Understanding Radiographic Measurements Used in Foot and Ankle Surgery

Morphological changes in flatfoot: a 3D analysis using weight-bearing CT scans

BACKGROUND

Flatfoot is a condition resulting from complex three-dimensional (3D) morphological changes. Most Previous studies have been constrained by using two-dimensional radiographs and non-weight-bearing conditions. The deformity in flatfoot is associated with the 3D morphology of the bone. These morphological changes affect the force line conduction of the hindfoot/midfoot/forefoot, leading to further morphological alterations. Given that a two-dimensional plane axis overlooks the 3D structural information, it is essential to measure the 3D model of the entire foot in conjunction with the definition under the standing position. This study aims to analyze the morphological changes in flatfoot using 3D measurements from weight-bearing CT (WBCT).

METHOD

In this retrospective comparative our CT database was searched between 4-2021 and 3-2022. Following inclusion criteria were used: Patients were required to exhibit clinical symptoms suggestive of flatfoot, including painful swelling of the medial plantar area or abnormal gait, corroborated by clinical examination and confirmatory radiological findings on CT or MRI. Healthy participants were required to be free of any foot diseases or conditions affecting lower limb movement. After applying the exclusion criteria (Flatfoot with other foot diseases), CT scans (mean age = 20.9375, SD = 16.1) confirmed eligible for further analysis. The distance, angle in sagittal/transverse/coronal planes, and volume of the two groups were compared on reconstructed 3D models using the t-test. Logistic regression was used to identify flatfoot risk factors, which were then analyzed using receiver operating characteristic curves and nomogram.

RESULT

The flatfoot group exhibited significantly lower values for calcaneofibular distance (p = 0.001), sagittal and transverse calcaneal inclination angle (p < 0.001), medial column height (p < 0.001), sagittal talonavicular coverage angle (p < 0.001), and sagittal (p < 0.001) and transverse (p = 0.015) Hibb angle. In contrast, the sagittal lateral talocalcaneal angle (p = 0.013), sagittal (p < 0.001) and transverse (p = 0.004) talocalcaneal angle, transverse talonavicular coverage angle (p < 0.001), coronal Hibb angle (p < 0.001), and sagittal (p < 0.001) and transverse (p = 0.001) Meary's angle were significantly higher in the flatfoot group. The sagittal Hibb angle (B =  - 0.379, OR = 0.684) and medial column height (B =  - 0.990, OR = 0.372) were identified as significant risk factors for acquiring a flatfoot.

CONCLUSION

The findings validate the 3D spatial position alterations in flatfoot. These include the abduction of the forefoot and prolapse of the first metatarsal proximal, the arch collapsed, subluxation of the talonavicular joint in the midfoot, adduction and valgus of the calcaneus, adduction and plantar ward movement of the talus in the hindfoot, along with the first metatarsal's abduction and dorsiflexion in the forefoot.

Effectiveness of synthetic versus autologous bone grafts in foot and ankle surgery: a systematic review and meta-analysis

BACKGROUND

All orthopaedic procedures, comprising foot and ankle surgeries, seemed to show a positive trend, recently. Bone grafts are commonly employed to fix bone abnormalities resulting from trauma, disease, or other medical conditions. This study specifically focuses on reviewing the safety and efficacy of various bone substitutes used exclusively in foot and ankle surgeries, comparing them to autologous bone grafts.

METHODS

The systematic search involved scanning electronic databases including PubMed, Scopus, Cochrane online library, and Web of Science, employing terms like 'Bone substitute,' 'synthetic bone graft,' 'Autograft,' and 'Ankle joint.' Inclusion criteria encompassed RCTs, case-control studies, and prospective/retrospective cohorts exploring different bone substitutes in foot and ankle surgeries. Meta-analysis was performed using R software, integrating odds ratios and 95% confidence intervals (CI). Cochrane's Q test assessed heterogeneity.

RESULTS

This systematic review analyzed 8 articles involving a total of 894 patients. Out of these, 497 patients received synthetic bone grafts, while 397 patients received autologous bone grafts. Arthrodesis surgery was performed in five studies, and three studies used open reduction techniques. Among the synthetic bone grafts, three studies utilized a combination of recombinant human platelet-derived growth factor BB homodimer (rhPDGF-BB) and beta-tricalcium phosphate (β-TCP) collagen, while four studies used hydroxyapatite compounds. One study did not provide details in this regard. The meta-analysis revealed similar findings in the occurrence of complications, as well as in both radiological and clinical evaluations, when contrasting autografts with synthetic bone grafts.

CONCLUSION

Synthetic bone grafts show promise in achieving comparable outcomes in radiological, clinical, and quality-of-life aspects with fewer complications. However, additional research is necessary to identify the best scenarios for their use and to thoroughly confirm their effectiveness.

LEVELS OF EVIDENCE

Level II.

Comparison of Minimally Invasive Chevron Akin and Open Lapidus Surgery in Older Patients at a Minimum 1-Year Follow-Up

Background

Hallux valgus deformity affects more than 35% of people aged ≥65 years. Surgical correction in this population can be more complicated because of poor bone quality, worse deformity, and postoperative recovery challenges. The purpose of this study was to compare the radiographic and clinical outcomes of patients aged ≥65 years who underwent either open Lapidus or minimally invasive chevron Akin osteotomy for bunion correction.

Methods

A retrospective review identified 62 patients aged ≥65 years who were treated surgically for hallux valgus with at least 1-year postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores (physical function and pain interference). Preoperative and at least 6-month postoperative radiographs were measured for the hallux valgus angle and intermetatarsal angle. PROMIS scores were obtained preoperatively and at 1 and/or 2 years postoperatively. Differences in demographic, clinical, and radiographic outcomes were assessed using the Mann Whitney U test and P values were adjusted for a false discovery rate of 5%.

Results

There was no difference between the MIS and open cohorts in pre- or postoperative radiographic measurements or clinical outcomes at any time point. At 1 year postoperatively, both groups had statistically significant improvements in the PROMIS pain interference domain but only the MIS group had a statistically significant improvement in the PROMIS physical function domain. Clinical significance was equivocal. At 2 years postoperatively, there were clinically and statistically significant improvements in the PROMIS pain interference and physical function domains for the open and MIS groups.

Conclusion

Patients in both surgical groups had improvement in radiographic measurements and 2-year PROMIS scores, although there was no clinical or statistical difference found between groups. MIS and open surgical techniques appear to be safe and effective in correcting hallux valgus in older patients; however, patients may need to be counseled that maximum improvement after surgery may take more than 1 year.

Level of Evidence

Level III, retrospective cohort study.

Hazard of Failed Nonoperative Management for Symptomatic Accessory Navicular in Children and Adolescents: A Population-Based Case-Cohort Study

BACKGROUND

The accessory navicular (AN) is an idiopathic condition of the foot present in 4% to 21% of the population. Most ANs remain asymptomatic, but children and adolescents who develop symptoms can have remarkably reduced quality of life. Although many respond to conservative measures, surgery is occasionally needed. Our purpose was to determine factors associated with the failure of nonoperative management.

METHODS

This single-institution retrospective case-cohort study included patients up to age 19 years presenting between 2000 and 2021 with symptomatic AN and treated with standard-of-care. All 298 surgical cases, indicating failed nonoperative treatment, were included. For the subcohort, 299 patients were randomly sampled from all eligible patients, regardless of treatment. Baseline characteristics were summarized for the surgical cases and subcohort. Proportional hazards assumptions were checked and stratification implemented when necessary. Marginal structural proportional hazard modeling was used to estimate hazard ratios with 95% confidence intervals via inverse probability and LinYing weighting methods.

RESULTS

The 298 surgical cases failed nonoperative management at a median of 5.2 months (IQR, 2.0-11.6 mo). In the subcohort, 86 failures of nonoperative management and 213 nonfailures constituted a 28.8% surgery rate. In both cohorts, nearly all patients played sports. Univariate proportional hazard modeling found older age (P=0.02) and activity limitation (P<0.001) at presentation, female sex (P=0.002), higher BMI (P=0.01), AN on the right (P<0.001), and bone marrow edema of the AN (P<0.001) and navicular body (P<0.001) on MRI were associated with increased hazard of nonoperative failure. Nearly all of the surgical cohort reported improvement in pain (278/296, 94%) and returned to their primary sport (236/253, 93%) after surgery. Most also experienced full resolution of symptoms (187/281, 67%).

CONCLUSIONS

Symptomatic AN predominantly affects female athletes, leading to surgery in 28.8% of our subcohort. Conservative treatment may be less successful-and therefore surgery could be more strongly considered-in older age, activity limitation at presentation, female sex, higher BMI, right-sided AN, and bone marrow edema on MRI. Surgery is effective for symptomatic and functional improvement.

LEVEL OF EVIDENCE

Case-cohort-Level III.

Development and validation of a fully automated tool to quantify 3D foot and ankle alignment using weight-bearing CT

INTRODUCTION

Foot and ankle alignment plays a pivotal role in human gait and posture. Traditional assessment methods, relying on 2D standing radiographs, present limitations in capturing the dynamic 3D nature of foot alignment during weight-bearing and are prone to observer error. This study aims to integrate weight-bearing CT (WBCT) imaging and advanced deep learning (DL) techniques to automate and enhance quantification of the 3D foot and ankle alignment.

METHODS

Thirty-two patients who underwent a WBCT of the foot and ankle were retrospectively included. After training and validation of a 3D nnU-Net model on 45 cases to automate the segmentation into bony models, 35 clinically relevant 3D measurements were automatically computed using a custom-made tool. Automated measurements were assessed for accuracy against manual measurements, while the latter were analyzed for inter-observer reliability.

RESULTS

DL-segmentation results showed a mean dice coefficient of 0.95 and mean Hausdorff distance of 1.41 mm. A good to excellent reliability and mean prediction error of under 2 degrees was found for all angles except the talonavicular coverage angle and distal metatarsal articular angle.

CONCLUSION

In summary, this study introduces a fully automated framework for quantifying foot and ankle alignment, showcasing reliability comparable to current clinical practice measurements. This operator-friendly and time-efficient tool holds promise for implementation in clinical settings, benefiting both radiologists and surgeons. Future studies are encouraged to assess the tool's impact on streamlining image assessment workflows in a clinical environment.

Impact of Subtalar Distraction Arthrodesis on Ankle Joint: Radiological Insights from Modified Grice-Green Procedure

Subtalar distraction arthrodesis (SDA) is a surgical procedure designed to treat hindfoot deformities associated with isolated subtalar joint arthritis. In 1996, Fitzgibbons was the first to observe that, in some cases, hindfoot fusion appeared to be associated with the development of tibiotalar valgus tilt. Since then, few studies have addressed this issue. Given that hindfoot fusion can be performed using various techniques, this study investigated the potential tibiotalar joint frontal or sagittal modifications resulting from the modified Grice-Green technique. All the consecutive patients who underwent the modified Grice-Green procedure were included. The patient records were reviewed to extract demographic data. Weight-bearing foot and ankle radiographs were assessed to measure the talar tilt angle and the tibiotalar ratio on the same picture archiving and communication system by three independent observers. A total of 69 patients met the criteria for inclusion. The mean talar tilt showed no substantial changes, since the increase from 1.46 ± 1.62 preoperatively to 1.93 ± 2.19 at a minimum of 8 months postoperatively was not statistically significant (p = 0.47). The average preoperative tibiotalar ratio significantly increased from 33.4 ± 4.4% to 35 ± 4% postoperatively (p = 0.007), although remaining within the normal range, indicating a possible realignment of the posterior facet of the subtalar joint. In conclusion, this study highlights the effectiveness of the modified Grice-Green procedure in achieving a favorable realignment without impacting the ankle joint, particularly regarding tibiotalar valgus tilt.

Dynamic Gait Analysis in Paediatric Flatfeet: Unveiling Biomechanical Insights for Diagnosis and Treatment

BACKGROUND

Flatfeet in children are common, causing concern for parents due to potential symptoms. Technological advances, like 3D foot kinematic analysis, have revolutionized assessment. This review examined 3D assessments in paediatric idiopathic flexible flat feet (FFF).

METHODS

Searches focused on paediatric idiopathic FFF in PubMed, Web of Science, and SCOPUS. Inclusion criteria required 3D kinematic and/or kinetic analysis during posture or locomotion, excluding non-idiopathic cases, adult feet, and studies solely on pedobarography or radiographs.

RESULTS

Twenty-four studies met the criteria. Kinematic and kinetic differences between FFF and typical feet during gait were outlined, with frontal plane deviations like hindfoot eversion and forefoot supination, alongside decreased second peak vertical GRF. Dynamic foot classification surpassed static assessments, revealing varied movement patterns within FFF. Associations between gait characteristics and clinical measures like pain symptoms and quality of life were explored. Interventions varied, with orthoses reducing ankle eversion and knee and hip abductor moments during gait, while arthroereisis normalized calcaneal alignment and hindfoot eversion.

CONCLUSIONS

This review synthesises research on 3D kinematics and kinetics in paediatric idiopathic FFF, offering insights for intervention strategies and further research.

Stable Clinical and Radiological Outcomes at Medium and over 5 Year Follow Up of Calcaneus Fracture Open Reduction Internal Fixation Using a Sinus Tarsi Approach

The sinus tarsi approach is increasingly growing in popularity for open reduction internal fixation of calcaneus fractures. Multiple studies have demonstrated favorable short-term results compared to the traditional extensile L incision, however long-term data over 5 years is currently limited to a single retrospective case series. Following local ethical approval, all patients who had completed a minimum 5 years from time of operation were contacted with a Standardized Telephone Questionnaire completed. This followed a previous retrospective chart review, with follow up telephone or clinic consultation performed by Davey et al. of this cohort at mean 35 months. Thirty-four fractures (31 patients) completed minimum 5 year follow up from the eligible group of 54 fractures (49 patients). Regarding functional outcomes, a significant improvement in mean Maryland Foot Score was observed between short- (mean 35.8 months) and medium-term (mean 81.9 months) of 77.6 (SD 15.0) to 86 (SD 7.9) (p = .0082). There was no significant difference in postoperative and long term radiographic Bohler's angle (p = .9683). Eleven feet (32%) proceeded to require reoperation, with removal of metal performed in 10 (29%), fusion in 2 (6%), and skin grafting following wound breakdown for 1 (3%). Four feet (12.9%) experienced post operative wound complications, including 3 (9.68%) cases of infection and 2 (6.45%) of delayed wound healing. This study demonstrated stable clinical and radiographic outcomes over 5 years following Calcaneus Fracture Open Reduction Internal Fixation using a sinus tarsi approach, supporting its continued usage when treating intraarticular calcaneus fractures for which operative intervention is indicated.

Flatfoot Reconstruction for Painful Pediatric Idiopathic Flexible Flatfoot: Prospective Study Demonstrates Improved Alignment, Function, and Patient-reported Outcomes

BACKGROUND

This prospective study was undertaken to report outcomes following reconstructive surgery for patients with painful pediatric idiopathic flexible flatfoot.

METHODS

Twenty-five patients with pediatric idiopathic flexible flatfoot were evaluated pre- and post flatfoot reconstruction with lateral column lengthening (LCL). All patients had lengthening of the Achilles or gastrocnemius, while 13 patients had medial side soft tissue (MSST) procedures, 7 underwent medial cuneiform plantarflexion osteotomy (MCPO), and 5 had medializing calcaneal osteotomy. Measures of static foot alignment-both radiographic parameters and clinical arch height indices-were compared, as were measures of dynamic foot alignment and loading, including arch height flexibility and pedobarography. Preoperative and postoperative patient-reported outcome (PRO) scores were compared between those treated with or without MSST procedures.

RESULTS

The median subject age was 13.8 years (range: 10.3 to 16.5) at the time of surgery. All radiographic parameters improved with surgery ( P <0.001). The mean sitting arch height index showed a modest increase after surgery ( P =0.023). Arch height flexibility was similar after surgery. The mean center-of-pressure excursion index increased from 14.1% to 24.0% ( P <0.001), and the mean first metatarsal head (MH) peak pressure dropped ( P <0.001), while the mean fifth MH peak pressure increased ( P =0.018). The ratio of peak pressure in the fifth MH to peak pressure in the second MH increased ( P =0.010). The ratio of peak pressure in the first MH to peak pressure in the second MH decreased when an MCPO was not used ( P <0.002), but it remained stable when an MCPO was included. Mean scores in all PRO domains improved ( P <0.001). Patients treated without MSST procedures showed no difference in PROMIS Pain Interference scores compared to those without MSST procedures.

CONCLUSIONS

Flatfoot reconstruction surgery using an LCL with plantarflexor lengthening results in improved PROs. LCL changes but does not normalize the distribution of MH pressure loading. The addition of an MCPO can prevent a significant reduction in load-sharing by the first MH.

The Effect of Frontal Deformity at the Ankle Joint on Total Ankle Arthroplasty Revision Rate

The presence of severe coronal plane deformity in the ankle joint is widely recognized as challenging to correct by total ankle joint arthroplasty alone, necessitating additional rearfoot fusion. The primary aim of this retrospective study was to investigate the potential associations between the presence or severity of coronal tibiotalar deformities and adverse outcomes after isolated total ankle arthroplasty, such as revisions and complications. The secondary aim was to analyze the potential associations between comorbidities, demographics, and implant types, and adverse outcomes. Our study's distinctive feature was its exclusive concentration on patients with deformities centralized in the ankle joint. Chart review was performed on 496 ankles in 456 patients who had a total ankle arthroplasty by 5 surgeons from 1/1/2010 to 12/31/2019. After exclusion and inclusion criteria were applied, total of 214 ankles in 210 patients were included for data analysis. At a mean follow-up period of 3 ± 2.0 years, our cohort had 15 (7.0%) revisions and 15 (7.0%) complications. Multivariable logistic regression model showed that the presence or severity of the coronal deformity was not significantly associated with incidences of revisions or complications. Female patients had significantly lower revision rate. Otherwise, the differences in age, race, body mass index, tobacco use, presence of diabetes, chronic kidney disease, atrial fibrillation, length of surgery, or type of implant were not significantly associated with incidences of revisions or complications. Further study could be performed to analyze the extent and duration that the coronal deformity correction is maintained after total ankle arthroplasty as well as the effect of each soft tissue procedure performed with the total ankle arthroplasty.

Effect of sequential burr passes on osteotomy magnitude and calcaneal morphology in minimally invasive Zadek osteotomy

PURPOSE

This study aimed to evaluate the impact of each burr pass on degree of correction, gap size and calcaneal morphology in MIS Zadek osteotomy.

METHODS

MIS Zadek osteotomy was performed on ten cadaveric specimens using a 3.1 mm Shannon burr. After each burr pass, the osteotomy gap was manually closed, and the subsequent burr passes were carried out with the foot held in dorsiflexion, which was repeated five times. Lateral X-rays were taken before and after each burr pass. Two independent reviewers measured the dorsal calcaneal length after each burr passage, as well as changes in several calcaneal parameters including X/Y ratio, Fowler Philip angle, and Böhler angle.

RESULTS

The average decrease in dorsal calcaneal cortical length with each burr pass was as follows: 2.6 ± 0.9 mm at the 1st pass, 2.4 ± 1 mm at the 2nd pass, 2 ± 1 mm at the 3rd pass, 1.6 ± 1 mm at the 4th pass, and 1.4 ± 0.7 mm at the 5th pass. The Fowler Philip and Böhler angles consistently decreased while the X/Y ratio consistently increased following each consecutive burr pass. Interobserver reliability analysis demonstrated good agreement for all parameters.

CONCLUSION

The results revealed the trends of length and anatomical changes in the calcaneus with each burr pass. On average, a dorsal wedge resection of 10 mm was achieved after 5 burr passes. This data can aid surgeons in determining the optimal number of burr passes required for a particular amount of resection, ensuring the attainment of the desired patient-specific surgical outcome.

Imaging modalities for non-acute pathologies of the foot and ankle

Chronic foot and ankle pain, in contrast to acute traumatic injuries, presents a diagnostic challenge due to its diverse underlying causes. Accurate diagnosis often necessitates the utilization of various imaging modalities, emphasizing the importance of selecting the most appropriate one. The intricate structure of the foot, composed of multiple bones and supported by soft tissues like ligaments and plantar fascia, gives rise to a spectrum of mechanical disorders, including stress fractures, plantar fasciitis, Morton's neuroma, and more. In addition to mechanical issues, non-acute abnormalities encompass inflammatory diseases affecting tendons and joints, benign tumors, tumor-like lesions, vascular abnormalities, and others. This article reviews the indispensable role of imaging in the assessment of these conditions, with a focus on plain radiography, computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine studies, tailored to the specific clinical presentation. By providing insights into the selection and interpretation of imaging modalities, this article aims to assist clinicians in achieving accurate diagnoses and optimizing patient care for nonacute foot and ankle pathologies.

Diagnostic applications and benefits of weightbearing CT in the foot and ankle: A systematic review of clinical studies

BACKGROUND

Foot and ankle weightbearing CT (WBCT) imaging has emerged over the past decade. However, a systematic review of diagnostic applications has not been conducted so far.

METHOD

A systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines after Prospective Register of Systematic Reviews (PROSPERO) registration. Studies analyzing diagnostic applications of WBCT were included. Main exclusion criteria were: cadaveric specimens and simulated WBCT. The Methodological Index for Non-Randomized Studies (MINORS) was used for quality assessment.

RESULTS

A total of 78 studies were eligible for review. Diagnostic applications were identified in following anatomical area's: ankle (n = 14); hindfoot (n = 41); midfoot (n = 4); forefoot (n = 19). Diagnostic applications that could not be used on weightbearing radiographs (WBRX) were reported in 56/78 studies. The mean MINORS was 9.8/24 (range: 8-12).

CONCLUSION

Diagnostic applications of WBCT were most frequent in the hindfoot, but other areas are on the rise. Post-processing of images was the main benefit compared to WBRX based on a moderate quality of the identified studies.

The Association of Cavovarus Foot Deformity With an Os Peroneum

OBJECTIVE

We sought to assess whether the presence of an os peroneum is correlated with cavovarus foot alignment in patients without a neurologic explanation for their foot shape. We hypothesized that a large os peroneum would increase the power of the peroneus longus and lead to a forefoot-driven, hindfoot varus deformity.

MATERIALS AND METHODS

This was a retrospective cohort study conducted at a single institution and reviewed patients with 3 weightbearing views of the foot on plain radiography. Patients were characterized into having either no os peroneum (235), a small os peroneum (18), or a large os peroneum (23). The control group included the first 101 of the 235 patients without an os peroneum based on a power analysis of the primary outcome, which was the difference in the mean Meary's angle (lateral talo-first metatarsal angle) between groups. The kite angle (anterior-posterior [AP] talocalcaneal angle), as well as 4 other angles were measured as secondary outcomes.

RESULTS

Those with a large os peroneum had on a mean 7.7° (P < .01) more apex dorsal angulation of Meary's angle than controls, and a kite angle 4.2° varus to that of the control group. There were no differences between the small os peroneum and control groups.

CONCLUSION

These findings add to the existing literature surrounding the etiology of cavovarus foot shape and link the presence of an ossified os peroneum, an oftentimes incidental radiographic finding, to cavovarus foot deformity in those without an underlying neurologic diagnosis.

LEVELS OF EVIDENCE

Therapeutic, Level III: Retrospective Case-Control.

Imaging of osteoarthritis from the ankle through the midfoot

Ankle, hindfoot, and midfoot osteoarthritis (OA) is most commonly posttraumatic and tends to become symptomatic in younger patients. It often results from instability due to insufficiency of supportive soft tissue structures, such as ligaments and tendons. Diagnostic imaging can be helpful to detect and characterize the distribution of OA, and to assess the integrity of these supportive structures, which helps determine prognosis and guide treatment. However, the imaging findings associated with OA and instability may be subtle and unrecognized until the process is advanced, which may ultimately limit therapeutic options to salvage procedures. It is important to understand the abilities and limitations of various imaging modalities used to assess ankle, hindfoot, and midfoot OA, and to be familiar with the imaging findings of OA and instability patterns.

Long-term Impact of Planovalgus Foot on Activities of Daily Living in Patients With Down Syndrome

INTRODUCTION

Planovalgus foot (PVF) is the most common orthopaedic abnormality in children with Down syndrome (DS), and as a result these patients rarely develop an adequate plantar arch in adulthood. The present study aims to evaluate the impact of PVF on activities of daily living and participation in sports among young adults with DS and determine whether this impact is related to the degree of foot deformity based on clinical and imaging studies.

METHODS

Observational analytical study examining a database of 649 patients with DS from a pediatric referral center, identifying those individuals over age 20 years at the time of the study with a childhood diagnosis of PVF. Finally, 51 patients (102 feet) were evaluated based on clinical and imaging studies, and function was assessed using the The Foot and Ankle Outcome Score (FAOS) and the Visual Analogue Scale (VAS) pain scale. A correlation analysis was performed to determine the clinical and radiographic variables associated with functional outcomes. Linear regression models were obtained to quantify the impact of these variables on function.

RESULTS

Patients had a mean age of 26.14±3.88 years and body mass index of 24.51±4.57. Clinically, 63.65% presented grade 3 or 4 PVF, and most were flexible. Radiographically, midfoot flattening was mild-moderate in 92.16%, 58.82% had medial talo-navicular uncoverage, and 30.39% had an increased hallux valgus (HV) angle. Mean scores for all FAOS subscales were between 65 and 71% and the mean VAS score was 1.45±1.96. An association analysis revealed a tendency toward lower scores on all FAOS subscales and greater pain according to the VAS scale in more severe PVF and in cases of moderate HV with asymmetry between feet. Linear regression models showed that major contributors to functional scores were radiographic evidence of hindfoot valgus, midfoot abduction, and flattening, and HV.

CONCLUSIONS

Young adults with DS who are diagnosed with PVF in childhood have acceptable functional scores and low pain. Alteration of radiographic parameters toward flatter, more valgus and abducted feet and greater and asymmetric HV tend to be associated with worse long-term functional scores in activities of daily living and sports participation and increased pain. Therefore, non-operative management of these patients is justified, although individualized treatment is recommended.

LEVEL OF EVIDENCE

Level IV, Case series.

Ulcer occurrence on adjacent toes and hallux valgus deformity after amputation of the second toe in diabetic patients

BACKGROUND

Amputation of the second toe is associated with destabilization of the first toe. Possible consequences are hallux valgus deformity and subsequent pressure ulcers on the lateral side of the first or on the medial side of the third toe. The aim of this study was to investigate the incidence and possible influencing factors of interdigital ulcer development and hallux valgus deformity after second toe amputation.

METHODS

Twenty-four cases of amputation of the second toe between 2004 and 2020 (mean age 68 ± 12 years; 79% males) were included with a mean follow-up of 36 ± 15 months. Ulcer development on the first, third, or fourth toe after amputation, the body mass index (BMI) and the amputation level (toe exarticulation versus transmetatarsal amputation) were recorded. Pre- and postoperative foot radiographs were evaluated for the shape of the first metatarsal head (round, flat, chevron-type), the hallux valgus angle, the first-second intermetatarsal angle, the distal metatarsal articular angle and the hallux valgus interphalangeal angle by two orthopedic surgeons for interobserver reliability.

RESULTS

After amputation of the second toe, the interdigital ulcer rate on the adjacent toes was 50% and the postoperative hallux valgus rate was 71%. Neither the presence of hallux valgus deformity itself (r = .19, p = .37), nor the BMI (r = .09, p = .68), the shape of the first metatarsal head (r = - .09, p = .67), or the amputation level (r = .09, p = .69) was significantly correlated with ulcer development. The interobserver reliability of radiographic measurements was high, oscillating between 0.978 (p = .01) and 0.999 (p = .01).

CONCLUSIONS

The interdigital ulcer rate on the first or third toe after second toe amputation was 50% and hallux valgus development was high. To date, evidence on influencing factors is lacking and this study could not identify parameters such as the BMI, the shape of the first metatarsal head or the amputation level as risk factors for the development of either hallux valgus deformity or ulcer occurrence after second toe amputation.

TRIAL REGISTRATION

BASEC-Nr. 2019-01791.

Ankle Pain After Medial Opening-Wedge High Tibial Osteotomy in Patients With Knee Osteoarthritis and Concurrent Ankle Osteoarthritis

BACKGROUND

Medial opening-wedge high tibial osteotomy (MOWHTO) in patients with varus knee osteoarthritis (OA) causes changes to ankle and hindfoot alignment. However, the compensatory ability of the ankle and hindfoot varies according to the severity of ankle OA.

PURPOSE

To investigate whether the changes in ankle symptoms and ankle and hindfoot alignments differ after MOWHTO according to the severity of preoperative ankle OA.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

The data of 130 patients who were followed for ≥4 years were reviewed. Patients were classified into 2 groups according to their severity of ankle OA: group 1, modified Kellgren-Lawrence grade 0 and 1; group 2, grade ≥2. Four radiographic parameters were examined to evaluate ankle alignment: tibial plafond inclination, talar tilt, talar inclination, and tibial surface angle. The hindfoot alignment was evaluated using the varus-valgus angle (VVA) of the calcaneus. A visual analog scale (VAS) was used to evaluate ankle pain. The patient-reported outcome measure of the knee joint was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score.

RESULTS

There were 110 patients in group 1 and 20 patients in group 2. In group 2, the change in talar inclination after MOWHTO was significantly greater and the changes in tibial plafond inclination, talar tilt, and VVA were significantly smaller compared with in group 1 (all P < .05). Ankle pain VAS scores were more severe in group 2 than in group 1 pre- and postoperatively (all P < .05), and group 2 reported that ankle pain worsened postoperatively (P < .05). In both groups, knee WOMAC scores improved, and there were no differences between groups pre- or postoperatively (all P > .05). A multivariate regression analysis demonstrated that a small VVA change (odds ratio, 0.775; P = .027) and severe OA grade of the ankle joint preoperatively (Kellgren-Lawrence grades 2-4 vs 0 and 1; odds ratio, 4.241 [P = .046]) predicted increased ankle pain VAS scores after MOWHTO.

CONCLUSION

Although the patient-reported outcome measures for the knee joint improved irrespective of the presence of ankle OA, ankle pain worsened after MOWHTO in patients with ankle OA. Inadequate compensatory change in hindfoot alignment increased ankle pain in these patients.

Subtalar arthroeresis with peek endorthesis in juvanile flexible flafoot: Short-term results

A successful and minimally invasive treatment for adolescent flexible flatfoot is subtalar arthroeresis. This study examines the short-term results of subtalar arthroereisis with a new PEEK device (Pit'Stop®); additional research will be required to determine the device's true potential, but the preliminary findings are very encouraging, with a high success rate and a low complication rate (0.08).