Introduction. Osteochondral lesions of the talus are common injuries following acute and chronic ankle sprains and fractures, the treatment strategies of which include both reparative and restorative techniques. Recently, restorative techniques (i.e., autologous osteochondral transplantation) have been become increasingly popular as a primary treatment strategy, in part due to the potential advantages of replacing “like with like” in terms of hyaline cartilage at the site of cartilage repair. The current study examines the functional results of autologous osteochondral transplantation of the talus in 72 patients. Methods. Between 2005 and 2009, 72 patients underwent autologous osteochondral transplantation under the care of the care of the senior author. The mean patient age at the time of surgery was 34.19 years (range, 16–85 years). The mean follow-up time was 28.02 months (range, 12–64 months). Patient-reported outcome measures were taken pre-operatively and at final-follow-up using the Foot and Ankle Outcome Score and Short-Form 12 general health questionnaire. Quantitative T2-mapping MRI was also performed on select patients at 1-year post-operatively. Results. The mean FAOS scores improved from 52.67 points pre-operatively to 86.19 points post-operatively (range, 71–100 points). The mean SF-12 scores also improved from 59.40 points pre-operatively to 88.63 points post-operatively (range, 52–98 points). Three patients reported donor site knee pain after surgery. Quantitative T2-mapping MRI demonstrated relaxation times that were not significantly different to those of native cartilage in both the superficial and deep halves of the repair tissue. Discussion and Conclusion. Autologous osteochondral transplantation is a reproducible and primary treatment strategy for large osteochondral lesions of the talus and provides repair tissue that is biochemically similar to that of native cartilage on quantitative T2-mapping MRI. This may ultimately allow the ankle joint to function adequately over time

Osteochondral lesions (OCL) of the talus occur in 38% of the patients with supination external rotation type IV ankle fractures and 6 % of ankle sprains. Osteoarthritis is reported subsequently in 8–48% of the ankles. Several marrow stimulation methods have been used to treat the symptomatic lesion, including arthroscopic debridement and micro fracture. Encouraging midterm results have been reported, but longterm outcome is unknown in relation to more invasive treatments such as transfer of autologous osteoarticular tissue from the knee or talus (OATS), autologous chondrocyte implantation (ACI), frozen and fresh allograft transplantation. Aim. The aim of our study was to review our long term results of arthroscopic treatment of osteochondral lesions of the talus. Materials and methods. 65 patients underwent arthroscopic treatment of the OCL between 1993 and 2000. There were 46(71%) men and 19(29%) women. The mean age at surgery was 34.2 years. The right side was affected in 43 patients and the left side in 22 patients. Results. 40/65(61.5%) patients who underwent arthroscopic treatment of the OCL were followed up. The mean follow-up was 13.1 years (9 to 18 years). The average age at final follow was 49.6 years (25–80 years). 15 (39.5%) patients reported poor, 14 (36.8%) fair, 9 (23.6%) good outcomes based on the Berndt and Harty criteria. 20/40 patients (50 %) needed further surgery. This appears a significant deterioration since this cohort were studied at 3.5 years, when the clinical results were 21.3% poor, 26.2% fair and 52.3% good, although losses to followup make exact comparison impossible. Conclusion. Arthroscopic treatment of osteochondral lesions of the talus gives medium term improvement in the majority of patients, but it appears that results deteriorate with time. Recurrence of symptoms sufficient to require further surgical intervention occurred in half the patients studied

Tibial pilon fractures are typically the result of high-energy axial loads, with complex intra- articular fractures that are often difficult to reconstruct anatomically. Only nine simultaneous pilon and talus fractures have been published previously, but we hypothesised the chondral surface of the dome is affected more frequently. Data was acquired prospectively from 154 acute distal tibial pilon fractures (AO/OTA 43B/C) in adults. Radiographs, photographs, and intra-operative drawings of each case were utilised to document the presence of any macroscopic injuries of the talus. Detailed 1x1mm maps were created of the injuries in each case and transposed onto a statistical shape model of a talus; this enables the cumulative data to be analysed in Excel. Data was analysed using a Chi-squared test. From 154 cases, 104 were considered at risk and their talar domes were inspected; of these, macroscopic injuries were identified in 55 (52.4%). The prevalence of talar dome injury was greater with B-type fractures (53.5%) than C-type fractures (31.5%) (ρ = .01). Injuries were more common in men than women and presented with different distribution of injuries (ρ = .032). A significant difference in the distribution of injuries was also identified when comparing falls and motor vehicle accidents (ρ = .007). Concomitant injuries to the articular surface of the dome of the talus are relatively common, and this perhaps explains the discordance between the post-operative appearance following internal fixation and the clinical outcomes observed. These injuries were focused on the lateral third of the dome in men and MVAs, whereas women and fall mechanism were more evenly distributed. Surgeons who operatively manage high-energy pilon fractures should consider routine inspection of the talar dome to assess the possibility of associated macroscopic osteochondral injuries

Introduction. A subset of patients in cast awaiting fixation of ankle fractures require conversion to delayed external fixation (dEF). We aimed to evaluate the effect of delayed versus planned external fixation (pEF), then identify objective characteristics contributing to need for conversion. Method. We extracted data from our booking system to identify all ankle external fixation procedures between 2010 to 2022. Exclusions included open fractures, the skeletally immature, and pilon or talus fractures. Fractures were classified using the AO/OTA classification, then a matched cohort was identified based on fracture classification. We compared the planned, delayed and matched cohorts for demographics, posterior malleolar fragment (PMF) ratio, and degree of displacement at presentation. Results. We identified 25 pEF, 42 dEF, and 67 matched patients. Ankles with dEF had a 3.8 day longer time to ORIF from presentation than those who had pEF, and had an infection rate of 9.5%, compared to 4% in the pEF group. Two patients in the dEF group required further operative intervention. There were no infections or reoperations required in the pEF or matched groups. The dEF group were more likely to have ≥2 reductions (OR 4.13), a PMF ratio of >0.23 (OR 5.07), and have increased displacement at time of injury on lateral (32% vs 19%) and AP (62% vs 36%) radiographs. Discussion. Our retrospective study highlights the longer time to operation and increased infection rates of patients who do not get timely external fixation. We propose a series of objective parameters that predict failure of cast treatment and guide the surgeon to consider planned external fixation in some ankle

Introduction. Fibula contributes to weight bearing and serves as a lateral buttress to the talus. Fibular shortening leads to ankle valgus, distal tibial epiphyseal wedging and ankle instability. Trauma, infection and skeletal dyplasias are the common causes of fibular shortening in children. Aim was to review this cohort who underwent fibular lengthening and ankle reconstruction. Materials and Methods. Retrospective review from a prospective database of clinical and radiographic data of all children who underwent fibular lengthening for correction of ankle valgus. Distraction osteogenesis with external fixator was performed for all cases. Results. Eight children with 10 fibulae (average age: 10 years) were followed up for an average of 75.6 months. In older children, corrective tibial osteotomy was performed in addition to fibular lengthening. TSF frame mounted with mini-rail fixator was used in seven children who required adjuvant tibial correction and mini-rail was used for bilateral fibular lengthening in one. Remodelling of the wedged distal tibial epiphysis was noted in 75%. Talar tilt and mLDTA improved in 66.7% and fibular station in 85.7% limbs. Seven year old girl required re-lengthening. Two children developed fibular non-union. Proximal fibular migration was observed in one child, in whom the tibial wire did not engage the fibula. Conclusions. Restoration of tibial mechanical axis and lateral talar buttress is necessary to correct ankle valgus. Stabilisation of fibula to the tibia is prudent during distraction. Younger children may require re-lengthening. Remodelling of the triangular tibial epiphysis can be achieved when done early

Purpose. The goal of Total Ankle Arthroplasty (TAA) is to relieve pain and restore healthy function of the intact ankle. Restoring intact ankle kinematics is an important step in restoring normal function to the joint. Previous robotic laxity testing and functional activity simulation showed the intact and implanted motion of the tibia relative to the calcaneus is similar. However there is limited data on the tibiotalar joint in either the intact or implanted state. This current study compares modern anatomically designed TAA to intact tibiotalar motion. Method. A robotic testing system including a 6 DOF load cell (AMTI, Waltham, MA) was used to evaluate a simulated functional activity before and after implantation of a modern anatomically designed TAA (Figure 1). An experienced foot and ankle surgeon performed TAA on five fresh-frozen cadaveric specimens. The specimen tibia and fibula were potted and affixed to the robot arm (KUKA Robotics Inc., Augsburg, Germany) while the calcaneus was secured to a fixed pedestal (Figure 1). Passive reflective motion capture arrays were fixed to the tibia and talus and a portable coordinate measuring machine (Hexagon Metrology Group, Stockholm, Sweden) established the location of the markers relative to anatomical landmarks palpated on the tibia. A four camera motion capture system (The Motion Monitor, Innovative Sports Training, Chicago, IL) recorded the movement of the tibia and talus. The tibia was rotated from 30 degrees plantar flexion to 15 degrees dorsiflexion to simulate motions during the stance phase of gait. At each flexion angle the robot found the orientation which zeroed all forces and torques except compressive force, which was either 44N or 200N. Results. Preliminary data indicates the tibiotalar motion of the TAA is similar to the intact ankle. The pattern and magnitude of tibiotalar translations and rotations are similar between the intact and implanted states for both 44N and 200N compressive loads (Figure 2). The most variation occurs with internal-external rotation. Increased translation especially in the anterior-posterior directions was observed in plantarflexion while the mediolateral translation remained relatively centered moving less than a millimeter. The intact talus with respect to the calcaneus had less than 3 degrees of rotation over the whole arc of ankle flexion (Figure 3). The angular motion of the implanted talus was similar in pattern to the intact talus, however there were offsets in all three angular directions which changed depending on the loading (Figure 3). This indicates that most of the motion that occurs between the intact tibial calcaneal complex occurs in the tibiotalar joint. Conclusion. Although more investigation is required, this study adds to the limited available tibiotalar kinematic data. This current study suggests the anatomical TAA design allows the tibiotalar joint to behave in similar way to the intact tibiotalar joint. Restoring intact kinematics is an important step in restoring normal function to the joint. For figures/tables, please contact authors directly.

Introduction. Osteochondral autologous autograft (also called mosaic arthroplasty) is the preferred treatment method for very large osteochondral defects in the ankle. For long-term success of this procedure, the transplanted plugs should reconstruct the curvature of the articular surface. The different curvatures between femoral-patella joint and the dome of the talus makes the reconstruction difficult and requires lots of experience. Material. Prior to the surgery a CT arthrogram of the ankle, as well as a CT of the knee were obtained and 3D bone models for the knee, the ankle as well as a model for the ankle cartilage were created. Using custom-made software a set of osteochondral grafts (“plugs”) positioned over the defect site were planned and an optimal harvest location for each plug was chosen. Intraoperatively, an optoelectronic navigation system was installed and sensors were attached to femur, talus, and conventional harvest and delivery chisels. A combined pair-point and surface matching was performed to register femur and talus. For each planned plug the surgeon positioned, oriented, and rotated the harvest and delivery chisels with respect to preoperative plan by using the visual and numerical feedback of the system. Results. We performed the above described procedure on a 37 year old female patient with osteochondral injury of the dome of the right talus with an approximate size of 20mm × 9mm. One 8mm and two 6mm plugs were planned and intraoperative navigated. At 6 months postoperative she had a significant improvement in her passive range of motion from 0–15° dorsi-flexion and 0–60° plantar-flexion, compared to her uninjured ankle of 0–15° dorsi-flexion and 0–80° plantar-flexion. The inversion and eversion of the ankle are normal and x-ray evaluation showed good and complete integration of the osteochrondal plugs. Discussion. A virtual preoperative planning tool helped to solve the complex geometrical problem of reconstructing the articular cartilage surface of the talus using multiple autologous osteochondral plugs from the knee. The intraoperative optoelectronic guidance allowed the surgeon to transfer this plan into the intraoperative situation

Tunning fork lines (TFL) were drawn on ankle anterior-posterior radiographs to assess the talar shift in ankle fractures. A 3-D ankle joint reconstruction was prepared by mapping normal ankle joint using auto CAD in 1997. TFL were drawn using normal anatomical landmarks on saggital, coronal and transverse planes. The ankle joint anatomical relationship with talus was studied in various rotation simulating radiographic anterior-posterior views and talar shift was studied. Between 2006 and 2012 on antero-posterior view of ankle radiographs and PACS, TFL were drawn. The premise is that in a normal radiograph the superior-lateral dome of the talus lies medial to the handle of TFL, and in ankle with talar shift the dome of the talus would cross this line laterally. In two district hospitals 100 radiographs were observed by 4 observers in 67 males and 33 females with mean age of 49 (15–82) years. The TFL confirmed talar shift with sensitivity of 99.2 % showing talarshift and inferior tibio-fibular ankle diastasis. We conclude that in ankle anterio-posterior view it is possible to comment on the talar shift and diastasis of the ankle joint, even if proper ankle mortise views were not available

Purpose. One of the current research topics is the aim to produce tissue engineered osteochondral grafts for future treatment of osteochondral lesions (OCL) of the talus. For the exact anatomic reconstruction, the dimensions of the medial and lateral talar dome must be considered. Sparse data is available regarding the normal anatomic talar dimensions on standard radiographs of ankle joints [1, 2]. The purpose of this study was to describe normal anatomy of different sections of the talar dome on 3D reconstructions of computertomographic (CT) images. Method. CT data sets (Somatom 10, Siemens Erlangen, Germany) of 82 patients (86 ankles) (28 female, 54 male; average age 41.9y (range 15–76y)) without talar pathologies were included. Measurements were performed with a geometry analysis software (VGStudio MAX 2.0, Volume Graphics, Heidelberg, Germany). To assure measurement reproducibility, the reference planes were defined in a first step. To measure the frontal talar edge radius, circles were fitted into the medial and lateral talar edge on frontal planes. To allow measurement of different segments of the talus, the frontal plane was tilted through the center of the talus (defined as a circle fitted to the talus on sagittal view) at 15 and 30 anteriorly and posteriorly. To measure the sagittal radius of the medial and talar edge, ircles were fitted into the medial and lateral talar edge on sagittal planes. Results. The talar edge radius in the frontal plane at 0 wa s 4.9 mm medially (3.0 mm laterally), at 15 ant. 4.2 mm (3.1 mm), at 30 ant. 4.6 mm (3.1 mm), at 15 post. 4.5 mm (3.9 mm), and at 30 post 4.1 mm (6 mm). There was a significant difference (p<0.01) between the mean medial and lateral talar edge radius at all angles. The talar edge radius in the sagittal plane was 20.4 mm medially and 20.3 laterally. There was no significant difference between the mean medial and lateral sagittal talar edge radius. Conclusion. This study shows a significant difference between physiological medial and lateral edge configuration at different frontal planes of the talar dome. No difference was found comparing the sagittal radius of the medial and talar dome. The assessed data provides important aid for engineering of pre-formed, pre-sized osteochondral grafts. Such pre-shaped grafts could help restoring the physiological joint surface by matching exactly into the lesion and consequently achieving the recovery of the physiological joint biomechanics and prevention of secondary degenerative disease

Optimal treatment for symptomatic talus Osteochondral Lesions (OCLs) where primary surgical techniques have failed has not been established. Recent advances have focussed on biological repair such as Autologous Chondrocyte Implantation (ACI) however funding for this treatment is limited. Stem cell therapy in the ankle has not been assessed. The purpose of this pilot study was to evaluate the safety and efficacy of stem cell therapy in the treatment of ankle OCLs. The study was approved by the new procedures committee. Between January 2015 and December 2016, 26 patients, mean age of 36 years (range 16–58 years) with persisting disabling symptoms underwent Complete Cartilage Regeneration (CCR) using stem cells for failed primary treatment for ankle OCLs. Treatment involved iliac crest bone marrow aspiration, centrifugation to obtain bone marrow concentrate (BMC), and then injection of the BMC combined with hyaluronic acid into the OCL. Any necessary additional procedures, e.g. bone grafting or lateral ligament reconstruction were also undertaken. In 18 patients the lesion was on the medial talar dome, in 5 the lateral talar dome, 2 multiple, 1 tibial plafond. The Manchester-Oxford Foot Questionnaire (MOXFQ) was utilised to assess outcome. Average pre-operative MOXFQ scores were Walking dimension −78, Pain dimension − 65, and Social dimension − 64.2. Average 3 month post-operative MOXFQ scores were Walking − 54.8, Pain − 35.4, Social − 38.9. Average 6 month post-operative MOXFQ scores were Walking − 34.4, Pain − 35.4, Social − 28. Two patients from the beginning of the series had AOFAS scores only which improved from an average of 55 pre-operatively to 76 post-operatively. No early complications were noted. We conclude that CCR treatment is a safe treatment for talus OCLs in patients who have failed primary treatment. The procedure avoids two-stage surgery of ACI in some patients without large cysts. The early clinical outcome is favourable with no complications noted. Longer term follow-up is required

This study aimed to evaluate the clinical outcomes of paediatric patients who underwent a retrograde drilling treatment for their osteochondritis dissecans (OCD) of the talus. The secondary purpose was to identify factors that are predictive of a failure of the treatment. A retrospective study was done. All patients treated for talar OCD between 2014 and 2017 were reviewed to extract clinical and demographic information (age, sex, BMI, OCD size and stability, number of drilling, etc). Inclusion criteria were: (1) talar OCD treated with retrograde drilling, (2) less than 18 years, (3) at least one available follow up (4) stable lesion. Exclusion criteria was another type of treatment for a the talar OCD. Additionally, all pre-operative and post-operative medical imaging was reviewed. Outcome was classified based on the last follow-up appointment in two ways, first a score was attributed following the Berndt and Harty treatment outcome grading and second according to the necessity of a second surgery which was the failure group. Chi-square and Mann-Whitney tests were used to compared the success and failure group. Seventeen patients (16 girls and 1 boy, average age: 14.8±2.1 years) were included in our study group. The mean follow up duration was 11.5 (±12) months. Among this population, 4/17 (24%) had a failure of the treatment because they required a second surgery. The treatment result grading according to Berndt and Harty outcome scale identified good results in 8/17 (47%) patients, fair results in 4/17(24%) patients and poor results in 5/17 (29%) patients. The comparisons for various patient variables taken from the medical charts between patients who had a success of the treatment and those who failed did not find any significant differences. At a mean follow-up duration of 11.5 months, 76% of patients in this study had a successful outcome after talar OCD retrograde drilling. No statistically significant difference was identified between the success and failure group. Talar OCD in a paediatric population is uncommon, and this study reviewed the outcome of retrograde drilling with the largest sample size of the literature. Retrograde drilling achieved a successful outcome in 76% of the cases and represents a good option for the treatment of stable talar OCD

The purpose of this study was to obtain anatomical measurements of the distal tibia and talus of Korean ankles and to evaluate, based on those measurements, the compatibility of the HINTEGRA prostheses in the context of total ankle replacement (TAR). We measured the length, width, height, and angles of the distal tibia and talus of 51 cadavers and compared these measurements with the corresponding dimensions of the HINTEGRA prostheses. The male ankles were larger than the female ones as was expected, but their overall shapes did not differ, which fact validates use of the prostheses irrespective of patients' sex. The dimensions of the talus itself did not differ significantly from those previously reported for American whites and blacks and South African whites. This might suggest a possibility that the HINTEGRA prostheses, being used in these countries, would be compatible to Korean ankles, too. In fact, the length range of the talar components was generally compatible with those derived from cadaveric measurements of the trochlea. However, the widths of the tibial and talar components were not completely compatible to Korean ankles. Above all, the length of the large-sized tibial components was much longer than the largest ankles, which would confine the choice of prosthesis mainly to small-sized ones for arthroplasty in Korea. Even though these prostheses are currently used, some modifications are needed to extend their usability in Korea, such as shortening and width/length ratio adjustment of the tibial component, and of the talar component accordingly

Tunning fork lines (TFL) were drawn on ankle anterior-posterior radiograph to assess the talar shift. A 3-D ankle joint reconstruction was prepared by mapping normal ankle joint using auto CAD in 1997. Tunning fork lines were drawn using normal anatomical landmarks on saggital, coronal and transverse planes. The ankle joint anatomical relationship with talus was studied in various rotation simulating radiographic anterior-posterior views and talar shift was studied. Between 2006 and 2012 on antero-posterior view of ankle radiographs and PACS, ‘Tunning Fork Lines’ (TFL) were drawn. The superior two vertical lines of the TFL were drawn above the ankle joint perpendicular to the distal tibial articular surface. First line tangent to anterior lip of the inferior tibio-fibular joint and second line tangent to the posterior lip of the inferior tibio-fibular joint parallel to each other. The horizontal third line was drawn parallel to distal tibial articular surface perpendicular to first two lines connecting them. The fourth line (handle of the tunning fork) was drawn vertically below the ankle joint midway between the first two lines perpendicular to the third line. In a normal radiograph the superior-lateral dome of the talus lies medial to the handle of TFL, and in ankle with talar shift the dome of the talus crosses this line laterally. In two district hospitals 100 radiographs were observed by 4 observers in 67 males and 33 females with mean age of 49 (15–82) years. The TFL confirmed talar shift with sensitivity of 99.2 % showing talarshift and inferior tibio-fibular ankle diastasis. We conclude that in ankle anterio-posterior view it is possible to comment on the talar shift and diastasis of the ankle joint if proper ankle mortise view is not available

Purpose. Osteochondral lesions (OCL) of the talus remain a challenging therapeutic task to orthopaedic surgeons. Several operative techniques are available for treatment, e.g. autologous chondrocyte implantation (ACI), osteochondral autograft transfer system (OATS), matrix-induced autologous chondrocyte implantation (MACI). Good early results are reported; however, disadvantages are sacrifice of healthy cartilage of another joint or necessity of a two-stage procedure. This case describes a novel, one-step operative treatment of OCL of the talus utilizing the autologous matrix-induced chondrogenesis (AMIC) technique in combination with a collagen I/III membrane. Method. 20 patients (8 female, 12 male; mean age 36, range 17–55 years) were assessed in our outpatient clinic for unilateral OCL of the talus. Preoperative assessment included the AOFAS hindfoot scale, conventional radiography, magnetresonancetomography (MRI) and SPECT-CT. Surgical procedure consisted of debridement of the OCL, spongiosa plasty from the iliac crest and coverage with the I/III collagen membrane (Chondrogide, Geistlich Biomaterials, Wolhusen, Switzerland). Clinical and radiological followup was performed after one year. Results. The mean preoperative AOFAS hindfoot scale was poor with 63.1 points (SD 19.6). At one year followup the score improved significantly (p<0.01) to 86 points (SD 12). At one year followup conventional radiographs showed osseous integration of the graft in all cases. MRI at one year showed intact cartilage covering the lesions in all cases. Conclusion. The initial results of this ongoing study are encouraging. The clinical and radiological results at one year followup are comparable with the results of ACI, OATS and MACI. The AMIC procedure is a readily available, economically efficient, one step surgical procedure. No culturing after chondrocyte harvesting or destruction of viable cartilage is necessary

Aims

Excision of chronic osteomyelitic bone creates a dead space which must be managed to avoid early recurrence of infection. Systemic antibiotics cannot penetrate this space in high concentrations, so local treatment has become an attractive adjunct to surgery. The aim of this study was to present the mid- to long-term results of local treatment with gentamicin in a bioabsorbable ceramic carrier.

INTRODUCTION. Proper ligament engagement is an important topic of discussion for total knee arthroplasty; however, its importance to total ankle arthroplasty (TAA) is uncertain. Ligaments are often lengthened or repaired in order to achieve balance in TAA without an understanding of changes in clinical outcomes. Unconstrained designs increase ankle laxity,. 1. but little is known about ligament changes with constrained designs or throughout functional activity. To better understand the importance of ligament engagement, we first investigated the changes in distance between ligament insertions throughout stance with different TAA designs. We hypothesize that the distance between ligaments spanning the ankle joint would increase in specimens following TAA throughout stance. METHODS. A validated method of measuring individual bone kinematics was performed on pilot specimens pre- and post-TAA using a six-degree-of-freedom robotic simulator with extrinsic muscle actuators and motion capture cameras (Figure 1). 2. Reflective markers attached to surgical pins and radiopaque beads were rigidly fixed to the tibia, fibula, talus, calcaneus, and navicular for each specimen. TAAs were performed by a fellowship-trained foot and ankle surgeon on two specimens with separate designs implanted (Cadence & Salto Talaris; Integra LifeSciences; Plainsboro, NJ). Each specimen was CT-scanned after robotic simulations of stance pre- and post-TAA. Specimens were then dissected before a 3D-coordinate measuring device was used to digitize the ligament insertions and beads. Ligament insertions were registered onto the bone geometries within CT images using the digitized beads. Individual bone kinematics measured from motion capture were then used to record the point-to-point distance between centers of the ligament insertions throughout stance. RESULTS. Results from the pilot specimens are presented for the calcaneofibular ligament (CFL) only. The distance between the CFL insertions was larger throughout stance following Cadence implantation (Figure 2A) and was decreased throughout most of stance following Salto Talaris implantation (Figure 2B). The percent change in CFL distance with respect to static standing was also increased with the Cadence implant (Figure 2C) and similar to intact following Salto Talaris implantation (Figure 2D). Ankle motion was similar to intact with the Cadence (Figure 3A) and was decreased with the Salto Talaris (Figure 3B). DISCUSSION. This study suggests that ligament length during stance changes following TAA. The Cadence implant similarly replicated ankle kinematics but CFL length was increased throughout stance which supports our hypothesis. In contrast, the Salto Talaris implant reduced ankle motion and decreased the CFL length. Although the slack length and pre-strain of the CFL were unknown, the distance between insertions from the pilot specimens provides preliminary insight into how ligament mechanics change post-TAA during functional activity. CLINICAL RELEVANCE. Preliminary results of ligament length changes throughout stance may indicate that ligament mechanics change post-TAA and could affect patient outcomes. Changes may be even more pronounced when a soft tissue release or reconstruction is performed to correct malalignment. For any figures or tables, please contact the authors directly

Total ankle arthroplasty is used as a treatment for end stage arthritis of the ankle. Surgical techniques highlight risk of injury to anterior neurovascular structures. No literature highlights injury risk to the posterior neurovascular structures in ankle replacement surgery. Current literature consists of cadaveric study in relation posterior ankle arthroscopy. A retrospective review was done of ankle MRI's, performed by the senior author in his practice. Studies were included in the study where there was no pathology of the posterior ankle present. Axial, coronal and sagital T1 weighted films were reviewed and measurements of the posterior neurovascular structures and tendons were made in relation to the posterior tibia and medial malleolus in relation to planned tibial and talar cutting planes. A total of seventy-eight MRI's were included in the study (ages ranged from 22 to 78 years). There were 40 females and 38 males. At the level of the tibial cut the tibial nerve and artery were between two to six millimeters from the posterior surface of the tibia. The flexor hallucis longus (FHL) is located in the midline between the medial malleolus and fibula, closely related to the posterior tibial surface. The flexor digitorum longus (FDL) tendon is located in the posterior medial corner of the ankle. There is a window approx ten millimeters wide between where the neurovascular structures lie between the FDL and FHL tendons. At the level of the talus cut the tibial nerve and artery were between five to 11 mm from the posterior body of the talus. A similar window is present at this level where the neurovascular structures lie between the FDL and FHL tendons. The neurovascular structures of the ankle are potentially at risk during the tibial and talar bone resection. They are most at risk with the transverse cut of the tibia. This may be decreased by preventing direct pressure over these structures during bone resection

Background. Total ankle arthroplasty is an accepted alternative to arthrodesis of the ankle. However, complication and failure rates remain high compared to knee and hip arthroplasty. Long-term results of the Scandinavian Total Ankle Replacement (STAR) are limited, with variable complication and failure rates observed. This prospective study presents the long-term survivorship and the postoperative complications of the STAR prosthesis. Additionally, clinical outcomes and radiographic appearance were evaluated. Methods. Between May 1999 and June 2008, 134 primary total ankle arthroplasties were performed using the STAR prosthesis in 124 patients. The survivorship, postoperative complications and reoperations were recorded, with a minimum follow-up period of 7.5 years. Clinical results were assessed using the Foot Function Index (FFI) and the Kofoed score. The presence of component migration, cysts and radiolucency surrounding the prosthesis components, heterotopic ossifications and progression of osteoarthritis in adjacent joints were determined. Results. The cumulative survival was 78% after a 10-year follow-up period (Figure 1). An ankle arthrodesis was performed in the 20 ankles that failed. Fourteen polyethylene insert fractures occurred. Other complications occurred in 29 ankles, requiring secondary procedures in 21 ankles. Nevertheless, the postoperative clinical results improved significantly. Osteolytic cysts were observed in 59 ankles and the surface area of these cysts increased during follow-up, without any association with the prosthesis alignment or clinical outcome. Heterotopic ossifications at the medial malleolus were present in 58 cases and at the posterior tibia in 73 cases, with no effect on clinical outcome. Osteoarthritis of the subtalar joint and talonavicular joint developed in 9 and 11 cases, respectively. Conclusion. The long-term clinical outcomes for the STAR were found to be satisfactory. These results are consistent with previous studies; however, the survival and complication rates are still disappointing compared to the results obtained in knee and hip arthroplasty. Higher rates of successful outcomes following ankle arthroplasty are required, and these results highlight the need for further research to clarify the origin and significance of the reported complications. Figure 1. Kaplan-Meier survivorship analysis with revision or removal of the tibia and/or the talus component for any reason as the endpoint, showing 78% (95% confidence interval 0.63–0.88) survival at 10.28 years follow-up. For figure, please contact authors directly

Restoration of natural range and pattern of motion is the primary goal of joint replacement. In total ankle replacement, proper implant positioning is a major requirement to achieve good clinical results and to prevent instability, aseptic loosening, meniscal bearing premature wear and dislocation at the replaced ankle. The current operative techniques support limitedly the surgeon in achieving a best possible prosthetic component alignment and in assessing proper restoration of ligament natural tensioning, which could be well aided by computer-assisted surgical systems. Therefore the outcome of this replacement is, at present, mainly associated to surgeon's experience and visual inspection. In some of the current ankle prosthetic designs, tibial component positioning along the anterior/posterior (A/P) and medio/lateral axes is critical, particularly in those designs not with a flat articulation between the tibial and the meniscal or talar components. The general aim of this study was assessing in-vitro the effects of the A/P malpositioning of the tibial component on three-dimensional kinematics of the replaced joint and on tensioning of the calcaneofibular (CaFiL) and tibiocalcaneal (TiCaL) ligaments, during passive flexion. Particularly, the specific objective is to compare the intact ankle kinematics with that measured after prosthesis component implantation over a series of different positions of the tibial component. Four fresh-frozen specimens from amputation were analysed before and after implantation of an original convex-tibia fully-congruent three-component design of ankle replacement (Box Ankle, Finsbury Orthopaedics, UK). Each specimen included the intact tibia, fibula and ankle joint complex, completed with entire joint capsule, ligaments, muscular structures and skin. The subtalar joint was fixed with a pin protruding from the calcaneus for isolating tibiotalar joint motion. A rig was used to move the ankle joint complex along its full range of flexion while applying minimum load, i.e. passive motion. In these conditions, motion at the ankle was constrained only by the articular surfaces and the ligaments. A stereofotogrammetric system for surgical navigation (Stryker-Leibinger, Freiburg, Germany) was used to track the movement of the talus/calcaneus and tibial segments, by using trackers instrumented with five active markers. Anatomical based kinematics was obtained after digitization by an instrumented pointer of a number of anatomical landmarks and by a standard joint convention. The central point of the attachment areas of CaFiL e TiCaL was also digitised. Passive motion and ankle joint neutral position were acquired, and the standard operative technique was performed to prepare the bones for prosthesis component implantation. The final component for the talus was implanted, the tibial component was initially positioned well in front of the nominal right (NR) position, the meniscal bearing was instrumented with an additional special tracker, and passive motion was collected again in passive flexion. Data collection was repeated for progressively more posterior locations for the tibial component, for a total of six different locations along the tibial A/P axis: three anterior (PA), the NR, and two more posterior (PP), approximately 3 to 5 mm far apart each. The following three-dimensional kinematics variables were analyzed: the three anatomical components of the ankle joint (talus-to-tibial) rotation (dorsi/plantar flexion, prono/supination and internal/external rotation respectively in the sagittal, frontal and transverse planes), the meniscal bearing pose with respect to the talar and tibial components, the ‘ligament effective length fraction’ as the ratio between the instantaneous distance between the ligament attachment points and the corresponding maximum distance, and the instantaneous and mean helical axes in the tibial anatomical reference frame. In all specimens and in all conditions, physiological ranges of flexion, prono/supination and internal/external rotation were observed at the ankle joint. A good restoration of motion was observed at the replaced joint, demonstrated also by the coupling between axial rotation and flexion and the physiological location of the mean helical axis, in all specimens and in most of the component positions. Larger plantar- and smaller dorsi-flexion were observed when the tibial component was positioned more anteriorly than NR, and the opposite occurred for more posterior positions. In regards to the meniscal bearing, rotations were small and followed approximately the same patterns of the ankle rotations, accounted for the full conformity of the articulating surfaces. Translations in A/P were larger than in other directions, the bearing moving backward in plantarflexion and forward in dorsiflexion with respect to both components. It was observed that the closer to NR the position of the tibial component is, the larger this A/P motion is, accounted mainly to the associated larger range of flexion. The change of CaFiL and TiCaL effective length fraction over the flexion arc was found smaller than 0.1 in three specimens, smaller than 0.2 in the fourth, larger both in more anterior and more posterior locations of the tibial component. The simulated malpositioning did not affect much position and orientation of the mean helical axis in both the transversal and frontal planes. The experimental protocol and measurements were appropriate to achieve the proposed goals. All kinematics variables support the conclusion that the ankle replaced with this original prosthesis behaves as predicted by the relevant computer models, i.e. physiological joint motion and ligament tension is experienced resulting in a considerable A/P motion of the meniscal bearing. These observations are particularly true in the NR postion for the prosthesis, but are somehow correct also in most of the tibial malpositions analysed, in particular those on the back

Aim. Open fractures with bone loss and skin lesions carry a high risk of infection and complication. Treatment options are usually a two-stage approach (debridement, temporary stabilization with external fixation followed by open reduction and stabilization with plate). We describe an experience for a single stage procedure with an antibiotic eluting bone graft substitute (BGS) for prophylaxis of implant-related infection. Method. Between December 2014 and January 2016 were analysed the data of twenty-six patients with open fractures (Gustilo and Anderson grade I and II) or with skin lesion and high risk of contamination and bone loss. They where treated with debridement of soft tissue, closed reduction of fracture, placement of a plate augmented with BGS eluting antibiotic (gentamicin (1) and/or Vancomicin (2)). Ampicillin and sulbactam 3g three times daily was used as systemic antibiotic prophylaxis minimum for one week. Clinical outcome and radiographic bone defect filling were assessed by blinded observers. Results. From 2014 to 2015 twelve male and fourteen female with mean age 53yrs (24–77) were treated with plate and BGS. Fracture locations were four distal femur (m:4; f: 1), four tibial plateau (m:3; f:1), one proximal humerus (f:1), seven calcaneus (m:4; f: 3), one talus (m:1), four forearm (m:3), one elbow (f:1) and two phalanx (m: 2). Follow up was fourteen month (range: 3 – 26 months). During follow-up no implant-related infection was observed. One patient developed sterile seroma, which was treated conservatively. The calcium sulphate phase of BS dissolved in all cases within 4–6 weeks. Bone ingrowth was assessed at 1, 2, 3, 6 and 12 months. On six patients large bone was treated with a revision surgery (autologous cancellous bone graft combined with BGS and antibiotic. No complications were reported. Conclusions. We suggest the application of poly therapy for the treatment of bone defects. BGS eluting antibiotic is easy to use and offers the opportunity for a one-stage procedure and might reduce the risk of implanted-related infection and allow early joint mobilization. Good early clinical outcomes were observed in almost all cases. More studies and larger series are necessary to confirm the potential for the prophylaxis of infection in the treatment of open fractures. (1): CERAMENT™|G. (2): CERAMENT™|V”