Introduction

Tennis elbow (Lateral epicondylitis) frequently encountered myotendinosis affecting around 3 -5 % of population [1]. It’s an Extensor Carpi Radialis Brevis (ECRB) insertion overuse injury at the lateral epicondyle of humerus affecting dominant arm. Pathogenesis involves angiofibroblastic

hyperplasia or non-inflammatory degeneration of (ECRB) or common extensor origin [2]. Patient presents with pain at the lateral aspect of elbow, decreased grip strength due to pain, tenderness at the lateral epicondyle, Mill’s and Cozen’s test will be positive. Non-operative treatment is successful in 80% of patients with tennis elbow [3]. Treatment involves activity modification, rest, stretching exercises, NSAID, steroid injection [4], extracorporeal shock wave therapy [5], laser treatment [6], botulinum injection [7], arthroscopic debridement [8], acupuncture therapy.

Recent research papers indicate autologous blood injection at the insertion of ECRB proved to be effective in decreasing pain in intermediate and long-term period. The Platelet derived growth factor and transforming growth factor present in blood induce fibroblastic mitosis, trigger stem cells and angiogenesis, probably stimulate production of collagen by tendon sheath fibroblasts [9]. Autologous blood injection is minimal invasive, can be done as outpatient procedure, it has no potential complications like skin atrophy and tendon tears associated with corticosteroid injection [1]. Our purpose is to study the role and efficacy of autologous blood injection in tennis elbow comparing to corticosteroid injection.

Materials and Methods

This was prospective study done from February 2015 to March 2017, involving total 40 (22 male and 18 female) patients of age 21- 39 years. The written informed consent from the patients and institute ethics committee approval taken for the study. All patients who complain of lateral elbow pain with tenderness on lateral epicondyle of humerus and positive Mill’s and cozen’s test enrolled in the study. The detailed history regarding pain, restriction of daily activities, standard elbow antero-posterior and lateral X rays obtained to rule out other pathologies. Patients with typical symptoms of tennis elbow with no previous treatment and normal X ray are included in the study.

Patients were divided in to two groups and patients were allotted to the groups on computer generated table basis.

Group I - methyl prednisolone acetate (40mg) was used along with 1ml of 2% lignocaine solution.

In group I, pre-injection phase mean VAS score was 6.1± 1.5. The pain decreased to a mean VAS of 3.4 ± 0.9 after 4th weeks of steroid injection. The mean VAS at 12 weeks of follow up was 2.1 ± 0.8. Similarly, the Nirschl stage before administration of steroid in Group I was 4.5 ± 1.2. The mean Nirschl stage at 4th week and 12th week follow up was 2.40 ± 0.9 and 1.80 ± 0.6 respectively. (Table 2)

Table 2: Mean VAS score at baseline, 1 week, 4th week and 12th week follow up

NS- Not significant, S- Significant

In group II the mean VAS scores in the pre-injection phase was 6.4± 1.6. The pain decreased to a mean VAS of 4.8 ± 0.8 after 4th weeks of autologous blood injection. The mean VAS at 12 weeks of review was 1.5 ± 0.6. Similarly, the Nirschl stage in Group II was 4.7 ± 1.1 before the use of corticosteroid injection. The mean Nirschl stage at 4th week and 12th week follow up was 2.2 ± 0.6 and 0.9 ± 0.4 respectively.

There is significant difference in P value at 12 weeks between group I and II in both VAS score and Nirschl stage. (Table 2 &3).

Table 3: Mean Nirschl stage at baseline, 1 week, 4th week and 12th week follow up

NS- Not significant, S- Significant

Discussion

Lateral epicondylitis was first described by Runge in 1873 [11]. In a study done by Bishai S.K.et al 5- 10% of tennis players present with lateral epicondylitis [12]. In our series, 56% cases were manual workers, 26% were house wives and 18 % in others mostly in teachers. In spite of various modalities there is no optimal treatment protocol for lateral epicondylitis. Most of the patients (70-80%) get relieved of symptoms within one year, with or without treatment [3].

Logically PRP is more effective than blood due to higher concentration of growth factors per unit volume and also been proved in one clinical trial to be better than autologous blood. Disparity in the efficacy of autologous blood and corticosteroid attributed to the relative difference in the quantity of growth factors delivered to the degenerated tendon However PRP preparation requires specialized equipment which is both expensive and time consuming. Autologous blood injection is easy, does not use any specialized expensive equipment and it can be done on OPD basis.

The mechanism of action of steroid remains unknown. Balasubramaniam et al postulated that the beneficial effects of steroid injection result from the bleeding caused by forcing fluid through tissue planes at high pressures [20].

Conclusion

This study concludes that in treatment of lateral epicondylitis steroid injection gives faster control of pain whereas autologous blood injection gives good long-lasting pain control and improved function. Research with large sample size and longer follow up is required to recommend superiority of autologous blood in treatment of Lateral epicondylitis.

References