Clin Should Elbow.  2024 Dec;27(4):419-427. 10.5397/cise.2024.00416.

Anterolateral rotatory instability of the elbow: a possible etiology of primary osteoarthritis

• Kim YB
• Fitzsimmons JS
• Bellato E
• O’Driscoll SW
• Jang HS
• Kim DW

• KMID: 2563640
• DOI: http://doi.org/10.5397/cise.2024.00416

Abstract

Background
The purpose of this study is to describe anterolateral rotatory instability (ALRI) as a possible etiology of primary osteoarthritis (OA) of the elbow.
Methods
We examined 76 fresh frozen cadaveric elbows (male:female, 56:20; mean age, 81 years) for patterns of cartilage erosion that could be due to ALRI. These included erosions on the lateral trochlear ridge (LTR) lesion, crescent rim of the radial head (RC) lesion or the ventral capitellum (VC) lesion. The extent and location of the lesions were mapped by image processing of photographs of the humeral and radial articular surfaces, and the degeneration of the articular surface was graded.
Results
Ten of 76 specimens (13%) had one or more lesions consistent with ALRI. LTR lesions were most common and were seen in 10 of 10 specimens (100%), typically involving the distal 30% of the LTR. RC lesions were seen in 9 of 10 and were located on anteromedial crescent of the radial head ranging from 6 to 10 o’clock. VC lesions were seen in 8 of 10 specimens directed anteroinferiorly about 60° to the long axis of the humerus.
Conclusions
ALRI is a possible mechanism initiating primary OA of the elbow. It has a characteristic pattern of triple lesions involving the LTR, the RC, and the VC. Level of evidence: IV.

Keyword

Elbow; Anterolateral rotatory instability; Cartilage erosion; Triple lesions; Osteoarthritis