Metatarsal Research Articles

Phenytoin is associated with increased risk of osteoporosis and fragility fractures in adult epileptic patients.

Osteoporotic fractures lead to significant decreases in the quality of life with increases in morbidity, mortality, and disability. Treatment with a variety of anti-epileptic drugs, such as phenytoin, has been understood to cause a decrease in bone mineral density. Cohort A was identified as patients that were 18-55years old that had epilepsy and recurrent seizures that were also prescribed phenytoin. Cohort B was identified as patients that were 18-55years old that had epilepsy and recurrent seizures but were not prescribed phenytoin or other anti-epileptic medications. Cohorts were matched for relevant confounding pathologies and demographic factors. Outcomes were evaluated from 1day to 5years after the indexed event. A total of 35,936 patients with epilepsy that were prescribed phenytoin were matched with 109,335 patients with epilepsy that were not prescribed phenytoin. Patients on phenytoin therapy were at significantly higher risk for osteoporosis without pathological fracture, fracture of metatarsal bone, fracture of shoulder and upper arm, fracture of distal radius, fracture of thoracic vertebra, fracture of cervical vertebra, fracture of lumbar vertebra, fracture of femoral head or neck, pertrochanteric fracture, femoral shaft fracture, and distal tibia fracture (all outcomes p < 0.001). Epileptic patients on phenytoin therapy that were 18-55years old exhibited higher associated risk of osteoporosis and osteoporotic-fragility fractures of various regions. Patients that undergo phenytoin therapy for epilepsy treatment should be educated on the increased risk of bone fractures and have appropriate lifestyle and diet modifications.

Can the Entire Function of the Foot Be Concentrated in the Forefoot Area during the Running Stance Phase? A Finite Element Study of Different Shoe Soles.

The goal of this study was to use the finite element (FE) method to compare and study the differences between bionic shoes (BS) and normal shoes (NS) forefoot strike patterns when running. In addition, we separated the forefoot area when forefoot running as a way to create a small and independent area of instability. An adult male of Chinese descent was recruited for this investigation (age: 26 years old; body height: 185 cm; body mass: 82 kg) (forefoot strike patterns). We analyzed forefoot running under two different conditions through FE analysis, and used bone stress distribution feature classification and recognition for further analysis. The metatarsal stress values in forefoot strike patterns with BS were less than with NS. Additionally, the bone stress classification of features and the recognition accuracy rate of metatarsal (MT) 2, MT3 and MT5 were higher than other foot bones in the first 5%, 10%, 20% and 50% of nodes. BS forefoot running helped reduce the probability of occurrence of metatarsal stress fractures. In addition, the findings further revealed that BS may have important implications for the prevention of hallux valgus, which may be more effective in adolescent children. Finally, this study presents a post-processing method for FE results, which is of great significance for further understanding and exploration of FE results.

Biomechanical substantiation of the algorithm for choosing the type of corrective osteotomy of the fifth metatarsal bone in the treatment of tailor’s bunion

Background. Joint deformity between the main phalanx of the fifth toe and the fifth metatarsal bone is called tailor’s bunion. Its treatment is most often surgical. At the same time, there is no unified single approach regarding the use of osteotomies, their type and localization on the metatarsal bone (distal, diaphyseal, and proximal). Goal: based on the biomechanical studies, to substantiate the corrective possibilities of Weil and chevron distal osteotomies to correct valgus deformity of the fifth metatarsal bone depending on its geometric parameters. Materials and methods. Two types of corrective osteotomies were modeled: Weil and chevron osteotomy. We determined the maximum possible values of valgus deformity of the fifth metatarsal bone, which can be eliminated with the help of these osteotomies, depending on the geometric parameters of the fifth metatarsal bone. To determine the latter, radiometry was performed on 39 digital radiographs of the patients’ feet. Results. Taking into account the relatively small angular deviation of the fifth metatarsal bone whose value is most often observed in the range from 10 to 15° at the norm of 8°, the angular deformity can be compensated by linear displacement of the head of the metatarsal bone. Since the head displacement is performed in the horizontal plane, both osteotomies in this case work equally. The zone of maximum possible correction for deformity is determined within the range from 12°, with a length of 60 mm and a diameter of 8 mm, to 15.5°, with a length of 45 mm and a diameter of 12 mm. Given that there is some balance between bone length and diameter, the maximum deformity that can be corrected with Weil and chevron corrective osteotomies is a deformity of up to 14°. Conclusions. Weil and chevron corrective osteotomies can be used to correct the fifth metatarsal valgus deformity (tailor’s bunion) and are effective when the M4M5 angle does not exceed 14°. In cases where the M4M5 angle exceeds 15°, it is advisable to use proximal corrective osteotomies of the fifth metatarsal bone for the treatment of tailor’s bunion.

The plantar proximal cortex of the third metatarsal bone shows raised longitudinal ridges at the suspensory ligament enthesis in normal equine isolated limbs - a radiographic, computed tomography, and MRI study.

Knowledge of normal radiographic appearance is essential to avoid misinterpretation of radiographs. This study aimed to assess the computed tomographic (CT) appearance of the plantar surface of the proximal metatarsus and evaluate the influence of the radiographic angle on the trabecular/cortical interface of the proximal plantar metatarsal cortex on lateromedial and slightly oblique radiographs. Eight hindlimbs were collected from six horses with no known history of lameness and euthanized for reasons unrelated to the study. Limbs underwent computed tomographic (CT) and radiographic examination (dorsoplantar, lateromedial, and slightly oblique radiographic views obtained by angling the beam dorsally and plantarly from the plane used for the lateromedial projection). Standing magnetic resonance (MR) imaging and computed tomography (CT) were used to confirm normalcy. Images were compared side-by-side by two experienced readers. Limbs were normal at MR imaging. Longitudinal linear ridges were present on the proximal plantar metatarsal surface in all limbs (1-2 sagittal ridges and 1 ridge located at the medial or lateral margin of the suspensory ligament). Longitudinal ridges were positioned facing an adipose-muscular bundle of the suspensory ligament on CT images and were visible as linearly increased opacities on dorsoplantar radiographs. The delineation of the trabecular/cortical interface of the proximal metatarsus changed with radiographic projection and was the sharpest on the plantaro 85° lateral to the dorsomedial oblique view. The proximal third metatarsal bone shows individual morphological variations, with longitudinal linear ridges that alter the bone homogeneity on dorsoplantar radiographs. An oblique plantaro 85° lateral to the dorsomedial view is suggested to better assess the presence of subcortical sclerosis when proximal suspensory enthesopathy is suspected.

Numerical Simulation of the Effect of Different Footwear Midsole Structures on Plantar Pressure Distribution and Bone Stress in Obese and Healthy Children.

The foot, as the foundation of the human body, bears the vast majority of the body's weight. Obese children bear more weight than healthy children in the process of walking and running. This study compared three footwear midsole structures (solid, lattice, and chiral) based on plantar pressure distribution and bone stress in obese and healthy children through numerical simulation. The preparation for the study included obtaining a thin-slice CT scan of a healthy 9-year-old boy's right foot, and this study distinguished between a healthy and an obese child by applying external loadings of 25 kg and 50 kg in the finite element models. The simulation results showed that the plantar pressure was mainly concentrated in the forefoot and heel due to the distribution of gravity (first metatarsal, fourth metatarsal, and heel bone, corresponding to plantar regions M1, M4, and HM and HL) on the foot in normal standing. Compared with the lattice and solid EVA structures, in both healthy and obese children, the percentage reduction in plantar pressure due to the chiral structure in the areas M1, M4, HM, and HL was the largest with values of 38.69%, 34.25%, 64.24%, and 54.03% for an obese child and 33.99%, 28.25%, 56.08%, and 56.96% for a healthy child. On the other hand, higher pressures (15.19 kPa for an obese child and 5.42 kPa for a healthy child) were observed in the MF area when using the chiral structure than when using the other two structures, which means that this structure can transfer an amount of pressure from the heel to the arch, resulting in a release in the pressure at the heel region and providing support at the arch. In addition, the study found that the chiral structure was not highly sensitive to the external application of body weight. This indicates that the chiral structure is more stable than the other two structures and is minimally affected by changes in external conditions. The findings in this research lay the groundwork for clinical prevention and intervention in foot disorders in obese children and provide new research ideas for shoe midsole manufacturers.

Medical simulator for the training of radiologists: experimental work

BACKGROUND: Ankle injuries of various nature bruises, sprains, tears, dislocations and subluxations, and fractures account for 2030% of all musculoskeletal system injuries. The most common ankle injuries are a tear and sprain. The difficulty in treating fractures in this location is due to the need for accurate repositioning of the articular surface and stable fixation of fragments. The actual task is to train roentgenologists in the field. The inclusion of medical personnel in the educational process at all levels of training simulation courses aids in the reduction of errors, reduction of problems, and the improvement of the quality of medical treatment provided to the public.&#x0D; OBJECTIVE: This study aims to develop and create a simulator that simulates human bone structure and soft tissues and allows roentgenologists to get through training and instruction radiological examinations of an ankle joint and a foot.&#x0D; MATERIALS AND METHODS: The following stages of the simulators development have been completed: acquiring ankle bone samples, creating a mold for casting, and constructing the simulator. The results of computer and magnetic resonance imaging were used to construct bone samples, from which a computerized 3D model of the bones of the foot and ankle joint was obtained. Using additive technologies, anatomically correct reproductions of human foot and ankle bones were made. At the next stage, a three-dimensional digital model was developed, and a mold for casting the finished product was made. Bone samples collected in a single structure were placed inside the mold. Next, a step-by-step filling of the form with a soft gel-like material was performed. In this case, a self-vulcanizing silicone rubber composition is selected, which, after solidification, imitates human soft tissues.&#x0D; RESULTS: During the course of the study, a prototype medical simulator was created that models human bone structure and soft tissues and allows roentgenologists to practice performing ankle joint and foot roentgenography.&#x0D; CONCLUSION: Because of its high anatomical accuracy, ease of use, and mass production potential, the developed simulator can be widely employed in the teaching of roentgenologists.

Analysis of medium-term outcomes after surgical correction hallux valgus deformity

BACKGROUND: One of the most prevalent foot abnormalities is valgus deformity of the first toe. Many procedures have been proposed to correct this deformity, but one of the most Scarf osteotomy of the first metatarsal bone, which is complemented by the Akin osteotomy of the proximal phalanx of the first finger, is one of the most widely used. This publication analyzes the mid-term effect of repairing the deformity of the first toe using the methods described above.&#x0D; AIMS: To evaluate the mid-term outcomes of hallux valgus correction using Scarf osteotomy and the combination of Scarf and Akin osteotomies to the literature.&#x0D; MATERIALS AND METHODS: This is a cross-sectional, observational study. From January to December 2017, 129 patients (147 ft.) received forefoot deformity. Clinical and radiographic parameters were studied using the AOFAS, FFI, and VAS scales and questions related to the subjective assessment of patients by the treatment.&#x0D; RESULTS: The studys findings revealed an increase in AOFAS scores from 59.0 (1688, SD=18.6) before surgery to 85.0 (53100, SD=13.3; p 0.001) 5 yr later. The VAS scores fell from 5.7 (010, SD=2.2) to 2.4 (05, SD=1.4; p 0.001). After surgery, the FFI scale score decreased from 40.9 (1078, SD=18.1) to 11.3 (019, SD=5.0; p 0.001). According to the survey, 96.7% of patients would agree to a second operation, 96.9% of those who had surgery would recommend it to their relatives, and 94.6% were satisfied with the aesthetic result of the operation. Most patients (95.4%) were satisfied with the treatment in terms of the disappearance of pain and discomfort. The functional results of the surgical surgery were satisfactory to 98.4% of the patients who were consulted. Radiographic HVA, IMA angle, and Hardy and Clapham sesamoid position scores all indicated favorable mid-term outcomes with no deformity recurrence. In 46.3% of patients (68 patients), there was limited mobility in the first metatarsophalangeal joint. A complication in superficial soft tissue irritation occurred in four patients (2.7%). Iatrogenic varus deviation of one toe was observed in one patient. Metal fixators were removed from patients in 34 patients (23.1%). The removal was completed within a year in 17 cases (11.6%).&#x0D; CONCLUSIONS: Scarf osteotomy, alone or in combination with Akin osteotomy, is a successful treatment for hallux valgus.

High-resolution ultrasound and MRI in the evaluation of the forefoot and midfoot.

Radiography is the appropriate initial imaging modality to assess for midfoot and forefoot pathology before turning to advanced imaging techniques. While most lesions of the mid- and forefoot can be diagnosed clinically, the exact nature and severity of the pathology is often unclear. This review addresses the use of the ultrasound, as well as the added value of magnetic resonance imaging, in diagnosing conditions of the midfoot and forefoot. Ultrasound allows a dynamic assessment as well as enabling imaging-guided interventions for diagnostic and therapeutic purposes. Practical tips for optimal examination of this area with ultrasound and magnetic resonance imaging are provided. Metatarsal stress fracture, Chopart's injury, Lisfranc injury, as well as the 1st metatarsophalangeal joint injury and lesser metatarsophalangeal plantar plate injury are injuries unique to the mid- and forefoot. The imaging anatomy of the 1st and lesser metatarsophalangeal joints is reviewed, as such knowledge is key to correctly assessing injury of these joints. Characteristic imaging features of masses commonly encountered in the mid- and forefoot, such as ganglion cyst, Morton neuroma, gouty tophus, plantar fibroma, foreign body granuloma, and leiomyoma are reviewed. The use of ultrasound and magnetic resonance imaging in assessing degenerative and inflammatory joint disorders, and in particular rheumatoid arthritis, of the mid- and forefoot region is also reviewed. In summary, when necessary, most lesions of the mid-and forefoot can be adequately assessed with ultrasound, supplemented on occasion with radiographs, computed tomography, or magnetic resonance imaging.

Determination of Bone Developments of Rat Anterior and Posterior Extremity Bones in Prenatal and Postnatal Period by Double Staining Method

Aim: In our study, we aimed to determine the morphological development of the bones of the anterior and posterior extremity by staining the rat fetus and offspring skeletons with the double staining method. Method: In the current study, seven groups three prenatal (16th, 18th, and 20th days) and four postnatal (0th, 3th, 7th and 12th days) were formed from the foetuses and offsprings obtained from 13 pregnant rats. Then, it was stained with double staining method. Anterior and posterior extremity images of the fetuses and offsprings were examined under a stereo microscope, and ossification findings were determined. Total bone and ossification lengths as well as ossification areas were measured using the ImageJ software. Results: The first cartilage destruction in fetuses occurred on the 16th day of pregnancy in the clavicle, scapula, humerus, radius and ulna; It was seen in the femur, tibia and fibula on the 18th day of pregnancy. The first ossification centres were in the clavicle, scapula and humerus on the 18th day of pregnancy; It was seen in the radius, ulna, femur, tibia, fibula and 2-5 metatarsal bones on the 20th day of pregnancy. The secondary ossification centre was seen on the 0th day (birthday) in the scapula and humerus, on the 7th day after birth in the ulna and radius, and on the 12th day after birth in the femur and tibia. In the study, while the ossification rate in 20-day-old foetuses was 48.9% in the humerus, 53.2% in the radius, 55.7% in the ulna, 33.6% in the femur, 43.2% in the tibia, 44.3% in the fibula, it was determined that it reached 69.7% in the humerus, 78.4% in the radius, 73.3% in the ulna, 63.5% in the femur, 75.5% in the tibia, and 69.2% in the fibula on the 12th day after birth. Conclusion: In this study, we revealed the morphological changes of the anterior and posterior extremity bones of fetuses and offsprings in the normal developmental course. We think that these results will shed light on the studies to be conducted on the detection of skeletal anomalies in teratological studies and contribute to a more comprehensive evaluation of the findings to be obtained from the studies to be conducted.

Foot Plantar Pressure Abnormalities in Near Adulthood Patients with Type 1 Diabetes.

Increased ulcer risk diminishes the quality of life in diabetes. This study assessed abnormalities in foot plantar pressure distribution in adolescents with T1D to detect early signs of ulcer risk. A total of 102 T1D patients, without diabetic neuropathy, were included (mean age 17.8 years, mean diabetes duration 7.4 year). Pedography was captured using Novel emed. Data from the study group were compared with reference data. The study revealed a statistically significant reduced foot contact area in both feet in the entire foot and under the head of the fifth metatarsal bone and the second toe. In both feet, the peak pressure was increased under the entire foot, hindfoot, midfoot, first metatarsal head, big toe, and second toe. There was no statistically significant difference in peak pressure. The mean plantar pressure rating was statistically significantly increased in both feet across the entire sole, in the hindfoot, midfoot, and first metatarsal head. T1D patients of age near adulthood without neuropathy have increased values in mean pressure and reduced contact area, pointing to the need of monitoring and preventive measures. These results point to the need of further research and analysis which should include various risk factor such as foot anatomy, body posture, or certain metabolic factors.

Impact of maternal topiramate ingestion on ossification of skull and appendicular bones in rat fetuses

The skull and appendicular bones are derived from different embryological sources during their development. The impact of prenatal exposure of topiramate on ossification of these bones is not adequately studied. The goal of this study was to assess the ossification patterns of the craniofacial bones and bones of the forelimbs and hindlimbs in 20-day-old rat fetuses after maternal exposure to topiramate at doses equivalent to human therapeutic doses. Three groups of Sprague-Dawley pregnant rats were used: control, topiramate 50mg/kg/day (T50) and topiramate 100mg/kg/day (T100). Topiramate was given by oral gavage from day 6 to day19 of gestation. Ossification was evaluated in the bones of 20 days fetuses after staining with Alizarin red. Results showed a significant reduction in complete ossified centers of the metacarpal, metatarsal and craniofacial bones in topiramate-exposed fetuses at both doses when compared to the control group. Also, a significant decrease in the length of ossified part of the long bones of the forelimbs and hindlimbs in topiramate-exposed fetuses at both doses was noted when compared to the control group. Crown-rump length and fetal weight were significantly decreased in topiramate treated groups compared to the control group. In all examined groups, there was a positive correlation between the crown-rump length and the lengths of humerus and femur. No abnormalities in the ossified bones and no significant changes in their ossification pattern were observed between the treated groups. In conclusion, prenatal administration of topiramate in doses equivalent to human therapeutic doses delayed ossification and development of craniofacial and appendicular bones in rat fetuses and their effects are not dose dependent at doses investigated. The implications of these findings in women who require topiramate therapy in pregnancy merit further evaluation.

Comparison between ZOOMit DWI and conventional DWI in the assessment of foot and ankle infection: a prospective study.

The study aimed to compare ZOOMit diffusion-weighted imaging (DWI) MRI with conventional DWI MRI for visualizing small bones in the foot, soft tissue abscesses, and osteomyelitis. The cohort consisted of a consecutive series of patients with potential foot and ankle infections referred for MR imaging. Patients were imaged using both conventional and ZOOMit DWI in the same setting. Blinded reads were then conducted in separate settings and independent of known clinical diagnosis by two expert radiologists. The results from the reads were compared statistically using paired t-tests and with biopsy specimen analysis, both anatomopathological and microbiological. There was improvement in fat suppression using ZOOMit sequence compared to conventional DWI (p = .001) with no significant difference in motion artifacts (p = .278). ZOOMit had a higher rate of concordance with pathology findings for osteomyelitis (72%, 31/43 cases) compared with conventional DWI (60%, 26/43 cases). ZOOMit also identified 46 additional small bones of the foot and ankle (405/596, 68.0%) than conventional DWI (359/596, 60.2%). Conventional DWI however exhibited a more negative contrast-to-noise ratio (CNR) than ZOOMit (p = 0.001). ZOOMit DWI improves distal extremity proton diffusion assessment and helps visualize more bones in the foot, with less image distortion and improved fat saturation at the expense of reduced CNR. This makes it a viable option for assessing lower extremity infections. This study highlights the novel utilization of ZOOMit diffusion-weighted imaging (DWI) for the assessment of lower extremity lesions compared to conventional DWI. • Distal extremity diffusion-weighted imaging (DWI) is often limited. • ZOOMit DWI displayed improved fat suppression with less motion artifacts and better visualization of the lower extremity bones than conventional DWI. • ZOOMit shows decreased contrast-to-noise ratio than conventional DWI.

BIOMECHANICAL SUBSTANTIATION OF THE ALGORITHM FOR CHOOSING THE OPTION OF DISTAL CORRECTIVE OSTEOTOMY OF THE II–IV METATARSAL BONES IN THE TREATMENT OF METATARSALGIA

Deformations of the front part of the foot with valgus deformity of the first toe lead to a redistribution of the body weight load during walking between the heads of the metatarsal bones. At the same time, the load on the head of II and III, and sometimes IV metatarsal bones increases significantly. Objective. To substantiate the choice of the most correct distal metatarsal osteotomy for the treatment of patients with metatarsalgia. Materials and methods. Three variants of distal metatarsal osteotomy were simulated: Weil, Helal, and distal wedge-shaped metatarsal osteotomy. Result. Weil osteotomy allows you to raise the support point of the metatarsal head above the support surface from 2 to 7 mm, depending on the amount of displacement of the head in the proximal direction and the angle of inclination of the metatarsal bone relative to the plane of the support surface, which effectively reduces the load on the metatarsal head during walking, but under conditions of magnitude the angle of inclination of the axis of the metatarsal bone is more than 20°. Helal osteotomy with the subsequent displacement of the separated part proximally, ensures the lifting of the head above the conventional plane of support from 1 to 4 mm, contributes to the effective unloading of the head while standing and while walking. They are used only for severe metatarsalgia. The range of correction of the standing height of the support surface of the metatarsal head for performing a distal wedgeshaped osteotomy is determined to be from 0.6 to 2.9 mm. Its advantage is the independence of the amount of correction from the presence or absence of a decrease in the longitudinal arch of the foot. Conclusions. Weil osteotomy has the worst corrective possibilities of raising the head of the metatarsal bone, but is very easy to perform, so its use is advisable in the absence of reduction of the longitudinal arch of the foot. A wedge-shaped distal osteotomy has a range of correction of the metatarsal headelevation up to 3 mm, but it depends on its diameter, so it is used in the case of a head diameter of at least 10 mm. Helal osteotomy provides the widest range of elevation of the metatarsal head, which does not depend on the presence of any degree of flat feet, but has some technical limitations.

SAT190 The Effect Of Mechanical Loading On Bone Growth Ex Vivo

Abstract Disclosure: T. Aeppli: None. Z. Zhang: None. F. Zaman: None. L.S. Savendahl: None. Background: Bone growth is a multi-step process that involves proliferation and differentiation of chondrocytes within the growth plate. Apart from local regulation by various signaling pathways, chondrocytes respond also to external cues such as nutrition, inflammation and mechanical load that may increase or stunt growth. The Hueuter and Volkmann law describes the effect of mechanical loading on bone growth stating that bone growth is inhibited by increased mechanical compression and is promoted by reduced loading. To this date, no data is available investigating the local effects of mechanical loading on bone growth in the absence of systemic growth factors in small embryonic bones. Aim: The aim was to study the effects of mechanical loading on bone growth in an ex vivo bone culture model. Methods: Cultured femur and metatarsal bones from rats (E19.5) were studied and local/direct effects of mechanical loading on bone growth were investigated. A range of different mechanical forces was applied to femur and metatarsal bones every 2-3 days. To monitor bone growth, digital pictures were taken and bone length was measured every 2-3 days. The loaded bones were compared to control bones (sham-loaded). Results: When applying different mechanical load to metatarsal bones, bone growth was suppressed in a dose-dependent manner. On day 5, after applying mechanical loading (0.4 N) twice on day 0 and 2, metatarsal bone growth was significantly suppressed when compared to unloaded control bones (p&amp;lt;0.05). In contrast, when mechanical loading was applied repetitively to femur bones, bone growth was significantly stimulated (p&amp;lt;0.001) when compared to unloaded control bones. Conclusion: In conclusion, depending on the type of bone (embryonic rat metatarsal bone and the larger rat femur bone) mechanical loading exerts opposite effects on bone growth in an ex vivo culture model. The effect of mechanical loading on bone growth requires further in vivo investigations to increase our understanding on the role of mechanical loading in different bones and bone growth disorders. Presentation: Saturday, June 17, 2023

THU459 Hypophosphatasia With Normal ALPL Gene Test; A Case Report

Abstract Disclosure: K. Alkwatli: None. L.Z. Khan: None. Introduction: Hypophosphatasia is a rare hereditary disorder caused by loss of tissue nonspecific alkaline phosphatase activity, an essential enzyme in phosphate metabolism. Severe cases present perinatally and in early childhood. Mild cases can present in adulthood and can be misdiagnosed. We present an interesting patient who was clinically diagnosed with hypophosphatasia despite negative molecular genetic testing. Case presentation: 40 years-old female with a history of fibromyalgia and multiple bone fractures presented to the clinic with a long-standing history of multiple cavities, severe fatigue, headaches, muscle cramps, and arthralgia. The patient had numerous fractures throughout her life that started at age five without significant trauma, including wrist, forearm, and metatarsal bones. Her family history was negative. Laboratory testing showed low alkaline phosphatase levels on multiple occasions, 28,29,30 U/L (reference range 34-123). Her vitamin B6 was elevated at 309 nmol/L (20-125). Her zinc, calcium, vitamin D, and liver function tests were all within normal limits. Bone density scan showed a Z score of -1.0 at the lumbar spine and a Z score of -0.3 at the left femoral neck. Molecular genetic testing of the ALPL gene was negative. Hypophosphatasia was diagnosed based on her clinical and lab assessments, and she is being treated with Asfotase alfa. Her clinical course is yet to be determined. Discussion: ALPL gene is responsible for encoding the tissue nonspecific alkaline phosphatase (TNALP), the main enzyme affected in patients with hypophosphatasia. TNALP degrades inorganic pyrophosphate (PPi) to inorganic phosphate (Pi), an essential element for bone mineralization. It also facilitates vitamin B6 to cross the cell membranes. Therefore, loss of function mutations of the ALPL gene cause accumulation of PPi, which impairs the calcium-phosphate hemostasis and causes damage to multiple organs. In addition, the accumulation of the active form of vitamin B6 extracellularly can result in neurological damage.Patients present with a broad spectrum of musculoskeletal, renal, dental, and neurological symptoms. The variability of the phenotypic magnitudes is thought to be due to heterogeneity in the ALPL gene mutations. Over 400s of ALPL gene mutations have been identified in patients with hypophosphatasia. Novel variants are increasingly being reported.Negative genetic testing of the ALPL gene can still be seen in patients with hypophosphatasia due to either a variant that is undetectable by current testing methodology or if the causative gene/s are not on the ALPL gene panel. Conclusion: Genetic testing is helpful in confirming the disease and providing genetic counseling; however, treatment should still be considered if patients have sufficient clinical and laboratory findings. Presentation: Thursday, June 15, 2023

THU410 Retrospective Review Of Adults Patients With Suspected Or Confirmed Hypophosphatasia At The Penn Bone Center

Abstract Disclosure: R. Tran: None. C. Hvisdas: None. M. Riordan: None. L. Novotny: None. S. Kallish: None. K. Patel: None. M. Al Mukaddam: None. Abstract: Hypophosphatasia (HPP) is a rare inherited genetic disorder that affects the mineralization of bones and teeth. HPP is the result of a pathogenic variant involving the tissue nonspecific alkaline phosphatase (ALPL) gene. The clinical presentations of HPP greatly vary from serious perinatal manifestations (respiratory failure, seizures, and death) to mild manifestations in adulthood. In adults, hallmark signs and symptoms include early loss of primary or secondary teeth, osteoporosis, osteomalacia, recurring metatarsal stress fractures, and abnormal laboratory values, such as low alkaline phosphatase (ALP), elevated phosphoethanolamine, and elevated vitamin B6.The treatment and follow up of adults with HPP are not clearly described. This retrospective study characterizes 43 patients referred to the Penn Bone Center for suspected HPP. Twelve of the 43 patients had a confirmed HPP diagnosis based on both clinical presentations and evidence of variant in the ALPL gene. The twelve patients consisted of both female and male adults between the ages of 24 to 74. In addition, the patients had abnormal ALP levels, ranging between less than 5 to 38 units per liter (normal range: 38 to 126 U/L). Six of these patients had previous or current use of asfotase alfa with variable treatment response. Two patients decided to stop treatment due to lack of clinical benefit or worsening of symptoms while on asfotase alfa therapy. Biochemical and bone mineral density follow-up while on therapy has not been shown to be helpful in monitoring treatment response. Asfotase alfa is a subcutaneously administered synthetic human alkaline phosphatase that was approved by the Federal Drug Administration (FDA) in 2015 for treatment of perinatal/infantile- and juvenile-onset hypophosphatasia. However, the efficacy of treatment in adults remain unclear at this time. Further research is required to better define the natural progression of mild or adult-onset hypophosphatasia and the patients who would benefit from enzyme therapy. Presentation: Thursday, June 15, 2023

Outcomes of Hallux Valgus Corrective Osteotomy: A Tertiary Hospital Experience.

A common form of forefoot deformity, hallux valgus (HV) is characterized by a prominent first metatarsal head, lateral deviation of the hallux, and medial deviation of the first metatarsal bone. In the case of HV, corrective osteotomies are performed with good results and patient satisfaction. A retrospective cohort study of patients who underwent corrective osteotomy for hallux valgus from 2016 to 2022 was conducted at King Abdulaziz Medical City (KAMC), Riyadh, Saudi Arabia. Data were collected by chart review using the BestCARE system. IBM SPSS Statistics for Windows, Version 23.0 (Released 2015; IBM Corp., Armonk, New York, United States) was used for statistical analysis. Our study included 166 patients. The mean age of the patients was found to be 41.3 years old and about 152 (91.6%) of them were females. The most frequently reported comorbidity was hypertension (10.2%). The mean hallux valgus angle was found to be 36.1 ± 9.9 and the mean intermetatarsal angle was found to be 15 ± 4.4 degrees. Seventy-six (45.8%) patients underwent nonoperative management first. The mean age at diagnosis among males was found to be 28.5 ± 11.3 years and among females was 37.9 ± 14.4 years; a significant difference between means was noted (p-value = 0.019) with mean age at diagnosis in males being significantly lesser than in females. Significant improvement and reduction were seen in HV angle post surgery. Nearly half of the patients underwent nonoperative management first. Age at diagnosis is significantly younger in males compared to females.

Peroneus tertius revisited: The morphological variability of the bifurcated peroneus tertius insertion – An anatomical study

BackgroundThe peroneus tertius muscle (PT) is one of the extensor muscles of the lower leg, often described as a variable separation from the extensor digitorum longus muscle (EDL). According to literature it has six different types of insertion, one of them (Olewnik Type IV) having two tendons inserting to the fifth metatarsal bone (FMTB). Morphometric data about this type of insertion is sparse, especially the relation between the two tendons, albeit the PT is suspected to contribute to stress fractures of the FMTB. Therefore, we examined this type of insertion to give detailed information on the tendons, the insertion points and the respective relations. MethodsWe examined 27 lower extremities of embalmed human bodies (12 paired, 15 single sided; 12 right and 15 left) with a distinguishable PT with two tendons inserting to the FMTB (Olewnik IV). The specimens were obtained of an undergrad dissection program, which in turn obtained them from a body donation program. After dissection of the PT and photo documentation in situ, resection and measurement of morphological properties of the tendons were performed with the PT attached to the fifth metatarsal bone. ResultsResults of the respective measurements yielded a wide range of variation, especially in the insertion point of the anterior tendon on the fifth metatarsal and the relation between the two tendons, but with no significant difference between sides or sex, except for the length of the posterior tendon between sex. The distance between the base of the FMTB and posterior tendon varies from 0 to 9 mm, with one outlier at 24 mm (mean = 3.9 ± 4.8 mm), the distance between the insertions from 0 to 15 mm (mean = 4.7 ± 4.7 mm), resulting in how far of the FMTB the anterior tendon reaches varying from 17 to 60 mm (mean = 39.6 ± 11.5 mm) or 22–98% (mean = 64 ± 19%). ConclusionOur findings give a detailed overview of the morphological features the PTT can have, when attached with two tendons to the FMTB. Especially the varying relationship between those two insertions and varying point of the anterior insertion are of interest, as they might support its complex role in the occurrence of fractures of the fifth metatarsal by providing different amounts of torsional stress and its tendons can be used as tendon-grafts.

Variations in the Management of Zone 2 5th Metatarsal Fractures Based on Physician Specialty

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: There is a wide variation in the management of acute “Zone 2” 5th metatarsal (MT) base fractures. The purpose of this study was to quantify these differences and evaluate the effect of treating physician specialty. Methods: This was a retrospective cohort study of patients with acute Zone 2 5th MT fractures who presented to a single large, urban, academic medical center between December 2012 and April 2022. Zone 2 was defined as the region of the 5th MT base bordered by the 4th and 5th MT articulation on the oblique radiographic view. Logistic regression was used to evaluate the odds of undergoing operative treatment based on provider specialty. Results: A total of 633 patients presented with Zone 2 fractures during the study period. 40.6% of patients initially presented to the ED, 36.3% to an urgent care (UC) center, and 23.1% directly to the office. Ultimately, 57.2% of patients were treated by orthopedic surgeons, 39.6% by podiatrists, and 3.2% by primary care physicians. For patients treated nonoperatively, the management plan significantly differed by treating specialty. Compared to podiatrists, patients treated by orthopedic surgeons were more likely to be treated in a hard sole shoe (30.8% versus 7.6%, p&lt; 0.001) and less likely to be treated using a CAM boot (57.3% versus 76.3%, p&lt; 0.001). Similarly, patients treated by orthopedic surgeons were more likely to be made WBAT compared to patients treated by podiatrists (71.8% versus 42.0%, p&lt; 0.001). Conclusion: Overall, 2.5% of patients with Zone 2 metatarsal fractures were treated operatively. 0.5% of patients treated by orthopedic surgeons underwent surgery compared to 6.1% of patients treated by podiatrists (p=0.001). Furthermore, when controlling for age, sex, and time between injury and initial presentation to the office, the likelihood of undergoing operative treatment was still significantly greater when being treated by a podiatrist (OR=16.5, p=0.009). There is considerable heterogeneity among the treatment strategies for Zone 2 proximal 5th MT fractures. Compared to podiatrists, orthopedic surgeons are less likely to treat patients operatively and more likely to allow early weight bearing.

Lateral Column Overload in Modified Double vs Triple Arthrodesis: A Biomechanical Study

Category: Hindfoot; Basic Sciences/Biologics Introduction/Purpose: There are few comparative studies investigating differences between the modified double and triple arthrodesis of the hindfoot. Previous studies have suggested that stiffening the lateral column of the hindfoot can increase lateral plantar pressures, potentially precipitating lateral column pain. We sought to characterize the difference in forefoot plantar pressures between the native state, after talonavicular (TN)/subtalar (ST) arthrodesis and triple arthrodesis. Methods: Ten fresh-frozen cadaver legs were tested in 4 positions: neutral, dorsiflexion, inversion and eversion. Testing was done in a native state, after TN/ST arthrodesis then after triple arthrodesis for all 4 positions. Forefoot plantar pressures were recorded. Results: Peak pressures increased from the native state laterally underneath the 5th metatarsal (MT) head after TN/ST arthrodesis and triple arthrodesis respectively by 247% and 164% and fell medially underneath the 1st MT head to 38% and 41% in axially loaded legs at neutral (p &lt; 0.025) without a difference between arthrodesis groups. Similarly, 5th MT head pressures were significantly increased from the native state after TN/ST and triple arthrodesis in the legs mounted in eversion by 129% and 109% respectively (p &lt; 0.025), without differences between the two arthrodesis groups. Conclusion: In our cadaveric model of native, non-deformed legs, both a modified double (TN/ST) and triple arthrodesis led to increased lateral forefoot plantar pressures compared to the native state without a difference between the arthrodesis groups.