BIOACTIVE GLASS S53P4: a new opportunity for the treatment in the diabetic foot osteomyelitis

Bioactive Glass in a Multi Drug Resistance Osteomyelitis in Diabetic Foot: Case Report

Diabetic foot osteomyelitis (DFO) is a clinical problem with high risk of amputation. The treatment of DFO is still an unsolved challenge. Surgical therapy, antibiotic therapy or conservative treatment are still debated for the timing and the consequences. Long antibiotic therapies expose the selection of multidrug-resistant bacteria. Nowadays the use of new bone substitutes aims to support the load of the bone segments and to ensure the eradication of the infectious process after surgical treatment. A case report of digital osteomyelitis due to a multidrug resistant bacteria was treated with a conservative treatment and use of bioglass (Bonalive) that has the ability to inhibit bacterial growth. A long follow-up shows the resolution of infectious process, no ulcer recurrence and persistent recovery of its ability to walk. Our results agree with literature data and suggest that bioglass may be considered a useful option to manage DFO and achieve healing with a very conservative approach.

Bioactive glass, a new tool for the treatment in the diabetic foot recalcitrant osteomyelitis: A case series with 24-month follow-up

BACKGROUND

The bioactive glass (BAG) is a promising solution for the reconstruction of bone defects and the eradication of infection in patients with osteomyelitis, however references to the treatment of diabetic foot osteomyelitis are scarce in the literature.

METHODS

Our experience in patients with diabetic foot osteomyelitis, who required surgical debridement and void filling, in which we use bioactive glass (n = 6), was evaluated. During a minimum follow-up of 24 months, the presence of persistent infection and healing rate, post-surgical complications, surgical reinterventions, degree of osseointegration and BAG-related side effects was analyzed.

RESULTS

At the end of the follow-up, none of the patients showed signs of persistent infection and the healing rate was 66.6% (4/6). Postoperative complications were noted in 3 patients and two of the them required new surgical intervention, both due to skin coverage or vascular complications. A complete osseointegration in the 66.6% of the patients and no cases of local adverse effects were recorded.

CONCLUSIONS

The bioactive glass can be a useful tool in the treatment of certain cases of diabetic foot osteomyelitis, provided that a multidisciplinary approach and strict patient selection is in place.

LEVEL OF EVIDENCE

IV.

Possible Advantages of S53P4 Bioactive Glass in the Treatment of Septic Osteoarthritis of the First Metatarsophalangeal Joint in the Diabetic Foot

Biomechanically, the great toe with its metatarsophalangeal (MTP) joint plays a key role in standing and walking, making the first MTP joint one of the main predilection sites for ulcer formation, and consequently for bone and joint infection and even amputation. If conservative treatment fails, the main goal of surgery is to remove all infected tissue and preserve the first ray. To improve surgical outcomes, development of new biomaterials like Bioactive Glass S53P4 has begun. Bioactive Glass is useful because of its antibacterial properties; furthermore, its osteostimulative and osteoconductive qualities make the bone substitute particularly suitable as a bone defect filler for the treatment of osteomyelitis. The aim of our retrospective observational study was to compare the outcomes following ulcerectomy with segmental resection of the infected joint and bone and temporary stabilization with an external fixator, both with and without added Bioactive Glass. A comparison of added Bioactive Glass with the traditional surgical treatment in septic osteoarthritis of the first MTP joint showed Bioactive Glass to be effective. During a one-year follow-up, patients with Bioactive Glass required no additional antibiotic therapy or surgical intervention. Bioactive Glass, when applied to the diabetic foot, showed itself to be a safe bone substitute biomaterial.

Pilot Experience on the Use of S54P4 Bioactive Glass in the Surgical Management of Diabetic Foot Osteomyelitis

To test safety and efficacy of bioactive glass, a novel material used to replace bone, able to completely bond itself to the host tissues on patients treated for osteomyelitis (OM) complicating a diabetic foot (DF). We evaluated a group of patients consecutively admitted in our department between September and December 2018, who underwent surgical DF procedures for OM and in whom the use of bioactive glass could limit the demolition phase of surgical procedure. Patients were treated with bioactive glass S53P4 on top of standard treatment directly in operating room. The patients were weekly controlled for 6 months or until complete healing. During follow-up, we analyzed primarily healing rate and secondarily time of healing, need for further debridement procedures, recurrences, and adverse or hypersensitivity reactions to study treatment. Ten DF patients were enrolled (male/female 6/4; mean age 56 ± 11 years; mean duration of diabetes 10.5 ± 4.7 years, mean hemoglobin A1c 7.2 ± 0.9%). Patients underwent surgical procedure during which, after an accurate debridement, bioactive glass was applied. A healing rate of 80% in a mean time of 34 ± 2 days, with only 1 patient who needed a second surgical look, was observed. Neither recurrences nor adverse events during follow-up were observed in treated patients. This pilot experience demonstrated that bioactive glass can be considered a useful tool for the surgical treatment of DF-related OM.

Antimicrobial activity of bioactive glass S53P4 against representative microorganisms causing osteomyelitis - Real-time assessment by isothermal microcalorimetry

Bioactive glass (BAG) is a synthetic bone substitute with intrinsic antimicrobial properties, used for bone defect filling. We evaluated the antimicrobial activity of two formulations of BAG S53P4 against representative pathogens of osteomyelitis: Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli and Candida albicans. Antimicrobial activity of BAG S53P4 was assessed by isothermal microcalorimetry, a highly sensitive assay measuring metabolic-related microbial heat production in real-time. Standard CFUs-counting was performed in parallel. BAG granules (diameter 500-800 μm) and powder (<45 μm) were evaluated in two concentrations (400 and 800 mg/ml). Isothermal microcalorimetry was performed in glass ampoules containing growth medium, BAG and test microorganism, heat production was measured for 24 h. BAG S53P4 inhibited heat production of most-tested microorganisms with heat reduction of 60%-98% compared to positive control after 24 h of exposure to the highest-tested concentration (800 mg/ml). BAG S53P4 in powder formulation (<45 μm) inhibited more microbial growth than in granule formulation (500-800 μm), with the exception of C. albicans for which both formulations presented similar inhibition rates ranging between 87 % and 97 %. The BAG inhibitory ratios estimated from the variation in the growth rate constants of each microorganism compared to the growth control ranged between 2.55 % and 100 %. Comparable results were obtained by CFUs-counting, with complete reduction in cell viability of most microorganisms after ≤ 24 h of microbial exposure to BAG S53P4 powder. In summary, BAG S53P4 demonstrated efficient inhibition of microbial growth, especially in powder formulation.

The role of bioactive glass in the management of chronic osteomyelitis: a systematic review of literature and current evidence

Background: The increase of orthopaedic surgical interventions has given rise to an increased prevalence of chronic osteomyelitis. The principles of management of chronic osteomyelitis are well defined and include a thorough debridement, dead space management followed by an adequate period of appropriate antibiotics. Bioactive glass has garnered interest in recent years as a potential void filler following debridement. In the present systematic review, we explore the role of bioactive glass as a dead space management agent following debridement of chronic osteomyelitis.Methods: A search was made for all the articles pertaining to the role of bioactive glass in chronic osteomyelitis. The keywords used for search in PUBMED/MEDLINE were 'Bioactive glass' and 'chronic osteomyelitis'. A total of nine publications evaluating the outcome of 206 patients were included for evaluation.Results: The overall cure rate was 86% with 24 patients (11.6%) experiencing recurrence, while five patients were lost to follow-up. Out of the total 24 recurrences or persistent infections, 10 were associated with poor post-operative wound healing which progressed to recurrence.Conclusions: Bioactive glass appears to provide an attractive alternative for bone void filling after debridement of chronic osteomyelitis with good long-term outcomes. Potential advantages include a unique mechanism of anti-microbial action rendering it active against multi-drug resistant bacteria, use as a single stage procedure and gradual replacement by bone.