3D printed portable model for anatomical teaching of the inginal region

Description

Page 1 of 5 DESCRIPTIVE REPORT Portable 3D printed model for anatomical teaching of the inguinal region.

[001] There is growing concern among general surgery residents about not being competent enough to enter independent practice after completing residency. The current model of graduate surgical education is based on the principles of Dr. Halsted, more than 100 years ago: residents are expected to work closely with supervision and assume increasing responsibility as they gain proficiency. Since that time, progressive resident autonomy has been the main feature of surgical training.

[002] The hypothetical learning curve has 4 phases: beginning of training. Followed by an upward trajectory indicating how quickly performance improves. Third phase when the procedure can already be done independently and competently, with additional experience improving results. This being the fourth phase, the plateau.

[003] However, in an era of reduced training time for residents, there is a need to formalize forms of teaching beyond the traditional, in an attempt to reduce the gap between theory and practice, with the use, for example, of laparoscopic boxes, videolaparoscopy simulation courses and, specifically, learning on anatomical teaching models (3). In this context, the application of 3D printing technology emerges.

[004] Within the surgical field, 3D printing has been used to aid in training, create representative models, or construct biological products. By far the most popular and established application of 3D printing in the surgical field is within maxillofacial and orthopedic surgery, where there are several Petition 870260000362, dated 05 / 01 / 2026, page 6 / 10 Page 2 of 5 reports describing surgical planning and the production of implants or implant guides for surgical approaches. However, other applications are gaining prominence in this scenario, and the production of schematic anatomical models to facilitate surgical training is one of them.

[005] Inguinal surgery, particularly inguinal hernioplasty, essentially represents the first contact a surgeon in training has with surgical learning, and serves as an ideal teaching procedure at all levels of residency. Understanding the anatomy of this region is therefore essential for performing a successful surgery. A brief literature review reveals reoperation rates, in certain techniques, as high as 25%. This is due, among other things, to the faulty restructuring of the local anatomy, which is a fundamental factor for the correct repair of the defect.

[006] The concern is to integrate skills into daily simulation practices, and combining theory in a didactic session with a teaching model increases the effectiveness of the training. Therefore, investment in creating schematic teaching models for medical practice is necessary.

[007] The objective of the present invention is therefore a portable, 3D-printed schematic model for teaching the anatomy of the inguinal region.

[008] The device consists of a schematic anatomical model of the inguinal region, 3D printed, made of polylactic acid, tubular in shape, in two layers, connected by a Z-shaped tube, which contains the following structures highlighted in distinct geometric figures (straight lines, curved lines, crossed lines): superiorly: external oblique muscle, internal oblique muscle, inguinal ligament, femoral vein. Inferiorly: fascia Petition 870260000362, dated 05 / 01 / 2026, page 7 / 10 Page 3 of 5 transversalis, transversus abdominis muscle, epigastric vessels, pubic tubercle, inguinal ligament, femoral vein.

[009] The technology was developed from a portable, 3D-printed model of the anatomy of the inguinal region in a schematic way - developed in the Fusion 360 program, with schematic division of planes and reference points of the area, using didactic colors and shapes.

[010] The mold has a cylindrical shape, 15 cm long and 4 cm thick, divided into two distinct sections. The first section is the upper part of the cylinder, while the second section comprises the lower part.

[011] The sections are connected by a “z”-shaped tube, located in the middle of the cylinder when it is molded, running longitudinally inside it and exiting through two holes, one in each hemicircle, located distally in the upper one and proximally in the lower one.

[012] This division was made in order to allow for the understanding and schematic identification of the external and internal anatomical structures of the specimen, as identified in the figures.

[013] Externally, the superior section has irregular grooves on the proximal border, which comprise the aponeurotic fibers of the internal oblique muscle (IOM). The parallel straight grooves that extend along almost its entire surface correspond to the aponeurotic fibers of the external oblique muscle (EOM). And a single, longer, curvilinear groove, arranged discontinuously between the parallel straight grooves, to give the effect of being located below them, is where the ilioinguinal nerve is found. Finally, a distal circular orifice, which corresponds to the superficial inguinal ring (figure 1). Petition 870260000362, dated 05 / 01 / 2026, page 8 / 10 Page 4 of 5

[014] Internally, the upper section contains the parallel straight grooves (MOE) and the inner face of the distal circular orifice that corresponds to the superficial inguinal ring (figure 2).

[015] Externally, the lower hemi-cylinder displays a series of S-shaped patterns distributed along its entire length, schematically corresponding to the fibers of the transversalis fascia. Four pairs of larger “S” figures, arranged perpendicularly to the previous ones, form the inferior epigastric vessels. Finally, a circular orifice represents the deep inguinal ring (figure 3). Internally, the “S” figures are again observed in sequence, representing the transversalis fascia and the inner face of the deep inguinal ring, represented by the circular orifice (figure 4).

[016] On the lateral wall, in the upper and lower sections, are the inguinal ligament, represented by the series of “X”s. And the distal circular drawing, which is completed at the junction of the upper and lower sections, corresponds to the femoral vein (figure 5).

[017] On the medial wall of the lower section, there are two parallel lines along the wall, corresponding to the union of the fibers of the transversus abdominis muscle and the internal oblique muscle. At the end of it, distal in the specimen, there are four "X" markings, dispersed in two lines, representing the bony thickening of the pubic tubercle (figure 6). The outer face of the medial wall mirrors the same structures on the outside of the specimen (figure 7).

[018] It is understood that when the present invention is put into practice, modifications may be added with regard to certain details of its construction, form and updating, without this implying a departure from the fundamental principles that are clearly substantiated in the claims, being Petition 870260000362, dated 05 / 01 / 2026, page 9 / 10 Page 5 of 5, it is understood that the terminology used was not intended to be limiting.

[019] In order to facilitate the understanding of the particulars of this invention, as well as according to a preferred practical application thereof, a detailed description of the figures is presented. Along with this description, annexes are included containing a set of drawings that illustrate, in an exemplary, though not restrictive, manner, its operation.

[020] Figure 1 illustrates the superior section - external surface: a) internal oblique muscle (IOM); b) external oblique muscle (EOM); c) ilioinguinal nerve; d) superficial inguinal ring, while Figure 2 shows the superior section - internal surface: a) external oblique muscle (EOM); b) final portion of the EOM (transition to the inguinal ligament); and c) superficial inguinal ring.

[021] Figure 3 represents the lower section - inner surface: a) transversalis fascia and; b) deep inguinal ring, while Figure 4 shows the inner section - outer surface: a) transversalis fascia; b) inferior epigastric vessels and; c) deep inguinal ring.

[022] Figure 5 shows the lateral-internal wall: a) external oblique muscle (EOM); b) final portion of the EOM (transition to the inguinal ligament); c) inguinal ligament; d) transversalis fascia; and e) femoral vein.

[023] Figure 6 represents the medial-internal wall: a) external oblique muscle (EOM); b) transversus abdominis muscle (TA) + internal oblique muscle (IOM); c) transversalis fascia; and d) pubic tubercle, while Figure 7 illustrates the medial-external wall: a) transversus abdominis muscle (TA) + internal oblique muscle (IOM); and b) pubic tubercle (PT). Petition 870260000362, dated 05 / 01 / 2026, page 10 / 10

Claims

Page 1 of 3 CLAIMS 1. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION characterized by consisting of a portable, 3D printed model of the anatomy of the inguinal region in a schematic form and developed in the Fusion 360 program, with schematic division of planes and reference points of the area, using didactic colors and shapes.

2. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claim 1, characterized by being manufactured in polylactic acid, tubular shape, in two layers, connected by a z-shaped tube.

3. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1 and 2, characterized by containing the following structures highlighted in distinct geometric figures (straight lines, curved lines, crossed lines): superiorly: external oblique muscle, internal oblique muscle, inguinal ligament, femoral vein and, inferiorly: transversalis fascia, transversus abdominis muscle, epigastric vessels, pubic tubercle, inguinal ligament, femoral vein.

4. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2 and 3, characterized by a cylindrical mold, 15 cm long and 4 cm thick, divided into two distinct sections, where the first section represents the upper part of the cylinder, while the second section comprises the lower part. Petition 870250089937, dated 02 / 10 / 2025, page 5 / 7 Page 2 of 3 5. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2, 3 and 4, characterized by sections connected by a “z” shaped tube, located in the middle of the cylinder when it is molded, running longitudinally inside it and exiting through two holes, one in each hemicircle, located distally in the upper one and proximally in the lower one.

6. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2, 3, 4 and 5, characterized by an outer upper section with irregular grooves on the proximal border, comprising the fibers of the aponeurosis of the internal oblique muscle (IOM).

7. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2, 3, 4, 5 and 6, characterized by having parallel straight grooves that extend along practically its entire surface, which correspond to the aponeurotic fibers of the external oblique muscle (EOM), having a single, longer and curvilinear groove, arranged discontinuously between the parallel straight grooves, to give the effect that the ilioinguinal nerve is located below them, and also having a distal circular orifice, which corresponds to the superficial inguinal ring.

8. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2, 3, 4, 5, 6 and 7, characterized by having a lower hemi-cylinder, whose external face presents a series of S-shaped drawings that are distributed along its entire length, schematically corresponding to the fibers of the transversalis fascia and also presenting, the four pairs of larger “S” figures, Petition 870250089937, of 02 / 10 / 2025, page 6 / 7 Page 3 of 3 arranged perpendicularly to the previous ones, forming the inferior epigastric vessels.

9. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2, 3, 4, 5, 6, 7 and 8, characterized by having a circular orifice representing the deep inguinal ring and internally, again presenting the "S" shaped figures in sequence, representing the transversalis fascia and the inner face of the deep inguinal ring, represented by the circular orifice.

10. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to claims 1, 2, 3, 4, 5, 6, 7, 8 and 9, characterized by having, on the lateral wall, in the superior and inferior sections, the inguinal ligament, represented by the serial sequence of “X” and also having a distal circular design, which is completed at the junction of the superior and inferior sections, corresponding to the femoral vein.

11. 3D PRINTED PORTABLE MODEL FOR ANATOMICAL TEACHING OF THE INGUINAL REGION according to the previous claims, characterized by having, on the medial wall of the lower section, two parallel lines along the wall, corresponding to the union of the fibers of the transversus abdominis muscle and the internal oblique muscle, and at the end of which are four "X" shaped drawings, dispersed in two lines, representing the bony thickening of the pubic tubercle. Petition 870250089937, dated 02 / 10 / 2025, page 7 / 7

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