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
Aims . To assess the effect of high tibial and distal femoral osteotomies
(HTO and DFO) on the pressure characteristics of the
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
Aims: To identify the distraction forces and contact pressures of the
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
Aims. Accurate identification of the
Our work is based on the analysis of 104 patients with suppurative posttraumatic osteoarthritis of the
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
Endoprosthetic replacement of the distal tibia and
The posterolateral approach to
The technique of the transfibular approach for arthrodesis of the
Purpose of the study: Stiffness of the
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
To study the effect of ligament injuries and surgical repair we investigated the three-dimensional kinematics of the
The
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.
Rotational instability is defined as combined medial and lateral ligament instability of the
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
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
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
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
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. A six degrees of freedom robot manipulator and a universal force/torque sensor were used to test 10 foot and ankle specimens. The system automatically defined the path of unloaded plantar/dorsi flexion. At four flexion angles: 20° dorsiflexion, neutral flexion, 20° and 40° of plantarflexion; anterior-posterior (90N), internal-external (5Nm) and inversion-eversion (8Nm) laxity were tested. The motion of the intact ankle was recorded first and then replayed following transection of the lateral retinaculum, Anterior Talofibular Ligament (ATFL) and Calcaneofibular Ligament (CFL). The decrease in force/torque reflected the contribution of the structure to restraining laxity. Data were analysed using repeated measures of variance and paired t-tests.Background
Method
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
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
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
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
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
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
1. Three children with metatarsus adductus varus have been found to have ball and socket
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. The two cohorts were compared for demographics and fracture patterns. The quality of initial reduction and the maintenance of reduction until definitive surgery was assessed by two authors and categorised into four domains. Secondary measures included fixator costs, time to definitive surgery and complications.Introduction
Materials and Methods
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. The FixDT trial reported the results for 321 patients randomized to nail or locking plate fixation in the first 12 months after their injury. In this follow-up study, we report the results of 170 of the original participants who agreed to be followed up until five years. Participants reported their Disability Rating Index (DRI) and health-related quality of life (EuroQol five-dimension three-level questionnaire) annually by self-reported questionnaire. Further surgical interventions related to the fracture were also recorded.Aims
Methods
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
Introduction Osteochondral lesions of the talus are a common occurrence especially in sports injuries. The biomechanical nature of the
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
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
Introduction: Chronic anterolateral instabilitiy of the
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
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.
Aim of this study was to investigate the validity of T2 mapping in ankle cartilage characterization.
MRI results were correlated with clinical score (AOFAS) in the cases who received a cartilage reconstruction treatment.
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.
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.
Difficult revisionsurgery and degenerative cases are shown in pictures. Cases of Revision after Arthroplasty are done.
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.
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. This was a prospective study involving 45 patients who had previous trauma to the ankle and reported symptoms of ankle instability. Our patients were recreational athletes or military patients. These patients had MRI evaluation prior to arthroscopic evaluation and treatment of the ankle. The diagnosis regarding the integrity of the Calcaneofibular ligament (CFL) and the Anterior Talo-fibular ligament (ATFL), as obtained from the MRI was compared against the assessment of integrity from the stress views. These were compared against the assessment made by direct visualisation of the ligaments during arthroscopy. The sensitivity, specificity, negative (NPV) and positive predictive values (PPV) and accuracy were then calculated.Aim
Methods