INTRODUCTION:

Tennis elbow, or lateral epicondylitis, is a common condition that is characterized by pain due to tendinopathy of the common extensor tendon at the lateral epicondyle which is aggravated by resisted muscle contraction of the extensor carpi radialis brevis.^[1] It is usually insidious onset, pre-dominantly at the radio humeral joint and is most prevalent in the working-age population due to strenuous or repetitive overuse activities, that cause significant functional impairment. The prevalence of lateral epicondylitis was 1.3% in the year 2001 and did not differ between men and women.^[5]

The incidence rapidly increases to 19% between 30–60 years of age and seems to be more severe and long-standing in women.^[6] The annual incidence of tennis elbow in general practice is four to seven cases per 1000 patients, with a peak in 35-54 years of age.^[7]

Despite of wide range of conservative therapies available, provide only a short term relief and relapse of symptoms occurs on performing strenuous activity.^[10]Isokinetic eccentric training of the wrist extensors has recently been shown to be effective in treating chronic lateral epicondylitis.^[11] Eccentric exercise strengthening programmes have been emphasised recently as a key element of strength training in rehabilitation. In more recent times, eccentric exercise has been recommended as a part of rehabilitation for other tendonopathies such as patella tendinopathy and lateral epicondylitis.^[12]Studies have shown that isolated eccentric strength training is proved to be effective for treating Achilles^[13], patella^[14] and shoulder tendonopathies. A randomized control trial by Svernlov^[14], conclude that eccentric training is the most effective therapeutic intervention for tennis elbow with regardless of the duration of symptoms. Eccentric exercise can be a key component of tendinopathy rehabilitation if integrated at the appropriate stage of injury. In Tendinopathy rehabilitation Eccentric exercise not only provide structural and functional befefits but also provides neuromuscular benefits through central adaptation of both agonist and antagonist muscles.^[12]Hence the study is undertaken with an attempt to determine the effectiveness of eccentric strengthening of wrist extensors in addition to ultrasound therapy in the treatment of lateral epicondylitis.

METHODOLOGY:

This simple randomized experimental trial was conducted at Saveetha Medical College Hospital in chennai, India. The study was approved by the ethical committee. A sample of 60 subjects diagnosed with chronic lateral epicondylitis was recruited for the study. In this randomized study, 30 patients were assigned to either a control group-A (n=30) receiving standard conventional therapy or an experimental group-B (n=30) that received standard conventional therapy along with eccentric exercise using convenient sampling, with thirty subjects in each group. Patients diagnosed with lateral epicondylitis symptoms for greater than 6 weeks were enrolled for the study. Lateral epicondylitis was diagnosed using the following tests: (1) Pain on palpation at the lateral epicondyle and (2) Cozen’s test (pain on resisted wrist extension). Both male and female subjects between the age of 25 and 40 years were included in the study. Subjects with a history of fracture, dislocation, surgery, bilateral elbow pain, cervical spine pathology, osteoarthritis, or previous steroid injection to the elbow, or previous physical therapy treatment less than 6 weeks prior were excluded from the study. An informed consent was obtained from all subjects before initiation of the study. The subjects were advised to follow the prescribed exercise protocol for lateral epicondylitis. The pre test values for pain and grip strength was recorded and the same was recorded and for post test values at the end of 2 weeks. The pre test and post test values were tabulated and statistically analyzed.

CONTROL GROUP (Group A):

The patient was positioned in sitting position with the affected elbow supported on a pillow. Pulsed ultrasonic therapy was given with a frequency of 1MHz at an intensity of 1.2 W/cm2 for 10 minutes, at the teno-periosteal junction of the ECRB. The treatment session was for 6session/week for a period of 2 weeks.

EXPERIMENTAL GROUP (Group B):

In this group the patients received pulsed ultrasonic therapy as conventional treatment with a frequency of 1MHz and an intensity of 1.2 W/cm2 for 10 minutes, given at the teno-periosteal junction of the ECRB which was then followed by isolated eccentric strengthening exercises of wrist extensors using a Flexbar.

Eccentric Strengthening of Wrist Extensors using Flex-Bar:

The position of the patient was either in sitting or standing whichever is comfortable for the patient. Patient was asked to hold one end of the Flex-Bar in the unaffected hand with the wrist in maximum extension and the other end of the bar with the affected hand. It was then instructed to twist the bar by flexing the unaffected hand while maintaining the wrist of the affected hand in extension. Maintaining this position the patient is then asked to bring the arm in front of the body with both the elbows in extension. While maintain the twist, the unaffected wrist was in full flexion while the affected wrist in full extension. Then the patient was instructed to untwist the bar allowing the affected wrist to move into flexion, i.e, eccentric contraction of the affected wrist extensors. Slow release was instructed for each eccentric wrist extensor contraction which lasted approximately 5 seconds. The subjects performed 15 repetitions of exercise in one set. 3 sets of 15 repetitions were performed for six days of a week for 2 weeks. It takes 5 seconds to complete each repetition and between each set of 15 repetitions there is 30 seconds of rest. Once they could perform the exercises with little or no pain using the level 1 FlexBar, they were progressed with FlexBar with increased resistance, indicating a higher intensity of eccentric resistance.

OUTCOME MEASURE:

The Numerical pain rating scale (NPRS) a widely tool used to measure pain which is a 11-point numeric scale ranges from 0-10 where 0 indicates no pain and 10 indicating worst Pain. Grip strength was measured in a standardized procedure by positioning of the handheld dynamometer. The use of the hand held dynamometer to measure grip strength was illustrated to the subjects prior to testing. The mean of three trials of Maximum grip was recorded and the average was obtained.

RESULT AND STATISTICS:

The collected data was tabulated and analyzed using descriptive and inferential statistics. The pre and post test values for the outcome measures for pain and grip strength were calculated and compared. Parametric statistical tests, dependent t sample test and unpaired t test were used.

Table. 1 Post intervention for pain

S. NO	STATISTICAL MEASUREMENT	EXPERIMENTAL GROUP	CONTROL GROUP
1.	Mean	1.6000	4.1333
2.	Standard deviation	0.56324	0.89955

Fig 1. Post intervention graphical representation for pain

The level of significance by conventional criteria, The level of significance of two-tailed P value is less than 0.0001, this difference is considered to be extremely statistically significant with reduction in pain in the eccentric group than the control group.

Table.2 Post intervention for grip strength

STATISTICAL MEASUREMENT

EXPERIMENTAL GROUP

CONTROL GROUP

Mean

30.8333

17.9000

Standard deviation

7.67927

6.46663

Fig.2 Post intervention graphical representation for grip strength

The level of significance of two-tailed P value is less than 0.0001; this difference is considered to be extremely statistically significant with good improvement of grip strength in the eccentric group than in the conventional group.

DISCUSSION:

Tendinopathies result from overuse resulting in pain on activity, focal tenderness and decreased ability to tolerate tension, leading to reduced functional strength. Though there are many different conservative, surgical or physical therapy approaches for which may produce only temporary relief and reoccurance is relatively possible when repetitive vigorous actions are performed. This is due to to lack of tendon healing in turn leading to poor tensile strength of the tendon leading to functional impairment. Classically, pain in tendinopathy is attributed as a cause of inflammatory processes, but, it has become evident that tendinopathies are not inflammatory but a combination of both, mechanical and biochemical causes. Various research reviews suggested the use of eccentric strengthening exercise as an effective treatment for tendinopathies. Subsequent studies have shown the benefits of using eccentric exercises on Achilles tendon, patellar tendon, proximal lateral elbow and rotator cuff. According to Ohberg L et al eccentric exercise halt the growth of blood vessels in tendinosis and subsequently relieve some of the associated pain.^[30]

There is lack of high‐quality studies with clinically significant results, where no strong conclusions could be made regarding the effectiveness of experimental group when compared with control interventions in relieving pain, improving the grip strength and function status. There are very limited levels of evidence suggesting an increase in function and grip strength using excentric exercises in the treatment of lateral epicondylitis.^[22]But literature has shown promising effect of pain reduction, grip strength improvement and improved functional performance by the use of eccentric exercise as a part of rehabilitation.^[16,17,18]Eccentric exercise should be an integral component of any lateral epicondylalgia rehabilitation program^[19]not only because evidence suggests eccentric work to be superior to conventional interventions but also because of its physiological principles.^[20] Isokinetic, eccentric training has been shown to be an effective treatment, but is also found to be too expensive.

The results of our study are in accordance with the findings of a randomized controlled trial conducted by Roos EM et al in 2004.^[24] He proved that eccentric exercise is more effective in treating tendinosis than splinting. With respect to eccentric training for chronic lateral epicondylitis, Croisier et al compared isokinetic eccentric wrist extensor training to standard physical therapy.^[25] It is claimed that eccentric training results in tendon strengthening by stimulating mechanoreceptors in tenocytes to produce collagen, which is the key cellular mechanism that determines recovery from tendon injuries. In addition, eccentric training may also improve collagen alignment of the tendon and stimulate collagen crosslinkage formation, both of which improve tensile strength.^[26] According to Hampson K et al mechanical conditioning can be used as a treatment for enhancing tendon healing. Tendon responds to mechanical forces by adapting to alterations in the mechanical load being applied.^[27] Svernlov in his study suggested that eccentric training and static stretching for 12 weeks can reduce pain and increase grip strength in lateral epicondylitis.^[15] Repetitive overuse of a muscle results in fatigues where the tendon accepts the kinetic forces been applied, being the cause for tendonopathy injuries Eccentric contraction creates a greater stimulus for the cells of the tendon, producing collagen and resulting in the tendon being able to withstand greater forces. Decreasing neovascularization has been recently documented as another benefit of eccentric strengthening. Each time the degenerative tendon is further worked it restarts the fibroblastic phase of healing laying down new Type III collagen further degenerate the components of a normal tendon. Another reason for positive outcomes could be the increase in tensile strength due to loading induced hypertrophy.^[28]

Evidence suggests that eccentric exercises can be more effective, but must be done with caution due to the common effect of muscle soreness during the initial phase of rehabilitation. Traditional treatment techniques do not directly address the issue of compromised tensile strength. Progressively overloading the tendon overtime through eccentric exercises would gradually lead to an increase in tensile strength progressively.^[29] This progressive overloading is done by Flexbar exerciser which is flexible and durable resistance device. It is an inexpensive rubber bar, which provides a practical means of adding isolated eccentric training by the resistance offered by the bar. It has a rigid surface for enhanced grip during its use. It is used to improve the grip strength and used to improve the upper extremity stabilization by bending, twisting or oscillatory movements. It is of low cost effective treatment that requires no invasive or expensive equipment in the treatment of tennis elbow. A prescription of 3 sets of 15 repetitions daily for approximately 6 weeks appeared to be an effective treatment in the majority of patients.^[21]

Analysis of the results in both the groups showed a statistically significant improvement in NPRS score and Grip strength. Subjects in the experimental group exhibited more substantial benefits in reducing pain and improving grip strength by adding eccentric strengthening exercises to conventional therapy. Moreover this treatment can be performed as part of a home program and does not require continuous medical supervision. In the light of these facts, we can conclude that eccentric exercises using Fexibar when given along with conventional treatment produced promising effects in reducing pain and improving the grip strength among subjects with lateral epicondylitis.

LIMITATIONS AND RECOMMENDATIONS:

A small sample size is the limitation of this study. Investigators in future trials should recruit larger numbers of subjects. No long term follow- up data was collected past 2 weeks; therefore the long-term effects of the interventions of the present study remain unknown. Future research is warranted that would determine the long term effects of the interventions used in this study. We also recommend physical therapists to follow the eccentric exercise protocol for optimal reduction of symptoms among subjects with lateral epicondylitis.

CONCLUSION:

From the result, it was concluded that subjects with lateral epicondylitis elicited more substantial benefits in reducing pain and improving grip strength by adding therapeutic eccentric exercises to standard physical therapy. Thus the findings suggest that therapeutic eccentric exercise should be considered in the management of lateral epicondylitis along with conventional treatment to yield better improvement and thereby prevent the re-occurrence of the condition.

REFERENCES:

1. Timothy F.Tyler, MSPT, ATC, Gregory C.Thomas, DPT,CSCS, Stepen J. Nicholas,MD,Malachy P. Mchugh, PhD, Addition of isolated wrist extensors eccentric exercise to standard treatment for chronic lateral epicondylosis,A prospective randomized trial,J Shoulder Elbow surgery 2010,19,917-922

2. Rajadurai Viswas, RejeeshkumarRamachandran ,PayalKordeAnantkumar,Comparison of Effectiveness of Supervised Exercise Program and Cyriax Physiotherapy in Patients with Tennis Elbow (Lateral Epicondylitis): A Randomized Clinical Trial, The Scientific World JournalVolume 2012, Article ID 939645,doi:10.1100/2012/939645

3. D Stasinopoulos, K Stasinopoulou, M I Johnson , An exercise programme for the management of lateral elbow tendinopathy, Br J Sports Med 2005;39:944–947. doi: 10.1136/bjsm.2005.019836

4. A. P. D’Vaz, A. J. K. Ostor, C. A. Speed, J. R. Jenner, M. Bradley1, A. T. Prevost1 and B. L. Hazleman, Pulsed low-intensity ultrasound therapy for chronic lateral epicondylitis: a randomized controlled trial, Rheumatology 2006;45:566–570 doi:10.1093/rheumatology/kei210

5. Thomas De Smedt, Andy de Jong, Wim Van Leemput, DosscheLieven, Francis Van Glabbeek, Lateral epicondylitis in tennis: update on aetiology, Biomechanics and treatment, Br J Sports Med 2007; 41:816–819. doi: 10.1136/bjsm.2007.036723

6. Alfredson H, Pietilä T, Jonsson P, Lorentzon R,Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis,Am J Sports Med. 1998 May-Jun;26(3):360-6.

7. NynkeSmidt, Danielle AWM van der Windt, Tennis elbow in primary care, 2006,bmj volume 333

8. Jafarian FS, Demneh ES, Tyson SF, The immediate effect of orthotic management on grip strength of patients with lateral epicondylosis,J Orthop Sports PhysTher. 2009 Jun; 39(6):484-9. doi: 10.2519/jospt.2009.2988.

9. Chung B, Wiley JP,Effectiveness of extracorporeal shock wave therapy in the treatment of previously untreated lateral epicondylitis: a randomized controlled trial,Am J Sports Med. 2004 Oct-Nov;32(7):1660-7.

10. Jean-Louis Croisier, Marguerite Foidart-Dessalle, France Tinant, Jean-Michel Crielaard, Be´nedicteForthomme, An isokinetic eccentric programme for the management of chronic lateral epicondylar tendinopathy, Br J Sports Med 2007;41:269–275. doi: 10.1136/bjsm.2006.033324

11. A Binder, G Hodge, A M Green wood, B L Hazleman, D P page thomas,Is therapeutic ultrasound effective in treating soft tissue lesions?British medical journal volume 290 16 February 1985

12. Phil Page, PT, PhD, ATC, CSCS1,A New exercise for tennis elbow that works !,North American Journal of Sports Physical Therapy | Volume 5, Number 3 | September 2010 | Page 189

13. Amelia Williamson, Barbara Hoggart, Pain: a review of three commonly used pain rating scales, Journal of Clinical Nursing 14, 798–804.

14. CR Purdam, P Johnsson, H Alfredson, R Lorentzon, J L Cook, K M Khan, A pilot study of the eccentric decline squat in the management of painful chronic patellar tendinopathy, Br J Sports Med 2004;38:395–397. doi: 10.1136/bjsm.2003.000053

15. Svernlov B, Adolfsson L (2011). Non-operative treatment regime including eccentric training for lateral humeral epicondylalgia. Scandinavian Journal of Medicine and Science in Sports, 11: 328–334.

16. Croisier JL, Foidart-Dessalle M, Tinant F,Crielaard JM, and Forthomme B. An isokinetic eccentric programme for the management of chronic lateral epicondylar tendinopathy. Br J Sports Med 41: 269– 275, 007.

17. Cullinane FL, BoocockMG, and Trevelyan FC. Is eccentric exercise an effective treatment for lateral epicondylitis? A systematic review. Clin Rehabil 28: 3–19, 2014.

18. So¨derberg J, Grooten WJ, and A¨ ng BO. Effects of eccentric training on hand strength in subjects with lateral epicondylalgia: A randomized-controlled trial: Eccentric training and lateral epicondylalgia. Scand J Med Sci Sports 22: 797–803, 2012)

19. Lorenz D. Eccentric exercise interventions for tendinopathies. Strength Cond J 32: 90–98, 2010.),

20. Bisset L, Paungmali A, Vicenzino B, and Beller E. A systematic review and metaanalysisof clinical trials on physical interventions for lateral epicondylalgia. Br J Sports Med 39: 411–422, 2005

21. Timothy F.Tyler, MSPT, ATC, Gregory C.Thomas, DPT,CSCS, Stepen J. Nicholas,MD,Malachy P. Mchugh, PhD, Addition of isolated wrist extensors eccentric exercise to standard treatment for chronic lateral epicondylosis,A prospective randomized trial,J Shoulder Elbow surgery 2010,19,917-922

22. elvanetti A, Barrucci A, Antonaci A. et al The role of eccentric exercise in the functional re‐education of lateral epicondylitis: A randomised controlled clinical trial. (In Italian. ) Med Sport (Roma) 200356103–113.

23. Bisset L, Paungmali A, Vicenzino B. et al A systematic review and meta‐analysis of clinical trials on physical interventions for lateral epicondylalgia. Br J Sports Med 200539411–422.

24. Rees JD, Wolman RL, Wilson A (2009). Eccentric exercises; why do they work, what are the problems and how can we improve them? British Journal of Sports Medicine, 43(4):242‐246.

25. Croisier JL, Foidart-Dessalle M, Tinant F, Crielaard JM, Forthomme B (2007). An isokinetic eccentric programme for the management of chronic lateral epicondylar tendinopathy. British Journal of Sports Medicine, 41:269-75. doi:10.1136/bjsm. 2006.033324

26. Khan KM, Cook JL, Maffulli N, Kannus P (2000). Where is the pain coming from in tendinopathy? It may be biochemical, not only structural, in origin. British Journal of Sports Medicine, 34:81–3.

27. Hampson K, Forsyth NR, El Haj A, Maffulli N (2008). Tendon tissue engineering. Topics in tissue engineering, 4; 1–21.

28. Rees JD, Wolman RL, Wilson A (2009). Eccentric exercises; why do they work, what are the problems and how can we improve them? British Journal of Sports Medicine, 43(4):242‐246.

29. Stanish WD, Curwin S, Mandell S (2000). Tendinitis: its etiology and treatment. New York, Oxford University Press

30. Ohberg L, Lorentzon R, Alfredson H, Neovascularisation in Achilles tendons with painful tendinosis but not in normal tendons: an ultrasonographic investigation. Knee Surgery Sports TraumatolArthrosc 2001; 9:233–8.

Received on 13.07.2018 Modified on 18.09.2018

Research J. Pharm. and Tech 2018; 11(12): 5340-5344.

DOI: 10.5958/0974-360X.2018.00972.1