Evidence for an Environmental and Inherited Predisposition Contributing to the Risk for Global Tendinopathies or Compression Neuropathies in Patients With Rotator Cuff Tears.
BACKGROUND
Rotator cuff tearing has been found to be clinically associated with other tendinopathies and compression neuropathies; a significant excess of these phenotypes has been seen in patients with rotator cuff tears. It is unclear if the association is secondary to environmental or genetic influences.


OBJECTIVE
To examine population-based data for comorbid association of rotator cuff tearing and tendinopathies and compression neuropathies and to determine whether the association extends to relatives of patients with rotator cuff tears, which could suggest a genetic contribution.


METHODS
Cross-sectional study; Level of evidence, 3.


METHODS
The Utah Population Database (UPDB) contains health and genealogical data on over 2 million Utah residents. Current Procedural Terminology, Fourth Revision, codes (CPT 4) and International Classification of Diseases, Ninth Revision, codes (ICD-9) entered in patient records were used to identify patients with rotator cuff tearing and with comorbid tendinopathies and compression neuropathies. We tested the hypothesis of excess familial clustering of these other phenotypes with rotator cuff tearing using a well-established method (estimation of relative risks) in the overall study group of rotator cuff patients (N = 1889).


RESULTS
Significantly elevated risk for elbow, hand/wrist, foot/ankle, knee, and hip tendinopathies, as well as for all tendinopathies and compression neuropathies, was observed in rotator cuff tear cases themselves (P < 2.8e(-13)), in their spouses (P < .02), and in their first-degree relatives (P < 5.5e(-4)). A significant excess of elbow (P = .01), foot/ankle (P = .04), and all tendinopathies (P = 3.1e(-3)) was also observed in second-degree relatives, and a significant excess of compression neuropathies (P = .03) was observed in third-degree relatives.


CONCLUSIONS
The current study shows strong evidence of familial clustering of rotator cuff tearing with other tendinopathies and with compression neuropathy. Observed increased risks in spouses and first-degree relatives supports shared environmental risk factors for rotator cuff tearing, most tendinopathies, and compression neuropathies. Increased risks to third-degree relatives for compression neuropathy suggest an association of these phenotypes that may have a shared genetic etiology.
Department of Orthopaedics, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Robert Z
RZ
Tashjian
Division of Genetic Epidemiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA.
James M
JM
Farnham
Department of Orthopaedics, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Erin K
EK
Granger
Division of Genetic Epidemiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Craig C
CC
Teerlink
Division of Genetic Epidemiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA.; George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, Utah, USA.
Lisa A
LA
Cannon-Albright
compression neuropathy; genetics; rotator cuff; tendinopathy