Saphenous Nerve Entrapment Neuropathy After Closed Tibial Fracture: A Case Report

Foot and Ankle Complications after Tibial and Fibular Shaft Fractures

The prevalence of foot and ankle injuries associated with tibial and fibular shaft fractures is estimated to be 25%. A myriad of injury mechanisms and surrounding soft tissue damage related to this type of fracture can lead to distal complications and sequelae in the foot and ankle. Early recognition of concomitant acute injuries and adequate management of delayed complications can optimize the functional outcomes and quality of life in most patients..

Nerve entrapment syndromes of the lower limb: a pictorial review

Peripheral nerves of the lower limb may become entrapped at various points during their anatomical course. While clinical assessment and nerve conduction studies are the mainstay of diagnosis, there are multiple imaging options, specifically ultrasound and magnetic resonance imaging (MRI), which offer important information about the potential cause and location of nerve entrapment that can help guide management. This article overviews the anatomical course of various lower limb nerves, including the sciatic nerve, tibial nerve, medial plantar nerve, lateral plantar nerve, digital nerves, common peroneal nerve, deep peroneal nerve, superficial peroneal nerve, sural nerve, obturator nerve, lateral femoral cutaneous nerve and femoral nerve. The common locations and causes of entrapments for each of the nerves are explained. Common ultrasound and MRI findings of nerve entrapments, direct and indirect, are described, and various examples of the more commonly observed cases of lower limb nerve entrapments are provided.Critical relevance statement This article describes the common sites of lower limb nerve entrapments and their imaging features. It equips radiologists with the knowledge needed to approach the assessment of entrapment neuropathies, which are a critically important cause of pain and functional impairment.Key points• Ultrasound and MRI are commonly used to investigate nerve entrapment syndromes.• Ultrasound findings include nerve hypo-echogenicity, calibre changes and the sonographic Tinel's sign.• MRI findings include increased nerve T2 signal, muscle atrophy and denervation oedema.• Imaging can reveal causative lesions, including scarring, masses and anatomical variants.

Adductor Canal Syndrome After Lesser Trochanter Avulsion Fracture in a 19 Year Old

A rare cause of limb ischemia in young patients, adductor canal syndrome, can be debilitating and result in functional impairment. Diagnosis and treatment may be delayed due to this vascular disease's rarity in young people and because the presenting symptoms can overlap with other more common causes of leg pain in young athletes. Here, authors discuss a young athletic patient with a history of year-long claudication. The patient's reported symptoms, exam findings, and imaging results were consistent with a diagnosis of adductor canal syndrome. This case proved uniquely challenging, given the extent of disease and illustrates potential approach considerations.

Case report: A case of injury to the infrapatellar branch of the saphenous nerve caused by medial approach in knee arthroscopy

We present the case of a 72-year-old man who was referred to our department for treatment of pain on the anteromedial infrapatellar side of the right knee with sensory disturbance that began 2 years earlier. The patient previously underwent right knee arthroscopy at another hospital for a meniscus injury 2 years earlier, which relieved his knee pain, but pain and discomfort near the incision of the medial portal persisted. Given this situation, various physical treatments, such as ice compress, were administered postoperatively. However, the symptom was only partially relieved before discharge. Subsequently, the patient visited two other hospitals and began taking oral pregabalin and duloxetine for treatment of the pain based on a diagnosis of right common peroneal nerve injury. The pain in the same dermatomal distribution was slightly relieved, but a withdrawal reaction was observed. However, the results of an ultrasound at our hospital indicated that the right medial quadriceps femoris tendon showed a hypoechoic area suggesting inflammatory changes. Physical examination of the right knee detected atrophy of the quadriceps femoris muscle, decreased muscle strength (M4), obvious tenderness in the medial side, radiating pain along the anterior tibia, and sensory disturbance (S3+); the results of a drawer test, McMurray test, pivot shift test, and lateral stress test were negative. Based on the aforementioned evidence, a diagnosis was made of injury to the infrapatellar branch of the saphenous nerve, after which neurolysis of the nerve in question was carried out. An enlarged incision was made along the original medial approach. Scar hyperplasia was observed after careful separation of the subcutaneous tissue. During neurolysis, branches were found wrapped in the scar; their continuity and integrity were confirmed after relief. The released nerve was placed in a physiological position. The patient's pain was clearly relieved, and numbness disappeared on the first postoperative day. At 1-month follow-up, all symptoms were found to have resolved.

Downregulation of miR-221-3p by LncRNA TUG1 Promoting the Healing of Closed Tibial Fractures in Mice

Objective

To probe into the effect of LncRNA TUG1 on the healing of closed tibial fracture in mice.

Methods

The closed tibial fracture model of mice was established, selecting the mouse osteoblast line MC3T3-E1, with the cells separated into four groups. The expression levels of TUG1 and miR-221-3p were determined by RT-qPCR analysis, with the targeting relationship between TUG1 and miR-221-3p authenticated by dual luciferase reporter (DLR) assay, detection of cell migration (CM) ability based on Transwell cell migration (TCM) assay, and cell proliferation (CP) acquired by cell counting kit-8 (CCK-8).

Results

Prediction results of the target gene by bioinformatics software showed that miR-221-3p had binding sites with the 3'-UTR of TUG1, and DLR assay authenticated the targeting relationship between LncRNA TUG1 and miR-221-3p. Downregulation of TUG1 inhibited osteoblast CP and CM and promoted osteoblast cell apoptosis (CA). Cell cycle analysis indicated that miR-221-3p provoked cell cycle arrest in G1 stage of MC3T3-E1 cells. The siLncRNA-NC group had higher anticyclin D1 and D3 levels than the siLncRNA TUG1 group, with a lower CA rate in the former, implying that miR-221-3p overexpression inhibited osteoblast CP and CM and LncRNA TUG1 inhibited CA. Downregulation of miR-221-3p partly reversed the retardation out of downregulating TUG1 on osteoblast CP and CM. Bcl-2 level was higher in the LncRNA TUG1 group compared to the siLncRNA TUG1 and miR-221-3p overexpression groups, with remarkably lower SDF-1 level in the miR-221-3p overexpression group than those in the control, miRNA-NC, and LncRNA TUG1 groups.

Conclusion

The downregulation of miR-221-3p by LncRNA TUG1 can promote the healing of closed tibial fractures in mice.