Selected publications

January 2023

In manuscript

Hydroxyapatite an Antibiotic Recruiting Moiety for Local Treatment of Bone Infections

Radical debridement and dead space management with an antibiotic containing calcium sulphate/ hydroxyapatite (CaS/HA) bone substitute has shown excellent long-term outcomes in chronic osteomyelitis. However, sessile bacteria have been shown to remain in the adjacent cortical bone canaliculi or soft tissue, which may repopulate the site causing a relapse of the infection. Herein, we propose a method in which systemically administered antibiotics seek and bind locally implanted HA material thereby protecting the biomaterial and the surrounding tissue from bacterial repopulation. The primary aim of this study was to evaluate if systemically given tetracycline (TET) could biomodulate locally implanted HA particles and impart an anti-bacterial effect on the material. Furthermore, the time kinetics of HA-TET binding and effect of protein and drug passivation of HA on TET binding was studied. The binding of TET to Nano(n)- and micro (m)-sized HA particles was rapid and plateaued already at 1 h.  Since protein passivation of HA after in-vivo implantation could affect HA-TET interaction, we investigated the effect of fetal bovine serum exposure on HA-TET binding in an antibacterial assay. Although, serum exposure reduced the zone of inhibition (ZOI) of S Aureus for both nano and micro-HA, a significant ZOI could still be observed after pre-incubation of HA with serum, indicating that protein passivation does not completely inhibit TET-HA binding. On the contrary, we could show that zoledronic acid (ZA) competes for the same binding sites as TET and exposure to high dose ZA led to complete reduction in TET-HA binding. In an in-vivo setting, we then confirm that systemically administered TET seeks HA particles implanted in a muscle pouch and a subcutaneous pouch in rats and mice respectively and the HA particles are protected from S. Aureus infection. This study therefore describes a new drug delivery method for local treatment of bone infections, a method which may further reduce infection recurrences.

January 2023

Journal of Bone and Joint Infection

Systemic rifampicin shows accretion to locally implanted hydroxyapatite particles in a rat abdominal muscle pouch model 

Introduction:biomaterials combined with antibiotics are routinely used for the management of bone infections. After eluting high concentrations of antibiotics during the first week, sub-inhibitory concentrations of antibiotics may lead to late repopulation of recalcitrant bacteria. Recent studies have shown that systemically given antibiotics like tetracycline and rifampicin (RIF) could seek and bind to locally implanted hydroxyapatite (HA). The aim of this in vivo study was to test if systemically administered rifampicin could replenish HA-based biomaterials with or without prior antibiotic loading to protect the material from late bacterial repopulation. Methods: in vivo accretion of systemically administered RIF to three different types of HA-based materials was tested. In group 1, nano (n)- and micro (m)-sized HA particles were used, while group 2 consisted of a calcium sulfate/hydroxyapatite (CaS/HA) biomaterial without preloaded antibiotics gentamycin (GEN) or vancomycin (VAN), and in group 3, the CaS/HA material contained GEN (CaS/HA+GEN) or VAN (CaS/HA+VAN). The above materials were implanted in an abdominal muscle pouch model in rats, and at 7 d post-surgery, the animals were assigned to a control group (i.e., no systemic antibiotic) and a test group (i.e., animals receiving one single intraperitoneal injection of RIF each day (4 mg per rat) for 3 consecutive days). Twenty-four hours after the third injection, the animals were sacrificed and the implanted pellets were retrieved and tested against Staphylococcus aureus ATCC 25923 in an agar diffusion assay. After overnight incubation, the zone of inhibition (ZOI) around the pellets were measured. Results: in the control group, 2/6 CaS/HA+GEN pellets had a ZOI, while all other harvested pellets had no ZOI. No pellets from animals in test group 1 had a ZOI. In test group 2, 10/10 CaS/HA pellets showed a ZOI. In test group 3, 5/6 CaS/HA+GEN and 4/6 CaS/HA+VAN pellets showed a ZOI. Conclusions: in this proof-of-concept study, we have shown that a locally implanted biphasic CaS/HA carrier after 1 week can be loaded by systemic RIF administration and exert an antibacterial effect. Further in vivo infection models are necessary to validate our findings.

December 2022

Frontiers in Bioengineering and Biotechnology

Longitudinal in vivo biodistribution of nano and micro sized hydroxyapatite particles implanted in a bone defect

Hydroxyapatite (HA) has been widely used as a bone substitute and more recently as a carrier for local delivery of bone targeted drugs. Majority of the approved HA based biomaterials and drug carriers comprise of micrometer sized particulate HA (mHA) or granules and can therefore only be used for extracellular drug release. This shortcoming could be overcome with the use of cell penetrating HA nanoparticles (nHA) but a major concern with the clinical use of nHA is the lack of data on its in vivo biodistribution after implantation. In this study, we aimed to study the in vivo biodistribution of locally implanted nHA in a clinically relevant tibial void in rats and compare it with mHA or a combination of mHA and nHA. To enable in vivo tracking, HA particles were first labelled with 14C-zoledronic acid (14C-ZA), known to have a high binding affinity to HA. The labelled particles were then implanted in the animals and the radioactivity in the proximal tibia and vital organs was detected at various time points (Day 1, 7 and 28) post-implantation using scintillation counting. The local distribution of the particles in the bone was studied with micro-CT. We found that majority (>99.9%) of the implanted HA particles, irrespective of the size, stayed locally at the implantation site even after 28 days and the findings were confirmed using micro-CT. Less than 0.1% radioactivity was observed in the kidney and the spleen at later time points of day 7 and 28. No pathological changes in any of the vital organs could be observed histologically. This is the first longitudinal in vivo HA biodistribution study showing that the local implantation of nHA particles in bone is safe and that nHA could potentially be used for localized drug delivery.

November 2022

Bone Joint Research

Extended Local Release and Improved Bacterial Eradication by Adding Rifampicin to a Biphasic Ceramic Carrier Containing Gentamicin or Vancomycin

Aim

There is a lack of biomaterial-based carriers for the local delivery of rifampicin (RIF), one of the cornerstone second defence antibiotics for bone infections. RIF is also known for causing rapid development of antibiotic resistance when given as monotherapy. This in vitro study evaluated a clinically used biphasic calcium sulphate/hydroxyapatite (CaS/HA) biomaterial as a carrier for dual delivery of RIF with vancomycin (VAN) or gentamicin (GEN).

Methods

The CaS/HA composites containing RIF/GEN/VAN, either alone or in combination, were first prepared and their injectability, setting time, and antibiotic elution profiles were assessed. Using a continuous disk diffusion assay, the antibacterial behaviour of the material was tested on both planktonic and biofilm-embedded forms of standard and clinical strains of Staphylococcus aureus for 28 days. Development of bacterial resistance to RIF was determined by exposing the biofilm-embedded bacteria continuously to released fractions of antibiotics from CaS/HA-antibiotic composites.

Results

Following the addition of RIF to CaS/HA-VAN/GEN, adequate injectability and setting of the CaS/HA composites were noted. Sustained release of RIF above the minimum inhibitory concentrations of S. aureus was observed until study endpoint (day 35). Only combinations of CaS/HA-VAN/GEN + RIF exhibited antibacterial and antibiofilm effects yielding no viable bacteria at study endpoint. The S. aureus strains developed resistance to RIF when biofilms were subjected to CaS/HA-RIF alone but not with CaS/HA-VAN/GEN + RIF.

Conclusion

Our in vitro results indicate that biphasic CaS/HA loaded with VAN or GEN could be used as a carrier for RIF for local delivery in clinically demanding bone infections.

June 2022

Frontiers in Cellular and Infection Microbiology

The Effectiveness of Metagenomic Next-Generation Sequencing in the Diagnosis of Prosthetic Joint Infection: A Systematic Review and Meta-Analysis

Background: A prosthetic joint infection (PJI) is a devastating complication following total joint arthroplasties with poor prognosis. Identifying an accurate and prompt diagnostic method is particularly important for PJI. Recently, the diagnostic value of metagenomic next-generation sequencing (mNGS) in detecting PJI has attracted much attention, while the evidence of its accuracy is quite limited. Thus, this study aimed to evaluate the accuracy of mNGS for the diagnosis of PJI.

Methods: We summarized published studies to identify the potential diagnostic value of mNGS for PJI patients by searching online databases using keywords such as “prosthetic joint infection”, “PJI”, and “metagenomic sequencing”. Ten of 380 studies with 955 patients in total were included. The included studies provided sufficient data for the completion of 2-by-2 tables. We calculated the sensitivity, specificity, and area under the SROC curve (AUC) to evaluate mNGS for PJI diagnosis.

Results: We found that the pooled diagnostic sensitivity and specificity of mNGS for PJI were 0.93 (95% CI, 0.83 to 0.97) and 0.95 (95% CI, 0.92 to 0.97), respectively. Positive and negative likelihood ratios were 18.3 (95% CI, 10.9 to 30.6) and 0.07 (95% CI, 0.03 to 0.18), respectively. The area under the curve was 0.96 (95% CI, 0.93 to 0.97).

Conclusion: Metagenomic next-generation sequencing displays high accuracy in the diagnosis of PJI, especially for culture-negative cases

September 2021

BMC Musculoskeletal Discorders

Different microbial and resistance patterns in primary total knee arthroplasty infections – a report on 283 patients from Lithuania and Sweden

Background

The microbiology and the susceptibility patterns of infected total knee arthroplasties (TKAs) vary depending on demographic, local antimicrobial stewardship, and surgical factors. We wanted to compare the recent microbial profile and antimicrobial resistance pattern in revisions due to infections after primary TKAs in Sweden and Lithuania. Our hypothesis was that there is a difference in bacteriology and resistance pattern based on patient related, societal and local hospital factors as almost similar praxis have been applied for TKA surgery, short term systemic prophylaxis and routine use of local gentamicin containing bone cement.

Methods

Primary TKAs revised for the first time due to verified or suspected infection were collected nationwide in Sweden during 2018, and in Lithuania between 2011 and 2020 from a single major TKA revision centre in Kaunas. We identified 202 TKAs in Sweden from the Swedish Knee Arthroplasty Register and 84 from Kaunas revised due to infection. We collected available culture reports and evaluated the type of microorganisms with antimicrobial resistance pattern at revision.

Results

The majority of the infected cases in Sweden were early-type prosthetic joint infection (PJI) (44%), whereas late-type PJI (52%) were more common in the Kaunas cases. Gram-positive bacteria prevailed in both Sweden (55%) and Lithuania (80%). Staphylococcus aureus was the most frequent organism identified in both countries (33% in Sweden and 34% in Lithuania). More polymicrobial infections were observed in Sweden than in Lithuania (16 and 6% respectively). Methicillin resistance in Staphylococcus aureus and coagulase-negative staphylococci were higher in Lithuania (4/28 and 19/29) than in Sweden (1/42 and 9/41).

Conclusions

The type of infections, microbial profile, and drug resistance pattern differed between Sweden and Lithuania. Societal and local hospitals factors with emerging resistance in Lithuania are the most plausible explanation for the difference. Lack of complete data on a national level in Lithuania underlines the importance of adding microbiology of PJIs in implant registers for national aggregation and allow cross country comparisons.

September 2020

EORS 2020

Injectability of a ceramic bone substitute mixed with rifampicin for local delivery.

BACKGROUND

With promising antibiofilm properties, rifampicin is considered as a cornerstone in the complementary treatment of bone and joint infections. But, achieving an adequate concentration of rifampicin long-term in bone tissue is a challenge. Long-term systemic administration also comes with concomitant side effects. Thus, local delivery of rifampicin in a carrier to ensure the high local concentration of antibiotic in surgical site after intervention due to infection could be a valuable alternative. However, an ideal platform for local delivery of rifampicin is still lacking. A calcium sulphate/hydroxyapatite (CaS/HA) (Cerament, Bonesupport AB, Sweden) biomaterial was used as a local delivery platform. Here we aimed 1) to evaluate the injectability of CaS/HA hand-mixed with rifampicin at various concentrations up to maximum one daily dose used systemically in clinical practice 2) to test a clinically used and commercially available mixing device containing the biphasic ceramic with rifampicin

August 2020

Scientific Reports

A biphasic nano hydroxyapatite/calcium sulphate carrier containing Rifampicin and Isoniazid for local delivery gives sustained and effective antibiotic release and prevents biofilm formation

Long term multiple systemic antibiotics form the cornerstone in the treatment of bone and joint tuberculosis, often combined with local surgical eradication. Implanted carriers for local drug delivery have recently been introduced to overcome some of the limitations associated with conventional treatment strategies. In this study, we used a calcium sulphate hemihydrate (CSH)/nanohydroxyapatite (nHAP) based nanocement (NC) biomaterial as a void filler as well as a local delivery carrier of two standard of care tuberculosis drugs, Rifampicin (RFP) and Isoniazid (INH). We observed that the antibiotics showed different release patterns where INH showed a burst release of 67% and 100% release alone and in combination within one week, respectively whereas RFP showed sustained release of 42% and 49% release alone and in combination over a period of 12 weeks, respectively indicating different possible interactions of antibiotics with nHAP. The interactions were studied using computational methodology, which showed that the binding energy of nHAP with RFP was 148 kcal/mol and INH was 11 kcal/mol, thus varying substantially resulting in RFP being retained in the nHAP matrix. Our findings suggest that a biphasic ceramic based drug delivery system could be a promising treatment alternative to bone and joint TB.

May 2020

Journal of Orthopaedic Translation

Antibiotic containing bone cement in prevention of hip and knee prosthetic joint infections: A systematic review and meta-analysis

Background: Prosthetic joint infection (PJI) is the most serious total joint arthroplasty (TJA) complication despite several aseptic and antiseptic preventive measures. There is no clear evidence or even consensus, whether antibiotic-loaded bone cement (ALBC) should be used, in addition to systemic short-term routine antibiotic prophylaxis, to reduce the risk of PJI in primary TJA. We aimed to analyze the efficacy of ALBC for prevention of PJI in patients undergoing primary TJA.

Methods: We searched systematically for randomized controlled trials (RCTs) in PubMed, Scopus, Embase, Web of Science and Cochrane library. Two reviewers independently screened potentially eligible studies according to predefined selection criteria and assessed the risk of bias using a modified version of the Cochrane risk of bias tool. PJI was prespecified as the primary outcome of interest. The meta-analyses were based on risk ratios using random-effects model per default. For the purpose of sensitivity, the corresponding fixed effects model odds ratios were calculated with the use of the Peto method as well. To evaluate a potential difference in effect sizes using different types (subgroups) of antibiotics used in bone cement, and at different follow-up periods, we performed stratified meta-analyses.

Results: Thirty-seven studies were eligible for the systematic review and qualitative synthesis, and 9 trials (6507 total joint arthroplasties) were included in this meta-analysis. Overall ALBC significantly reduced the risk of PJI following primary TJAs (RRs, 0.36; 95% CIs, 0.16 to 0.80; P = 0.01) with a moderate degree of inconsistency (I2 = 47%). Based on stratified meta-analyses the use of gentamicin appeared to have a better effect (P = 0.0005) in the total hip arthroplasty. Pooled data of different antibiotics used in knee arthroplasties showed a significant association of cefuroxime (RRs, 0.08; 95% CIs, 0.01 to 0.63; P = 0.02). Further, ALBCs significantly reduced the PJI at one and two years of follow-up (P = 0.03 and P = 0.005 respectively).

Conclusions: The evidence suggests that ALBCs are effective in reducing the PJI following primary TJA; i.e. between 20 and 84% reduced risk. However, the clear limitations of the available trial evidence highlight the need for joint-specific confirmatory trials, that will need to be designed as cluster-randomized trials of clinics in countries with well-functioning arthroplasty registries.The translational potential of this article: This meta-analysis highlights the prophylactic potential of ALBCs in lowering the risk of infection following primary hip or knee arthroplasties but emphasizes the need for more recent confirmatory trials.

January 2020

Journal of Orthopaedic Research
CSA-90 reduces periprosthetic joint infection in a novel rat model challenged with local and systemic Staphylococcus aureus

Infection of orthopedic implants is a growing clinical challenge to manage due to the proliferation of drug-resistant bacterial strains. In this study, we aimed to investigate whether the treatment of implants with ceragenin-90 (CSA-90), a synthetic compound based on endogenous antibacterial peptides, could prevent infection in a novel rat model of periprosthetic joint infection (PJ) challenged with either local or systemic Staphylo-
coccus aureus. A novel preclinical model of PJ was created using press-fit porous titanium implants in the distal femur of male Wistar rats. Sterile implants were pretreated with
500 mg CSA-90 in saline. S. aureus was applied either directly at the time of surgery or administered via tail vein injection immediately afterward. Animals were monitored daily
for clinical and radiographic evidence of infection for a total of 6 weeks. Post-study microbiological, radiographic, and histological analysis were performed to determine the
incidence of PJ and assess osseointegration. CSA-90 treated groups demonstrated a reduced rate of PJ as confirmed by deep tissue swab culture at the time of cull compared
with untreated groups with both local (33% vs 100%; P=.009) and systemic (10% vs 90%; P< .0001) S. aureus inoculation. Median survival time also increased from 8 to 17 days and from 8 to 42 days, respectively. In conclusion, this study describes a novel preclinical model of local and hematogenous PJ using a porous metal implant. CSA-90
reduced the incidence of PJ in this model supporting its further development as an antimicrobial coating for orthopedic implants.

November 2019

Acta Orthopaedica

Synthetic hydroxyapatite: a recruiting platform for biologically active molecules

Background and purpose — Targeted delivery of drugs is important to achieve efficient local concentrations and reduce systemic side effects. We hypothesized that locally implanted synthetic hydroxyapatite (HA) particles can act as a recruiting moiety for systemically administered drugs, leading to targeted drug accretion.

Methods — Synthetic HA particles were implanted ectopically in a muscle pouch in rats, and the binding of systemically circulating drugs such as zoledronic acid (ZA), tetracycline and 18F-fluoride (18F) was studied. The local biological effect was verified in an implant integration model in rats, wherein a hollow implant was filled with synthetic HA particles and the animals were given systemic ZA, 2-weeks post-implantation. The effect of HA particle size on drug binding and the possibility of reloading HA particles were also evaluated in the muscle pouch.

Results — The systemically administered biomolecules (ZA, tetracycline and 18F) all sought the HA moiety placed in the muscle pouch. Statistically significant higher peri-implant bone volume and peak force were observed in the implant containing HA particles compared with the empty implant. After a single injection of ZA at 2 weeks, micro HA particles showed a tendency to accumulate more 14C-zoledronic acid (14C-ZA) than nano-HA particles in the muscle pouch. HA particles could be reloaded when ZA was given again at 4 weeks, showing increased 14C-ZA accretion by 73% in microparticles and 77% in nanoparticles.

Interpretation — We describe a novel method of systemic drug loading resulting in targeted accretion in locally implanted particulate HA, thereby biologically activating the material.

November 2019

Journal of Bone and Joint Infection

Collaboration between orthopaedic surgeons and infection specialists in bone and joint infections

Introduction

In spite of the implementation of certain aseptic procedures in joint prosthetic surgery with so-called clean room air and special body exhaust gowns, as well as the use of multiple antiseptic measures such as preoperative decontamination and antibiotic prophylaxis, orthopaedic infections are still common. Infections caused by work-related or traffic injuries, as well as by blood-borne infections, are demanding, both diagnostically and in terms of treatment. The societal burden is also significant. Data from the Swedish Social Insurance Agency during a 6-year period starting in 1975 reported 1900 orthopaedic infections in Sweden, a country of 8.5 million inhabitants.

For more than 15 years, orthopaedic and infection clinics in Lund, Sweden, have collaborated. Since 1974, this collaboration has become more structuredandsystematic.Atotalof132patientswith orthopaedic complications were treated in the infection clinic in 1980, which corresponds to 14.3% of the infection clinic’s capacity, with an average occupation of nine ward beds.

Half of the more difficult orthopaedic cases were admitted to one particular ward, where the staff received additional training on how to care for postoperative patients.

February 2019

Bone & Joint Research
Vancomycin elution from a biphasic ceramic bone substitute

Objectives: The aim of this study was to analyze drain fluid, blood, and urine simultaneously to follow the long-term release of vancomycin from a biphasic ceramic carrier in major hip surgery. our hypothesis was that there would be high local vancomycin concentrations during the first week with safe low systemic trough levels and a complete antibiotic release during the first month.

Methods: Nine patients (six female, three male; mean age 75.3 years (sd 12.3; 44 to 84)) with tro- chanteric hip fractures had internal fixations. An injectable ceramic bone substitute, with hydroxyapatite in a calcium sulphate matrix, containing 66 mg of vancomycin per millilitre, was inserted to augment the fixation. The vancomycin elution was followed by simultane- ously collecting drain fluid, blood, and urine.

Results: The antibiotic concentration in the drain reached a peak during the first six hours post- surgery (mean 966.1 mg/l), which decreased linearly to a mean value of 88.3 mg/l at 2.5 days. In the urine, the vancomycin concentration reached 99.8 mg/l during the first two days, followed by a logarithmic decrease over the next two weeks to reach 0 mg/l at 20 days. The systemic concentration of vancomycin measured in blood serum was low and decreased linearly from 2.17 mg/l at one hour post-surgery to 0 mg/l at four days postoperatively.

Conclusion: This is the first long-term pharmacokinetic study that reports vancomycin release from a biphasic injectable ceramic bone substitute. The study shows initial high targeted local van- comycin levels, sustained and complete release at three weeks, and systemic concentrations well below toxic levels. The plain ceramic bone substitute has been proven to regenerate bone but should also be useful in preventing bone infection.

  1. Sebastian S., et al., Hydroxyapatite an Antibiotic Recruiting Moiety for Local Treatment of Bone Infections (in manuscript)
  2. Sebastian S., et al., Systemic rifampicin shows accretion to locally implanted hydroxyapatite particles in a rat abdominal muscle pouch model Journal of Bone and Joint Infection 2023
  3. Liu Y., et al., Longitudinal in vivo biodistribution of nano and micro sized hydroxyapatite particles implanted in a bone defect Frontiers in Bioengineering and Biotechnology 2022
  4. Sebastian S., et al., Extended local release and improved bacterial eradication by adding rifampicin to a biphasic ceramic carrier containing gentamicin or vancomycin Bone Joint Research 2022
  5. Jun Tan, Yang Liu., et al., The effectiveness of metagenomic next-generation sequencing in the diagnosis of prosthetic joint infection: A systematic review and meta-analysis Frontiers inCellular and Infection Microbiology, 2022
  6. Sebastian, S., et al., Different microbial and resistance patterns in primary total knee arthroplasty infections–a report on 283 patients from Lithuania and Sweden BMC Musculoskeletal Disorders, 2021
  7. Sebastian, S., et al., Injectability of a ceramic bone substitute mixed with rifampicin for local delivery.28thAnnual meeting of European Orthopedic Research Society (EORS 2020). Izmir, Turkey, September 17th-18th, 2020. Abstract number 194.
  8. Qayoom, I., et al., A biphasic nanohydroxyapatite/calcium sulphate carrier containing Rifampicin and Isoniazid for local delivery gives sustained and effective antibiotic release and prevents biofilm formation. Scientific Reports, 2020. 10(1): p. 14128.
  9. Sebastian S., et al., Antibiotic containing bone cement in prevention of hip and knee prosthetic joint infections: A systematic review and meta-analysis Journal of Orthopaedic Translation 2020
  10. Mills, R.J., et al., CSA-90 reduces periprosthetic joint infection in a novel rat model challenged with local and systemic Staphylococcus aureus. Journal of Orthopaedic Research, 2020. 38(9): p. 2065-2073.
  11. Raina D., et al., Synthetic hydroxyapatite: a recruiting platform for biologically active molecules Acta Orthopaedica, 2019
  12. SÅ Hedström, Lars Lidgren Collaboration between orthopaedic surgeons and infection specialists in bone and joint infections Journal of Bone and Joint Infection 2019
  13. Stravinskas, M., et al., Vancomycin elution from a biphasic ceramic bone substitute. Bone & Joint Research, 2019. 8(2): p. 49-54.
  14. TW Bauer., et al., Hip and Knee Section, Diagnosis, Laboratory Tests: Proceedings of International Consensus on Orthopedic Infections The Journal of Arthroplasty 2019.
  15. P Chen., et al., Fabrication of a silver nanoparticle-coated collagen membrane with anti-bacterial and anti-inflammatory activities for guided bone regeneration Biomedical Materials 2018.
  16. Stravinskas, M., et al., A ceramic bone substitute containing gentamicin gives good outcome in trochanteric hip fractures treated with dynamic hip screw and in revision of total hip arthroplasty: a case series.BMC Musculoskeletal Disorders, 2018. 19(1): p. 438.
  17. Stravinskas, M., et al., Antibiotic Containing Bone Substitute in Major Hip Surgery: A Long-Term Gentamicin Elution Study. Journal of Bone & Joint Infection, 2018. 3(2): p. 68-72.
  18. Stravinskas, M., et al., Pharmacokinetics of gentamicin eluted from a regenerating bone graft substitute: In vitro and clinical release studies.Bone & joint research, 2016. 5(9): p. 427-435.
  19. Raina, D., et al., A biphasic bone substitute with gentamycin regenerates bone in osteomyelitis with muscle acting as an osteoinductive niche.Orthopaedic proceedings, 2015. 97-B(SUPP_16): p. 24-24.
  20. LT Nilsson., et al., Deep infection following femoral neck fracture osteosynthesis Orthopédie Traumatologie 1993.
  21. Sten Bengtson., et al., Cost analysis of prophylaxis with antibiotics to prevent infected knee arthroplasty. BMJ: British Medical Journal 1989.
  22. SÅ Hedström., et al., Cefuroxime prophylaxis in trochanteric hip fracture operations Acta Orthopaedica Scandinavica 1987.
  23. L Lidgren., et al., Post-Operative Wound Infections in Clean Orthopaedic Surgery:Review of a 5-year material  Acta Orthopaedica Scandinavica 1974.
  24. Ericson C., et al., Cloxacillin in the prophylaxis of postoperative infections of the hip The Journal of Bone & Joint Surgery 55(4):p 808-843, June 1973.

Additional references related to bone and joint infection can be found here.