Superior Lateral Genicular Nerves Research Articles

The Role of Genicular Radiofrequency Ablation in the Management of Persistent Pain after Total Knee Arthroplasty.

Persistent pain is one of the most frequent complications following total knee arthroplasty (TKA) and can be devastating for the patient's quality of life. The use of genicular nerve radiofrequency ablation (GNRFA) is prevalent regarding non-surgical treatment of knee osteoarthritis. However, it is controversial when employed for the management of residual pain after TKA. This study aims to evaluate the efficacy of GNRFA for the treatment of post-TKA chronic pain and to assess the potential benefits of its use. Twelve patients sustaining chronic pain after TKA underwent GNRFA treatment. The intervention included the superior medial genicular nerve, the superior lateral genicular nerve and the inferior medial genicular nerve. Visual analog scale (VAS) system was utilized for pain assessment at 1-week, 6-month, and 1-year follow-ups. Patients experiencing chronic knee pain derived from other or unspecified causes were excluded. Mean VAS score before the treatment was 8.3, while it ended up 2.3, 5.7, and 7.9 at the 1-week, 6-month, and 1-year follow-up, respectively. Some patients reported residual pain that they regarded more bearable than before the procedure at the 1-week evaluation, with no significant alterations in the 6-month reassessment. In 2 cases results at the 1-week follow-up were dissatisfying, however, this aided us in distinguishing the cause of the persistent pain. We were not able to conclude that GNRFA used for the treatment of chronic pain after TKA is as efficacious as in knee osteoarthritis pain. However, in some cases, it proved to be beneficial regarding discerning the etiology of the pain.

Genicular Nerve Radiofrequency Ablation for the Treatment of Painful Knee Osteoarthritis: Current Evidence and Future Directions.

Genicular nerve radiofrequency ablation (RFA) is increasingly being performed to treat chronic pain due to knee osteoarthritis (KOA). This narrative review provides a concise summary of the relevant neuroanatomy, randomized controlled trials, appropriate patient selection, and safety relating to genicular RFA. Cadaveric studies demonstrate significant variability in the location of the genicular nerves, which has stimulated debate about the ideal target locations for genicular RFA. Despite this, favorable outcomes have been observed in studies targeting only the superior medial genicular nerve, inferior medial genicular nerve, and superior lateral genicular nerve. Several randomized controlled trials demonstrate superiority of genicular RFA compared with intra-articular steroid, viscosupplementation, and oral analgesics. Genicular RFA of the superior medial genicular nerve, inferior medial genicular nerve, and superior lateral genicular nerve appears to be an effective treatment for painful KOA, but targeting additional sensory nerves may further improve treatment success. Although genicular RFA appears relatively safe on the basis of the available data, additional large-scale studies are needed to provide greater confidence.

Validation of a new protocol for ultrasound-guided genicular nerve radiofrequency ablation with accurate anatomical targets: cadaveric study

IntroductionUltrasound (US)-guided radiofrequency ablation (RFA) of genicular nerves (GNs) is increasingly performed to manage chronic knee pain. The anatomical foundations supporting the choice of original targets for US-guided GN-RFA have...

Accuracy of fluoroscopic-guided genicular nerve blockade: a need for revisiting anatomical landmarks

Background and objectivesGenicular nerve blockade (GNB) and radiofrequency ablation (RFA) have recently emerged as treatment options for patients with chronic knee pain. However, an increasing number of anatomical studies and...

Evaluation of the iPACK block injectate spread: a cadaveric study.

Ultrasound-guided infiltration of the interspace between the popliteal artery and capsule of the knee (iPACK) block, a new regional analgesic technique, is believed to relieve posterior knee pain, after total knee arthroplasty, by targeting the articular branches innervating posterior aspect of the joint. The extent of injectate spread and the number of articular branches affected is currently unknown. This cadaveric study aimed to compare the area of dye spread and frequency of articular branches staining following a proximal versus distal injection technique. An ultrasound-guided iPACK injection (10 mL of methylene blue dye solution) was performed in 14 lightly embalmed specimens: 7 injected using a proximal injection technique (1 fingerbreadth above base of patella) and 7 using a distal injection technique (at the superior border of the femoral condyles). Following injection, dissection, digitization, and 3D modeling were performed to map the area of dye spread and determine the frequency of nerve staining. Both injection techniques achieved a similar mean area of injectate spread. Of the four articular branches supplying the posterior knee joint capsule, the genicular branch of posterior division of obturator nerve was stained in all specimens. The proximal injection resulted in staining of superior medial genicular nerve, due to dye spread through the adductor hiatus, whereas superior lateral genicular nerve and anterior branch of common fibular nerve were consistently stained following distal injection. Other articular branches were stained with variable frequency. Both proximal and distal iPACK injection techniques provided a similar area of dye spread in the popliteal region and extensive staining of the articular branches supplying the posterior capsule. The proximal injection technique promoted greater anteromedial dye spread, while the distal injection had more anterolateral spread. Further clinical study is required to confirm our cadaveric findings. .

Localization of the Lateral Retinacular Nerve for Diagnostic and Therapeutic Nerve Block for Lateral Knee Pain: A Cadaveric Study

BackgroundThe lateral retinacular nerve (LRN) is a branch of the superior lateral genicular nerve (SLGN) and is believed to contribute to anterolateral knee pain. The precise anatomical pathway of the LRN, however, has not been demonstrated as it relates to the performance of targeted nerve block procedures. ObjectiveTo describe the anatomical landmarks for localization of the LRN to facilitate diagnostic and therapeutic nerve blocks in the treatment of chronic anterolateral knee pain. DesignDescriptive study. SettingAnatomy dissection laboratory in an academic institution. MethodsTwenty lower extremities were dissected in 12 cadavers. The sciatic nerve was identified, and its branch to the posterior aspect of the knee, the SLGN, was dissected. The SLGN dissection was continued distally to identify its first branch, the LRN. Two measurements were taken from the branch point on the lateral knee deep to the distal biceps tendon in alignment with the fibular head. A validation study completed in 4 knees was performed as follows: 1 mL of colored dye was injected at the first and second measurements. The cadaveric knee was then dissected to assess the accuracy. Main Outcome MeasurementsLocalization of the branch point of the LRN from the SLGN via dissection and then direct assessment of injected dye at the measurement points via dissection. ResultsThe branch point of the LRN from the SLGN was, on average, 5.5 ± 0.66 cm (with a range of 4.5-7.0 cm) proximal to the lateral tibiofemoral joint line in line with the head of the fibula and 2.6 ± 0.62 cm (2.0-4.5 cm) proximal to the tip of the lateral femoral epicondyle. On assessment of the 2 measurements, the measurement 5.5 cm proximal to the lateral joint line accurately targeted the branch point in 100% (4/4) of the knees, whereas the measurement 2.6 cm proximal the tip of the lateral femoral epicondyle accurately targeted the branch point in 75% (3/4) of the knees. ConclusionThe results of this study provide 2 dependable landmarks and a description of the path of the LRN, making it possible to accurately target the LRN to diagnose and alleviate lateral knee pain.