Abstract. Background. With the increasingly accepted method of suprapatellar tibial nailing for tibial shaft fractures, we aimed to compare intraoperative and postoperative outcomes of infrapatellar (IP) vs suprapatellar (SP) tibial nails. Methods. A retrospective cohort analysis of 58 patients. 34 SP tibial nails over 3 years versus 24 IP tibial nails over a similar time frame. We compared; radiation exposure, patient positioning time (PPT), non-union rate and follow-up time. Knee pain in the SP group was evaluated, utilising the Hospital for Special Surgery (HSS) Knee injury and Osteoarthritis outcome score (KOOS). Results. 58 patients with a mean age of 43 years were included. Mean intraoperative radiation dose for SP nails was 61.78cGy (range 11.60 to 156.01cGy) vs 121.09cGy (range 58.01 to 18.03cGy) for IP nails (p < 0.05). Mean PPT for SP nails was 10 minutes vs 18 minutes for IP nails (p < 0.05). All fractures united in the SP group vs one non-union in the IP group. Mean follow-up was 5.5 months vs 11 months in the SP and IP group respectively. Mean KOOS was 7 (range 0 to 22) at 6 months for the SP group. Conclusion. The semi extended position (SP group) leads to reduced radiation exposure because of ease of imaging. All Patients in the SP group showed improved outcomes, with shorter follow-up and fracture union. The KOOS revealed SP nail patients had minimal pain and good knee function. This study establishes a management and PROMs baseline for ongoing evaluation of SP nails

Introduction. Diaphyseal tibial fractures account for approximately 1.9% of adult fractures. Several studies demonstrate a high proportion of diaphyseal tibial fractures have ipsilateral occult posterior malleolus fractures, this ranges from 22–92.3%. Materials and Methods. A retrospective review of a prospectively collected database was performed at Liverpool University Hospitals NHS Foundation Trust between 1/1/2013 and 9/11/2020. The inclusion criteria were patients over 16, with a diaphyseal tibial fracture and who underwent a CT. The articular fracture extension was categorised into either posterior malleolar (PM) or other fracture. Results. 764 fractures were analysed, 300 had a CT. There were 127 intra-articular fractures. 83 (65.4%) cases were PM and 44 were other fractures. On univariate analysis for PM fractures, fibular spiral (p=.016) fractures, no fibular fracture(p=.003), lateral direction of the tibial fracture (p=.04), female gender (p=.002), AO 42B1 (p=.033) and an increasing angle of tibial fracture. On multivariate regression analysis a high angle of tibia fracture was significant. Other fracture extensions were associated with no fibular fracture (p=.002), medial direction of tibia fracture (p=.004), female gender (p=.000), and AO 42A1 (p=.004), 42A2 (p=.029), 42B3 (p=.035) and 42C2 (p=.032). On multivariate analysis, the lateral direction of tibia fracture, and AO classification 42A1 and 42A2 were significant. Conclusions. Articular extension happened in 42.3%. A number of factors were associated with the extension, however multivariate analysis did not create a suitable prediction model. Nevertheless, rotational tibia fractures with a high angle of fracture should have further investigation with a CT

The optimal method of tibial fixation when using a hamstring tendon autograft in anterior cruciate ligament (ACL) reconstruction is unclear. This study aimed to compare the risk of revision ACL reconstruction between suspensory and interference devices on the tibial side. Prospective data on primary ACL reconstructions recorded in the New Zealand ACL Registry between April 2014 and December 2019 were analyzed. Only patients with a hamstring tendon autograft fixed with a suspensory device on the femoral side were included. The rate of revision ACL reconstruction was compared between suspensory and interference devices on the tibial side. Univariate Chi-Square test and multivariate Cox regression was performed to compute hazard ratios (HR) and 95% confidence intervals (CI) with adjustment for age, gender, time-to-surgery, activity at the time of injury, number of graft strands and graft diameter. 6145 cases were analyzed, of which 59.6% were fixed with a suspensory device on the tibial side (n = 3662), 17.6% fixed with an interference screw with a sheath (n = 1079) and 22.8% fixed with an interference screw without a sheath (n = 1404). When compared to suspensory devices (revision rate = 3.4%), a higher risk of revision was observed when using an interference screw with a sheath (revision rate = 6.2%, adjusted HR = 2.05, 95% CI 1.20 – 3.52, p = 0.009) and without a sheath (revision rate = 4.6%, adjusted HR = 1.81, 95% CI 1.02 – 3.23, p = 0.044). The number of graft strands and a graft diameter of ≥8 mm did not influence the risk of revision. When reconstructing the ACL with a hamstring tendon autograft, the use of an interference screw, with or without a sheath, on the tibial side has a higher risk of revision when compared to a suspensory device

Aims. As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach. Methods. A total of 58 patients (median age 17 years (interquartile range (IQR) 15 to 21)) treated by unilateral tibial distraction osteogenesis for a median leg length discrepancy of 41 mm (IQR 34 to 53), and nine patients with disproportionate short stature treated by bilateral simultaneous tibial distraction osteogenesis, with magnetically controlled motorized ILNs inserted via an antegrade approach, were retrospectively analyzed. The median follow-up was 37 months (IQR 30 to 51). Outcome measurements were accuracy, precision, reliability, bone healing, complications, and patient-reported outcome assessed by the Limb Deformity-Scoliosis Research Society Score (LD-SRS-30). Results. A median tibial distraction of 44 mm (IQR 31 to 49) was achieved with a mean distraction index of 0.5 mm/day (standard deviation 0.13) and median consolidation index of 41.2 days/cm (IQR 34 to 51). Accuracy, precision, and reliability were 91%, 92%, and 97%, respectively. New temporary range of motion limitations occurred in 51% of segments (34/67). Distraction-related equinus deformity treated by Achilles tendon lengthening was the most common major complication recorded in 16% of segments (11/67). In 95% of patients (55/58) the distraction goal was achieved with 42% unplanned additional interventions per segment (28/67). The median postoperative LD-SRS-30 score was 4.0 (IQR 3.6 to 4.3). Conclusion. Tibial distraction osteogenesis using motorized ILNs inserted via an antegrade approach appears to be a reliable and precise procedure. Temporary joint stiffness of the knee or ankle should be expected in up to every second patient. A high rate and wide range of complications of variable severity should be anticipated. Cite this article: Bone Joint J 2024;106-B(3):293–302

Background. Cementless Total Knee Arthroplasty has been developed to reduce the incidence of failure secondary to aseptic loosening, osteolysis and stress-induced osteopenia, especially in younger and more active patients. However, failures are still more common compared to cemented components, especially those involving the tibia. It is hypothesized that this is caused by incomplete contact between the tibial tray and the underlying bony surface due to: (i) inadequate flatness of the tibial osteotomy, or (ii) failure of implantation to spread the area of contact over the exposed cancellous surface. In the present study we compare the contact area developed during implantation of a cementless tray as a function of the initial flatness of the tibial osteotomy. Method. Eight joint replacement surgeons prepared 14 cadaveric knees for cementless TKR using a standard instrumentation set (ZimmerBiomet Inc). The tibial osteotomy was created using an oscillating bone saw and a 1.27mm blade (Stryker Inc) directed by a slotted cutting guide mounted on an extramedullary rod and fixed to the tibia with pins and screws. The topography of the exposed cancellous surface was captured with a commercial laser scanner (Faro Inc, Halifax, approx. 33,000 surface points). 3D computer models of each tibial surface were generated in a CAD environment (Rapidform, Inuus). After scanning, a cementless tibial tray was implanted on the prepared tibial surface using a manual impactor. The tray-tibia constructs were dissected free of soft tissue, embedded in mounting resin, and sectioned with a diamond wafering saw. Points of bone-tray contact and interface separation were identified by stereomicroscopy and incorporated in the 3D computer models. Maps were generated depicting contacting and non-contacting areas Each model was subdivided into 7 zones for characterizing the distribution of interface contact in terms of anatomic location. Results. The flatness for the tibial osteotomies averaged 1.1±0.35 mm (range: 0.56–1.81mm). After impaction, 79.8±0.3% of the tibial surface had plastically deformed to establish a contacting interface with the implant. 15.1% of the bony surface was within 0.2mm of the tray and 17.6% was within 0.3mm. Gaps large enough to impede ingrowth only occupied 2.6% of the exposed tibial These non-contacting areas were typically located centrally at the ACL, PCL and canal zones. There was an inverse linear relationship between the initial flatness of the tibial osteotomy and the percentage of tray-bone contact. Conclusions. The amount of direct contact between the bone and implant is critical for the development of stability in cementless fixation. We found a relationship between ultimate bony contact and initial flatness. However, we also found that during impaction of the implant, bony contact increased through deformation of the most prominent peaks of the cancellous surface. Interface gaps were consistently observed in central areas of the tibia surface located above the medullary canal which may be reduced through selection of trays with distal keels. For any figures or tables, please contact authors directly

Classification systems for tibial plateau fractures suffer from poor interobserver agreement, and their value in preoperative assessment to guide surgical fixation strategies is limited. For tibial plateau fractures four major characteristics are identified: lateral split fragment, posteromedial fragment, anterior tubercle fragment, and central zone of comminution. These fracture characteristics support preoperative assessment of fractures and guide surgical decision-making as each specific component requires a respective fixation strategy. We aimed to evaluate the additional value of 3D-printed models for the identification of tibial plateau fracture characteristics in terms of the interobserver agreement on different fracture characteristics. Preoperative images of 40 patients were randomly selected. Nine trauma surgeons, eight senior and eight junior registrars indicated the presence or absence of four fracture characteristics with and without 3D-printed models. The Fleiss kappa was used to determine interobserver agreement for fracture classification and for interpretation, the Landis and Koch criteria were used. 3D-printed models lead to a categorical improvement in interobserver agreement for three of four fracture characteristics: lateral split (Kconv = 0.445 versus K3Dprint = 0.620; P < 0.001), anterior tubercle fragment (Kconv = 0.288 versus K3Dprint = 0.449; P < 0.001) and zone of comminution (Kconv = 0.535 versus K3Dprint = 0.652; P < 0.001). The overall interobserver agreement improved for three of four fracture characteristics after the addition of 3D printed models. For two fracture characteristics, lateral split and zone of comminution, a substantial interobserver agreement was achieved. Fracture characteristics seem to be a more reliable way to assess tibial plateau fractures and one should consider including these in the preoperative assessment of tibial plateau fractures compared to the commonly used classification systems

Aim. To report outcomes of soft tissue reconstruction using free tissue transfer for the treatment of tibial osteomyelitis as part of a single-stage, ortho-plastic procedure. Method. Patients who underwent ortho-plastic reconstructive surgery to excise tibial osteomyelitis in combination with free tissue transfer in one stage were included. Patients underwent surgery between 2015 and 2024 in a single specialist centre within the UK. Baseline patient information, demographics, and infection information was recorded. Adverse outcomes were defined as (i) flap salvage required, (ii) flap failure and (iii) recurrence of infection. Patient reported quality of life was measured using the EuroQol EQ-5D-5L index score. Pre-operative QoL was compared to QoL at 1 year with a control group of 53 similar patients who underwent surgical treatment for tibial osteomyelitis without a free flap (local flap or primary closure). Results. Ninety-three patients were eligible for inclusion, with a mean age of 52 years (range 18–90). 77/93 (82.8%) had a free muscle flap with the remainder (17.2%) receiving a fasciocutaneous flap. The donor tissue was defined as 57 gracilis, 6 latissimus dorsi, 14 hemi-latissimus dorsi, and 16 anterolateral thigh. The recipient area of the tibia was distal 1/3 in 52 cases, middle 1/3 in 27 cases and proximal 1/3 in 12 cases. The average flap ischaemic time was 70 minutes (range 28 to 125). Seven patients (7.5%) required urgent flap salvage at a median time of 1.0 day (range 0.5 – 4.0). Of these, 4 (4.3%) went on to have total flap failure, of which 2 patients underwent below knee amputation subsequently. Flap failure was due to either arterial (n=2) or venous (n=2) anastomotic thrombus. There were 3 (3.2%) episodes of confirmed infection recurrence within the first year after the index procedure. EQ-index scores at 1-year post-operatively were significantly improved when compared to pre-operative scores (p=0.008). At 1-year post-operatively, EQ-index scores in patients who underwent free flap was similar compared to local flaps (p=0.410) and in those who underwent primary closure for tibial osteomyelitis (p=0.070). Conclusions. Microsurgical single stage surgery can achieve high flap survival rate (95.7%). Free flaps fail early due to anastomotic thrombus with no late failures seen. Free tissue transfer does not appear to give inferior QoL compared to matched patients with local flaps or direct closure in tibial osteomyelitis

This study aimed to examine the effect of high tibial osteotomy (HTO) on the ankle and subtalar joints via analysis of static radiographic alignment. We hypothesised that surgical alteration of the alignment of the proximal tibia would result in compensatory distal changes. 35 patients recruited as part of the wider Biomechanics and Bioengineering Centre Versus Arthritis HTO study between 2011 and 2018 had pre- and postoperative full-length weightbearing radiographs taken of their lower limbs. In addition to standard alignment measures of the limb and knee (mechanical tibiofemoral angle, Mikulicz point, medial proximal tibial angle), additional measures were taken of the ankle/subtalar joints (lateral distal tibial angle, ground-talus angle, joint line convergence angle of the ankle) as well as a novel measure of stance width. Results were compared using a paired T-test and Pearson's correlation coefficient. Following HTO, there was a significant (5.4°) change in subtalar alignment. Ground-talus angle appeared related both to the level of malalignment preoperatively and the magnitude of the alignment change caused by the HTO surgery; suggesting subtalar positioning as a key adaptive mechanism. In addition to compensatory changes within the subtalar joints, the patients on average had a 31% wider stance following HTO. These two mechanisms do not appear to be correlated but the morphology of the tibial plafond may influence which compensatory mechanisms are employed by different subgroups of HTO patients. These findings are of vital importance in clinical practice both to anticipate potential changes to the ankle and subtalar joints following HTO but it could also open up wider indications for HTO in the treatment of ankle malalignment and osteoarthritis

This study investigated concurrent talar dome injuries associated with tibial pilon fractures, mapping their distribution across the proximal talar dome articular surface. It compared the two main mechanisms of injury (MOI), falling from a height and motor vehicle accident (MVA), and whether the fractures were open or closed. From a previously compiled database of acute distal tibial pilon fractures (AO/OTA 43B/C) in adults of 105 cases, 53 cases were identified with a concurrent injury to the talar dome with a known mechanism of injury and in 44 it was known if the fracture was open or closed. Case specific 2D injury maps were created using a 1x1mm grid, which were overlayed in an Excel document to allow for comparative analyses. A two-way ANOVA was conducted that examined the effect of both MOI and if the fracture was open or closed on what percentage of the talar dome surface was injured. There was a statistically-significant difference between the average percentage of injured squares on the talar dome by both whether the fracture was open or closed (f(1)=5.27, p= .027) and the mechanism of injury (f(1)=8.08, p= .007), though the interaction between these was not significant (p= .156). Open injuries and injuries that occurred during an MVA were more likely to increase the surface area of the talar dome injuries. We have identified both MOI and if the fracture was either open or closed impacts the size of the injury present on the talar dome. Future research will investigate the aetiology of the differences noted, highlighting the clinical implications. Surgeons treating tibial pilon fractures caused by either a MVA or an open fracture, should be aware of an increased risk of large injuries to the surface of the talar dome

Little information exists regarding optimal tibial stem usage in revision total knee arthroplasty (rTKA) utilising a tibial trabecular metal (TM) cone. The purpose of this study was to compare 1) functional outcomes, 2) radiographic outcomes, and 3) implant survivorship in rTKA utilising TM cones combined with either short stems (SS) or long stems (LS) at minimum two-years clinical follow-up. In this retrospective, multi-centre study, patients undergoing TM cone utilising rTKA between 2008 and 2019 were included. Patients were divided into: SS group (no diaphyseal engagement), and LS group (diaphyseal engagement). All relevant clinical charts and post-operative radiographs were examined. Oxford Knee Score (OKS) and EuroQol-5D (EQ-5D-5L) data were collected at most recent follow-up. In total, 44 patients were included: 18 in the SS group and 26 in the LS group. The mean time of follow-up was 4.0 years. Failure free survival was 94.5% for the SS group and 92.3% for the LS group. All failures were for prosthetic joint infections managed with debridement, antibiotics, and implant retention. At most recent follow-up, 3 patients demonstrated radiographic signs of lucency (1 SS 2 LS, p = 1) and the mean OKS were 37 ± 4 and 36 ± 6 (p = 0.73) in the SS and LS groups, respectively. Tibial SS combined with TM cones performed as well as LS in rTKA at minimum two-years follow-up. A tibial SS in combination with a TM cone is a reliable technique to achieve stable and durable fixation in rTKA

Tibial plateau fracture reduction involves restoration of alignment and articular congruity. Restorations of sagittal alignment (tibial slope) of medial and lateral condyles of the tibial plateau are independent of each other in the fracture setting. Limited independent assessment of medial and lateral tibial plateau sagittal alignment has been performed to date. Our objective was to characterize medial and lateral tibial slopes using fluoroscopy and to correlate X-ray and CT findings. Phase One: Eight cadaveric knees were mounted in extension. C-arm fluoroscopy was used to acquire an AP image and the C-arm was adjusted in the sagittal plane from 15° of cephalad tilt to 15 ° of caudad tilt with images captured at 0.5° increments. The “perfect AP” angle, defined as the angle that most accurately profiled the articular surface, was determined for medial and lateral condyles of each tibia by five surgeons. Given that it was agreed across surgeons that more than one angle provided an adequate profile of each compartment, a range of AP angles corresponding to adequate images was recorded. Phase Two: Perfect AP angles from Phase One were projected onto sagittal CT images in Horos software in the mid-medial compartment and mid-lateral compartment to determine the precise tangent subchondral anatomic structures seen on CT to serve as dominant bony landmarks in a protocol generated for calculating medial and lateral tibial slopes on CT. Phase Three: 46 additional cadaveric knees were imaged with CT. Tibial slopes were determined in all 54 specimens. Phase One: Based on the perfect AP angle on X-ray, the mean medial slope was 4.2°+/-2.6° posterior and mean lateral slope was 5.0°+/-3.8° posterior in eight knees. A range of AP angles was noted to adequately profile each compartment in all specimens and was noted to be wider in the lateral (3.9°+/-3.8°) than medial compartment (1.8°+/-0.7° p=0.002). Phase Two: In plateaus with a concave shape, the perfect AP angle on X-ray corresponded with a line between the superiormost edges of the anterior and posterior lips of the plateau on CT. In plateaus with a flat or convex shape, the perfect AP angle aligned with a tangent to the subchondral surface extending from center to posterior plateau on CT. Phase Three: Based on the CT protocol created in Phase Two, mean medial slope (5.2°+/-2.3° posterior) was significantly less than lateral slope (7.5°+/-3.0° posterior) in 54 knees (p<0.001). In individual specimens, the difference between medial and lateral slopes was variable, ranging from 6.8° more laterally to 3.1° more medially. In a paired comparison of right and left knees from the same cadaver, no differences were noted between sides (medial p=0.43; lateral p=0.62). On average there is slightly more tibial slope in the lateral plateau than medial plateau (2° greater). However, individual patients may have substantially more lateral slope (up to 6.8°) or even more medial slope (up to 3.1°). Since tibial slope was similar between contralateral limbs, evaluating slope on the uninjured side provides a template for sagittal plane reduction of tibial plateau fractures

Introduction. Design evolution of total knee arthroplasty (TKA) has improved implant durability and clinical outcomes. However, it has been reported that some patients have limited satisfaction with their operated knees [1]. In view of better patient satisfaction, there have been growing interests in anatomically aligned TKA. The anatomically aligned TKA technique aims to replicate natural joint line of the patients [2][3]. However, restoration of natural joint line may be difficult for the knees with severe deformity, as their joint alignment with respect to bony landmarks at a time of surgery may be critically different from their pre-diseased state. The purpose of this study is to investigate alignment of the tibial growth plate with respect to tibial anatomical landmarks for possible application in estimation of pre-diseased joint alignment. Methods. Three-dimensional tibial models were created from CT scans of 22 healthy Japanese knees (M7:F15, Age 31.0±12.6 years) using Mimics (Materialise NV, Leuven, Belgium). The mid-sagittal plane of the tibia was defined by medial margin of the tibial tuberosity, origin of the PCL and center of the foot joint. The tibial plateau (or joint line plane) was determined by following three points; a dwell point of aligned femur on lateral tibial articular surface, and two points at anterior and posterior rim of medial tibial articular surface defined within sagittal plane that coincide with dwell point of femur on medial tibia. All measurements were made with respect to the mid-sagittal plane. The shape of the tibial growth plate (GP) was extracted using Livewire function and mask editing tools of Mimics. To determine 3D orientation of the GP, moment of inertia axes were calculated for the 3D model. The inertia axes were also determined for medial and lateral half of the GP (Figure 1). Results. Tibial plateau (TP) had 2.38±1.78 degrees of varus and 11.37±3.76 degrees of posterior inclination. In coronal view, the GP axis was in varus alignment to the normal axis of the TP by 3.29±1.45 degrees. The shape of the GP is found to be different for medial and lateral half. The posterior inclination of the medial half tends to follow the TP, while the lateral half is twisted anteriorly (Figure 2). The GP medial half was in 5.03±2.89 degrees valgus and 1.62±2.37 degrees anteriorly inclined relative to the TP. The GP lateral half was in 10.38±2.62 degrees varus and 18.11±3.79 degrees anteriorly inclined relative to the TP. Discussion. The results from 22 healthy knees suggested that the tibial growth plate is aligned to tibial plateau in varus orientations with relatively small deviations. Distinctive shape difference for medial and lateral half of the growth plate was also observed. Limitation of this study is a number of subjects available for the analysis. Future study should consider inclusion of arthritic knees with various levels of deformities. For figures/tables, please contact authors directly.

Introduction. The use of the Taylor Spatial Frame (TSF) in the management of tibial fractures and deformity correction is well established in the literature, however the majority of published papers are small in patient number. The aim of the project was to evaluate clinical and radiographic outcomes of patients with tibial fractures treated with a TSF. Materials and Methods. A retrospective analysis of patient records and radiographs was performed to obtain patient data, information on injury sustained, the operative technique used, frame construct, time duration in frame, union rates and complications of treatment. Results. In total, 111 tibial fractures managed with a TSF between 2009 and 2020 were reviewed. 55 were open fractures and 56 were closed. Overall union rate was 93.5%. Average time spent in the frame was 27.9 weeks. Complications included 4.6% deep infection rate, 3.7% of patients required component exchange and 8.3% required frame adjustment in theatre. Conclusions. The TSF is an effective way of managing tibial fractures. Our data has found high union rates when used in the management of both closed and open injuries with a low complication rate. Further data collection and analysis will help to aid the patient experience and clinical practice

Purpose. Medial tibial condylar fractures (MTCFs) are rare but a serious complication after unicompartmental knee arthroplasty (UKA). The reasons for MTCFs was thought to be associated with the surgical procedures that are the halls for the guide pins, extended cut of the posterior tibial cortex, an incorrect positioning of the tibial keel groove, and an excessive force application when placing the tibial component. However, the relationship between MTCFs and the alignment of the tibial component has not been proven. The purpose of the study was to investigate the effect of the tibial component alignment to the MTCFs using the finite element method (FEM). Materials and Methods. We used three-dimensional (3D) image model of the tibia (Sawbones: Washington, US) on the FEM analysis software (ANSYS Design Space ver. 12, Tokyo, Japan). We measured the bone stresses in the 3D image model of the tibia at the site of the medial metaphyseal cortex and the anterior/posterior cortex. The tibial component was placed 0°, 3°varus, 3°valgus, 6°varus, and 6° valgus relative to the tibial anatomical axis in the coronal plane (Figure 1). In sagittal plane, tibial component was positioned 7° posterior inclination relative to the tibial anatomical axis. And, making an additional vertical groove at the posterior cortex by the extended sagittal saw cut of 2° and 10° posterior inclination, the impact of posterior cortical bone stress was evaluated (Figure 2). A load of 900 N was applied to the center of the tibial component parallel to the tibial axis, the maximum bone stress was subsequently calculated. Furthermore, to evaluate the stress distribution, we calculated the bone mass of the 3D bone model below the tibia component under the various alignment of the tibial component (Figure 3). Results. The bone stress at the medial metaphyseal cortex and the anterior cortex did not change depending on the alignment of the tibial component (Figure 4). When the tibial component was placed varus, the bone stress at the posteiror cortex decreased. By contrast, the valgus position of the tibial component increased the bone stress. An extended sagittal saw cut increased the bone stress depending on the depth of the groove. The bone mass of the tibia below the tibial component decreased as positioning the tibial component valgus. Conclusions. Surgeons should be aware of the potential pitfalls of valgus alignemnt of the tibial component and an extended sagittal saw cut, because this can lead to increased risk of the MTCFs

Introduction. A significant burden of disease exists with respect to critical sized bone defects; outcomes are unpredictable and often poor. There is no absolute agreement on what constitutes a “critically-sized” bone defect however it is widely considered as one that would not heal spontaneously despite surgical stabilisation, thus requiring re-operation. The aetiology of such defects is varied. High-energy trauma with soft tissue loss and periosteal stripping, bone infection and tumour resection all require extensive debridement and the critical-sized defects generated require careful consideration and strategic management. Current management practice of these defects lacks consensus. Existing literature tells us that tibial defects 25mm or great have a poor natural history; however, there is no universally agreed management strategy and there remains a significant evidence gap. Drawing its origins from musculoskeletal oncology, the Capanna technique describes a hybrid mode of reconstruction. Mass allograft is combined with a vascularised fibula autograft, allowing the patient to benefit from the favourable characteristics of two popular reconstruction techniques. Allograft confers initial mechanical stability with autograft contributing osteogenic, inductive and conductive capacity to encourage union. Secondarily its inherent vascularity affords the construct the ability to withstand deleterious effects of stressors such as infection that may threaten union. The strengths of this hybrid construct we believe can be used within the context of critical-sized bone defects within tibial trauma to the same success as seen within tumour reconstruction. Methodology. Utilising the Capanna technique in trauma requires modification to the original procedure. In tumour surgery pre-operative cross-sectional imaging is a pre-requisite. This allows surgeons to assess margins, plan resections and order allograft to match the defect. In trauma this is not possible. We therefore propose a two-stage approach to address critical-sized tibial defects in open fractures. After initial debridement, external fixation and soft tissue management via a combined orthoplastics approach, CT imaging is performed to assess the defect geometry, with a polymethylmethacrylate (PMMA) spacer placed at index procedure to maintain soft tissue tension, alignment and deliver local antibiotics. Once comfortable that no further debridement is required and the risk of infection is appropriate then 3D printing technology can be used to mill custom jigs. Appropriate tibial allograft is ordered based on CT measurements. A pedicled fibula graft is raised through a lateral approach. The peroneal vessels are mobilised to the tibioperoneal trunk and passed medially into the bone void. The cadaveric bone is prepared using the custom jig on the back table and posterolateral troughs made to allow insertion of the fibula, permitting some hypertrophic expansion. A separate medial incision allows attachment of the custom jig to host tibia allowing for reciprocal cuts to match the allograft. The fibula is implanted into the allograft, ensuring nil tension on the pedicle and, after docking the graft, the hybrid construct is secured with multi-planar locking plates to provide rotational stability. The medial window allows plate placement safely away from the vascular pedicle. Results. We present a 50-year-old healthy male with a Gustilo & Anderson 3B proximal tibial fracture, open posteromedially with associated shear fragment, treated using the Capanna technique. Presenting following a fall climbing additional injuries included a closed ipsilateral calcaneal and medial malleolar fracture, both treated operatively. Our patient underwent reconstruction of his tibia with the above staged technique. Two debridements were carried out due to a 48-hour delay in presentation due to remote geographical location of recovery. Debridements were carried out in accordance with BOAST guidelines; a spanning knee external fixator applied and a small area of skin loss on the proximal medial calf reconstructed with a split thickness skin graft. A revision cement spacer was inserted into the metaphyseal defect measuring 84mm. At definitive surgery the external fixator was removed and graft fixation was extended to include the intra-articular fragments. No intra-operative complications were encountered during surgeries. The patient returned to theatre on day 13 with a medial sided haematoma. 20ml of haemoserous fluid was evacuated, a DAIR procedure performed and antibiotic-loaded bioceramics applied locally. Samples grew Staphylococcus aureus and antibiotic treatment was rationalised to Co-Trimoxazole 960mg BD and Rifampicin 450mg BD. The patient has completed a six-week course of Rifampicin and continues on suppressive Co-Trimoxazole monotherapy until planned metalwork removal. There is no evidence of ongoing active infection and radiological evidence of early union. The patient is independently walking four miles to the gym daily and we believe, thus far, despite accepted complications, we have demonstrated a relative early success. Conclusions. A variety of techniques exist for the management of critical-sized bone defects within the tibia. All of these come with a variety of drawbacks and limitations. Whilst acceptance of a limb length discrepancy is one option, intercalary defects of greater than 5 to 7cm typically require reconstruction. In patients in whom fine wire fixators and distraction osteogenesis are deemed inappropriate, or are unwilling to tolerate the frequent re-operations and potential donor site morbidity of the Masqualet technique, the Capanna technique offers a novel solution. Through using tibial allograft to address the size mismatch between vascularised fibula and tibia, the possible complication of fatigue fracture of an isolated fibula autograft is potentially avoidable in patients who have high functional demands. The Capanna technique has demonstrated satisfactory results within tumour reconstruction. Papers report that by combining the structural strength of allograft with the osteoconductive and osteoinductive properties of a vascularised autograft that limb salvage rates of greater than 80% and union rates of greater than 90% are achievable. If these results can indeed be replicated in the management of critical-sized bone defects in tibial trauma we potentially have a treatment strategy that can excel over the more widely practiced current techniques

Introduction. Computer hexapod assisted orthopaedic surgery (CHAOS) has previously been shown to provide a predictable and safe method for correcting multiplanar femoral deformity. We report the outcomes of tibial deformity correction using CHAOS, as well as a new cohort of femoral CHAOS procedures. Materials and Methods. Retrospective review of medical records and radiographs for patients who underwent CHAOS for lower limb deformity at our tertiary centre between 2012–2020. Results. There were 70 consecutive cases from 56 patients with no loss to follow-up. Mean age was 40 years (17 to 77); 59% male. There were 48 femoral and 22 tibial procedures. Method of fixation was intramedullary nailing in 47 cases and locking plates in 23. Multiplanar correction was required in 43 cases. The largest correction of rotation was 40 degrees, and angulation was 28 degrees. Mean mechanical axis deviation reduction per procedure was 17.2 mm, maximum 89 mm. Deformity correction was mechanically satisfactory in all patients bar one who was under-corrected, requiring revision. Complications from femoral surgery included one under-correction, two cases of non-union, and one pulmonary embolism. Complications from tibial surgery were one locking plate fatigue failure, one compartment syndrome, one pseudoaneurysm of the anterior tibial artery requiring stenting, and one transient neurapraxia of the common peroneal nerve. There were no deaths. Conclusions. CHAOS can be used for reliable correction of complex deformities of both the femur and tibia. The risk profile appears to differ between femoral and tibial surgeries

Background. Several studies have reported that tibial component in varus alignment can worsen the survivorship of medial unicompartmental knee arthroplasty (UKA). On the other hand, Varus/valgus inclination of the tibial component can affect the location of the contact point between femoral and tibial component especially in round on flat bearing surface design. Along with the tibial component inclination, changes in the contact point may also alter the tibial condylar bone stress, which would affect the longevity or complications after UKA. Method. We constructed a validated three-dimensional finite element model of the tibia with a medial component and assessed stress concentrations by changing the tibial component coronal inclinations (squale inclination, 3° and 6° varus, 3° and 6° valgus inclination). We evaluated the Von Mises stress on the medial tibial metaphyseal cortex and the proximal resected surface when a load of 900N was applied on the tibial component surface by two conditions in each inclination models; one is that the loading site is fixed at the mediolateral center of the tibial component (fixed model), and the other is that the loading site is variable depending on the tibial component inclination (variable model) (Fig.1). Result. In variable models, the loading site moved medially 22.8% of the tibial component width as the tibial component inclination changed from 6°varus to 6°valgus. The Von Mises stress concentrations were observed on the medial tibial metaphyseal cortices and on the anterior and posterior corner of the resected surface in all models (Fig.2). Stress concentration was also observed along the medial cortical rim of the resected surface in valgus tibial component inclination of the fixed model and varus inclination of the variable model (Fig.2). The stress on the medial tibial metaphyseal cortices did not markedly change in any inclination of fixed models, but increased in variable models as the tibial component inclination changed from varus to valgus (Fig.3A). The stress on the medial cortical rim of the resected surface increased with varus inclination in the fixed model and decreased with varus inclination in the variable model (Fig.3B). Changes in the Von Mises stress on the anterior and posterior corner of the resected surfaces did not differ between the fixed and variable model. Discussion. Varus inclination of the tibial component has been considered to increase the bone stress in previous studies. However, in the current study, bone stress on the medial metaphyseal cortex and the medial cortical rim of the resected surface conversely decreased in varus inclination when the change of the femorotibial contact point was taken into consideration. Recent opinion has advocated that restoring the constitutive patient's anatomy by compensating cartilage wear is critical in producing the excellent clinical outcome after UKA. Therefore, three to five degrees of anatomical varus inclination of the tibial component would reduce the tibial condylar bone stress and protective against complications such as unknown postoperative pain or tibial component migration. For figures/tables, please contact authors directly.

Māori consistently have poorer health outcomes compared to non-Māori within Aotearoa. Numerous worldwide studies demonstrate that ethnic minorities receive less analgesia for acute pain management. We aimed to compare analgesic management of a common orthopaedic injury, tibial shaft fracture, between Māori and non-Māori. A retrospective cohort study from January 1. st. , 2015, to December 31. st. 2020 inclusive. Eligible patients were 16–65 years old and had isolated closed tibial shaft fractures. 104 patients were included in the study, 48 Māori and 56 Non-Māori. Baseline demographics were similar between the 2 cohorts. The primary outcome measure was type of analgesia charted on the ward. Secondary outcome measures were pre-hospital medications given, pain scores on arrival to the emergency department (ED) and the ward, time to analgesia in ED and type of analgesia given in ED. Statistics were calculated using Fisher's exact test, Pearson's chi-squared test or Wilcoxson's rank sum test as appropriate. No statistically significant differences were found in opiates or synthetics charted to Māori vs Non-Māori (83% vs 89% and 77% vs 88% respectively), opiates given in ED, time to analgesia in ED or ED and ward arrival pain scores. Of statistical significance is that Māori were less likely to receive pre-hospital medication compared to Non-Māori (54% vs 80% respectively, p=0.004). Māori were significantly less likely to receive pre-hospital pain medication compared to Non-Māori. However no other statistically significant findings were found when comparing pain scores, time to analgesia or type of pain relief charted for Māori vs non-Māori. The reasons for Māori receiving significantly less prehospital medication were not explored in this study and further investigation is required to reduce the bias that exists in this area

Malalignment is a common complication following tibial surgery, occurring in 10% of fractures. This is associated with prolonged healing time and non-union. It occurs due to inability to maintain a satisfactory reduction. A reduction device, such as the Staffordshire Orthopaedic Reduction Machine (STORM), permits the surgeon to manipulate the fracture and hold it reduced. A retrospective parallel case series was undertaken of all patients undergoing tibial nails over a six-year period from 2014 to 2021. Patient demographics were obtained from medical records. Operative times obtained from the theatre IT system and included the time patient entered theatre and surgical start and finish times for each case. Anteroposterior and lateral long leg post-operative radiographs were reviewed. Angulation was measured in both coronal and sagittal planes, by two separate orthopaedic surgeons. A reduction was classified to be ‘mal-aligned’ if the angle measured was greater than 5 degrees. One tailed unpaired t-test was used to compare alignment in each plane. Bony union was assessed on subsequent radiographs and was determined according to the Radiographic Union Score for Tibial Fractures. 31 patients underwent tibial nail during the time period. 8 patients were lost to follow up and were excluded. Of the remaining 23 patients, the STORM device was utilised in 11. The overall mean alignment was acceptable across all groups at 2.17° in the coronal plane and 2.56° in the saggital plane. Analysing each group individually demonstrated an improved alignment when STORM was utilised: 1.7° (1°–3°) vs 2.54° (0°–5°) for the coronal plane and 1.6° (0°–3°) vs 3.31° (0°–9°) in the saggital plane. This difference was significant in saggital alignment (p=0.03) and showed a positive trend in coronal alignment, although was not significant (p=0.08). The time in theatre was shorter in the control group with a mean of 113 minutes (65 to 219) in comparison to STORM with a mean of 140 minutes (105 to 180), an increased theatre time of 27 minutes (p=0.04). This study demonstrates that STORM can be used in the surgical treatment of tibial fractures resulting in improved fracture alignment with a modest increase in theatre time

Introduction:. Adequate coverage of the resected tibial plateau with the tibial tray is necessary to reduce the theoretical risk of tibial subsidence after primary total knee arthroplasty (TKA). Maximizing tibial coverage is balanced against avoiding excessive overhang of the tray causing soft tissue irritation, and establishing proper tray alignment improving implant longevity and patella function. 1. Implant design factors, including the number of tray sizes, tray shape, and tray asymmetry influence the ability to cover the tibial plateau. 2. Furthermore, rotating platform (RP) tray designs decouple restoring proper tibial rotation from maximizing tibial coverage, which may enhance the ability to maximize coverage. The purpose of the current study was to assess the ability of five modern tray designs (Fig. 1), including symmetric, asymmetric, fixed-bearing, and RP designs, to maximize coverage of the tibial plateau across a large patient population. Methods:. Lower limb computed-tomography scans were collected from 14,791 TKA patients and the tibia was segmented. Virtual surgery was performed with an 8-mm tibial resection (referencing the high side) made perpendicular to the tibial mechanical axis in the frontal plane, with 3° posterior slope, and aligned transversely to the medial third of the tibial tubercle. An automated algorithm placed the largest possible tray on the plateau, optimizing the ML and AP placement (and I-E rotation for the RP tray), to minimize overhang. The largest sized tray that fit the plateau with less than 2-mm of tray overhang was identified for each of the five implant systems. The surface area of the tibial tray was divided by the area of the resected plateau and the percentage of patients with greater than 85% plateau coverage was calculated. Results:. The percentage of patients with greater than 85% plateau coverage across the tray designs ranged from 17.0% to 61.4% (Fig. 1). The tray with the greatest number of size options (Tray 4, 10 sizes) had the best coverage among the fixed-bearing trays. The RP variant of the same tray had the best overall coverage. Tibial asymmetry did not significantly improve the overall tibial coverage across the patient distribution for both asymmetric designs. Incorporating a broader medial condyle improved fit along the posterior medial corner for Tray 2, but increased the average under-hang along the posterior lateral plateau offsetting any improvement in total coverage. Discussion:. This analysis represents the most comprehensive assessment of tray coverage to date across a large TKA-patient population. Large variations exist in the size and shape of the proximal tibia among TKA patients. 3. Developing a tray design which provides robust coverage despite this variation remains challenging. This analysis suggests that tibial asymmetry may not robustly improve coverage. Conversely, incorporating an increased number of tray sizes and utilizing an RP implant to decouple coverage from alignment may provide the most reliable solution for maximizing coverage across the patient population