The effect of obesity on fatty infiltration of the rotator cuff musculature in patients without rotator cuff tears

Abstract

Background: The modified Goutallier classification system describes the fatty infiltration of rotator cuff musculature (RCM) seen on magnetic resonance imaging (MRI) to assist with surgical decision-making for patients with rotator cuff tears (RCT). We describe the relationship between body mass index (BMI) and fatty infiltration in patients without RCT. Methods: Twenty-five patients from each of four different BMI ranges (< 25 kg/m 2 ; 25 kg/m 2 to 30 kg/m 2 ; 30 kg/m 2 to 35 kg/m 2 ; > 35 kg/m 2) were randomly selected from 1088 consecutive shoulder MRI scans (T1 parasagittal series). Four physician-readers evaluated MRI scans and assigned modified Goutallier grades (0 to 4) in each of the four rotator cuff muscles, as well as two adjacent muscles. Results: Grade distributions varied significantly based on BMI category for infraspinatus (p ¼ 0.001), teres minor (p < 0.001), subscapularis (p ¼ 0.025), teres major (p < 0.001) and deltoid (p < 0.001). Higher grades were evident with a diagnosis of diabetes mellitus in three of six muscles (p < 0.05), hyperlipidaemia in one muscle (p ¼ 0.021) and greater patient age in three muscles (p < 0.05). Conclusions: Obese and severely obese patients without RCT have more fatty infiltration seen on MRI. Patient factors (older age and diagnosis of diabetes mellitus) can be predictive of fatty infiltration in RCM. Fatty infiltration of RCM is not solely attributable to the presence of a RCT.

Biochemical Markers of Aging (Advanced Glycation End Products) and Degeneration Are Increased in Type 3 Rotator Cuff Tendon Stumps With Increased Signal Intensity Changes on MRI

“…14 On the other hand, it has recently been suggested that hyperlipidemia alone may not be a risk factor for retear after rotator cuff surgery. 3,23 In the present study, similar to Ishitani et al, 17 no association was found between Goutallier classification, hyperlipidemia, or tear size and stump classification. In our opinion, stump classification is an assessment of rotator cuff tendon quality, and excessive traction on a degenerated rotator cuff due to fatty degeneration may lead to retear.…”

Rotator Cuff Fibro‐Adipogenic Progenitors Demonstrate Highest Concentration, Proliferative Capacity, and Adipogenic Potential Across Muscle Groups

“…FI, in particular, is a limiting factor that may preclude the option to proceed with repair . In the setting of more global disturbances of muscle structure such the muscular dystrophies or in association with widespread hormonal imbalances such as obesity and diabetes, other muscles can also develop FI . In the case of musculotendinous injuries that orthopedic surgeons more often encounter, the RC has been shown to preferentially develop FI, which suggests there may be intrinsic differences across muscle groups that results in the RC being predisposed to FI .…”

“…Although FI is common in RC tears, this pattern of pathology is not ubiquitous across all types of musculotendinous injuries at all anatomic locations, with the exception of some genetic condition, such as muscular dystrophies, and more global metabolic disturbances such as obesity and type 2 diabetes . Multiple studies have observed high degrees of FI in paraspinal muscles in patients with congenital and degenerative spine diseases .…”

Does statin-treated hyperlipidemia affect rotator cuff healing or muscle fatty infiltration after rotator cuff repair?

“…24 Hyperlipidemia is a recognized risk factor for degenerative rotator cuff tear 1,27 and fatty infiltration of rotator cuff muscles. 30 Deposition of lipid as oxidized low-density lipoprotein forms tendon xanthoma, 24 resulting in altered mechanical properties, chronic inflammation, and impaired circulation, contributing to the pathogenesis of rotator cuff tear and subsequent poor tendon-bone healing after repair. 5,9,28,40 In animal models replicating hyperlipidemia, a greater incidence of poor healing or retear 5,10,14,28 has been reported along with progression of fatty infiltration of the rotator cuff muscles following surgical repair.…”