Metatarsal pronation has been reported to be a significant recurrence factor for hallux valgus after corrective osteotomies. However, the extent of pronation correction with distal metatarsal I osteotomies varies greatly from patient to patient without the reason being known. The objective of this study was to describe the effect of the metatarsal I osteotomy angle on muscular torque, acting on the first metatarsal. The primary hypothesis was that a varying angle for the transversal cut affects the muscular pronating torque in the first metatarsal. Therefore, three different 3-dimensional foot models have been created, and a distal metatarsal I corrective osteotomy was simulated. The transverse cut of the osteotomy was varied from three different angles (-10°, 0°, 10°). Torque and the pro-/supinating component of eight muscles acting on the first metatarsal have been calculated. No significant difference in pro-/supinating torque acting on the first metatarsal was found between different osteotomy angles. Nevertheless, the lateral shift of the osteotomized metatarsal-I-head in ReveL osteotomy increased supinating torque in almost all analysed muscles, regardless of the angle of the osteotomy. Hence, a tendency (p = 0.082) towards less muscular pronating torque could be shown for all ReveL osteotomies compared to the non-osteotomized status quo. This increased supination was significant especially for the analysed flexors and adductor hallucis caput obliquus.

BACKGROUND:Lateral lengthening calcaneal osteotomy (LLOT, Evans and Hintermann) is widely used to treat progressive collapsing foot deformity (PCFD). In the Evans osteotomy, the cut is performed proximal to the calcaneocuboid joint, carrying a risk of violating the anterior or middle subtalar facet. Hintermann proposed a modified technique placing the osteotomy between the middle and posterior facets to reduce risks. Although anatomical studies have shown potential facet involvement, clinical data on the actual incidence and its impact on long-term outcomes remain scarce. This study aimed to determine the incidence of subtalar facet penetration after LLOT and to evaluate its effect on clinical and radiographic results. METHODS:All patients aged ≥18 years who underwent LLOT (Evans or Hintermann osteotomy) at our institution between January 1, 2010, and December 31, 2020, were included. Postoperative computed tomography (CT) was performed 6 weeks after surgery to assess possible subtalar facet violation. At a minimum follow-up of 5 years, magnetic resonance imaging (MRI) was obtained to evaluate cartilage and ligament integrity. Clinical outcomes at the time of MRI were assessed using the Foot Function Index (FFI) and the American Orthopaedic Foot & Ankle Society (AOFAS) score. Demographic variables, including type of osteotomy and outcome measures, were compared between patients with and without facet penetration. RESULTS:Thirty-one patients met inclusion criteria. Subtalar facet penetration was detected in 11 patients (35%) on postoperative CT. No significant differences were observed between groups with respect to demographic variables. MRI analysis revealed no relevant differences in cartilage degeneration. FFI and AOFAS scores were comparable between groups. CONCLUSION:Subtalar facet penetration occurred in one-third of patients after LLOT (Evans and Hintermann). With the numbers available, no significant differences in clinical or radiographic outcomes were detected at a minimum 5-year follow-up, suggesting that minor facet violations may have limited clinical relevance. LEVEL OF EVIDENCE:Level III, retrospective cohort study.

Background: Patients treated with an Ilizarov external fixator often feature risk factors that impair wound healing such as diabetes, peripheral arterial disease, obesity, and renal insufficiency. A 2-staged approach, with initial bony correction (Kirschner wire or hybrid) followed by delayed Ilizarov application by 5 days, is intended to support wound healing by allowing for reduction of soft tissue swelling and enhancing postoperative wound care. We hypothesized that this method is associated with fewer wound complications but increased use of resources.Methods: A retrospective review of 98 cases treated with an Ilizarov fixator (2004-2024) was conducted. Surgical management included 2-stage (n = 53, 54%) and single-stage (n = 45, 46%) procedures. Baseline characteristics and risk factors for compromised wound healing were recorded. Patients were stratified into 3 subgroups to enable comparative analysis: infection-related reconstructions (IRR), Charcot arthropathy (CA) and other applications. Preoperative presence of infection and ulceration was recorded. Primary endpoints were rates of impaired wound healing and wound revisions within 3 months post removal. Secondary endpoints were hospital length of stay after bony fixation, and total hospitalization costs.Results: Wound revision rates were significantly lower in the 2-stage group (9% vs 36%; OR 5.3, 95% CI 1.8-17.9; P = .0025) particularly in the CA subgroup (0% vs 38%; P = .010) or when an infection was present (14% vs 44%; OR 4.6, 95% CI 1.2-22.3, P = .0138). Impaired wound healing was significantly lower in patients with a 2-stage procedure (30% vs 55%; OR 2.9, 95% CI 1.3-6.6, P = .021). As an exploratory secondary outcome, no statistically significant difference in length of hospital stay or total hospitalization costs was observed.Conclusion: Two-stage Ilizarov ring fixator application in high-risk foot and ankle surgery was associated with lower rates of impaired wound healing and wound revisions, particularly in CA and infection cases, without increasing hospital stay or costs.

Background/Objectives: In orthopedic (diabetic) foot surgery, the serum C-reactive protein (CRP) level is frequently measured not only as a diagnostic tool, but also as a control inflammatory marker in the follow-up of postoperative surgical-site infections (SSIs) Methods: We investigated the predictive value of the post-debridement routine (control) serum CRP level in adult (diabetic) patients with an SSI in the foot. We excluded community-acquired (diabetic foot) infections and focused on the predictive accuracy of routine (control) CRP measurements in terms of ultimate therapeutic failures. Results: The median pre- and postoperative CRP levels were 25 mg/L and 8.8 mg/L, respectively. In group comparisons and multivariate assessment, neither the immediate (relative and absolute) drop in the serum CRP level, nor its values between 5 and 8 weeks and between 11 and 14 weeks predicted the failure risk of 19%. In contrast, in cases of surprisingly elevated CRP levels, this finding leads to unnecessary radiological (median costs approximatively USD 200), clinical, microbiological urinary sample (median costs USD 50), and laboratory (one CRP sample USD 10) exams. These additional exams also likely prolong the duration of hospitalization by one to two days (e.g., whilst awaiting the microbiological results) and often generate unnecessary consultations among internist and/or infectious diseases experts (USD 50). Conclusions: Routine, postoperative CRP monitoring during the treatment of established orthopedic (diabetic) foot SSIs is unnecessarily costly, and should be avoided in favor of clinical surveillance of the postoperative evolution.

ABSTRACT:Focal nerve injuries are often associated with neuropathic pain. Preclinical research suggests altered neuroimmune signalling underlies such neuropathic pain; however, its cause remains poorly understood in humans. In this multicentre cohort study, we describe the local cellular and molecular signature of neuropathic pain at the lesion site, using Morton's neuroma as a human model system of neuropathic pain (n = 22; 18 women) compared with nerves from participants without nerve injury (n = 11; 4 women). Immunofluorescent staining revealed demyelination and chronic infiltration of immune cells in Morton's neuroma. RNA bulk sequencing identified 3349 differentially expressed genes between Morton's neuroma and controls. Gene ontology enrichment analysis and weighted gene co-expression network analyses revealed modules specific for host defence and neurogenesis. Deconvolution analysis confirmed higher densities of macrophages and B cells in Morton's neuroma than control samples. Modules associated with defence response, neurogenesis, and muscle system development as well as macrophage cell populations identified by deconvolution correlated with patients' paroxysmal or evoked pain. Of note, we identified a consistently differentially expressed gene signature ( MARCO, CD163, STAB1 ) , indicating the presence of a specific M(GC) subset of macrophages. MARCO gene expression correlated with paroxysmal pain. Targeted immunofluorescent analyses confirmed higher densities of intraneural CD163 + MARCO + macrophage subsets in Morton's neuroma. Our findings provide detailed insight into the local molecular signature in the context of human focal nerve injury. There is clear evidence for an ongoing role of the immune system in chronic peripheral neuropathic pain in humans, with macrophages and specifically the M(GC) MARCO + subset implicated.

BACKGROUND:Ultrasound-based bone surface segmentation is crucial in computer-assisted orthopedic surgery. However, ultrasound images have limitations, including a low signal-to-noise ratio, acoustic shadowing, and speckle noise, which make interpretation difficult. Existing deep learning models for bone segmentation rely primarily on costly manual labeling by experts, limiting dataset size and model generalizability. Additionally, the complexity of ultrasound physics and acoustic shadow makes the images difficult for humans to interpret, leading to incomplete labels in low-intensity and anechoic regions and limiting model performance. To advance the state-of-the-art in ultrasound bone segmentation and establish effective model benchmarks, larger and higher-quality datasets are needed. METHODS:We propose a methodology for collecting ex-vivo ultrasound datasets with automatically generated bone labels, including anechoic regions. The proposed labels are derived by accurately superimposing tracked bone Computed Tomography (CT) models onto the tracked ultrasound images. These initial labels are refined to account for ultrasound physics. To clinically evaluate the proposed method, an expert physician from our university hospital specialized in orthopedic sonography assessed the quality of the generated bone labels. A neural network for bone segmentation is trained on the collected dataset and its predictions are compared to expert manual labels, evaluating accuracy, completeness, and F1-score. RESULTS:We collected UltraBones100k, the largest known dataset comprising 100k ex-vivo ultrasound images of human lower limbs with bone annotations, specifically targeting the fibula, tibia, and foot bones. A Wilcoxon signed-rank test with Bonferroni correction confirmed that the bone alignment after our optimization pipeline significantly improved the quality of bone labeling (p<0.001). The model trained on UltraBones100k consistently outperforms manual labeling in all metrics, particularly in low-intensity regions (at a distance threshold of 0.5 mm: 320% improvement in completeness, 27.4% improvement in accuracy, and 197% improvement in F1 score) CONCLUSION:: This work is promising to facilitate research and clinical translation of ultrasound imaging in computer-assisted interventions, particularly for applications such as 2D bone segmentation, 3D bone surface reconstruction, and multi-modality bone registration.

Background: Subtle chronic or latent instabilities are difficult to delineate with currently available diagnostic modalities and do not allow assessment of ligamentous functionality. The noninvasive bilateral external torque computed tomography (CT) was able to reliably detect syndesmotic lesions in a cadaveric study. The aim of the study was to test the external torque device in young, healthy subjects at 3 different torque levels and to demonstrate comparability with the contralateral side. Methods: Ten healthy subjects without history of injury or surgery to the ankle joint were enrolled in this cross-sectional study. Four CT scans were performed. During the scans, the lower legs and feet were placed in an external torque device with predefined external rotation torques of 0, 2.5, 5, and 7.5 Nm. Five different radiographic measures of syndesmotic stability were measured: anterior distance (AD), tibiofibular clear space (TCS), posterior distance (PD), external rotation (ER), and β angle. Results: With increasing external torque, slight increases in AD, ER, and β angle were observed, whereas TCS and PD decreased slightly. Large absolute differences were found between the healthy subjects for all measured parameters, regardless of the external torque applied. Differences from the contralateral side using the same external torque were minimal for all parameters, but smallest for AD with a maximum difference of 0.5 mm. Conclusion: Using the healthy contralateral ankle joint is appropriate for assessing syndesmotic stability based on minimal intraindividual side differences using the external torque device. Side differences >0.5 mm in AD and >0.9 mm in PD may be considered abnormal and may indicate significant instability of the syndesmosis. However, future studies are needed to define definitive cutoff values for relevant side differences in acute and chronic syndesmotic instability to guide clinicians in their treatment decisions.

Background: Acquired adult flatfoot deformity (AAFD) results in a loss of the medial longitudinal arch of the foot and dysfunction of the posteromedial soft tissues. Hintermann osteotomy (H-O) is often used to treat stage II AAFD. The procedure is challenging because of variations in the subtalar facets and limited intraoperative visibility. We aimed to assess the impact of augmented reality (AR) guidance on surgical accuracy and the facet violation rate. Methods: Sixty AR-guided and 60 conventional osteotomies were performed on foot bone models. For AR osteotomies, the ideal osteotomy plane was uploaded to a Microsoft HoloLens 1 headset and carried out in strict accordance with the superimposed holographic plane. The conventional osteotomies were performed relying solely on the anatomy of the calcaneal lateral column. The rate and severity of facet joint violation was measured, as well as accuracy of entry and exit points. The results were compared across AR-guided and conventional osteotomies, and between experienced and inexperienced surgeons. Results: Experienced surgeons showed significantly greater accuracy for the osteotomy entry point using AR, with the mean deviation of 1.6 ± 0.9 mm (95% CI 1.26, 1.93) compared to 2.3 ± 1.3 mm (95% CI 1.87, 2.79) in the conventional method ( P = .035). The inexperienced had improved accuracy, although not statistically significant ( P = .064), with the mean deviation of 2.0 ± 1.5 mm (95% CI 1.47, 2.55) using AR compared with 2.7 ± 1.6 mm (95% CI 2.18, 3.32) in the conventional method. AR helped the experienced surgeons avoid full violation of the posterior facet ( P = .011). Inexperienced surgeons had a higher rate of middle and posterior facet injury with both methods ( P = .005 and .021). Conclusion: Application of AR guidance during H-O was associated with improved accuracy for experienced surgeons, demonstrated by a better accuracy of the osteotomy entry point. More crucially, AR guidance prevented full violation of the posterior facet in the experienced group. Further research is needed to address limitations and test this technology on cadaver feet. Ultimately, the use of AR in surgery has the potential to improve patient and surgeon safety while minimizing radiation exposure. Clinical Relevance: Subtalar facet injury during lateral column lengthening osteotomy represents a real problem in clinical orthopaedic practice. Because of limited intraoperative visibility and variable anatomy, it is hard to resolve this issue with conventional means. This study suggests the potential of augmented reality to improve the osteotomy accuracy.

Despite growing numbers of scientific publications on the optimal antibiotic treatment for diabetic foot infections, the data on the adult population with non-diabetic (postsurgical) foot infections is limited. Therefore, one of the largest single-center databases at the Balgrist University Hospital in Zurich, Switzerland, was established between January 2014 and August 2022. Using a case–control study design, we retrospectively investigated failures of combined surgical and antibiotic therapy for surgical site foot infections (SSIs). Overall, 17.4% of the episodes experienced therapeutic failures, particularly in patients with infected ankle prostheses. However, age, biological sex, pathogens, the duration of post-debridement antibiotic treatment, the number of surgical debridements, or the use of negative-pressure wound care altered the failure risk. In the multivariate logistic regression analyses, the duration of postsurgical antibiotic use was completely indifferent (as a continuous variable with an odds ratio of 1.0 and a 95% confidence interval ranging from 0.96 to 1.03) when stratified into inter-tertiary groups. Our findings suggest that shorter courses of systemic antibiotics may be appropriate in non-diabetic adults, supporting better antibiotic stewardship. Ongoing randomized controlled trials are under way to investigate which patients might safely receive shorter antibiotic treatments for surgical site infections following elective foot and ankle procedures.

Background:This study aimed to evaluate the long-term results of hallux valgus correction with a distal metatarsal reversed-L (ReveL) osteotomy. Methods:Eighty-eight patients (131 feet) were evaluated after a mean follow-up of 14.2 years (range, 10 to 18 years). Weight-bearing foot radiographs were analyzed preoperatively, at 6 weeks postoperatively, and at the final follow-up for the following parameters: hallux valgus angle (HVA), intermetatarsal angle (IMA), first metatarsophalangeal joint (MTPJ) congruence angle, sesamoid position, presence of the round sign, and first MTPJ arthritis. The visual analog scale (VAS) and the Foot and Ankle Outcome Score (FAOS) assessed postoperative pain and function. Univariate and multivariable logistic regression analyses identified risk factors for hallux valgus recurrence and an inferior clinical outcome. Results:All radiographic parameters significantly improved at the 6-week follow-up and the final follow-up (p < 0.001). The recurrence rate (HVA >20°) was 14%. A preoperative HVA of >28° (odds ratio [OR], 9.1; p = 0.02) and a 6-week postoperative HVA of >15° (OR, 4.6; p = 0.03) were independent risk factors for recurrence. At the final follow-up, all FAOS subscales resembled high postoperative function (median, 100 points [range of the interquartile range (IQR), 81 to 100 points]). A preoperative body mass index of >30 kg/m2 was associated with lower FAOS quality of life (QOL) (p = 0.04), and postoperative hallux varus was associated with lower FAOS activities of daily living (p = 0.048). Patients with first MTPJ arthritis of grade 2 or higher at the final follow-up had significantly lower FAOS subscales (p < 0.01) except for QOL. Hallux valgus recurrence did not influence the long-term outcome. A symptomatic implant was the main cause of revision (15%). In 94% of cases, the patients were satisfied with the hallux appearance and, in 92% of cases, the patients were satisfied with postoperative pain reduction. Conclusions:Hallux valgus correction with a ReveL osteotomy led to high long-term satisfaction rates. A preoperative HVA of >28° and a 6-week postoperative HVA of >15° increased the risk of hallux valgus recurrence. First MTPJ arthritis was the leading cause of inferior clinical results, whereas radiographic hallux valgus recurrence had no impact on the clinical results. First MTPJ arthritis at the final follow-up was associated with an inferior clinical outcome, whereas radiographic hallux valgus recurrence had no impact on the long-term clinical results. Level of Evidence:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Category: Ankle; Sports Introduction/Purpose: 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.

Augmented reality is a promising technology with potential benefit in simplifying visualization and increased accuracy in orthopedic surgery. In hallux valgus surgery, an in vitro study suggests that augmented reality especially helps unexperienced surgeons to perform the osteotomy correctly. However, in clinical practice, augmented reality has not yet found entry in hallux valgus surgery. The future will show if the rapidly developing technology will overcome technical obstacles to make it beneficial to (unexperienced) surgeons.

Peripheral neuropathic pain remains challenging to treat, partly due to our limited understanding of the molecular mechanisms at play in humans. In this multicentre cohort study, we describe the local molecular signature of neuropathic pain at the lesion site, using peripheral nerves of patients with Morton’s neuroma as a human model system of neuropathic pain. Plantar tibial nerves were collected from 22 patients with Morton’s neuroma (18 female, median age 60.0 [IQR 16.0] years) and control nerves from 11 participants (4 females, 58.0 [21.0] years) without a nerve injury. Pre-surgery, we collected data on pain severity, duration and nature (e.g., neuropathic pain inventory, NPSI). RNA bulk sequencing of peripheral nerves identified 3349 genes to be differentially expressed between Morton’s neuroma and controls. Gene ontology enrichment analysis and weighted gene co-expression network analyses (WGCNA) revealed modules specific for host defence and neurogenesis. Deconvolution analysis confirmed that the densities of macrophages as well as B-cells were higher in Morton’s neuroma than control samples. The findings for T-cells were inconclusive. Modules associated with defence response, neurogenesis and muscle system development correlated with paroxysmal and evoked pain in people with Morton’s neuroma. Macrophage cell populations identified by deconvolution analysis as well as single differentially expressed genes ( MARCO, CD163, STAB1; indicating the presence of a specific M(GC) subset of macrophages) correlated with paroxysmal pain. Immunofluorescent analyses confirmed the presence of demyelination, higher densities of intraneural T-cells and CD163+MARCO+ macrophage subsets in Morton’s neuroma compared to control nerves. Histological CD68+ macrophage density correlated with burning pain. Our findings provide detailed insight into the local molecular signature in the context of human focal nerve injury. There is clear evidence for an ongoing role of the immune system in chronic peripheral neuropathic pain in humans, with macrophages and specifically the M(GC) MARCO+ subset implicated. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement ABS is supported by a Wellcome Trust Clinical Career Development Fellowship (222101/Z/20/Z). IDS and PSS were funded by the Clinical Research Priority Program (CRPP) Pain from the University of Zurich, Switzerland. PSS is supported by postdoctoral fellowships from the International Foundation for Research in Paraplegia (P198F), the Swiss National Science Foundation (P500PB_214416), and Michael Smith Health Research BC (RT-2023-3173). This research was funded in whole, or in part, by the Wellcome Trust [222101/Z/20/Z]. For the purpose of Open Access, the author has applied a CC BY public copyright license to any Author Accepted Manuscript version arising from this submission. We also received funding from from ONO pharamceuticals Ltd. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics Committee South Central - Oxford C Research Ethics Committee gave ethical approval for this research (REF 18/SC/0410). Ethics Committee London - Camden & Kings Cross Research Ethics Committee gave ethical approval for this research (REC16/LO/1920) Ethics committee of Canton of Zurich gave ethical approval for this work (2018-02198). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes

BACKGROUND:If tibiofibular syndesmotic injury is undetected, chronic instability may lead to persistent pain and osteoarthritis. So far, no reliable diagnostic method has been available. The primary objectives of this study were to determine whether defined lesions of the syndesmosis can be correlated with specific tibiofibular joint displacements caused by external rotational torque and to compare the performance of bilateral external torque computed tomography (BET-CT) and arthroscopy. Secondary objectives included an evaluation of the reliability of CT measurements and the suitability of the healthy contralateral ankle as a reference. METHODS:Seven pairs of healthy, cadaveric lower legs were tested and assigned to 2 groups: (1) supination-external rotation (SER) and (2) pronation-external rotation (PER). In the intact state and after each surgical step, an ankle arthroscopy and 3 CT scans were performed. During the scans, the specimens were placed in an external torque device with 2.5, 5.0, and 7.5 Nm of torque applied. RESULTS:The arthroscopic and CT parameters showed significant correlations in all pairwise comparisons. The receiver operating characteristic (ROC) curve analyses yielded the best prediction of syndesmotic instability with the anterior tibiofibular distance on CT, with a sensitivity of 84.1% and a specificity of 95.2% (area under the curve [AUC], 94.8%; 95% confidence interval [CI], 0.916 to 0.979; p < 0.0001) and with the middle tibiofibular distance on arthroscopy, with a sensitivity of 76.2% and specificity of 92.3% (AUC, 91.2%; 95% CI, 0.837 to 0.987; p < 0.0001). Higher torque amounts increased the rate of true-positive results. CONCLUSIONS:BET-CT reliably detects experimental syndesmotic rotational instability, compared with the healthy side, with greater sensitivity and similar specificity compared with the arthroscopic lateral hook test. Translation of these experimental findings to clinical practice remains to be established. LEVEL OF EVIDENCE:Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

To assess calf muscle constitution in chronic Achilles tendon disease (ATD) using two-point Dixon-based MRI (2pt-MRIDIXON). This retrospective study analyzed 91 patients (36 females; 57.0 ± 14.4 years) with midportion or insertional chronic ATD who underwent clinical MRI of the Achilles tendon (AT), including 2pt-MRIDIXON for quantitative assessment of calf muscle fat content (MFC). Additionally, two radiologists qualitatively assessed MFC, AT quality, and co-pathologies. 2pt-MRIDIXON-derived fat fractions (FF) were related to patients’ demographics and qualitative imaging findings. The overall mean FF derived from 2pt-MRIDIXON of the triceps surae muscle was 11.2 ± 9.3

Surgical site infection (SSI) after elective orthopedic foot and ankle surgery is uncommon and may be higher in selected patient groups. Our main aim was to investigate the risk factors for SSI in elective orthopedic foot surgery and the microbiological results of SSI in diabetic and non-diabetic patients, in a tertiary foot center between 2014 and 2022. Overall, 6138 elective surgeries were performed with an SSI risk of 1.88%. The main independent associations with SSI in a multivariate logistic regression analysis were an ASA score of 3–4 points, odds ratio (OR) 1.87 (95% confidence interval (CI) 1.20–2.90), internal, OR 2.33 (95% CI 1.56–3.49), and external material, OR 3.08 (95% CI 1.56–6.07), and more than two previous surgeries, OR 2.86 (95% CI 1.93–4.22). Diabetes mellitus showed an increased risk in the univariate analysis, OR 3.94 (95% CI 2.59–5.99), and in the group comparisons (three-fold risk). In the subgroup of diabetic foot patients, a pre-existing diabetic foot ulcer increased the risk for SSI, OR 2.99 (95% CI 1.21–7.41), compared to non-ulcered diabetic patients. In general, gram-positive cocci were the predominant pathogens in SSI. In contrast, polymicrobial infections with gram-negative bacilli were more common in contaminated foot surgeries. In the latter group, the perioperative antibiotic prophylaxis by second-generation cephalosporins did not cover 31% of future SSI pathogens. Additionally, selected groups of patients revealed differences in the microbiology of the SSI. Prospective studies are required to determine the importance of these findings for optimal perioperative antibiotic prophylactic measures.

BACKGROUND:In progressive collapsing foot deformity (PCFD), an internal and plantar rotation of the talus relative to the calcaneus may result in painful peritalar subluxation. Medial soft tissue procedures (eg, spring ligament repair) aim to correct the talar position via the navicular bone if bony correction alone is not sufficient. The effect of the medial soft tissue reconstruction on the talar reposition remains unclear. We hypothesized that a subtalar talocalcaneal ligament reconstruction might be favorable in PCFD to correct talar internal malposition directly. This pilot study aims to evaluate the anatomical feasibility and kinematic behavior of a subtalar ligament reconstruction in PCFD. METHODS:Three-dimensional surface model from 10 healthy ankles were produced. A total of 1089 different potential ligament courses were evaluated in a standardized manner. A motion of inversion/eversion and talar internal/external in relation to the calcaneus were simulated and the ligament strain, expressed as a positive length variation, for each ligament was analyzed. The optimal combination for the ligament reconstruction with increased length in internal rotation of the talus, isometric kinematic behavior in inversion/eversion, and extraarticular insertion on talus and calcaneus was selected. RESULTS:A laterodistal orientation of the talar insertion point in respect to the subtalar joint axis and laterodistal deviation of the calcaneal insertion point presents the highest ligament lengthening in internal talar rotation (+0.56 mm [3.8% of total length]) and presented a near-isometric performance in inversion/eversion (+0.01 to -0.01 mm [0.1% of total length]). CONCLUSION:This kinematic model shows that a ligament reconstruction in the subtalar space presents a pattern of length variation that may stabilize the internal talar rotation without impeding the physiological subtalar motion. CLINICAL RELEVANCE:This study investigates the optimal location, feasibility, and kinematic behavior of a ligament reconstruction that could help stabilize peritalar subluxation in progressive collapsing foot deformity. [Formula: see text].

Background: Painful degenerative joint disease (DJD) of the first metatarsophalangeal joint (MTP I), or hallux rigidus, mainly occurs in later stages of life. For end-stage hallux rigidus, MTP I arthrodesis is considered the gold standard. As young and active patients are affected considerably less frequently, it currently remains unclear, whether they benefit to the same extent. We hypothesized that MTP I arthrodesis in younger patients would lead to an inferior outcome with decreased rates of overall with lower rates of patient postoperative pain and function compared to an older cohort.Methods: All patients aged <50 y ears who underwent MTP I arthrodesis at our institution between 1995 and 2012 were included in this study. This group was then matched and compared with a group of patients aged >60 years. Minimum follow-up was 10 years. Outcome measures were Tegner activity score (TAS), a "Virtual Tegner activity score" (VTAS), the visual analog scale (VAS), and the Foot Function index (FFI).Results: Sixty-one MTP I fusions (n = 28 young, n = 33 old) in 46 patients were included in our study at an average of 14 years after surgery. Younger patients experienced significantly more pain relief as reflected by changes in VAS and FFI Pain subscale scores. No difference in functional outcomes was found with change in the FFI function subscale or in the ability to have desired functional outcomes using the ratio of TAS to VTAS. Revision rate did not differ between the two groups apart from hardware removal, which was significantly more likely in the younger group.Conclusion: In patients below the age of 50 years with end-stage DJD of the first metatarsal joint, MTP I arthrodesis not only yielded highly satisfactory postoperative results at least equal outcome compared to an older cohort of patients aged >60 years at an average 14 years' follow-up. Based on these findings, we consider first metatarsal joint fusion even for young patients is a valid option to treat end-stage hallux rigidus.Level of Evidence: Level III, a case-control study.