Aims. Intraoperative pressure sensors allow surgeons to quantify soft-tissue balance during total knee arthroplasty (TKA). The aim of this study was to determine whether using sensors to achieve soft-tissue balance was more effective than manual balancing in improving outcomes in TKA. Methods. A multicentre randomized trial compared the outcomes of sensor balancing (SB) with manual balancing (MB) in 250 patients (285 TKAs). The primary outcome measure was the mean difference in the four Knee injury and Osteoarthritis Outcome Score subscales (ΔKOOS. 4. ) in the two groups, comparing the preoperative and two-year scores. Secondary outcomes included intraoperative balance data, additional patient-reported outcome measures (PROMs), and functional measures. Results. There was no significant difference in ΔKOOS. 4. between the two groups at two years (mean difference 0.4 points (95% confidence interval (CI) -4.6 to 5.4); p = 0.869), and multiple regression found that SB was not associated with a significant ΔKOOS. 4. (0.2-point increase (95% CI -5.1 to 4.6); p = 0.924). There were no significant differences between groups in other PROMs. Six-minute walking distance was significantly increased in the SB group (mean difference 29 metres; p = 0.015). Four-times as many TKAs were unbalanced in the MB group (36.8% MB vs 9.4% SB; p < 0.001). Irrespective of group assignment, no differences were found in any PROM when increasing ICPD thresholds defined balance. Conclusion. Despite improved quantitative soft-tissue balance, the use of sensors intraoperatively did not differentially improve the clinical or functional outcomes two years after TKA. These results question whether a more precisely balanced TKA that is guided by sensor data, and often achieved by more balancing interventions, will ultimately have a significant effect on clinical outcomes. Cite this article: Bone Joint J 2022;104-B(5):604–612

Prediction tools are instruments which are commonly used to estimate the prognosis in oncology and facilitate clinical decision-making in a more personalized manner. Their popularity is shown by the increasing numbers of prediction tools, which have been described in the medical literature. Many of these tools have been shown to be useful in the field of soft-tissue sarcoma of the extremities (eSTS). In this annotation, we aim to provide an overview of the available prediction tools for eSTS, provide an approach for clinicians to evaluate the performance and usefulness of the available tools for their own patients, and discuss their possible applications in the management of patients with an eSTS. Cite this article: Bone Joint J 2022;104-B(9):1011–1016

Aims. Several studies have reported that patients presenting during the evening or weekend have poorer quality healthcare. Our objective was to examine how timely surgery for patients with severe open tibial fracture varies by day and time of presentation and by type of hospital. This cohort study included patients with severe open tibial fractures from the Trauma Audit and Research Network (TARN). Methods. Provision of prompt surgery (debridement within 12 hours and soft-tissue coverage in 72 hours) was examined, using multivariate logistic regression to derive adjusted risk ratios (RRs). Time was categorized into three eight-hour intervals for each day of the week. The models were adjusted for treatment in a major trauma centre (MTC), sex, age, year of presentation, injury severity score, injury mechanism, and number of operations each patient received. Results. We studied 8,258 patients from 175 hospitals. Patients presenting during the day (08:00 to 15:59; risk ratio (RR) 1.11, 95% confidence interval (CI) 1.02 to 1.20) were more likely to receive debridement within 12 hours, and patients presenting at night (16:00 to 23:59; RR 0.56, 95% CI 0.51 to 0.62) were less likely to achieve the target; triage to a MTC had no effect. Day of presentation was associated with soft-tissue coverage within 72 hours; patients presenting on a Thursday or Friday being less likely to receive this surgery within 72 hours (Thursday RR 0.88, 95% CI 0.81 to 0.97; Friday RR 0.89, 95% CI 0.81 to 0.98), and the standard less likely to be achieved for those treated in ‘non-MTC’ hospitals (RR 0.76, 95% CI 0.70 to 0.82). Conclusion. Variations in care were observed for timely surgery for severe open tibial fractures with debridement surgery affected by time of presentation and soft-tissue coverage affected by day of presentation and type of hospital. The variation is unwarranted and highlights that there are opportunities to substantially improve the delivery and quality of care for patients with severe open tibial fracture. Cite this article: Bone Jt Open 2022;3(12):941–952

Aim. Fracture-related infection (FRI) is a severe post-traumatic complication which can be accompanied with a soft-tissue defect or an avital soft-tissue envelope. In these cases, a thoroughly planned orthoplastic approach is imperative since a vital soft-tissue envelope is mandatory to achieve fracture union and infection eradication. The aim of our study was to analyse plastic surgical aspects in the management of FRIs, including the type and outcome of soft-tissue reconstruction (STR), and to investigate the long-term outcome of FRI after STR. Method. Patients with a lower leg FRI requiring STR that were treated from 2010 to 2018 at our center were included in this retrospective analysis. STR involved the use of local, pedicled and free flaps. The primary outcome was the success rate of STR, and the secondary outcome was long-term fracture consolidation and cure of infection. Results. Overall, 145 patients with lower leg FRI were identified, of whom 58 (40%) received STR. Muscle flaps were applied in 38, fascio-cutaneous flaps in 19 and a composite osteo-cutaneous flap in one case. All patients underwent successful STR (primary STR in 51/58 patients, 7/58 patients needed secondary STR). A high Charlson Comorbidity Index Score was a significant risk factor for flap failure (p=0.011). Patients with free-flap STR developed significantly more severe complications and needed more surgical interventions (Clavien-Dindo ≥IIIa; p=0.001). Out of the 43 patients that completed long-term follow-up (mean 24 months), fracture consolidation was achieved in 32 and infection eradication in 31. Polymicrobial infection was a significant risk factor for fracture non-union (p=0.002). American Society of Anesthesiologists (ASA) classification of 3 or higher (p=0.040) was a risk factor for persistence or recurrence of infection. Conclusions. In our population, 58/145 patients with FRI required STR. STR was successful in all patients eventually, in 7/58 patients secondary STR was necessary. Therefore, STR should be sought even if primary STR fails. Despite successful STR, the long-term composite outcome showed a high rate of failed fracture consolidation and failed eradication of infection, which was independent of primary STR failure

Aim. Reconstruction of composite soft-tissue defects with extensor apparatus deficiency in patients with periprosthetic joint infection (PJI) of the knee is challenging. We present a single-centre multidisciplinary orthoplastic treatment concept based on a retrospective outcome analysis over 20 years. Method. One-hundred sixty-seven patients had PJI after total knee arthroplasty. Plastic surgical reconstruction of a concomitant perigenicular soft-tissue defect was indicated in 49 patients. Of these, seven presented with extensor apparatus deficiency. Results. One patient underwent primary arthrodesis and six patients underwent autologous reconstruction of the extensor apparatus. The principle to reconstruct missing tissue ‘like with like’ was thereby favoured: Two patients with a wide soft-tissue defect received a free anterolateral thigh flap with fascia lata; one patient with a smaller soft-tissue defect received a free sensate, extended lateral arm flap with triceps tendon; and three patients received a pedicled medial sural artery perforator gastrocnemius flap, of which one with Achilles tendon. Despite good functional results 1 year later, long-term follow-up revealed that two patients had to undergo knee arthrodesis because of recurrent infection and one patient was lost to follow-up. In parts, results have been published under doi: 10.7150/jbji.47018. Conclusions. A treatment concept and its rationale, based on a single-centre experience, is presented. It differentiates between various types of soft-tissue defects and shows reconstructive options following the concept to reconstruct ‘like with like’. Despite good results 1 year postoperatively, PJI of the knee with extensor apparatus deficiency remains a dreaded combination with a poor long-term outcome

The kinematic alignment (KA) approach to total knee arthroplasty (TKA) has recently increased in popularity. Accordingly, a number of derivatives have arisen and have caused confusion. Clarification is therefore needed for a better understanding of KA-TKA. Calipered (or true, pure) KA is performed by cutting the bone parallel to the articular surface, compensating for cartilage wear. In soft-tissue respecting KA, the tibial cutting surface is decided parallel to the femoral cutting surface (or trial component) with in-line traction. These approaches are categorized as unrestricted KA because there is no consideration of leg alignment or component orientation. Restricted KA is an approach where the periarthritic joint surface is replicated within a safe range, due to concerns about extreme alignments that have been considered ‘alignment outliers’ in the neutral mechanical alignment approach. More recently, functional alignment and inverse kinematic alignment have been advocated, where bone cuts are made following intraoperative planning, using intraoperative measurements acquired with computer assistance to fulfill good coordination of soft-tissue balance and alignment. The KA-TKA approach aims to restore the patients’ own harmony of three knee elements (morphology, soft-tissue balance, and alignment) and eventually the patients’ own kinematics. The respective approaches start from different points corresponding to one of the elements, yet each aim for the same goal, although the existing implants and techniques have not yet perfectly fulfilled that goal

Aims. Wrist arthroscopy is a standard procedure in hand surgery for diagnosis and treatment of wrist injuries. Even though not generally recommended for similar procedures, general administration of perioperative antibiotic prophylaxis (PAP) is still widely used in wrist arthroscopy. Methods. A clinical ambispective dual-centre study was performed to determine whether PAP reduces postoperative infection rates after soft tissue-only wrist arthroscopies. Retrospective and prospective data was collected at two hospitals with departments specialized in hand surgery. During the study period, 464 wrist arthroscopies were performed, of these 178 soft-tissue-only interventions met the study criteria and were included. Signs of postoperative infection and possible adverse drug effects (ADEs) of PAP were monitored. Additionally, risk factors for surgical site infection (SSIs), such as diabetes mellitus and BMI, were obtained. Results. The overall infection rate of SSI was zero. Neither in the PAP group (n = 69) nor in the control group (n = 109) were signs of postoperative infection observed. Observed symptoms of ADEs were three-times higher in the PAP group when compared to the control-group (16.3 vs 5.5%; p = 0.043). No major ADEs were observed, but one in ten patients in the PAP group reported mild to severe intestinal or hypersensitivity symptoms. Conclusion. We demonstrate that the number needed to treat (NNT) with PAP to prevent one postoperative infection in soft-tissue arthroscopies of the wrist is > 109. Conversely, symptoms of ADEs were reported by one out of ten patients given PAP. Considering the high NNT to prevent postoperative infection and the large number of ADEs caused by PAP, we recommend not to use PAP routinely in soft-tissue arthroscopies of the wrist. Subsequent large-scale studies should be conducted to substantiate these results. Cite this article: Bone Jt Open 2023;4(4):219–225

Aims. Custom-made partial pelvis replacements (PPRs) are increasingly used in the reconstruction of large acetabular defects and have mainly been designed using a triflange approach, requiring extensive soft-tissue dissection. The monoflange design, where primary intramedullary fixation within the ilium combined with a monoflange for rotational stability, was anticipated to overcome this obstacle. The aim of this study was to evaluate the design with regard to functional outcome, complications, and acetabular reconstruction. Methods. Between 2014 and 2023, 79 patients with a mean follow-up of 33 months (SD 22; 9 to 103) were included. Functional outcome was measured using the Harris Hip Score and EuroQol five-dimension questionnaire (EQ-5D). PPR revisions were defined as an endpoint, and subgroups were analyzed to determine risk factors. Results. Implantation was possible in all cases with a 2D centre of rotation deviation of 10 mm (SD 5.8; 1 to 29). PPR revision was necessary in eight (10%) patients. HHS increased significantly from 33 to 72 postoperatively, with a mean increase of 39 points (p < 0.001). Postoperative EQ-5D score was 0.7 (SD 0.3; -0.3 to 1). Risk factor analysis showed significant revision rates for septic indications (p ≤ 0.001) as well as femoral defect size (p = 0.001). Conclusion. Since large acetabular defects are being treated surgically more often, custom-made PPR should be integrated as an option in treatment algorithms. Monoflange PPR, with primary iliac fixation, offers a viable treatment option for Paprosky III defects with promising functional results, while requiring less soft-tissue exposure and allowing immediate full weightbearing. Cite this article: Bone Jt Open 2024;5(8):688–696

Introduction/Aim. Mid-flexion instability is a well-documented, but often poorly understood cause of failure of TKA. NAVIO robotic-assisted TKA (RA-TKA) offers a novel, integrative approach as a planning, execution as well as an evaluation tool in TKA surgery. RA-TKA provides a hybrid planning technique of measured resection and gap balancing- generating a predictive soft-tissue balance model, prior to making cuts. Concurrently, the system uses a semi-active robot to facilitate both the execution and verification of the plan, as it pertains to both the static and dynamic anatomy. The goal of this study was to assess the ability of the NAVIO RA-TKA to plan, execute and deliver an individualized approach to the soft-tissue balance of the knee, specifically in the “mid-flexion” arc of motion. Materials and Methods. Between May and September 2018, 50 patients underwent NAVIO RA-TKA. Baseline demographics were collected, including age, gender, BMI, and range of motion. The NAVIO imageless technique was used to plan the procedure, including: surface-mapping of the static anatomy; objective assessment of the dynamic, soft-tissue anatomy; and then application of a hybrid of measured-resection and gap-balancing technique. Medial and lateral gaps as predicted by the software were recorded throughout the entire arc of motion at 15° increments. After executing the plan and placing the components, actual medial and lateral gaps were recorded throughout the arc of motion. Results. In the assessment of coronal-plane balance, the average deviation from the predicted plan between 0–90° was 0.9mm in both the medial and lateral compartments (range 0.5–1.2mm). In the mid-flexion arc (15–75°), final soft-tissue stability was within 1.0mm of the predictive plan (range 0.9–1.2mm). Discussion/Conclusions. In this study, NAVIO RA-TKA demonstrated a highly accurate and reproducible surgical technique to plan, execute and verify a balanced a soft-tissue envelope in TKA. Objective soft-tissue balancing of the TKA can now be performed, including the mid-flexion arc of motion. Further analysis can determine if these objective measurements will translate into improved patient-reported outcome scores

Introduction. Autologous fat grafting has favourable potential as a regenerative strategy and is the current gold-standard to repair large contour defects, as needed in breast reconstruction after mastectomy and traumatic soft tissue reconstruction. Clinically, there is a limit on the volume of lipoaspirate which can be utilised to repair a soft-tissue defect. Surgical complications are the result of poor structural fidelity of lipoaspirate and graft resorption as a filling material and are hindered further by poor graft vascularisation. This study aims to develop injectable lipoaspirate-derived adipose tissue grafts with enhanced biologically and clinically-admissible structural and functional properties adopting light photocrosslinking of unmodified lipoaspirate. Methods. Patient-derived lipoaspirate was harvested and crosslinked using novel photoinitiator and exposure to visible light (wavelength 450nm) in surgery, establishing bonds between extracellular matrix (ECM) proteins within the material. The degree of crosslinking was tuned (photoinitiator concentration, light exposure, light intensity) and covalent bond formation measured using mass spectrometry. To predict patient response, SWATH-MS was used to identify differences in patient ECM and crosslinked grafts were implanted in vivo using a subcutaneous mouse model. Functional vessel formation and resorption were quantified using micro-CT and tissue-remodelling was assessed via histology. Results. There was an increase in the relative abundance of covalent bonds present with increasing degree of crosslinking. When injected, crosslinked lipoaspirate had better shape fidelity compared with native lipoaspirate – demonstrated by a smaller fibre diameter. Crosslinked lipoaspirate remained viable over long term culture and resulted in more predictable resorption profiles when implanted in vivo. Conclusions. The crosslinking approach described here is tunable and functional across different patient samples. Improving the structural properties of lipoaspirate through minimal manipulation has clinical utility for the delivery of grafts with higher shape fidelity and therefore increased graft survival when implanted

Aims. Cell-free DNA (cfDNA) and circulating tumour DNA (ctDNA) are used for prognostication and monitoring in patients with carcinomas, but their utility is unclear in sarcomas. The objectives of this pilot study were to explore the prognostic significance of cfDNA and investigate whether tumour-specific alterations can be detected in the circulation of sarcoma patients. Methods. Matched tumour and blood were collected from 64 sarcoma patients (n = 70 samples) prior to resection of the primary tumour (n = 57) or disease recurrence (n = 7). DNA was isolated from plasma, quantified, and analyzed for cfDNA. A subset of cases (n = 6) underwent whole exome sequencing to identify tumour-specific alterations used to detect ctDNA using digital droplet polymerase chain reaction (ddPCR). Results. Cell-free was present in 69 of 70 samples above 0.5 ng/ml. Improved disease-free survival was found for patients with lower cfDNA levels (90% vs 48% at one-year for ≤ 6 ng/ml and > 6 ng/ml, respectively; p = 0.005). Digital droplet PCR was performed as a pilot study and mutant alleles were detectable at 0.5% to 2.5% of the wild type genome, and at a level of 0.25 ng tumour DNA. Tumour-specific alterations (ctDNA) were found in five of six cases. Conclusion. This work demonstrates the feasibility and potential utility of cfDNA and ctDNA as biomarkers for bone and soft-tissue sarcomas, despite the lack of recurrent genomic alterations. A larger study is required to validate these findings. Cite this article: Bone Joint Res 2021;10(9):602–610

The NZ Standards of Service Provision for Sarcoma patients were developed by the NZ Sarcoma working group and published by the Ministry of Health (MOH) in 2013. Although not formally enacted by the MOH we aimed to determine the impact of these published standards and referral pathways on disease-specific survival of patients with soft-tissue sarcoma in NZ. The Middlemore Musculoskeletal Tumour Unit database was searched. Patients referred for treatment in our centre with a diagnosis of soft tissue sarcoma in the five-year period before (n=115) and after (n=155) were included. We excluded patients with bone sarcomas and retroperitoneal soft tissue sarcomas. The rate of referral after inappropriate treatment reduced after implementation of the Standards (24% vs 12%, p=0.010). The number of patients referred with tumours larger than 50mm decreased (74.8% vs 72.3%, p=0.021) and fewer had metastases at diagnosis (11.3% vs 3.2%, p=0.017). Mortality was lower in the group after introduction of the Standards (45% vs 30%, p=0.017). The estimated disease-specific survival curve between the two groups shows a trend towards increased survival in the post-standards group, although not reaching statistical significance. Local recurrence rate and metastasis rate after definitive treatment were similar between the two groups. Patients had a shorter duration of symptoms before referral in the post-Standards group although this was not statistically significant. Since implementation of the Standards, patients have been referred more promptly, with fewer inappropriate treatments. The time to mortality curve indicates a trend towards improved disease-specific survival. We conclude that the pathway for investigation and referral for this condition has become clearer, supporting the ongoing use of the Sarcoma Standards, and that these should be formally implemented by the MOH

Aims. The aim of this study was to perform the first population-based description of the epidemiological and health economic burden of fracture-related infection (FRI). Methods. This is a retrospective cohort study of operatively managed orthopaedic trauma patients from 1 January 2007 to 31 December 2016, performed in Queensland, Australia. Record linkage was used to develop a person-centric, population-based dataset incorporating routinely collected administrative, clinical, and health economic information. The FRI group consisted of patients with International Classification of Disease 10th Revision diagnosis codes for deep infection associated with an implanted device within two years following surgery, while all others were deemed not infected. Demographic and clinical variables, as well as healthcare utilization costs, were compared. Results. There were 111,402 patients operatively managed for orthopaedic trauma, with 2,775 of these (2.5%) complicated by FRI. The development of FRI had a statistically significant association with older age, male sex, residing in rural/remote areas, Aboriginal or Torres Strait Islander background, lower socioeconomic status, road traffic accident, work-related injuries, open fractures, anatomical region (lower limb, spine, pelvis), high injury severity, requiring soft-tissue coverage, and medical comorbidities (univariate analysis). Patients with FRI had an eight-times longer median inpatient length of stay (24 days vs 3 days), and a 2.8-times higher mean estimated inpatient hospitalization cost (AU$56,565 vs AU$19,773) compared with uninfected patients. The total estimated inpatient cost of the FRI cohort to the healthcare system was AU$156.9 million over the ten-year period. Conclusion. The results of this study advocate for improvements in trauma care and infection management, address social determinants of health, and highlight the upside potential to improve prevention and treatment strategies. Cite this article: Bone Joint J 2024;106-B(1):77–85

Aims. This study estimated trends in incidence of open fractures and the adherence to clinical standards for open fracture care in England. Methods. Longitudinal data collected by the Trauma Audit and Research Network were used to identify 38,347 patients with open fractures, and a subgroup of 12,170 with severe open fractures of the tibia, between 2008 and 2019 in England. Incidence rates per 100,000 person-years and 95% confidence intervals were calculated. Clinical care was compared with the British Orthopaedic Association Standards for Trauma and National Major Trauma Centre audit standards. Results. In total, 60% of all open fractures occurred in males; the median age was 48 years (interquartile range (IQR) 29 to 68). Between 2012 and 2019, the overall incidence in England was 6.94 per 100,000 person-years. In males, the highest incidence observed was in those aged 20 to 29 years (11.50 per 100,000 person-years); in females, incidence increased with age, peaking at 32.11/100,000 person-years at 90 years of age and over. Among those with severe open fractures of the tibia, there was a bimodal distribution in males, peaking at 20 to 29 years (3.71/100,000 person-years) and greater than 90 years of age (2.84/100,000 person-years) respectively; among females, incidence increased with age to a peak of 9.91/100,000 person years at 90 years of age and over. There has been variable improvement with time in the clinical care standards for patients with severe open fractures of the tibia. The median time to debridement was 13.0 hours (IQR 6.4 to 20.9); almost two-thirds of patients underwent definitive soft-tissue coverage within 72 hours from 2016 to 2019. Conclusion. This is the first time the incidence of all open fractures has been studied using data from a national audit in England. While most open fractures occurred in young males, the incidence increased with age in females to a much greater level than observed in older males. The degree of missing data in the national audit is startling, and limits the certainty of inferences drawn concerning open fracture care. Cite this article: Bone Joint J 2022;104-B(6):736–746

Aim. The aim of this study was to compare outcomes between patients with diabetic foot soft-tissue infection and osteomyelitis. Methods. Medical records of patients with diabetic foot infection involving either soft-tissue (STI) or bone (OM) were retrospectively reviewed. Diagnosis was determined by bone culture, bone histopathology or imaging with magnetic resonance imaging (MRI) or single-photon emission computed tomography (SPECT/CT). Patient outcomes were recorded up to 1 year after admission. Results. Out of 294 patients included in the study, 137 were diagnosed with STI and 157 had OM. No differences in age (p=.40), sex (p=.79), race (p=.83), body-mass index (p=.79) or type of diabetes (p=.77) were appreciated between groups. Frequency of comorbidities (neuropathy, chronic kidney disease, peripheral arterial disease) also did not differ except for increased prevalence of cardiac disease in patients with STI (86.9%) compared to those with OM (31.8%) (p<.00001) and decreased prevalence of retinopathy (24.8% vs. 35.7%) (p=.04). Patients with OM had greater C-reactive protein (p<.00001), erythrocyte sedimentation rate (p<.00001) and white blood cell count (p<.00001). Among 1-year outcomes, patients with OM more often underwent surgery (p<.00001), had lower limb amputations (p<.00001), became reinfected (p=.0007), were readmitted for the initial problem (p=.008), had longer time to healing (p=.03) and had longer hospital length of stay (p=.00002). However, no differences in 1-year mortality (p=1.000), overall 1-year readmission (p=.06) or healing within 1-year (p=.64) were appreciated. Conclusion. In our study, OM was associated with more aggressive treatment, reinfection and longer time to healing than STI. However, despite being associated with more aggressive care and readmissions, patients with diabetic foot OM has similar 1-year mortality and healing rates to those with diabetic foot STI

Introduction. There is little information available to surgeons regarding how the lateral soft-tissue structures prevent instability in knees implanted with total knee arthroplasty (TKA). The aim of this study was to quantify the lateral soft-tissue contributions to stability following cruciate retaining (CR) TKA. Methods. Nine cadaveric knees with CR TKA implants (PFC Sigma; DePuy Synthes Joint Reconstruction) were tested in a robotic system (Fig. 1) at full extension, 30°, 60°, and 90° flexion angles. ±90 N anterior-posterior force, ±8 Nm varus-valgus and ±5 Nm internal-external torque were applied at each flexion angle. The anterolateral structures (ALS, including the iliotibial band, anterolateral ligament and anterolateral capsule), the lateral collateral ligament (LCL), the popliteus tendon complex (Pop T) and the posterior cruciate ligament (PCL) were then sequentially transected. After each transection the kinematics obtained from the original loads were replayed, and the decrease in force / moment equated to the relative contributions of each soft-tissue to stabilising the applied loads. Results. In the CR TKA knee, the LCL was found to be the primary restraint to varus laxity (Fig. 2, an average 56% across all flexion angles), and was significant in internal-external rotational stability (28% and 26% respectively) and anterior drawer (16%). The ALS restrained 25% of internal rotation (Fig. 3), whilst the PCL was significant in posterior drawer only at 60° and 90° flexion. The Pop T was not found to be significant in any tests. Conclusion. This study has for the first time delineated the relative contributions of lateral structures to stability in the implanted knee. It was confirmed that the LCL is the major lateral structure in CR TKA stability throughout the arc of flexion. In the event of LCL deficiency, stability of the knee may only be restored by either changing to a more constrained implant or performing a reconstruction of the ligament. Furthermore, care should be taken when releasing the LCL to correct a valgus deformity as it may result in a combined rotational laxity pattern that cannot be overcome by the other passive lateral structures or the PCL. For figures, please contact authors directly

Aims. To evaluate the impact of negative pressure wound therapy (NPWT) on the odds of having deep infections and health-related quality of life (HRQoL) following open fractures. Methods. Patients from the Fluid Lavage in Open Fracture Wounds (FLOW) trial with Gustilo-Anderson grade II or III open fractures within the lower limb were included in this secondary analysis. Using mixed effects logistic regression, we assessed the impact of NPWT on deep wound infection requiring surgical intervention within 12 months post-injury. Using multilevel model analyses, we evaluated the impact of NPWT on the Physical Component Summary (PCS) of the 12-Item Short-Form Health Survey (SF-12) at 12 months post-injury. Results. After applying inverse probability treatment weighting to adjust for the influence of injury characteristics on type of dressing used, 1,322 participants were assessed. The odds of developing a deep infection requiring operative management within 12 months of initial surgery was 4.52-times higher in patients who received NPWT compared to those who received a standard wound dressing (95% confidence interval (CI) 1.84 to 11.12; p = 0.001). Overall, 1,040 participants were included in our HRQoL analysis, and those treated with NPWT had statistically significantly lower mean SF-12 PCS post-fracture (p < 0.001). These differences did not reach the minimally important difference for the SF-12 PCS. Conclusion. Our analysis found that patients treated with NPWT had higher odds of developing a deep infection requiring operative management within 12 months post-fracture. Due to possible residual confounding with the worst cases being treated with NPWT, we are unable to determine if NPWT has a negative effect or is simply a marker of worse injuries or poor access to early soft-tissue coverage. Regardless, our results suggest that the use of this treatment requires further evaluation. Cite this article: Bone Jt Open 2022;3(3):189–195

Aims. The Intraosseous Transcutaneous Amputation Prosthesis (ITAP) may improve quality of life for amputees by avoiding soft-tissue complications associated with socket prostheses and by improving sensory feedback and function. It relies on the formation of a seal between the soft tissues and the implant and currently has a flange with drilled holes to promote dermal attachment. Despite this, infection remains a significant risk. This study explored alternative strategies to enhance soft-tissue integration. Materials and Methods. The effect of ITAP pins with a fully porous titanium alloy flange with interconnected pores on soft-tissue integration was investigated. The flanges were coated with fibronectin-functionalised hydroxyapatite and silver coatings, which have been shown to have an antibacterial effect, while also promoting viable fibroblast growth in vitro. The ITAP pins were implanted along the length of ovine tibias, and histological assessment was undertaken four weeks post-operatively. Results. The porous titanium alloy flange reduced epithelial downgrowth and increased soft-tissue integration compared with the current drilled flange. The addition of coatings did not enhance these effects. Conclusion. These results indicate that a fully porous titanium alloy flange has the potential to increase the soft-tissue seal around ITAP and reduce susceptibility to infection compared with the current design. Cite this article: Bone Joint J 2017;99-B:393–400

Complications after total knee arthroplasty (TKR) such as malalignment, instability, subluxation, excessive wear, and loosening have been attributed to poor soft-tissue balance. Traditional approaches for soft-tissue balance involve static measurements in full extension and at 90° flexion. A trial prosthesis instrumented with force transducers was used to measure soft-tissue balance through the entire range of flexion. The trial prosthesis was instrumented with four force transducers, one at each corner of the tibial tray, and was implanted in four cadaver knees and four patients intra-operatively. Tibial forces were recorded during passive knee flexion after the tibial and femoral bone cuts were made and again after soft-tissue balance was achieved using standard techniques. In all eight knees measurable imbalance was initially recorded. The differences in forces were a mean of 18 N (range, 6 to 72) mediolateral and a mean of 26 N (range, 13 to 108) anteroposterior. After a routine procedure of soft-tissue balancing, the mean imbalance between the transducers was reduced by 62 % to 87 % (p < 0.05). However, even the knees that appeared perfectly balanced at 0° and 90° flexion, some imbalance occurred [mean 22 N (range, 2 to 34)] at flexion angles other than 0° and 90°. Soft-tissue balance in TKR remains a complex concept. Even after accurate static balancing was achieved in extension and 90° flexion, dynamic measurements revealed discrepancies in mid flexion, which may explain the wide variation in knee kinematics reported after TKR and in the reported incidences of mid-flexion knee instability. Computer-aided surgical navigation systems can increase the precision and accuracy of component alignment. However, these systems cannot directly address soft-tissue balance and knee tightness. An instrumented tibial prosthesis could be a useful adjunct to enhance the value of these navigation tools

Aims. The primary objective of this study was to compare the postoperative infection rate between negative pressure wound therapy (NPWT) and conventional dressings for closed incisions following soft-tissue sarcoma (STS) surgery. Secondary objectives were to compare rates of adverse wound events and functional scores. Methods. In this prospective, single-centre, randomized controlled trial (RCT), patients were randomized to either NPWT or conventional sterile occlusive dressings. A total of 17 patients, with a mean age of 54 years (21 to 81), were successfully recruited and none were lost to follow-up. Wound reviews were undertaken to identify any surgical site infection (SSI) or adverse wound events within 30 days. The Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) score were recorded as patient-reported outcome measures (PROMs). Results. There were two out of seven patients in the control group (28.6%), and two out of ten patients in the intervention group (20%) who were diagnosed with a SSI (p > 0.999), while one additional adverse wound event was identified in the control group (p = 0.593). No significant differences in PROMs were identified between the groups at either 30 days (TESS, p = 0.987; MSTS, p = 0.951) or six-month (TESS, p = 0.400) follow-up. However, neoadjuvant radiotherapy was significantly associated with a SSI within 30 days of surgery, across all patients (p = 0.029). The mean preoperative modified Glasgow Prognostic Score (mGPS) was also significantly higher among patients who developed a postoperative adverse wound event (p = 0.028), including a SSI (p = 0.008), across both groups. Conclusion. This is the first RCT comparing NPWT with conventional dressings following musculoskeletal tumour surgery. Postoperative wound complications are common in this group of patients and we observed an overall SSI rate of 23.5%. We propose proceeding to a multicentre trial, which will help more clearly define the role of closed incision NPWT in STS surgery. Cite this article: Bone Jt Open 2021;2(12):1049–1056