Easy to gain but hard to lose: the evolution of the knee sesamoid bones in Primates-a systematic review and phylogenetic meta-analysis.

Sesamoids are variably present skeletal elements found in tendons and ligaments near joints. Variability in sesamoid size, location and presence/absence is hypothesized to enable skeletal innovation, yet sesamoids are often ignored. Three knee sesamoids-the cyamella, medial fabella and lateral fabella-are present in primates, but we know little about how they evolved, if they are skeletal innovations, or why they are largely missing from Hominoidea. Our phylogenetic comparative analyses suggest that sesamoid presence/absence is highly phylogenetically structured and contains phylogenetic signal. Models suggest that it is easy to gain but difficult/impossible to lose knee sesamoids and that the fabellae may have similar developmental/evolutionary pathways that are distinct from the cyamella. Sesamoid presence/absence is uncorrelated to the mode of locomotion, suggesting that sesamoid biomechanical function may require information beyond sesamoid presence, such as size and location. Ancestral state reconstructions were largely uninformative but highlighted how reconstructions using parsimony can differ from those that are phylogenetically informed. Interestingly, there may be two ways to evolve fabellae, with humans evolving fabellae differently from most other primates. We hypothesize that the 're-emergence' of the lateral fabella in humans may be correlated with the evolution of a unique developmental pathway, potentially correlated with the evolution of straight-legged, bipedal locomotion.

Medial sesamoid position in moderate to severe hallux valgus: Correlation between three radiographic measurements.

BACKGROUND: In hallux valgus surgery, it is essential to accurately assess the position of the sesamoids both pre- and postoperatively. Weight-bearing foot anteroposterior, tangential sesamoid, and semi-weight-bearing computed tomography axial views are radiographic methods used to assess the medial sesamoid position. This study aimed to measure the medial sesamoid position and evaluate the correlation between these three radiographic methods. METHODS: This retrospective study comprised 59 feet from 49 patients who underwent hallux valgus surgery. The mean age of patients was 54.6 (range, 22-70) years. We took preoperative and postoperative measurements using the weight-bearing anteroposterior, tangential sesamoid, and semi-weight-bearing computed tomography axial views to assess the medial sesamoid position. RESULTS: The mean grades of the medial sesamoid position preoperatively and 6 months postoperatively were 2.5 and 0.8, 1.6 and 0.4, and 1.3 and 0.3 points based on the anteroposterior, tangential sesamoid, and computed tomography axial views, respectively (P < 0.001). Preoperatively, there was a strong positive correlation between the computed tomography axial and tangential sesamoid views (P < 0.001, r = 0.645) and anteroposterior and computed tomography axial views (P < 0.001, r = 0.468). In contrast, the tangential sesamoid and anteroposterior views showed a weak positive correlation (P = 0.03, r = 0.283). Six months postoperatively, there was a positive correlation between the computed tomography axial and tangential sesamoid views (P < 0.001, r = 0.473), anteroposterior and computed tomography axial views (P < 0.001, r = 0.470), and tangential sesamoid and anteroposterior views (P < 0.001, r = 0.480). CONCLUSIONS: We observed that the anteroposterior view exhibited a higher degree of medial sesamoid position displacement than the computed tomography axial and tangential sesamoid views. For the preoperative evaluation of the medial sesamoid position, the correlation between the computed tomography axial and tangential sesamoid views was stronger than that between the tangential sesamoid and anteroposterior views. However, all three views showed strong correlations postoperatively.

Hallux Valgus: The Influence of Intersesamoid Crista's Osteoarthritis on Frontal Plane Pronation.

A frontal plane metatarsal rotational (pronation) has been documented in a high percentage of hallux valgus patients. Pathoanatomical concepts leading to pronation are still debated. Nevertheless, there is no consensus on how to measure this component of the deformity. The aim of the present study was to find potential associations between sesamoid's crista osteoarthritis and the frontal plane deformity in HV cases. Our study showed a moderate correlation between the crista's OA and the intermetatarsal angle (IMA), the hallux valgus angle (HVA) and the alpha angle. In severe hallux vulgus deformed specimens, with an eroded intersesamoid crista, frontal plane pronation was not as prevalent nor severe as in those without osteoarthritic degeneration. Severe hallux valgus cases with a completely eroded crista, showed lower pronation, and higher IMA, when compared to specimens with a preserved anatomy. This brings to light the intersesamoid crista's unique function in retaining the IMA. Understanding the role the frontal plane plays in hallux valgus' biomechanics and in its radiographic appearance is vital to change the current paradigm.

Evaluate the Influencing Factors of Congruency of the First Metatarsophalangeal Joint in Hallux Valgus Based on Weightbearing CT.

The purpose of this study was to explore the difference between congruency and incongruency of the first metatarsophalangeal (MTP) joint in hallux valgus using weightbearing CT (WBCT) and to identify the risk factors for incongruency. From January 2019 to January 2021, WBCT scans were retrospectively analyzed for 110 (191 feet) consecutive patients. According to whether the metatarsal articular surface and phalanx articular surface were parallel, they were divided into congruency (73 feet) and incongruency groups (118 feet). The age, intermetatarsal angle (IMA), hallux valgus angle (HVA), distal metatarsal articular surface angle (DMAA), first metatarsal coronal pronation angle (α angle), tibial sesamoid 7 positions (TSP), and tibial sesamoid coronal grading (TSCG) were compared between the 2 groups. Binary logistic regression was used to analyze the influencing factors of incongruency. Receiver operating characteristic (ROC) curve analysis was applied to determine the cutoff value. There were significant differences in IMA, HVA, DMAA, α angle, age, TSP, and TSCG between congruency and incongruency groups (p < .05). Binary logistic regression analysis showed that TSCG, HVA, α angle were the influencing factors of incongruency. ROC curve analysis demonstrated that the cutoff values for incongruency were 1 position for TSCG (sensitivity: 0.835; specificity: 0.884) with the area under curve (AUC) of 0.892, 30° (sensitivity: 0.795; specificity: 0.812) for HVA with the AUC of 0.878, and 24° (sensitivity: 0.530; specificity: 0.797) for α angle with the AUC of 0.686. Incongruency of the first MTP joint indicated a more severe hallux valgus, and was associated with increased HVA, α angle, and TSCG.

Automatic Hardy and Clapham's classification of hallux sesamoid position on foot radiographs using deep neural network.

BACKGROUND: There is currently no deep neural network (DNN) capable of automatically classifying tibial sesamoid position (TSP) on foot radiographs. METHODS: A DNN was developed to predict TSP according to the Hardy and Clapham's classification. A total of 1554 foot radiographs were used for model development. The validation of the model was conducted using radiographs obtained from 113 consecutive first-visit patients of our foot and ankle clinic. On these 113 radiographs, TSP was independently classified by three foot and ankle surgeons and the DNN, and their results were compared. The weighted kappa value of TSP between the DNN prediction and the median of the three surgeons (KAI) was calculated. RESULTS: The KAI was 0.95 (95 %CI: 0.85- 1.00), indicating sufficient consistency between the surgeons and the DNN. CONCLUSIONS: We have developed a DNN for automated TSP classification that demonstrates sufficient consistency with foot and ankle surgeons. LEVELS OF EVIDENCE: Level 3 - Retrospective Cohort Study.

A Cadaveric Comparison of the Kinematic and Anatomical Axes and Arthrokinematics of the Metatarsosesamoidal and First Metatarsophalangeal Joints.

Presently, developments in weightbearing computed tomography and biplanar fluoroscopy technologies offer exciting avenues for investigating normative and pathologic foot function with increasing precision. Still, data quantifying sesamoid bone and proximal phalange motion are currently sparse. To express joint kinematics and compare various clinical cohorts, future studies of first ray motion will necessitate robust coordinate frames that respect the variations in underlying anatomy while also aligning closely with the functional, physiological axes of motion. These activity-dependent functional axes may be represented by a mean helical axis of the joint motion. Our cadaveric study quantified joint kinematics from weightbearing computed tomography scans during simulated toe lift and heel rise tasks. We compared the spatial orientations of the mean finite helical axes of the metatarsosesamoidal and metatarsophalangeal joints to the primary joint axis of two relevant methods for defining metatarsal coordinate frames: inertial axes and fitting of geometric primitives. The resultant kinematics exhibited less crosstalk when using a metatarsal coordinate system based on fitting cylindrical primitives to the bony anatomy compared to using principal component axes. Respective metatarsophalangeal and metatarsosesamoidal arthrokinematic contact paths and instantaneous centers of rotation were similar between activities and agree well with currently published data. This study outlines a methodology for quantitatively assessing the efficacy and utility of various anatomical joint coordinate system definitions. Improvements in our ability to characterize the shape and motion of foot bones in the context of functional tasks will elucidate their biomechanical roles and aid clinicians in refining treatment strategies.

A modified minimally invasive osteotomy for hallux valgus enables reduction of malpositioned sesamoid bones.

BACKGROUND: The current minimally invasive distal metatarsal osteotomy for hallux valgus (HV) is V-shaped, which prevents the correction of the rotational metatarsal head deformity and reduction of the sesamoid bones. We sought to determine the optimal method for sesamoid bone reduction during HV surgery. METHODS: We reviewed the medical records of 53 patients who underwent HV surgery between 2017 and 2019 using one of three techniques: open chevron osteotomy (n = 19), minimally invasive V-shaped osteotomy (n = 18), and a modified straight minimally invasive osteotomy (n = 16). The sesamoid position was graded using the Hardy and Clapham method on weight-bearing radiographs. RESULTS: When compared to open chevron and V-shaped osteotomies, the modified osteotomy resulted in significantly lower postoperative sesamoid position scores (3.74 ± 1.48, 4.61 ± 1.09, and 1.44 ± 0.81, respectively, P < 0.001). Furthermore, the mean change in postoperative sesamoid position score was greater (P < 0.001). CONCLUSION: The modified minimally invasive osteotomy was superior to the other two techniques in correcting HV deformity in all planes, including sesamoid reduction.

Alterations to the synovial invaginations of the navicular bone are associated with pathology of both the navicular apparatus and distal interphalangeal joint when evaluated using high field MRI.

Limited information exists regarding associations between distal interphalangeal joint (DIPJ) abnormalities and synovial invagination changes in the distal sesamoid (navicular) bone. This retrospective, analytical study aimed to measure specific characteristics of the synovial invaginations of the navicular bone to determine whether any single characteristic was associated with abnormalities in the DIPJ or navicular apparatus (NA) using high field MRI and a sample of 200 horses' feet. The DIPJ and NA were graded independently by three scorers. The grades were averaged, creating a global pathology score for the DIPJ, NA, and synovial invaginations. Higher global scores represented more severe pathology. The number of invaginations, depth of penetration, invagination shape, and cross-sectional area (CSA) of the largest invagination were recorded. Interobserver agreement was measured using Cohen's Kappa. Associations of global scores of the DIPJ and NA with individual invagination characteristics were assessed using linear mixed modeling. A significant relationship was found between the number of invaginations and global DIPJ score, with higher invagination numbers associated with higher DIPJ scores. For invagination depth and CSA, a significant relationship was noted with global scores of both the DIPJ and NA. Reliable relationships between the shape of synovial invaginations and global scores of DIPJ and NA were not found, likely due to poor interobserver scoring (0.305). These findings suggest that primary DIPJ disease and NA pathology should be considered when noticing alterations to navicular synovial invaginations on MRI. This contrasts traditional views that synovial invagination abnormalities are indicative solely of NA pathology.

Comparison of skeletal scintigraphy and standing 18 F-NaF positron emission tomography for imaging of the fetlock in 33 Thoroughbred racehorses.

This retrospective, methods comparison study aimed to compare skeletal scintigraphy and 18 F-NaF positron emission tomography (PET) for the detection of abnormalities in the fetlocks of Thoroughbred racehorses. Thirty-three horses (72 limbs) imaged with both scintigraphy and 18 F-NaF PET, for investigation of lameness or poor performance related to the fetlock, were included. Seven observers, including experienced racetrack practitioners, surgery and imaging residents, and a board-certified veterinary radiologist, independently reviewed all data for evidence of increased radiopharmaceutical uptake in 10 different regions of interest. The interobserver agreement was higher for PET (Kappa-weighted (K-w) 0.73 (0.51-0.84)) (median (range)) than for scintigraphy (0.61 (0.40-0.77)) (P < 0.0001). When scintigraphy and PET were compared, the agreement was fair (K-w 0.29). More sites of increased uptake were identified using PET compared with scintigraphy. Agreement between the two modalities was higher for the palmar/plantar metacarpal/metatarsal condylar regions (K-w 0.59) than for the proximal sesamoid bones (K-w 0.25). Increased radiopharmaceutical uptake was detected in the medial proximal sesamoid bone in 6.9% and 22.2% of limbs with scintigraphy and PET, respectively. The high interobserver agreement for PET, despite the recent introduction of this technique, demonstrates the ease of clinical interpretation of PET scans. The higher number of lesions detected with PET compared with scintigraphy can be explained by the higher spatial resolution and cross-sectional nature of this modality. Study findings supported using PET in a clinical population of racehorses, in particular for the assessment of the proximal sesamoid bones.

Correlations of Sesamoid Bone Subluxation with the Radiologic Measures of Hallux Valgus and Its Clinical Implications.

Background and Objectives: Hallux valgus is one of the most common chronic foot complaints, with prevalences of over 23% in adults and up to 35.7% in older adults. However, the prevalence is only 3.5% in adolescents. The pathological causes and pathophysiology of hallux valgus are well-known in various studies and reports. A change in the position of the sesamoid bone under the metatarsal bone of the first toe is known to be the cause of the initial pathophysiology. Purpose: The relationships between the changes in the location of the sesamoid bone and each radiologically measured angle and joint congruency in the hallux valgus remain as yet unknown. Therefore, this study investigated the relationships of sesamoid bone subluxation with the hallux valgus angle, intermetatarsal angle, and metatarsophalangeal joint congruency in hallux valgus patients. The goal is to know the hallux valgus angle, the intermetatarsal angle, and metatarsophalangeal joint congruency's correlation with hallux valgus severity and prognosis by revealing the relationship between each measured value and sesamoid bone subluxation. Materials and Methods: We reviewed 205 hallux valgus patients who underwent radiographic evaluation and subsequent hallux valgus correction surgery in our orthopedic clinic between March 2015 and February 2020. Sesamoid subluxation was assessed using a new five-grade scale on foot radiographs, and other radiologic measurements were assessed, such as hallux valgus angle, the intermetatarsal angle, distal metatarsal articular angle, joint congruency, etc. Conclusions: Measurements of the hallux valgus angle, interphalangeal angle, and joint congruency exhibited high interobserver and intraobserver reliabilities in this study. They also showed correlations with sesamoid subluxation grade.

Relationship between medial partite hallux sesamoid and hallux valgus in the general population.

BACKGROUND: An association between the medial partite hallux sesamoid (MPHS) and hallux valgus (HV) has been suggested; however, a causal relationship has not been confirmed. This study aimed to determine their causal relationship using a cross-sectional radiographic survey of a large-scale population cohort covering a wide age group. PATIENTS AND METHODS: The fifth survey of the Research on Osteoarthritis/Osteoporosis against Disability study involved 1997 participants aged 21-95 years who had undergone anteroposterior radiography of bilateral feet. The presence of MPHS, its morphology, and radiographic parameters related to the HV were assessed using radiographs. Changes in the prevalence of MPHS with age were assessed using trend tests. The relationship between the MPHS and HV was assessed based on sex and age. RESULTS: MPHS was found in 508 out of 3994 feet (12.7 %), with a significant difference in prevalence between men and women (10.0 % vs. 13.7 %, p < 0.001). Trend analysis demonstrated a significant decrease in MPHS occurrence with age in both sexes. HV angle was significantly higher in feet with MPHS than in those without (Men: 17.8 ± 7.0° vs. 14.0 ± 5.9°, p < 0.0001; Women: 19.6 ± 7.7° vs. 17.7 ± 7.9°, p < 0.0001). The prevalence of HV angle ≥ 20° was also significantly higher in feet with MPHS than in those without (Men: 33.3 % vs. 14.6 %, p < 0.0001; Women: 46.5 % vs. 34.6 %, p < 0.0001). This association between MPHS and HV was noticeable in younger adults and became less prominent with age. CONCLUSIONS: MPHS is associated with HV. The weakening of this relationship and the decreased prevalence of MPHS with age suggest that MPHS is not caused by HV, but is one of the causes of HV, especially in younger adults.

Change in the sub-sesamoid soft tissue thickness under different loading conditions.

[Purpose] To measure the sub-sesamoid soft tissue thickness change from non-loading to self-weight loading conditions. [Participants and Methods] The study included 17 female participants for the study. A questionnaire was used to collect the demographic data and participant anamnesis, such as the presence of foot injuries and diabetes. The measured height and weight were used to calculate the body mass index. Participants were required to stand on an evaluation device from non-loading to 100% loading conditions to measure the sub-sesamoid soft tissue thickness. [Results] Significant differences were observed between the tibial and fibular sub-sesamoid soft tissue thicknesses under non-loading and all loading conditions. Significant soft tissue thinning was observed with a change from non-loading to 25% loading condition. However, no significant differences in the rate of change were observed between the tibial and fibular sub-sesamoid soft tissue thicknesses at 100% loading. [Conclusion] The sub-fibular sesamoid soft tissue was thicker than the sub-tibial sesamoid soft tissue in all loading conditions. The sub-sesamoid soft tissue thickness change was larger during initial loading stage than during the late loading stage, which may be normal in healthy females in their 20s.

Common cellular origin and diverging developmental programs for different sesamoid bones.

Sesamoid bones are small auxiliary bones that form near joints and contribute to their stability and function. Thus far, providing a comprehensive developmental model or classification system for this highly diverse group of bones has been challenging. Here, we compare our previously reported mechanisms of patella development in the mouse with those of two anatomically different sesamoids, namely lateral fabella and digit sesamoids. We show that all three types of sesamoid bones originate from Sox9+ /Scx+ progenitors under the regulation of TGFß and independently of mechanical stimuli from muscles. Whereas BMP2 regulates the growth of all examined sesamoids, the differentiation of lateral fabella or digit sesamoids is regulated redundantly by BMP4 and BMP2. Next, we show that whereas patella and digit sesamoids initially form in juxtaposition to long bones, lateral fabella forms independently and at a distance. Finally, our evidence suggests that, unlike the synovial joint that separates patella from femur, digit sesamoids detach from the phalanx by formation of a fibrocartilaginous joint. These findings highlight both common and divergent molecular and mechanical features of sesamoid bone development, which underscores their evolutionary plasticity.

Radiographic and computed tomographic evaluation of supinator sesamoid bones in dogs.

BACKGROUND: The present study evaluated the frequency of supinator sesamoid bones (SSB) on radiography and computed tomography (CT). Interobserver agreement was evaluated in the detection of the SSBs in both methods. A correlation between the existence of SSBs and elbow diseases (ED) was assessed. For these purposes, radiographs, and CT scans of 100 dogs were scored by 3 observers. RESULTS: The SSB was identified as a round to oval-shaped opacity and measured 0.5-6.56 mm × 0.5-6.2 mm. SSBs were reported in an average of 8,33% of dogs on radiographs and 26% of dogs on CT; a bilateral sesamoid bone was present in 43,52% and 76,92% of these dogs, respectively. Seventy-two percent of the SSBs was identified on CT were not detected on radiographs. The Kappa test showed a substantial agreement (κ = 0.691) and a perfect agreement (κ = 1) between the observers in the detection of SSBs on radiography and on CT scans respectively. Additionally, a weak positive correlation was detected between ED and the existence of SSBs. CONCLUSION: A supinator sesamoid bone can be detected occasionally in the evaluation of the canine elbow joints by routine radiography. CT is superior to radiography for assessing SSBs with a higher interobserver agreement. The correlation of the existence of the SSBs and ED, needs further evaluations to prove a probable pathophysiological connection.

Origin of the avian predentary and evidence of a unique form of cranial kinesis in Cretaceous ornithuromorphs.

The avian predentary is a small skeletal structure located rostral to the paired dentaries found only in Mesozoic ornithuromorphs. The evolution and function of this enigmatic element is unknown. Skeletal tissues forming the predentary and the lower jaws in the basal ornithuromorph Yanornis martini are identified using computed-tomography, scanning electron microscopy, and histology. On the basis of these data, we propose hypotheses for the development, structure, and function of this element. The predentary is composed of trabecular bone. The convex caudal surface articulates with rostromedial concavities on the dentaries. These articular surfaces are covered by cartilage, which on the dentaries is divided into 3 discrete patches: 1 rostral articular cartilage and 2 symphyseal cartilages. The mechanobiology of avian cartilage suggests both compression and kinesis were present at the predentary-dentary joint, therefore suggesting a yet unknown form of avian cranial kinesis. Ontogenetic processes of skeletal formation occurring within extant taxa do not suggest the predentary originates within the dentaries, nor Meckel's cartilage. We hypothesize that the predentary is a biomechanically induced sesamoid that arose within the soft connective tissues located rostral to the dentaries. The mandibular canal hosting the alveolar nerve suggests that the dentary teeth and predentary of Yanornis were proprioceptive. This whole system may have increased foraging efficiency. The Mesozoic avian predentary apparently coevolved with an edentulous portion of the premaxilla, representing a unique kinetic morphotype that combined teeth with a small functional beak and persisted successfully for ∼60 million years.

Sesamoidectomy in Athletes: Outcomes From 2-Centers.

Sesamoid pain can arise from avascular necrosis, fracture, osteochondrosis, and advanced degeneration. Disorders of the sesamoids in athletes can be debilitating. Total sesamoidectomy of the involved sesamoid is considered an effective surgical treatment when conservative measures have failed. There is limited literature evaluating the outcome of sesamoidectomy in athletically active patients. Our 2-center study reports on 68 patients (70 procedures; 2 male patients were operated on both feet in separate procedures approximately 3 years apart; 41 (58.6%) tibial and 29 (41.4%) fibular sesamoidectomies; 24 males and 44 females, average age 28.4 ± 12.2 years) who underwent total sesamoidectomy from 01/2001 to 12/2019. In our cohort, the average time to return to activity (RTA) was 11.1 ± 5.1 weeks, with no statistically significant difference between gender and age, or between fibular and tibial sesamoidectomy in relation to RTA. There was a minimum follow-up of 1 year, with an average of 106.6 ± 66.6 months. The total incidence of complication rate was 5.7%. In athletes in whom conservative management has failed, sesamoidectomy is safe, and allows predictable return to their chosen sport. To our knowledge, none of the patients subsequently developed pathology to the remaining sesamoid.

The Effect of Hallux Valgus Surgery on the Transverse Plane Hallux Proximal Phalanx Position.

The objective of this investigation was to evaluate the apparent movement of the hallux proximal phalanx in the transverse plane relative to the second metatarsal following hallux valgus surgery. Pre- and postoperative radiographs of a consecutive series of 45 feet undergoing hallux valgus surgery were analyzed. Significant improvements were observed in the first intermetatarsal angle (12.4 vs 7.5 degrees; p < .001), hallux valgus angle (24.3 vs 13.4 degrees; p < .001), tibial sesamoid position (4.6 vs 2.7; p < .001), and second metatarsal-hallux proximal phalanx angle (80.1 vs 84.6 degrees; p < .001). No difference was observed in the distance between the second metatarsal bisection and the medial aspect of the tibial sesamoid (31.7 vs 31.5 mm; p = .756) nor between the second metatarsal bisection and medial aspect of the hallux proximal phalanx base (34.6 vs 34.2 mm; p = .592). Significant differences were observed between the second metatarsal bisection and the central aspect of hallux proximal phalanx base (26.5 vs 23.9 mm; p < .001) and between the second metatarsal bisection and the lateral aspect of the hallux proximal phalanx base (19.3 vs 15.4 mm; p < .001). A statistically significant difference was observed in the change of distance between the second metatarsal bisection and the medial, central, and lateral aspects of the hallux proximal phalanx base (-0.4 vs -2.6 vs -3.9 mm; p = .002). These results indicate that the hallux proximal phalanx does not translocate in the transverse plane following hallux valgus surgery, but instead pivots about the medial aspect of the joint.

Concentrated Bone Marrow Aspirate Injection for Hallux Sesamoid Disorders.

Concentrated bone marrow aspirate (CBMA) offers an alternative to sesamoid resection in end stage sesamoid pathology. CBMA potentiates the anti-inflammatory effect, stimulates local tissue regeneration and osteogenesis, when injected into bone. The purpose of this study is to evaluate the functional outcomes in a cohort of athletes following CBMA injection for the treatment of hallux sesamoid disorders. A retrospective case series of consecutive patients treated with CBMA injection for hallux sesamoid disorders were identified. Radiographs, Foot and Ankle Outcome Scores (FAOS), and Visual Analogue Scale (VAS) score were collected pre- and postinjections. Descriptive statistics were presented as the mean and standard deviation for continuous variables and frequency as percentages for categorical variables. Fifteen consecutive patients with were included with a mean follow-up time of 20.1 (range 12-34) months. Significant improvement in all scoring subscales of the FAOS and VAS score was noted preinjection compared to final follow-up postinjection (p < .001). Eight of 11 patients that were involved in sports prior to the CBMA injection returned to play, with 7 successfully returning to preinjury level status. Three patients required further treatment (20%). The case series suggests that CBMA injection is a safe and effective treatment option for hallux sesamoid disorders with a high rate of return to play.

Arthroscopic Sesamoidectomy for Hallux Sesamoid Disorders.

In this retrospective case series, we aimed to study arthroscopic sesamoidectomy, including surgical methods, clinical outcomes, and complications. We retrospectively reviewed the medical records of patients with hallux sesamoid disorders who underwent arthroscopic sesamoidectomy from July 2015 to July 2017. The visual analog scale for rating pain, Japanese Society for Surgery of the Foot scale scores, number of days taken to return to normal daily living, number of months taken to return to playing sports, and complications were analyzed. The mean follow-up duration was 3.2 years. Among 14 patients, there were 8 females and 6 males (median age: 39 years). The mean visual analog scale score improved from 75.4 to 14.3 mm; the mean Japanese Society for Surgery of the Foot score improved from 55.2 to 88.0 points. The mean time to return to activities of daily living was 5.3 days. Among the 5 patients who played sports, 3 and 2 patients resumed playing sports at 3 and 12 postoperative months, respectively. Complications included wound pain (n = 4), discomfort in severe weather (n = 4), numbness (n = 3), pain in the sole other than in the ball of the foot (n = 2), pain during hallux dorsiflexion (n = 2), residual sesamoid discomfort (n = 1), swelling (n = 1), toe-in gait (n = 1), and metatarsal head bone marrow edema (n = 1). Despite good clinical outcomes of arthroscopic sesamoidectomy, patients should be made aware of the many potential complications of this procedure prior to surgery.

Influence of sesamoid position after scarf osteotomy for hallux valgus on patient-reported outcome. A prospective cohor study.

BACKGROUND: The objective was to evaluate the influence of the postoperative sesamoid position as measured with conventional radiographs on the patient-reported outcome after scarf osteotomy. The hypothesis was that incomplete reduction of the sesamoid would result in a decreased functional outcome. METHODS: Eighty-two patients who underwent scarf osteotomy for hallux valgus were prospectively assessed for up to two postoperative years. The Self-Reported Foot and Ankle Score (SEFAS) was used to assess the quality of life, and the American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal Scale (AOFAS) for the functional outcome. A visual analogue scale (VAS) assessed pain, and Likert scale for patient satisfaction. Radiologically, hallux valgus angle (HVA), first-second intermetatarsal angle (IMA), and sesamoid position were analyzed. According to the final sesamoid position, patients were classified as normal position (48 patients) and outlier position (34 patients). A power analysis, conventional and logistic regression statistical analysis were performed. RESULTS: At the final follow-up, significant improvements in all clinical scores were observed for both groups (p = 0.001) with no significant difference in AOFAS score (p = 0.413), but SEFAS score (p = 0.023), VAS-pain (p = 0.006), and satisfaction (p = 0.014) were significantly better in the normal group than in the outlier group. There were significant differences between groups in final HVA (p = 0.042) and IMA (p = 0.040). In multivariate analysis, only lower VAS-pain score (OR 0.4, 95% CI 0.2-0.6; p = 0.039) and normal sesamoid position (OR 2.4, 95% CI 1.6-3.2; p = 0.012) were significant predictor of patient satisfaction. CONCLUSION: At two postoperative years, normal sesamoid position as measured on weight-bearing radiographs was associated with lower pain and better patient satisfaction in patients underwent scarf osteotomy for moderate to severe hallux valgus.