Hallucal Sesamoids Research Articles

A novel approach to hallucal sesamoid pathology utilizing a 3D printed patient specific total sesamoid replacement implant: Case series

BackgroundSesamoidectomy can be associated with multiple complications secondary to loss of the intrinsic function of the excised sesamoid. We sought to mitigate these complications by preserving sesamoid function with a total sesamoid replacement (TSR) in lieu of sesamoidectomy. MethodPatient specific 3D printed TSR implants were designed and implanted for three patients who had exhaustively failed conservative measures. Follow up ranges from 7-36 months during which we evaluated for complications, symptom resolution, and patient satisfaction. ResultAll patients had complete resolution of pain between 3.5-12 months postop and have remained satisfied with their outcome. No evidence of the aforementioned complications was observed. ConclusionTSR may represent a viable alternative treatment option for most cases in which sesamoidectomy would otherwise be considered. Level of evidenceIV, case series.

Stress fractures of the foot - current evidence on management

Stress fractures are a consequence of repeated submaximal loads with inadequate time for recovery and biologic repair or remodelling. The foot and ankle complex (FAC) represents a common site for development of stress fractures. Whilst the overall incidence of stress fractures is low, they are prevalent in athletes and military personnel causing significant time away from sports or work. Within these populations, certain stress fractures directly correlate to specific activities.Factors that commonly influence these fractures include an acute increase in new repetitive physical activity combined with muscle fatigue, training errors or improper athletic techniques, which challenge the regenerative and remodelling capacity of bone. Depending on the site that is subject to repetitive loading, various biomechanical factors can result in abnormal concentration of forces to specific areas of the FAC resulting in stress fracture. Decreased bone marrow density (BMD) is a major biologic cause for developing stress fractures. The female athlete triad comprising eating disorder, amenorrhea and osteoporosis in competitive athletes also predisposes to stress fractures. Vitamin D deficiency is also postulated to be the cause of these fractures and may contribute to poor healing.Clinical presentation is usually with vague pain of insidious onset which worsens with activity and improves with rest. Diffuse tenderness over the affected bone is common with only a minority having any visible swelling. Plain radiographs are the first line of investigation but rarely reveal an obvious fracture. MRI scans aid in diagnosis and CT scans help in treatment and characterisation of the fracture and monitor healing.Management relates to the site of injury, which stratifies them into high or low-risk. Stress fractures of the calcaneus, cuboid and cuneiforms are classed as low-risk fractures as they usually heal with simple activity modification or short duration of non-weight bearing. Stress fractures of the navicular, talus and hallucal sesamoids are classed as high-risk fractures due to higher rates of non-union and prolonged recovery time. Metatarsal fractures can be considered high or low-risk depending on location. These warrant aggressive management, often requiring surgical intervention. Adjuncts such as vitamin D supplements, external shockwave therapy, low-intensity pulsed ultrasound therapy have been used with varying success but there remains little supportive evidence of superiority in the available literature.

43 Case Report: A Novel Technique of Reconstruction Following Second and Third Ray Amputation and Excision of Lateral Sesamoid for Synovial Sarcoma of the Foot

Abstract Synovial sarcomas primarily occur in soft tissues close to the joints and extremities. When they arise close to the hallucal sesamoids, which play a role in the static and dynamic weight process of the foot, present a management dilemma. We report a case of a soft tissue synovial sarcoma of the foot in a previously fit and healthy 17-year-old individual without any history of trauma. MRI of the foot showed the tumour near the lateral sesamoids. Histology obtained by ultrasound guidance confirmed a diagnosis of primary synovial sarcoma. After radio-chemotherapy, Patient had an en-block excision of the second and third ray of the foot as well as excision of the lateral sesamoid and lateral stabilizing structures of the first metatarsophalangeal joint with transposition of the extensor hallucis longus of the second toe to the cavity of the excised lateral sesamoid. Following recovery, with a preserved first ray, patient is still able to walk, run and tiptoe walk. Patient also remains tumour-free at 5-year follow-up. We hope that the reconstruction option can be used in selective indications to restore lateral stability of first metatarsophalangeal joint (MTPJ).

Multiple factors contributing to the metatarsal head eversion in hallux valgus deformity. A prospective study using weight-bearing CT

PurposeRecently first tarsometatarsal arthrodesis for hallux abducto valgus (HAV) has been advocated as the sole procedure to correct the multiplanar components of the deformity. However, recent debate suggests other factors such as rearfoot pronation and metatarsal torsion affect frontal plane metatarsal eversion and sesamoid positioning. Using weight-bearing CT, 12 feet (12 subjects) with HAV deformities were placed in positions of maximum rearfoot pronation and supination in order to study the effects on metatarsal eversion, sesamoid rotation/displacement, and secondarily the influence of first metatarsal torsion. Sesamoid displacement was quantified by the novel use of the sesamoid displacement angle. Principle resultsAlthough first metatarsal eversion was nearly double in the pronated versus supinated foot, the difference was not statistically significant. Therefore, the bulk of first metatarsal eversion was not secondary to rearfoot eversion. Conversely, a significant positive correlation was found between metatarsal torsion and metatarsal head eversion angles in both supinated and pronated foot positions, with the strongest correlation with rearfoot pronation. Finally, significant increases in sesamoid displacement angles were noted with pronation. Major conclusionsThe findings of the present study support the contention that multiple factors are associated with frontal plane first metatarsal eversion and sesamoid displacement. Weight-bearing CT scanning can be used to effectively evaluate the frontal plane components in HAV deformities. The sesamoid displacement angle appears to be a useful adjunct to evaluating the hallucal sesamoids. For surgical correction of the deformity, consideration should be given to pre-operative weight-bearing CT evaluation of the foot. This can illuminate the effects of rearfoot/medial column pronation and the potential influence of metatarsal torsion on the frontal plane components of this triplane deformity. In this way the potential for post-operative HAV recurrence can be minimized.

Prevalence and Distribution of Sesamoid Bones in the Region of the Forefoot among Jordanians

The sesamoid bones of the forefoot are typically found within the plantar plates of the interphalangeal (IP) and metatarsophalangeal (MTP) joints. Although rare, they are relatively implicated in some pathology including fractures, infections, arthritis, and osteonecrosis. There is an extensive variability in the reported prevalence of sesamoid bones within different populations the aim of this study was to determine the prevalence of sesamoid bones of the forefoot, their distribution and morphological variations in Jordanians according to gender and side using plain radiography. Foot radiographs were obtained from patients referred to the foot and ankle clinic at Jordanian Royal Medical Services. The sesamoids of the first MTP joint were found in all radiographs. Bipartite hallucal sesamoid was found in 3.6%, bipartite medial in 2.0 %, bipartite lateral in 1.3%, and bipartite medial and lateral in 0.3%. None of the radiographs showed a single medial or lateral hallucal sesamoid bone. Sesamoids at the second, fourth, and fifth MTP joints were observed in 1.6%, 0.4%, and 5.6%, respectively. The third MTP sesamoid was not observed in this series. A multipartite MTP sesamoid was observed at the fourth and fifth MTP joints and identified in 3.1 % of the feet. No cases were identified with multipartite sesamoid bones at the second or third MTP joints. Coincidence of sesamoid bones at two MTP joints was also observed. Hallucal IP sesamoid was observed in 1.8% and the IP sesamoids of second, third, fourth, and fifth toes were not observed in this series. A thorough knowledge of normal anatomical variants is essential to avoid unnecessary clinical workup and is implicated in anthropological and forensic studies. Further research may be needed to explore the genetic and/or environmental factors that may be attributed to the variations in the prevalence of sesamoid bones in different populations.

Ossification timeline of sesamoid bones at metatarsophalangeal joints.

Ossification timeline is a critical issue in studies regarding sesamoid bones at metatarsophalangeal (MTP) joints, but actual knowledge is still incomplete. The present study determines the cutoff age of sesamoids ossification at MTP joints. We conducted a retrospective review of radiographs of the feet from 5553 males and 3225 females between November 2005 and September 2012 to identify presence of sesamoids at 5 MTP joints and 3 variations of hallucal sesamoids. Age-specific prevalence of each presence and variations was calculated and clustered to produce latent age groups corresponding to the sesamoid ossification process in males and females, respectively. Males older than 7years of age were divided into 5 age groups (8-11, 12-15, 16-29, 30-76, and 77-92years), while females were classified into 4 age groups (8-11, 12-26, 27-76, and 77-92years). According to the characteristics of sesamoid prevalence in each age group, the pre-ossification stage was defined at age 1-7years in both genders and the ossifying stage was defined at age 8-29years in males and 8-26years in females. We also defined ossified stage as age 30-92years in male and 27-92years in females. The ossifying and ossified stages include 2 or 3 substages in both genders. A clustering analysis provided novel cutoff age points as ossification timelines for the sesamoid bones at MTP joints in males and females, which may have an impact on future sesamoid and skeletal development research.

Classification of Hallucal Sesamoid Bone Correlated with Hallux Valgus Severity.

The hallucal sesamoid bones (HSBs), having an important role in reducing load per unit area on the first metatarsal head, can be injured commonly which also affected the first metatarsophalangeal joint and the surrounding structure. Meanwhile, differences among each HSB type may be a major factor affecting the occurrence and development of HV. So far, many researchers had learned that there are three different conditions in hallucal sesamoid bone affecting the choice of clinical surgery corresponding to different solutions in clinic. Thus, it is necessary to study the anatomical morphological characteristics of the HSB which can be helpful in clinical diagnosis and treatment, especially hallux valgus (HV). 150 X-ray and three-dimensional (3D) computed tomographic (CT) images consist of 72 left and 78 right metatarsals were applied in this anatomic study between two variables and showed by a simple scatter plot. The first metatarsophalangeal joint is divided into four different types: type I (no HSB, 1.3%), type II (with one HSB, 0.07%), type IIIa (with two HSBs when THB is bigger, 28%), type IIIb (with two HSBs when FHB is bigger, 65.3%), and type IV (with three HSBs, 4.7%). There was no statistical difference between the left and right sides, except HVA, Meary, and pitch (P < 0.05); all a, b, c, d, and i have statistical difference between male and female (P < 0.05). Meanwhile, HVA and IMA and HVA and type group have a significant correlation. In summary, HVA and IMA and HVA and classification of HSBs have significant correlations. The classification and location of HSBs can be an important basis to choose operation methods and postoperation evaluation.

Early Upper Paleolithic human foot bones from Manot Cave, Israel

The transition from the Middle Paleolithic to the Upper Paleolithic in the Levant represents a major event in human prehistory with regards to the dispersal of modern human populations. Unfortunately, the scarcity of human remains from this period has hampered our ability to study the anatomy of Upper Paleolithic populations. This study describes and examines pedal bones recovered from the Early Upper Paleolithic period at Manot Cave, Israel, from 2014 to 2017. The Manot Cave foot bones include a partial, left foot skeleton comprising a talus, a calcaneus, a cuboid, a first metatarsal, a second metatarsal, a fifth metatarsal, and a hallucal sesamoid. All these remains were found in the same archaeological unit of the cave and belong to a young adult. Shape and size comparisons with Neanderthals, Anatomically Modern Human and modern human foot bones indicate a modern human morphology. In some characteristics, however, the Manot Cave foot bones display a Neanderthal-like pattern. Notably, the Manot Cave foot is remarkable in its overall gracility. A healed traumatic injury in the second metatarsal (Lisfranc's fracture) is most likely due to a remote impact to the dorsum of the foot. This injury, its subsequent debility, and the individual's apparent recovery suggest that the members of the Manot Cave community had a supportive environment, one with mutual responsibilities among the members.

Imaging Findings of Bilateral Medial Hallucal Sesamoid Insufficiency in a Marathon Runner

The absence of hallucal sesamoids is an uncommon and incidental entity, bilateral absence is rare, and few cases of symptomatic patients have been reported in literature. Most patients present with metatarsalgia limited to plantar aspect of the great toe, with aggravation of pain on walking and relief at rest. We present a unique case of ipsilateral symptomatic hypoplastic medial hallucal sesamoid and asymptomatic absence of medial sesamoid at the contralateral foot.

SESAMOID INJURIES IN PEDIATRIC AND ADOLESCENT ATHLETES PRESENTING TO SPORTS MEDICINE CLINIC

Background Sesamoid injuries of the first metatarsal phalangeal joint in athletes occur with sports that place repetitive stress on the plantar aspect of the great toe. Performing artist athletes are particularly at risk for injury given the load placed on the hallucal sesamoid bone often inherent in the activity. Risk factors may include choice of sport, volume of training, sex, bone density, BMI and biomechanical profile of the lower extremity. Hallucal sesamoid evaluation and treatment remains poorly defined in the literature. The aim of this study is to analyze all sesamoid injuries presenting to a sports medicine clinic. The goal of the study is to increase understanding of the injury profile, diagnostic evaluation, treatment regime, and return to sport of athletes with hallucal sesamoid injuries. The long-term goal is to develop evaluation and treatment algorithms that serve to guide clinical decision-making, and improve time to return to sport. Methods A comprehensive retrospective chart review was conducted of athletes presenting to a tertiary level sports medicine clinic located within a pediatric medical center. Electronic medical records were searched using the search term sesamoid. To be included in the study, the injury had to definitively involve the hallucal sesamoid and be related to sports participation. Exclusion criteria included patients with a chronic disease or condition that might affect bone healing or confuse the diagnosis of sesamoid injury, prior history of surgery to the foot, and insufficient management records. Descriptive statistics were used to analyze outcome variables including specific diagnosis, clinical prognoses, diagnostic imaging tools and treatment types. Additionally, a correlation analysis was performed for time from pain onset to first clinic visit, and time to return to participation. Little or no correlation was considered 0.00-0.25, weak correlation was considered 0.25-0.50, moderate correlation was considered 0.50-0.75 and strong correlation was considered 0.75 -1.00. Results 326 athletes with 359 hallucal sesamoid injuries were identified. The mean age of the cohort was 15.8 ± 3.8 years (median: 15.3, 95% CIs: 15.46 – 16.24); 86% (n=309) were female and 14% (n=50) of the injuries were male. The mean BMI of the cohort was 21.28 ± 3.5 mg/kg2. Table 1 presents the sports for the athletes in the cohort. The leading sports included 40% (n=144) dance, 13% (n=48) running, and 13% (n=47) soccer. Activities that top the list for females include dance 44% (n=137) and running 13% (n=39). In comparison, male athletes participated in soccer (20%, n=10), running (18%, n=9), and football (10%, n=5) as well as other diverse sports. The most common injuries across both sexes were sesamoiditis (30%, n=107), followed by sesamoid stress fracture (13%, n=46). Table 2 Where self-reported data on dance/sport practice time was recorded, 31% (n=65) reported practicing 10-15 hours per week. Figure 1 The average reported time between injury or the onset of pain to the first clinic visit was 143 days (median: 42, 95% CIs:116.87-169.15). The mean time between pain onset and first clinic visit was greater for female athletes as compared to male athletes (146 days and 119 days). The average time from first presentation to clinic to returning to participation was 115 days (median: 72, CIs:100.7-129.49). Spearman’s rho demonstrated a strong correlation between time from pain onset to first clinic visit and the time to return to participation in both males (? (rho) = 0.82, p &lt; 0.001) and females (? = 0.79, p &lt; 0.001). Males experienced a shorter duration from the first clinic visit to return to participation (mean: 72 days, median 33), than females (mean: 121 days, median 77). The most common diagnostic imaging modalities used were radiographs (72.14%, n=259) and MRI (56.55%, n=203). In both males and females the most common initial treatments included a combination of: walking boot (51.53%, n= 185), physical therapy (38.72%, n=139), and activity modification (34.82%, n=125). These remained the most popularly prescribed treatments in the second and third treatments as well. Conclusions/significance Female athletes participating in dance and running, and male soccer, running and football athletes lead the list for injury to the hallucal sesamoid. Sesamoiditis and sesamoid stress fracture were the leading diagnoses in this cohort. Athletes who presented to clinical attention sooner also returned to sport/dance sooner when compared to athletes who delayed seeking medical attention. Continued research will serve to support anticipatory guidance and education surrounding hallucal sesamoid clinical presentation and need for timely evaluation and treatment in order to minimize time loss from sport/performing artist activity. [Table: see text][Table: see text][Figure: see text]

STEWARDS OF THE GENOME: ETHICAL ISSUES RELATED TO DATA PRIVACY AND SHARING IN PSYCHIATRIC GENETICS RESEARCH

The aim of the present study was to determine the effectiveness of nonsurgical treatment for osteomyelitis of the hallucal sesamoids. Osteomyelitis of the hallucal sesamoids in young and healthy patients is rare and might originate from hematogenous spread or after a puncture wound. In diabetic patients with peripheral neuropathy, it often results from direct contiguous seeding from adjacent ulceration. The superiority of surgical versus nonsurgical therapy is still debated. In our institution, all patients presenting with osteomyelitis of the hallucal sesamoids are first treated nonsurgically but eventually usually require a surgical procedure. We reviewed 18 patients with a clinical and radiologic diagnosis of osteomyelitis of the hallucal sesamoids treated in our institution during a 13-year period (from January 2000 to December 2012). The inclusion criteria were a signal alteration on magnetic resonance imaging or bone lesions on computed tomography or conventional radiographs, combined with a deep ulcer with a positive probe-to-bone test. Nonsurgical therapy consisted of frequent wound treatment, immobilization, offloading in a cast or other orthotic device, and oral antibiotics. Of the 18 patients, 11 had diabetes, 16 had peripheral neuropathy, 11 had peripheral arterial disease, and 5 had immunosuppression. After a period of nonsurgical therapy ranging from 4 weeks to 9 months, 15 of 18 patients required surgical excision, internal resection, or amputation. In this patient population, we no longer consider nonsurgical therapy a viable option. Patients should be advised, before starting nonsurgical treatment, that the therapy will be long and demanding and very often results in a surgical procedure.

A radiological study of anatomical variants of hallux sesamoids

Abstract Background and Aims: Hallux sesamoid bones forms an integral part of the first metatarsophalangeal joint for stability during weight bearing. Hallux sesamoids are paired bones located on the plantar aspect of the first metatarsal head within the flexor hallucis longus tendon. Hallucal sesamoids vary in shape and size; can be single, double, bipartite and multipartite. Traumatic insult to the hallux sesamoids can lead to fracture &amp; dislocation, while majority of symptomatic hallux sesamoids can be treated non-surgically; certain specific injuries require a high index of suspicion, careful management, and surgical intervention. Hence present study was taken up to know the incidence, presence/absence, number and partition of hallux sesamoid to enlighten the surgeons and radiologists in early diagnosis and treatment of cases presenting with history of trauma, pain and fractures of foot. Methods: Retrospective radiographic study on the incidence, anatomical variants &amp; distribution ofhallux sesamoids inlOOO radiographs ofthe foot. Result: Hallux Sesamoid bones were seen plantar to first metatarsal head in 994 radiographs [99.4%], while the absence ofHallucal sesamoids were noted in 6 radiographs [0.6%], Single Hallucal sesamoid were noted in 9 radiographs [0.9%], medial bipartition was noted in 20 radiographs [2%], lateral bipartition was noted in 15 radiographs [1.5%]. Conclusion: Knowledge regarding hallux sesamoids helps us in differentiating the various conditions arising out of fractures of foot bones with overlapping signs and symptoms, from actual involvement of sesamoid bone itself, which assists in the early diagnosis and management of foot pathologies.

Epidemiological profile of sesamoid disorders of the first metatarsophalangeal joint

Objective: The objective of this study is to describe the epidemiological characteristics of patients with sesamoid disorders in a sample of patients treated in the Brazilian public health system. Methods: A retrospective study was performed by reviewing the electronic charts of foot and ankle outpatient consultations over the past 5 years, analysing variables such as sex, age, occupation, ethnicity, participation in sports, laterality, and affected sesamoid (medial or lateral). Results: Abnormalities in hallucal sesamoids occur more frequently in women (63/108), during the third decade of life (56/108), and in the medial sesamoid (74/108); 65.7% of the sample with these abnormalities participated in physical activity regularly. No significant relationship was observed with laterality or occupation. Conclusion: The most commonly affected patients were females, with a mean age of 23.7 years, who participated in physical activity frequently; the right side and medial sesamoid bone were the most commonly affected sites.&#x0D; Level of Evidence II; Prospective Study.

A radiological study of anatomical variants of hallux sesamoids

Background and Aims: Hallux sesamoid bones forms an integral part of the first metatarsophalangeal joint for stability during weight bearing. Hallux sesamoids are paired bones located on the plantar aspect of the first metatarsal head within the flexor hallucis longus tendon. Hallucal sesamoids vary in shape and size; can be single, double, bipartite and multipartite. Traumatic insult to the hallux sesamoids can lead to fracture & dislocation, while majority of symptomatic hallux sesamoids can be treated non-surgically; certain specific injuries require a high index of suspicion, careful management, and surgical intervention. Hence present study was taken up to know the incidence, presence/absence, number and partition of hallux sesamoid to enlighten the surgeons and radiologists in early diagnosis and treatment of cases presenting with history of trauma, pain and fractures of foot. Methods : Retrospective radiographic study on the incidence, anatomical variants & distribution of hallux sesamoids in1000 radiographs of the foot. Result: Hallux Sesamoid bones were seen plantar to first metatarsal head in 994 radiographs [99.4%], while the absence of Hallucal sesamoids were noted in 6 radiographs [0.6%], Single Hallucal sesamoid were noted in 9 radiographs [0.9%], medial bipartition was noted in 20 radiographs [2%], lateral bipartition was noted in 15 radiographs [1.5%]. Conclusion: Knowledge regarding hallux sesamoids helps us in differentiating the various conditions arising out of fractures of foot bones with overlapping signs and symptoms, from actual involvement of sesamoid bone itself, which assists in the early diagnosis and management of foot pathologies.

Incidence and anatomical variability of accessory and sesamoid bones of the foot

Aim: We aimed to assess the incidence, mean size, patterns, and types of accessory and sesamoid bones of the foot using computed tomography. Material and Methods: A total of 814 non-contrast-enhanced computed tomography images of the foot obtained from 717 patients between October 2015 and January 2018 were investigated retrospectively. Images acquired in the original axial plane were used to perform multiplanar reconstruction in the coronal or sagittal planes. Incidence, mean size, patterns, and types of accessory and sesamoid bones were evaluated in all images. Results: Accessory bones were detected in 387 (47.5%) non-contrast-enhanced computed tomography scans from 326 patients (45.4%). Sixty-seven patients (9.3%) showed accessory bones on both sides; 133 patients (18.5%), only on the right side; and 126 patients (17.5%), only on the left side. The most common accessory bones of the foot were the os naviculare accessorium (24.8%), os trigonum, (20.3%), os peroneum (14.6%), os intermetatarseum (10.6%), os supranaviculare (3.1%), os supratalare (1.9%), and os vesalianum (1.5%). The hallucal sesamoid bone was observed in all patients, while the interphalangeal sesamoid bone was observed in 34.6% of the patients. Conclusions: The computed tomography scans provided a detailed overview of the characteristics of accessory and sesamoid bones, and the incidence of these bones in our patients was higher than those reported in previous radiographic studies. Our findings can facilitate the diagnosis and management of disorders involving these bones.

Effect of Bipartite Hallucal Sesamoid on Hallux Valgus Surgery.

Bipartite hallucal sesamoids are often found in patients with hallux valgus. However, it is unknown whether bipartite hallucal sesamoids affect the results of hallux valgus surgery or not. The purpose of the present study was to evaluate the outcomes of chevron osteotomy for hallux valgus with and without bipartite hallucal sesamoid. A total of 152 patients (168 feet) treated with distal or proximal chevron osteotomy for hallux valgus constituted the study cohort. The 168 feet were divided into 2 groups: bipartite hallucal sesamoid (31 feet) and without bipartite hallucal sesamoid (137 feet). Hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), tibial sesamoid position, and first metatarsal length were measured for radiographic outcomes and the American Orthopaedic Foot & Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal (MTP-IP) score was measured for clinical outcomes. All radiographic measurements and the AOFAS score showed significant ( P < .05) improvement at the time of final follow-up compared with preoperative measurements in both groups. No significant differences ( P > .05) were found between the 2 groups in terms of HVA, IMA, DMAA, tibial sesamoid position, metatarsal shortening, and AOFAS score on final follow-up. This study suggests that bipartite hallucal sesamoids do not affect the results of hallux valgus surgery. Level III, retrospective comparative study.

Evaluation of the 1st metatarso-sesamoid joint using standing CT — The Stanmore classification

BackgroundLittle is understood about the role that relative sesamoid displacement and chondral wear have on outcome after hallux valgus (HV) surgery. All existing methods to evaluate relative sesamoid displacement have limitations and furthermore, there have been no radiographic studies evaluating metatarso-sesamoid joint wear. Standing CT scan circumvents many of the existing problems in evaluation of relative sesamoid displacement, and also enables the first radiographic study assessing metatarso-sesamoid joint wear. MethodsFifty feet (in 43 patients) with symptomatic HV (Group A) were compared with a control group of 50 feet (50 patients) (Group B). All images were standardised to enable reproducible measurements. The hallux valgus angle, Intermetatarsal angle, sesamoid rotation angle, sesamoid position and metatarso-sesamoid joint space were measured in all patients. ResultsThe intra and inter-observer reliability correlation showed that the standing CT assessment of sesamoid position (1.000), rotation (0.991) and metatarso-sesamoid joint space (0.960) were highly reproducible.There was a highly significant difference (p<0.0001) in sesamoid position, sesamoid rotation and metatarso-sesamoid joint space between Group A and Group B. ConclusionsStanding CT has been shown to be a reproducible and accurate method of assessing the relative sesamoid displacement and metatarso-sesamoid joint space narrowing. The results have been used to propose a novel standing CT based classification of hallucal sesamoids, considering the degree of displacement and wear. This classification may ultimately facilitate research to provide new insight into the effect relative sesamoid displacement and chondral wear have on outcomes from hallux valgus surgery.

A new insight into the fabella at knee: the foetal development and evolution.

Using longitudinal semiserial sections of 12 lower extremities from 8 human foetuses at 15-18 weeks, we compared foetal morphologies of the knee in specimens with and without fabellae. We also compared the fabella, if present, with the hallucal sesamoid in the same foetus. Cartilaginous fabella, positive for versican and tenascin by immunohistochemistry, was found in 5 of the 8 foetuses. This structure was embedded in a thick and tight lateral fibrous band, providing a common origin of the plantaris muscle and the lateral head of the gastrocnemius muscle. The plantaris was covered by the lateral head of the gastrocnemius, but these 2 muscles were separated by a distinct fascia or space. Notably, the foetal fabella did not attach to the joint capsule. In the 3 specimens without fabellae, the lateral fibrous band was thin, containing a fibrous mass, negative for versican and tenascin, in place of the fabella. The "medial" head of the gastrocnemius faced or covered the plantaris, while the lateral head was continuous with the plantaris. A hallucal cartilaginous sesamoid, positive for versican and tenascin, was present in all 8 specimens. It carried a flat surface facing the joint cavity and was covered by tendons of the short muscles of the foot. Because of the difference in topographical relation of muscles between specimens with or without fabella, rather than mechanical stress to the tendon, fabella development may require a distinct plantaris muscle independent of the gastrocnemius. We discussed about an evolutionary aspect of the fabella and plantaris muscle.

Correlation between hallux valgus angle and hallucal sesamoid position on Méary Radiographic Incide

Correlation between hallux valgus angle and hallucal sesamoid position on Méary Radiographic Incide

Prevalence, morphological variation and ossification of sesamoid bones of the forefoot: a retrospective radiographic study of 8,716 Chinese subjects

Background and Aim: Previous studies provided evidence of a genetic basis for the occurrence of sesamoids bone in the foot among different ethnic populations. However, information for the Chinese population has not been previously reported. Therefore, the aim of our study was to determine the distribution, morphological variation and ossification timeline of sesamoid bones of the forefoot in a large sample of the Chinese population. Methods: Antero-posterior (AP) and oblique radiographs of 4,417 left and 4,299 right feet obtained from 8,716 patients in the Hebei province of Northern China, and retrospectively examined for the presence of sesamoid bones, identified as a small oval bone plantar to each metatarsophalangeal (MTP) joint and the first interphalangeal (IP) joint. Results and Conclusions: The prevalence rate of a sesamoid bone associated with the first to fifth MTP joints and the first IP joint was 99.96%, 3.08%, 0.39%, 0.69%, 8.94%, and 59.22%, respectively. Moreover, a morphological variation in hallucal sesamoids was identified in 12.09% of feet, with variations classified into three distinct types according to bone size and the number of ossification centers. Ossification begins in the hallucal MTP and IP joints at approximately 8 years of age, with the final ossification center being evidence for the sesamoid bone of the fourth MTP joint at 28 years of age. Relevance for patients: Our study provides important anatomical data regarding the prevalence of sesamoid bones in the forefoot of a large population of Chinese adult and pediatric patients for use in clinical practice and research in forensic science and anthropology.