Electromyography Evaluation of Subscapularis Function After Total Shoulder Arthroplasty - Full Text View

Sponsored by:	Penn State University
Information provided by:	Penn State University
ClinicalTrials.gov Identifier:	NCT00779974

Purpose

The primary objective is to document function of the structurally intact subscapularis after total shoulder arthroplasty by using electromyography. Structural integrity of the subscapularis will be confirmed using ultrasound.

The secondary objective is to determine the diagnostic accuracy of the belly compression and lift off tests in evaluating the integrity and function of the subscapularis when compared to the ultrasound and EMG.

This will be accomplished by enrolling and evaluating patients with a primary diagnosis of osteoarthritis who have had a total shoulder replacement preformed by the PI from September 2003 through December 2007.

Condition	Intervention
Osteoarthritis	Other: Evaluation

Study Type:	Observational
Study Design:	Case-Only, Prospective
Official Title:	Electromyography Evaluation of Subscapularis Function After Total Shoulder

Resource links provided by NLM:

MedlinePlus related topics: Osteoarthritis Ultrasound

U.S. FDA Resources

Further study details as provided by Penn State University:

Primary Outcome Measures:

The primary goal of this study is to document the function of the subscapularis after total shoulder arthroplasty [ Time Frame: end of enrollment ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

The sensitivity and specifity of the belly compression and lift off test will be compared to the results of the ultrasound and EMG [ Time Frame: end of enrollment ] [ Designated as safety issue: No ]

Biospecimen Retention: None Retained

Biospecimen Description:

Estimated Enrollment:	40
Study Start Date:	August 2008
Estimated Study Completion Date:	December 2009
Estimated Primary Completion Date:	November 2009 (Final data collection date for primary outcome measure)

Groups/Cohorts	Assigned Interventions
s/p Total Shoulder Arthroplasty The subject population for this study consists of adult patients with a primary diagnosis of osteoarthritis who have had a total shoulder arthroplasty preformed by the PI between September 2003 through December 2007.	Other: Evaluation For this research study each enrolled subject will have a clinical exam, including range of motion (ROM), and strength testing. The lift off and belly compression tests will be performed. An ultrasound of the shoulder will be done to determine the integrity of the subscapularis tendon. An EMG will be done to determine functionality of the subscapularis.

Detailed Description:

The functional status of the subscapularis following total shoulder arthroplasty has not been well documented.

There is evidence of loss of subscapularis function shown through physical exam in up to 2/3 of patients following total shoulder arthroplasty. [1] Multiple techniques for subscapularis repair have been demonstrated with varying degrees of post operative function, ranging from 11-66% abnormal function on physical exam. [1-3] The belly compression test and the lift off test, which are the main physical exam tests used for evaluation following surgery, are of questionable reliability as indicators of the functionality of the subscapularis. [4,5] Through comparing ultrasound evidence of an intact subscapularis to physical exam findings it has been recognized that the belly compression test has low sensitivity and specificity for subscapularis integrity. [5] Internal rotation is often limited in many postoperative total shoulder patients, which could lead to false positive results. This questions the validity of the outcomes of the studies in which the standard of testing function was through exam.

Ultrasound is a reliable exam for illustration of structural damage to the subscapularis tendon but additional testing is needed to evaluate the function of the structurally intact subscapularis. [5,6] Irreparable changes in the muscle function or nerve denervation could also result in false positive belly compression and lift off tests. The ability to accurately determine the functionality of the subscapularis following total shoulder replacement is imperative to clinic management. Although studies have shown functional abnormalities through physical exam, none have documented the functional status of the subscapularis using objective means such as EMG.

Eligibility

Ages Eligible for Study:	45 Years and older
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No
Sampling Method:	Non-Probability Sample

Study Population

The subject population for this study consists of adult patients with a primary diagnosis of osteoarthritis who have had a total shoulder arthroplasty preformed by the PI between September 2003 through December 2007.

Criteria

Inclusion Criteria:

age >45yrs;
primary diagnosis of osteoarthritis of the shoulder
total shoulder replacement performed by Dr. Armstrong between September 2003 through December 2007.

Exclusion Criteria:

Known contraindications to ultrasound and/or EMG
Inability to provide informed consent
History of recent trauma to the shoulder
Typical shoulder pain
Other suspected shoulder pathology (i.e. tumor, infection)
Pregnancy
Bilateral total shoulder arthroplasty

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00779974

Locations

United States, Pennsylvania
Penn State College of Medicine, Penn State Milton S. Herhsey Medical Center
Hershey, Pennsylvania, United States, 17033

Sponsors and Collaborators

Penn State University

Investigators

Principal Investigator:

April Armstrong, MD

Penn State College of Medicine, Penn State Milton S. Hershey Medical Center

More Information

Publications:

Miller SL, Hazrati Y, Klepps S, Chiang A, Flatow EL. Loss of subscapularis function after total shoulder replacement: A seldom recognized problem. J Shoulder Elbow Surg. 2003 Jan-Feb;12(1):29-34.

Gerber C, Yian EH, Pfirrmann CA, Zumstein MA, Werner CM. Subscapularis muscle function and structure after total shoulder replacement with lesser tuberosity osteotomy and repair. J Bone Joint Surg Am. 2005 Aug;87(8):1739-45.

Ponce BA, Ahluwalia RS, Mazzocca AD, Gobezie RG, Warner JJ, Millett PJ. Biomechanical and clinical evaluation of a novel lesser tuberosity repair technique in total shoulder arthroplasty. J Bone Joint Surg Am. 2005;87 Suppl 2:1-8. No abstract available.

Tokish JM, Decker MJ, Ellis HB, Torry MR, Hawkins RJ. The belly-press test for the physical examination of the subscapularis muscle: electromyographic validation and comparison to the lift-off test. J Shoulder Elbow Surg. 2003 Sep-Oct;12(5):427-30.

Armstrong A, Lashgari C, Teefey S, Menendez J, Yamaguchi K, Galatz LM. Ultrasound evaluation and clinical correlation of subscapularis repair after total shoulder arthroplasty. J Shoulder Elbow Surg. 2006 Sep-Oct;15(5):541-8. Epub 2006 Jul 27.

Sperling JW, Potter HG, Craig EV, Flatow E, Warren RF. Magnetic resonance imaging of painful shoulder arthroplasty. J Shoulder Elbow Surg. 2002 Jul-Aug;11(4):315-21.

Responsible Party:	Penn State College of Medicine, Penn State Milton S. Hershey Medical Center ( April Armstrong, MD )
Study ID Numbers:	IRB#27370
Study First Received:	October 22, 2008
Last Updated:	October 22, 2008
ClinicalTrials.gov Identifier:	NCT00779974 History of Changes
Health Authority:	United States: Institutional Review Board

Keywords provided by Penn State University:

Total Shoulder Arthroplasty
Osteoarthritis

Study placed in the following topic categories:

Musculoskeletal Diseases
Osteoarthritis
Joint Diseases
Arthritis
Rheumatic Diseases

Additional relevant MeSH terms:

Musculoskeletal Diseases
Osteoarthritis
Joint Diseases
Arthritis
Rheumatic Diseases

ClinicalTrials.gov processed this record on September 01, 2009