Science continues to examine interventions to improve fitness, delay age-related decrements in physical function and facilitate healing and recovery after injury. These factors, or lack thereof, directly affect not only quality of life, but also the overall health care financial burden. With a surging population of seniors 65 years and older, which will swell to over 98 million by 2060, the need for interventions that may mitigate senescent changes could not be timelier. Orthopedic surgeons face many challenges in providing care to not only an aging population, but also to a younger subset that is highly active and engaged in a variety of high-impact sports. Therefore, interventions that can positively affect patient health-related outcomes from the time of injury throughout the rehabilitation process are highly warranted.
This special issue will examine a novel but increasingly popular intervention, blood flow restriction (BFR) training. BFR training utilizes an automated pressure cuff placed on the proximal limbs to restrict blood flow and, when combined with light resistance exercise, produces a variety of positive physiological effects. BFR shows potential as an adjunct strategy postinjury or surgery to improve general physical conditioning, target muscle weakness around affected joints and hasten recovery. Moreover, BFR may also benefit the geriatric patient by mitigating age-related decrements in physical function. The following 6 articles will provide the reader with important information about the science, safety, and implementation of BFR training.
From a health and safety perspective, Dr Loenneke and colleagues provide a thorough review of the mechanisms and science behind BFR training. Although the mechanisms are not fully understood, this paper serves as a well-crafted summary on current best evidence for the adaptations being seen via BFR. Similarly, Dr Cahalin and colleagues have expanded the review on safety to higher risk patients with hypertension. With the aging baby boomer population likely to continue to seek orthopedic care, this article describes what is currently published and the scientific understanding of applying BFR in the hypertensive patient.
A primary concern during periods of disuse is the ensuing muscle atrophy that occurs. Dr Lambert and colleagues describe the potential ability of BFR to upregulate muscle protein metabolism and anabolic signaling to slow or reverse the catabolic postsurgery/injury state. Dr Hackney and colleagues discuss BFR as an intervention to mitigate age-related muscle loss (sarcopenia) and strength (dynapenia) within an aging population that can be implemented both preoperatively and postoperatively to hasten recovery following orthopedic procedures.
Anterior cruciate ligament (ACL) reconstruction is a common orthopedic surgery. Dr Patterson and colleagues describe the application of BFR after ACL reconstruction. There are currently multiple clinical trials worldwide assessing the addition of BFR to ACL rehabilitation. This paper describes the rationale for the addition of BFR postsurgically, the state of the current evidence and a sample clinical protocol. Finally, Dr Bradner and colleagues have provided a thorough review on the reported side effects and safety of BFR.
As this technique becomes more widespread, it is important for clinicians to understand the current applications, limitations, and safety considerations in order to effectively apply this modality to appropriate patients. Finally, we would like to thank all the authors for their time and contributions to this symposium.