Objectives. This study was conducted to evaluate the cytokine-release kinetics of platelet-rich plasma (PRP) according to different activation protocols. Methods. Two manual preparation procedures (single-spin (SS) at 900 g for five minutes; double-spin (DS) at 900 g for five minutes and then 1500 g for 15 minutes) were performed for each of 14 healthy subjects. Both preparations were tested for platelet activation by one of three activation protocols: no activation, activation with calcium (Ca) only, or calcium with a low dose (50 IU per 1 ml PRP) of thrombin. Each preparation was divided into four aliquots and incubated for one hour, 24 hours, 72 hours, and seven days. The cytokine-release kinetics were evaluated by assessing PDGF, TGF, VEGF, FGF, IL-1, and MMP-9 concentrations with bead-based sandwich immunoassay. Results. The concentration of cytokine released from PRP varied over time and was influenced by various activation protocols. Ca-only activation had a significant effect on the DS PRPs (where the VEGF, FGF, and IL-1 concentrations were sustained) while Ca/thrombin activation had effects on both SS and DS PRPs (where the PDGF and VEGF concentrations were sustained and the TGF and FGF concentrations were short). The IL-1 content showed a significant increase with Ca-only or Ca/thrombin activation while these activations did not increase the MMP-9 concentration. Conclusion. The SS and DS methods differed in their effect on cytokine release, and this effect varied among the cytokines analysed. In addition, low dose of thrombin/calcium activation increased the overall cytokine release of the PRP preparations over seven days, relative to that with a calcium-only supplement or non-activation. Cite this article: Professor J. H. Oh. Cytokine-release kinetics of platelet-rich plasma according to various activation protocols. Bone Joint Res 2016;5:37–45. doi: 10.1302/2046-3758.52.2000540

Aims. Aseptic loosening is the most common cause of failure following cemented total knee arthroplasty (TKA), and has been linked to poor cementation technique. We aimed to develop a consensus on the optimal technique for component cementation in TKA. Methods. A UK-based, three-round, online modified Delphi Expert Consensus Study was completed focusing on cementation technique in TKA. Experts were identified as having a minimum of five years’ consultant experience in the NHS and fulfilling any one of the following criteria: a ‘high volume’ knee arthroplasty practice (> 150 TKAs per annum) as identified from the National joint Registry of England, Wales, Northern Ireland and the Isle of Man; a senior author of at least five peer reviewed articles related to TKA in the previous five years; a surgeon who is named trainer for a post-certificate of comletion of training fellowship in TKA. Results. In total, 81 experts (round 1) and 80 experts (round 2 and 3) completed the Delphi Study. Four domains with a total of 24 statements were identified. 100% consensus was reached within the cement preparation, pressurization, and cement curing domains. 90% consensus was reached within the cement application domain. Consensus was not reached with only one statement regarding the handling of cement during initial application to the tibial and/or femoral bone surfaces. Conclusion. The Cementing Techniques In Knee Surgery (CeTIKS) Delphi consensus study presents comprehensive recommendations on the optimal technique for component cementing in TKA. Expert opinion has a place in the hierarchy of evidence and, until better evidence is available these recommendations should be considered when cementing a TKA. Cite this article: Bone Jt Open 2023;4(9):682–688

Aims. Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects. Methods. We performed a retrospective review at a single institution of patients undergoing revision THA by a single surgeon. We identified 49 consecutive patients with large acetabular defects where the biphasic BGS was applied, with no other products added to the BGS. After placement of metallic acetabular implants, the BGS was injected into the remaining bone defects surrounding the new implants. Patients were followed and monitored for functional outcome scores, implant fixation, radiological graft site remodelling, and revision failures. Results. Mean follow-up was 39.5 months (36 to 71), with a significant improvement in post-revision function compared to preoperative function. Graft site remodelling was rated radiologically as moderate in 31 hips (63%) and strong in 12 hips (24%). There were no cases of complete graft site dissolution. No acetabular loosening was identified. None of the patients developed clinically significant heterotopic ossification. There were twelve reoperations: six patients developed post-revision infections, three experienced dislocations, two sustained periprosthetic femur fractures, and one subject had femoral component aseptic loosening. Conclusion. Our series reports bone defect restoration with the sole use of a biphasic injectable BGS in the periacetabular region. We did not observe significant graft dissolution. We emphasize that successful graft site remodelling requires meticulous recipient site preparation. Cite this article: Bone Jt Open 2022;3(12):991–997

During the pandemic of COVID-19, some patients with COVID-19 may need emergency surgeries. As spine surgeons, it is our responsibility to ensure appropriate treatment to the patients with COVID-19 and spinal diseases. A protocol for spinal surgery and related management on patients with COVID-19 has been reviewed. Patient preparation for emergency surgeries, indications, and contraindications of emergency surgeries, operating room preparation, infection control precautions and personal protective equipments (PPE), anesthesia management, intraoperative procedures, postoperative management, medical waste disposal, and surveillance of healthcare workers were reviewed. It should be safe for surgeons with PPE of protection level 2 to perform spinal surgeries on patients with COVID-19. Standardized and careful surgical procedures should be necessary to reduce the exposure to COVID-19

Aims. To characterize the intracellular penetration of osteoblasts and osteoclasts by methicillin-resistant Staphylococcus aureus (MRSA) and the antibiotic and detergent susceptibility of MRSA in bone. Methods. Time-lapse confocal microscopy was used to analyze the interaction of MRSA strain USA300 with primary murine osteoblasts and osteoclasts. The effects of early and delayed antibiotic treatments on intracellular and extracellular bacterial colony formation and cell death were quantified. We tested the effects of cefazolin, gentamicin, vancomycin, tetracycline, rifampicin, and ampicillin, as well as agents used in surgical preparation and irrigation. Results. MRSA infiltrated bone-resident cells within 15 to 30 minutes. Penetration was most effectively prevented with early (i.e. 30 minutes) antibiotic administration. The combined administration of rifampicin with other antibiotics potentiated their protective effects against MRSA-induced cytotoxicity and most significantly reduced extracellular bacterial bioburden. Gentamicin-containing compounds were most effective in reducing intracellular MRSA bioburden. Of the surgical preparation agents evaluated, betadine reduced in vitro MRSA growth to the greatest extent. Conclusion. The standard of care for open fractures involves debridement and antibiotics within the first six hours of injury but does not account for the window in which bacteria penetrate cells. Antibiotics must be administered as early as possible after injury or prior to incision to prevent intracellular infestation. Rifampicin can potentiate the capacity of antibiotic regimens to reduce MRSA-induced cytotoxicity. Cite this article:Bone Joint Res. 2020;9(2):49–59

Aims. Femoral bone preparation using compaction technique has been shown to preserve bone and improve implant fixation in animal models. No long-term clinical outcomes are available. There are no significant long-term differences between compaction and broaching techniques for primary total hip arthroplasty (THA) in terms of migration, clinical, and radiological outcomes. Methods. A total of 28 patients received one-stage bilateral primary THA with cementless femoral stems (56 hips). They were randomized to compaction on one femur and broaching on the contralateral femur. Overall, 13 patients were lost to the ten-year follow-up leaving 30 hips to be evaluated in terms of stem migration (using radiostereometry), radiological changes, Harris Hip Score, Oxford Hip Score, and complications. Results. Over a mean follow-up period of 10.6 years, the mean stem subsidence was similar between groups, with a mean of -1.20 mm (95% confidence interval (CI) -2.28 to -0.12) in the broaching group and a mean of -0.73 mm (95% CI -1.65 to 0.20) in the compaction group (p = 0.07). The long-term migration patterns of all stems were similar. The clinical and radiological outcomes were similar between groups. There were two intraoperative fractures in the compaction group that were fixed with cable wire and healed without complications. No stems were revised. Conclusion. Similar stem subsidence and radiological and clinical outcomes were identified after the use of compaction and broaching techniques of the femur at long-term follow-up. Only the compaction group had intraoperative periprosthetic femur fractures, but there were no long-term consequences of these. Cite this article: Bone Jt Open 2021;2(12):1035–1042

Aims. Arthroplasty has become increasingly popular to treat end-stage ankle arthritis. Iatrogenic posterior neurovascular and tendinous injury have been described from saw cuts. However, it is hypothesized that posterior ankle structures could be damaged by inserting tibial guide pins too deeply and be a potential cause of residual hindfoot pain. Methods. The preparation steps for ankle arthroplasty were performed using the Infinity total ankle system in five right-sided cadaveric ankles. All tibial guide pins were intentionally inserted past the posterior tibial cortex for assessment. All posterior ankles were subsequently dissected, with the primary endpoint being the presence of direct contact between the structure and pin. Results. All pin locations confer a risk of damaging posterior ankle structures, with all posterior ankle structures except the flexor hallucis longus tendon being contacted by at least one pin. Centrally-aligned transcortical pins were more likely to contact posteromedial neurovascular structures. Conclusion. These findings support our hypothesis that tibial guide pins pose a considerable risk of contacting and potentially damaging posterior ankle structures during ankle arthroplasty. This study is the first of its kind to assess this risk in the Infinity total ankle system. Cite this article: Bone Jt Open 2021;2(7):503–508

Aims. Psychoeducative prehabilitation to optimize surgical outcomes is relatively novel in spinal fusion surgery and, like most rehabilitation treatments, they are rarely well specified. Spinal fusion patients experience anxieties perioperatively about pain and immobility, which might prolong hospital length of stay (LOS). The aim of this prospective cohort study was to determine if a Preoperative Spinal Education (POSE) programme, specified using the Rehabilitation Treatment Specification System (RTSS) and designed to normalize expectations and reduce anxieties, was safe and reduced LOS. Methods. POSE was offered to 150 prospective patients over ten months (December 2018 to November 2019) Some chose to attend (Attend-POSE) and some did not attend (DNA-POSE). A third independent retrospective group of 150 patients (mean age 57.9 years (SD 14.8), 50.6% female) received surgery prior to POSE (pre-POSE). POSE consisted of an in-person 60-minute education with accompanying literature, specified using the RTSS as psychoeducative treatment components designed to optimize cognitive/affective representations of thoughts/feelings, and normalize anxieties about surgery and its aftermath. Across-group age, sex, median LOS, perioperative complications, and readmission rates were assessed using appropriate statistical tests. Results. In all, 65 (43%) patients (mean age 57.4 years (SD 18.2), 58.8% female) comprised the Attend-POSE, and 85 (57%) DNA-POSE (mean age 54.9 years (SD 15.8), 65.8% female). There were no significant between-group differences in age, sex, surgery type, complications, or readmission rates. Median LOS was statistically different across Pre-POSE (5 days ((interquartile range (IQR) 3 to 7)), Attend-POSE (3 (2 to 5)), and DNA-POSE (4 (3 to 7)), (p = 0.014). Pairwise comparisons showed statistically significant differences between Pre-POSE and Attend-POSE LOS (p = 0.011), but not between any other group comparison. In the Attend-POSE group, there was significant change toward greater surgical preparation, procedural familiarity, and less anxiety. Conclusion. POSE was associated with a significant reduction in LOS for patients undergoing spinal fusion surgery. Patients reported being better prepared for, more familiar, and less anxious about their surgery. POSE did not affect complication or readmission rates, meaning its inclusion was safe. However, uptake (43%) was disappointing and future work should explore potential barriers and challenges to attending POSE. Cite this article: Bone Jt Open 2022;3(2):135–144

Cell therapies hold significant promise for the treatment of injured or diseased musculoskeletal tissues. However, despite advances in research, there is growing concern about the increasing number of clinical centres around the world that are making unwarranted claims or are performing risky biological procedures. Such providers have been known to recommend, prescribe, or deliver so called ‘stem cell’ preparations without sufficient data to support their true content and efficacy. In this annotation, we outline the current environment of stem cell-based treatments and the strategies of marketing directly to consumers. We also outline the difficulties in the regulation of these clinics and make recommendations for best practice and the identification and reporting of illegitimate providers. Cite this article: Bone Joint J 2020;102-B(2):148–154

Aims. The coronavirus disease (COVID)-19 pandemic forced an unprecedented period of challenge to the NHS in the UK where hip fractures in the elderly population are a major public health concern. There are approximately 76,000 hip fractures in the UK each year which make up a substantial proportion of the trauma workload of an average orthopaedic unit. This study aims to assess the impact of the COVID-19 pandemic on hip fracture care service and the emerging lessons to withstand any future outbreaks. Methods. Data were collected retrospectively on 157 hip fractures admitted from March to May 2019 and 2020. The 2020 group was further subdivided into COVID-positive and COVID-negative. Data including the four-hour target, timing to imaging, hours to operation, anaesthetic and operative details, intraoperative complications, postoperative reviews, COVID status, Key Performance Indicators (KPIs), length of stay, postoperative complications, and the 30-day mortality were compiled from computer records and our local National Hip Fracture Database (NHFD) export data. Results. Hip fractures and inpatient falls significantly increased by 61.7% and 7.2% respectively in the 2020 group. A significant difference was found among the three groups regarding anaesthetic preparation time, anaesthetic time, and recovery time. The mortality rate in the 2020 COVID-positive group (36.8%) was significantly higher than both the 2020 COVID-negative and 2019 groups (11.5% and 11.7% respectively). The hospital stay was significantly higher in the COVID-positive group (mean of 24.21 days (SD 19.29)). Conclusion. COVID-19 has had notable effects on the hip fracture care service: hip fracture rates increased significantly. There were inefficiencies in theatre processes for which we have recommended the use of alternate theatres. COVID-19 infection increased the 30-day mortality and hospital stay in hip fractures. More research needs to be done to reduce this risk. Cite this article: Bone Joint Open 2020;1-9:530–540

Aims. Tourniquets have potential adverse effects including postoperative thigh pain, likely caused by their ischaemic and possible compressive effects. The aims of this preliminary study were to determine if it is possible to directly measure intramuscular pH in human subjects over time, and to measure the intramuscular pH changes resulting from tourniquet ischaemia in patients undergoing knee arthroscopy. Methods. For patients undergoing short knee arthroscopic procedures, a sterile calibrated pH probe was inserted into the anterior fascial compartment of the leg after skin preparation, but before tourniquet inflation. The limb was elevated for three minutes prior to tourniquet inflation to 250 mmHg or 300 mmHg. Intramuscular pH was recorded at one-second intervals throughout the procedure and for 20 minutes following tourniquet deflation. Probe-related adverse events were recorded. Results. A total of 27 patients were recruited to the study. Mean tourniquet time was 21 minutes (10 to 56). Tourniquet pressure was 300 mmHg for 21 patients and 250 mmHg for six patients. Mean muscle pH prior to tourniquet inflation was 6.80. Muscle pH decreased upon tourniquet inflation, with a steeper fall in the first ten minutes than for the rest of the procedure. Change in muscle pH was significant after five minutes of tourniquet ischaemia (p < 0.001). Mean muscle pH prior to tourniquet release was 6.58 and recovered to 6.75 within 20 minutes following release. No probe related adverse events were recorded. Conclusion. It is possible to directly measure skeletal muscle pH in human subjects over time. Tourniquet ischaemia results in a decrease in human skeletal muscle pH over time during short procedures. Cite this article: Bone Joint Res 2021;10(6):363–369

Aims. Various surgical techniques have been described for total hip arthroplasty (THA) in patients with Crowe type III dislocated hips, who have a large acetabular bone defect. The aim of this study was to evaluate the long-term clinical results of patients in whom anatomical reconstruction of the acetabulum was performed using a cemented acetabular component and autologous bone graft from the femoral neck. Methods. A total of 22 patients with Crowe type III dislocated hips underwent 28 THAs using bone graft from the femoral neck between 1979 and 2000. A Charnley cemented acetabular component was placed at the level of the true acetabulum after preparation with bone grafting. All patients were female with a mean age at the time of surgery of 54 years (35 to 68). A total of 18 patients (21 THAs) were followed for a mean of 27.2 years (20 to 33) after the operation. Results. Radiographs immediately after surgery showed a mean vertical distance from the centre of the hip to the teardrop line of 21.5 mm (SD 3.3; 14.5 to 30.7) and a mean cover of the acetabular component by bone graft of 46% (SD 6%; 32% to 60%). All bone grafts united without collapse, and only three acetabular components loosened. The rate of survival of the acetabular component with mechanical loosening or revision as the endpoint was 86.4% at 25 years after surgery. Conclusion. The technique of using autologous bone graft from the femoral neck and placing a cemented acetabular component in the true acetabulum can provide good long-term outcomes in patients with Crowe type III dislocated hips. Cite this article: Bone Joint J 2021;103-B(2):299–304

Objectives. Platelet-rich fibrin matrix (PRFM) has been proved to enhance tenocyte proliferation but has mixed results when used during rotator cuff repair. The optimal PRFM preparation protocol should be determined before clinical application. To screen the best PRFM to each individual’s tenocytes effectively, small-diameter culture wells should be used to increase variables. The gelling effect of PRFM will occur when small-diameter culture wells are used. A co-culture device should be designed to avoid this effect. Methods. Tenocytes harvested during rotator cuff repair and blood from a healthy volunteer were used. Tenocytes were seeded in 96-, 24-, 12-, and six-well plates and co-culture devices. Appropriate volumes of PRFM, according to the surface area of each culture well, were treated with tenocytes for seven days. The co-culture device was designed to avoid the gelling effect that occurred in the small-diameter culture well. Cell proliferation was analyzed by water soluble tetrazolium-1 (WST-1) bioassay. Results. The relative quantification (condition/control) of WST-1 assay on day seven revealed a significant decrease in tenocyte proliferation in small-diameter culture wells (96 and 24 wells) due to the gelling effect. PRFM in large-diameter culture wells (12 and six wells) and co-culture systems induced a significant increase in tenocyte proliferation compared with the control group. The gelling effect of PRFM was avoided by the co-culture device. Conclusion. When PRFM and tenocytes are cultured in small-diameter culture wells, the gelling effect will occur and make screening of personalized best-fit PRFM difficult. This effect can be avoided with the co-culture device. Cite this article: C-H. Chiu, P. Chen, W-L. Yeh, A. C-Y. Chen, Y-S. Chan, K-Y. Hsu, K-F. Lei. The gelling effect of platelet-rich fibrin matrix when exposed to human tenocytes from the rotator cuff in small-diameter culture wells and the design of a co-culture device to overcome this phenomenon. Bone Joint Res 2019;8:216–223. DOI: 10.1302/2046-3758.85.BJR-2018-0258.R1

Objectives. Previous studies have evidenced cement-in-cement techniques as reliable in revision arthroplasty. Commonly, the original cement mantle is reshaped, aiding accurate placement of the new stem. Ultrasonic devices selectively remove cement, preserve host bone, and have lower cortical perforation rates than other techniques. As far as the authors are aware, the impact of ultrasonic devices on final cement-in-cement bonds has not been investigated. This study assessed the impact of cement removal using the Orthosonics System for Cemented Arthroplasty Revision (OSCAR; Orthosonics) on final cement-in-cement bonds. Methods. A total of 24 specimens were manufactured by pouring cement (Simplex P Bone Cement; Stryker) into stainless steel moulds, with a central rod polished to Stryker Exeter V40 specifications. After cement curing, the rods were removed and eight specimens were allocated to each of three internal surface preparation groups: 1) burr; 2) OSCAR; and 3) no treatment. Internal holes were recemented, and each specimen was cut into 5 mm discs. Shear testing of discs was completed by a technician blinded to the original grouping, recording ultimate shear strengths. Scanning electron microscopy (SEM) was completed, inspecting surfaces of shear-tested specimens. Results. The mean shear strength for OSCAR-prepared specimens (33.6 MPa) was significantly lower than for the control (46.3 MPa) and burr (45.8 MPa) groups (p < 0.001; one-way analysis of variance (ANOVA) with Tukey’s post hoc analysis). There was no significant difference in shear strengths between control and burr groups (p = 0.57). Scanning electron microscopy of OSCAR specimens revealed evidence of porosity undiscovered in previous studies. Conclusion. Results show that the cement removal technique impacts on final cement-in-cement bonds. This in vitro study demonstrates significantly weaker bonds when using OSCAR prior to recementation into an old cement mantle compared with cement prepared with a burr or no treatment. This infers that care must be taken in surgical decision-making regarding cement removal techniques used during cement-in-cement revision arthroplasty, suggesting that the risks and benefits of ultrasonic cement removal need consideration. Cite this article: A. Liddle, M. Webb, N. Clement, S. Green, J. Liddle, M. German, J. Holland. Ultrasonic cement removal in cement-in-cement revision total hip arthroplasty: What is the effect on the final cement-in-cement bond? Bone Joint Res 2019;8:246–252. DOI: 10.1302/2046-3758.86.BJR-2018-0313.R1

Objectives. Platelet-rich plasma (PRP) is being used increasingly often in the clinical setting to treat tendon-related pathologies. Yet the optimal PRP preparations to promote tendon healing in different patient populations are poorly defined. Here, we sought to determine whether increasing the concentration of platelet-derived proteins within a derivative of PRP, platelet lysate (PL), enhances tenocyte proliferation and migration in vitro, and whether the mitogenic properties of PL change with donor age. Methods. Concentrated PLs from both young (< 50 years) and aged (> 50 years) donors were prepared by exposing pooled PRP to a series of freeze-thaw cycles followed by dilution in plasma, and the levels of several platelet-derived proteins were measured using multiplex immunoassay technology. Human tenocytes were cultured with PLs to simulate a clinically relevant PRP treatment range, and cell growth and migration were assessed using DNA quantitation and gap closure assays, respectively. Results. Platelet-derived protein levels increased alongside higher PL concentrations, and PLs from both age groups improved tenocyte proliferation relative to control conditions. However, PLs from aged donors yielded a dose-response relationship in tenocyte behaviour, with higher PL concentrations resulting in increased tenocyte proliferation and migration. Conversely, no significant differences in tenocyte behaviour were detected when increasing the concentration of PLs from younger donors. Conclusion. Higher PL concentrations, when prepared from the PRP of aged but not young donors, were more effective than lower PL concentrations at promoting tenocyte proliferation and migration in vitro. Cite this article: D. R. Berger, C. J. Centeno, N. J. Steinmetz. Platelet lysates from aged donors promote human tenocyte proliferation and migration in a concentration-dependent manner. Bone Joint Res 2019;8:32–40. DOI: 10.1302/2046-3758.81.BJR-2018-0164.R1

Aims. COVID-19 necessitated abrupt changes in trauma service delivery. We compare the demographics and outcomes of patients treated during lockdown to a matched period from 2019. Findings have important implications for service development. Methods. A split-site service was introduced, with a COVID-19 free site treating the majority of trauma patients. Polytrauma, spinal, and paediatric trauma patients, plus COVID-19 confirmed or suspicious cases, were managed at another site. Prospective data on all trauma patients undergoing surgery at either site between 16 March 2020 and 31 May 2020 was collated and compared with retrospective review of the same period in 2019. Patient demographics, injury, surgical details, length of stay (LOS), COVID-19 status, and outcome were compared. Results. There were 1,004 urgent orthopaedic trauma patients (604 in 2019; 400 in 2020). Significant reductions in time to theatre and LOS stay were observed. COVID-19 positive status was confirmed in 4.5% (n = 18). The COVID-19 mortality rate was 1.8% (n = 7). Day-case surgery comprised 47.8% (n = 191), none testing positive for COVID-19 or developing clinically significant COVID-19 symptoms requiring readmission, at a minimum of 17 days follow-up. Conclusion. The novel split-site service, segregating suspected or confirmed COVID-19 cases, minimized onward transmission and demonstrated improved outcomes regarding time to surgery and LOS, despite altered working patterns and additional constraints. Day-surgery pathways appear safe regarding COVID-19 transmission. Lessons learned require dissemination and should be sustained in preparation for a potential second wave or, the return of a “normal” non-COVID workload. Cite this article: Bone Joint Open 2020;1-9:568–575

Objectives. The purpose of this study was to examine the bactericidal efficacy of hydrogen peroxide (H. 2. O. 2. ) on Cutibacterium acnes (C. acnes). We hypothesize that H. 2. O. 2. reduces the bacterial burden of C. acnes. Methods. The effect of H. 2. O. 2. was assessed by testing bactericidal effect, time course analysis, growth inhibition, and minimum bactericidal concentration. To assess the bactericidal effect, bacteria were treated for 30 minutes with 0%, 1%, 3%, 4%, 6%, 8%, or 10% H. 2. O. 2. in saline or water and compared with 3% topical H. 2. O. 2. solution. For time course analysis, bacteria were treated with water or saline (controls), 3% H. 2. O. 2. in water, 3% H. 2. O. 2. in saline, or 3% topical solution for 5, 10, 15, 20, and 30 minutes. Results were analyzed with a two-way analysis of variance (ANOVA) (p < 0.05). Results. Minimum inhibitory concentration of H. 2. O. 2. after 30 minutes is 1% for H. 2. O. 2. prepared in saline and water. The 3% topical solution was as effective when compared with the 1% H. 2. O. 2. prepared in saline or water. The controls of both saline and water showed no reduction of bacteria. After five minutes of exposure, all mixtures of H. 2. O. 2. reduced the percentage of live bacteria, with the topical solution being most effective (p < 0.0001). Maximum growth inhibition was achieved with topical 3% H. 2. O. 2. . Conclusion. The inexpensive and commercially available topical solution of 3% H. 2. O. 2. demonstrated superior bactericidal effect as observed in the minimum bactericidal inhibitory concentration, time course, and colony-forming unit (CFU) inhibition assays. These results support the use of topical 3% H. 2. O. 2. for five minutes before surgical skin preparation prior to shoulder surgery to achieve eradication of C. acnes for the skin. Cite this article: P. Hernandez, B. Sager, A. Fa, T. Liang, C. Lozano, M. Khazzam. Bactericidal efficacy of hydrogen peroxide on Cutibacterium acnes. Bone Joint Res 2019;8:3–10. DOI: 10.1302/2046-3758.81.BJR-2018-0145.R1

Objectives. The ability to determine human bone stiffness is of clinical relevance in many fields, including bone quality assessment and orthopaedic prosthesis design. Stiffness can be measured using compression testing, an experimental technique commonly used to test bone specimens in vitro. This systematic review aims to determine how best to perform compression testing of human bone. Methods. A keyword search of all English language articles up until December 2017 of compression testing of bone was undertaken in Medline, Embase, PubMed, and Scopus databases. Studies using bulk tissue, animal tissue, whole bone, or testing techniques other than compression testing were excluded. Results. A total of 4712 abstracts were retrieved, with 177 papers included in the analysis; 20 studies directly analyzed the compression testing technique to improve the accuracy of testing. Several influencing factors should be considered when testing bone samples in compression. These include the method of data analysis, specimen storage, specimen preparation, testing configuration, and loading protocol. Conclusion. Compression testing is a widely used technique for measuring the stiffness of bone but there is a great deal of inter-study variation in experimental techniques across the literature. Based on best evidence from the literature, suggestions for bone compression testing are made in this review, although further studies are needed to establish standardized bone testing techniques in order to increase the comparability and reliability of bone stiffness studies. Cite this article: S. Zhao, M. Arnold, S. Ma, R. L. Abel, J. P. Cobb, U. Hansen, O. Boughton. Standardizing compression testing for measuring the stiffness of human bone. Bone Joint Res 2018;7:524–538. DOI: 10.1302/2046-3758.78.BJR-2018-0025.R1

Aims

To determine whether platelet-rich plasma (PRP) injection improves outcomes two years after acute Achilles tendon rupture.

Aims

Hand trauma, consisting of injuries to both the hand and the wrist, are a common injury seen worldwide. The global age-standardized incidence of hand trauma exceeds 179 per 100,000. Hand trauma may require surgical management and therefore result in significant costs to both healthcare systems and society. Surgical site infections (SSIs) are common following all surgical interventions, and within hand surgery the risk of SSI is at least 5%. SSI following hand trauma surgery results in significant costs to healthcare systems with estimations of over £450 per patient. The World Health Organization (WHO) have produced international guidelines to help prevent SSIs. However, it is unclear what variability exists in the adherence to these guidelines within hand trauma. The aim is to assess compliance to the WHO global guidelines in prevention of SSI in hand trauma.