Evaluation of cartilage degeneration in a rat model of rotator cuff tear arthropathy

Abstract

Introduction Rotator cuff tears are the most common injury seen by shoulder surgeons. Many late stage rotator cuff tear patients develop glenohumeral osteoarthritis as a result of torn cuff tendons, termed cuff tear arthropathy. However, the mechanisms of cuff tear arthropathy have not been fully established. It has been hypothesized that a combination of synovial and mechanical factors contribute equally to the development of cuff tear arthropathy. The goal of this study was to assess the utility of this model in investigating cuff-tear arthropathy. Methods We utilized a rat model which accurately reflects rotator cuff muscle degradation after massive rotator cuff tears through either infraspinatus and supraspinatus tenotomy or suprascapular nerve transection. Using a Modified-Mankin Scoring System (MMS), we found significant glenohumeral cartilage damage following both rotator cuff tenotomy and suprascapular nerve transection after only 12 weeks. Results Cartilage degeneration was similar between groups, and was present on both the humeral head and the glenoid. Denervation of the supraspinatus and infraspinatus muscles without opening the joint capsule caused cartilage degeneration similar to that found in the tendon transection group. Conclusions These results suggest that altered mechanical loading after rotator cuff tears is the primary factor in cartilage degeneration after rotator cuff tears. Clinically, understanding the process of cartilage degeneration after rotator cuff injury will help guide treatment decisions in the setting of rotator cuff tears. Level of evidence Basic Science Study, Animal Model

Lose‐Dose Administration of Dexamethasone Is Beneficial in Preventing Secondary Tendon Damage in a Stress‐Deprived Joint Injury Explant Model

“…Secondary joint damage has been implicated in rotator cuff injury and disease as well. In particular, several recent studies have shown damage to the biceps tendon and the glenoid articular cartilage in the weeks following an acute rotator cuff tear in rodent models . Furthermore, high levels of pro‐inflammatory cytokines (interleukin‐1 [IL‐1], interleukin‐6 [IL‐6], and tumor necrosis factor‐α [TNF‐α]) have been measured in human and animal models of acute tendon injury as well as in tendon disease.…”

Rotator cuff tendon assessment using magic‐angle insensitive 3D ultrashort echo time cones magnetization transfer (UTE‐Cones‐MT) imaging and modeling with histological correlation

“…THE ROTATOR CUFF TENDON (RCT) is the primary dynamic stabilizer of the glenohumeral joint . RCT pathology is common, and is present in up to 70% of cases that seek medical attention for shoulder pain .…”

“…T he rotator cuff tendon (RCT) is the primary dynamic stabilizer of the glenohumeral joint. 1 RCT pathology is common, and is present in up to 70% of cases that seek medical attention for shoulder pain. 2 Magnetic resonance imaging (MRI) is widely considered the gold standard for noninvasive evaluation of RCT tearing, but studies have shown low performance for the assessment of RCT tissue quality.…”

Shoulder arthritis secondary to rotator cuff tear: A reproducible murine model and histopathologic scoring system

“…The precise pathophysiology and natural history of joint degeneration in CTA remains poorly understood. RC tendons play a crucial role in maintaining the dynamic stability of the inherently unstable GH joint, so it stands to reason that mechanical forces are the primary cause of articular cartilage degeneration in the setting of a massive RCT . However, loss of mechanical properties does not fully explain the development of CTA, as degeneration and destruction of articular cartilage occurs in <10% of patients with a massive RCT .…”