Gantzer muscles are anatomical variations found within the flexor compartment of the forearm. The Gantzer muscle typically arises from the flexor digitorum superficialis (FDS) and inserts into the flexor pollicis longus (FPL) or flexor digitorum profundus (FDP). The presence of this muscle can cause various compressive injuries, including neuropathy of the median or anterior interosseous nerve and impingement of the ulnar, common, or anterior interosseous arteries. Despite its high prevalence, the Gantzer muscle is often excluded from the differential for acute compartment syndrome and should be further considered during treatment and surgical management. This study expanded upon a previous assessment of cadaveric specimen forearms to determine further the prevalence of origin, insertion, and innervation of Gantzer muscles, as well as possible compressions induced from impingement by the anomalous muscle. A total of 288 limbs were dissected in 144 cadavers. The Gantzer muscle was found in 54.6% (148:271) of limbs. Therefore, in general, the Gantzer muscle is more likely to be present than absent. This report also details common and uncommon origins and insertions of Gantzer variants. Support or Funding Information T. Walley Williams Summer Anatomy Research Fellowship; WV Research Challenge Fund [HEPC.dsr.17.06]

This report documents the incidental finding of a horseshoe kidney identified during routine dissection in a gross anatomy course. The anatomic examination demonstrated malrotated bilateral kidneys, which were fused at the inferior poles. Histologic examination revealed no significant pathologic change; however, the fused portion was shown to have an intact cortex and collecting system. Furthermore, the renal vasculature was anomalous with multiple accessory and convoluted arterial vessels. An aortic aneurysm was also noted just superior to the renal fusion. Operative procedures and diagnostic imaging performed in the region of such an anatomical variation may be complicated by unanticipated vascular patterns. Therefore, special attention should be paid to vasculature in the setting of a horseshoe kidney. Support or Funding Information T. Walley Williams Summer Anatomy Research Fellowship;WV Research Challenge Fund [HEPC.dsr.17.06]

The fibularis (peroneus) quartus muscle is a variant muscle located in the lateral leg compartment that, when present, resides posterior to the fibularis longus and brevis muscles. Only found in approximately 11.5% of legs, the fibularis quartus arises from the lower one‐third of the fibula and descends to wrap posteriorly around the lateral malleolus. Confusion in the nomenclature arises due to the variations seen in regards to the distal insertion point of this variant leg muscle. The fibularis quartus can insert into the foot at a variety of locations, leading to many variations in the naming of the subtypes of this muscle. If the fibularis quartus muscle inserts into the retrotrochlear eminence and fibular (peroneal) trochlea of the calcaneus, it is called the fibulocalcaneus externus, which are the most common insertion sites. More distally, the fibularis quartus can insert into the cuboid bone, which is called the fibulocuboideus, though this variant is seen less frequently. Even further into the foot, a variation of the fibularis quartus may insert into the fifth metatarsal of the foot, changing its name to the fibularis digiti minimi (quinti). In this study, we examined the lateral leg compartment to see if a fibularis quartus may be present. In three of 20 legs (15%), a fibularis quartus muscle was identified. The first two examples were the more common fibulocalcaneus externus variant, in that this muscle inserted into the calcaneus. The third example was unique in that its distal tendon split to insert onto the calcaneus as well as the talus bone. The rare example of a fibulotalocalcaneus (peroneotalocalcaneus) muscle has only been reported once previously. This rare variant of the fibularis quartus is only the second known example of this exceedingly rare fibularis quartus variant. This finding is important clinically due to the presence of a fibularis quartus muscle being related to chronic lateral ankle pain and ankle instability. It is also important for radiologists, surgeons, and clinicians to be aware of these lateral leg muscle variants when looking at radiological imaging or in advance of surgical procedures in the lateral leg or foot. Support or Funding Information T. Walley Williams Summer Anatomy Research Fellowship; WV Research Challenge Fund [HEPC.dsr.17.06]; WVU Research Apprenticeship Program (RAP)

The patella is an uncommon site for a tumor. This report details the incidental finding of an excrescence on the right patella identified in a cadaver during a gross anatomy course. Histological assessment revealed no periosteal surface, a very thin cartilage cap, minimal endochondral ossification, bone intermediate to more cartilage, and degenerative changes. The assessment remains unclear. What is clear, however, is that this incidental finding has served as an excellent interdisciplinary exercise for anatomists and pathologists and has benefited the education of undergraduate and graduate medical students. Accordingly, in addition to the gross pathology and histopathology, a workflow is presented. Support or Funding Information T. Walley Williams Summer Anatomy Research Fellowship; WV Research Challenge Fund [HEPC.dsr.17.06]

The fibulocalcaneus (peroneocalcaneus) internus (PCI) muscle is a rare variant leg muscle with a low prevalence of <1%‐3% in cadaveric dissection and imaging studies. The PCI arises from the medial aspect of the distal third of the fibula, descends posterior and lateral to the flexor hallucis longus (FHL) muscle, traverses the tarsal tunnel inferior to the sustentaculum tali of the calcaneus, and inserts into the plantar surface of the calcaneus. However, controversy exists concerning the exact location of the insertion site of the PCI muscle. The insertion of the PCI muscle was recently described as being located distal to the coronoid fossa, a small depression between the anterior tuberosity and the anterior apex of the sustentaculum tali of the calcaneus. However, historical descriptions described the PCI as inserting into either the sustentaculum tali itself or a small tubercle on the medical surface of the calcaneus distal to the sustentaculum tali. During routine dissection of a 53‐year‐old Caucasian male, a PCI muscle was identified, and it inserted into distal to the coronoid fossa on the plantar surface of the calcaneus. More specifically, it inserted into the plantar surface of the calcaneus in the space between the origin of the plantar talonavicular (spring) ligament and the plantar calcaneocuboid ligament. Knowledge of the PCI muscle is important due its involvement with various ankle pathologies, including predisposing individuals to tarsal tunnel syndrome, FHL tenosynovitis, and posterior ankle impingement and pain.