Rhon D, Teyhen D, Collins G, Bullock G

Abstract submitted to The World Congress of Sports Physical Therapy 2022

Using the same data, compare performance between an injury prediction model categorizing predictors and one that did not, and compare selection of predictors based on univariate significance versus assessing non-linear relationships. Validation and replication of a previously developed injury prediction model in a cohort of 1466 healthy military service members followed for one year after physical performance, medical history, and sociodemographic variables were collected. The original model dichotomized 8 predictors. The second model (M2) kept predictors continuous but assumed linearity, the third model (M3) conducted non-linear transformations. The fourth model (M4) chose predictors the proper way (clinical reasoning and supporting evidence) which led to an addition of 7 additional predictors (15 predictors total), but still kept predictors dichotomized. Model performance was assessed with R2, calibration in the large, calibration slope, and discrimination. Decision curve analyses were performed with risk thresholds from 0.25 to 0.50.

Rhon, D. I., Teyhen, D. S., Collins, G. S., & Bullock, G. S. (2022). Predictive Models for Musculoskeletal Injury Risk: Why statistical Approach Makes All the Difference. BMJ Open Sport & Exercise Medicine. https://doi.org/10.1136/bmjsem-2022-001388

Foster K, Greenlee T, Fraser J, Young J, Rhon D

Investigate the burden of knee, hip, and lumbar spine disorders occurring in the year following an ankle sprain and the influence therapeutic exercise (TE) has on this burden. 33,361 individuals diagnosed with ankle sprain in the Military Health System between 2010 and 2011 were followed for 1 year. Prevalence of knee, hip, and lumbar care-seeking injuries sustained after sprain was identified. Relationships between demographic groups, ankle sprain type, and use of TE with rate of proximal injuries were evaluated using Cox Proportional Hazard Models to determine Hazard Rate effect modification by attribute. Observed impact of TE for ankle sprain on rate of injury to proximal joints was evaluated using Kaplan-Meier survival analyses.

Foster, K. S., Greenlee, T. A., Fraser, J. J., Young, J. L., & Rhon, D. I. (2022). The Influence of Therapeutic Exercise after Ankle Sprain on the Incidence of Subsequent Knee, Hip, and Lumbar Spine Injury. Medicine & Science in Sports & Exercise. https://doi.org/10.1249/MSS.0000000000003035

Foster K, Greenlee T, Young J, Janney C, Rhon D

Posterior tibial tendon dysfunction (PTTD) and tarsal tunnel syndrome (TTS) are debilitating conditions reported to occur after ankle sprain due to their proximity to the ankle complex. The objective of this study was to investigate the incidence of PTTD and TTS in the 2 years following an ankle sprain and which variables are associated with its onset. In total, 22,966 individuals in the Military Health System diagnosed with ankle sprain between 2010 and 2011 were followed for 2 years. The incidence of PTTD and TTS after ankle sprain was identified. Binary logistic regression was used to identify potential demographic or medical history factors associated with PTTD or TTS. In total, 617 (2.7%) received a PTTD diagnosis and 127 (0.6%) received a TTS diagnosis. Active-duty status (odds ratio [OR] 2.18, 95% confidence interval [CI] 1.70-2.79), increasing age (OR 1.03, 95% CI 1.02-1.04), female sex (OR 1.58, 95% CI 1.28-1.95), and if the sprain location was specified by the diagnosis (versus unspecified location) and did not include a fracture contributed to significantly higher (p < 0.001) risk of developing PTTD. Greater age (OR 1.06, 95% CI 1.03-1.09), female sex (OR 2.73, 95% CI 1.74-4.29), history of metabolic syndrome (OR 1.73, 95% CI 1.03-2.89), and active-duty status (OR 2.28, 95% CI 1.38-3.77) also significantly increased the odds of developing TTS, while sustaining a concurrent ankle fracture with the initial ankle sprain (OR 0.45, 95% CI 0.28-0.70) significantly decreased the odds. PTTD and TTS were not common after ankle sprain. However, they still merit consideration as postinjury sequelae, especially in patients with persistent symptoms. Increasing age, type of sprain, female sex, metabolic syndrome, and active-duty status were all significantly associated with the development of one or both subsequent injuries. This work provides normative data for incidence rates of these subsequent injuries and can help increase awareness of these conditions, leading to improved management of refractory ankle sprain injuries

Foster, K. S., Greenlee, T. A., Young, J. L., Janney, C. F., & Rhon, D. I. (2022). How Common is Subsequent Posterior Tibial Tendon Dysfunction or Tarsal Tunnel Syndrome After Ankle Sprain Injury? The Journal of Knee Surgery. https://doi.org/10.1055/s-0042-1751246

Powell J, Sparling T, Yuan X

Globally, 57.7 million people lived with traumatic limb loss in 2017, with the prevalence of amputation in the United States alone expected to reach 3.6 million by 2050. Pain is a common complication after limb loss, with up to 59% of patients experiencing residual limb pain (RLP). Although RLP is often due to a structural etiology, it is difficult to treat, as the exact structure involved is frequently not apparent on history and physical exam alone. This narrative review aims to summarize the available literature on diagnostic ultrasound (US) of the residual limb and examine the utility of US in identifying specific pathology. A total of 31 peer-reviewed manuscripts published between 1989 and 2021 were included, grouped by pathology. While US presents a promising and cost-effective approach to identifying pathology within the residual limb, many gaps remain in the current knowledge, and no specific protocol for a sonographic assessment of the residual limb has ever been proposed. Future studies of diagnostic US of the residual limb should focus on replicable sonographic techniques and standardized exam protocols.

Powell, J. E., Sparling, T. L., & Yuan, X. (2022). Diagnostic Ultrasound of the Residual Limb: A Narrative Review. PM&R. https://doi.org/10.1002/pmrj.12896

Pendlebury G, Rimmert B, Yuan X

Ischiofemoral impingement (IFI) is an uncommon etiology of hip pain, first reported in three patients after total hip arthroplasty and proximal femoral osteotomy. IFI is defined as a narrowing of the ischiofemoral space (IFS) between the lesser trochanter and ischium, leading to edema of the quadratus femoris (QF) muscle and sciatic nerve compression. Abnormalities of the QF may lead to hip, buttock, and groin pain radiating distally from the posterior thigh, likely due to irritation of the sciatic nerve adjacent to the QF.² Existing literature on this condition is limited, including case reports of congenital variants in women and children.³ We report the case of a 50-year-old woman with chronic right hip pain who was diagnosed with ischiofemoral impingement syndrome (IFIS) by physical examination findings and magnetic resonance imaging (MRI) results.

Pendlebury, G., Rimmert, B., & Yuan, X. (2022). Ischiofemoral Impingement Syndrome: Case Report and Treatment Review. Practical Pain Management

Yuan X, Lowder R, Avilles- Wetherell K, Skroce C, Yao K, Soo Hoo J

Rehabilitation is the key to management of patients with subacromial impingement syndrome to prevent disability and loss of function. While point-of-care musculoskeletal ultrasound aids clinical diagnosis of subacromial impingement syndrome, many patients do not demonstrate the classic findings of dynamic supraspinatus tendon impingement beneath the acromion on ultrasound. The objective of this study was to establish the most reliable shoulder ultrasound measurements for subacromial impingement, by evaluating the intra-rater and inter-rater reliability of measurements in asymptomatic participants.

Yuan, X., Lowder, R., Aviles-Wetherell, K., Skroce, C., Yao, K. V., & Soo Hoo, J. (2022). Reliability of point-of-care shoulder ultrasound measurements for subacromial impingement in asymptomatic participants. Frontiers in Rehabilitation Science. https://doi.org/10.3389/fresc.2022.964613

Persinger J and Hager N

The Physical Medicine and Rehabilitation Clinic (PM&R) at Walter Reed National Military Medical Center (WRNMMC) augmented their high frequency ultra-sound systems with an ultra-high frequency ultrasound(UHFUS) system for use in the diagnosing and treatment of musculoskeletal (MSK) and nerve injury warfighters. The Visualsonics VevoMD is an UHFUS system with operating frequencies in the 24–70 MHz range as compared to the typical POC and tertiary care ultrasound systems operating in the15–22 MHz range. Access to this system afforded a unique opportunity to explore the usefulness of this cutting-edge technology in the unique settings of limb loss and multi-trauma in the military.

Persinger, J. E., & Hager, N. (2022). Unique Diagnostic Capabilities and Impact of Ultra-High Frequency Ultrasound in the Musculoskeletal Clinical Setting. Journal of Ultrasound in Medicine. https://doi.org/https://onlinelibrary.wiley.com/doi/epdf/10.1002/jum.16028

Cook C, Zhou L, Bolognesi M, Sheean A, Barlow B, Rhon D

Concomitant cruciate and meniscus injuries of the knee are generally associated with acute trauma and commonly treated with surgical intervention. Comorbidities (simultaneous presence of two or more medical conditions) may be acquired from changes in activity levels and lifestyle after an injury and/or treatment. This study aimed to compare differences in comorbidity proportions between surgical and nonsurgical approaches in Military Health System beneficiaries who had concurrent cruciate and meniscus injuries. The retrospective case control design included 36-month data that were analyzed to reflect 12 months prior to injury/surgery and 24 months after injury/surgery. A comparison of differences within and between groups in surgical and nonsurgical approaches was calculated and logistic regression was used to determine if surgery increased or decreased the odds of comorbidities at 24 months. In our sample of 2,438 individuals with concurrent meniscus and cruciate injury, 79.1% (n¼1,927) received surgical intervention and 20.9% (n¼511) elected for nonoperative management. All comorbidities demonstrated significant within-group differences from pre- to post surgery for those with a surgical intervention; approximately, half the comorbidities increased (i.e., concussion or traumatic brain injury, insomnia, other sleep disorders, anxiety, posttraumatic stress disorder, and tobacco abuse disorder), whereas the other half decreased (i.e., chronic pain, apnea, cardiovascular disease, metabolic syndrome, mental health other, depression, and substance abuse disorders). The odds of acquiring a comorbid diagnosis after surgery reflected the bivariate comparisons with half increasing and half decreasing in odds. To our knowledge, this is the first study to explore comorbidity changes with a control group for individuals with concurrent meniscus and cruciate injuries.

Cook, C. E., Liang, Z., Bolognesi, M., Sheean, A. J., Barlow, B. T., & Rhon, D. I. (2022). Does Surgery for Concomitant Cruciate and Meniscus Injuries Increase or Decrease Subsequent Comorbidities at 2 Years? The Journal of Knee Surgey. https://doi.org/10.1055/s-0042-1750046

Rhon D, Greenlee T, Carreño P, Patzkowski J, and Highland K

Most individuals undergoing elective surgery expect to discontinue opioid use after surgery, but many do not. Modifiable risk factors including psychosocial factors are associated with poor postsurgical outcomes. We wanted to know whether pain catastrophizing is specifically associated with postsurgical opioid and health-care use.

Rhon, D. I., Greenlee, T. A., Carreño, P. K., Patzkowski, J. C., & Highland, K. B. (2022). Pain Catastrophizing Predicts Opioid and Health-Care Utilization After Orthopaedic Surgery A Secondary Analysis of Trial Participants with Spine and Lower-Extremity Disorders. The Journal of Bone and Joint Surgery. https://doi.org/10.2106/JBJS.22.00177

Rhon D and Tucker C

Orthopaedic surgery has revolutionized the expectations for restoration of physical function after musculoskeletal injury and, along with physical therapy, has transformed the limits of recovery. Many orthopaedic procedures have a high success rate for improving quality of life and patient-reported outcomes, yet these procedures carry some level of risk, including postoperative complications. The stepped-care model of health care delivery, when applied to musculoskeletal care, recommends implementing less-intense and lower-risk treatments with known efficacy, such as promotion and education of self-management strategies and physical therapy, before more-invasive and higher-risk treatments such as surgery. This model of managing musculoskeletal disability can improve efficiency of care delivery and reduce medical costs at the health system level. Unfortunately, there is a documented lack of implementing an appropriate course of conservative care, especially physical therapy, prior to surgery across multiple orthopaedic disciplines including sports, spine, and trauma medicine and joint arthroplasty. Failure to respond to nonsurgical treatment has been suggested as a requisite component of the surgical appropriateness criteria, yet practical application can be elusive. Multiple barriers to adequate utilization of conservative treatment exist, including U.S. payment models that increase out-of-pocket expense for patients, negative patient perception of therapy, unreasonable patient expectations from therapy versus surgery, and communication barriers between patient, surgeon, and therapist. Surgeons should ensure that high-quality guidelineappropriate care is delivered early and adequately to their patients. Rehabilitation professionals have a responsibility to deliver high-value care, properly documenting the type and extent of treatment to improve surgical decision-making between surgeons and patients. Criteria to determine appropriateness for surgery should include a standardized and extensive assessment of failed therapies prior to certain elective surgeries. Improved collaboration between surgeons and rehabilitation professionals can result in improved outcomes for patients with musculoskeletal disorders.

Rhon, D. I., & Tucker, C. J. (2022). Nonoperative Care Including Rehabilitation Should Be Considered and Clearly Defined Prior to Elective Orthopaedic Surgery to Maximize Optimal Outcomes. Arthroscopy, Sports Medicine, and Rehabilitation. https://doi.org/10.1016/j.asmr.2021.09.038

Tropf J, Colantonio D, Tucker C, Rhon D

Meniscus injuries occur at a higher rate in the military than the general population. Appropriate management and rehabilitation of meniscus injuries is important for maintaining readiness. The purpose of this study was to describe the health burden of meniscus injuries in the Military Health System (MHS) to identify the surgical intervention rate for meniscus injuries, and to determine which injury characteristics and demographic variables were associated with the likelihood of surgery after injury. The U.S. Department of Defense Management Analysis and Reporting Tool, a database of health care encounters by military personnel and dependents, was queried for encounters associated with a meniscal injury diagnosis between January 1, 2010, and December 31, 2011. Meniscus injuries were categorized into (1) isolated medial, (2) isolated lateral, (3) combined medial and lateral, and (4) unspecified cohorts. Patients under 18 and over 51 years were excluded, as well as patients without records at least 1 year prior to diagnosis or 2 years after. Relevant surgical procedures were identified with the Current Procedural Terminology (CPT) codes for arthroscopic surgery of the knee, meniscus repair, meniscectomy, and anterior cruciate ligament (ACL) reconstruction. There were 2,969 meniscus injuries meeting inclusion criteria during the study period. There were 1,547 (52.1%) isolated medial meniscus injuries, 530 (17.9%) isolated lateral meniscus injuries, 452 (15.3%) involved both menisci, and 435 (14.7%) were unspecified. The mean age was 35.5 years (standard deviation [SD] ¼ 9.3). An adjacent ligamentous injury occurred in 901 patients (30.3%). The treatment course led to arthroscopic surgery in 52.8% (n ¼ 1,568) of all meniscus injuries. Eighty-five percent (n ¼ 385) of combined medial and lateral tears, 54.9% of medial tears, and 51.6% of lateral tears underwent surgery. Partial meniscectomy was the most common procedure performed while 47.2% (n ¼ 1,401) of tears were not treated surgically. Bilateral meniscus injuries had 4.57 greater odds of undergoing knee arthroscopy (95% confidence interval [CI]: 3.46, 6.04), 2.42 times odds of undergoing a meniscus repair, and 4.59 times odds for undergoing a meniscus debridement (95% CI: 3.62, 5.82). The closed nature of the MHS allows reliable capture of surgical rates for meniscus injuries within the military population. Meniscus injuries are common in the military and impose a significant burden on the MHS. Appropriate management and rehabilitation of this injury is important for maintaining readiness.

Tropf, J. G., Colantonio, D. F., Tucker, C. J., & Rhon, D. I. (2022). Epidemiology of Meniscus Injuries in the Military Health System and Predictive Factors for Arthroscopic Surgery. The Journal of Knee Surgery. https://doi.org/10.1055/s-0042-1744189

Rhon D, Kim M, Asche C, Allison S, Allen C, Deyle G

Physical therapy and glucocorticoid injections are initial treatment options for knee osteoarthritis, but available data indicate that most patients receive one or the other, suggesting they may be competing interventions. The initial cost difference for treatment can be substantial, with physical therapy often being more expensive at the outset, and cost-effectiveness analysis can aid patients and clinicians in making decisions. The objective of this study is to investigate the incremental cost-effectiveness between physical therapy and intra-articular glucocorticoid injection as initial treatment strategies for knee osteoarthritis. This economic evaluation is a secondary analysis of a randomized clinical trial performed from October 1, 2012, to May 4, 2017. Health economists were blinded to study outcomes and treatment allocation. A randomized sample of patients seen in primary care and physical therapy clinics with a radiographically confirmed diagnosis of knee osteoarthritis were evaluated from the clinical trial with 96.2% follow-up at 1 year.

Rhon, D., Minchul, K., Asche, C., Allison, S., Allen, C., & Deyle, G. (2022). Cost-effectiveness of Physical Therapy vs Intra-articular Glucocorticoid Injection for Knee Osteoarthritis: A Secondary Analysis From a Randomized Clinical Trial. JAMA Network Open. https://doi.org/10.1001/jamanetworkopen.2021.42709

Rhon D, Oh R, Teyhen D

The DoD has a specific mission that creates unique challenges for the conduct of clinical research. These unique challenges include (1) the fact that medical readiness is the number one priority, (2) understanding the role of military culture, and (3) understanding the highly transient flow of operations. Appropriate engagement with key stakeholders at the point of care, where research activities are executed, can mean the difference between success and failure. These key stakeholders include the beneficiaries of the study intervention (patients), clinicians delivering the care, and the military and clinic leadership of both. Challenges to recruitment into research studies include military training, temporary duty, and deployments that can disrupt availability for participation. Seeking medical care is still stigmatized in some military settings. Uniformed personnel, including clinicians, patients, and leaders, are constantly changing, often relocating every 2-4 years, limiting their ability to support clinical trials in this setting which often take 5-7 years to plan and execute. When relevant stakeholders are constantly changing, keeping them engaged becomes an enduring priority. Military leaders are driven by the ability to meet the demands of the assigned mission (readiness). Command endorsement and support are critical for service members to participate in stakeholder engagement panels or clinical trials offering novel treatments. To translate science into relevant practice within the Military Health System, early engagement with key stakeholders at the point of care and addressing mission-relevant factors is critical for success.

Rhon, D., Oh, R., & Teyhen, D. (2021). Challenges With Engaging Military Stakeholders for Clinical Research at the Point of Care in the U.S. Military Health System. Military Medicine. https://doi.org/10.1093/milmed/usab494

Rhon D, Fraser J, Sorensen J, Greenlee T, Jain T, Cook C

This article was selected by JOSPT’s award committee to receive the 2021 JOSPT Guy G. Simoneau Excellence in Research Award.

The objective of this study was to investigate the influence of time taken to begin musculoskeletal rehabilitation on injury recurrence and one-year ankle-related medical care costs.

Rhon, D., Fraser, J., Sorenson, J., Greenlee, T., Jain, T., & Cook, C. (2021). Delayed Rehabilitation is Associated with Recurrence and Higher Medical Care Use After Ankle Sprain Injuries in the United States Military Health System. Journal of Orthopaedic & Sports Physical Therapy. https://doi.org/10.2519/jospt.2021.10730

Rhon D, Greenlee T, Dickens J, Wright A

Military females sustain higher rates of lower extremity injuries compared to males. This can include intra articular pathology in the hip. Females are considered to have worse outcomes following hip arthroscopy for femoroacetabular impingement and for hip labral repair. To confirm these statements, we queried the current literature.

Rhon, D., Greenlee, T., Dickens, J., & Wright, A. (2021). Are We Able to Determine Differences in Outcomes Between Male and Female Servicemembers Undergoing Hip Arthroscopy? A Systematic Review. Orthopaedic Journal of Sports Medicine. https://doi.org/10.1177/23259671211053034

cook c, sheean a, zhou l, kyong m, rhon d

This study aims to determine whether surgery for cruciate ligament (anterior or posterior) or meniscus injury increased risks of subsequent comorbidities in beneficiaries of the Military Health System. The study was a retrospective case-control design in which individuals with cruciate or meniscus injuries were divided into two groups (surgery or none). Data were pulled 12 months prior and 24 months following each respective event and presence of comorbidities were compared between the two groups. Bivariate analyses and logistic regression were used to determine if surgery increased the odds of comorbidities. Participants included 1,686 with a cruciate ligament injury (30.1% treated surgically) and 13,146 with a meniscus injury (44.4% treated surgically). Bivariate comparisons of surgery versus nonsurgical treatment found multiple significant differences. After adjusting for covariates, a significant (p < 0.05) protective effect was seen only for meniscus surgery for concussion, insomnia, other mental health disorders, depression, and substance abuse. Surgery had no increased/decreased risk of comorbidities for cruciate ligament injuries. For meniscus injuries, surgery demonstrated a protective effect for six of the comorbidities we assessed. The treatment approach (surgery vs. nonsurgical) did not change the risk of comorbidities in those with a cruciate ligament injury. It is noteworthy that three of the six comorbidities involved mental health disorders. Although the study design does not allow for determination of causation, these findings should compel future prospective study designs that could confirm these findings.

Cook CE, Sheean AJ, Zhou L, Min KS, Rhon DI. Does Surgery for Cruciate Ligament and Meniscus Injury Increase the Risk of Comorbidities at 2 Years in the Military System? J Knee Surg. 2023 Apr;36(5):465-474. doi: 10.1055/s-0041-1736197. Epub 2021 Oct 5. PMID: 34610640.

Knotkova H, Hamani C, Sivanesan E, Elgueta Le Beuffe MF, Moon JY, Cohen SP, Huntoon MA

Neuromodulation is an expanding area of pain medicine that incorporates an array of non-invasive, minimally invasive, and surgical electrical therapies. In this Series paper, we focus on spinal cord stimulation (SCS) therapies discussed within the framework of other invasive, minimally invasive, and non-invasive neuromodulation therapies. These therapies include deep brain and motor cortex stimulation, peripheral nerve stimulation, and the non-invasive treatments of repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and transcutaneous electrical nerve stimulation. SCS methods with electrical variables that differ from traditional SCS have been approved. Although methods devoid of paraesthesias (eg, high frequency) should theoretically allow for placebo-controlled trials, few have been done. There is low-to-moderate quality evidence that SCS is superior to reoperation or conventional medical management for failed back surgery syndrome, and conflicting evidence as to the superiority of traditional SCS over sham stimulation or between different SCS modalities. Peripheral nerve stimulation technologies have also undergone rapid development and become less invasive, including many that are placed percutaneously. There is low-to-moderate quality evidence that peripheral nerve stimulation is effective for neuropathic pain in an extremity, low quality evidence that it is effective for back pain with or without leg pain, and conflicting evidence that it can prevent migraines. In the USA and many areas in Europe, deep brain and motor cortex stimulation are not approved for chronic pain, but are used off-label for refractory cases. Overall, there is mixed evidence supporting brain stimulation, with most sham-controlled trials yielding negative findings. Regarding non-invasive modalities, there is moderate quality evidence that repetitive transcranial magnetic stimulation does not provide meaningful benefit for chronic pain in general, but conflicting evidence regarding pain relief for neuropathic pain and headaches. For transcranial direct current stimulation, there is low-quality evidence supporting its benefit for chronic pain, but conflicting evidence regarding a small treatment effect for neuropathic pain and headaches. For transcutaneous electrical nerve stimulation, there is low-quality evidence that it is superior to sham or no treatment for neuropathic pain, but conflicting evidence for non-neuropathic pain. Future research should focus on better evaluating the short-term and long-term effectiveness of all neuromodulation modalities and whether they decrease health-care use, and on refining selection criteria and treatment variables.

Knotkova, H., Hamani, C., Sivanesan, E., Elgueta Le Beuffe, M., Youn Moon, J., Cohen, S., & Huntoon, M. (2021). Neuromodulation for chronic pain. The Lancet. https://doi.org/10.1016/S0140-6736(21)00794-7

Fitzcharles MA, Cohen SP, Clauw DJ, Littlejohn G, Usui C, Häuser W

Nociplastic pain is the semantic term suggested by the international community of pain researchers to describe a third category of pain that is mechanistically distinct from nociceptive pain, which is caused by ongoing inflammation and damage of tissues, and neuropathic pain, which is caused by nerve damage. The mechanisms that underlie this type of pain are not entirely understood, but it is thought that augmented CNS pain and sensory processing and altered pain modulation play prominent roles. The symptoms observed in nociplastic pain include multifocal pain that is more widespread or intense, or both, than would be expected given the amount of identifiable tissue or nerve damage, as well as other CNS-derived symptoms, such as fatigue, sleep, memory, and mood problems. This type of pain can occur in isolation, as often occurs in conditions such as fibromyalgia or tension-type headache, or as part of a mixed-pain state in combination with ongoing nociceptive or neuropathic pain, as might occur in chronic low back pain. It is important to recognize this type of pain, since it will respond to different therapies than nociceptive pain, with a decreased responsiveness to peripherally directed therapies such as anti-inflammatory drugs and opioids, surgery, or injections.

Fitzcharles MA, Cohen SP, Clauw DJ, Littlejohn G, Usui C, Häuser W. (2021). Nociplastic Pain: Towards an Understanding of Prevalent Pain Conditions. The Lancet. https://doi.org/10.1016/S0140-6736(21)00392-5

Cohen S, Vase L, Hooten W

Chronic pain exerts an enormous personal and economic burden, affecting more than 30% of people worldwide according to some studies. Unlike acute pain, which carries survival value, chronic pain might be best considered to be a disease, with treatment (eg, to be active despite the pain) and psychological (eg, pain acceptance and optimism as goals) implications. Pain can be categorized as nociceptive (from tissue injury), neuropathic (from nerve injury), or nociplastic (from a sensitized nervous system), all of which affect work-up and treatment decisions at every level; however, in practice there is considerable overlap in the different types of pain mechanisms within and between patients, so many experts consider pain classification as a continuum. The biopsychosocial model of pain presents physical symptoms as the denouement of a dynamic interaction between biological, psychological, and social factors. Although it is widely known that pain can cause psychological distress and sleep problems, many medical practitioners do not realize that these associations are bidirectional. While predisposing factors and consequences of chronic pain are well known, the flipside is that factors promoting resilience, such as emotional support systems and good health, can promote healing and reduce pain chronification. Quality of life indicators and neuroplastic changes might also be reversible with adequate pain management. Clinical trials and guidelines typically recommend a personalized multimodal, interdisciplinary treatment approach, which might include pharmacotherapy, psychotherapy, integrative treatments, and invasive procedures.

Cohen SP, Vase L, Hooten WM. (2021). Chronic Pain: An Update on Burden, Best Practices, and New Advances. Lancet. https://doi.org/10.1016/S0140-6736(21)00393-7

Knox N, Lee C, Moon J, Cohen S

The objective of this multicenter prospective study was to determine the prevalence and breakdown of pain symptoms among patients with coronavirus disease 2019 (COVID-19) infection admitted for non-pain symptoms and the association between the presence of pain and intensive care unit (ICU) admission and death. Data on the intensity and type of pain were collected on 169 patients with active severe acute respiratory syndrome coronavirus 2 infection at 2 teaching hospitals in the United States and Korea and on 8 patients with acute pain at another large teaching hospital between February 1, 2020, and June 15, 2020. Results showed that acute pain is common during active COVID-19 infection with the most common manifestations being headache, chest pain and spine pain. Individuals without pain were more likely to require intensive care and expire than those with pain. Reasons why pain may be associated with reduced mortality include that an intense systemic stimulus (eg, respiratory distress) might distract pain perception or that the catecholamine surge associated with severe respiratory distress might attenuate nociceptive signaling.

Knox N, Lee C, Moon JY, Cohen SP. (2021). Pain Manifestations of COVID-19 and Their Association with Mortality: A Multicenter Prospective Observational Study. Mayo Clinic Proceedings. https://doi.org/10.1016/j.mayocp.2020.12.014.