Neurovascular Compression Caused by Popliteus Muscle Enlargement Without Discrete Trauma

Diagnostic Approach to Lower Limb Entrapment Neuropathies: A Narrative Literature Review

Entrapment neuropathies of the lower limb are a misunderstood and underdiagnosed group of disorders, characterized by pain and dysesthesia, muscular weakness, and specific provoking movements on physical examination. The most frequent of these syndromes encountered in clinical practice are fibular nerve entrapment, proximal tibial neuropathy, sural nerve neuropathy, deep gluteal syndrome or sciatic nerve entrapment, and lateral femoral cutaneous nerve entrapment, also known as meralgia paresthetica. These are commonly mistaken for lumbar plexopathies, radiculopathies, and musculotendinous diseases, which appear even more frequently and have overlapping clinical presentations. A comprehensive anamnesis, physical examination, and electrodiagnostic studies should help clarify the diagnosis. If the diagnosis is still unclear or a secondary cause of entrapment is suspected, magnetic resonance neurography, MRI, or ultrasonography should be conducted to clarify the etiology, rule out other diseases, and confirm the diagnosis. The aim of this narrative review was to help clinicians gain familiarity with this disease, with an increase in diagnostic confidence, leading to early diagnosis of nerve damage and prevention of muscle atrophy. We reviewed the epidemiology, anatomy, pathophysiology, etiology, clinical presentation, and EDX technique and interpretation of the entrapment neuropathies of the lower limb, using articles published from 1970 to 2022 included in the Pubmed, MEDLINE, Cochrane Library, Google Scholar, EMBASE, Web of Science, and Scopus databases.

Nerve and Arterial Supply Pattern of the Popliteus Muscle and Clinical Implications

Introduction. The aim of this study was to investigate the nerve and artery supply and the tibial attachment of the popliteus muscle using anatomical methods. Methods. Forty-four nonembalmed and embalmed extremities were dissected for this study. To measure the attachment area of the popliteus, the most prominent points of the medial epicondyle of the femur and the medial malleolus of the tibia were identified before dissection. A line connecting these two prominent points was used as the reference line, with the most prominent point of the medial epicondyle of the femur as the starting point. This study also investigated the area where the popliteus attaches to the bone and the points where nerves and arteries enter the popliteus muscle when it is divided into three equal parts in the coronal plane. Results. The mean length of the reference line was $34.6\pm 2.1\text{cm}$ . The origin of the popliteus was found to be at a distance of 16.6% to 35.2% on the tibial bone from the proximal region. The popliteus was innervated by only the tibial nerve in 90% of the cases and by the tibial and the sciatic nerves in the remaining 10% of the cases. The inferior medial genicular artery and the posterior tibial artery supplied blood to the popliteus in 90% and 65% of the cases, respectively. When the popliteus muscle was divided into three equal parts in the coronal plane, the nerve and the artery were found to enter the muscle belly in zones II and III and zones I and II in 92% and 98% of the specimens, respectively. Discussion. The anatomical investigation of the popliteus in this study will help identify patients with clinically relevant syndromes.

Macroscopic observations of muscular bundles of accessory iliopsoas muscle as the cause of femoral nerve compression

Compression of the femoral nerve (FN) to the iliac fossa has been reported as a consequence of several pathologies as well as due to the aberrant muscles. The purpose of this research was to investigate the patterns of the accessory muscles of iliopsoas muscles and the relationship of the FN in fifty semi pelvis. Accessory muscular slips from iliacus and psoas, piercing or covering the FN, were found in 19 specimens (7.9%). Based on the macroscopic structure, the muscle was categorized into two types. Pattern 1 as the more frequent variation, was sheet muscular type covering the FN (17 specimens, 89.5%). Pattern 2, the less frequent variation was found on a muscular slip covering the FN (2 specimens, 10.5%). Iliac and psoas muscles and their variants on both types were defined. Appraising the relation between the muscle and the nerves, each disposition of the patterns may be a potential risk for nerve entrapment. The knowledge about the possible variations of the iliopsoas muscle complex and the FN may also give surgeons confidence during pelvic surgery. Recognition of these variations in normal anatomy may be useful to the clinicians when treating patients with refractory leg pain.