Abstract and Introduction
Abstract
Perioperative pain management after knee arthroplasty has undergone a conceptual revolution in the last decade. Along with other exciting innovations, including minimally invasive techniques, computer-assisted procedures and a significant stride in tribology, understanding pain modulation and drug action at a molecular level is recognized as the game changer in arthroplasty surgeries. While most patients usually recover and experience pain relief within 3 mo after TKA, about 20% (10–34%) of the patients are left with an unfavorable long-term pain outcome. Fifty-two percent of patients report moderate pain and 16% report severe pain at rest 30 days after TKA, while pain at movement affects as much as 78% of the patients. Inability to adequately control postoperative pain causes undue suffering, inability to participate in fast-track rehabilitation programs, sleep disturbance (44% patients first 3 nights), delayed discharge, and the development of persistent postsurgical pain. The goal of this review article is to give an overview of the fundamental concept of surgical pain, the molecular mechanism of action of different drugs, evolution of the concept of preventive analgesia, and state of the art for current pain management. When combined and standardized, these factors allow arthroplasty surgeons to offer outpatient arthroplasty procedures.
Introduction
By relieving pain and improving mobility, hip and knee replacement surgeries have successfully alleviated suffering of debilitating conditions such as osteoarthritis, inflammatory arthritis, and avascular necrosis of the femoral head. Improvement in perioperative pain management along with innovations in minimally invasive techniques, computer-assisted procedures, and tribology have improved longevity of the implant and quality of life in patients the world over. Understanding pain modulation and drug action at a molecular level revolutionized postoperative pain management and rehabilitation protocol. Today, most surgeons[1,2] recognize this cultural shift as the game changer in arthroplasty.
While most patients usually recover and experience pain relief within 3 mo after TKA,[3] about 20% (10–34%) of the patients are left with an unfavorable long-term pain outcome. According to Grosu et al.[4] 52% of patients report moderate pain and 16% report severe pain at rest 30 days after TKA, while pain on movement occurs in as many as 78% of patients. Inability to adequately control postoperative pain causes undue suffering, inability to participate in fast-track rehabilitation programs, sleep disturbance (44% patients first 3 nights), delayed discharge, and the development of persistent postoperative pain.[5–7] The unexplained painful TKA without problems related to implants continue to be a challenge for the surgeon[5] (55 of 10) and remain a cause of revision surgery.[8]
The goal of this article is to provide an overview of the fundamental concept of surgical pain, the molecular mechanism of action of different drugs, risk factors for acute and chronic pain, evolution of the concept of preventive analgesia, and finally state of the art current pain management. When combined and standardized, these factors allow arthroplasty surgeons to offer outpatient arthroplasty procedures.[9,10]
Curr Orthop Pract. 2016;27(4):360-370. © 2016 Lippincott Williams & Wilkins
