and indicate their potential to design a wide variety of implant materials differing in physico-chemical properties and biological applications. We propose these sol-gel derived bioactive glass-PLGA composites may prove excellent potential orthopedic and dental biomaterials supporting bone formation and remodeling.

Gel-derived bioglass as a compound of hydroxyapatite composites.

Despite the excellent biocompatibility of hydroxyapatite and bioglass, their clinical applications are limited to non-load-bearing implants and implant coatings due to their low mechanical properties. We have developed two different composites made of hydroxyapatite (HA) and gel-derived bioglasses designated S2 (80 mol% SiO(2)-16 mol% CaO-4 mol% P(2)O(5)) or A2 (40 mol% SiO(2)-54 mol% CaO-6 mol% P(2)O(5)). We show that the combination of hydroxyapatite with either bioglass results in better composite bioactivity and biocompatibility compared to HA alone. We used a commercially available hydroxyapatite that was sintered with varying additions (10%, 50%) of A2 or S2 bioglass. Scanning electron microscopy and x-ray diffraction were used to characterize the microstructure and phases of the composites. The elastic properties of bioglass/HA composites were analyzed with the use of the pulse ultrasonic technique. The bioactivity (surface activity) of the composites was assessed by determining the changes of surface morphology and composition after soaking in simulated body fluid (SBF) for 7 and 14 days. The biocompatibility of the obtained composites was then assessed in vitro using adult human bone marrow stromal cells. Cells were seeded on the material surfaces at a density of 10(4) cells cm(-2) and cultured for 7 days in non-differentiating and osteogenic conditions. The number of live cells was estimated in both standard and osteogenic cultures, followed by alkaline phosphatase (ALP) activity assay in osteogenic cultures. We determined that 10 wt% addition of A2 (E = 12.24 GPa) and 50 wt% addition of S2 (E = 16.96 GPa) to the HA base results in higher Young's modulus of the composites compared to pure hydroxyapatite (E = 9.03 GPa). The rate of Ca-P rich layer formation is higher for bioglass/HA composites containing A2 bioglass compared to the composites containing S2 bioglass. Evaluation of cell growth on the bioglass/HA composites showed that the incorporation of either 50 wt% S2 or 50 wt% A2 into the hydroxyapatite base significantly improves cell viability when compared to cells grown on pure HA. Also the cellular activity of ALP, an early marker of osteoblasts, increases with the amount of bioglass addition to the composites.

[Interlocking intramedullary nail with reaming of bone marrow cavity in treatment of tibia and femur pseudarthrosis]. / Blokowany gwózdz sródszpikowy z rozwiercaniem jamy szpikowej w leczeniu stawów rzekomych kosci udowej i piszczelowej.

The aim of this paper was to assess the results of treatment of pesudoarthrosis of the tibia and femur with reamed interlocked intramedullary nailing. A group of 17 patients with pseudoarthrosis of long bones were treated. Pseudoarthrosis were located in 10 cases in the tibia and in 7 cases in the femur. In the analysed group there were 14 male and 3 female patients (average age: 48 years). All patients were treated by locked intramedullary nailing. Complete bone union was observed in 15 cases, 1 case is still under observation (radiological signs of bone union are already evident) and in 1 case treatment failed to resolve the pseudoarthrosis. Intramedullary interlocking nailing in the treatment of long bone pseudoarthrosis give very good stability and creates very good conditions for blood vessel penetration between the bone fragments. The reaming procedure yields biologically active material that accelerates the bone union process.

[Revision arthroplasty in aseptic loosening of cemented sockets of hip prosthesis]. / Wymiana aseptycznie obluzowanych panewek cementowych stawu biodrowego.

The aim of this paper was to assess early results of revision arthroplasty in aseptic loosening of cemented sockets. A group of 67 patients (53 females and 14 males) age ranging from 47 to 78 years (average: 72 years) who underwent revision arthroplasty because of aseptic loosening of cemented sockets. Early surgical treatment can spare the patient from a risky procedure and lead to better end results. In cases with massive bone destruction of the pelvis good results can be achieved by using bone grafts and anti-protrusion cages.