Manual therapy should not be on the sideline in the game of treating tendinopathy

ABSTRACT

Tendinopathy is a common but difficult condition to manage in the orthopedic and sports settings. Despite strong evidence supporting exercise and load-management, a substantial proportion of individuals with the condition do not achieve a satisfactory long-term outcome. Tendinopathy can be associated with a number of impairments, including mobility deficits, muscle performance impairments, pain, and possible altered central pain processing – all of which are indications for manual therapy. Manual therapy has not been well described in the management of tendinopathy, even though its indications match the impairments associated with the condition. In this clinical perspective, the role of manual therapy in the management of tendinopathy is explored, with the intention of expanding possible treatment strategies for this challenging condition.

The state of play

Tendinopathy is a common condition seen in the orthopedic and sports settings. While the mechanistic explanation for tendinopathy is multifactorial, tendon pathology often results from repetitive overuse where tissue demand exceeds tissue capacity. To manage excessive demand or reduced capacity, exercise and load modification are the primary interventions in the management of load-induced tendinopathy[1]. However, despite the common nature of tendinopathy and high-quality evidence supporting exercise for its management, a substantial proportion of individuals with tendinopathy fail to achieve positive long-term outcomes [^2–4]. Similarly, a high percentage of persons with tendinopathy are significantly limited in their sport or are unable to return to their sport altogether. To better manage this challenging condition, all therapeutic options should be investigated and considered. Questions should be asked about why are these individuals not getting better? What about our current treatment plan is not successful? What do we do when our star player of exercise is not performing to expectations?

Finding the answers to some of these questions can be difficult, given the complexity of tendinopathy, wide ranging presentations, and ongoing questions about the pathophysiology of the condition. We should also remember tendinopathy is not a condition that can be easily rushed to recovery, and loading progressions may take a long time. However, it is also possible that we are not fully employing our treatment options, particularly in complex, chronic or recalcitrant cases.

Manual therapy is one such process that could help improve the recovery of individuals with tendinopathy. ‘Manual therapy’ refers to a number of skilled hand movements often directed toward soft tissues and joints with numerous physiological effects intended to improve an individual’s current level of function. Given its broad definition and wide-ranging effects, it is important to understand the evidence, or lack thereof, and clinical reasoning behind using manual therapy for various conditions. In this clinical perspective, we explore the role of manual therapy in managing tendinopathy.

Why is manual therapy being left on the sidelines?

Some clinicians have a strong opinion that manual therapy is not a useful intervention. Some label manual therapy as a passive intervention counter to the priority of increasing patient activity levels[5]. Some say evidence does not support the use of manual therapy over other interventions, and time would be better spent with other exercise-based treatments. Perhaps these perceptions are unfounded biases, and perhaps these considerations are legitimate. Nevertheless, current management strategies for tendinopathy are ineffective for a high enough percentage of individuals that additional intervention strategies should be considered and explored. As such, the potential usefulness of manual therapy for tendinopathy should be investigated.

Why we should put manual therapy in the game

In some cases, upwards of 50% of individuals with tendinopathy report a suboptimal long-term outcome [2–4]. Tendinopathy is commonly associated with musculoskeletal impairments throughout the involved limb, activity limitations and participation restrictions. Although patient presentations can be variable, and conflicting evidence exists regarding risk factors, some common physical impairments associated with tendinopathy include localized pain, possible sensory processing impairments, mobility deficits and muscle performance deficits. In each case, manual therapy may be a useful adjunctive treatment to address the impairments associated with tendinopathy (Figure 1). Exercise is appropriate for managing tendinopathy, but in the presence of the above impairments, exercise alone may not be adequate. The implications of each impairment and relevance of integrating manual therapy into the management of tendinopathy will be discussed next.

Figure 1.

Matching manual therapy indications to common tendinopathy examination findings.

Tendinopathy is painful

Pain is the primary complaint of individuals with tendinopathy. Pain will typically be reported as localized to the involved tendon, worsened with tendon loading or after prolonged periods of inactivity. Focal pain aggravated with activity and reduced with rest is typically indicative of a peripheral nociceptive mechanism of pain[6]. Despite its peripheral presentation, some studies have suggested tendinopathy may be associated with altered central pain processing[7]. Upper extremity tendinopathies are commonly associated with signs of sensory processing impairment (e.g. widespread hyperalgesia); however, lower extremity tendinopathies are less consistently linked to altered pain processing[8]. The presence of nervous system sensitization is important because sensitization in tendinopathy may be correlated to worse long term outcomes[9]. While current literature does not suggest poor outcomes are caused by unaddressed nervous system sensitization, it is possible that nociplastic presentations will require more than exercise (or any singular intervention) alone [6,10].

The application of manual therapy to address pain is one of its most common uses by clinicians. Soft tissue mobilization may reduce local inflammatory responses and increased expression of genes associated with tissue repair [11] as well as reducing local levels of substance P [12] which may help to modulate pain locally. A recent rat model of repetitive overuse tasks showed that soft tissue-based manual therapy reduced inflammation and fibrosis of local muscles, tendons and nerves following repetitive grasping tasks[13], and, while this is preclinical in nature, it may suggest a positive effect of pre-exercise manual therapy. Joint-based manual therapy has been shown to not only reduce local muscular and joint inflammation and regional hyperalgesia [14] but can also attenuate flexor withdrawal reflexes in both animal and human studies assessing painful conditions [15–17]. This response may be associated with both segmental spinal inhibition and/or centrally mediated descending inhibition from the brainstem. Joint mobilizations can also improve local and distal pressure pain thresholds and hyperalgesia [18–20]. Together these findings suggest that soft-tissue and joint mobilization, applied either locally or at distant sites, can address peripheral nociceptive processes and also tap into the central nervous system’s ability to reduce local and widespread pain perception via descending modulation. This can help address pain persistence and improve an individual’s tolerance to exercise and activity.

Mobility impairments

Excessive mobility or mobility deficits of joint and soft tissue can contribute to symptoms associated with tendinopathy [21–23]. Biomechanics would suggest that reduced joint or soft tissue excursion may increase strain on the involved tendon when performing a task. When considering the length-tension relationship, muscle and joint restrictions may reduce the capacity to generate passive tension, increasing the need for active muscle recruitment to achieve a given output[24]. To this end, it could be posited that tendinopathy may not resolve as completely as possible if muscle/joint restrictions remain, as the involved tendon may be predisposed to mechanical overload.

While contemporary evidence suggests a specific biomechanical approach of manual therapy is limited and unreliable, the use of manual therapy has been associated with improved range of motion and clinical outcomes [25–27]. Available literature regarding joint mobilization specifically for tendinopathy is limited[28]; however, recent systematic reviews and meta-analyses have shown that soft tissue mobilization, joint mobilization, manipulation and mobilizations with movement can be beneficial in improving mobility in a variety of conditions [29–33]. In the presence of mobility deficits, clinicians could integrate manual therapy into their treatment plan to allow for improved muscle-tendon unit excursion. Through improved mobility, the individual may be able to more appropriately load the involved tendon through its necessary range of motion, allowing for appropriate task/sport specific training.

Muscle performance impairments

Tendinopathy is frequently associated with limited muscle strength and endurance[1]. Tendons need to store and release energy particularly during repetitive activities, and an inability to match task demand could predispose tendons to overuse injury. Impairments in strength may manifest as an inability to perform functional activities or the presence of compensatory movements with dynamic movements such as running or jumping[23]. Clinical and experimentally induced pain can have deleterious effects on static contractions, dynamic contractions, and functional movements [34] and likely plays a role in the muscle performance impairments associated with tendinopathy.

Manual therapy has been associated with improved muscle performance in some cases. Manual therapy techniques may work to increase motor activity through affecting motoneuron pool availability and efferent motor output[35]. Immediate effects of increased muscle output have been reported locally and at remote sites particularly after joint mobilization/manipulation [36–38]. These effects are temporary and do not appear to have any intermediate or long-term carryover. In cases of muscle weakness or pain negatively impacting a progressive loading program, manual therapy may offer a transient period of increased capacity to perform therapeutic exercises to improve motor output. By improving motor output, be it through improving motoneuron availability, decreasing pain or another mechanism, manual therapy techniques may allow the individual to improve performance of functional strengthening programs.

How should manual therapy get in the game?

As previously noted, soft tissue and joint directed manual therapy can be useful in decreasing pain, improving mobility, and improving muscle performance – all of which may be relevant for persons with tendinopathy. Importantly, beyond being a logical intervention, there is some evidence to support manual therapy for tendinopathy [39–43]. Although manual therapy appears to be a rationale intervention for tendinopathy with some supportive evidence, it may be helpful to consider how manual therapy techniques could be applied.

The choice of joint versus soft-tissue directed manual therapy depends on a number of variables, such as patient or therapist preference, clinical examination findings, and intended effect. To date, one tissue-biased technique has not demonstrated greater efficacy than another in studies involving tendinopathy. What is known is the temporal effects of manual therapy are short-lived[44]. If the intent of manual therapy is to improve mobility or decrease pain in order to exercise more effectively, manual therapy should be performed prior to other interventions and reinforced with subsequent activities the individual can perform independently. In this way, pain sensitivity may be reduced or range of motion may be increased, allowing the individual to more actively participate in tendon loading progressions.

While some may disagree, a ‘passive’ intervention does not have to create a passive perception of recovery. Manual therapy has been dubbed as passive, but the intent is to facilitate improved movement through the reduction of pain, improvement of mobility and muscle performance, among a number of other effects[27]. Therefore in the presence of these impairments commonly associated with tendinopathy, the application of manual therapy makes good clinical sense.

Success comes through teamwork

From a research perspective, it is important to determine the discrete effects and mechanisms of interventions in attempts to optimize patient and athlete management. In clinical practice, outcomes are generally better when multiple interventions are combined to address the various impairments limiting function. Manual therapy is not expected to be useful when performed in isolation, just as exercise prescription without education on proper load management or addressing negative psychosocial variables is not clinically sound practice. As previously noted, the indications of manual therapy closely match the physical impairments often associated with tendinopathy (Figure 1). Performing manual therapy to minimize the impact of mobility deficits, decrease pain or improve muscle performance, when necessarily, and then following manual therapy with a proper load progression seems logical.

Despite the reasonable integration of manual therapy given the impairments associated with tendinopathy, there is a limited body of evidence describing its use. A recent narrative review of analgesic effects of joint techniques reported the majority of available evidence describes manual therapy for upper extremity tendinopathies[28]. The lack of robust studies is perhaps a reason why manual therapy is not more commonly suggested for tendinopathy. The lack of studies, but well-matched indications for use, suggest more studies could help guide the role of manual therapy for tendinopathy. However, future studies should determine the effects of integrating manual therapies targeting musculoskeletal impairments with exercise programs in individuals with tendinopathy, and not just the effects of any particular manual therapy approach in isolation.

When it comes to the game of treating tendinopathy, we lose more than we should. Exercise should be our primary player and will manage most problems, but regardless of the loading strategy used, tendinopathy remains a challenging condition to manage. Just one player cannot win the game and manual therapy could be on the field to help. If we plan on continuing to improve patient outcomes, we need to be open to exploring different options than those already strongly supported. Given the positive outcomes in available literature, manual therapy may serve a positive role in the management of tendinopathy, and we should be open to its use.

Biographies

Dhinu Jayaseelan completed his Doctorate in Physical Therapy (DPT) from The George Washington University (GWU) in 2010, fellowship training at the University of Illinois at Chicago in 2014 and is completing his Doctorate in Health Sciences through GWU. Dhinu is an associate professor at the GWU DPT program. He is a board-certified orthopedic clinical specialist and maintains limited clinical practice. He is co-academic director of the Johns Hopkins Hospital & GWU Orthopedic residency, faculty with the Virginia Orthopedic Manual Physical Therapy Institute, and a senior faculty advisor with Maitland Australian Physiotherapy Seminars. He has published numerous peer-reviewed papers, book chapters and monographs in his primary research interest areas of manual therapy and peripheral pain conditions, primarily tendinopathy and patellofemoral pain.

Josiah Sault received his Doctorate in Physical Therapy from Northwestern University in Chicago, Illinois in 2009. He has practiced physical therapy at the University of Illinois Hospital and Health Sciences System since 2010 where he treats a wide variety of patients from acute sports injuries to chronic widespread pain conditions. He completed a post-professional fellowship in orthopedic manual physical therapy in 2014 through the University of Illinois at Chicago (UIC). He has been involved in both the UIC and Northwestern University doctor of physical therapy and fellowship programs and is a program administrator for the Northwestern University Fellowship in Advanced Orthopedic Physical Therapy Practice, Research and Education in Chicago. He has published peer reviewed articles primarily focused on manual therapy interventions for a variety of conditions and co-authored book chapters on manual therapy management of hip and knee disorders. His current interests lie in the physical therapy management of temporomandibular disorders and clinical reasoning and application of manual therapy in orthopedic conditions.

César Fernández-de-las-Peñas received his Degree in Physical Therapy from Universidad Rey Juan Carlos, Spain in 2000. He reached his first PhD degree in Biomedical Sciences in 2007 at the Sensory-Motor Interaction Centre (SMI) in Aalborg University (Denmark) under the supervision of Prof. Lars Arendt-Nielsen. He also finished a second PhD degree in 2008 at the Universidad Rey Juan Carlos. Dr. Fernández-de-las-Peñas works as clinical researcher and teacher at the Universidad Rey Juan Carlos since 2001. He works in private practice specialized in chronic pain from 2000 in Madrid, Spain. He began his career in sport elite players and rheumatology rehabilitation. He has published around 550 peer-reviewed publications. The most relevant topics of his research are headaches, neck pain, lateral epicondylalgia, carpal tunnel syndrome, fibromyalgia syndrome and neuro-physiological effects of manual therapy. His clinical research is mainly concentrated on biomedical sciences within neuroscience. He has participated in 60 conferences with related published proceedings and has given several lectures at national and international meetings.

Funding Statement

The author(s) reported there is no funding associated with the work featured in this article.

Disclosure statement

No potential conflict of interest was reported by the author(s).