It is still difficult to determine an appropriate hinge position to prevent fracture in the lateral cortex of tibia in the process of making an open wedge during biplane open wedge high tibial osteotomy. The objective of this study was to present a biomechanical basis for determining the hinge position as varus deformity. T Three-dimensional lower extremity models were constructed using Mimics. The tibial wedge started at 40 mm distal to the medial tibial plateau, and osteotomy for three hinge positions was performed toward the head of the fibula, 5 mm proximal from the head of the fibula, and 5 mm distal from the head of the fibula. The three tibial models were made with varus deformity of 5, 10, 15 degrees with heterogeneous material properties. These properties were set to heterogeneous material properties which converted from Hounsfield's unit to Young's modulus by applying empirical equation in existing studies. For a loading condition, displacement at the posterior cut plane was applied referring to Hernigou's table considering varus deformity angle. All computational analyses were performed to calculate von-mises stresses on the tibial wedges. The maximum stress increased to an average of 213±9% when the varus angle was 10 degrees compared to 5 degrees and increased to an average of 154±8.9% when the varus angle was 15 degrees compared to 10 degrees. In addition, the maximum stress of the distal position was 19 times higher than that of the mid position and 5 times higher than that of the proximal position on average. Conclusion:. For varus deformity angles, the maximum stress of the tibial wedge tended to increase as the varus deformity angle increased. For hinge position of tibial wedge, maximum stress was the lowest in the mid position, while the highest in the distal position. *This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (NRF-2022R1A2C1009995)

Introduction and Objective. Medial Knee Osteoarthritis (MKO) is associated with abnormal knee varism, this resulting in altered locomotion and abnormal loading at tibio-femoral condylar contacts. To prevent end-stage MKO, medial compartment decompression is selectively considered and, when required, executed via High Tibial Osteotomy (HTO). This is expected to restore normal knee alignment, load distribution and locomotion. In biomechanics, HTO efficacy may be investigated by a thorough analysis of the ground reaction forces (GRF), whose orientation with respect to patient-specific knee morphology should reflect knee misalignment. Although multi-instrumental assessments are feasible, a customized combination of medical imaging and gait analysis (GA), including GRF data, rarely is considered. The aim of this study was to report an original methodology merging Computed-Tomography (CT) with GA and GFR data in order to depict a realistic patient-specific representation of the knee loading status during motion before and after HTO. Materials and Methods. 25 MKO-affected patients were selected for HTO. All patients received pre-operative clinical scoring, and radiological/instrumental assessments; so far, these were also executed post-operatively at 6-month follow-up on 7 of these patients. State-of-the-art GA was performed during walking and more demanding motor tasks, like squatting, stair-climbing/descending, and chair-rising/sitting. An 8-camera motion capture system, combined with wireless electromyography, and force platforms for GRF tracking, was used together with an own established protocol. This marker-set was enlarged with 4 additional skin-based non-collinear markers, attached around the tibial-plateau rim. While still wearing these markers, all analyzed patients received full lower-limb X-ray in standing posture a CT scan of the knee in weight-bearing Subsequently, relevant DICOMs were segmented to reconstruct the morphological models of the proximal tibia and the additional reference markers, for a robust anatomical reference frame to be defined on the tibia. These marker trajectories during motion were then registered to the corresponding from CT-based 3D reconstruction. Relevant registration matrices then were used to report GRF data on the reconstructed tibial model. Intersection paths of GRF vectors with respect to the tibial-plateau plane were calculated, together with their centroids. Results. Pre-operative clinical and radiological scoring confirmed MKO and associated abnormal varism. The morphological characterization of GRF was successfully achieved pre- and post- HTO on patient-specific tibial plateau. Pre-operative GFR patterns and peaks, including those related to knee joint moments, were observed medially on the knee, as expected. In post-HTO, these resulted lateralized and much closer to the tibial plateau spine, as desired. In detail, when post- is compared to pre-op, the difference of the centroids were, on average, 54.6±18.1 mm (min÷max: 36.7÷72.8 mm) more lateral during walking and 52.5±28.5 mm (24.7÷87.6 mm) during stair climbing. When reported in % of the tibial plateau width, these values became 69.2±20.1 (46.1÷81.4) and 78.1±30.1 (43.4÷98.0), respectively. Post-op also clinical scores and GA revealed a considerable overall improvement, especially in functional performances. Conclusions. The reported novel approach allows a combination of motion data, including GFR, and tibial-plateau morphology. Relevant pre- and post-operative routine application offer a quantification of the effect of the original deformity and executed joint realignment, and an assistance for surgical planning in case of HTO as well as ideally in other orthopedic treatments

Tibial periprosthetic fracture is an important complication of the Oxford Unicompartmental Knee Replacement (OUKR). Primary fixation of cementless OUKR tibial components relies on the interference-fit of the ‘keel’ and a slot in the proximal tibia. Clinically used double blade keel saws (DKS) create slots with two grooves, generating stress concentrations where fractures may initiate. This study aimed to investigate slot factors that may influence incidence of tibial periprosthetic fractures. Slots were made in PCF20 polyurethane foam using the DKS plus/minus adjuvant rasping, single blade keel saw (SKS), and rasp-only. Round and square slots were machined with milling cutters. Compact tensile tests were conducted per ASTM E399 to determine tensile load to fracture (TLTF) and results were validated using bovine tibia. Cementless OUKR components were implanted into slots in custom polyurethane blocks and compressed to failure to determine anatomical load to fracture (ALTF). A custom MATLAB program calculated slot roundness from cross-sectional images. Round slots had higher TLTF (29.5N, SD=2.7) than square (25.2N, SD=1.7, p<0.05) and DKS slots (23.3N, SD=2.7, p<0.0001). Fractures occurred at the round slot apices, square slot corners, and deepest DKS slot grooves. ALTF was not significantly different between square and round slots. Adjuvant rasping made DKS slots significantly rounder, resulting in significantly higher TLTF, but rasping did not increase ALTF. ALTF was significantly higher for SKS (850N, SD=133, p<0.01) and rasp-only (912N, SD=100, p<0.001) slots compared to standard DKS slots (703N, SD=81). Round keel slots minimise stress concentrations and increase TLTF but do not increase ALTF. The SKS and rasp-only slots retain material at slot ends and have significantly higher ALTF. Future studies should assess saw blades that retain material and round slot ends to evaluate if their use may significantly reduce the incidence of tibial periprosthetic fracture

Treatment for delayed wound healing resulting from peripheral vascular diseases and diabetic foot ulcers remain a challenge. A novel surgical technique named Tibial Cortex Transverse Transport has been developed for treating peripheral ischaemia, with encouraging clinical effects. However, its underlying mechanisms remain unclear. In present study, we aimed to explore the wound healing effects after undergoing this novel technique via multiple ways. A novel rat model of Tibial Cortex Transverse Transport was established with a designed external fixator and effects on wound healing were investigated. All rats were randomized into 3 groups, with 12 rats per group: sham group (negative control), fixator group (positive control) and Tibial Cortex Transverse Transport group. Laser speckle perfusion imaging, vessel perfusion, histology and immunohistochemistry were used to evaluate the wound healing processes. Gross and histological examinations showed that Tibial Cortex Transverse Transport technique accelerated wound closure and enhanced the quality of the newly formed skin tissues. In Tibial Cortex Transverse Transport group, HE staining demonstrated a better epidermis and dermis recovery, while immune-histochemical staining showed that Tibial Cortex Transverse Transport technique promoted local collagen deposition. Tibial Cortex Transverse Transport technique also benefited to angiogenesis and immunomodulation. In Tibial Cortex Transverse Transport group, blood flow in the wound area was higher than that ofother groups according to laser speckle imaging with more blood vessels observed. Enhanced neovascularization was seen in the Tibial Cortex Transverse Transport group with double immune-labelling of CD31 and α-SMA. The M2 macrophages at the wound site in the Tibial Cortex Transverse Transport group was also increased. Tibial cortex transverse transport technique accelerated wound healing through enhanced angiogenesis and immunomodulation

Tibial shaft fractures require surgical stabilization preferably by intramedullary nailing. However, patients often report functional limitations even years after the injury. This study investigates the influence of the surgical approach (transpatellar vs. parapatellar) on gait performance and patient reported outcome six months after surgery. Twenty-two patients with tibial shaft fractures treated by intramedullary nailing through a transpatellar approach (TP: n=15, age 41±15, BMI 24±3) or a parapatellar approach (PP: n=7, age 34±15, BMI 23±2) and healthy, matched controls (n=22, age 39±13, BMI 24±2) were assessed by instrumented motion analysis six months after intramedullary nailing. Short musculoskeletal function assessment questionnaire (SMFA) as well as kinematic and kinetic gait data were collected during level walking. Comparisons among approach methods and control group were performed by analysis of variance and Mann-Whitney test. Six months after surgery, knee kinetics in both groups differed significantly compared to controls (p <.04). The approach method affected gait speed (TP: p = .002; PP: p = .08) and knee kinematics in the early stance phase (TP: p = .011; PP: p = .082), with the parapatellar approach showing a more favorable outcome. However, the difference between patient groups was not significant for any of the assessed gait parameters (p > .2). Also, no differences could be found in the bother index (BI) or function index (FI) of SMFA between surgical approach methods (BI: TP: Mdn = 7.2, PP: Mdn = 9.4; FI: TP: Mdn = 10.3, PP: Mdn = 9.2, p > .7). Our study demonstrates, that six months after surgery for tibial shaft fractures functional limitations remain. These limitations appear not to be different for either a trans- or a parapatellar approach for the insertion of the intramedullary nail. The findings of this study are limited by the relatively short follow up time period and small number of patients. Future studies should investigate the source of the functional limitation after intramedullary nailing of tibial shaft fractures

Abstract. Objectives. Obesity is prevalent with nearly one third of the world's population being classified as obese. Total knee arthroplasty (TKA) is an effective treatment option for high BMI patients achieving similar outcomes to non-obese patients. However, increased rates of aseptic loosening in patients with a high BMI have been reported. In patients with high BMI/body mass there is an increase in strain placed on the implant fixation interfaces. As such component fixation is a potential concern when performing TKA in the obese patient. To address this concern the use of extended tibial stems in cemented implants or cementless fixation have been advocated. Extend tibial stems are thought to improve implant stability reducing the micromotion between interfaces and consequently the risk of aseptic loosening. Cementless implants, once biologic fixation is achieved, effectively integrate into bone eliminating an interface. This retrospective study compared the use of extended tibial stems and cementless implants to conventional cemented implants in high BMI patients. Methods. From a prospectively maintained database of 3239 primary Attune TKA (Depuy, Warsaw, Indiana), obese patients (body mass index (BMI) >30 kg/m²) were retrospectively reviewed. Two groups of patients 1) using a tibial stem extension [n=162] and 2) cementless fixation [n=163] were compared to 3) a control group (n=1426) with a standard tibial stem cemented implant. All operations were performed by or under the direct supervision of specialist arthroplasty surgeons. Analysis compared the groups with respect to class I, II, and III (BMI >30kg/m², >35 kg/m², >40 kg/m²) obesity. The primary outcome measures were all-cause revision, revision for aseptic loosening, and revision for tibial loosening. Kaplan-Meier survival analysis and Cox regression models were used to compare the primary outcomes between groups. Where radiographic images at greater than 3 months post-operatively were available, radiographs were examined to compare the presence of peri-implant radiolucent lines. Results. The mean follow-up of 4.8, 3.4, and 2.5 years for cemented, stemmed, and cementless groups respectively. In total there were 34 all-cause revisions across all the groups with revision rates of 4.55, 5.50, and 0.00 per 1000-implant-years for cemented, stemmed, and cementless groups respectively. Survival Analysis did not show any significant differences between the three groups for all-all cause revision. There were 6 revisions for aseptic loosening (5 tibial and 1 femoral); all of which were in the standard cemented implant group. In contrast there were no revisions in the stemmed or cementless implant groups, however, this was not significant on survival analysis. Analysis looking at class I, II, and III obesity also did not show any significant differences in survival for all cause revision or aseptic loosening. Conclusion. This retrospective analysis showed that there were no revisions required for aseptic loosening when either a cemented stemmed or cementless implant were used in obese patients. These findings are in line with other studies showing that cementless fixation or extended stem implants are a reasonable option in obese patients who represent an increasing cohort of patients requiring TKR. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Treatment of tibial osteomyelitis can be challenging and lengthy, with numerous complications possible during rehabilitation. We report on the usage of the Taylor Spatial Frame (TSF) for a large cohort of patients, and analyse factors that affect outcomes. Between 2015-2020, 51 patients were treated with TSF for osteomyelitis at a major trauma centre. Demographic, infection and treatment factors of: age, smoking status, diabetes, and BMI, acute (<6 weeks post injury) or chronic (>6 weeks) osteomyelitis, bacteria isolated, time to debridement, therapy/surgery number of TSF, time TSF was in, antibiotic treatment period, time to partial weight bear (PWB) and full weight bear (FWB) prescriptions, were collected. Outcomes of complications and time to union were obtained. Radiological union was achieved at mean 11.0 months. Mean follow up was 24.1 months. Six and three patients were further treated with fusion and amputation respectively. Mean treatment time with TSF was 12.1 months. 78% had some complications, with pin site infection, malunion, and non-union being most prevalent. Univariate factor analysis, multicollinearity diagnostics, then multivariate model construction were performed. Staphylococcus Epidermidis in bone debridement microbiology was significantly negatively associated with pin site infection (OR 0.093, 95% CI 0.011-0.828) and malunion (OR 0.698, 95% CI 0.573-0.849), and enterococcus with non-union (OR 0.775, 95% CI 0.656-0.916), during the treatment period. Time to union was significantly positively associated with time from admission to debridement (p=0.035), time TSF was in (p=0.021), presence of complications (p=0.045), bone loss complication(p=0.037), time to FWB prescription(p=0.001). We have analysed the effectiveness of TSF in the treatment of tibial osteomyelitis, and elucidated important injury, treatment and rehabilitation factors that affect outcome. The negative bacterial-complication cross associations could be due to successful eradication as culture specific antibiotics were used postoperatively. Earlier patient full weight bearing could enhance callous formation leading to faster union

Abstract. Objective. Up to 20% of patients can remain dissatisfied following TKR. A proportion of TKRs will need early revision with aseptic loosening the most common. The ATTUNE TKR was introduced in 2011 as successor to its predicate design The PFC Sigma (DePuy Synthes, Warsaw, In). However, following reports of early failures of the tibial component there have been ongoing concerns of increased loosening rates with the ATTUNE TKR. In 2017 a redesigned tibial baseplate (S+) was introduced, which included cement pockets and an increased surface roughness to improve cement bonding. Given the concerns of early tibial loosening with the ATTUNE knee system, this study aimed to compare revision rates and those specific to aseptic loosening of the ATTUNE implant in comparison to an established predicate as well as other implant designs used in a high-volume arthroplasty centre. Methods. The Attune TKR was introduced to our unit in December 2011. Prior to this we routinely used a predicate design with an excellent long-term track record (PFC Sigma) which remains in use. In addition, other designs were available and used as per surgeon preference. Using a prospectively maintained database, we identified 10,202 patients who underwent primary cemented TKR at our institution between 01/04/2003–31/03/2022 with a minimum of 1 year follow-up (Mean 8.4years, range 1–20years): 1) 2406 with ATTUNE TKR (of which 557 were S+) 2) 4652 with PFC TKR 3) 3154 with other cemented designs. All implants were cemented using high viscosity cement. The primary outcome measures were all-cause revision, revision for aseptic loosening, and revision for tibial loosening. Kaplan-Meier survival analysis and Cox regression models were used to compare the primary outcomes between groups. Matched cohorts were selected from the ATTUNE subsets (original and S+) and PFC groups using the nearest neighbor method for radiographic analysis. Radiographs were assessed to compare the presence of radiolucent lines in the Attune S+, standard Attune, and PFC implants. Results. At a mean of 8.4 years follow-up, 308 implants underwent revision equating to 3.58 revisions per 1000 implant-years. The lowest risk of revision was noted in the ATTUNE cohort with 2.98 per 1000-implant-years where the PFC and All Other Implant groups were 3.15 and 4.4 respectively. Aseptic loosing was the most common cause for revision across all cemented implants with 76% (65/88) of involving loosening of the tibia. Survival analysis comparing the ATTUNE cohort to the PFC and All Other Cemented Implant cohorts showed no significant differences for: all-cause revision, aseptic loosening, or tibial loosening (p=0.15,0.77,0.47). Radiolucent lines were detected in 4.6%, 5.8%, and 5.0% of the ATTUNE S+, standard ATTUNE, and PFC groups respectively. These differences were not significant. Conclusion. This study represents the largest non-registry review of the original and S+ ATTUNE TKR in comparison to its predicate design as well as other cemented implants. There appears to be no significant increased revision rate for all-cause revision or aseptic loosening. Radiographic analysis also showed no significant difference in peri-implant radiolucency. It appears that concerns of early loosening may be unfounded. Declaration of Interest. (a) fully declare any financial or other potential conflict of interest

Open tibial fractures can be difficult to manage, with a range of factors that could affect treatment and outcome. We present a large cohort of patients, and analyse which factors have significant associations with infection outcome. Elucidation will allow clinicians to strive for treatment optimisation, and patients to be advised on likely complications. Open tibia fractures treated at a major trauma centre between 2015-2021 were included. Mean age at injury was 55.4 (range 13-102). Infection status was categorized into no infection, superficial infection, and osteomyelitis. Age, mode of injury, polytrauma, fibula status, Gustilo-Anderson (GA) classification, wound contamination, time from injury to: first procedure/definitive plastics procedure/definitive fixation, type of definitive fixation, smoking and diabetic status, and BMI, were collected. Multicollinearity was calculated, with highly correlated factors removed. Multinomial logistic regression was performed. Chi Squared testing, with Post Hoc Bonferroni correction was performed for complex categorical factors. Two hundred forty-four patients with open tibial fractures were included. Forty-five developed superficial infection (18.4%), and thirty-nine developed osteomyelitis (16.0%). Polytrauma, fibula status, and type of definitive fixation were excluded from the multivariate model due to strong multicollinearity with other variables. With reference to the non-infected outcome; superficial infection patients had higher BMI (p<0.01), higher GA grade (p<0.01), osteomyelitis patients had longer time to definitive fixation (p=0.049) and time to definitive plastics procedure (p=0.013), higher GA grade (p<0.01), and positive wound contamination(p=0.015). Poc hoc analysis showed “no infection” was positively associated with GA-I (p=0.029) and GA-II (p<0.01), and negatively associated with GA-IIIC (p<0.01). Osteomyelitis was positively associated with GA-IIIc (p<0.01). This study investigated the associations between the injury and presentation factors that may affect infection outcome. The variables highlighted are the factors clinicians should give extra consideration to when treating cases, and take preventative measures to optimize treatment and mitigate infection risk

Abstract. Objectives. Epiphysiodesis is a commonly used treatment for lower limb angular deformities. However, in recent years, distal tibial growth modulation using ‘eight plates’ or screws has emerged as an alternative treatment for paediatric foot and ankle disorders, such as CTEV. Our objective was to assess the efficacy of distal tibial modulation in correcting various paediatric foot and ankle disorders. Methods. This retrospective study analysed 205 cases of paediatric foot and ankle disorders treated between 2003 and 2022, including only cases where the eight plate or screw was fixed on the anterior surface of the distal tibia. Our aim was to measure post-operative changes in dorsiflexion, the distal tibial angle, and the tibiocalcaneal angle by examining clinical records and radiology reports. Results. We identified nine cases (nine feet) meeting the full inclusion criteria, comprising seven cases of CTEV, one case of arthrogryposis, and one case of cavovarus foot. The cohort consisted of five male and four female patients, with a mean age of 10 years and 9 months at the time of surgery. Seven cases involved the left tibia, and two cases involved the right tibia. The mean time between pre-operative X-ray to surgery was 168 days, and the mean turnaround time between surgery and post-operative X-ray was 588 days. A mean change in the distal tibial angle of 4.33 degrees was noted. However, changes in dorsiflexion were documented in only one case, which showed a change of 13 degrees. Notably, our average distal tibial angle was significantly lower than reported in the literature, at 4.33 degrees. Additionally, some studies in the literature used the Oxford Ankle Foot Questionnaire for Children to assess pre- and post-operative outcomes, but it is important to note that it is validated only for children aged 5 to 16. Furthermore, most cases reported an improved tibiocalcaneal angle except for an anomaly of 105 degrees. We assessed satisfactory patient outcomes using patient notes. Out of the 6 procured notes, one has been discharged. The rest are still under yearly or 6-monthly review and are at various stages, such as physiotherapy, removing the eight plate, or requiring further surgery. The most common presentations at review are plantaris deformity and pain. Conclusions. Our study suggests that distal tibial growth modulation can be an effective treatment option for selected paediatric foot and ankle disorders. However, due to the limited number of cases in our study, the lack of documentation of changes in dorsiflexion, and a lack of pre- and post-operative outcomes using a standardised method, further research is needed to investigate this procedure's long-term outcomes and potential complications. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

The aim of this study was to perform a systematic review of the literature on Gustilo-Anderson (GA) type IIIB open tibial shaft (AO-42) injuries to determine the consistency of reporting in the literature. A search of PubMed, EMBASE and Cochrane Central Register of Controlled Trials was performed to identify relevant studies published from January 2000 to January 2021 using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. The study was registered using the PROSPERO International prospective register of systematic reviews. Patient/injury demographics, management and outcome reporting were recorded. There were 32 studies that met the inclusion criteria with a total of 1,947 patients (70.3% male, 29.7% female). There were 6 studies (18.8%) studies that reported on comorbidities and smoking, with mechanism of injury reported in 22 (68.8%). No studies reported on all operative criteria included, with only three studies (9.4%) reporting for time to antibiotics, 14 studies (43.8%) for time from injury to debridement and nine studies (28.1%) for time to definitive fixation. All studies reported on the rate of deep infection, with a high proportion documenting union rate (26/32, 81.3%). However, only two studies reported on mortality or on other post-operative complications (2/32, 6.3%). Only 12 studies (37.5%) provided any patient reported outcomes. This study has demonstrated a deficiency and a lack of standardized variable and outcome reporting in the orthopaedic literature for Gustilo-Anderson type IIIB open tibial shaft fractures. We propose a future international collaborative Delphi process is needed to standardize

Conventional proximal tibial osteotomy is a widely successful joint-preserving treatment for osteoarthritis; however, conventional procedures do not adequately control the posterior tibial slope (PTS). Alterations to PTS can affect knee instability, ligament tensioning, knee kinematics, muscle and joint contact forces as well as range of motion. This study primarily aimed to provide a comprehensive investigation of the variables influencing PTS during high tibial osteotomy using a 3D surgical simulation approach. Secondly, it aimed to provide a simple means of implementing the findings in future 3D pre-operative planning and /or clinically. The influence of two key variables: the gap opening angle and the hinge axis orientation on PTS was investigated using three independent approaches: (1) 3D computational simulation using CAD software to perform virtual osteotomy surgery and simulate the post-operative outcome. (2) Derivation of a closed-form mathematical solution using a generalised vector rotation approach (3) Clinical assessment of synthetically generated x-rays of osteoarthritis patients (n=28; REC reference: 17/HRA/0033, RD&E NHS, UK) for comparison against the theoretical/computational approaches. The results from the computational and analytical assessments agreed precisely. For three different opening angles (6°, 9° and 12°) and 7 different hinge axis orientations (from −30° to 30°), the results obtained were identical. A simple analytical solution for the change in PTS, ΔP. s,. based on the hinge axis angle, α, and the osteotomy opening angle, θ, was derived:. ΔP. s. =sin. -1. (sin α sin θ). The clinical assessment demonstrated that the absolute values of PTS, and changes resulting from various osteotomies, matched the results from the two relative prediction methods. This study has demonstrated that PTS is impacted by the hinge axis angle and the extent of the osteotomy opening angle and provided computational evidence and analytical formula for general use

Introduction and Objective. After anterior cruciate ligament reconstruction one of the risk factors for graft (re-)rupture is an increased posterior tibial slope (PTS). The current treatment for PTS is a high tibial osteotomy (HTO). This is a free-hand method, with 1 degree of tibial slope correction considered to be equal to 1 or even 1.67 mm of the anterior wedge resection. Error rates in the frontal plane reported in literature vary from 1 – 8.6 degrees, and in the sagittal plane outcomes in a range of 2 – 8 degrees are reported when planned on PTSs of 3 – 5 degrees. Therefore, the free-hand method is considered to have limited accuracy. It is expected that HTO becomes more accurate with patient specific saw guides (PSGs), with an accuracy margin reported in literature of 2 degrees. This proof of concept porcine cadaver case study aimed to investigate whether the use of PSGs improves the accuracy of HTO to less than 2 degrees. Secondly, the reproducibility of tibial slope measurement was evaluated. Materials and Methods. Preoperative MRI images of porcine cadaver knees (n = 3) were used to create 3D anatomical bone models (Mimics, Materialise, Belgium). These 3D models were subsequently used to develop PSGs (3-Matic, Materialise, Belgium) to correct all tibias for 3 degrees PTS and 4 degrees varus. The PSG mediated HTOs were performed by an experienced orthopaedic surgeon, after which postoperative MRI images were obtained. 3D anatomical models of postoperative tibias were created, and tibial slopes were assessed on both pre- and postoperative tibias. The tibial slope was defined as the angle between the mechanical axis and 3D tibial reference plane in the frontal and sagittal plane. The accuracy of the PSG mediated HTO (median and range) was defined as the difference in all possible combinations of the preoperatively planned and postoperatively obtained tibial slopes. To ensure reproducibility, the pre- and postoperative tibial slopes were measured thrice by one observer. The intra-class correlation coefficients (ICCs) were subsequently calculated to assess the intra-rater reliability (SPSS, IBM Corp., Armonk, N.Y., USA). Results. An accuracy within 2 degrees was achieved in all three cases. The median and range in accuracy for each specimen were +0.46 (−0.57 – 1.45), +0.60 (−1.07 – 1.00), and +0.45 (−0.16 – 0.71) degrees in the frontal plane, and −0.45 (−1.97 – 1.22), −0.80 (−2.42 – 1.77), and 0.00 (−2.19 – 1.93) degrees in the sagittal plane. The pre- and postoperatively planned tibial slopes in the frontal and sagittal plane were measured with a good up to excellent reproducibility. The ICCs of the preoperative planned tibial slopes were 0.82 (95% CI, 0.11 – 1.0), and 0.77 (95% CI, 0.17 – 1.0) for the frontal and sagittal plane, respectively. Postoperative, the ICC for the frontal plane was 0.92 (95% CI, 0.43 – 1.0), and 0.67 (95% CI, −0.06 – 0.99) for the sagittal plane. Conclusions. This proof of concept porcine case study showed an accuracy for the PSG mediated HTO within 2 degrees for each specimen. Moreover, the tibial slopes were measured with a good up to excellent reproducibility. Therefore, the PSG mediated HTO seems to be accurate and might be better than the current used free-hand HTO method. These results offer perspective for implementation of PSG mediated HTO to correct PTS and metaphyseal varus

Our objective was to conduct a systematic review and meta-analysis, comparing differences in clinical outcomes between either autologous or synthetic bone grafts in the operative management of tibial plateau fractures: a traumatic pattern of injury, associated with poor long-term functional prognosis. A structured search of MEDLINE, EMBASE, The Bone & Joint and CENTRAL databases from inception until 07/28/2021 was performed. Randomised, controlled, clinical trials that compared autologous and synthetic bone grafts in tibial plateau fractures were included. Preclinical studies, clinical studies in paediatric patients, pathological fractures, fracture non-union or chondral defects were excluded. Outcome data was assessed using the Risk of Bias 2 (ROB2) framework and synthesised in random-effect meta-analysis. Preferred Reported Items for Systematic Review and Meta-Analysis guidance was followed throughout. Six comparable studies involving 352 patients were identified from 3,078 records. Following ROB2 assessment, five studies (337 patients) were eligible for meta-analysis. Within these studies, more complex tibia plateau fracture patterns (Schatzker IV-VI) were predominant. Primary outcomes showed non-significant reductions in articular depression at immediate postoperative (mean difference −0.45mm, p=0.25, 95% confidence interval (95%CI): −1.21-0.31mm, I. 2. =0%) and long-term (>6 months, standard mean difference −0.56, p=0.09, 95%CI: −1.20-0.08, I. 2. =73%) follow-up in synthetic bone grafts. Secondary outcomes included mechanical alignment, limb functionality, defect site pain, occurrence of surgical site infections, secondary surgery, perioperative blood loss, and duration of surgery. Blood loss was lower (90.08ml, p<0.001, 95%CI: 41.49-138.67ml, I. 2. =0%) and surgery was shorter (16.17minutes, p=0.04, 95%CI: 0.39-31.94minutes, I. 2. =63%) in synthetic treatment groups. All other secondary measures were statistically comparable. Our findings supersede previous literature, demonstrating that synthetic bone grafts are non-inferior to autologous bone grafts, despite their perceived disadvantages (e.g. being biologically inert). In conclusion, surgeons should consider synthetic bone grafts when optimising peri-operative patient morbidity, particularly in complex tibial plateau fractures, where this work is most applicable

Introduction and Objective. The geometry of the proximal tibia and distal femur is intimately linked with the biomechanics of the knee and it is to be considered in total knee arthroplasty (TKA) component positioning. The aim of the present study was to evaluate the proximal tibial torsion in relation to the flexion-extension axis of the knee in healthy and pathological cohort affected by knee osteoarthritis (OA). Materials and Methods. We retrospectively analyzed computed tomography scans of OA knee of 59 patients prior to TKA and non-arthritic knee of 39 patients as control. Posterior condylar angle (PCA), femoral tibial torsion (TEAs-PTC and TEAs-PTT), proximal tibial torsion (PTC-PTT and PCAx-PTC) and distance between tibial tuberosity and the trochlear groove (TT-TG) were measured. Results. No differences were found for gender, age, TG-TT and PCAn angles. Statistically significant differences were found for all the other angles considered. Significant relation was found between Tibial Torsion and TEA-PTT angles, between PCAx-PTC and TEA-PTC, between TEA-PTT and TEA-PTC and between PCAx-PTC and TEA-PTT. All measures, except TG-TT and PCAn angles, showed high validity (AUC > 75%) in detecting OA, with TEA-PTT displaying the highest validity with an AUC of 94.38%. Conclusions. This is the first study to find significant differences in terms of proximal tibia geometry and anatomy between non arthritic and OA knees. It is conceivable that such anatomy could be implicated in the development of OA. Based on our data, the TEAs is a valid reference for correct positioning of tibial component in TKA. Indeed, setting the tibial component parallel to TEAs makes the prosthetic knee more similar to the native non-arthritic knee

Unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are well-established operative interventions in the treatment of knee osteoarthritis (KOA). However, which of these interventions is more beneficial, to patients with KOA, is not known and remains a topic of much debate. Aims: (i) To determine whether UKA or HTO is more beneficial in the treatment of isolated medial compartment KOA, via an assessment of patient-reported outcome measures (PROMs). (ii) To investigate the relationship between PROMs and radiographic parameters of knee joint orientation/alignment. This longitudinal observational study assessed a total of 42 patients that had undergone UKA (n=23) or HTO (n=19) to treat isolated medial compartment KOA. The PROMs assessed, pre-operatively and 1-year post-operatively, consisted of the: self-administered comorbidity questionnaire; short form-12; oxford knee score; knee injury and osteoarthritis outcome score; and the EQ-5D-5L. The radiographic parameters of knee joint alignment/orientation assessed, pre-operatively and 8-weeks post-operatively, included the: hip-knee-ankle angle; mechanical axis deviation; and the angle of the Mikulicz line. Statistical analysis demonstrated an overall significant (p<0.001), pre-operative to post-operative, improvement in the PROM scores of both groups. There were no significant differences in the post-operative PROM scores of the UKA and HTO group. Correlation analyses revealed that pre-operatively, a more distolaterally angled Mikulicz line was associated with worse knee function (p<0.05) and overall health (p<0.05); a relationship that, until now, has not been investigated nor commented upon within the literature. UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with isolated medial compartment KOA. To further the scientific/medical community's understanding of the factors that impact upon health-outcomes in KOA, future research should seek to investigate the mechanism underlying the relationship, between Mikulicz line and PROMs, observed within the current study

Medial opening wedge high tibial osteotomy (MOWHTO) is the workhorse procedure for correcting varus malalignment of the knee. There have been recent developments in the synthetic options to fill the osteotomy gap. The current gold standard for filling this osteotomy gap is autologous bone graft which is associated with donor site morbidity. We would like to introduce and describe the process of utilizing the novel Osteopore® 3D printed, honeycomb structured, Polycaprolactone and β-Tricalcium Phosphate wedge for filling the gap in MOWHTO. In the advent of additive manufacturing and the quest for more biocompatible materials, the usage of the Osteopore® bone wedge in MOWHTO is a promising technique that may improve the biomechanical stability as well the healing of the osteotomy gap

Abstract. Introduction. Long term survivorship in Total Knee Arthroplasty is significantly dependent on prosthesis alignment. The aim of this study was to determine, compare and analyse the coronal alignment of the tibial component of a single implant system using 3 different techniques. Method. Retrospective study of cases from a prospectively collected database. Radiological assessment included measurement of the coronal alignment of tibial components of total knee arthroplasties, and its deviation from the mechanical axis. A comparison study of intramedullary, extramedullary and tibial crest alignment methods was performed. Results. 66 consecutive patients (3 groups of 22 each). Mean BMI was 26. The mean angle of deviation from the mechanical axis was significantly lesser (p< 0.05) in the Tibial crest alignment group patients compared to the other 2 groups. Moreover, the number of outliers (+/-3 degrees) were 2 and 4 in the intra and extramedullary group, whereas there were none in the tibial crest group. The inter and intraclass correlation coefficient was 0.8 and 0.9 respectively. Conclusion. The Tibial Crest Alignment Technique is an effective technique to produce consistent results to achieve optimal coronal alignment of the tibial component in TKA, even in patients with high BMI. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Healing after bone fracture is assessed by frequent radiographs, which expose patients to radiation and lacks behind biological healing. This study aimed to investigate whether the electrical impedance using electrical impedance spectroscopy correlated to quantitative scores of bone healing obtained from micro-CT and mechanical bending test. Eighteen rabbits were subjected to tibial fracture that was stabilized with external fixator. Two electrodes were positioned, one electrode placed within the medullary cavity and the other on the lateral cortex, both three millimeters from the fracture site. Impedance was measured daily across the fracture site at a frequency range of 5 Hz to 1 MHz. The animals were divided into three groups with different follow-up time: 1, 3 and 6 weeks for micro-CT (Bone volume/tissue volume (BV/TV, %)) and mechanical testing (maximum stress (MPa), failure energy (kJ/cm3), young modulus (Mpa)). There was a statistically significant correlation between last measured impedance at 5 Hz frequency immediately prior to euthanasia and BV/TV of callus (−0.68, 95%CI: (−0.87; −0.31)). Considering the mechanical testing with three-point bending, no significant correlation was found between last measured impedance at 5 Hz frequency immediately prior to euthanasia and maximum stress (−0.35, 95%CI: (−0.70; 0.14)), failure energy (−0.23, 95%CI: (−0.63; 0.26)), or young modulus (−0.28, 95%CI: (−0.66; 0.22)). The significant negative correlation between impedance and BV/TV might indicate that impedances correlate with the relative bone volume in the callus site. The lack of correlation between impedance and mechanical parameters when at the same time observing a correlation between impedance and days since operation (0-42 days), might indicate that the impedance can measure biological changes at an earlier time point than rough mechanical testing

Aim. To investigate the effect of the eight plate position in sagittal plane on tibial slope in temporary epiphysiodesis technique applied to the proximal tibia and whether there is a rebound effect after removing the plate. Method. Forty New Zealand rabbits (6 weeks old) were divided into four groups. In all groups, two 1.3 mm mini plates and cortical screws implantation were placed on both medial and lateral side of the proximal epiphysis of the right tibia. In Group 1 and 3, the plates were placed on anterior of the proximal tibial anatomical axis in the sagittal plane, and placed posteriorly in Group 2 and 4. The left tibia was examined as control in all groups. Group 1 and Group 2 were sacrificed after four week-follow-up. In Group 3 and Group 4, the implants were removed four weeks after index surgery and the rabbits were followed four more weeks to investigate the rebound effect. The tibial slope was measured on lateral X-rays every two weeks. Both medial and lateral plateau slopes were evaluated on photos of the dissected tibia. Results. In Group 1, right MTPA (medial tibial plateau angle) and left MTPA, right LTPA (lateral tibial plateau angle) and left LTPA, and right 4wTPPA (the tibial proximal posterior angle at 4th week) and left 4wTPPA values were compared with each other. There was a significant difference in MTPA, LTPA, and 4wTPPA in Group 1 (p: 0.003, 0.006, 0.004). In Group 1, the medial and lateral slope significantly decreased after 4 weeks. There was no significant difference in MTPA, LTP and 4wTPPA measurements in Group 2 (p= 0.719, 0.306, 0.446, respectively). In Group 2, the slope did not change in four weeks. There was a significant difference in MTPA, LTPA, 4wTPPA, and 8wTPPA (tibial proximal posterior angle at 8th week) in Group 3 (p= 0.005, 0.002, <0.001, <0.001, respectively). In Group 3, the slope decreased at 4th week and remained stabile during the next four week-follow up and no rebound effect was observed. There was no significant difference in MTPA, LTPA, 4wTPPA, and 8wTPPA measurements in Group 4 (p= 0.791, 0.116, 0.232, 0.924), respectively. In group 4, slope did not change at 4th week of index surgery and no rebound effect was observed in the next four week-follow up. Conclusion. If eight plates were placed on anterior of lateral proximal tibia axis on both medial and lateral side, the tibial slope would reduce, and remain stabile after implant removal. Care should be taken to place the plates on the line of proximal tibial axis in sagittal plane in temporary epiphysiodesis technique performed due to angular knee deformities. Changing the slope due to plate placement can be used as a secondary gain for patients who will benefit from slope change, such as adolescent ACL surgery