The use of elastic therapeutic tape and eccentric exercises for lateral elbow tendinosis: a case series

Abstract

Introduction

‘Lateral elbow tendinosis’ or ‘lateral elbow tendinopathy’ have been suggested to be more appropriate diagnostic terms instead of ‘lateral epicondylitis’ as the condition is degenerative rather than inflammatory. For this reason, it is important that interventions target this degeneration at the common extensor tendon.

Methods

A descriptive, retrospective review of a series of four patients with lateral elbow tendinosis was conducted to examine functional outcomes with the use of elastic therapeutic tape, eccentric exercises and activity modification techniques.

Results

All patients recorded improved changes in pain and grip strength within three months of treatment using elastic therapeutic tape, eccentric exercises and activity modification techniques.

Conclusions

There may be clinical benefit in the use of elastic therapeutic tape, in conjunction with eccentric exercises and activity modification techniques, for the treatment of lateral elbow tendinosis. More rigorous and comprehensive studies are recommended to further investigate this intervention.

Keywords

tendinosis elastic therapeutic tape kinesiotape

Introduction

Lateral elbow pain is a condition that is well-known to pose challenges to the hand therapist due to its long-term recovery, considerable morbidity and financial costs, including time off work and prolonged treatment.¹ The management of this condition revolves primarily around modulating tendon pain, as pain is the primary presenting and limiting factor experienced by this population^2,3 Additional goals of rehabilitative treatment are to maintain movement and strength, and to develop endurance over time to increase function.^4,5 Despite extensive research in this area, there is still no consensus regarding the most clinically effective and/or cost-effective intervention for this condition.

Clinical terminology

‘Lateral epicondylitis’ and ‘tennis elbow’ are common terms used by physicians and therapists when describing the clinical diagnosis related to pain experienced at or around the lateral epicondyle.^6,7 However, research reveals that these terms are misleading. The suffix ‘itis’ implies an inflammatory pathology, but extensive histological immunohistochemical and electron microscopy studies have shown that the condition is degenerative rather than inflammatory.^7–9 This degeneration at the origin of extensor carpi radialis brevis (ECRB) results in an increased presence of fibroblasts, vascular hyperplasia, proteoglycans and glycosaminoglycans together with disorganized and immature collagen which all occur in the absence of inflammatory cells.¹⁰ The clinical and refereed literature indicates that the condition is not inflammatory, the term ‘lateral epicondylitis’ is inappropriate.^6,7

It has been suggested that the more appropriate terms for this condition are either (i) lateral elbow tendinosis or (ii) lateral elbow tendinopathy.⁶ It is important to apply the correct diagnostic terminology since the previous labels for this condition have led to misunderstanding and inappropriate treatment. A shift towards the correct diagnostic terms can ensure the implementation and development of more effective interventions. For the purpose of this article, the term ‘lateral elbow tendinosis’ is used.

Using elastic therapeutic tape for tendinosis

Understanding the pathophysiology of lateral elbow tendinosis may enable better targeting of treatment and rehabilitation efforts.⁴ It is not clear why tendinosis is painful, given the absence of inflammatory cells, nor is it known why collagen fails to mature.^9,11 The true cause of pain may be mechanical discontinuity of collagen fibers or biochemical irritation that results from damaged tendon tissue that activates nociceptors.^2,12 There may also be other potential mechanisms of tendon pain including the involvement of other tissues such as nerves, vessels and bones that are intimately related to tendon.¹²

To date, there has been consensus that the management of tendinosis is through conservative treatment.¹³ Traditionally rest was regarded as an effective intervention for tendinosis, however, there has been a recent move towards early rehabilitation.^4,5,14 Eccentric loading has been shown to assist with tendon rehabilitation by improving collagen alignment and stimulating collagen cross-linkage formation, both of which can improve tensile strength.¹⁵ High-quality systematic reviews by Woodley et al.¹⁵ and Malliaras et al.¹³ examined randomised controlled trials (RCTs) on the effectiveness of eccentric exercises for tendinopathy. Whilst both reported a lack of high-quality RCTs on this topic, the authors stated that eccentric exercises had some positive effect on clinical outcomes such as pain, function, patient satisfaction and return to work compared to concentric exercise, stretching, splinting and ultrasound.

Despite these reported benefits of eccentric exercises, a barrier in conservative management is often the considerable pain reported by patients with elbow tendinosis which directly impacts on their ability to effectively undertake a therapeutic exercise program.¹³ The pain also affects patients’ abilities to engage in many daily functional activities that require elbow movement (such as keyboarding, driving a manual car, lifting objects off a shelf, doing up buttons and handwriting).

Dr Kenzo Kase, the creator of kinesiotape, hypothesized that elastic therapeutic tape may play an assistive role in biomechanically unloading the affected tendon, thereby reducing symptoms and allowing patients to undertake appropriate strengthening exercises.^4,16 As tendinosis results from the degeneration of tendon cells, it is suggested that therapeutic measures to biomechanically correct and unload the tendon (such as with the use of elastic therapeutic tape) may form an important part of therapy.¹⁴ A reported benefit of elastic therapeutic tape is that it can be applied to any injured muscle or joint and there is no restriction to a person’s movement.¹⁷ It is made of tightly woven elasticised cotton fibres which are highly durable and waterproof allowing the tape to be worn for up to a week. Additionally, the tape does not contain any medication or drugs – all the reported benefits come from the tape’s elasticity.¹⁷

The proposed mechanisms of elastic therapeutic tape include: (i) assisting muscle function; (ii) improving circulation of blood and lymph by eliminating tissue fluid or bleeding beneath the skin by moving the muscle; (iii) decreasing pain through neurological suppression and reducing pressure and irritation of chemical receptors by lifting the skin and (iv) enhancing proprioception through increased stimulation to cutaneous mechanoreceptors, thereby reducing pain.¹⁸ By increasing sensory stimulation, the ‘gate control’ theory of pain may also be initiated by interrupting and changing the perception of pain.^18–20

Despite its popularity and reported benefits in clinical practice, there is still relatively little empirical evidence to support the effectiveness of elastic therapeutic tape for injuries, let alone specific musculoskeletal upper extremity disorders.²¹ This study is a descriptive case series of patients with this condition who were treated using elastic therapeutic tape, a new treatment modality, in conjunction with a structured exercise program and activity modification techniques.

This case series was completed by the authors as a preliminary study prior to commencing a blinded randomised controlled trial into the use of elastic therapeutic tape for lateral elbow tendinosis.

Methods

Study design

This descriptive, retrospective review involves four patients who underwent rehabilitation with the use of elastic therapeutic tape for treatment of lateral elbow tendinosis between August 2013 and May 2014.

All patients received application of the tape over varying durations from one to three months. The tape was applied in exactly the same way for each patient (see Figure 1a to d) in conjunction with a standard daily exercise program including heat, stretches, progressive eccentric exercises and the use of compression if needed (see Figure 2a to c). The protocol for rehabilitation treatment was established using therapeutic principles extrapolated from existing and widespread literature on the benefits of eccentric exercises (active contraction and lengthening of a muscle) for lateral elbow tendinosis.^4,13,23 By lengthening the muscle-tendon unit through these exercises, the structure of the tendon can remodel by hypertrophy and increase the tensile strength of the tendon.^4,9

Figure 1.

Application of tape. (a) The elastic therapeutic tape is applied from insertion to origin along the common extensor muscle and then extending proximally up the arm. In this case, the ‘I’ strip is used. The tape extends proximally up the arm as Dr Kase recommends that the length of the ‘I’ strip should be approximately 4 inches above or below the joint to allow better application and to ensure the joint or muscle is taped in the appropriate position.²² (b) The elbow is extended but relaxed and the tape is applied with 25% tension (the distal 1–2 inches of tape is ‘tapered off’ and applied with no tension). (c) The second and third strips of tape are applied as a ‘space correction’ for the area of pain over or around the lateral epicondyle. (d) With the elbow slightly flexed, an ‘I’ or ‘Y’ strip can be used with 25–50% tension with the end of the strip tapered off at no tension. Moderate to full tension may be applied to the middle part of the tape to further reduce tissue movement if required.

Figure 2.

Exercise program. Following their initial appointment, patients completed a home exercise program as follows: (a) Stretching for 30 seconds to 1 minute, twice a day. The focus of stretches is to increase range of motion; however, vigorous stretching must be avoided. Stretching should not reproduce symptoms. (b) Eccentric strengthening exercises once a day. With the elbow bent and the wrist supported, participants will be shown exercises with a 500 g–1 kg weight placed in the hand with the palm facing down (pronation). By supporting the forearm on the edge of a table, the wrist is raised with the unaffected hand (concentric contraction) and lowered slowly for 5 seconds (eccentric contraction). Initial regimen will consist of 1–3 sets of 10 repetitions. Once these strengthening exercises are easily completed, they can increase to 15 repetitions. Weights will only be increased when three sets of 15 repetitions can be completed without difficulty. (c) With the elbow bent by the patient’s side, a broom is held in their hand at the balance point of the broom. The patient then rotates the broom in a slow and controlled motion (four sets of eight repetitions per day). If there is no pain with this exercise, the patient can move their hand 1 cm along the handle (away from the broom head) progressively each day.

Patients were shown how to apply the tape at the initial session and educated on how to monitor for potential side effects, such as skin irritation. Patients were advised that the tape should be worn full-time for 4–7 days before needing to be re-applied (once the tape starts to lift from the skin). Patients were provided with a comprehensive handout on how to re-apply the tape and family members were shown how to apply the tape during the initial session. They were encouraged to use the tape for symptomatic relief and to cease using the tape if or when there were no changes to their symptoms, such as ongoing pain and reduced strength. In this case, all patients continued to use the tape for the duration of treatment (i.e. between one to three months). The application of elastic therapeutic tape was based on the recommended application techniques by Dr Kenzo Kase in ‘Clinical Therapeutic Applications of the Kinesio Taping Method’.²⁴ According to Dr Kase, taping applications for lateral elbow tendinosis can include the ‘Y’ or ‘I’ techniques. In this study, participants had the tape applied using the ‘I’-shaped Rocktape™ along the common extensor muscle (see Figure 2a to c). Prior to the tape application, the skin was cleaned using alcohol wipes to ensure that the skin is free of oils and creams and improve tape adherence. Each patient also received advice on activity modification techniques to reduce symptoms. This included information regarding suggested changes to sporting and work equipment (e.g. such as fitting larger handles on tools/equipment), alternating use of hands so both elbows share the work, keeping elbows close to the body in flexion when applicable, varying activities to minimise repetition, as well as advice on warm-up and cool-down stretches before and after activity/sport.

Participants

The four patients in this study were treated by two hand therapists in Queensland, Australia, between August 2013 and May 2014 for a diagnosis of lateral elbow tendinosis. Two patients were self-referred, one was referred by an orthopaedic surgeon and one referred by a hand surgeon. Of the patients in this study, three were females and one male with their ages ranging from 27 to 52 years (average age being 45 years). Their occupations included labourer, teacher, shop owner and office worker. The labourer and teacher were under Worker’s Compensation Claims whilst the two other patients used private health insurance. Each patient was consistently treated by the same therapist on a weekly to fortnightly basis for the duration of their rehabilitation, which ranged up to three months overall. Each patient was informed of all of his or her rehabilitation options, including no taping or the use of splints or counter-force braces. Informed consent for treatment was given at the initial appointment. All therapy treatment sessions were provided in a private outpatient hand therapy clinic. Details of the specific outcome measures used are reported below.

Clinical presentation

Patients presented to the hand therapy clinic with subjective complaints of pain, weakness and a decreased ability to carry out activities of daily living (ADL) with the affected arm. They all reported pain localised to the lateral epicondyle and pain in the extensor muscles. Provocative tests that confirmed clinical diagnosis in these cases included tenderness when palpating the lateral epicondyle, pain with grip (worse with the elbow extended) and the Thomson manoeuvre, in which pain is elicited by resisted wrist extension with the elbow in full extension and forearm in pronation.²² It should be noted that there are several other provocative tests for lateral elbow tendinosis, such as the Chair test, the Bowden test, Cozen’s test and Mill’s test,²⁵ however, these were not used with these patients. All patients had undergone x-rays of their elbow to rule out other conditions and bone involvement and these tests were normal in all cases. The two patients who were referred by surgeons had undergone ultrasound investigations which confirmed partial tears of the common extensor origin.

History of symptoms ranged from one to six months. All patients remained at work despite their condition; however, the male patient was still on light duties at the time of this study due to the heavy nature of his work as a labourer.

Outcome measures

A subjective assessment was completed to record each patient’s perception of their pain at their initial appointment and at the conclusion of treatment (one to three months post treatment). A Visual Analogue Scale (VAS) was used to evaluate the subjective pain levels of the patients. The VAS has been widely used to assess pain severity by using a 10-cm (100 mm) line with an 11-point scale (0 to 10).^26,27 It is considered a valid and reproducible method of assessing pain, takes little time to complete and allows for cross-cultural comparisons.²⁸ Nevertheless, it is important to note that research also suggests that it is prone to response bias.²⁷ A 13-mm difference in pain scores on the 100-mm VAS is considered the minimum clinically important difference amongst people with various upper limb conditions.²⁹

Objective measurements for grip strength were taken using the Jamar dynamometer which has been shown to have reliability and validity as an outcome measure.^30,31 Mathiowetz et al.³¹ reported high test-retest reliability with the use of the Jamar dynamometer, as well as it having high calibration accuracy. A minimum clinically important difference in grip strength has been reported as being 6.5 kg (19.5%).³² The Jamar dynamometer used in this study to assess the strength of patients is calibrated on a yearly basis to ensure testing accuracy. All participants used the Jamar dynamometer in the standardised position with the elbow flexed, repeated three times and were encouraged to only complete pain-free grip strength. Objective measurements for grip strength were analysed using the contralateral hand grip strength as a control by which improvement was measured. Improvements in grip strength were also compared against stratified normative data in Australia.³³

Results

Descriptive statistics and analyses were used for this study. Complete demographics of patients are presented in Table 1 and outcome measures are presented in Table 2. Overall, positive changes were noted amongst all patients within three months of treatment with the use of elastic therapeutic tape. All patients recorded a decrease in their VAS score signifying a decrease in self-reported pain levels. Changes to pre- and post-VAS scores ranged from 30 mm to 60 mm of difference which is considered a clinically important difference.²⁹ Three patients maintained their full-time work status throughout treatment, whilst one Worker’s Compensation patient continued on light duties.

Table 1.

Demographic Information.

	Age	Gender	Occupation	Insurance	Hand dominance	Affected arm	History of symptoms	Previous assessments/treatment	Duration of rehabilitation	Work status at end of treatment
1	51 years	Female	Office worker (part time)	Private health insurance	Right	Right	>6 months	2 cortisone injections (no reported change) Counterforce brace (no change)	3 months	Full duties
2	50 years	Male	Labourer (full time)	Worker’s Compensation	Right	Right	2 months	– Confirmed tear on USS – 1 cortisone injection (short-term improvement)	3 months	Light duties
3	27 years	Female	Shop owner (full time)	Private health insurance	Right	Right	<3 months	– No previous assessments / other treatments	3 months	Full duties
4	52 years	Female	Teacher (full time)	Worker’s Compensation	Right	Left	1 month	– Confirmed tear on USS – No previous assessments / other treatments	2 months	Full duties

Table 2.

Outcome measures before and after treatment with elastic therapeutic tape.

Patient	Grip strength (before treatment)	Percentile	Grip strength (after treatment)	Percentile	VAS (before treatment)	VAS (after treatment)
1	(R)^a= 8 kg	10th%	(R)^a= 26 kg	40th%	7/10	2/10
1	(L) = 28 kg	90th%	(L) = 28 kg	90th%	7/10	2/10
2	(R)^a= 16 kg	10th%	(R)^a= 46 kg	50th%	7/10	4/10
2	(L) = 38 kg	40th %	(L) = 38 kg	40th%	7/10	4/10
3	(R)^a= 31 kg	50th%	(R)^a= 37 kg	90th%	7/10	1/10
3	(L) = 41 kg	90th%	(L) = 41 kg	90th%	7/10	1/10
4	(L)^a= 19 kg	10th%	(L)^a= 22 kg	40th%	5/10	2/10
4	(R) = 27 kg	50th%	(R) = 30 kg	50th%	5/10	2/10

VAS: Visual Analogue Scale.

Injured arm.

Objective results

Results of outcome measures are presented in Table 2. Grip strength of the injured arm compared to the non-injured arm was reviewed. In all patients, grip strength improved following treatment, ranging from improvements of 3 kg to 30 kg. A minimum clinically important difference in grip strength has been reported as being 6.5 kg (19.5%). Three of the four patients had significant improvements in grip strength. Overall, at the end of treatment, all patients had a grip strength in their affected arm that was in the 40th to 90th percentile for their age group according to stratified normative data in Australia.^33,34

Discussion

This retrospective case series suggests that a rehabilitation program including the use of elastic therapeutic tape and eccentric exercises may be beneficial in treating patients with lateral elbow tendinosis. Data on pain and grip strength obtained from the series of four cases appears to indicate that treatment with elastic therapeutic tape contributed to improvements in the short-term symptoms for all patients.

Although all four participants made significant improvements, patients 1 and 2 (aged 51 and 50 years, respectively) made the greatest improvements in increased strength and improved pain. Both patients 1 and 2 had undergone previous treatment involving cortisone injections and patient 1 had used a counterforce brace. However, both patients reported there were no changes with these interventions prior to commencing treatment with elastic therapeutic tape and an eccentric exercise program. Whilst our results were encouraging, the lack of a control group means that conclusions cannot be drawn on the effectiveness of elastic therapeutic tape, alone or in combination with activity modification and exercise, in treating lateral elbow tendinosis.

Nevertheless, it is still interesting to note that patient 1 reported experiencing symptoms for the longest duration of greater than 6 months, yet reported the greatest improvement in pain (7/10 pre-treatment and 2/10 post-treatment) and grip strength (8 kg to 26 kg). During therapy, all patients also reported that use of the elastic therapeutic tape yielded no adverse side effects and all reported positively on the ease of applicability and wear.

Limitations

The main limitation of this study was the lack of control group and blinded assessment of patients. A randomised controlled trial would have yielded stronger conclusions on the effectiveness of elastic therapeutic tape as opposed to patients who may experience ‘natural recovery’ of their condition/injury.

Additionally, as this study was retrospective, comprehensive pre-therapy measurements were not obtained on all patients. This obviously limits the ability to make conclusive statements and prevents any form of generalising these results to a wider population. Additionally, as this was a case series, there was potential for researcher bias as the primary author knew the participants in the study. A rigorous randomised controlled trial with assessor blinding is therefore recommended, with adequate follow-up to determine longer term functional outcomes of this treatment modality. A design which compares exercise-only to exercise combined with elastic therapeutic tape would also assist in identifying which aspect of treatment has the most impact on key patient outcomes. It is also recommended that patient perception of treatment (i.e. subjective reports on their satisfaction or side effects experienced with use of the tape) be measured concurrently.

Conclusion

The results of this case series study suggest that there may be clinical benefit in the use of elastic therapeutic tape in conjunction with eccentric exercises for the treatment of lateral elbow tendinosis. To date, the goal of managing tendinosis is modulating tendon pain, in conjunction with a focus on therapeutic exercises involving eccentric strengthening. As pain is often a reported barrier for patients undertaking an exercise program, it is proposed that elastic therapeutic tape may assist with reducing pain, thereby allowing exercises to be performed. This study lends preliminary support for the use of elastic therapeutic tape as patients in this study reported no adverse effects, tolerated the wearing regime well and reported ease of application. However, it is evident that more rigorous and comprehensive studies are also recommended to further investigate its effectiveness, specifically adequately powered randomised controlled trials with blinded outcome assessment.

Footnotes

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Conflict of interests

The authors report no conflicts of interest.

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