Research Article Motor-Sparing Neural Ablation with Modified Techniques for Knee Pain: Case Series on Knee Osteoarthritis and Updated Review of the Underlying Anatomy and Available Techniques Tony Kwun-tung Ng , 1,2,3,4 King Hei Stanley Lam , 3,5,6,7,8 and Abdallah El-Sayed Allam 9,10 1 Pain Management Unit, Department of Anaesthesia and Operating Theatre Services, Tuen Mun Hospital, Hong Kong 2 Department of Anaesthesiology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong 3 Center for Regional Anesthesia and Pain Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan 4 Department of Anaesthesia and Intensive Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong 5 Board of Clinical Research, The Hong Kong Institute of Musculoskeletal Medicine, Hong Kong 6 Department of Family Medicine, The Chinese University of Hong Kong, Hong Kong 7 Department of Family Medicine, The University of Hong Kong, Hong Kong 8 Taiwan Association of Prolotherapy and Regenerative Medicine, Taichung, Taiwan 9 Department of Physical Medicine, Rheumatology and Rehabilitation, Tanta University Hospitals and Faculty of Medicine, Tanta University, Egypt 10 Morphological Madrid Research Center (MoMaRC), Madrid, Spain Correspondence should be addressed to King Hei Stanley Lam; drlamkh@gmail.com Received 25 February 2022; Revised 13 April 2022; Accepted 11 May 2022; Published 31 May 2022 Academic Editor: Tatsuo Nakamoto Copyright © 2022 Tony Kwun-tung Ng et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Knee osteoarthritis (KOA) is ubiquitous. However, effective pain managements for patients with grades 3 or 4 KOA for whom conservative treatments are unsuccessful, but for whom surgery is not an option, remain lacking. This case series presented two motor-sparing interventional pain treatment modalities for five such patients. Three of the patients with a mean total WOMAC score of 41 underwent thermal radiofrequency (RF) ablation using a modified motor-sparing approach. One-week and four-week post-RF, the total score dropped to 27 (by 34%) and 19 (dropped 53.7%), respectively. Two other similar patients with a mean total WOMAC score 96 underwent chemical neurolysis using a motor-sparing approach with modified landmarks. The WOMAC score dropped to 58.5 (by 39.1%) and 49 (dropped by 49.0%), one-week and four-week postchemical neurolysis, respectively. A narrative review of the currently available approaches is also provided, with the conclusion that neural ablation using the modified landmarks approach may achieve better pain control and preserve the motor functions for patients with severe KOA for whom conservative treatment was unsuccessful and who are not candidates for surgery. 1. Introduction Knee osteoarthrosis (KOA) is a very common joint disease, with a prevalence ranging from 4.2% to 15.5% and gradually increasing with age [1]. It was ranked 11th among the 291 disabling illnesses worldwide [2]. KOA is associated with diverse causes including age, obesity, metabolic bone dis- eases, and acute or chronic joint injuries [3]. Pain and dis- abilities are the major consequences of KOA, with 25% of patients suffering from severe arthralgia. KOA is believed to be a result of the failure of chondrocytes to maintain homeostasis between the synthesis and degradation of the extracellular matrix and from subchondral bone developing osteoarthrosis [4–8]. The treatment algorithm for KOA starts with noninvasive therapies such as medication, physi- cal therapy, and rehabilitation. Patients in whom good pain Hindawi BioMed Research International Volume 2022, Article ID 2685898, 13 pages https://doi.org/10.1155/2022/2685898