Search Results
Are Three-Dimensional–Printed Foot Orthoses Able to Cover the Podiatric Physician's Needs?
Relationship Between Shore A Hardness and Infilling Density
Background
Current management of foot pain requires foot orthoses (FOs) with various design features (eg, wedging, height) and specific mechanical properties (eg, hardness, volume). Development of additive manufacturing (three-dimensional [3-D] printing) raises the question of applying its technology to FO manufacturing. Recent studies have demonstrated the physical benefits of FO parts with specific mechanical properties, but none have investigated the relationship between honeycomb architecture (HcA) infilling density and Shore A hardness of thermoplastic polyurethane (TPU) used to make FOs, which is the aim of this study.
Methods
Sixteen different FO samples were made with a 3-D printer using TPU (97 Shore A), with HcA infilling density ranging from 10 to 40. The mean of two Shore A hardness measurements was used in regression analysis.
Results
Interdurometer reproducibility was excellent (intraclass correlation coefficient, 0.91; 95% confidence interval [CI], 0.64–0.98; P < .001) and interprinter reproducibility was excellent/good (intraclass correlation coefficient, 0.84; 95% CI, 0.43–0.96; P < .001). Linear regression showed a positive significant relationship between Shore A hardness and HcA infilling density (R2 = 0.955; P < .001). Concordance between evaluator and durometer was 86.7%.
Conclusions
This study revealed a strong relationship between Shore A hardness and HcA infilling density of TPU parts produced by 3-D printing and highlighted excellent concordance. These results are clinically relevant because 3-D printing can cover Shore A hardness values ranging from 40 to 70, representing most FO production needs. These results could provide important data for 3-D manufacturing of FOs to match the population needs.
INTRODUCTION AND OBJECTIVES: Melanoma is one of the most common primary malignant tumors arising in the lower extremity. It is crucial to diagnose melanoma as quickly and as efficiently as possible for a better prognosis. The use of dermoscopy is helpful in diagnosing such conditions. Dermoscopy is a non-invasive, in-vivo technique primarily used in the examination of pigmented skin lesions. This procedure allows the visualization of subsurface skin structures in the epidermis, dermoepidermal junction, and upper dermis - structures not visible to the naked eye. This poster presents the advantages of dermoscopy in the field of podiatry by assessing the dermoscopic criteria with positive predictive values for distinguishing acral melanoma from acral nevus. Additionally it analyzes cases of melanomas misdiagnosed as a plantar-pigmented wart and a diabetic ulcer.
METHODS: The authors used PubMed to perform an English language literature search. The exclusion criteria included articles older than 10 years. Inclusion criteria consisted of research done on humans and the terms dermoscopy and foot lesions or melanoma. After retrieving a total of 140 articles, 14 articles were found to meet both the inclusion and exclusion criteria.
RESULTS: Qualitative analysis of relevant articles demonstrates that the detection of malignant dermoscopic patterns enhances quick and correct diagnosis.
CONCLUSIONS: The use of dermoscopy is slowly evolving in podiatry. It aims to minimize the amount of biopsies taken, thereby decreasing the risk of creating an ulcer and reducing the patients exposure to anesthesia. While controversy remains over sensitivity and specificity of using a dermatoscope alone to diagnose pedal lesions, particular attention should be paid to the accuracy of diagnosing a lesion when dermoscopy is used in conjunction with a biopsy. With the continued usage of a dermatoscope along with experience and expertise in the field, the need for a biopsy could eventually be eliminated.
Osteoporosis is an asymptomatic disease until a fracture occurs. The prevalence of osteoporosis will rise with the aging of the population. Recent advances have led to more efficacious treatment options. Targeted screening, educating patients about preventive strategies, and providing appropriate treatment for those at high risk will allow physicians to reduce the enormous morbidity and mortality associated with osteoporosis. (J Am Podiatr Med Assoc 94(2): 187-193, 2004)
Athletic injuries of the foot and lower extremity are commonly treated with custom foot orthoses. These devices usually provide immediate relief of the athlete’s pain and dysfunction. Occasionally, however, they do not help, or even increase the patient’s discomfort. We discuss a method of using in-shoe pressure-measurement systems to analyze the athletic patient’s foot and lower-extremity function before and after treatment with custom foot orthoses, with a focus on sagittal plane biomechanics. Case histories are presented of athletes whose gait pathologies were identified and treated successfully using an in-shoe pressure-measurement system. (J Am Podiatr Med Assoc 97(1): 49–58, 2007)
