Comparison of Intra-articular and Intra-tendinous Injections for Treatment of Lateral Epicondylitis

Background Lateral epicondylitis, commonly known as "tennis elbow" is a common cause of elbow
pain, occurring in 1-3% of adults each year. It is a common pathology encountered in primary
care, as well as specialty clinics. The typical patient is in his or her 4th-5th decade.
Males and females are affected equally and the dominant arm is more commonly involved.
Patients participating in sports or work related activities involving repetitive forearm
rotation with the elbow extended are at high risk for developing symptoms. Symptom onset is
insidious and related to repetitive microtrauma, similar to other chronic overuse
tendinopathies. Patients classically present with tenderness over the lateral aspect of the
elbow, just distal and anterior o the lateral epicondyle, at the origins of the extensor
carpi radialis brevis (ECRB) and the extensor digitorum communis (EDC) muscles. Pain is
worsened with resisted wrist and finger extension. 1,2 Much of the information the
investigators have regarding the lateral epicondylitis is from the work of Nirschl and
colleagues. The etiology of lateral epicondylitis is believed to result from small tears of
the ECRB origin from repetitive microtrauma. Gross examination reveals grayish, immature scar
tissue that appears shiny, edematous and friable. Histologic analysis reveals what has been
termed "angiofibroblastic hyperplasia" of the ECRB tendon origin. There are no inflammatory
cells noted on histology, putting into question the classification of lateral epicondylitis
as an inflammatory condition.3-6 Baker et al have noted consistent capsular changes seen on
arthroscopy and developed a classification system, hinting that another source of pain may be
inside the joint.7,8 Early authors described a mass of grayish tissue under the ECRB origin,
intimate with the joint capsule. It may be that this tissue causes capsular inflammation,
leading to elbow pain.9 Although lateral epicondylitis is common, little consensus exists on
the best way to treat it. Historic teaching is that 80% of patients will get better with
non-operative treatments, ranging from relative rest, NSAIDs, bracing and injections. There
will be approximately 4-11% of patients, however, that will require operative treatment
before symptom resolution.1 Current mainstays of treatment are non-operative. Many patients
do get better with rest and activity avoidance. Counterforce braces do not lead to quicker
recovery, however, they do allow for more forceful activity during that recovery period.10
NSAIDs have not shown added benefit long term either.1,2 There has been significant interest
in the efficacy of injections in treatment of both acute and chronic lateral epicondylitis.
Steroid injections have been used as standard treatment for decades. Anecdotally, patients do
well with injections. Recent large, prospective, randomized studies have shown minor
improvements in the short term, but no long term benefits when compared to saline
injection.11-15 Protocols for these studies varied greatly, both in steroid utilized and
injection technique. Common injection techniques included injecting at the point of maximal
tenderness versus at the ECRB origin. Additionally, some authors injected a single time,
whereas others used a peppering technique, with one skin entry point and multiple entry
points in the muscle. Consistently, however, no intra-articular injections were reported. The
investigator suspect that elbow joint inflammation may be an underappreciated source of pain
in lateral epicondylitis. Our hypothesis is that patients receiving intra-articular
injections will have greater improvement compared to patients receiving either no injection
or an intra-tendinous injection.

Statement of Objectives

1. To directly compare outcomes of patients with lateral epicondylitis who receive one of
three treatment options: 1. physical therapy and rest 2. physical therapy and
intra-tendinous corticosteroid injection or 3. physical therapy and intra-articular
corticosteroid injection.

2. To blind both patient and assessing physician/nurse research coordinator to the
treatment that was received for the duration of the study, in order to reduce the effect
of any potential bias.

3. To collect outcome data, both subjectively from the patient using proven outcome
measures, and objectively from regularly spaced follow up visits with blinded assessors.

4. To collect and comment on data from the three treatment groups regarding outcomes
related to pain scores, functional outcomes and recurrence of symptoms.

Materials & Methods This will be a randomized, double-blind, controlled trial comparing
patients who receive physical therapy and rest, physical therapy and intra-tendinous
corticosteroid injection or physical therapy and intra-articular corticosteroid injection for
the treatment of lateral epicondylitis. To our knowledge there are no level I or II studies
evaluating intra-articular elbow injections in the literature. All patients will be treated
at one hospital system at one of 2 locations Truman Medical Center-Hospital Hill (TMC-HH) or
Truman Medical Center- Lakewood (TMC-LW), by the principal investigator Our goal is to enroll
patients who are seeking care from either a primary care sports medicine physician or
orthopaedic surgeon for their persistent and limiting elbow pain. Potential subjects who meet
inclusion criteria will be approached about participating in the study. Enrollment will
continue until sufficient numbers have been reached to determine a significant difference.
Based on our power analysis a total of 82 patients will be enrolled in the study.

Lateral epicondylitis is a clinical diagnosis.1,2 In our patients, diagnosis will be made
based on a thorough history and physical examination. Patients with lateral epicondylitis are
typically present in the 4th or 5th decade of life with vague, lateral elbow pain. The pain
is of insidious onset without a singular inciting event. Symptoms are typically in the
dominant arm and occur in patients that perform activities involving repeated wrist extension
against resistance. Patients typically do not have mechanical symptoms as is seen with loose
bodies or osteochondral lesions. Neurologic deficits or alterations are not seen with this
condition. Systemic inflammatory diagnoses, such as rheumatoid arthritis or systemic lupus
erythematosus can have widespread vague joint pains that can confound the diagnosis of
lateral elbow pain. Patients with these conditions will be excluded.

On physical examination, patients will have tenderness about the lateral elbow, typically at
the origin of the ECRB tendon just distal to the lateral epicondyle. This pain will be
exacerbated by resisted extension of the wrist, and/or resisted extension of the long finger.
In rare cases elbow ROM will be limited. Standard elbow radiographs will be obtained to rule
out fracture, arthritis, intra-articular loose body, deformity, osteonecrosis, osteochondral
lesion, neoplasm and subtle instability. Posterolateral rotatory instability (PLRI) of the
elbow is another source of lateral elbow pain, and posterolateral drawer testing will be
performed on all patients to rule out this condition. Although cubital tunnel syndrome
typically causes medial elbow pain, it can present with non-focal, vague pain. A combination
of a thorough neurologic exam of the distal extremity along with compression of the cubital
tunnel and presence or absence of a Tinel's sign at the elbow will be used to diagnosis the
presence of this condition. Patients who have concern for shoulder or wrist pathology or
cervical spine pathology will be excluded from the study.

Inclusion Criteria:

- Confirmed diagnosis of lateral epicondylitis based on 2 or more of the following
diagnostic criteria: tenderness over the lateral epicondyle; pain with resisted wrist
extension; pain with resisted long finger extension.

- Symptoms lasting a minimum of 6 weeks

- Pain score of >= 3/10 using the Visual Analog Scale (VAS)

- Age >= 18 years

Exclusion Criteria:

- History of prior elbow surgery

- History elbow fracture within the past year

- Elbow instability on physical examination

- Elbow arthritis on radiographs

- Compressive neuropathy in the affected extremity (i.e.carpal tunnel, cubital tunnel)

- Evidence of cervical myelopathy, radiculopathy or brachial plexopathy

- History of systemic inflammatory condition (i.e. rheumatoid arthritis or systemic
lupus erythematosus)

- Allergy to study administered medications (steroid or lidocaine)

- Neoplasm

- Non-English speaking patients

- Inability to comply with study protocols and follow up.

- Pregnant female