Avascular necrosis (AVN) is a disorder leading to femoral head (FH) destruction, while BMPs are known for their osteogenic ability. In this study we analyzed BMP-2, BMP-4, BMP-6 and BMP-7 expression at the RNA and protein level in the normal and necrotic sites of the FHs. Quantitative RT-PCR for BMP-2,-4,-6,-7 genes was performed in samples from the normal and necrotic sites of 52 FHs with AVN. Protein levels of BMP-2,-4,-6 were estimated by Western Blot analysis. Statistical analysis was performed using the t-test (p<
0.05). BMP-2 and BMP-6 mRNA levels were higher in the normal than the necrotic site (BMP-2 and BMP-6, normal vs necrotic: 16.8 vs 7.5 and 2 vs 1.66, respectively). On the contrary, BMP-4 mRNA levels were higher in the necrotic (1.2) than the normal site (0.97), while BMP-7 mRNA levels were low in both sites. At the protein level, BMP-2 expressed higher in the normal (0.63) than the necrotic region (0.58), while BMP-4 and BMP-6 detected at higher levels in the necrotic site (BMP-4 and BMP-6, normal vs necrotic: 0.51 vs 0.61 and 0.52 vs 0.57, respectively). Different mRNA levels between the normal and necrotic site, as well as discrepancies between the gene and protein BMPs expression levels suggest a different regulation mechanism between the two regions. Better understanding of the expression pattern of BMPs could lead to a more successful use of these molecules in the prevention and treatment of AVN
Periosteum is a specialized connective tissue that surrounds bone, containing progenitor cells that develop into osteoblasts. The osteo-progenitor cells along with growth factors, such as BMPs, play critical role in development, reconstruction and bone formation. Aim: to evaluate the expression of BMPs in human periosteum and in different subrgroups, including different donor sites, gender, and smoking habits. Gene expression of BMPs 2,4,6,7 was performed in 60 periosteal samples using quantitative RT-PCR. Samples were obtained from 32 men/28 women, 22 smokers/38 non-smokers, 29 lower/31 upper extremities. BMP2 gene expression was significantly higher (median: 12.02, p<
0.05) than the mRNA levels of BMPs 4,6,7 (median: 1.36, 2.55, 0.04) in all samples. BMP2 mRNA levels were higher in large compared to small bones (median: 13.4 vs 9.48), while BMPs 4,6,7 gene expression was similar (1.3 vs 1.4, 2.7 vs 2.1, 0.04 vs 0.03, respectively). In lower extremities, BMPs mRNA levels were higher than in the upper; the same was detected in non-smokers versus smokers group (BMPs2,4,6,7: 13.9 vs 1.5, 3.1 vs 0.048, 8.7 vs 1.06, 1.6 vs 0.026, respectively). mRNA transcripts of BMP2 were higher in men than women (median: 13.1 vs 10.8). In our study, BMP2 expression is characteristically higher than that of BMP4, BMP6 and BMP7, highlighting the critical role that BMP2 plays in bone homeostasis. Furthermore, the elevated expression of BMP2 in men towards women, and of all BMPs of the lower extremity samples indicate the effect of hormones and mechanical factors in periosteal BMPs gene regulation; while the effect of smoking is reflected in the reduction of BMPs expression in smokers.
We evaluated the contribution of specific gene polymorphisms of IL-1a/IL-1R/IL-1RA/IL-4Ra/IL-1b/IL-12/γIFN/TGF-b/TNF-a/IL-2/IL-4/IL-6/IL-10 cytokines in patients with AVN. DNA was extracted from 112 patients and 238 healthy Greek individuals. DNA analysis was performed by the PCR-SSP method and the use of the Protrans kit. Statistical analysis was performed by χ2 test. In the patients, the TC frequency of the IL-1a (nt-889) was 52% while in normal was 40%. The C/G allele frequency of TGF-b codon 25 in patients was 9% C and 91% G vs 13% C and 87% G in normal. At position −238 of TNFa, 11% of the patients had the GA genotype in contrast to 1% of the controls. The GG/GG haplotype of TNFa gene promoter (nt. −308 and −238) was more frequent in both groups, while the GG/GA haplotype detected in 9% and 1% of the patients and controls, respectively. At the −1082 position of the IL-10 gene, the GG genotype was detected in 15% of the controls and 7% of the patients. Also, the GCC/GCC haplotype in IL-10 (positions -1082/-819/-592) was higher in the controls (15%) than the patients (7%). The genotypes TC (nt-889) of IL-1a, GC (codon 25) of TGF-b, GC (nt-1082) of IL-10 and GA (nt −238) of TNFa, are more prevalent in the patients than the healthy individuals (p<
0.05). Based on our results, the presence of one of the above mentioned polymorphisms or the simultaneous carriage of more than one may contribute to the risk for osteonecrosis
Quantitative RT-PCR was performed for OPG, RANKL and RANK molecules by using the Light Cycler FastStart DNA Master Hybridization Probes kit (Roche). Western Blotting: 22 bone tissues were run on 4–12% NuPAGE gel (Invitrogen). Anti-OPG, anti-RANKL and anti-actin antibodies were used and membranes were immersed in ECL.
Western Blotting analysis: Normal sites from all FHs showed comparable OPG protein levels (median: 0.57) which were similar to those of normal (median: 0.63). Similar pattern to that of OPG was observed also for RANKL protein expression, where the median value for RANKL/F-actin ratio was 0.49 and 0.5 in normal and necrotic sites of FHs, respectively.
The purpose of our study is to evaluate the expression of periosteal BMPs mRNA from fracture samples, collected within 24 hours of fracture and to compare it with BMPs expression from periosteal samples of normal (non-fractured) bones.
This represents a paradigm shift in our understanding of NWPT and that these dressings should be used with caution on tissues with compromised perfusion.
Foot osteomyelitis is a common problem for which management is variable and few guidelines exist. To present our treatment protocol and the results in 36 patients (20 men, 16 women, mean age: 49.5 years) with osteomyelitis distal to the ankle, followed up for 17.6 months (range: 3–64). Bone infection involved toes (n=4), lesser metatarsals (n=11), hallux (n=3), midfoot (n=4), calcaneus (n=9), whereas 4 cases presented as generalised osteomyelitis. Postoperative infection was the cause in 10 cases. Eleven patients were classified as host-type A, 14 as B and 11 as C. A draining sinus was present in 28 cases. The treatment protocol included surgical debridement, the bead-pouch technique for local antibiotic administration and closure primarily (n=27), or by secondary healing (n=5), skin graft (n=2), local fasciocutaneous (n=1), or free vascularised muscle flap (n=1). Systemic antibiotics according to cultures were administered for 5–7 days. Generalized Charcot osteomyelitis was an indication for amputation. Mean hospital stay was 13.8 days (range 1–34) and 2.7 (range 1–7) surgical procedures per patient were recorded. Infection control was achieved in 26 cases (72.2%), whereas amputations were performed in 10 cases (27.8%). Below-knee amputation was undertaken in 4 host-type C patients with Charcot osteomyelitis of the foot. Ray amputations were performed in 4 diabetic feet. Six amputees were classified as host-C and 3 as host-B. One host-type A patient with recurrent post-traumatic toe osteomyelitis, underwent a distal phalanx amputation as definitive solution. Amputation rates were 55% among host-C, 22% among host-B and 9% among host-A patients (p<
0.001). Diffuse foot osteomyelitis in systemically compromised patients resulted in high amputation rates. Better results were obtained in non-compromised hosts and focal osteomyelitis.
Flaps constitute an integral part of the treatment of soft tissue and skeletal infections of the extremities, focusing on the coverage and augmentation of the local biology. In a 6-year period, a total of 33 septic defects of the upper (6) and lower (27) extremities were treated with 4 free and 29 pedicled flaps, after extensive surgical debridement of the septic site. In the lower extremity, treatment included 3 free (2 latissimus dorsi and 1 serratus anterior), and 24 pedicled flaps (5 heads of gastrocnemius, 7 soleus, 1 abductor hallucis, 9 reverse fasciocutaneous, 1 combined medial head of gastrocnemius and soleus and 1 extensor longus hallucis) for 3 cases of soft tissue sepsis and 24 septic defects of the skeleton. In the upper extremity, 1 free vascularised fibular graft (combined with muscle-skin) and 5 pedicled flaps (2 homodigital, 1 heterodigital, 1 cross-finger, 1 periosteal) were used for 3 soft tissue and 3 skeletal septic defects. All but one flaps of the lower extremities were covered with split thickness skin (simultaneously or within 7 days), whereas flaps of the upper extremity included skin in all cases. Three flaps (2 reverse fasciocutaneous and one soleus) were revised (with latissimus dorsi, serratus anterior and extensor longus hallucis flaps respectively) in a mean period of 4 months due to persistent infection and 4 skin grafts were revised due to superficial infection. In a minimum follow-up period of 9 months (9–60 months) full coverage of the defect and treatment of infection was accomplished in all patients, resulting in a good functional and aesthetic outcome. Except for 2 patients, all were able to walk and use their extremity and returned to previous activities. The use of flaps in the treatment of septic skeletal or soft tissue defects leads to a functional upper or lower extremity and successfully prevents amputation.
Type of study: double randomised prospective, comparison of 2 different procedures.