Abstract. Objectives. This abstract provides an update on the Open Ankle Models being developed at the University of Bath. The goal of this project is to create three fully open-source finite element (FE) ankle models, including bones, ligaments, and cartilages, appropriate musculoskeletal loading and boundary conditions, and heterogeneous material property distribution for a standardised representation of ankle biomechanics and pre-clinical ankle joint analysis. Methods. A computed tomography (CT) scan data (pixel size of 0.815 mm, and slice thickness of 1 mm) was used to develop the 3D geometry of the bones (tibia, talus, calcaneus, fibula, and navicular). Each bone was given the properties of a heterogeneous elastic material based on the CT greyscale. The density values for each bone element were calculated using a linear empirical relation, ρ= 0.0405 + (0.000918) HU and then power law equations were utilised to get the Young's Modulus value for each bone element [1]. At the bone junction, a thickness of cartilage ranging from 0.5–1 mm, and was modelled as a linear material (E=10 MPa, ν=0.4 [2]). All ligament insertions and positions were represented by four parallel spring elements, and the ligament stiffness and material attributes were applied in accordance with the published literature [2]. The ankle model was subjected to static loading (balance standing position). Four noded tetrahedral elements were used for the discretization of bones and cartilages. All degrees of freedom were restricted at the proximal ends of the tibia and fibula. The ground reaction forces were applied at the underneath of the calcaneus bone. The interaction between the cartilages and bones was modelled using an augmented contact algorithm with a sliding elastic contact between each cartilage. A tied elastic contact was used between the cartilages and the bone. FEbio 2.1.0 (University of Utah, USA) was used to construct the open-source ankle model. Results. When the double-legged stance phase loading condition was taken into consideration, stress at the antero-medial tibial wall (ranged from 1 to 7 MPa) was found to be similar to the prior work [2], indicating bulk of the load transfer was through this region. The maximum principal strain was predicted at the different regions on bones around the ankle joint. The proximal surface of the talus, and tibial distal surface were shown to have the highest maximum principal strains followed by antero-medial walls of the tibia bone, at the proximal location. Conclusions. The present open 3D FE model of the ankle will assist researchers in better understanding ankle biomechanics, precisely predicting load transfer, and examining the ankle to address unmet clinical needs for this joint. The results of the current investigation are realistic in terms of load transfer and stress-strain distribution across the ankle joint and well comparable to those reported in the literature [2]. However, sensitivity and ankle instability simulations will be performed in future work to investigate the model's reliability and robustness. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Aims . To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the pressure characteristics of the ankle joint. Materials and Methods. Varus and valgus malalignment of the knee was simulated in human cadaver full-length legs. Testing included four measurements: baseline malalignment, 5° and 10° re-aligning osteotomy, and control baseline malalignment. For HTO, testing was rerun with the subtalar joint fixed. In order to represent half body weight, a 300 N force was applied onto the femoral head. Intra-articular sensors captured ankle pressure. Results. In the absence of restriction of subtalar movement, insignificant migration of the centre of force and changes of maximal pressure were seen at the ankle joint. With restricted subtalar motion, more significant lateralisation of the centre of force were seen with the subtalar joint in varus than in valgus position. Changes in maximum pressure were again not significant. . Conclusion. The re-alignment of coronal plane knee deformities by HTO and DFO altered ankle pressure characteristics. When the subtalar joint was fixed in the varus position, migration of centre of force after HTO was more significant than when the subtalar joint was fixed in valgus. Cite this article: Bone Joint J 2017;99-B:59–65

A cavovarus foot deformity was simulated in cadaver specimens by inserting metallic wedges of 15° and 30° dorsally into the first tarsometatarsal joint. Sensors in the ankle joint recorded static tibiotalar pressure distribution at physiological load. The peak pressure increased significantly from neutral alignment to the 30° cavus deformity, and the centre of force migrated medially. The anterior migration of the centre of force was significant for both the 15° (repeated measures analysis of variance (ANOVA), p = 0.021) and the 30° (repeated measures ANOVA, p = 0.007) cavus deformity. Differences in ligament laxity did not influence the peak pressure. These findings support the hypothesis that the cavovarus foot deformity causes an increase in anteromedial ankle joint pressure leading to anteromedial arthrosis in the long term, even in the absence of lateral hindfoot instability

Aims: To identify the distraction forces and contact pressures of the ankle joint at two different joint positions during articulated ankle distraction. Material and Methods: Four amputated lower limbs were collected from patients undergoing amputation for vascular disease and frozen at -70° C. The ankle joint of the specimens were normal. Before use the limbs were thawed at room temperature for 24 hours. The skin and subcutaneous tissues were removed. A Sheffield ring fixator consisting of a proximal tibial ring and a foot plate connected through three threaded bars and hinges aligned with ankle axis was mounted on the limb. Force transducers were placed in the threaded bars between the tibial ring and the foot plate on the lateral, medial and posterior aspect of the ankle joint to measure the ankle distraction forces. Once the ankle distraction forces have been measured an anterior ankle arthrotomy was performed to permit the insertion of Fuji pressure sensitive film within the ankle joint. The limb-fixator construct was mounted in a loading machine and axially loaded on the tibia. The ankle joint was distracted at 2 mm intervals to a maximum of 20 mm. Pressure sensitive film was introduced in the ankle joint at each distraction interval and the tibia was axially loaded at 350, 700, 1050 and 1400N (half to two times body weight). Results: The forces necessary to distract the ankle joint are almost double in the medial side than the lateral side. With 10° of plantarflexion the forces necessary to distract the lateral side increase by about 10%. We found the center of pressure of the ankle joint to be situated in the antero-medial quadrant, close to the center of the ankle joint. Distraction of the ankle joint by 5 mm eliminated any contact pressures at the ankle joint when the tibia was loaded up to 700N (one time body weight). When the joint was distracted by 10 mm no contact pressures were found in the ankle when loaded up to 1400N (two times body weight). Conclusions: With the ankle in the plantigrade position the forces necessary to distract the ankle joint are double in the medial side when compared to the lateral side. Plantarflexion increases the forces necessary to distract the lateral aspect of the ankle. This finding may have clinical implications when distracting ankle joints with equinus deformities as this can increase the risk of damaging the lateral ankle ligaments leading to ankle instability. In our opinion equinus deformities should be corrected before the start of ankle joint distraction. The center of pressure of the ankle joint is situated in the antero-medial quadrant. Distraction of 5 mm will eliminate ankle contact pressure up to one times body weight whereas distraction of 10 mm will eliminate contact pressures up to two times body weight

Introduction. Deformity of knee joint causes deviation of mechanical axis in the coronal plane, and the mechanical axis deviation also could adversely affect biomechanics of the ankle joint as well as the knee joint. Particularly, most of the patients undergoing total knee arthroplasty (TKA) have significant preoperative varus malalignment which would be corrected after TKA, the patients also may have significant changes of ankle joint characteristics after the surgery. This study aimed 1) to examine the prevalence of coexisting ankle osteoarthritis (OA) in the patients undergoing TKA due to varus knee OA and to determine whether the patients with coexisting ankle OA have more varus malalignment, and 2) to evaluate the changes of radiographic parameters for ankle joint before and 4 years after TKA. Methods. We evaluated 153 knees in 86 patients with varus knee OA who underwent primary TKA. With use of standing whole-limb anteroposterior radiographs and ankle radiographs before and 4 years after TKRA, we assessed prevalence of coexisting ankle OA in the patients before TKA and analyzed the changes of four radiographic parameters before and after TKA including 1) the mechanical tibiofemoral angle (negative value = varus), 2) the ankle joint orientation relative to the ground (positive value = sloping down laterally), 3) ankle joint space, and 4) medial clear space. Results. Of the 153 knees, 59 (39%) had radiographic ankle OA. The knees with ankle OA had significantly more varus mechanical tibiofemoral angle preoperatively than those without ankle OA (− 11.9° vs. − 9.3° on average, respectively; P = 0.003). Compared to the preoperative condition, the ankle joint orientation relative to the ground significantly changed after TKA (from 9.0° to 4.8° on average, P<0.001) while ankle joint space and medial clear space did not. Conclusions. Our study revealed that coexisting ankle OA would be common in patients with varus knee OA, particularly in patients with more varus malalignment. TKA also significantly changes the ankle joint orientation relative to the ground which shows more parallel to the ground. However, its effect on ankle joint space and medial clear space seems to be minimal upto 4 years after TKA. Our findings warrant consideration in preoperative evaluations of ankle OA in varus knee OA patients undergoing TKA, and further studies should evaluate prospectively the clinical implications of radiographic change of the ankle joint after TKA

Aims. Accurate identification of the ankle joint centre is critical for estimating tibial coronal alignment in total knee arthroplasty (TKA). The purpose of the current study was to leverage artificial intelligence (AI) to determine the accuracy and effect of using different radiological anatomical landmarks to quantify mechanical alignment in relation to a traditionally defined radiological ankle centre. Methods. Patients with full-limb radiographs from the Osteoarthritis Initiative were included. A sub-cohort of 250 radiographs were annotated for landmarks relevant to knee alignment and used to train a deep learning (U-Net) workflow for angle calculation on the entire database. The radiological ankle centre was defined as the midpoint of the superior talus edge/tibial plafond. Knee alignment (hip-knee-ankle angle) was compared against 1) midpoint of the most prominent malleoli points, 2) midpoint of the soft-tissue overlying malleoli, and 3) midpoint of the soft-tissue sulcus above the malleoli. Results. A total of 932 bilateral full-limb radiographs (1,864 knees) were measured at a rate of 20.63 seconds/image. The knee alignment using the radiological ankle centre was accurate against ground truth radiologist measurements (inter-class correlation coefficient (ICC) = 0.99 (0.98 to 0.99)). Compared to the radiological ankle centre, the mean midpoint of the malleoli was 2.3 mm (SD 1.3) lateral and 5.2 mm (SD 2.4) distal, shifting alignment by 0.34. o. (SD 2.4. o. ) valgus, whereas the midpoint of the soft-tissue sulcus was 4.69 mm (SD 3.55) lateral and 32.4 mm (SD 12.4) proximal, shifting alignment by 0.65. o. (SD 0.55. o. ) valgus. On the intermalleolar line, measuring a point at 46% (SD 2%) of the intermalleolar width from the medial malleoli (2.38 mm medial adjustment from midpoint) resulted in knee alignment identical to using the radiological ankle centre. Conclusion. The current study leveraged AI to create a consistent and objective model that can estimate patient-specific adjustments necessary for optimal landmark usage in extramedullary and computer-guided navigation for tibial coronal alignment to match radiological planning. Cite this article: Bone Jt Open 2022;3(10):767–776

Our work is based on the analysis of 104 patients with suppurative posttraumatic osteoarthritis of the ankle joint. By prolonged septic arthritis with degradation of articular surfaces of ankle and shin bones we used necrectomia with osteoarthrotomy and compression arthrodesis in the mechanism of external fixation, which allows to radically sanify the nidus of infection and eliminate the inflammatory process all together. This operation was performed for 68 patients. Surgical treatment for 18 patients with septic arthritis of the ankle joint with considerable involvement of ankle joint metaepiphysis was performed in the following way. We performed segmental resection of the shin bone distal part, put in external fixation mechanism with the possibility of defect building, and then we performed the osteotomy of the shin bone in its upper one-third. On the 10th day we started performing building of defect by Ilizarov. For six patients with ankle joint septic arthritis with considerable involvement of ankle bone we performed its subtotal resection and compression arthrodesis in the external fixation mechanism. For patients with total overall affection of the ankle bone we performed ankle bone excision and tibialcalcaneal fusion. For three patients we performed ankle bone excision with tibialcalcaneal fusion and external fixation. For nine patients where it was not possible to perform a single-stage fusion of shin and heel bones we used external fixation mechanism with the possibility to move the shin bone fragment. Then we performed open fusion of shin and heel bones. The result was considered to be position (92% of patients) in case of extremity support ability recovery, suppurative process elimination and bony ankylosis achievement. Original ankle joint injury nature and localization are very important in selecting the necessary surgical treatment variant. Differential surgical treatment tactics selection for patients with suppurative ankle joint osteoarthritis together with adequate usage of conservative therapy allow to eliminate active purulo-necrotic process and restore the extremity support function for most patients

Background. Total Ankle Replacement (TAR) has become a common surgical procedure for severe Osteoarthritis of the ankle. Unlike hip and knee, current TARs still suffer from high failure rates. A key reason could be their non-anatomical surface geometry design, which may produce unnatural motion and load-transfer characteristics. Current TARs have articular surfaces that are either cylindrical or truncated cone surfaces following the Inman truncated cone concept from more than 60 years ago [1]. Our recent study demonstrated, that the surfaces of the ankle can be approximated by a Saddle-shaped, Skewed, truncated Cone with its apex directed Laterally (SSCL) [2]. This is significantly different than the surface geometry used in current TAR systems. The goal of this study was to develop and test the reliability of an in vitro procedure to investigate the effect of different joint surface morphologies on the kinematics of the ankle and to use it to compare the effect of different joint surface morphologies on the 3D kinematics of the ankle complex. Methodology. The study was conducted on ten cadaver ankle specimens. Image processing software (Analyze Direct. TM. ) was used to obtain 3D renderings of the articulating bones. The 3D bone models were then introduced into engineering design software packages (, Geomagic. TM. and Inventor. TM. ) to produce a set of four custom-fit virtual articular surfaces for each specimen: 1. Exact replica of the natural surfaces; 2. cylindrical; 3. truncated cone with apex oriented medially according to Inman's postulate; and 4. SSCL. The virtual TAR implants were exported to a 3D printing software and 3D physical models of each implant was produced in PLA using 3D printing (Figure 1). The intact cadaver was tested first in a specially design loading and measuring system [3] in which external moments were applied across the ankle in the three planes of motion and the resulting motion was measured through a surgical navigation system (Figure 1). Each of the four customized implant sets were then surgically introduced one at a time and the test was repeated. From the results, the ankle, subtalar and complex kinematics could be compared to that of the intact natural joint. Results and Conclusions. 1. Replacing the natural ankle joint surfaces by artificial exact replicas do not significantly affect the kinematic characteristics thus establishing good reliability of the experimental technique. This high reliability is an important finding proving that the combined factors involved in the process, such as replacing the natural surfaces with artificial replicas and the overall surgical procedure, do not significantly affect the kinematic characteristics of the ankle joint; 2. The SSCL implant produces close to intact joint kinematics (Figure 3), 3. The SSCL produces closer to normal kinematics then TARs with either cylindrical surfaces or those representing a symmetric truncated cone with apex oriented medially (Figure 3). For any figures or tables, please contact authors directly (see Info & Metrics tab above).

Endoprosthetic replacement of the distal tibia and ankle joint for a primary bone tumour is a rarely attempted and technically challenging procedure. We report the outcome of six patients treated between 1981 and 2007. There were four males and two females, with a mean age of 43.5 years (15 to 75), and a mean follow-up of 9.6 years (1 to 27). No patient developed a local recurrence or metastasis. Two of the six went on to have a below-knee amputation for persistent infection after a mean 16 months (1 to 31). The four patients who retained their endoprosthesis had a mean musculoskeletal tumour society score of 70% and a mean Toronto extremity salvage score of 71%. All were pain free and able to perform most activities of daily living in comfort. A custom-made endoprosthetic replacement of the distal tibia and ankle joint is a viable treatment option for carefully selected patients with a primary bone tumour. Patients should, however, be informed of the risk of infection and the potential need for amputation if this cannot be controlled

The posterolateral approach to ankle joint is well suited for ORIF of posterior malleolar fractures. There are no major neurovascular structures endangering this approach other than the sural nerve. The sural nerve is often used as an autologous peripheral nerve graft and provides sensation to the lateral aspect of the foot. Hence every attempt must be made to protect the sural nerve. The aim of this paper is to measure the precise distance of the sural nerve from surrounding soft tissue structures. This is a retrospective image review study including patients with MRI of their ankle from January 09 - Nov 2010. We indentified 78 MRI scans out of which 64 were deemed eligible for assessment. All measurements were made from Axial T1 slices. Measurements were made from the lateral aspect of the TA to the central of the sural nerve, central of sural nerve to the posterior aspect of the peronei muscles and central of the sural nerve to the posterior aspect of fibula. Data were collected on a Microsoft Excel spreadsheet and the descriptive statistics calculated. The key findings of the paper is the safety window for the sural nerve from the lateral border of TA is 7mm, 1.3cm and 2cm at 3 cm above ankle joint, at the ankle joint and at the distal tip of fibula respectively. Similarly the safety window for the nerve from the posterior aspect of fibula is 2cm, 1.6cm, 1.6cm at 3cm above ankle, at the ankle joint and the distal tip of fibula respectively. Our study demonstrates the close relationship of the nerve in relation to tendoachilles, peronei and fibula in terms of exact measurements. The safety margins established in this study should enable the surgeon in preventing endangerment of the sural nerve encountered in this approach

The technique of the transfibular approach for arthrodesis of the ankle joint is described. The results of this operation in a series of thirty cases shows that the procedure is reliable if the technique is carried out faithfully. The two cases in which a first operation failed can both be explained by errors of technique or after-treatment

Purpose of the study: Stiffness of the ankle joint is a common complication after fracture, surgical repair, or total ankle arthroplasty. Dorsiflexion is generally the most limited movement. A few older papers have focused on this common problem in orthopaedic surgery of the ankle joint but have been controversial. The purpose of this anatomy study was to evaluate the efficacy and quantify the impact of releasing the collateral ligaments of the ankle joint on dorsiflexion stiffness. Material and methods: The two main ankle ligaments implicated in this type of stiffness, the deep bundle of the posterior tibiotalar ligament (dPTTaL) and the posterior talofibular ligament (PTaFL), were studied. We dissected 16 talocrural joints on fresh cadavers and measured with electronic goniometry coupled with electronic dynamometry their movement in dorsiflexion after section of the dPTTaL in the first group and after section of the PTaFL in the second. Results: The results showed a significant difference (p< 0.0003) between the two populations of ankles. Section of the dPTTaL was more effective against dorsiflexion stiffness than section of the PTaFL, even though the overall benefit in dorsiflexion was less than 10° (mean 7.45 versus 3.45). Combined section of the two ligaments did not provide a statistically significant improvement in the gain in dorsiflextion (p=0.88) compared with isolated section of the two ligaments. Discussion: If limitation of active and passive dorsiflexion persists after classical release or lengthening of the posterior periarticular tendons of the ankle joint, or after gastrocnemius lengthening, our results show that the following surgical step could be meticulous release of the dPTTaL

Introduction This study aims to improve knee arthroplasty prosthetic alignment by determining if an algorithm based on establishing the most prominent points on the medial and lateral malleolion 3D CT scans can be used to establish the true center of the ankle joint. Methods Axial, coronal and sagittal multi-planar reconstructions were generated on 20 ankles. Two observers independently identified the most prominent medial and lateral malleolar points, in the coronal plane, and the highest talar dome point, in the sagittal plane. Ratios were calculated comparing total intermalleolar distance to distance to medial and lateral malleolus, and the ratio of medial to lateral distance. The distance from the true center of the joint, in the sagittal plane, to the computer calculated center was determined. Statistical analysis using ANOVA, paired t-tests and regression analysis was performed. There were 17 normal ankles, two arthritic ankles, and one previously fractured ankle. Results In the coronal plane there was a strong correlation between the measurements of each observer. The mean intermalleolar distance was 70.2 mm (95% CI 68.3–72.0). The strongest correlation was seen in the ratio of lateral distance to total distance (r=0.728) which was 0.57 in normal ankles (95% CI 0.55–0.58). The ratio for arthritic ankles was 0.48 (95% CI 0.46–0.50) and for the fractured ankle 0.57 (95% CI 0.15–0.99). These were significantly different at the five percent level (p< 0.02). The normal ankle ratio was substantiated by regression analysis. There was a poor correlation between the individual measurements in the sagittal plane (r=0.218). The mean distances from the calculated line to the true center were not statistically different with the true center always lying posterior to the calculated line (4.2 mm (95% CI 2.5–5.9) and 2.8 mm (95% CI 1.7–3.8) posterior. For the combined data this means that the mean distance that the true center of the ankle joint’s from a line joining the medial and lateral malleoli is 3.2 mm (95% CI 2.3–4.0 mm). The data was reproducible with a small standard deviation in each plane. Assuming a 300 mm tibial length, angular error in tibial alignment generated by a computer navigation system is less than one degree in both planes. Conclusions The algorithm presented can give accurate measurements of normal ankle joints in knee navigation surgery

To study the effect of ligament injuries and surgical repair we investigated the three-dimensional kinematics of the ankle joint complex and the talocrural and the subtalar joints in seven fresh-frozen lower legs before and after sectioning and reconstruction of the ligaments. A foot movement simulator produced controlled torque in one plane of movement while allowing unconstrained movement in the remainder. After testing the intact joint the measurements were repeated after simulation of ligament injuries by cutting the anterior talofibular and calcaneofibular ligaments. The tests were repeated after the Evans, Watson-Jones and Chrisman-Snook tenodeses. The range of movement (ROM) was measured using two goniometer systems which determined the relative movement between the tibia and talus (talocrural ROM) and between the talus and calcaneus (subtalar ROM). Ligament lesions led to increased inversion and internal rotation, predominantly in the talocrural joint. The reconstruction procedures reduced the movement in the ankle joint complex by reducing subtalar movement to a non-physiological level but did not correct the instability of the talocrural joint

The ankle joint offers adverse conditions to any prosthetic replacement: high loads on small surfaces, only vague landmarks for the insertion, complex and individually very different functional anatomy. Despite these obstacles many excellent short- and some long-term results have been published, giving little way to a learning curve. This contrasts with our own experiences over at all 29 years now: 24 % failures of cemented two-component EP’s after 14,6 (6,1–21,2) years (n=67) and 8,7 % failures of uncemented tri-component EP’s after 3,7 (0,6–7,6) years (n=92). We analyze and explain special problems and typical failures by a brief historical review of ankle joint replacement: as a logical sequence of various concepts, each of them basing on the knowledge of preceding insufficiencies. The general concern of the functionally useful, but limited mobility after the implantation will be discussed, also on the basis of own early and medium-term results: ROM ranging on average from 26° for TPR-(n=35) and 29° for New Jersey LCS-(n=30) up to 35° for S. T. A. R.-prostheses (n=12). Possible solutions of problems will be considered, respecting assumed causalities. Basing on the literature and own earlier investigations, especially the long-term results will be compared critically. The incertitude of an exact implantation has been partly compensated by the actual „meniscal“ concept of tricomponent prostheses. It should be favourable for their fixation to the bone and moreover reduce polyethylene-wear. But – as before – the discrepancy of high loads on a small area threatens the durability of ankle joint prostheses. Prosthetic replacement has become indispensable in the treatment of painfully destructed ankle joints, but it demands a careful and critical indication

We present the case of a previously well 18 year old female who presented with an acute onset swollen painful right ankle with an overlying non-blanching purpuric rash. There were no associated systemic features. Ankle joint aspirate grew Neisseria Meningitides. She was treated with intravenous third generation cephalosporin's and surgical washout of the joint with improvement. Primary meningococcal arthritis (PMA) is rare and mostly associated with the knee joint. Presentation of meningococcal disease in this manner is easily missed or misdiagnosed as gonococcal disease or overlying cellulitis. Primary meningococcal arthritis is a rare form of septic arthritis. It can be misdiagnosed as an overlying cellulitis or as a gonococcal rash. Physicians should be aware of the possibility of this microorganism presenting as a septic arthritis, and understand the importance of joint aspiration at the centre of diagnosis

Rotational instability is defined as combined medial and lateral ligament instability of the ankle joint. In the case of combined injury to the posterior syndesmosis and posterior joint portion the typical giving-away-symptoms and the therapy resistant complaints are accompanied. In the following prospective study 43 patients between the ages of 16 and 35 with the average age of 23.9 years with posttraumatic chronic joint-instability as well as posterior syndosmosis insufficiency were examined. The treatment of rotational instability was performed by an anchoring technique modified by Broström. The resulting insufficiency of the posterior syndesmosis was treated by a Tight Rope provided by Arthrex. The study was run over 14 months, where only 36 out of 43 patients were available for postoperative follow up. A preoperative baseline 2-view x-ray as well as an MRI was performed in all patients. The operation to establish the stability of the ligaments via anchoring-technique and the treatment of the posterior syndesmosis through Tight-Rope were performed via arthroscopy of the ankle joint with additional inspection of the posterior joint portion. At the same time existent impingements were recessed. In each patient the AOFAS score as an indicator for the treatement outcome and the VAS-score was used as the measurement for the level of pain developement were used. The first exam was performed in preoperative setting followed by subsequent 12 and 24 weeks as well as 12 and 14 months postoperatively. To ensure stability a preoperative x-ray in suppination stress was performed followed by the same type of x-ray 3 months postoperatively. A significant improvement in the above mentioned scores were noted already 3 months after the operation. An improvement in VAS-score of 5.1 points as well as in AOFAS-score of 79% was observed. The degree of Suppination and rotational movement as well as the extent of talus-forfall has reduced significantly. The already improvement of the above scores after 3-month-follow up were consistent even after 14 months. About 90% of patients were satisfied with the outcome of the operation with the “good” and “very good” scores. The complication rate was about 3%. In conclusion, the treatment of posttraumatic mechanical ankle joint instability with posterior syndesmosis injury via anatomic anchoring reconstructive technique and Tight-Rope is considered to be an operative modality with significantly satisfactory results. Keywords: Rotational instability, posterior syndesmosis, stabilisation, tight-rope

Distal tibial fractures may be satisfactorily held in reduction by fine-wire external fixation techniques, avoiding the need for open reduction and internal fixation. However, as the use of external fixation is associated with pin-site infection, extra-articular placement of the wires is recommended. This study assesses the proximal extension of the capsule of the ankle joint in order to provide information on the safety of wire placement for distal tibia fractures. We recruited 7 patients who were electively scheduled for an MRI ankle investigation with the suspicion of osteochondral defect and/or meniscoid lesion. Patients with a history of ankle fracture or ankle surgery were excluded from the study. Just prior to MRI, the ankle joint was injected with 5 to 15 ml of contrast solution (1 mM dimeglumine gadopentetate). Selected fat-saturated T1-weighted MRI scans with sagittal, coronal and axial views were obtained. The site and proximal extent of the capsular reflection with reference to the anterior joint line were measured. All contrast-enhanced MRIs of the ankle joint space were well defined and unambiguous. Proximal capsular extensions above the plane of the anterior joint line were noted at the antero-medial and antero-lateral aspect of the joint (mean 8.9 mm, range 4.9 to 13.4 mm) and at the tibia-fibular recess (mean 18.7 mm, range 13.3 to 23.6 mm), areas that are frequently traversed by wire insertion. Conclusion: This in vivo contrast-enhanced MRI ankle study demonstrates an appreciable capsular extension above the joint line of the ankle. The proximal capsular extensions at the antero-medial and antero-lateral aspect of the joint and at the tibio-fibular recess run the risk of being traversed during fine-wire placement for distal tibia fractures. Surgeons using these techniques should be aware of this anatomy

Introduction. In a previous study of subjects with no history of lower extremity injury or disease we found a linear relationship between body weight and peak hip, knee, and ankle joint forces during the stance phase of gait. To investigate the effect of total knee arthroplasty (TKA) on forces in the operated joints as well as the other joints of the lower extremities, we tested TKA subjects during gait and performed inverse dynamics analyses of the results. Materials and Methods. TKA subjects (3 M, 1 F; 58 ± 5 years; body mass index range (BMI): 26–36 kg/m. 2. ) participated in this investigation following institutional review board approval and informed consent. One subject had bilateral knee replacement. Each patient received the same implant design (4 PS, 1 CR). Data from previously tested control subjects (8 M, 4 F; 26 ± 4 years; BMI: 20–36 kg/m. 2. ) were used for comparison. Retro-reflective markers were placed over bony landmarks of each subject. A nine-camera video-based opto-electronic system was used for 3D motion capture as subjects walked barefoot at a self-selected speed on a 10 meter walkway instrumented with three force plates. Data were imported into a 12-body segment multibody dynamics model (AnyBody Technology) to calculate joint forces. Each leg contained 56 muscles whose mechanical effect was modeled by 159 simple muscle slips, each consisting of a contractile element. The models were scaled to match each subject's anthropometry and BMI. For the control subjects, only one limb was used in determining the relationship between body mass and peak joint force at the hip, knee, and ankle. For the TKA subjects, the peak joint forces were calculated for both the TKA limb and the contralateral limb. Results. Figure 1 shows the knee joint forces for the TKA subjects’ operated (red triangles) and contralateral knees (diamonds) along with the values for the control subjects (circles). Knee joint forces for the TKA subjects fell within or near the upper and lower 95% confidence intervals (dashed lines) of the mean regression lines (solid lines) for the control subjects. Three patients had other lower limb complications (osteoarthritis, ankle surgery). One subject favored the operated limb and another the non-operated limb, as ascertained from the corresponding hip (Figure 2) and ankle joint forces (Figure 3). Discussion. Modeling and simulation can be used to indirectly estimate joint forces in the implanted and non-operated joints. Our gait-lab derived inverse dynamics simulations suggest that joint forces following TKA fall within or near the normal range over a wide range of body weights and that the linear dependence between joint force and body weight applies to the implanted as well as non-implanted joints

Aims: The purposes of the current retrospective study were to evaluate the outcome of a consecutive series of supramalleolar osteotomies and to identify the influence of the technique (opening versus closing wedge) on the outcome and the union rate. Methods: In a five year period, we performed a supra-malleolar osteotomy for the correction of distal tibial mechanical malalignment of at least 10°, with concomitant pain and with or without radiographic evidence of arthritic changes, or as an alternative to other common procedures, for the treatment of a small group of patients with degenerative changes of the ankle joint. Results: There were 14 patients (15 feet) with an average follow up of 31.1 months. All osteotomies healed at an average time of 13.6 weeks. The average AOFAS score improved from 53.8 to 87 points, the average Takakura score from 56.7 to 82 and the average pain score from 13.5 to 31.4. In the presence of deformity the average values of TAS and TLS angles were significantly improved. The radiographic degenerative changes in the ankle joint showed no evidence of progression. The choice of technique did not influence the clinical- radiographic outcome and the healing time of the osteotomy. Conclusions: Supramalleolar osteotomy is a useful procedure to: a. reconstruct the normal mechanical environment in malunion preventing or decelerating any long term deleterious effects and improving pain and function levels, and b. to shift and redistribute loads in the ankle joint in an effort to protect the articular cartilage from further degenerative process

Aims: The arthrodesis is a method of selection at a purulent destruction of a talocrural joint. By loss of motions the pain and the deformation are eliminated, capacity of a load of an extremities is restored. Methods: We allocate by experience of treatment 73 ill with a chronic infection of an ankle joint, which one executes in period with 1976 for 2002 an arthrodesis of a talocrural joint with applying of apparatus of external þxation. The external þxator consists of 2 rings on the anticnemion and 2 semirings on the foot. On the foot a pin was passed through talus, which provided maximum rigid of þxation and created conditions for early mobilization of a subtalar joint. At destruction of talus or distal metaphysis of a tibial is executed the autospongioid osteal plasty for 15 ill, which one has allowed to keep an axis of an extremity without shortening one. Results: The follow-up for 65 ill are studied in terms from 1 till 25 years. The osteal ankylosis is reached in 63 cases; the resistant remission of infected process is reached in 59 cases. Conclusions: Thus an arthrodesis of a ankle joint by the apparatus of external þxation enables to avoid the many-stage treatment, to reach an ankylosis in minimum terms and to restore function of an extremity

Background

Lateral ankle instability is a common problem, but the precise role of the lateral ankle structures has not been accurately investigated. This study aimed to accurately investigate lateral ankle complex stability for the first time using a novel robotic testing platform.

Aims: The purposes of the current retrospective study were to evaluate the outcome of a consecutive series of supramalleolar osteotomies and to identify the inßu-ence of the technique (opening versus closing wedge) on the outcome and the union rate. Methods: In a þve year period, we performed a supramalleolar osteotomy for the correction of distal tibial mechanical malalign-ment of at least 10¡, with concomitant pain and with or without radiographic evidence of arthritic changes, or as an alternative to other common procedures, for the treatment of a small group of patients with degenerative changes of the ankle joint. Results: There were 14 patients (15 feet) with an average follow up of 31.1 months. All osteotomies healed at an average time of 13.6 weeks. The average AOFAS score improved from 53.8 to 87 points, the average Takakura score from 56.7 to 82 and the average pain score from 13.5 to 31.4. In the presence of deformity the average values of TAS and TLS angles were signiþcantly improved. The radiographic degenerative changes in the ankle joint showed no evidence of progression. The choice of technique did not inßuence the clinical- radiographic outcome and the healing time of the osteotomy. Conclusions: Supramalleolar osteotomy is a useful procedure to: a. reconstruct the normal mechanical environment in malunion preventing or decelerating any long term deleterious effects and improving pain and function levels, and b. to shift and redistribute loads in the ankle joint in an effort to protect the articular cartilage from further degenerative process

Aim To characterise the mechanical properties of the ankle, it is essential to have accurate joint morphology and measurements of the cartilage thickness and its variation across the joint. Thickness and volume measurements are also useful tools for detecting and monitoring degenerative change, however baseline measurements are required, to act as a ‘gold standard’. We present details of ankle cartilage thickness and distribution over the entire ankle joint, using a high precision stereophotogrammetry system. Method Twelve cadaveric ankles surfaces with photo targets, rigidly attached, were imaged using a stereo-photographic system, which generates a dense 3D point cloud of co-ordinates on the surface (typically 70,000 points per surface, accuracy ±2 μm). After imaging the surface, the cartilage was dissolved using 5% sodium hypochlorite to reveal the subchondral bone and the process was repeated. The two surfaces were combined and the normal distance from cartilage surface to bone was calculated at every point on the cartilage surface. Results The mean cumulative cartilage thickness of the ankle joint was 1.18±0.23 mm, the mean maximum cumulative cartilage thickness of the entire ankle joint was 2.17±0.46 mm. When considering the cartilage layers of the talus and the tibia-fibula complex separately, the mean and mean maximum thickness for the talus was 1.17±0.18 mm and 2.12±0.54 mm respectively. For the tibia-fibula complex, the mean and mean maximum thickness was 1.18±0.28 mm and 2.3±0.57 mm respectively. 3D cartilage thickness maps were also produced. Conclusion The cartilage maps show that the thickest cartilage occurs at the shoulders of the talus, as opposed to the talar dome, as reported in earlier studies, which were unable to assess the highly curved regions of the ankle. This method also provides a gold standard for validating MRI cartilage measurements

Aim of study: To assess ankle dorsiflexion of operated pedes equinovari congenitales in both clinical examination and gait analysis. Introduction: Mac Kay subtalar release corrects mostly perfectly deformed feet. Operated feet show however stiffness not only in subtalar but as well as in ankle joint. The range of motion in ankle joint was not yet studied systematically at all. Gait analysis offers the possibility to follow the motion in ankle joint dynamically. Material: Thirty six consecutively operated feet were examined by clinical as well as by gait analysis examination. All were operated by Mac Kay procedure at least one year before examination (range 1–7 years). Feet were examined in lying and stance positions. Gait analysis was based on use of Oxford foot model (8 cameras motion capture system). Results: Dorsiflexion/plantiflexion of the foot estimated by clinical examination was compared with maximum dorsiflexion in phase of mid-stance (second rocker)/maximum plantiflexion in pre-swing phase (third rocker). Differences individually for each patients in dorsiflexion/plantiflexion were calculated. Mean of difference between dorsiflexion in clinical examination and dorsiflexion in gait analysis x = 14.3°. Mean of diference between plantiflexion in clinical examination and plantiflexion in gait analysis x= 5,4°. Using T-paired test these differences were found statistically significant (p=0,01). Normal maximum dorsiflexion of the children’ foot in gait analysis is about 20°. From this point 14 operated feet out from 36 did not fulfill this criterion. On the other hand only 4 operated feet showed in gait analysis dorsiflexion less than 10°. Discussion: Dorsiflexion of the foot is important for smooth gait. The diference between dates from clinical examination and dates from gait lab can be explained by weight - bearing force pushing the foot into dorsiflexion during second rocker or by secondary adaptive intrinsic bending of the foot. Conclusion: Operated feet showed moderate/severe stiffnes of ankle joint. Despite of it, the gait cycle was not significantly impaired

Introduction: Pain is the key symptom of patients suffering of osteochondral lesion (OCL) of the ankle. However, its tissue origin and the pain inducing and modulating mechanisms remain controversial. Cartilage is aneural and unlikely causing pain. Contrary soft and bone tissue show rich nociceptive innervations. Routine radiographic imaging of OCL fails to visualize the pain inducing structure. Recent studies demonstrated the capability of planar scintigraphy and SPECT for localizing painful joints in degenerative joints conditions. However, a limited spatial resolution of bone scans compromises an accurate anatomical localization of an uptake. Single photon emission computed tomography – computed tomography (SPECT-CT) is a new hybrid imaging technique allowing perfect overlay of functional and anatomical images. In OCL, SPECT-CT identifies the exact location of an OCL and determines the spatial extent of pathological bone remodeling. We conducted a study to evaluate the correlation between pathological uptake within an OCL and pain experienced by patients. Methods: 15 patients (7 female, 8 male; mean age 39, range 20–61 years) were assessed for unilateral OCL of the talus (13 joints) or distal tibia (2 joints). Radiological imaging of the foot and ankle consisted of plain radiographs, MRI and SPECT-CT. Clinical examination included range of motion (ROM), AOFAS Ankle-Hind-foot Scale, and pain status measured by the visual analogue scale (VAS). On completion of radiological and clinical assessment, patients were referred to the interventional radiology department for a diagnostic ankle injection. CTguided ankle joint injection with local anesthetics and iodine contrast medium was performed. Exact location of the deposit was documented. VAS score was assessed immediately post-infiltration and compared to the pre-interventional VAS score. Pain relief was defined as a reduction of VAS score of more than 50% of the pre-intervention score immediately after infiltration. The study was approved by the institutional review board and written informed patient consent was obtained. The study was carried out in accordance with the World Medical Association Declaration of Helsinki. Results: All infiltrations were technically successful. Pre-interventional VAS score was 5.3 (range 2 - 10; SD 2.33). Post-interventional VAS score was 1.1 (range 2 – 4; SD 1.45). This difference was statistically significant (p < 0.01). Discussion: The results of our study show a highly significant correlation between pain in OCL and pathological uptake seen on SPECT-CT, indicating bone as a major contributor to pain in this disease. Hybrid SPECT-CT technique is a new and powerful approach to diagnosis and staging of osteochondral lesions and provides important data for adequate treatment

1. Sixty feet operated upon either by triple or pantalar tarsal fusion for instability after poliomyelitis were re-examined ten to twenty-four years later. 2. After triple fusion with preservation of the ankle joint there was a striking absence of late osteoarthritis of the ankle, and only a low incidence of troublesome lateral instability of the ankle. The results were generally good provided the patient had reasonable power of extension of the knee. 3. Triple arthrodesis for completely flail foot in patients without active muscle control of the knee was often disappointing, so far as the limb as a whole was concerned, because of a persistent flexion deformity of the knee which usually necessitated the wearing of an appliance. 4. The results of pantalar arthrodesis for the flail foot were satisfactory. When this operation was performed (with the foot in slight equinus) in patients who lacked active extension of the knee it helped to stabilise the knee in walking by encouraging hyperextension

Introduction. The ankle cartilage has an important function in walking movements, mainly in sports; for active young people, between 20 and 30 years old, the incidence of osteochondral lesions is more frequent. They are also more frequent in men, affecting around 21,000 patients per year in USA with 6.5% of ankle injuries generating osteochondral lesions. The lesion is a result of ankle sprain and is most frequently found in the medial location, in 53% of cases. The main objective of this work was to develop an experimental and finite element models to study the effect of the ankle osteochondral lesion on the cartilage behavior. Materials and Methods. The right ankle joint was reconstructed from an axial CT scan presenting an osteochondral lesion in the medial position with 8mm diameter in size. An experimental model was developed, to analyze the strains and influence of lesion size and location similar to the patient. The experimental model includes two cartilages constructed by Polyjet™ 3D printing from rubber material (young modulus similar to cartilage) and bone structures from a rigid polymer. The cartilage was instrumented with two rosettes in the medial and lateral regions, near the osteochondral region. The fluid considered was water at room temperature and the experimental test was run at 1mm/s. The Finite element model (FE) includes all the components considered in the experimental apparatus and was assigned the material properties of bone as isotropic and linear elastic materials; and the cartilage the same properties of rubber material. The fluid was simulated as hyper-elastic one with a Mooney-Rivlin behavior, with constants c1=0.07506 and c2=0.00834MPa. The load applied was 680N in three positions, 15º extension, neutral and 10º flexion. Results. The experimental strain measured in the cartilage in the rosettes presents similar behavior in all experiments and repetitions. The maximum value observed near the osteochondral lesion was 3014(±5.6)µε in comparison with the intact condition it was 468 (±1.95)µε. The osteochondral lesion increases the strains around 6.5 times and the synovial liquid reduces the intensity of strain distribution. The numerical model presents a good correlation with the experiments (R2 0.944), but the FE model underestimates the values. Discussion and conclusion. As a first conclusion, the size of the osteochondral lesion is important for the strains developed in cartilage. The size of lesion greater than 10mm is critical for the strains concentration. The synovial fluid present an important aspect in the strains measured, it reduces the strains in the external surface of cartilage and induces an increase in the lower part. This phenomenon should be addressed in more studies to evaluate this effect

1. Three children with metatarsus adductus varus have been found to have ball and socket ankle joints. 2. The effect of this finding on treatment is discussed

Introduction

Temporary spanning fixation aims to provide bony stability whilst allowing access and resuscitation of traumatised soft-tissues. Conventional monolateral fixators are prone to half-pin morbidity in feet, variation in construct stability and limited weight-bearing potential. This study compares traditional delta-frame fixators to a circular trauma frame; a virtual tibial ring block spanned onto a fine-wire foot ring fixation.

Aims

To report the outcomes of patients with a fracture of the distal tibia who were treated with intramedullary nail versus locking plate in the five years after participating in the Fixation of Distal Tibia fracture (FixDT) trial.

A high incidence of complications with wound healing in calcaneum fractures treated with open reduction and internal fixation (25 – 33% of cases) has been reported. In one study 80% of those who had wound complications required surgical treatment of these. Two recent studies have shown that the risk factors for wound complications in this injury are single layered closure, high BMI, extended time between injury and surgery, diabetes, open fractures and smoking. In our unit, out of a small sample of 56 patients undergoing calcaneal fracture fixation, all those who developed wound complications were smokers. Transcutaneous oximetry is a technique that has been used routinely to assess oxygen perfusion in neonates and also sometimes in peripheral vascular disease (PVD). It has seen greater use as a research tool in PVD and orthopaedic surgery, being used to look at oxygenation around wounds to assess different surgical approaches. This study was performed to assess whether a difference in the oxygen perfusion around the ankle joint could be measured in smokers and non-smokers. A transcutaneous oximetry probe was used to assess the tissue oxygen perfusion at the ankle (posterior to lateral malleolus where the incision line would be) and on the chest (just to the side of the sternum). A standardised technique was used for each patient. Patients were chosen who had no lower limb orthopaedic problem or known PVD. The groups were matched in terms of sex and average age. The data was analysed after logarithmic transformation using a two-tailed Students t-test. The average pO2 chest/foot ratio was higher in the non-smokers than smokers but this was not significant (p=0.704). The average ankle pO2 was higher in the non-smokers and this was shown to be significant (p=0.026). Although a small sample, these data suggest that tissue oxygenation around the ankle may be significantly lower in smokers. This would help to explain why they are at increased risk of wound healing complications. This work also demonstrates that transcutaneous oximetry can be a useful tool in orthopaedic research. Tissue oxygenation around other joints could also be assessed in relation to position to discover the optimum position for wound healing

Introduction Osteochondral lesions of the talus are a common occurrence especially in sports injuries. The biomechanical nature of the ankle joint makes it susceptible to sprains which can cause damage not only to the capsulo-ligamentous structures, but also to the joint cartilage and subchondral bone. As it is known, joint cartilage is a highly specialized and multitask tissue. Because joint cartilage has poor reparative capability, damage may be irreversible and as a consequence, can also lead to osteoarthritis. The purpose of this study is to review the results of a series of patients treated with autologous chondrocytes implantation (A.C.I.) and to describe the evolution in surgical technique that we have been implemented in the last 8 years. Methods Thirty-nine patients with a mean age of 27 8 years affected by osteochondral lesions of the talus > 1.5 cm2, were treated by autologous chondrocyte implantation. All patients were checked clinically and by MRI up to 4 years follow-up. The first 9 patients received the ACI by open technique and the remaining 30, arthroscopically. In the last 10 patients the cartilage harvested from the detached osteochondral fragment was used for the colture. All patients were checked clinically (AOFAS score), radiographically and by MRI, before surgery, at 12 months and at follow-up. Eleven patients underwent a second arthroscopy with a bioptic cartilage harvest at 1 year follow-up. Samples were stained with Safranin-O and Alcian Blue. Immunohistochemical analysis for collagen type II was also performed. Results Before surgery the mean score was 48.4 17 points, at 12 months 90.9 12 (p< 0.0005), while at follow up was 93.8 8 (p< 0.0005) demonstrating an improvement over time. The histological and immunohistological analyses performed on the cartilage samples using Safranin-O, Alcian Blue staining and anti-human collagen type II antibody respectively showed a typical cartilage morphology, were positive for collagen type II and for proteoglycans expression. Conclusions The clinical and histological results have confirmed the validity of the technique utilized, with laboratory data confirming the newly formed cartilage was of hyaline type for all the cases evaluated

We will present the results of our different studies from 1979 till now. Between 1979 and 1984 we tested 1120 consecutive patients with distorsion trauma by stress x-rays, taking only the anterior drawer sign. 237 patients (21, 2 %) were treated operatively because of pathological instability. The correlation: operative findings/positive anterior drawer sign was 85 %. Because of our prospective study in 19 84: arthrography versus x-ray in 52 patients we abandoned the invasive arthrography because it did not give better information about the instability of the ankle. After an investigation of 42 patients with instable ankle joints in our and in the university hospital of Kuopio treated by Evans operation in 1983 with the outcome 42% anteriorly instable, 26% pain at the insertion point at metatarsus V, we looked for a better reconstruction method. We chose our own method, anatomical reinsertion of FTA and FC, and augmentation of FTA with half of syndesmosis anterior.20 patients, who were treated with this anatomical reconstruction technique(group A), and 20 patients, who underwent primary repair (group B), were controlled 2–4 years after operation. We reviewed 15 patients from group A and 17 from group B. Functional scores were good in both groups without significant difference and no difference in the mean talar translation between the two groups. In a second investigation -92–93 with 43 primary ligament repairs and 31 reconstructions, 89% were active athletes. The outcome after 2–4years was 2, 3% of primary repaired ankles were still painful vs. 22,6 of ankles in delayed reconstruction group. Improvement of anterior stress radiography 3,9mm of those with ligament repair and 1,5 mm of those with reconstructive procedures. This difference between these two groups was significant. Should we operate primarily or treat the patients adequately-air cast, active rehabilitation and only persisting instability by operation with an anatomic reconstruction??

Several emerging reports suggest an important involvement of the hindfoot alignment in the outcome of knee osteotomy. At present, studies lack a comprehensive overview. Therefore, we aimed to systematically review all biomechanical and clinical studies investigating the role of the hindfoot alignment in the setting of osteotomies around the knee.

A systematic literature search was conducted on multiple databases combining “knee osteotomy” and “hindfoot/ankle alignment” search terms. Articles were screened and included according to the PRISMA guidelines. A quality assessment was conducted using the Quality Appraisal for Cadaveric Studies (QUACS) - and modified methodologic index for non-randomized studies (MINORS) scales.

Three cadaveric, fourteen retrospective cohort and two case-control studies were eligible for review. Biomechanical hindfoot characteristics were positively affected (n=4), except in rigid subtalar joint (n=1) or talar tilt (n=1) deformity. Patient symptoms and/or radiographic alignment at the level of the hindfoot did also improve after knee osteotomy (n=13), except in case of a small pre-operative lateral distal tibia- and hip knee ankle (HKA) angulation or in case of a large HKA correction (>14.5°). Additionally, a pre-existent hindfoot deformity (>15.9°) was associated with undercorrection of lower limb alignment following knee osteotomy. The mean QUACS score was 61.3% (range: 46–69%) and mean MINORS score was 9.2 out of 16 (range 6–12) for non-comparative and 16.5 out of 24 (range 15–18) for comparative studies.

Osteotomies performed to correct knee deformity have also an impact on biomechanical and clinical outcomes of the hindfoot. In general, these are reported to be beneficial, but several parameters were identified that are associated with newly onset – or deterioration of hindfoot symptoms following knee osteotomy. Further prospective studies are warranted to assess how diagnostic and therapeutic algorithms based on the identified criteria could be implemented to optimize the overall outcome of knee osteotomy.

Remark: Aline Van Oevelen and Arne Burssens contributed equally to this work

Aim of study: Comparison of clinical and radiological results of the applied methods. Material and method: 20 patients with osteochondritis dissecans of the talus were treated. Autologous chondrocyte transplantation was applied to a group of 10 patients (Group A) and autologous osteochondral transplantation to the rest 10 patients (Group B).Group A: Average-age=30,8 years, -follow up time= 33,6 (12–48) months, -lesion size= 20×16,2 (35–15 × 25–15) mm and depth =7 (20–5) mmGroup B: Average –age =33, 7 years, follow up time =32,4 (12–48) months, – lesion size=16,5×15 (25–10 × 20–10) mm and depth=4 (5–3) mm.All patients underwent clinical und radiological investigation and the symptoms were classified in accordance with the Finsen classification. Group A was treated with autologous chondrocyte and Group B with autologous osteochondral transplantation. Osteotomy of the medial or lateral malleolus was necessary by 6 Group A – patients and 4 Group B – patients. Postoperative treatment : Non-weight bearing for 6 weeks, continuous passive motion of the joint, clinical and radiological follow up 3rd, 6th, 12th and yearly basis. Results: Postoperatively the average Finsen score showed for Group A an improvement from 3,5 (very bad) to 1,1 (excellent) and for Group B from 3,6 (very bad) to 1 (excellent). MRI follow up showed defect coverage by 7 patients of Group A and 9 patients of Group B after 12 months. Second look arthroscopy was performed by 4 patient of Group A and 3 patients of Group B showing full coverage of the defect site. Complications: persisting swelling for an average time of 2,7 months in Group A and 4,3 months in Group B. Additionally 10 degrees loss of joint extension in 4 patients of Group A and 3 patients of Group B. Conclusion: Autologous chondrocyte transplantation as well as autologous osteochondral transplantation present very good clinical results. As methods of articular surface restoration they have their advantages and disadvantages playing an important role in chosing one of them, in combination always with the surgeons philosophy. The existence of these methods is important in influencing the course of the ankle joint towards a good prognosis, in cases of osteochondral lesion. Further investigation is necessary

Introduction: Chronic anterolateral instabilitiy of the ankle joint is a combination of mechanical and functional instability. Various surgical procedures are well known. Many of them are peroneus brevis tenodesis techniques. We demonstrate our modified surgical procedure (Peroneus-brevis-shift technique) as well as report results from 2 to 17 years post operatively, as short-, mid-, and long-term results. OP-technique: The intact peronaeus brevis tendon is shifted and sutured fronto-lateral of the malleolus lateralis in neutral polsition of the foot. Postoperatively full weight bearing without a blaster is allowed, a splint for 3 weeks is recommended. Patients and Methods: From 11/86 to 12/04 91 patients (95 feet) were treated with our modified peroneus brevis tenodesis augmentation. Preoperatively all patients were treated conservatively without success. Following surgical treatment all patients under went a standardised post operative treatment protocol. In this retrospective study 73 patients (81,1%) resp. 77 feet (81%) with a meantime follow up of 9.3 ± 4.7yrs were available for evaluation. Patients were evaluated using the following means, clinical examination (AOFAS ankle-hindfood scale of H. Kitaoka), function score (Karlsson and Peterson), instability score (Good et al), radiological examination (according to Van Dijk et al), and dynamometric testing. All clinical and radiological tests were done on the treated and non treated sides (control group). We evaluated the results of our clinical testing as well as biplanar stress radiographs, using the TELOS device (15kp), with regards to talar shift and talar tilt. Dynamometric examination of both feet was performed and force descrepencies between the operated and non-operated sides was eveluated with regards to eversion force. Statistical testing were performed concerning short-, mid-, and long-term Results: (Kruskal-Wallis-tests and chi-squared-tests). All p-values < 0.0015625 were considered as statistically significant. The critical boundary results from the correction for multiplicity due to the number of tests (32 tests were performed, 0,05/32=0.0015625). Results: Short- (2–5yrs), mid- (6–10yrs) and long-term (11–17yrs) results showed no statistically significant differences in any clinical or radiological testing between the treated and control side. Discussion: In many cases of chronic lateral instability of the ankle also a strain of the lateral talocalcaneal joint is seen. Most tenodesis techniques are showing the well known biomechanical disadvantages more or less. Our peroneusbrevis-shift technique (PBS-technique) offers a simple and safe surgical technique, a short learning curve and early weightbearing stability. It leads in 93% to excellent and good longterm results

Background: Neglected ruptures of the tendoachilles pose a difficult surgical problem. Intervening scar tissue has to be excised which cannot be repaired by end-to-end anastamosis. Several techniques for reconstruction of chronic ruptures have been described. The flexor hallucis longus (FHL) tendon transfer is considered advantageous over other tendon transfers. One disadvantage of FHL is it has limited excursion. There are no data to determine the optimal positioning of the FHL tendon to the calcaneum. Materials and Methods: Two computer programmes (MSC.visualNastran Desktop 2002™ and Solid Edge® V19 were used to generate a human ankle joint model. This model is able to reproduce dorsi- and plantarflexion. Different attachment points of FHL tendon transfer to the calcaneum were investigated. Results: The lowest muscle force to produce plantarflexion (single stance heel rise) was 1355N. Plantarflexion increased for a more anterior attachment point. The maximal plantarflexion was 33.4° for anterior attachment and 24.4° for posterior attachment. There was no significant difference in these figures when the attachment point was moved to either a medial or lateral position. Clinical relevance: Optimal FHL tendon transfer positioning is a compromise between achieving plantarflexion for normal physiological function versus the force generating capacity and limited excursion of FHL. A more posterior attachment point is advantageous in terms of power. The range of motion is 10° less than when attachment is more anterior, the arc of motion (24.4°) is still physiological. We recommend that FHL is transferred to the calcaneum in a posterior position

The axis of the talo-crural joint was analysed by roentgen stereophotogrammetry in eight healthy volunteers. Examinations were performed at 10 degrees increments of flexion and pronation/supination of the foot as well as medial and lateral rotation of the leg. Results indicate that the talo-crural joint axis changes continuously throughout the range of movement. In dorsiflexion it tended to be oblique downward and laterally. In rotation of the leg, the axis took varying inclinations between horizontal and vertical. All axes in each subject lay close to the midpoint of a line between the tips of the malleoli. Our study indicates that the talo-crural joint axis may alter considerably during the arc of motion and differ significantly between individuals. This prompts caution in the use of hinge axes in orthoses and prostheses for the ankle.

This paper reports fifteen cases of ball and socket articulation at the ankle followed up for an average of twelve years. All patients showed inequality of leg length. Ten patients showed coalitions of the bones of the hindfoot and nine patients had a reduction in the number of bony elements of the forefoot. Other associated anomalies are described. The abnormality seems to be part of a congenital short-limb malformation, perhaps modified by adaptive change associated with rigidity of the hindfoot. Surgical intervention was not required in any patient in the series.

1. Partial diastasis of the tibio-fibular syndesmosis is believed to be common, but it is often overlooked as a cause of recurrent sprains of the ankle.

2. The treatment of recurrent sprains of the ankle by stabilising the inferior tibio-fibular joint with a lag screw is described. The method has been used in seventy-five patients aged between sixteen and sixty-five years. The longest follow-up has been six years.

We present the results of ankle fusion using the Ilizarov technique for bone loss around the ankle in 20 patients. All except one had sustained post-traumatic bone loss. Infection was present in 17. The mean age was 33.1 years (7 to 71). The mean size of the defect was 3.98 cm (1.5 to 12) and associated limb shortening before the index procedure varied from 1 cm to 5 cm. The mean time in the external fixator was 335 days (42 to 870). Tibiotalar fusion was performed in 19 patients and tibiocalcaneal fusion in one. Associated problems included diabetes in one patient, pelvic and urethral injury in one, visual injury in one patient and ipsilateral tibial fracture in five. At the final mean follow-up of 51.55 months (24 to 121) fusion had been achieved in 19 of 20 patients. A total of 16 patients were able to return to work. The results were graded as good in 11 patients, fair in six and poor in three. The mean external fixation index was 8.8 days/mm (0 to 30). One patient with diabetes developed severe infection which required early removal of the fixator. Refractures occurred in three patients, two of which were at the site of fusion and one at a previous tibial shaft fracture site. Equinus deformity of the ankle fusion occurred after a further fracture in one patient. There were two patients with residual forefoot equinus, and one developed late valgus at the fusion site.

Poor consolidation of the regenerated bone in two patients was treated by bone grafting in one and by bone and fibular strut grafting in the other. Residual soft-tissue infection was still present in two patients.

Introduction: Qualitative evaluation of postoperative outcome in cartilage repair techniques is an issue due to morbidity of bioptic second look. T2 mapping is becoming increasingly popular in the knee, providing information about the histological and biochemical contents of healthy or reparative tissue. Nevertheless, little is known about its applicability to the ankle due to thinner cartilage layer.

Aim of this study was to investigate the validity of T2 mapping in ankle cartilage characterization.

Materials and Methods: 20 healthy volunteers and 30 patients affected by osteochondral lesions of the talus and previously treated by different cartilage repair techniques, were evaluated by T2 mapping. Reparative procedures included microfractures, Autologous Chondrocyte Implantation (open or arthroscopic) and Bone Marrow Derived Cell’s Transplantation. DPFSE with or without fat suppression, T2FSE with or without fat suppression, 3D SPGR and T2-Mapping using a dedicated phased array coil and 1.5 T MR scanner were used as MRI acquisition protocol.

MRI results were correlated with clinical score (AOFAS) in the cases who received a cartilage reconstruction treatment.

Results: A statistically significant correlation (p< 0.05) was shown between MRI and clinical results. A reduced mean T2 value, suggestive for fibrocartilage features, was shown at repair sites in microfractures, whereas no significative differences with healthy hyaline cartilage mean T2 value, were found in other repair techniques with good to excellent clinical score.

Conclusions: T2 mapping demonstrated to be adequate in characterizing cartilage tissue in the ankle. Further studies are required to implement a tool which may over time be a valuable non-invasive alternative to bioptic evaluation.

Aims: The purpose of this paper is to review a series of ankle post-traumatic deformities treated by arthroplasty, þbula lengthening, bone graft and correction of the malunion. Methods: 30 cases, mean age 40 (±15), were operated 6–30 months after injury and followed up at 5 years. Clinical Maryland foot score (MFS) and X-ray evaluation were performed pre op and at follow up. After medial revision of bone and soft tissue structures, through a lateral transmalleolar approach, mal-union of the posterior malleolus or sinking of the lateral tibial plafond were corrected using autologous cortical cancellous bone graft covered by its periosteal ßap. Postoperative treatment consisted of immediate continual passive motion weightbearing allowed after an average of 8–12 weeks after surgery. Results: Pre op MFS was 64±8 and post-op it was 82±11. 11 patients had excellent results with normal range of motion, no pain, and no progression of the arthritis. The result in 9 cases was good with a normal range of motion, little pain after long walk, and no progression of arthritis. 7 cases were fair because of a decrease in the range of motion and progression of arthritis and moderate pain. 3 poor cases needed arthrodesis. Conclusions: Fibula lengthening, bone graft and correction of malunion were effective treatment of ankle post-traumatic valgus deformity in order to delay ankle fusion in young patients. The success of the procedure was correlated to the severity of arthritis and the joint congruity obtained by surgery.

The purpose of this study is to demonstrate the validity of the autologous chondrocytes transplantation (A.C.T.) technique implemented over the last 6 years in the treatment of osteochondral lesions of the talus.

Our case study included 22 patients (12 males and 10 females), with an average age of 27 years affected by osteochondral lesions of the talus surface. All lesions were > 1.5 cm2, monofocal, and post-traumatic in origin. The first 9 patients received ACT (Genzyme technique) and the remaining 13 patients received ACT with an arthroscopic technique. In 6 of the patients, the cartilage harvested from the detached osteochondral fragment was used for culturing, avoiding the first step arthroscopy in the knee. Before surgery, all patients were assessed clinically, radiographically, and using MRIs. For clinical evaluation patients were assessed using the American Foot & Ankle Society 100 point score. Before surgery the mean score was 48.4 points. 11 patients underwent second-look arthroscopy at one year during which a biopsy was harvested for histologic analysis of the reconstructed cartilage. Of these, 9 patients (Genzyme technique) also had hardware removed.

The mean follow-up of the 22 patients was 36 months. At follow-up, all patients but one were satisfied with their results. With regards to the clinical results evaluated using the American Foot and Ankle Society score, an average of 90.5 was obtained at 24 months, while at 36 months the average score (19 patients) was 94.0 (range 54–100). During follow-up arthroscopy, 4 patients had mild fibrosis and 1 patient required regularization of flap overgrowth causing pain.

The clinical and histological results have confirmed the validity of the surgical technique utilized with no subjective nor objective complications. An improvement of the symptoms and of articular function has also been observed: laboratory data confirmed the histological appearance of the newly formed hyaline cartilage in all cases evaluated. Immunohistochemistry showed a positive staining for collagen type II located in the extracellular matrix and in the chondrocytes in the healthy and transplanted cartilage biopsies. All the specimens studied were also positive for proteoglycans expression as was the Alcian blue reaction, which highlighted the presence of these fundamental components of a cartilaginous matrix.

Problem: There are known numberous surgical treatments for problems of arthrotic ankle-joints. Recently there is comeing up more and different kind of arthroplasty. The overall aim is to create good axis, stable situation and full weight-bearing situation without pain for a long time.

Our technique is a single anterior surgical aproach and internal fixation with 2 cannulated percutaneous titanium screws.

This procedure allowes both in young active persons and in cases after failed surgery a good and recomendable solution with early weight-bearing and durable results without following surgery.

Method and Results: We present our follow up results of 40 Patients in paired samples tests and VAS at minimum 24 month.

Difficult revisionsurgery and degenerative cases are shown in pictures. Cases of Revision after Arthroplasty are done.

Facit: In our hands this procedure is the standard procedure. We can reach the aim of good, safe and longterm standing results. The biomechanical positioning is mandatory. The overuse of following joints is not clinicly relevant and reduceable by wearing adapted shoes.

Even in cases of revisionsurgery after arthroplasty the modification with “malleolus lateralis-Interposition” is a good possbility to reach functionally good results without loosing height at safe softtissue.

The Australian National Joint Replacement Registry is now one of the largest of its kind in the world with over 420,000 surgeries having been collected. Of these the majority are THR and TKR. Recently replacements of the shoulder, elbow, wrist and ankle (TAJR) have been included on the registry and we already have approxi-mately200 TAJR on the registry. It is anticipated that within 4 years we should be able to provide TAJR sur-vivorship data that will be world class. For this to occur it will mean that revision surgeries of any kind will need to be tracked which will not automatically occur unless an implant is changed or removed. As revision surgeries could involve conversion to an arthrodesis, gutter clearance, ligament stabilization, subtalar arthrodesis, treatment of malleolar fractures or realignment hindfoot procedures the AOA member must notify the registry of such events for the data set to be a true indication of the performance of any particular prosthesis.

The aim of this presentation is to promote discussion on what secondary interventions the registry will need to be notified of and what processes will need to be established so the additional data can be verified by the registry.

Aim

The aim of this study was to compare the diagnostic accuracy of the Magnetic Resonance Imaging with that of Stress views of the ankle in testing the integrity of the lateral ankle ligaments. Arthroscopic diagnosis was used as the gold standard.