Background: First ray instability is known to be responsible for biomechanical changes in the foot leading to several foot disorders. The diagnosis is crucial to determine the treatment strategy, but tends to be based upon the surgeon’s experience and manual sensitivity. This is due to the lack of a practical and reliable instrument to quantify first ray hypermobility. We present a novel electromechanical tool measuring the relative dorsal mobility of the first ray (FRRM) compared with the one of lateral rays, by simulating ground reaction forces during gait. The aim of the study is to assess the intra- and inter-examiners reliabilities of the measurements obtained with this device.
Methods: The protocol includes 2 examiners assessing 22 feet of 11 volunteers (healthy with no history of foot disorder). This device equally applies a standardized, electronically controlled, and precise force under the first metatarsal head M1 as well as under the heads of the lesser metatarsals M2 to M5. The device is equipped with an adjustable heel support based on the patient's foot size. An automated adjustment of the two bearings supporting M1 and M2 to M5 in the transverse plane is performed by two optical sensors. The relative dorsal mobility between these two bearings is then measured as a function of the applied force, ranging from 0 up to 100N. 15 measurements were performed on each foot (3 sets of 5 trials) in order to assess inter- and intra-observer reliability. For this purpose, the interclass correlation coefficient (ICC), the error of measurement (SEM) and the Bland and Altman (B&A) graphical analysis were computed.
Results: Excellent ICC values (≥0.93) were obtained with the novel device for inter-rater (ICC = 0.96, IC95 [0.90-0.98]) and intra-rater reliability (ICC= 0.96, IC95 [0.91-0.99]) when using the FRRM calculation. The mean FRRM values are 5.89±2.34 (mm). The B&A analysis presented a bias between examiners of only −0.12 mm ranging from −0.54 to 0.29 mm.
Conclusion: This study demonstrates the capacity of this device to reliably measure the relative dorsal mobility of the first ray compared with the mobility of lateral rays. It is thus proven to be a reliable tool for proceeding with further studies to define the hypermobility of the first ray more scientifically.
Introduction: Weightbearing computed tomography (WBCT) scans allow for a better understanding of foot alignment in patients suffering from flatfoot deformity (FFD). However, soft tissue integrity (e.g., spring ligament complex or tibialis posterior tendon) cannot be easily assessed via WBCT. As performing both WBCT and magnetic resonance imaging (MRI) might not be cost effective, we aimed to assess whether there is an association between osseous and soft tissue findings in WBCT and MRI.
Methods: In this observational study, a consecutive cohort of 24 patients of various stages of FFD (mean age 51±18 years) underwent WBCT scans and MRI. 24 healthy individuals of similar age, body mass index (BMI) and sex with WBCT scans were used as a control group. In addition to osseous sinus tarsi impingement, four commonly used 3-dimensional (3D) measurements (talo-calcaneal overlap, TCO; talo-navicular coverage, TNC; Meary's angle, MA, axial/lateral) were obtained using a dedicated post processing software (DISIOR 2.1, Finland) on the WBCT datasets. Sinus tarsi obliteration, spring ligament complex, tibiospring ligament integrity, as well as tibialis posterior tendon degeneration were evaluated with MRI. Statistical analysis was performed for significant (P < 0.05) correlation between findings.
Results: None of the assessed 3D measurements correlated with either spring ligament complex or tibiospring ligament tears. Age, BMI, and TCO were found to be associated with tibialis posterior tendon tears. 75 % of patients with sinus tarsi impingement on WBCT also showed signs of sinus tarsi obliteration on MRI. Of the assessed parameters, only age and BMI were associated with sinus tarsi obliteration diagnosed on MRI, while the assessed WBCT based 3D measurements were, with the exception of MA axial, associated with sinus tarsi impingement.
Conclusion: The relationship between WBCT based 3D measurements and soft tissue impairment assessed via MRI is limited. Perhaps not surprisingly, we found partial or complete rupture of the tibialis posterior tendon more likely to occur in comparably older and overweight PCFD patients with an increased TCO. WBCT may not replace MRI and MRI does not replace WBCT regarding their diagnostic value. Both imaging options add different but important information possibly affecting decision-making in the treatment of FFD patients.
Introduction
Knowledge about articular joint mechanics can provide information about altered joint function and potential pathological mechanisms. In silico computational musculoskeletal simulations allow to estimate such contact parameters that cannot be feasibly measured in vivo. To gain insights into articular hindfoot mechanics, the aim of this study was to combine state-of-the-art in vivo 3D motion capture and dynamic in silico musculoskeletal simulations to estimate contact area and pressure of the ankle and subtalar joint in healthy subjects during activities of daily living.
Methods
9 healthy subjects (23±3 years; 23.1±2.0 kg/m2) with no history of foot-ankle injuries were assessed during repeated trials of level walking, stair ascent, and stair descent using a whole body skin-marker set (Boey et al, 2022). Articular joint mechanics were estimated using an extended foot-ankle OpenSim model (Malaquias et al., 2017), with incorporated cartilage geometries of the tibia, talus, and calcaneus. Generic models were scaled for each individual and kinematics calculated for every trial. Marker-based kinematics were then used to estimate articular joint mechanics of the ankle and subtalar joint using the OpenSim joint articular mechanics tool (Smith et al. 2018, Postolka et al. in review).
Results
Throughout the loaded stance phase of all three activities of daily living, mean contact pressures were higher at the ankle (average 2.35-2.93MPa) than at the subtalar joint (average 1.23-1.35MPa). Overall largest contact pressures were found at the ankle joint during stair ascent with peak pressures of 13.7+/-9.2MPa. For the ankle joint, both, contact area and pressure were correlated with ankle plantar/dorsiflexion. For the subtalar joint, however, almost no variations in contact area and pressure were found throughout the three activities of daily living.
Conclusion
By combining a musculoskeletal foot-ankle and contact model, this study provided estimations of articular ankle and subtalar joint contact area and pressure during activities of daily living. This analysis is a first proof-of-concept data set on in vivo articular joint mechanics and can help to gain a more detailed understanding of the relationship between hindfoot motion and loading in healthy individuals.
Acknowledgments
This study was supported by the Swiss National Science Foundation, the Research Foundation Flanders, and the Berghmanns Dereymaeker research Chair on Foot & Ankle Biomechanics.
Objectives: It has been postulated that the screws used in a percutaneous chevron akin procedure should not compress the capital fragment as compression is supposed to change the alignment unfavorably. Not all MIS surgeons have access to these special implants, though. We hypothesize that compression screws are suitable for MICA and can be used without increased risk for hardware failure (loosening, breakage, dislocation), non-union or malalignment.
Material & Methods: Between May 2018 and January 2022, 100 consecutive MICA cases have been performed in a single institution using fully-threaded headless cannulated compression screws (Arthrex FT 4.0 & 3.5mm, Arthrex Inc., Naples /USA). There were 85 female and 15 male patients with a mean age of 53y (range 16-78y). The mean preoperative intermetatarsal angle I/II (IMA) was 15.7°, the mean hallux valgus angle (HVA) 28.7° and the mean distal metatarsal arctiulation angle (DMAA) was 9.4°. All cases were followed at 6 & 12 weeks and 6, 12 & 24 months postop regarding radiologcial correction and surgery-asscoiated comp-lications using a modified Clavien-Dindo classification (CDC).Results: The average amount of radiological correction was 12.6° for IMA and 16.8° for HVA. DMAA was not negatively influenced by the compression screws but improved from a preop mean of 9.4° to 5.5° at latest f/u. Overall, there were four CDC type I complications (oral antibiotics), four type II complications (1x symptomatic osteotomy site displacement, 1x delayed union, 2x transfer metatarsalgia), 23 type III complications consisting of 22x secondary screw removals and 1x superficial wound debridement. All hardware removals were related to the square-headed design. There were no cases of hardware failure requiring revision surgery (no screw loosening, breakage or dislocation).Conclusion: Compression screws are well suited for MICA and provide excellent control of alignment and permanent stabilization. Our surgical technique of 3rd generation MICA is characterized by positioning the distal screw, which crosses the osteotomy site centrally and grasps the MT1 head medially, first. This can help not only to secure but also to improve DMAA.
Compared to bevel-headed screws, a square-headed screw design demonstrated a higher rate of secondary hardware removal due to discomfort at the prominent screw heads. Therefore, the use of bevel-headed screws is strongly recommended, regardless of whether they are compression screws or non-compression.
Introduction
About 10% of malleolar fractures are associated with an injury of the syndesmosis. Syndesmotic compromise is even higher in fractures requiring surgical reduction. Fractures classified as Weber type B and C present up to 40% and up to 80% associated syndesmotic lesions, respectively. A compromise of the syndesmotic ligaments can lead to widening in the ankle mortise, inducing ankle instability, increased risk of early osteoarthritis and chronic pain.
Moreover, the best treatment option for lesions of the tibiofibular syndesmosis remains subject to debate. The most used surgical treatment option is a rigid osteosynthesis by cortical screws. Alternative treatment options are flexible such as the suture-button-technique and k-wire fixation. This latter technique was rarely investigated.
Aim of the study is to assess the patient reported outcome in mid-term.
Methods
We performed a retrospective analysis of 20 consecutive patients who underwent surgical treatment in our center for a bi- or trimalleolar fracture with a K-wire syndesmosis fixation by a single surgeon. After fixation of the lateral and medial malleolus an intraoperative external rotation stress was performed. If a widening of the syndesmosis was confirmed two K- wire were inserted from lateral and caudal to medial and proximal with a 60° divergence angle on the frontal plane.
Patients answered a questionnaire on their functional abilities (EFAS, EFAS sport, SF-12scores) and an AP and lateral ankle X-ray were performed.
Results
The average follow-up of the 20 patients (mean age: 48.3; 15 female, 5 male) was 3.42 years. 55% had an initial dislocated fracture. There was a high energy trauma in 50% of the cases. 45% of the patients had an additional posterior malleolar fracture fixation. At follow-up the mean EFAS score was 22.65 / 24, mean EFAS sport 12.45 / 16, the SF-12: mean MCS was 59.10 and the average PCS 55.45. Anatomic reduction of the fracture was achieved in 70%. Hardware removal was performed in 95% of patients. Nevertheless, there was a 10% complication rate. No patient needed ankle arthrodesis or replacement. Progression of ankle osteoarthritis was not observed in any patient. 67% of patients had osteoarthritis Takakura stage I and 33% stage II.
Conclusion & perspectives
K-wire fixation seems to offer a reliable syndesmosis fixation with good mid-term clinical results and patient satisfaction. It should be discussed as a possible treatment option.
Introduction:
While artificial intelligence (AI) powered applications continue to advance rapidly, the existing literature lacks comprehensive studies on the segmentation of all bones within the human foot using AI. Moreover, conventional manual segmentation of foot bone structures is a time-consuming and labor-intensive task. In this study, we propose a novel approach utilizing deep learning models, specifically convolutional neural networks (CNN), to achieve fully automatic segmentation of every bone in foot scans (CT). Our work aims to provide detailed CT sections of the foot bones, offering precise information on fracture types and enhancing visualization of the limb’s architecture. Thanks to a very fast segmentation process compared to traditional methods, the key benefits of our approach include more accurate diagnosis, more precise fracture analysis, better 3D surgical planning, and optimal post-operative assessment. We firmly believe that the development of such a medical tool will significantly enhance foot-related healthcare, supporting healthcare professionals in their daily practice.
Methods:
We manually segmented foot bones from fifty CT scans. Out of these, forty-eight CT scans were utilized for training the CNN-based segmentation models, while the remaining two CT scans served as the evaluation dataset. We assessed the CNN’s performance in segmenting foot bones using the Dice coefficient and Intersection over Union (IoU) metrics.
Results:
The trained models accurately detected foot bones in the two test samples, achieving an average Dice coefficient of 0.97 and an IoU of 0.94.
Conclusion:
The CNN networks exhibited remarkable proficiency in identifying foot bone structures on CT scans, thereby paving the way for automatic, rapid (within seconds), and highly accurate foot bone segmentation.
Research Question: It is currently a significant challenge to produce and label a sufficient amount of ultrasound (US) data on anatomical structures, including bone surfaces and critical elements like nerves, to enable the training of artificial intelligence (AI) models. We aim to leverage co-registration with other imaging modalities, such as computer tomography (CT), magnet resonance imaging (MRI), and optical systems, to investigate whether an AI-enhanced data annotation approach can be facilitated for US without manual annotations. This study lays the groundwork for enhancing real-time bone registration and identifying key anatomical features like peripheral nerves in foot and ankle operations.
Methods: In this prospective study, we analyzed 14 ex-vivo human leg specimens to compile a detailed dataset for future AI algorithm development. Each specimen was fixed to a wooden model with optical tracker installed. We conducted CT and MRI scans and then collected US images of the sural nerve and the lower leg and ankle bone surfaces. We used an optically-tracked pointer during dissection to sample points along the nerve. Further, the annotated and segmented CT and MRI data were registered with the US images to obtain a multi-modal and automated annotation and segmentation. This processed US data is intended for use as training material for the AI algorithm.
Findings: Early results from our dataset reveal precise alignment between CT and US images for bones and high accuracy in detecting nerves. This accuracy of the multi-modal approach highlights the effectiveness in mapping nerve pathways and aligning bone imaging from CT with US data. These achievements are essential for advancing to the next stage of developing automated, machine learning-based detection and segmentation tools.
Conclusion: In the initial phase of our project, we created a comprehensive dataset from MRI/CT scans, US imaging of nerve and bone structures, dissection, and optical tracking of the sural nerve, achieving precise mapping of CT to US images and detailing the spatial relationship between nerves and bones. Our next research phase aims to develop a proof of concept that applies machine learning to automate and improve the diagnostic process, enhancing the detection of critical anatomical structures for better patient outcomes, reducing neuropathic pain post-surgery and improving the efficacy of minimally invasive surgical techniques.
Introduction
Several demographical and clinical risk factors for recurrent ankle instability have been described. The main objective of this study was to investigate the potential influence of morphological characteristics of the ankle joint on the occurrence of recurrent instability and the functional outcomes following a modified Broström-Gould procedure for chronic lateral ankle instability.
Methods
Fifty-eight ankles from 58 patients (28 males and 30 females) undergoing a modified Broström-Gould procedure for chronic lateral ankle instability between January 2014 and July 2021 were available for clinical and radiological evaluation. Based on the preoperative radiographs the following radiographic parameters were measured: talar width (TW), tibial anterior surface angle (TAS), talar height (TH), talar radius (TR), tibiotalar sector (TTS), ankle mortise angle (AMA). The history of recurrent ankle instability and the functional outcome using the Karlsson Score were assessed after a minimum follow-up of 2 years.
Results
Recurrent ankle instability was reported in 14 patients (24%). The TTS was significantly lower in patients with recurrent ankle instability (69.8 degrees vs 79.3 degrees) (P < .00001). The multivariate logistic regression model confirmed the TTS as an independent risk factor for recurrent ankle instability (OR = 1.64) (P = .003). The receiver operating characteristic curve analysis revealed that patients with a TTS lower than 72 degrees (= low-TTS group) had an 82-fold increased risk for recurrent ankle instability (P = .001). The low-TTS group showed a significantly higher rate of recurrent instability (58% vs 8%; P = .0001) and a significantly lower Karlsson score (65 points vs 85 points; P < .00001).
Conclusion
A smaller TTS was found to be an independent risk factor for recurrent ankle instability and led to poorer functional outcomes after a modified Broström-Gould procedure.
Introduction:
Literature trends indicate a generally lower rate of reoperation and revision associated with the fixed-bearing two-component design implant compared to the mobile-bearing three-component design for total ankle arthroplasty (TAA). Coronal deformity is also linked to poorer outcomes following TAA. The aim of this study was to assess the impact of intra-articular coronal deformity (non-concentric ankle arthritis) on both fixed and mobile implant designs. We hypothesized that non-concentric ankle arthritis and mobile bearings would be associated with a higher revision rate.
Methods:
This study retrospectively reviewed 202 patients who underwent TAA with either mobile-bearing or fixed-bearing implants at three centers in Switzerland by two surgeons between 2007 and 2018. Patients who underwent TAA from 2007 to 2013 received the mobile-bearing implant, while those who underwent TAA after November 2012 received the fixed-bearing implant. The primary outcomes were the rates of revision and reoperation within three years following the initial procedure. Reoperation was defined as any additional surgery post-index surgery, excluding revisions. Non-concentric ankles were identified by a talar tilt angle greater than 4 degrees on preoperative X-rays.
Results:
Of the 76 patients who received a mobile-bearing implant, 33 had non-concentric arthritis, and 43 had concentric arthritis. Of the 126 patients who received a fixed-bearing implant, 61 had non-concentric arthritis, and 65 had concentric arthritis. In the mobile-bearing group, 8 patients underwent revision and 9 underwent reoperation. In the fixed-bearing group, 4 patients underwent revision and 10 underwent reoperation. The revision rate was significantly higher (p < 0.05) for the mobile-bearing implant (15.2%) compared to the fixed-bearing implant (0%) in the non-concentric group. In the concentric group, there was no significant difference in revision rates between the fixed-bearing (6.2%) and mobile-bearing designs (7%).
Conclusion:
The study demonstrated that the use of mobile-bearing implants in patients with non-concentric arthritis is associated with a significantly higher revision rate compared to fixed-bearing implants. In patients with concentric arthritis, there was no significant difference in revision rates between the two implant designs. Additionally, the study found no significant difference in the reoperation rates across all groups.
Introduction
Alignment of the lower limb on plain radiographs is routinely assessed in an orthopaedic practice. The axis of the ankle joint is defined by the medial distal tibial angle (MDTA). The MDTA can be determined using the anatomical, mechanical, or surgical (referring to the tibial tuberosity) tibial axis. Several studies have found variations in measuring the medial distal tibial angle (MDTA), raising questions about current methods.
This study evaluated the three different methods to determine the MDTA on whole lower leg radiographs. The hypothesis predicted clinically significant disparities between the three methods and assessed the reliability of whole lower leg radiographs to measure the ankle joint axis.
Methods
43 eligible patients were recruited from June 2023 to January 2024. Weight-bearing, anteroposterior radiographs were first centred on the ankle joint to obtain a genuine anterior-posterior image (‘mortise view’), then shifted proximally to the centre of the tibial plateau. A stitching tool was used to get a mortise view extending up to the knee. A bead of lead was used to mark the tuberosity. The radiographs were captured twice in each patient to analyse the reliability of the overall approach. The MDTA was measured according to the various definitions in the literature. Two independent examiners measured each angle twice on both radiographs in each patient.
Results
The measurement of the MDTA using the mechanical axis resulted in the same reliability as the established measurement of the MDTA using the anatomical axis. Using the tibial tuberosity as the centre of the proximal tibia resulted in more diverse findings compared to using the method of bisecting the proximal tibia plateau as the tibial centre. Observed differences in MDTA measurements between image pairs could be mainly explained by intra-observer variation, i.e. the ability of observers to measure an MDTA in a reliable manner in a single image. The mean absolute difference between MDTAs across the two images was in the magnitude of 0.8°.
Conclusion
Weight-bearing, whole lower leg radiographs centred on the proximal tibia and ankle joint provide reproducible values for the MDTA. In these images, the clinically important mechanical axis can be determined with the same reliability as the anatomical axis, leading to more options for surgeons to calculate the MDTA. The tibial tuberosity should not be used as a reference to determine the MDTA.
Background:
Pressure distribution in the ankle joint is influenced by various factors, including hindfoot alignment. This study aims to assess the impact of hindfoot alignment on contact pressures in the ankle joint in the setting of supination external rotation (SER) type ankle fractures according to Lauge-Hansen.
Methods:
SER fractures were created in 10 human cadaver lower extremity specimens, creating progressive stages of injury: without fracture (step 0), SER fracture and intact deltoid ligament (step 1), superficial deltoid ligament disruption (step 2), and deep deltoid ligament disruption (step 3). At each step, varus and valgus alignment was simulated by performing an calcaneum osteotomy. Each limb was axially loaded following each osteotomy at a static load of 350N. The center of force (COF), contact area (CA), and peak contact pressure (PP) under load were measured, and radiographs of the ankle mortise were taken to analyze the medial clear space (MCS) and talar tilt (TT).
Results:
The COF (5,3mm; p = 0.030) and the CA (188,4mm2; p=0.015) changed significantly in step 3 in the valgus hindfoot alignment compared to baseline parameters, indicating the importance of deep deltoid ligament integrity in maintaining normal ankle joint contact stress in the valgus hindfoot. These changes were not seen in the setting of varus alignment (COF: 2,3mm, p=0.059; CA: 121mm^2, p=0.133). PP were found to not change significantly in either varus or valgus (varus: p=0.132, valgus p =0.464).
The MCS demonstrated significant widening in step 3 compared to step 0 (0,9mm; p = 0.020) in both varus and valgus hindfoot alignment. In contrast the TT increased significantly in step 3 in the valgus hindfoot (2,8°; p=0.020) compared to step 0.
Conclusion:
SER IV fractures with valgus hindfoot alignment revealed significant changes in pressure distribution and radiographic parameters when compared to SER IV fractures with varus hindfoot alignment. This should be considered in decision making when treating SER fractures in the clinical setting.
Introduction: Ankle osteoarthritis (OA) is predominantly caused by trauma, with common radiological bone changes comprise subchondral bone sclerosis and cyst formation. In this study, we describe the subchondral characteristics associated with secondary ankle OA using a recently developed histological scoring system (Osteoarthritis Bone Score).
Methods: Resection specimens of the distal tibia were harvested from five consecutive patients (3 female, age range [51-83 years]) undergoing ankle arthroplasty for secondary OA due to hemochromatosis (n=1), ligamentous injuries (n=2) and osseous injuries (n=2). Histopathological analyses were conducted on regions-of-interest containing cartilage lesions. Tissue sections were stained with Safranin-O to grade cartilage degeneration using Mankin score (0-14). A novel trichrome staining method (Picrosirius red, Alcian blue, Fast Green) was used to calculate the Osteoarthritis Bone Score (OABS: 0-7) which evaluates presence of cysts, fibrosis, inflammation, cartilage islands as well as trabecular thickening, blood vessel density and tidemark integrity in the subchondral bone.
Results: All specimens displayed severe chondropathy (Mankin score >10), with four out of five samples showing denuded subchondral bone (Mankin score 14). Histopathological features of subchondral bone tissues showed higher intra-patient variability, with high OABS observed in patients with osseous injuries (grade 6) and hemochromatosis (grade 4), and low grades observed in patients with ligamentous injuries (grade 1-3). Interestingly, none of the specimens showed signs of inflammation defined as hypercellular fibrovascular infiltration of marrow spaces. Cartilage islands (endochondral bone formation) and marrow fibrosis were common features among specimens. Osteoid formation, blood vessel density, and thickening of the subchondral cortical plate and trabeculae were increased in high OABS grades (osseous injuries, hemochromatosis) compared to low OABS grades (ligamentous injuries).
Conclusion: Osteoarthritis Bone Scores differed to a greater extent than chondropathy scores in secondary ankle OA. This suggests that subchondral bone changes are a specific feature of OA pathology that is not a mere consequence of cartilage degeneration. Improved understanding of the molecular and cellular changes leading to differential subchondral bone pathology may open new avenues for pharmacological treatment in ankle OA.
Introduction : Our first aim was to compare the long term clinical and radiological outcome of patients sustaining a trimalleolar fracture with a posterior malleolar fragment (PMF) between the patients who had a fixation of the PMF and those who didn’t.
Our secondary aims were to compare the postoperative complication rate, to identify independent risk factors associated with worse clinical and radiological outcome and to assess if the indication of PMF fixation was correlated with the fragment size.
Methods : For this monocentric retrospective comparative study, we included 69 consecutive patients who were operated for a trimalleolar fracture between 2008 to 2013. They completed the SF-12 and the EFAS score at least 10 years after surgery. The radiological osteoarthritis was assessed according to the Kellgren and Lawrence classification. Their demographics (BMI, sex, annual income, smoking status and presence of diabetes) were taken from the chart. The size of the PMF was measured in the preoperative x-ray and the CT and classified according to the Haraguchi classification
Results : 69 patients with trimalleolar fractures were included. 21 (30.4%) of them had a fixation of the PMF by plate and 48 (69.6%) of them had no fixation of the PMF. 49 patients were female (71.01%) and 20 (28.99%) were male. Mean follow-up was 11.3 years. Mean age was 51.4y.o and mean BMI was 26.7. 9 patients (13.04%) had diabetes and 20 patients (29.4%) were smokers. There was no difference between the two group in the long term clinical PROMS (EFAS, SF-12) nor in degree of osteoarthritis (p=0.05). Patients in the fixated PMF group had a higher complications rate (p=0.0004527). In the linear regression analysis diabetes was a predictor of negative outcome for the PCS (p=0.0078) and malreduction of the syndesmosis was a predictor of negative outcome for the EFAS score (p=0.031) and osteoarthritis (p < 0.0001). The PMF size was significantly higher in the fixated group and wasn’t correlated to the long term clinical outcome, except for the mental part of the SF-12 (p=0.029).
There was no significant difference between the two groups in the follow-up surgery rate(p=0.17).
Conclusion & perspectives: Fixation of PMF doesn’t change the clinical and radiological outcome in the long term if the ankle joint is congruent. In contrast the posterolateral approach presents more complications. Surgeons must be aware of this during their design making.
Introduction: Progressive collapsing foot deformity (PCFD) remains a challenge in the treatment of the foot and ankle disorders. Surgical planning hinges on the complexity of the deformity, emphasizing the need for precise differentiation through advanced imaging diagnostics. Traditionally, weightbearing radiographs are employed for PCFD patients. Conversely, the introduction of weightbearing computed tomography (WBCT) has revolutionized the 3D assessment of the deformity. In an effort to better understand how WBCT findings can be integrated in the evaluation of radiographs, we aimed to (1) compare specific X-ray measurements to corresponding WBCT measurements; (2) evaluate the accuracy of X-ray measurements of interest; and (3) investigate whether X-ray measurements can predict osseous impingement in the subtalar joint region identified through WBCT.
Methods: Two clinically established measurements were assessed on standardized weightbearing radiographs (manually) as well as on the WBCT datasets (auto-generated): (1) talo-calcaneal overlap (TCO, mm) and (2) talo-navicular coverage (TNC, °). In addition to the measurements, osseous impingement in the subtalar joint region was assessed on WBCT using three criteria: (1) joint obliteration; (2) cyst formation; and (3) signs of secondary instability. Two of the criteria needed to be fulfilled to confirm subtalar impingement.
Results: While no significant difference between X-ray and WBCT measurements was evident for TCO, significant differences were found for TNC. Inter- and intra-observer reliability was >0.9 for both measurements on X-ray. The mean bias of measurement (between X-ray and WBCT) was 0.2 mm for TCO and -22 degrees for TNC. Cohen’s Kappa for inter- and intra-rater reliability to assess patients for subtalar instability was >0.9. The probability to predict subtalar impingement was ≥0.85 if TCO was >15 mm or TNC was >25 degrees on X-ray.
Conclusion: The examined imaging parameters are reliably assessable through conventional radiographs (TCO/TNC) or weightbearing computed tomography (osseous subtalar impingement). In situations where WBCT is unavailable, X-ray-assessed TCO and TNC can serve as predictors for osseous sinus tarsi impingement. This finding plays a pivotal role in evaluating PCFD patients, aiding in the decision-making process between joint-preserving interventions (e.g., osteotomies) and joint-sacrificing procedures (e.g., realignment fusion) during surgical considerations.
Introduction:
Chronic Achilles tendinopathy with large defects are surgically challenging. Concerns
exist regarding transosseous transfer of the flexor hallucis longus (FHL) tendon due
to the shortened lever arm of flexion and weakening of the big toe. The aim of this
study was to demonstrate the long-term outcome of transosseous FHL transfer for
the treatment of large Achilles tendon defects.
Methods:
We retrospectively analyzed 28 patients who underwent FHL transfer. The extent of
the defect was measured with magnetic resonance imaging before (baseline) and
during the operation. Outcome parameters included the German Foot Function Index
(FFI-D) evaluated at baseline and 6, 12 and 24 months postoperatively, a specific
questionnaire to determine 24-month patient satisfaction, and the documentation of
complications throughout the postoperative course as well as restrictions concerning
plantar flexion strength of the great toe at 24 months.
Results:
Mean baseline FFI-D subscores of pain (37.2) and function (52.3) improved
significantly by 24 months post-surgery with lower mean subscores of 6.9 and 15.0,
respectively (p < 0.001). At 24 months, 57% of patients were very satisfied and 25%
were satisfied since having undergone the procedure. All patients noted a relevant
improvement at the 2-year follow-up with only one stating that while they perceived
the flexion weakness of their big toe, this was not accompanied by any relevant
functional restriction. Lastly, we reported two patients each with minor complications
of delayed wound healing and one patient who experienced a major complication of
severe perifocal wound necrosis during the early postoperative period; the latter
required plastic surgery with an additional skin flap. By the 2-year follow-up, all three
patients were satisfied with their postoperative outcome and free of symptoms.
Conclusion:
This work shows that transosseous FHL transfer is a successful surgical treatment
for large defects of the Achilles tendon. The majority of patients were satisfied with
the outcome of the procedure and experienced a significant improvement in both
function and pain level. Flexion weakness of the big toe does not appear to be a
relevant issue after FHL transfer.
Introduction
Hallux valgus (HV) deformity is one of the most common foot pathologies. Maintaining the correction of the hallux postoperatively is essential for adequate bony and soft tissue healing, notably with the emergence of percutaneous surgery with no osteosynthesis hardware. Current solutions relying on toe spacers and tapes tend to be time-intensive and do not guarantee correction maintenance of the hallux. 3D printed orthoses are advantageous in terms of ease of use and comfort compared to traditional models. This study aims to explore the viability and benefits of employing a personalized foot orthosis in HV patients post-surgery through 3D printing technology.
Methods
Patients scheduled for HV surgery have been prospectively enrolled starting from November 2023. The patients' foot shape was captured preoperatively with the help of a 3D optical scan. The orthosis was numerically designed based on this scan, including a correction of the HV deformity. It features a customizable spacer between the hallux and the second toe (T2) to maintain a proper alignment for optimal bony and soft tissue healing. The orthosis was 3D printed in a flexible thermoplastic polyurethane (TPU). A questionnaire was developed for the assessment of clinical efficacy (wear duration, fit) and patient satisfaction (pain, comfort). The questionnaire was completed by orthopedic surgeons and participating patients during regular follow-ups for up to five weeks post-surgery.
Results
To date, six patients were enrolled, and four patients have been followed up until three to five weeks. All patients reported high overall satisfaction. Two patients noted discomfort due to friction at T2. Therefore, we adapted the design of this area. The device stayed in place while walking. The hallux remained safely stabilized in correct alignment. The orthosis could be easily adapted to oedema thanks to material flexibility and Velcro closure. Its lattice structure allowed for skin breathability. The orthosis was easy to put off and back on, facilitating wound care.
Conclusion
To our knowledge, this is the first description of using a 3D printed orthosis for HV surgery aftercare. The preliminary results suggest it is a reliable and comfortable option with the potential to replace traditional methods. Our ongoing patient inclusion and evaluation will allow us to refine the results. Further studies are required to validate these outcomes and compare them with traditional methods.