ZIC1 Dictates Osteogenesis Versus Adipogenesis in Human Mesenchymal Progenitor Cells Via a Hedgehog Dependent Mechanism.

Numerous intrinsic factors regulate mesenchymal progenitor commitment to a specific cell fate, such as osteogenic or adipogenic lineages. Identification and modulation of novel intrinsic regulatory factors represent an opportunity to harness the regenerative potential of mesenchymal progenitors. In the present study, the transcription factor (TF) ZIC1 was identified to be differentially expressed among adipose compared with skeletal-derived mesenchymal progenitor cells. We observed that ZIC1 overexpression in human mesenchymal progenitors promotes osteogenesis and prevents adipogenesis. ZIC1 knockdown demonstrated the converse effects on cell differentiation. ZIC1 misexpression was associated with altered Hedgehog signaling, and the Hedgehog antagonist cyclopamine reversed the osteo/adipogenic differentiation alterations associated with ZIC1 overexpression. Finally, human mesenchymal progenitor cells with or without ZIC1 overexpression were implanted in an ossicle assay in NOD-SCID gamma mice. ZIC1 overexpression led to significantly increased ossicle formation in comparison to the control, as assessed by radiographic and histologic measures. Together, these data suggest that ZIC1 represents a TF at the center of osteo/adipogenic cell fate determinations-findings that have relevance in the fields of stem cell biology and therapeutic regenerative medicine.

Clinical application of high-resolution spiral CT scanning in the diagnosis of auriculotemporal and ossicle.

Precision and intelligence in evaluating the complexities of middle ear structures are required to diagnose auriculotemporal and ossicle-related diseases within otolaryngology. Due to the complexity of the anatomical details and the varied etiologies of illnesses such as trauma, chronic otitis media, and congenital anomalies, traditional diagnostic procedures may not yield accurate diagnoses. This research intends to enhance the diagnosis of diseases of the auriculotemporal region and ossicles by combining High-Resolution Spiral Computed Tomography (HRSCT) scanning with Deep Learning Techniques (DLT). This study employs a deep learning method, Convolutional Neural Network-UNet (CNN-UNet), to extract sub-pixel information from medical photos. This method equips doctors and researchers with cutting-edge resources, leading to groundbreaking discoveries and better patient healthcare. The research effort is the interaction between the CNN-UNet model and high-resolution Computed Tomography (CT) scans, automating activities including ossicle segmentation, fracture detection, and disruption cause classification, accelerating the diagnostic process and increasing clinical decision-making. The suggested HRSCT-DLT model represents the integration of high-resolution spiral CT scans with the CNN-UNet model, which has been fine-tuned to address the nuances of auriculotemporal and ossicular diseases. This novel combination improves diagnostic efficiency and our overall understanding of these intricate diseases. The results of this study highlight the promise of combining high-resolution CT scanning with the CNN-UNet model in otolaryngology, paving the way for more accurate diagnosis and more individualized treatment plans for patients experiencing auriculotemporal and ossicle-related disruptions.

Bone cement repair of malleus handle fractures: Intraoperative video and case report of two patients.

Isolated malleus fractures are a rare occurrence with few reported cases in the literature. Symptoms include sudden otalgia, hearing loss, tinnitus and aural fullness. Work-up and diagnosis are based on a combination of thorough anamnesis and careful otoscopic evaluation or high-resolution computer tomography. We present two cases of isolated malleus handle fractures who were diagnosed based on a combination of pneumatic otoscopy and tympanometry. Both fractures were surgically repaired using hydroxyapatite bone cement as showcased in the supplemental video material. Post-operative audiometry showed improvement in the pure-tone-average of both patients as well as normalisation of tympanometry. Isolated malleus fracture should be suspected in cases of sudden hearing loss and tinnitus following digital manipulation of the outer ear canal together with a conductive hearing loss with a mostly high-frequent air-bone-gap and hypercompliant tympanometry with hypermobility of the tympanic membrane on pneumatic insufflation. Surgical repair of the fracture using bone cement has good hearing outcomes and leads to improvement in auditory symptoms.

Morphobiometry of the scleral ossicle rings in Chelonia mydas sea turtles.

OBJECTIVE: Scleral ossicle rings of reptiles have endoskeletal functions that are not completely understood. Moreover, descriptive reports on the anatomy of those rings are scarce. We tried to make an anatomical description that could contribute to a better understanding of their functions. ANIMAL STUDIED AND PROCEDURES: We quantified, histologically characterized and evaluated the morphobiometry of the scleral ossicles, and measured the aditus orbitae of 25 sea turtle (Chelonia mydas) heads. RESULTS: The aditus orbitae represented about one-third of the total head length and the mean area of the internal opening of each ring was up to 8.37% of the aditus orbitae area. The mean internal diameter of the rings (6.32 mm) was characteristic of scotopic species and the most frequent number of ossicles per ring varied between 11 and 12. Two new classifications were proposed for the ossicle types: plus-Verzahnung (+V) and minus-Verzahnung (-V). The bone tissue revealed a lamellar arrangement typical of compact and resistant bones. CONCLUSION: The obtained data may be used to support and expand the understanding of functions, animal activity patterns, distinctions between taxa and taphonomic interpretations.

Male elite soccer players have a higher incidence of accessory ossicles in the foot and ankle.

PURPOSE: Accessory ossicles are caused by the failure of the fusion of secondary ossification centres and are more likely to occur due to heavy loading during the growth period or improper treatment after injury. This study aimed to investigate the incidence of foot and ankle accessory ossicles in male professional soccer players. METHODS: This study included male professional soccer players who underwent medical checkups at our hospital between 2017 and 2023 as the soccer group. Medical checkups included radiographs of bilateral anteroposterior and oblique foot, as well as bilateral anteroposterior and lateral ankle. Male patients age-matched with the soccer group who visited our hospital undergoing anteroposterior and oblique foot or anteroposterior and lateral ankle radiography were included in the control group. The incidence of accessory ossicles was investigated and compared between the soccer and control groups. RESULTS: In this study, 276 ankles and 276 feet, as well as 121 ankles and 79 feet, were included in the soccer and control groups, respectively. The incidence of accessory ossicles in the soccer and control groups was as follows: accessory navicular 35.9%, 24% (P = .049), os peroneum 8.0%, 2.5% (P = .09); os supranaviculare 7.6%, 1.3% (P = .039); os infranaviculare 1.4%, 1.3% (P = .090); os calcaneus secundarius 4.3%, 0% (P = .059); os vesalianum 0%, 0%; os subfiblare 12.7%, 2.5% (P < .001); os subtibiale 18.1%, 2.5% (P = .001); and os trigonum 89%, 24% (P < .001). CONCLUSIONS: Male professional soccer players had a higher incidence of accessory navicular, os supranaviculare, os subfiblare, os subtibiale, and os trigonum.

Os supratrochleare anterius: a very rare clinical case and review of literature.

PURPOSE: The accessory bones around the elbow are very rare variant structures, present in approximately 0.7% of cases. They can cause diagnostic problems and can be mistaken for pathological structures, especially when pain and limitation of elbow movements are present and a trauma can be traced in the patient's history. They are of different nature, either presenting within muscle tendons as sesamoids (brachialis and triceps brachii muscles) or presenting intra-articularly probably as separated or accessory ossification centres. The least common is the os supratrochleare anterius. METHODS: We present a case of a young male, featuring chronic blocking and 20° limited flexion of his right elbow, which bothered him during his occupation as a locksmith. In history, he suffered minor trauma to the elbow 20 years ago. X-ray and CT showed a large ossicle in the coronoid fossa of the humerus. RESULTS: The ossicle was surgically extracted in small pieces. The patient left satisfied with no mention of complaints. CONCLUSION: The os supratrochleare anterius is a very rare accessory bone of the elbow, located in the coronoid fossa of the humerus which can mimic many pathological states, and limit movements and causing pain around the elbow.

The prevalence and anatomy of accessory navicular bone: a meta-analysis.

PURPOSE: There have been over 40 descriptions of the common developmental variants of the accessory ossicles of the feet. Although predominantly asymptomatic, they sometimes may be linked to painful conditions. One of the most common accessory ossicles in the foot is the accessory navicular bone (AN), located on the medial side of the foot. Our research provides a first meta-analysis on this topic that establishes its frequency by contrasting 39 studies from across the globe. METHODS: Up to February 2024, PubMed and Embase databases were thoroughly searched for research on the AN. Eligible data regarding AN prevalence was extracted. This study strictly adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: A total of 39 studies, 11,015 patients, and 36,837 feet were analyzed in our study. The pooled prevalence estimate (PPE) of AN was found to be 17.5% (95%CI: 11.5-25.7) and 12.6% (95%CI: 10.1-15.5) in patients and feet analyses, respectively. Accessory navicular occurred bilaterally in 50.0% of patients, with similar distribution in gender-based groups (21.1% of males and 22.0% of females were confirmed with AN). Accessory navicular was most prevalent in the East Asian population (38.4%) and least prevalent in North Americans (8.0%). No significant differences in AN prevalence were found when comparing different imaging modalities (X-ray and cadaver dissection). CONCLUSION: Accessory navicular is a common finding in imaging studies. Its prevalence depends on the population covered by the study but is not affected by the patient's gender or the imaging modality utilized for AN assessment.

High-throughput segmentation, data visualization, and analysis of sea star skeletal networks.

The remarkably complex skeletal systems of the sea stars (Echinodermata, Asteroidea), consisting of hundreds to thousands of individual elements (ossicles), have intrigued investigators for more than 150 years. While the general features and structural diversity of isolated asteroid ossicles have been well documented in the literature, the task of mapping the spatial organization of these constituent skeletal elements in a whole-animal context represents an incredibly laborious process, and as such, has remained largely unexplored. To address this unmet need, particularly in the context of understanding structure-function relationships in these complex skeletal systems, we present an integrated approach that combines micro-computed tomography, automated ossicle segmentation, data visualization tools, and the production of additively manufactured tangible models to reveal biologically relevant structural data that can be rapidly analyzed in an intuitive manner. In the present study, we demonstrate this high-throughput workflow by segmenting and analyzing entire skeletal systems of the giant knobby star, Pisaster giganteus, at four different stages of growth. The in-depth analysis, presented herein, provides a fundamental understanding of the three-dimensional skeletal architecture of the sea star body wall, the process of skeletal maturation during growth, and the relationship between skeletal organization and morphological characteristics of individual ossicles. The widespread implementation of this approach for investigating other species, subspecies, and growth series has the potential to fundamentally improve our understanding of asteroid skeletal architecture and biodiversity in relation to mobility, feeding habits, and environmental specialization in this fascinating group of echinoderms.

Unilateral accessory scapular ossicle with sprengel deformity in a trauma patient: A case report.

Herein we present a rare anatomic variation of unilateral accessory scapular ossicle in a trauma patient and its rare association with a common scapular anomaly, Sprengel deformity. Foci that appear near the inferior angle of the scapula due to failure of bony fusion during bone maturation are called accessory scapular ossicles. Sprengel deformity is defined as the congenitally high position of the scapula. The recognition of the normal variants of scapula is important, since they could be confused with other pathologies, such as fracture and pulmonary nodule in a trauma patient. Therefore, radiologists should be familiar to these entities even rarely seen.

Is the Small Ossicle of Type 1 Accessory Navicular a Cause of Foot Pain?-A Case Report.

Background and objectives: An accessory navicular (AN) bone is often classified into types 1-3 according to the Veitch classification, and symptomatic type 1 patients usually receive non-surgical treatment. However, there are cases in which AN cannot be classified into one of these three types using this classification system, and the small ossicle of type 1 AN may not be the cause of foot pain. This report aimed to present a case of symptomatic type 1 AN that required surgical treatment without the excision of the small ossicle after long-term conservative treatment had failed. Case presentation: A 15-year-old girl who was diagnosed with symptomatic type 1 AN was referred to our department. Medial-side foot pain had prevented her from playing soccer well. She had been treated conservatively for type 1 AN for more than 12 months at several orthopedic clinics. Tenderness of the prominent navicular tubercle was identified, and computed tomography and magnetic resonance imaging findings suggested that the cause of her foot pain was derived from the prominent navicular tubercle not the small ossicle itself. Osteotomy of the prominent navicular tubercle with the advancement of the tibialis posterior tendon, without excision of the ossicle, was performed. At the 12-month follow-up examination, she was completely free from foot pain, and the patient-reported outcome measures were excellent. She now plays soccer at the pre-injury level. Conclusions: We report the case of a patient with symptomatic type 1 AN who underwent osteotomy of the prominent navicular tubercle with advancement of the tibialis posterior tendon, without excision of the ossicle, and who showed favorable short-term clinical outcomes. The evaluation of symptomatic patients with AN based on the Veitch classification alone may lead to inappropriate management. The small ossicle of type 1 AN was not the cause of foot pain in the present case.

Diagnosis, imaging, and potential morbidities of the hallux interphalangeal joint os interphalangeus.

Hallux pain is a common entity with a differential diagnoses including hallux valgus, hallux limitus/rigidus, and gout and specifically at the interphalangeal joint (IPJ), flexor hallucis longus (FHL) tenosynovitis, and joint arthrosis. An under-recognized source of pain is the os interphalangeus, an ossicle typically located at the plantar aspect of the hallucal interphalangeal joint. This ossicle is radiographically visible in its ossified form in 2-13% of individuals, but can also be present as an ossified or non-ossified nodule in patients. The os interphalangeus may be centrally or eccentrically located, and although originally believed to be a sesamoid bone in the FHL tendon, it is an ossicle located in the joint capsule of the IPJ and separated from the tendon by a bursa. When the ossicle is absent, the bursa is also absent and the tendon is attached to the joint capsule. Infrequently, the os may be located eccentrically under the first IPJ and reflect persistence of one of the distal phalanx. Rarely, the os interphalangeus may be dorsal to the IPJ. The os interphalangeus is best evaluated on radiographs, ultrasound, and MRI. Pain is a result of altered mechanics with arthrosis or frictional effects with bursitis, tenosynovitis, or intractable plantar keratosis (IPK). The ossicle may also displace into a dislocated IPJ, preventing reduction. The os interphalangeus may be centrally or eccentrically located, and although originally believed to be a sesamoid bone. This has been found within the plantar joint capsule of the distal hallucal interphalangeal joint and separated from the tendon by a bursa. Uncommonly, the location may be plantar eccentric and reflect persistence of one of the ossification centers of the distal phalanx. Although the ossicle can be imaged with standard AP and lateral radiographs in many cases, in those cases of unexplained pain with no radiographically visible ossicle, and the presence of friction blisters, intractable plantar keratosis (IPK), hyper-extension of the IPJ, hallux limitus/rigidus, or metatarsophalangeal joint (MTPJ) arthrodesis, an MRI or CT should be considered to identify a non-ossified fibrocartilaginous node. This is of particular concern in a patient with a history of underling diabetes mellitus or other metabolic disorders associated with diminished pedal sensation where neurotrophic changes place them most at risk for complications associated with excessive plantar pressure. Pain is a result of altered biomechanics with arthrosis, or frictional effects causing bursitis, tenosynovitis, or IPK. The ossicle may also displace into a dislocated IPJ, preventing reduction. In this article, we will describe the anatomy and imaging appearance of the common os interphalangeus variants and associated complications including frictional effects, arthrosis, and IPK and discuss conservative and surgical management of a symptomatic ossicle.

A rare cause of foot pain in an adolescent due to os paracuneiforme: a case report and review of the literature.

Os paracuneiforme is an extremely rare accessory ossicle located at the medial aspect of the medial cuneiform bone. Although foot pain secondary to accessory ossicles is well known, symptomatic os paracuneiforme that requires surgical excision is rarely reported in the current literature. Herein, a 12-year-old boy with symptomatic os paracuneiforme is presented, and its clinical and imaging findings as well as the treatment are discussed.

Diagnostic and therapeutic approach to meniscal ossification: a systematic review.

PURPOSE: The purpose of this study was to systematically review case reports and case series about meniscal ossicle, to summarize existing evidence. Specifically, to identify the etiology, demographic characteristics, localization, clinical features, diagnostic procedures and treatment options of this rare entity. Although, case reports/ series are of low level of evidence, a systematic review of such studies can provide and help us to gain a better understanding and awareness of meniscal ossicle. METHODS: Two authors searched three online databases (MEDLINE, SCOPUS and GOOGLE SCHOLAR) from inception until March 2020 for the literature on meniscal ossicle. Inclusion criteria included case series, case reports and case-based reviews, available in full-text version, in English and that concern humans. Reports published in languages other than English were excluded, as well as articles with no electronic full text availability. Case reports using the term "meniscal ossicle" to describe an acute avulsion fracture of the tibial root of the meniscus, were also excluded. RESULTS: Of 453 initial studies, 38 studies satisfied inclusion criteria. In total 169 patients were included of whom 107 (63%) were males and 62 (37%) were females. Mean age was 44 years (range 12-87). According to Magnetic resonance imaging findings, in 144 knees (86%) the ossicle was localized at the posterior root or horn of the medial meniscus. 60% of the patients had a history of trauma. The predominant symptom in 87% of patients was knee pain. In all patients was detected an intra-articular density structure in computed radiography. 76% had associated meniscal tear, 61% had intraarticular cartilage loss, 34% meniscal extrusion and 28% anterior cruciate ligament injury. Treatment modalities included conservative regimen in 40 patients, while 59 patients underwent surgical excision. CONCLUSION: The most possible etiology of meniscal ossicle is posttraumatic heterotopic ossification and small occult bony avulsion fracture. It is commonly observed in individuals complaining about knee pain with history of antecedent trauma. The presence of a meniscal ossicle should alert the physician to the high likelihood of the patient having an associated meniscal tear, articular cartilage loss, ACL injury or meniscal extrusion. Along with the meniscal ossicle, the associated meniscal tear should be treated as well.

CXCL12 is required for stirrup-shaped stapes formation during mammalian middle ear development.

BACKGROUND: The mammalian middle ear comprises a chain of three ossicles-the malleus, incus, and stapes-each of which has a unique morphology for efficiently transmitting sound information. In particular, the stapes, which is attached to the inner ear, is stirrup-shaped with a head and base connected by two crural arches, forming the stapedial foramen, through which the stapedial artery passes. However, how the stapes acquires this critical stirrup shape for association with the stapedial artery during development is not clear. RESULTS: C-X-C motif chemokine ligand 12 (CXCL12) is a chemoattractant essential for cellular movement and angiogenesis. In Cxcl12 -/- embryos, migration of neural crest cells into the prospective middle ear regions and their mesenchymal condensation to form the three ossicles proceed normally in correct alignment with each other and the inner ear. However, in the absence of CXCL12, the stapes loses its stirrup shape and instead exhibits a columnar shape lacking the crural arches and central hole. In addition, although the stapedial artery initially forms during early mesenchymal condensation of the stapes, it degenerates without CXCL12 function. CONCLUSION: CXCL12 plays an essential role in establishing the stirrup-shaped architecture of the stapes, possibly by maintaining the stapedial foramen and stapedial artery throughout development.

Uncovering the secreted signals and transcription factors regulating the development of mammalian middle ear ossicles.

The mammalian middle ear comprises a chain of ossicles, the malleus, incus, and stapes that act as an impedance matching device during the transmission of sound from the tympanic membrane to the inner ear. These ossicles are derived from cranial neural crest cells that undergo endochondral ossification and subsequently differentiate into their final functional forms. Defects that occur during middle ear development can result in conductive hearing loss. In this review, we summarize studies describing the crucial roles played by signaling molecules such as sonic hedgehog, bone morphogenetic proteins, fibroblast growth factors, notch ligands, and chemokines during the differentiation of neural crest into the middle ear ossicles. In addition to these cell-extrinsic signals, we also discuss studies on the function of transcription factor genes such as Foxi3, Tbx1, Bapx1, Pou3f4, and Gsc in regulating the development and morphology of the middle ear ossicles.

Unilateral, Volume-expanding Os Subcalcis: Patient History and Treatment: A Case Report.

Accessory bones of the foot are common, but the presence of accessory bones located at the plantar aspect of the calcaneus is rare. We present the case of a 72-year-old female that suffered with a volume expanding os subcalcis. Due to marked disability, the large os subcalcis was excised with a favorable outcome.

Accessory Ossicles in the Region of the Foot and Ankle: An Epidemiologic Survey in a Jordanian Population.

Background and Objectives: The incidence of accessory bones in the region of foot and ankle is quite variable between studies and are often confused with avulsion fractures in trauma patients with musculoskeletal injuries. The aim of this study was to assess the incidence of accessory ossicles of the foot and ankle according to gender, side and coexistence, and to determine how frequently accessory ossicles were misdiagnosed as avulsion fractures. Materials and Methods: Oblique and/or lateral foot radiographs of 1000 adult patients referred from emergency departments to foot and ankle clinic were retrospectively reviewed for the presence of accessory ossicles. The Kappa statistic was used in order to assess the validity of radiographic interpretation for the presence of these bones. Results: Accessory ossicles were detected in 40.2% of the radiographs. The incidence rates for the accessory ossicles in order of frequency were: Os trigonum (15.4%), accessory navicular (13.7%), os peroneum (11.5%), os vesalianum (1.1%), os supranaviculare (0.7%), os subfibulare (0.6%), os talotibiale (0.4%), os calcaneus secundarius (0.3%), os supratalare (0.3%), os infranaviculare (0.3%), os intermetatarseum (0.2%), and os subtibiale (0.1%). Coexistence of two or three ossicles in the same foot was observed in 4.4% of the cases, mostly coexistence with os peroneum (2.9%), followed by accessory navicular (1.6%). 2.7% of accessory ossicles were initially misdiagnosed as avulsion fractures at emergency departments. Interrater agreement over identification of different accessory ossicles was found to be reasonably reliable, with a Kappa greater than 0.80 for all assessed bones. Conclusions: In clinical practice, a thorough knowledge of normal anatomical variants is essential to facilitate appropriate diagnosis and treatment and can help to prevent diagnostic errors.

Outcomes of ossicle resection and anatomic reconstruction of lateral ligaments for chronic ankle instability with large malleolar accessory ossicles.

BACKGROUND: Malleolar accessory ossicles can be found in patients with chronic lateral ankle instability (CLAI). Ossicle resection combined with the modified Broström procedure is the most commonly used surgical method. However, an unrepairable gap after ossicle resection often occurs in patients with large ossicles. PURPOSE: This study analysed the clinical outcomes of ossicle resection and anatomic ligament reconstruction (ALR) for CLAI with large malleolar accessory ossicles. METHODS: This study was a retrospective case series. Since 2014, we have adopted ALR for patients with difficulties using the modified Broström procedure after ossicle resection. Sixteen patients with chronic ankle instability and malleolar accessory ossicles were treated with this method between December 2014 and February 2018. The average age of the patients at the time of surgery was 28.9 (range, 16-65) years. They were followed up for an average time of 26.9 (range, 12-47) months. The clinical outcomes were evaluated using the Visual Analogue Scale, Karlsson-Peterson ankle scoring system, subjective satisfaction of patients, and radiographic parameters. RESULTS: All unrepairable cases occurred in patients with ossicles larger than or equal to 10 mm. The VAS score improved from 3.5 ± 1.6 preoperatively to 1.4 ± 1.0 at the final follow-up (p < 0.05), and the Karlsson-Peterson score improved significantly from 52.7 ± 15.1 to 86.4 ± 8.2 (p < 0.05). There was also an obvious change in the varus talar tilt angle (15.4 ± 2.0° vs 6.2 ± 1.6°, p < 0.05) and anterior talar displacement (14.3 ± 2.1 mm vs 6.3 ± 1.4 mm, p < 0.05). Fourteen patients (87.5%) were satisfied (excellent or good) with their clinical outcomes. CONCLUSION: If modified Broström procedure is difficult to accomplish effectively after ossicle resection for chronic ankle instability with large malleolar accessory ossicles, ALR is a viable option with satisfactory clinical results.

Diagnosis of avulsion fractures of the distal fibula after lateral ankle sprain in children: a diagnostic accuracy study comparing ultrasonography with radiography.

BACKGROUND: The purpose of this study was to determine the diagnostic accuracy of ultrasonography for the diagnosis of avulsion fractures of the distal fibula for lateral ankle sprain in children and compare it to that of radiography. METHODS: Children who sustained lateral ankle sprain were prospectively surveyed. They underwent both ultrasonography and radiography at the first clinic visit to diagnose any concomitant avulsion fractures of the distal fibula. The patients underwent follow-up radiography 4 weeks later to obtain the reference standard diagnosis. The measures of diagnostic accuracy (i.e., sensitivity, specificity, positive predictive value, and negative predictive value) of the initial ultrasonography and radiography were calculated; they were then compared using the McNemar test. Totally, 52 patients (with a median age of 9 years) were analyzed. RESULTS: On the reference standard (follow-up) radiographs, 32 patients (62%) were found to have avulsion fractures of the distal fibula. The sensitivity, specificity, positive predictive value, and negative predictive value for ultrasonography were 94, 85, 91, and 89% respectively; and 81, 100, 100, and 77% respectively for radiography at the first visit. There were no significant differences in sensitivity and specificity between the two diagnostic methods (P = 0.22, 0.25). CONCLUSIONS: Ultrasonography has a high diagnostic accuracy, which is comparable to that of radiography, for the diagnosis of avulsion fracture of the distal fibula. Ultrasonography may be used as an option of imaging modality for lateral ankle sprain in children.

Simultaneous ossicle resection and lateral ligament repair give excellent clinical results with an early return to physical activity in pediatric and adolescent patients with chronic lateral ankle instability and os subfibulare.

PURPOSE: To elucidate surgical outcomes in pediatric/adolescent patients with chronic lateral ankle instability and os subfibulare. METHODS: A retrospective chart review was conducted of pediatric/adolescent patients with chronic lateral ankle instability and os subfibulare following simultaneous ossicle resection and lateral ligament repair using suture anchors with subsequent immediate full weightbearing and active range of motion exercises for the ankle in our department between 2013 and 2017. Clinical outcomes were evaluated by comparing preoperative and final follow-up American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS) and Karlsson-Peterson ankle function scores. Intervals between surgery and return to physical education in school were determined. RESULTS: 31 feet of 15 male and 16 female patients were examined. Mean postoperative follow-up duration was 40.7 ± 12.7 (range 24-66) months. Mean AOFAS score increased significantly from 66.3 ± 2.5 (range 62-77) preoperatively to 96.5 ± 4.9 (range 87-100) at final follow-up (p < 0.001). Mean Karlsson-Peterson score increased significantly from 51.7 ± 4.0 (range 47-70) preoperatively to 95.3 ± 6.7 (range 80-100) at final follow-up (p < 0.001). Mean interval between surgery and return to physical education in school was 11.4 ± 1.6 (range 10-18) weeks. CONCLUSION: Simultaneous ossicle resection and lateral ligament repair using suture anchors with subsequent immediate full weightbearing and active ankle range of motion exercises may give excellent clinical outcomes with early return to physical activity for chronic lateral ankle instability with os subfibulare in pediatric/adolescent patients desiring an early return to physical activity. Level of evidence III.