Predictors of flatfoot in 11-12-year olds: a longitudinal cohort study.

BACKGROUND: The structures around the navicular bones, which constitute the medial longitudinal arch, develop by 10 years of age. While navicular bone height is often emphasized in the assessment of flatfoot, three-dimensional (3D) evaluations, including those of structural parameters during inversion, have rarely been investigated. If the development of flatfoot during the growth process could be predicted, appropriate interventions could be implemented. Therefore, in this longitudinal cohort study, we developed a system, utilizing smartphones, to measure the 3D structure of the foot, performed a longitudinal analysis of changes in midfoot structures in 124 children aged 9-12 years, and identified factors influencing the height of the navicular bone. The foot skeletal structure was measured using a 3D system. RESULTS: Over 2 years, foot length and instep height increased during development, while navicular height decreased. The 25th percentile of the instep height ratio and navicular height ratio at ages 9-10 years did not exceed those at ages 11-12 years, with percentages of 17.9% and 71.6%, respectively, for boys, and 15.8% and 49.1%, respectively, for girls. As the quartiles of the second toe-heel-navicular angle (SHN angle) increased at ages 9-10 years, the axis of the bone distance (ABD) and SHN angles at ages 11-12 years also increased, resulting in a decrease in the navicular height ratio. A significant inverse correlation was found between changes in SHN angle and navicular height ratio. These findings indicate that the navicular bone rotation of the midfoot is a predictor of the descent of the navicular bone. CONCLUSIONS: This study revealed that some children exhibit decreases in navicular bone height with growth. As a distinct feature, the inversion of the navicular bone promotes flattening of the midfoot. Thus, this study provides insights into changes in midfoot development in children and provides an effective evaluation index.

Clinical Effects of Tibial Posterior Tendon Reconstruction in the Treatment of Young Athletes With Accessory Navicular Bone Syndrome.

OBJECTIVE: To compare the effects of anchor reconstruction of posterior tibial tendon with the traditional Kidner's procedure for accessory navicular bone syndrome. METHODS: A retrospective analysis was conducted on 40 young athletes diagnosed with accessory navicular bone syndrome who were admitted to our hospital from 2018 to 2021. Among them, 20 patients underwent the modified Kidner procedure for the anchor reconstruction of the posterior tibial tendon (Experimental group), while the remaining 20 patients were treated with the traditional Kidner's procedure (Control group). Regular follow-ups were conducted to evaluate the degree of relief of foot symptoms and functional recovery. RESULTS: All patients were followed up for 12 to 24 months (mean duration: 18.6±3.7) after the operation. At the last follow-up, significant differences were observed in the function and symptom relief of the affected foot compared to the preoperative state. The experimental group had a mean operation time of 52.10 ± 3.41 minutes, significantly shorter than the control group's 61.25 ± 2.75 minutes. The mean time to return to normal activity was 12.65 ± 1.23 weeks for the experimental group, compared to 15.25 ± 1.16 weeks for the control group. CONCLUSION: The modified Kidner procedure demonstrates a higher patient satisfaction rate compared to the traditional Kidner procedure. This is attributed to its shorter duration, reduced trauma, and quicker recovery of normal activity.

Osteochondrosis in the central and third tarsal bones of young horses.

Recently, the central and third tarsal bones of 23 equine fetuses and foals were examined using micro-computed tomography. Radiological changes, including incomplete ossification and focal ossification defects interpreted as osteochondrosis, were detected in 16 of 23 cases. The geometry of the osteochondrosis defects suggested they were the result of vascular failure, but this requires histological confirmation. The study aim was to examine central and third tarsal bones from the 16 cases and to describe the tissues present, cartilage canals, and lesions, including suspected osteochondrosis lesions. Cases included 9 males and 7 females from 0 to 150 days of age, comprising 11 Icelandic horses, 2 standardbred horses, 2 warmblood riding horses, and 1 coldblooded trotting horse. Until 4 days of age, all aspects of the bones were covered by growth cartilage, but from 105 days, the dorsal and plantar aspects were covered by fibrous tissue undergoing intramembranous ossification. Cartilage canal vessels gradually decreased but were present in most cases up to 122 days and were absent in the next available case at 150 days. Radiological osteochondrosis defects were confirmed in histological sections from 3 cases and consisted of necrotic vessels surrounded by ischemic chondronecrosis (articular osteochondrosis) and areas of retained, morphologically viable hypertrophic chondrocytes (physeal osteochondrosis). The central and third tarsal bones formed by both endochondral and intramembranous ossification. The blood supply to the growth cartilage of the central and third tarsal bones regressed between 122 and 150 days of age. Radiological osteochondrosis defects represented vascular failure, with chondrocyte necrosis and retention, or a combination of articular and physeal osteochondrosis.

Computed tomography and fluoroscopy versus radiographic guidance for internal fixation of simulated dorsomedial-plantarolateral central tarsal bone fractures in nonracehorses.

OBJECTIVE: The aim of this study was to assess screw placement in simulated dorsomedial-plantarolateral central tarsal bone (CTB) fractures using two imaging guidance techniques - computed tomography (CT) with fluoroscopy compared to digital radiography alone (DR). STUDY DESIGN: Experimental study. SAMPLE POPULATION: Equine cadaver hindlimbs (n = 10 pairs). METHODS: One tarsus per pair was randomly assigned to have a 4.5 mm cortical screw placed across the CTB using CT and fluoroscopy (CT/F group) or digital radiography alone (DR group). Postoperative CT was performed on all limbs. Variables related to marker placement, procedure time, and screw positioning were recorded and compared using a paired t-test for dependent means (p < .05). RESULTS: Time for marker placement was longer for the CT/F group (p = .001), with no difference in total procedure time (p = .12). CT/F was not superior to radiography alone (p > .05) for parameters related to screw positioning. Based on the 95% CI, there was greater range in relative screw length using radiography (76.5%-91.2%) versus CT/F (78.4%-84.0%). CONCLUSION: Internal fixation of CTB fractures can be successfully performed using either technique for imaging guidance. CT and fluoroscopy did not result in faster or more accurate screw placement compared to radiographs alone, except in determining screw length. CLINICAL SIGNIFICANCE: Mild adjustments in fluoroscopic or radiographic angle appeared to be a point of variability in the perception of screw placement. While CT is recommended for improved understanding of fracture configuration and surgical planning, radiographic guidance may be a suitable alternative for internal fixation of dorsomedial-plantarolateral fractures.

Morphological measurements and classification of the navicular bone: a study based on computed tomography imaging.

OBJECTIVE: The purpose of this study was to present the classification of navicular bones and the anatomical basis for the diagnosis and treatment of navicular fractures of the foot. METHOD: 351 computed tomographic (CT) images of the navicular bone were analyzed and classified. The navicular bone's anatomical morphology was measured by three independent researchers in each type. Analysis and recording of the measurement results followed. RESULT: Navicular bones were assorted into three types: I shape(37.04%), II shape(54.41%), and III shape(8.55%). The left and right sides did not differ in any appreciable ways, except ab, bc, and ∠abc (P < 0.05); And all data were statistically different between men and women except for ∠abc (p > 0.05). CONCLUSION: The classification of the navicular bone in this study may be helpful in making the treatment decision for navicular fracture. LEVEL OF CLINICAL EVIDENCE: 4.

Outcomes of Selective Arthrodesis Based on Joints Affected in 33 Feet With Müller-Weiss Disease.

No consensus exists regarding operative treatment of Müller-Weiss disease (MWD). Its only classification is based solely on Méary's angle and serves neither as guide to management nor prognosis. We report on 33 feet that underwent surgery following failed conservative management. Treatment was directed towards joint(s) involved, as determined by clinical examination, plain radiography and SPECT-CT. Thus, surgery consisted of isolated talonavicular in 6 feet, triple in 8, subtalar and talonavicular in 7, talonaviculocuneiform in 4, talonaviculocuneiform with interpositional tricortical iliac crest graft in 6 and pantalar arthrodesis in 2. PROMIS scores for pain interference and depression decreased significantly (p < .001) with significant accompanying increase in physical function (p = .003). Union occurred in 31 of 33 feet (94%) with complete resolution of pain at an average follow-up of 84 months. Of the 2 nonunions, 1 had fracture through the lateral navicular, and the other marked sclerosis and avascularity of the lateral navicular. We describe our pathways for selecting arthrodesis based on the joints affected. Isolated talonavicular arthrodesis was performed in early stages of MWD, which begins at the talonavicular articulation. When disease extended to both sides of the navicular, we performed talonaviculocuneiform arthrodesis. When considering isolated talonavicular, double medial or triple arthrodesis, there should be adequate cancellous bone stock remaining in the lateral part of the navicular, as determined on medial oblique radiographs and CT scan. In case of inadequate bone stock or fracture through the lateral navicular, talonaviculocuneiform arthrodesis with interpositional iliac crest bone graft is recommended.

Simultaneous subtalar arthroeresis, midfoot soft tissue release, and talo-navicular arthrodesis in children with planovalgus neurologic foot.

PURPOSE: Planovalgus foot deformity (PVFD) is common in children with neuromuscular conditions and severe deformity may require surgical correction. This study aims to assess clinical and radiological outcomes of PVFD secondary to neuromuscular disease managed by subtalar arthroeresis (SuAE), midfoot soft tissue release and talo-navicular arthrodesis (TNA). METHODS: A retrospective analysis of children with neuromuscular disease and nonreducible PVFD who underwent SuAE, midfoot soft tissue release, and TNA and with a minimum follow-up of 5 years was performed. A total of 60 patients with neuromuscular disease (108 feet) including cerebral palsy were reviewed. Mean age at surgery was 12.7 ± 4.6 years (6-17). Mean follow-up was 7 ± 2.9 years (5-10). Clinical outcomes and radiologic correction at final follow-up were compared with preoperative values. Statistical analysis was performed and significance was set at P < 0.01. RESULTS: Statistically significant radiological improvements between pre- and postoperative values were found for all angle values. At final follow-up, there was a significant improvement in VAS score (4.8 vs. 2; P < 0.01). There was also a positive trend in the improvement of walking ability. No cases of pseudoarthrosis were reported at final follow-up. Screw removal was required in 5 out of 108 feet (4.6%) and 2 feet (3.3%) had delayed medial wound healing. CONCLUSIONS: SuAE combined with TNA and midfoot soft tissue is a safe and feasible procedure that can provide good clinical and radiologic results in patients with neuromuscular disease and nonreducible PVFD; the procedure can improve foot stability, and has a limited number of complications. LEVEL OF EVIDENCE: IV.

Imaging of Müller-Weiss Disease.

Müller-Weiss disease (MWD) is the result of a dysplasia of the tarsal navicular bone. Over the adult years, the dysplastic bone leads to the development of an asymmetric talonavicular arthritis with the talar head shifting laterally and plantarly, thus driving the subtalar joint into varus. From a diagnostic point of view, the condition may be difficult to differentiate from an avascular necrosis or even a stress fracture of the navicular, but fragmentation is the result of a mechanical impairment rather than a biological dysfunction.Standardized weight-bearing radiographs (anteroposterior and lateral views) of both feet are usually enough to diagnose MWD. Other imaging modalities such as multi-detector computed tomography and magnetic resonance imaging in early cases for the differential diagnosis can add additional details on the amount of cartilage affected, bone stock, fragmentation, and associated soft tissue injuries. Failure to identify patients with paradoxical flatfeet varus may lead to an incorrect diagnosis and management. Conservative treatment with the use of rigid insoles is effective in most patients. A calcaneal osteotomy seems to be a satisfactory treatment for patients who fail to respond to conservative measures and a good alternative to the different types of peri-navicular fusions. Weight-bearing radiographs are also useful to identify postoperative changes.

A retrospective magnetic resonance imaging analysis of bone and soft tissue changes associated with the spectrum of tarsal coalitions.

We aimed to investigate the bone and soft tissue changes accompanying tarsal coalition (TC) and aimed to evaluate their association with the location and type of coalition. Ankle magnetic resonance imagings of 65 patients with TC were included. The relationship between the location and type of coalition and bone marrow edema, subchondral cysts, sinus tarsi syndrome, tarsal tunnel syndrome, posterior impingement syndrome, accessory bone, tibiotalar effusion, talar osteochondritis dissecans, ganglion cysts, and calcaneal spur were evaluated. Twenty-nine patients without coalition were selected as the control group, and the distribution of these variables between the two groups was analyzed. There were 33 females and 32 males in the coalition group (mean age: 42.0 ± 15.63 years), and 22 females and seven males in the control group (mean age: 44.79 ± 12.33 years). Coalition was most common in the talocalcaneal joint (n = 33, 50.8%), and the most common coalition type was non-osseous (n = 57, 87.6%). We find no significant difference between the pathologies defined in terms of coalition location and type. Sinus tarsi syndrome, tarsal tunnel syndrome, subchondral cysts, and tibiotalar effusion were found to be more common in the coalition group (p = 0.028, p = 0.010, p = 0.023, and p = 0.006, respectively). The presence of coalition increased the probability of developing tarsal tunnel syndrome 9.91 times (95% CI: [1.25-78.59]; p = 0.029), and sinus tarsi syndrome 3.66 times (95% CI: [1.14-11.78]; p = 0.029). Tarsal coalition may predispose bone and soft tissue changes. In this study, sinus tarsi syndrome, tarsal tunnel syndrome, subchondral cysts and tibiotalar effusion were found to be more common in the coalition group.

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.

Towards understanding Müller-Weiss disease from an analysis of 95 cases.

BACKGROUND: The single existing classification of Müller-Weiss Disease (MWD), based solely upon Méary's angle, serves neither as guide for prognosis nor treatment. This accounts for lack of gold standard in its management. METHODS: Navicular compression, medial extrusion, metatarsal lengths, Kite's, lateral and dorsoplantar talo-first metatarsal angles were measured in 95 feet with MWD. Joints involved, presence and location of navicular fracture were recorded. RESULTS: Group 1 "early-onset" MWD feet (n = 11) had greatest compression and medial extrusion, and lowest Kite's angles. All except 1 were index minus and had lateral navicular fracture. Only 1 had moderate degeneration at the talonavicular joint (TNJ) with none requiring surgery yet. Group 2 "Müller-Weissoid" feet (n = 23) had radiologically normal navicular in their fifties and developed MWD on average 5 years later. They had the lowest compression and extrusion, and highest Kite's angles. None had complete fracture. All had TNJ arthritis, with early changes at lateral naviculocuneiform joint (NCJ) in 43%. Group 3 "late-onset" MWD presented in the sixth decade. Only TNJ was involved in Group 3 A (n = 16). Group 3B (n = 20) affected TNJ more than NCJ and had the greatest number of Maceira stage V disease. Group 3 C "reverse Müller-Weiss disease", which affected NCJ more than TNJ (n = 25), had greatest midfoot abduction and overlength of the second metatarsal. No fracture occurred in group 3 A compared to 65% and 32% in groups 3B and 3 C, respectively. CONCLUSIONS: With need to compare like-for-like pathology, the proposed classification provides a common platform for reporting outcomes of different treatments. We theorize pathogenetic pathways in the various groups.

The painful lateral column of the foot: from back to front.

The purpose of this article is to focus attention on the abnormalities which the radiologist may encounter in patients presenting with lateral ankle or foot pain outside of the context of acute trauma. These include anterolateral impingement, subfibular impingement, subtalar instability and tarsal sinus syndrome, tarsal coalition, sural neuromas, peroneal tendon abnormalities, calcaneocuboid instability and occult cuboid fractures, and painful accessory ossicles. The expected and unexpected findings on radiographs, CT, US, and MRI are discussed.

Bone stress injuries in the presence of tarsal coalition as a cause of hindfoot pain in adolescents: case series of 6 patients with literature review.

OBJECTIVE: To highlight causal relationship between stress fracture in the presence of tarsal coalition and hindfoot pain in adolescents on magnetic resonance imaging (MRI). MATERIAL AND METHODS: A retrospective review was performed of the clinical and MRI imaging findings of 6 adolescents referred for MRI to evaluate symptoms of hindfoot pain with possible tarsal coalition. MRI studies were systematically assessed for cause of hindfoot pain, types of tarsal coalition, patterns of stress fractures, bone marrow oedema and any other associated features. RESULTS: All the 6 patients (4 male: 2 female) aged between 12 and 19 years developed insidious onset of hindfoot or midfoot pain over a period of weeks to months. On MRI, all 6 cases had features of fibrous tarsal coalition predominantly in the calcaneonavicular articulation (5 out of 6 patients). Associated stress fractures/response were in the posterior facet/body of the calcaneus (3), talar head (2), cuboid (1) and third metatarsal bone in one patient. CONCLUSION: Stress fractures/response adjacent to tarsal coalition could be because of altered biomechanics and can be an unusual cause of hindfoot pain in adolescents. A high index of suspicion and complementary MRI findings is crucial to interpret this condition to direct appropriate patient management.

Osteochondritis dissecans of the talar dome in patients with tarsal coalition.

OBJECTIVE: Tarsal coalition is known to cause abnormal talocrural stress, hindfoot malalignment, and ankle sprains. These can all be associated with osteochondritis dissecans (OCD) of the talar dome. We present the first detailed description of a series of talar OCDs occurring in patients with tarsal coalition, with the goal of determining whether there is an increased prevalence of OCDs among patients with tarsal coalition. MATERIALS AND METHODS: We studied ankle MRIs in 57 patients with tarsal coalitions, excluding those with a reported inciting traumatic event. The MRIs were performed on magnetic field strengths ranging from 0.3 to 1.5 T and included axial, coronal, and sagittal T1 and T2 or PD fat-suppressed sequences. We evaluated the morphology and location of classically described OCDs in these patients, type and location of concomitant tarsal coalition, and, when available, the presence of pes planus and hindfoot valgus on weight-bearing radiographs. Chi-squared analysis was used to compare categorical variables and a Student's t test was used for parametric continuous variables. Additionally, logistic regression was used to compute the odds ratio of talar OCD associated with patient age, gender, laterality, pes planus status, hindfoot valgus status, and coalition type. RESULTS: Eighty-nine percent of tarsal coalitions were non-osseous coalitions and the calcaneonavicular space was the most common site of abnormal tarsal connection (54.4%). In the 29 patients with tarsal coalitions and talar OCDs, OCDs commonly occurred medially (75.9%). In the sagittal plane, talar OCDs occurred centrally, with only one case sparing the central talar dome. The mean surface area of the 29 OCDs was 89.7 mm2. Both osseous coalition and hindfoot valgus were associated with smaller talar OCD mean surface area (p = 0.015 and p = 0.0001, respectively). There was no association between depth and surface area of talar OCD with either coalition location or presence of pes planus (coalition location: p = 0.455 for depth and p = 0.295 for surface area; presence of pes planus: p = 0.593 for depth and p = 0.367 for surface area). CONCLUSION: Talar OCD prevalence is higher in patients with tarsal coalition than that reported for the general population. This occurrence may relate to altered biomechanics and repetitive talocrural stress owing to altered subtalar motion, particularly given the findings of increased odds of talar OCD in older patients, as well as weak associations between OCD surface area and both non-osseous coalition and hindfoot alignment. However, we did not find any specific OCD morphologic features attributable to the precise location of the tarsal coalition.

Risk Factors for Persistent Pain Requiring Surgical Treatment in Adult Symptomatic Accessory Navicular.

OBJECTIVE: Identifying the risk factors for persistent pain despite proper conservative treatment in adult symptomatic accessory navicular may reduce the need for surgical treatment. The aim of this study was to identify any such risk factors. DESIGN: Cohort study. SETTING: University hospital foot and ankle clinic. PATIENTS: A retrospective review of 313 patients who presented with adult symptomatic accessory navicular was performed. ASSESSMENT OF RISK FACTORS: Potential risk factors were identified via medical records and foot radiographs. The possible risk factors included age, gender, body mass index, smoking status, occurrence/cause of symptoms, occupation, type of accessory navicular, and radiographic foot parameters. MAIN OUTCOME MEASURES: Predictors that relate to persistent pain requiring surgical treatment in adult accessory navicular were analyzed using logistic regression analysis. RESULTS: Of the 313 patients included, 30 (9.6%) underwent surgical treatment due to failure of conservative treatment. The odds of needing surgical treatment decreased by 0.96 per year of age at symptom onset (P = 0.030), but those odds were 8.52 times higher in patients who had a type IIB accessory navicular (P = 0.001). Other variables did not reach statistical significance. CONCLUSIONS: Younger age at symptom onset and type IIB were the risk factors for persistent pain requiring surgical treatment in adult symptomatic accessory navicular.

Operative Outcomes for Accessory Navicular in Adolescents.

The purpose of this study is to report the operative outcomes in a consecutive series of adolescent patients with symptomatic accessory navicular (AN). A retrospective review was conducted. Patient characteristics, operative techniques, and outcomes were recorded. Radiographs were used to identify the type of AN, skeletal maturity, and presence of concurrent pes planus. Twenty-two patients and 24 feet were studied. All 22 patients had an excision of the AN, and 19 patients had an additional reefing of the tibialis posterior tendon. At final follow up, 22 cases reported no pain, one had minimal pain, and one reported no change in pain. Symptomatic AN is more common in females. Surgery technique was not correlated with postoperative pain. Surgery eliminated pain in 91% of patients and can be safely performed in athletes with high rate of return to their previous athletic performance. (Journal of Surgical Orthopaedic Advances 31(1):053-055, 2022).

Atypical Presentation of Navicular Aneurysmal Bone Cyst in a Symptomatic Pediatric Flatfoot Deformity: A Case Report.

Aneurysmal bone cysts (ABCs) are rare in the foot, accounting for 4% to 6.3% of all ABCs found in the body. Approximately 80% of patients diagnosed with an ABC are in the second decade of life. While benign, pain and deformity are often the presenting symptoms. This report's objective is to describe, to our knowledge, the first reported case of a pediatric navicular ABC in association with pediatric flatfoot deformity that was successfully treated with curettage and bone grafting. An additional goal of the report is to highlight how the diagnosis of these osseous tumors can easily be missed given the overlap in symptoms with pediatric flatfoot deformity. An 11-year-old female presented to clinic with a chief complaint of painful, flatfoot deformity and discomfort to the medial midfoot after walking for more than 2 city blocks. The patient was conservatively treated for pediatric flatfoot deformity at an outside institution and advised that a surgical flatfoot reconstruction would be necessary to relieve her symptomology. On examination, the patient exhibited focal pain to the medial aspect of the navicular. Radiographs revealed an ill-defined, expansile, sclerotic lesion of the navicular, and MRI demonstrated a multicystic lesion filling the navicular, consistent with an ABC. Treatment included curettage and packing with allograft. At 1-year follow-up, the patient is well, with minimal pain and return to full activity without functional limitations. Local recurrence of an aneurysmal bone cyst following curettage and bone grafting is as high as 22% with patient age and lesion size comprising the main risk factors. This report demonstrates successful curettage of an ABC within the navicular and preservation of osseous articulations in a pediatric patient. At 1-year follow-up, the patient had minimal pain with no evidence of recurrence.

Symptomatic Os Navicular on 99mTc-MDP SPECT/CT.

Os navicular bone is an accessory bone of the foot, which is mainly found on the medial side of the proximal navicular bone. Os navicular bone may be symptomatic and cause medial foot pain. We report a case of a 42-year-old athlete male having right foot pain diagnosed with os navicular syndrome on 99mTc-MDP bone scintigraphy SPECT/CT. We emphasize on the use of SPECT/CT in not only allocating the ossicle anatomically, but also for the purpose of evaluating an active source of pain in a region of multiple complex small bones.

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.

Treatment of Navicular Stress Fracture Accompanied by Os Supranaviculare: A Case Report.

Navicular stress fractures (NSFs) are relatively uncommon, and predominantly affect athletes. Patients complain of vague pain, bruising, and swelling in the dorsal aspect of the midfoot. Os supranaviculare (OSSN) is an accessory ossicle located above the dorsal aspect of the talonavicular joint. There have been few previous reports of NSFs accompanied by OSSN. Herein we report the case of a patient with OSSN who was successfully treated for an NSF. A 34-year-old Asian man presented with a 6-month history of insidious-onset dorsal foot pain that occasionally radiated medially toward the arch. The pain worsened while sprinting and kicking a soccer ball with the instep, whereas it was temporarily relieved by rest for a week and analgesics. Plain radiographs of the weight-bearing foot and ankle joints revealed a bilateral, well-corticated OSSN. Computed tomography (CT) revealed a sagittally oriented incomplete fracture that extended from the dorsoproximal cortex to the center of the body of the navicular. The OSSN was excised and the joint was immobilized with a non-weight-bearing cast for 6 weeks, followed by gradual weight bearing using a boot. The 5-month follow-up CT scan demonstrated definite fracture healing. At the 1-year follow-up, the patient's symptoms had resolved, the American Orthopedic Foot and Ankle Society midfoot score had improved from 61 to 95 points, and the visual analog scale pain score had improved from 6 to 0. We describe a rare case of NSF accompanied by OSSN. Because of the fracture gap and biomechanical properties of OSSN, OSSN was excised and the joint was immobilized, leading to a successful outcome. Further research is required to evaluate the relationship between NSFs and OSSN, and determine the optimal management of NSFs in patients with OSSN.