Osteotomies in the musculoskeletal system are joint preserving procedures to correct the alignment of the patient. In the lower limb, most of the pre-operative planning is performed on full leg weightbearing radiographs. However, these images contain a 2-dimensional projection of a 3-dimensional deformity, lack a clear visualization of the joint surface and are prone to rotational errors during patient positioning.
Accurate evaluation of lower limb coronal alignment is essential for effective pre-operative planning of knee arthroplasty.
Background.
One-fourth of all ankle trauma involve injury to the syndesmotic ankle complex, which may lead to syndesmotic instability and/or posttraumatic ankle osteoarthritis in the long term if left untreated. The diagnosis of these injuries still poses a deceitful challenge, as MRI scans lack physiologic weightbearing and plain weightbearing radiographs are subject to beam rotation and lack 3D information.
Introduction:. Cone Based CT (CBCT) scanning uses a point source and a planar detector with parallel data acquisition and volumetric coverage of the area of interest. The pedCAT (Curvebeam USA) scanner is marketed as a low radiation dose, compact, faster and inexpensive CT scanner that can be used to obtain both non- weightbearing and true 3 dimensional weightbearing views. Method:. A review of the first 100 CBCT scanning in our unit has been performed to assess ease of scanning, imaging time, radiation dose and value of imaging as opposed to conventional imaging. Results:. A pedcat CT scan was available within minutes of the request, similar to plain radiographs but much earlier than a 6 week delay for a patient to attend a new appointment for a conventional CT. All patients returned to see the clinician for a clinical decision in the same NHS clinic and did not require a new clinic visit; illustrative cases include fracture/subluxation detection, surgical planning, extent of arthritis and 3D assessment of union of arthrodeses. All patients were able to transfer to the scanner with ease and the imaging time was 10 times than a conventional CT. The radiation dose to the patients was 9% that of a full gantry system.
The most important determinant in the treatment of malleolar fractures is stability. Stable fractures have an intact deep deltoid ligament and do not displace with functional treatment. If the deep deltoid/medial malleolar complex is disrupted, the talus is at risk of displacement. Weber (2010) showed that weightbearing radiographs predicted stability in patients with undisplaced ankle fractures. We developed clinical criteria for potential instability and applied them to a prospective series of patients. Criteria included: medial clear space of < 4mm; medial tenderness, bruising or swelling; a fibular fracture above the syndesmosis; a bimalleolar or trimalleolar fracture; an open fracture; a high-energy fracture mechanism. A consecutive, prospectively documented series of 37 patients chose functional brace treatment of potentially unstable fractures.
Acute syndesmotic ankle injuries continue to impose a diagnostic dilemma and it remains unclear whether weighbearing or external rotation should be exerted rotation during the imaging process. Therefore, we aimed to implement both axial load (weightbearing) and external rotation in the assessment of a clinical cohort of patients with syndesmotic ankle injuries syndesmotic using weightbearing CT imaging. In this retrospective comparative cohort study, patients with an acute syndesmotic ankle injury were analyzed using a WBCT (N= 20; Mean age= 31,64 years; SD= 14,07. Inclusion criteria were an MRI confirmed syndesmotic ankle injury imaged by a bilateral WBCT of the ankle during weightbearing and combined weightbearing-external rotation. Exclusion criteria consisted of fracture associated syndesmotic ankle injuries. Three-dimensional (3D) models were generated from the CT slices. Tibiofibular displacement and Talar Rotation was quantified using automated3D measurements (Anterior TibioFibular Distance (ATFD), Alpha Angle, Posterior TibioFibular Distance (PTFD) and Talar Rotation (TR) Angle) in comparison to a cohort of non-injured ankles. The difference in neutral-stressed Alpha° and ATFD showed a significant difference between patients with a syndesmotic ankle lesion and healthy ankles (P = 0.046 and P = 0.039, respectively) The difference in neutral-stressed PTFD and TR° did not show a significant difference between patients with a syndesmotic ankle lesion and healthy ankles (P = 0.492; P = 0.152, respectively). Application of combined weightbearing-external rotation reveals a dynamic anterior tibiofibular widening in patients with syndesmotic ankle injuries. This study provides the first insights based on 3D measurements to support the potential relevance of applying external rotation during WBCT imaging. However, to what extent certain displacement patterns are associated with syndesmotic instability and thus require operative treatment strategies has yet to be determined in future studies.Results
Conclusion
Ankle fractures in the elderly are common and have a mortality rate of 12% within the first year. Treatment is challenging due to osteoporotic bone and patient co-morbidities. Many patients struggle with non-weight-bearing (NWB) and presently there is no consensus in the literature regarding optimum management of these injuries. We hypothesised that early weight-bearing in frail patients, Clinical Frailty scale (CFS) score of 4 or more will reduce morbidity and allow patients to return to their usual place of residence faster without jeopardising clinical outcome. We conducted a retrospective analysis of 80 patients aged over 65 years managed at Fiona Stanley Hospital for ankle fractures between January 2016 and 2018. Patients were divided into two cohorts: 40 patients managed NWB and 40 who were permitted to weight-bear as tolerated (WBAT). Patients were stratified as fit (CFS 1–3) or frail (CFS 4+). Primary outcomes were one-year mortality, return to primary residence at six weeks and complications. Secondary outcomes included length of acute hospital stay and rehab stay. For frail patients, those managed NWB stayed in rehab for 19 days longer (p=0.03) and had 28% more complications (p=0.03). By 6 weeks, fewer patients returned to full weight-bearing (p=0.03) and fewer patients had returned home (p=0.01). For fit patients, there were no significant differences in primary outcomes between NWB and WBAT. Our novel study categorising patients by CSF demonstrates that early mobilisation in frail patients results in improved outcomes. Currently there is no formal treatment protocol for the management of ankle fractures in the elderly, and we hope that our proposed algorithm will assist surgeons at our institution and elsewhere. Our study suggests that WBAT may benefit frail patients. We propose a protocol to assist in the management of geriatric ankle fracture patients based on clinical frailty scores.
Applications of weightbearing computed tomography (WBCT) imaging in the foot and ankle have emerged over the past decade. However, the potential diagnostic benefits are scattered across the literature, and a concise overview is currently lacking. Therefore, we aimed to systematically review all reported diagnostic applications per anatomical region in the foot and ankle. A systematic literature search was performed in the electronic databases PubMed, EMBASE, Cochrane Library, and Web of Science. Search terms consisted of “weightbearing/standing CT and ankle, hind-, mid- or forefoot”. English language studies analyzing the diagnostic applications of WBCT were included. Studies were excluded if they simulated weightbearing CT, described normal subjects, included cadaveric samples or samples were case reports. The modified Methodological Index for Non-Randomized Studies (MINORS) was applied for quality assessment. The added value was defined as the review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and registered in the Prospero database (CRD42019106980). A total of 48 studies (prospective N=8, retrospective N=36, cohort study N=1, diagnostic N=2, prognostic comparative study N=1) were found to be eligible for review. The following diagnostic applications were identified per anatomical area in the foot: ankle (osteoarthritis N=5, ligament injury N=6); hindfoot (deformity N=9); midfoot (Lisfranc injury N=2, flatfoot deformity N=13, osteoarthritis N=1); forefoot (hallux valgus N=12). The identified studies contained diagnostic applications that could not be used on plain radiographs. The mean MINORS equaled 10.1 on a total of 16 (range: 8 to 12). Diagnostic applications of weightbearing CT imaging are most frequently studied in hindfoot deformity, but other area's areas are on the rise. Post-processing of images was identified as the main added value compared to WBRX. However, the findings should be interpreted with caution as the average quality score was moderate. Therefore, future prospective studies are warranted to consolidate the role of WBCT in diagnostic and therapeutic algorithms.
The aim of this study was to investigate the effect of different loading scenarios and foot positions on the configuration of the distal tibiofibular joint (DTFJ). Fourteen paired human cadaveric lower legs were mounted in a loading frame. Computed tomography scans were obtained in unloaded state (75 N) and single-leg loaded stand (700 N) of each specimen in five foot positions: neutral, 15° external rotation, 15° internal rotation, 20° dorsiflexion, and 20° plantarflexion. An automated three-dimensional measurement protocol was used to assess clear space (diastasis), translational angle (rotation), and vertical offset (fibular shortening) in each foot position and loading condition. Foot positions had a significant effect on the configuration of DTFJ. Largest effects were related to clear space increase by 0.46 mm (SD 0.21 mm) in loaded dorsal flexion and translation angle of 2.36° (SD 1.03°) in loaded external rotation, both versus loaded neutral position. Loading had no effect on clear space and vertical offset in any position. Translation angle was significantly influenced under loading by −0.81° (SD 0.69°) in internal rotation only. Foot positioning noticeably influences the measurement when evaluating the configuration of DTFJ. The influence of the weightbearing seems to have no relevant effect on native ankles in neutral position.
Pes cavovarus is a foot deformity that can be idiopathic (I-PC) or acquired secondary to other pathology. Charcot-Marie-Tooth disease (CMT) is the most common adult cause for acquired pes cavovarus deformity (CMT-PC). The foot morphology of these distinct patient groups has not been previously investigated. The aim of this study was to assess if morphological differences exist between CMT-PC, I-PC and normal feet (controls) using weightbearing computed tomography (WBCT). A retrospective analysis of WBCT scans performed between May 2013 and June 2017 was undertaken. WBCT scans from 17 CMT-PC, 17 I-PC and 17 healthy normally-aligned control feet (age-, side-, sex- and body mass index-matched) identified from a prospectively collected database, were analysed. Eight 2-dimensional (2D) and three 3-dimensional (3D) measurements were undertaken for each foot and mean values in the three groups were compared using one-way ANOVA with the Bonferroni correction.Introduction
Methods
Syndesmotic ankle injuries are present in one fourth of all ankle trauma and may lead to chronic syndesmotic instability as well as posttraumatic ankle osteoarthritis. The main challenge remains distinguishing them from other types of ankle trauma. Currently, the patient's injured and non-injured ankles are compared using plain radiographs to determine pathology. However, these try to quantify 3D displacement using 2D measurements techniques and it is unknown to what extent the 3D configuration of the normal ankle syndesmosis is symmetrical. We aimed to assess the 3D symmetry of the normal ankle syndesmosis between the right and left side in a non- and weightbearing CT. In this retrospective comparative cohort study, patients with a bilateral non-weightbearing CT (NWBCT; N=28; Mean age=44, SD=17.4) and weight-bearing CT (WBCT; N=33; Mean age=48 years; SD=16.3) were analyzed. Consecutive patients were included between January 2016 and December 2018 when having a bilateral non-weightbearing or weightbearing CT of the foot and ankle. Exclusion criteria were the presence of hindfoot pathology and age less than 18 years or greather than 75 years. CT images were segmented to obtain 3D models. Computer Aided Design (CAD) operations were used to fit the left ankle on top of the right ankle. The outermost point of the apex of the lateral malleolus (AML), anterior tubercle (ATF) and posterior tubercle (PTF) were computed. The difference in the coordinates attached to these anatomical landmarks of the left distal fibula in the ankle syndesmosis with respect to right were used to quantify symmetry. A Cartesian coordinate system was defined based on the tibia to obtain the direction of differences in all six degrees of freedom. Statistical analysis was performed using the Mann-Whitney U test to allow comparison between measurements from a NWBCT and WBCT. Reference values were determined for each 3D measurement in a NWBCT and WBCT based on their 2SD. The highest difference in translation could be detected in the anterior-posterior direction (Mean APNWBCT= −0.01mm; 2SD=3.43/Mean APWBCT=−0.1mm; 2SD=2.3) and amongst rotations in the external direction (Mean APNWBCT=−0.3°; 2SD=6.7/Mean APWBCT=-0,2°; 2SD=5.2). None of these differences were statistically significant in the normal ankle syndesmosis when obtained from a NWBCT compared to a WBCT (P>0.05). This study provides references values concerning the 3D symmetry of the normal ankle syndesmosis in weightbearing and non-weightbearing CT-scans. These novel data contribute relevantly to previous 2D radiographic quantifications. In clinical practice they will aid in distinguishing if a patient with a syndesmotic ankle lesion differs from normal variance in syndesmotic ankle symmetry.
To systematically review the literature regarding post-surgical treatment regimens on ankle fractures, specifically whether there is a benefit to early weightbearing or early mobilization (6 weeks form surgery). The PubMed, MEDLINE and Embase databases were searched from inception to May 24, 2020. All randomized controlled trials that analyzed the effects of early weightbearing and mobilization following an ankle surgery were included. The primary outcome measure was the Olerud Molander Ankle Score (OMAS). Secondary outcomes included return to work (RTW) and complications. Logistic regression models with random intercepts were used to pool complication data by protocol clustered by study. Twelve RCT's were included, with a total of 1177 patients (41.8 ± 8.4 years). In total, 413 patients underwent early weightbearing and early mobilization (35%), 338 patients underwent early weightbearing and delayed mobilization (29%), 287 patients underwent delayed weightbearing and early mobilization (24%), and 139 patients underwent delayed weightbearing and delayed mobilization (12%). In total, 81 patients had a complication (7%), including 53 wound complications (5%), 11 deep vein thromboses (1%), and 2 failures/nonunions (0%). Early ankle mobilization resulted in statistically significant increases in OMAS scores compared to delayed mobilization (3 studies [222 patients], 12.65; 95% CI, 7.07-18.22; P < 0.00001, I2 = 49%). No significant differences were found between early and delayed weightbearing at a minimum of one-year follow-up (3 studies [377 patients], 1.91; 95% CI, −0.73-4.55, P = 0.16, I2 = 0%). Patients treated with early weightbearing and early mobilization were at higher odds of facing any complication (OR 3.6, 95%CI 1.05-12.1, p=0.041) or wound complications (OR 4.9, 95%CI 1.3-18.8, p=0.022) compared to those with delayed weightbearing and delayed mobilization. Early mobilization following surgical treatment for an ankle fracture resulted in improved ankle function scores compared to delayed mobilization regimens. There were no significant differences between early and delayed weightbearing with respect to patient reported outcomes. Patients who were treated with early mobilization and early weightbearing had an increased odds of postoperative complications.
Pixel Value Ratio (PVR) is a radiographic measure of the relative density of the regenerate to the adjacent bone. This has been reported as an objective criterion for regenerate healing and a guide for when to allow full weight bearing (FWB) in lengthening with intramedullary telescopic nails. The threshold for which magnitude of PVR is adequate to allow bearing full weight is not yet agreed. The aim of this study was to identify from our cohort of adult limb lengthening patients the time to FWB following lengthening, the PVR at this point, and how this compared with the recommended values in the literature. A retrospective database review identified 30 adult patients treated with the PRECICE femoral nail by two senior authors. Time from completion of lengthening to instruction to fully weight bear was noted. The PVR was calculated for each cortex on plain radiographs taken at each postoperative visit following completion of lengthening. Significance was set at Introduction
Materials and Methods
Lower limb mechanical axis has long been seen as a key to successful in lower limb surgery, including knee arthroplasty. Traditionally, coronal alignment has been assessed with weight-bearing lower limb radiographs (LLR) allowing assessment of hip-knee-ankle alignment. More recently CT scanograms (CTS) have been advocated as a possible alternative, having the potential benefits of being quicker, cheaper, requiring less specialist equipment and being non-weightbearing. To evaluate the accuracy and comparability of lower limb alignment values derived from LLR versus CTS.Abstract
Background
Objectives
Osteosynthesis of high-energy metaphyseal proximal tibia fractures is still challenging, especially in patients with severe soft tissue injuries and/or short stature. Although the use of external fixators is the traditional treatment of choice for open comminuted fractures, patients' acceptance is low due to the high profile and therefore the physical burden of the devices. Recently, clinical case reports have shown that supercutaneous locked plating used as definite external fixation could be an efficient alternative. Therefore, the aim of this study was to evaluate the effect of implant configuration on stability and interfragmentary motions of unstable proximal tibia fractures fixed by means of externalized locked plating. Based on a right tibia CT scan of a 48 years-old male donor, a finite element model of an unstable proximal tibia fracture was developed to compare the stability of one internal and two different externalized plate fixations. A 2-cm osteotomy gap, located 5 cm distally to the articular surface and replicating an AO/OTA 41-C2.2 fracture, was virtually fixed with a medial stainless steel LISS-DF plate. Three implant configurations (IC) with different plate elevations were modelled and virtually tested biomechanically: IC-1 with 2-mm elevation (internal locked plate fixation), IC-2 with 22-mm elevation (externalized locked plate fixation with thin soft tissue simulation) and IC-3 with 32-mm elevation (externalized locked plate fixation with thick soft tissue simulation). Axial loads of 25 kg (partial weightbearing) and 80 kg (full weightbearing) were applied to the proximal tibia end and distributed at a ratio of 80%/20% on the medial/lateral condyles. A hinge joint was simulated at the distal end of the tibia. Parameters of interest were construct stiffness, as well as interfragmentary motion and longitudinal strain at the most lateral aspect of the fracture. Construct stiffness was 655 N/mm (IC-1), 197 N/mm (IC-2) and 128 N/mm (IC-3). Interfragmentary motions under partial weightbearing were 0.31 mm (IC-1), 1.09 mm (IC-2) and 1.74 mm (IC-3), whereas under full weightbearing they were 0.97 mm (IC-1), 3.50 mm (IC-2) and 5.56 mm (IC-3). The corresponding longitudinal strains at the fracture site under partial weightbearing were 1.55% (IC-1), 5.45% (IC-2) and 8.70% (IC-3). From virtual biomechanics point of view, externalized locked plating of unstable proximal tibia fractures with simulated thin and thick soft tissue environment seems to ensure favorable conditions for callus formation with longitudinal strains at the fracture site not exceeding 10%, thus providing appropriate relative stability for secondary bone healing under partial weightbearing during the early postoperative phase.
We evaluated the effect of weightbearing on the results of measurements and decision making by expert evaluators. Twenty one expert foot & ankle surgeons were given weightbearing and nonweightbearing anteroposterior plain foot films of patients with Background
Materials and Methods
The 130 feet were divided into 2 groups. Group I was without TMT 1 – compression screw (n= 60) and group II with an additional compression-screw (n=70). Average age of group I was 54-years. The average age of group II was 50-years. The American-Orthopaedic-Foot and Ankle Society (AOFAS) Forefoot-Score, Visual-analog-pain-scale and foot radiographs were assessed preoperatively and after a mean of 23 months for group I and 39 months for group II. All 130 feet were treated immediately postoperative with a postoperative Darco orthowedge ® shoe.
Using a comparative, longitudinal study design, we studied the effects of early weight bearing and ankle mobilisation following acute repair of ruptured Achilles tendon. Patients in Group 1 (22 males and 4 females; mean age 44.7 years [range 31–69], 11 right- and 15 left-sided ruptures) were immobilised with their ankle in gravity equinus, and encouraged to fully weight bear. They received a single cast change at 2 weeks, when the ankle was accommodated in an anterior splint, allowing full plantarflexion but not dorsiflexion above neutral. Patients in Group 2 (23 males and 4 females; mean age 43.8 years [range 30–67], 11 right- and 16 left-sided ruptures) were immobilised in full equinus. They received a cast change at 2 and 4 weeks, when the ankle was immobilised in a plantigrade position. They were advised to weight bear 4 weeks after the operation. Patients in Group 1 attended less outpatient visits and completely discarded their crutches at an average of 2.5 weeks after the operation. Group 2 discarded their crutches at an average of 5.7 weeks after from the operation (p=0.013). At ultrasound scan, the average thickness of the repaired tendon was 12.1 mm (SD 2), with no difference in the thickness of the ruptured tendon regardless of the method of post-operative management. There was no significant difference in isometric strength between the two groups of patients. A greater proportion of patients in Group 1 were satisfied with the results of surgery (p=0.04). Early weight bearing with the ankle plantigrade is not detrimental to the outcome of repair following rupture of the Achilles tendon, and shortens the time needed for rehabilitation. However, strength deficit and muscle atrophy are not prevented.
Following fixation of proximal femoral fractures in the elderly the operating surgeon may request that the patient be mobilised partially weight bearing on the injured limb. This instruction is most likely if the bone quality is very poor or the fracture pattern unstable, despite evidence that full weight bearing does not affect outcome. 98 elderly patients with proximal femoral fractures treated by either hip screw device, cannulated screws or hemiarthroplasty, who were previously independently mobile, have been followed prospectively to determine their ability to comply with partial weight bearing instructions. A specially designed capacitance foot pressure device was used to determine percentage body weight transferred through the injured limb on mobilising under physiotherapy instruction over 5 days, and factors thought to be predictive of success in partially weight bearing were measured using simple ward tests. 14 patients failed to mobilise independently prior to discharge from hospital and were excluded from further analysis. Of the remaining 84 patients only 24 (28%) successfully managed to partially weight bear 30-50% of their body weight on the injured limb. Only six of those who were unable to partially weight bear on starting to walk after surgery had learnt to do so by the fifth day. Factors indicating success or failure were mental test score, grip strength and straight leg raise on the unaffected side. This study has shown that the majority of elderly hip fracture patients are unable to partially weight bear but, if required, success can be predicted by a few simple ward tests. It is hoped that this information will lead to the more appropriate use of inpatient physiotherapy resources.