In this report, we describe a rare case of pudendal neuropathy caused by deep-layer penetration of the sacrotuberous ligament (STL), accompanied by perineural venous engorgement, and emphasize its diagnostic and surgical implications. The patient was a 65-year-old man who presented with a 15-year history of left-sided perineal and testicular pain that was markedly exacerbated by sitting and partially relieved by standing or lying down. Pelvic magnetic resonance imaging (MRI) demonstrated asymmetry of the left pudendal nerve, with prominent perineural venous engorgement adjacent to the STL. Conservative treatment failed to provide adequate symptom relief; therefore, transgluteal pudendal nerve decompression was performed. Intraoperatively, the pudendal nerve was found to penetrate the deep layer of the STL and was tightly constricted at the penetration site, with marked venous engorgement. Layer-by-layer release of the deep STL achieved complete neural decompression, followed by gradual collapse of the engorged veins. Postoperatively, the patient experienced immediate and sustained pain relief, with improved tolerance for sitting. Follow-up MRI demonstrated resolution of the venous engorgement and normalization of the perineural soft-tissue signal. In summary, deep-layer penetration of the pudendal nerve through the STL, with associated venous congestion, is rare but clinically significant in pudendal neuropathy. Recognition of this anatomical variant and careful assessment of perineural venous engorgement on MRI may improve diagnostic accuracy and inform layer-by-layer surgical decompression in patients with refractory pudendal neuralgia.

Objective: Posterior interosseous nerve (PIN) syndrome (PINS) is a compressive neuropathy of the deep branch of the radial nerve that primarily presents with motor weakness of finger and thumb extension. Although some patients respond to conservative management, others develop persistent motor deficits requiring surgical decompression. This study aimed to evaluate the clinical outcomes of external neurolysis in patients with PINS presenting with refractory motor weakness. Methods: Seven patients with clinically diagnosed PINS who exhibited persistent motor weakness despite conservative treatment and subsequently underwent surgical decompression were retrospectively reviewed. Clinical characteristics, magnetic resonance imaging (MRI) findings, intraoperative compression sites, and postoperative motor recovery were analyzed. Motor strength was evaluated using the Medical Research Council grading system. Preoperative and postoperative motor strength grades were compared using the Wilcoxon signed-rank test. Results: The patients presented with progressive weakness of finger extension, resulting in impaired hand opening. MRI demonstrated denervation-related signal changes and atrophy in the affected muscles innervated by the PIN. Surgical exploration revealed compressive structures within the radial tunnel, most commonly at the arcade of Frohse. Significant improvement in motor strength was observed within 2 months postoperatively (thumb extension, p = 0.018; second digit extension, p = 0.011; third to fifth digit extension, p = 0.009). One patient experienced symptom recurrence approximately 6 months after the initial surgery and subsequently underwent revision decompression. Conclusion External neurolysis provides meaningful recovery of finger extension in patients with PINS presenting with refractory motor weakness. MRI may support the diagnosis by demonstrating denervation-related morphological changes in the affected muscles. Recurrence of PINS may occur even after initial recovery, highlighting the importance of careful postoperative follow-up.

Objective: : Post-stroke shoulder pain (PSSP) is a common complication that limits the range of motion (ROM) of the shoulder, the patient’s rehabilitation and in turn, affects the patients’ quality of life (QoL). Several treatment modalities such as sling, positioning, strapping, functional electrical stimulation, and nerve block have been suggested in literatures, however none of the treatments had long-term effects for PSSP. In this study, the authors evaluated clinical efficacy of pulsed radiofrequency (PRF) neuromodulation on the suprascapular nerve for PSSP, and suggested it as a potential treatment with long-term effect. Methods: : This retrospective case series was conducted at a single center, a private practice institution. From 2013 to 2021, 13 patients with PSSP underwent PRF neuromodulation of the suprascapular nerve. The primary outcome measure was the Visual analog scale (VAS) score. The secondary outcome measurements included the shoulder ROM, Disability assessment scale (DAS), modified Ashworth scale, modified Rankin scale (mRS), and EuroQol-5 dimension-3L questionnaire (EQ-5D-3L) scores. These parameters were evaluated before PRF modulation, immediately after PRF modulation, and every 3 months until the final follow-up visit. Results: : Six men and seven women were enrolled, and all patients were followed-up for a minimum of 12 months. The mean VAS score was 7.07 points before PRF neuromodulation and 2.38 points immediately post-procedure. Shoulder ROM for abduction and flexion, DAS for pain, mRS, and EQ-5D-3L demonstrated marked improvement. No complications were reported. Conclusion : PRF neuromodulation of the suprascapular nerve is an effective modality in patients with PSSP, and has long-term effect of pain relief, improvement of QoL.

Objective: : We aimed to analyze the effectiveness of external neurolysis on the common peroneal nerve (CPN) in patients with posture-induced compressive peroneal neuropathy (PICPNe). Further, we aimed to examine the utility of magnetic resonance imaging (MRI) in assessing the severity of denervation status and predicting the postoperative prognosis. Methods: : We included 13 patients (eight males and five females) with foot drop who underwent CPN decompression between 2018 and 2020. We designed a grading system for assessing the postoperative functional outcome. Additionally, we performed MRI to evaluate the denervation status of the affected musculature and its effect on postoperative recovery. Results: : The median time to surgery was 3 months. The median preoperative ankle dorsiflexion and eversion grades were both 3, while the average functional grade was 1. Posterior crural intermuscular septum was the most common cause of nerve compression, followed by deep tendinous fascia and anterior crural intermuscular septum. There was a significant postoperative improvement in the median postoperative ankle dorsiflexion and eversion grades and average postoperative functional (4, 5, and 2.38, respectively). Preoperative ankle eversion was significantly correlated with denervation status. Additionally, the devernation status on MRI was positively correlated with the outcome favorability. However, denervation atrophy led to a less favorable outcome. Conclusion : Among patients with intractable PICPNe despite conservative management, surgical intervention could clinically improve motor function and functional ability. Additionally, MRI examination of the affected muscle could help diagnose CPNe and assess the postoperative prognosis.

OBJECTIVE: In Asians, kneeling and squatting are the postures that are most often induce common peroneal neuropathy. However, we could not identify a compatible compression site of the common peroneal nerve (CPN) during hyper-flexion of knees. To evaluate the course of the CPN at the popliteal area related with compressive neuropathy using magnetic resonance imaging (MRI) scans of healthy Koreans.METHODS: 1.5-Tesla knee MRI scans were obtained from enrolled patients and were retrospectively reviewed. The normal populations were divided into two groups according to the anatomical course of the CPN. Type I included subjects with the CPN situated superficial to the lateral gastocnemius muscle (LGCM). Type II included subjects with the CPN between the short head of biceps femoris muscle (SHBFM) and the LGCM. We calculated the thickness of the SHBFM and posterior elongation of this muscle, and the LGCM at the level of femoral condyles. In type II, the length of popliteal tunnel where the CPN passes was measured.RESULTS: The 93 normal subjects were included in this study. The CPN passed through the “popliteal tunnel” formed between the SHBFM and the LGCM in 36 subjects (38.7% type II). The thicknesses of SHBFM and posterior portions of this muscle were statistically significantly increased in type II subjects. The LGCM thickness was comparable in both groups. In 78.8% of the “popliteal tunnel”, a length of 21 mm to < 40 mm was measured.CONCLUSION: In Korean population, the course of the CPN through the “popliteal tunnel” was about 40%, which is higher than the Western results. This anatomical characteristic may be helpful for understanding the mechanism of the CPNe by posture.
Asian Continental Ancestry Group ; Head ; Humans ; Knee ; Magnetic Resonance Imaging ; Nerve Compression Syndromes ; Peroneal Nerve ; Peroneal Neuropathies ; Posture ; Retrospective Studies