The etiology of hallux rigidus is still unknown and elucidating targeted factors to prevent hallux rigidus or improve treatment outcomes is essential. An association between flexor hallucis longus (FHL) tendon tightness and hallux rigidus development has been suspected; however, the characteristics of the FHL tendon in the hallux rigidus remain unclear. This study aimed to explore the quality of the FHL tendon and the morphological characteristics of the FHL tendon groove at the talus and sustentaculum tali in the pathogenesis of hallux rigidus.

Twenty-one feet with hallux rigidus and 15 feet without hallux rigidus were retrospectively reviewed. The ratio of the FHL tendon groove depth to the FHL tendon anteroposterior diameter (groove/tendon ratio), Hounsfield unit (HU) values of the cancellous bone below the FHL tendon groove to those of the navicular (groove HU ratio) were measured using computed tomography at the talus and sustentaculum tali. The ratio of HU values inside the FHL tendon to those inside the tibialis anterior tendon (tendon HU ratio) were measured at the FHL tendon groove of the talus, that of the sustentaculum tali, and below the sesamoids.

The depth of the FHL tendon groove, groove/tendon ratio, and groove HU ratio were significantly larger in the hallux rigidus group; the FHL tendons of the hallux rigidus group were deeply fitted into the FHL groove than those of the control group. The tendon HU ratio was significantly smaller in the hallux rigidus group.

The FHL tendon in the hallux rigidus can be more constrained at the FHL groove of the talus and sustentaculum tali, and its quality can change compared to that in healthy feet. Tightness of the FHL tendon should be considered when treating hallux rigidus.

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Background: Hallux limitus (HL) is a condition marked by the restricted dorsiflexion of the first metatarsophalangeal joint, causing pain and functional limitations, especially during the propulsive phase of walking. This restriction affects the gait, particularly in the final phase, and impairs foot stability and support. HL is more common in adults and leads to biomechanical and functional adaptations. The purpose of this study was to investigate the differences in the center of pressure between subjects with hallux limitus and those with healthy feet. Methods: A total of 80 participants (40 with bilateral HL and 40 healthy controls) aged 18 to 64 were selected from a biomechanics center at the Universidade da Coruña, Spain. The gait analysis focused on three key phases: initial contact, forefoot contact, and the loading response. Data were collected using a portable baropodometric platform and analyzed using IBM SPSS Statistics 29.0.2.0; statistical significance was set at p < 0.05, with a 95% confidence interval. Results: The gait analysis indicated that the case group exhibited statistically significant differences, showing lower values in the left foot load response during the foot contact time (77.83 ± 40.17) compared to the control group (100.87 ± 29.27) (p = 0. 010) and in the foot contact percentage (p = 0. 013) during the stance phase (10.02 ± 5.68) compared to the control group (13.05 ± 3.60). Conclusions: Bilateral HL causes subtle gait changes, with individuals showing greater contact time values in the total stance phase versus the control group. Early detection may improve quality of life and prevent complications.

Viscosupplementation consists of intraarticular hyaluronic acid injections applied to treat pain and improve joint mobility. The objective of the study was to analyze the improvement of the range of mobility of the first metatarsophalangeal joint with a single dose of cross-linked hyaluronic acid.

Ten fresh frozen specimens of feet sectioned below the knee were selected. Before and after the infiltration procedure, the range of flexion was calculated for all specimen's metatarsophalangeal joints. To detect complications due to the procedure, five feet were dissected and five were sectioned with a diamond saw.

The range of the first metatarsophalangeal joint flexion differences between the preoperative and the postoperative period was as follows: (1) 47° (range, 37-51.5) to 58° (range, 49-69.5) degrees of loaded dorsiflexion (p > 0.006); (2) 41° (range, 40-51.5) to 58° (range, 52.5-66.5) degrees of unloaded dorsiflexion (p > 0.009); and (3) 14° (range, 10.5-24.25) to 16° (range, 14.25-28.5) degrees of unloaded plantarflexion (p > 0.083). No injuries of anatomical structures were observed either by anatomical dissection or in the anatomical sections.

The results obtained in this viscosupplementation study demonstrate the improvement of the range of mobility of the first metatarsophalangeal joint without evidence of extravasation and lesions of the periarticular anatomical structures.

Knee osteoarthritis (KOA), hallux valgus (HV) and hallux rigidus (HR) are common musculoskeletal problems of the lower extremities. However, their underlying causal relationships are unclear. This study attempts to clarify the cause-and-effect relationship between KOA and the two common hallux deformities (HV and HR).

The summary-level statistics for KOA, HV, and HR were collected from genome-wide association studies (GWAS). The causal analysis of KOA on HV or HR was carried out using two-sample Mendelian randomization (MR). In order to assess the robustness of the MR results, sensitivity analyses were performed. In addition, multivariable MR (MVMR) was implemented to assess the influence of KOA in causation as well as calibrate the effect of anthropometric characteristics. Supplementary backward MR analysis was conducted to determine the causal effect of hallux diseases on KOA.

The univariable analysis indicated that KOA has a causative influence on HR (odds ratio [OR] = 1.29, 95% confidence interval [CI] = 1.18-1.41, P = 2.25E-8) and HV (OR = 1.43, 95% CI = 1.21-1.68, P = 2.76E-5). In the backward MR analyses, hallux deformities did not appear to be the cause of KOA. In the MVMR analysis, after jointly adjusting for the effects of waist-to-hip ratio (WHR), waist circumference (WC), hip circumference (HC) and BMI, the causal impact of KOA on HV and HR remained robust.

In this study, the genetic causality between KOA and increased risk of hallux deformities (HV and HR) is established, which can provide evidence-based recommendations for reducing the incidence of hallux deformities in KOA patients. Further high-level studies are warranted to validate the associations and explore its broader implications.

Hallux rigidus is a degenerative arthritic condition affecting the first metatarsophalangeal joint. Prevalence in patients aged 50 years and above is estimated at 20% to 30%, with a portion being symptomatic. Conservative treatment's efficacy is linked to initial pain levels; though shoe modifications and insoles are commonly recommended, their true effectiveness lacks strong evidence. Injection therapy, including corticosteroids and hyaluronic acid, demonstrates varied outcomes, with about 50% of patients undergoing surgery within 1 to 2 years. The condition's etiology remains elusive, but recent biomechanical hypotheses hold promise.

First metatarsophalangeal (MTP) joint fusion, or arthrodesis, has been a cornerstone treatment for advanced joint degeneration since the 1950s, benefiting not only older patients but also younger individuals. The procedure boasts favorable long-term outcomes and a low rate of revision when fusion is successful. However, complications such as interphalangeal arthritis may occur, and nonunion or malunion can necessitate revision. While the first MTP fusion provides significant relief, its applicability varies, underscoring the need for careful patient selection.

The classification systems of hallux rigidus, including the Coughlin and Shurnas, Hattrup and Johnson, Regnauld, and Roukis classifications, allow for a comprehensive understanding of the condition's severity and aid in informed treatment decisions. The common techniques of radiological imaging, such as standard plain film radiographs, MRI, magnetic resonance arthrography computed tomography (CT), weightbearing CT, and ultrasound, which enable accurate assessment of joint degeneration and associated pathologies for optimal patient care, are reviewed.

First metatarsal phalangeal (MTP) joint arthrodesis has been employed for decades for pain related to arthritis and other associated abnormalities. Despite the commonality of the procedure there continues to be questions regarding functional expectations following the procedure especially when employed for correction of hallux valgus deformity. We surveyed 60 patients who had a tri plane MTP joint arthrodesis at mean 28.4 months (median 27.8) regarding their activities of daily living and sports activity through a direct conversation. Secondary endpoints assessed were return to activity, deformity correction and arthrodesis healing rate based on chart review and weightbearing radiographs. The primary outcomes showed robust return to all activities of daily living with 96.7% able to walk without restrictions and or pain, 98.3% were able to walk at a normal pace and 95% responded that loss of motion of their big toe did not affect their daily function. Regarding return to sports all patients that participated in sports before surgery resumed participation after with a trend toward increased sports activity. Early return to walking in a fracture boot was noted in this cohort at mean 4.1 days, return to athletic shoe at mean 6.3 weeks and full unrestricted activity at mean 13.3 weeks with no non-unions identified on radiographic or clinical exam. Deformity correction of the typical components of hallux valgus deformity was similar to previously published studies. This data set supports the hypothesis that patients undergoing first MTP joint arthrodesis can expect rapid and full return to activities of daily living and sports with a low complication rate.

Background and Objetives: The foot is a part of the body's kinetic chain and needs to be efficient during the entire gait cycle. Electronic Sensor Gait analysis is useful and an important tool within the area of podiatry to assess the physical state of patients that helps the comprehensive intervention in situations where the daily activity is limited. The aim of this research is to evaluate if the presence of a hallux limitus (HL) can alter gait space-time parameters and consequently can affect the take-off phase of the gait and the limitation of the range of motion (ROM) of the hallux. Materials and Methods: A case-control study was designed to verify whether there are alterations in the spatiotemporal parameters of the gait cycle between subjects with structural HL compared to the group of subjects with a normal hallux range. A total of n = 138 participants, cases (68 HL subjects) and healthy controls (70 subjects) were studied using an OptoGait LED sensor system to identify gait imbalances using OptoGait photocell gait analysis sensors. Results: Significant differences were found between the two groups with respect to stride length, gait cycle duration in seconds (for both feet) and for total stride and load response (p < 0.05). Conclusions: The limitation of the Hallux ROM may alter the normal gait patterns measured with an Optogait system. The early identification and treatment of gait disturbances due to HL are important to achieve normal gait physical activity to maintain a healthy lifestyle.

Introduction Hallux rigidus (HR) is a degenerative condition affecting the first metatarsal phalangeal joint, causing stiffness and pain. Surgery is indicated for those who have failed a trial of conservative management. The purpose of this paper is to evaluate the functional outcomes at short and medium term after surgery for HR. Methods All patients who underwent surgical treatment for HR between 2017 and 2022 at the time of this study were identified and invited to return for a follow-up evaluation. Outcomes were assessed by comparison of pre-operative and post-operative visual analogue scale (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) scores. Results A total of 26 patients were included in our study with a mean follow-up of 31 months. There was a mean improvement in VAS score by 5.6 (p-value < 0.0001) and 5.7 (p-value = 0.0012) in patients who underwent joint-preserving (JP) and joint-sacrificing (JS) surgery, respectively. Patients who underwent JP surgery had a mean increase of 28.1 points (p-value < 0.0001) in the AOFAS Hallux score, while patients who underwent JS surgery had a mean increase of 27.29 points (p-value = 0.0066). Conclusion Functional outcomes after surgical management for HR are good at short- and medium-term follow-up. Good outcomes are seen with both JP and JS procedures. JP procedures should be considered as a first-line surgical option for HR as it allows revision procedures if required.

The objective of this systematic review was to determine the prevalence of hallux valgus (HV) in the general population by conducting a review and meta-analysis of existing studies. Published articles on the incidence of HV were systematically searched and evaluated on reputable medical databases such as PubMed. The keywords "the prevalence of hallux valgus and/or bunions"were used to create the search syntax on the various databases. Data were gathered on prevalence, population under study, and methodology. A total of 11 articles that met the search criteria were identified and included in this review for a total of 10,886 participants across the studies. The pooled prevalence of HV across the studies was3.75 (95% confidence interval = 0.388-0.517). Therefore, the prevalence varied widely across the studies reviewed. Prevalence was observed to be high among females and increased with risk factors such as body mass index, which were identified as significant across the studies. This review was limited by insufficient data and the lack of a standard HV diagnosis method. Therefore, a standard HV diagnosis tool is recommended.

First metatarsalphalangeal (MTP) joint arthrodesis has been employed for decades for pain related to arthritis and other associated abnormalities. Despite the commonality of the procedure there continues to be questions regarding functional expectations following the procedure especially when employed for correction of hallux valgus deformity. We surveyed 60 patients who had a triplane MTP joint arthrodesis at mean 28.4 months (median 27.8) regarding their activities of daily living and sports activity through a direct conversation. Secondary endpoints assessed were return to activity, deformity correction and arthrodesis healing rate based on chart review and weightbearing radiographs. The primary outcomes showed robust return to all activities of daily living with 97% able to walk without restrictions and or pain, 98% were able to walk at a normal pace and 95% responded that loss of motion of their big toe did not affect their daily function. Regarding return to sports all patients that participated in sports before surgery resumed participation after with a trend toward increased sports activity. Early return to walking in a fracture boot was noted in this cohort at mean 4.1 days, return to athletic shoe at mean 6.3 weeks and full unrestricted activity at mean 13.3 weeks with no non-unions identified on radiographic or clinical exam. Deformity correction of the typical components of hallux valgus deformity was similar to previously published studies. This data set supports the hypothesis that patients undergoing first MTP joint arthrodesis can expect rapid and full return to activities of daily living and sports with a low complication rate.