Relationship Between Axial Radioulnar Incongruence With Cartilage Damage in Dogs With Medial Coronoid Disease

Abstract

Axial RUI is greater and more prevalent in elbows with severe cartilage disease, and consists most commonly of a short radius.

In vivo fluoroscopic kinematography of dynamic radio-ulnar incongruence in dogs

“…Our results are also in accordance with the amount of radio-ulnar translation reported in a cadaveric model of simulated triceps pull (Might et al, 2011). Therefore, the widely suspected dynamic radio-ulnar step creation during weight bearing activity (Gemmill et al, 2005;Kramer et al, 2006;Gemmill and Clements, 2007;Smith et al, 2009;Might et al, 2011;Gutbrod and Guerrero, 2012;Starke et al, 2013Starke et al, , 2014Krotscheck et al, 2014a;Mariee et al, 2014;Eljack and Bottcher, 2015) is a consistent physiological pattern of elbow kinematic in dogs. While the results of the current data prove the presence of dynamic RUI in canine elbow joints, the amplitude of dynamic translation was not different between normal and dysplastic joints.…”

“…Radio-ulnar incongruence (RUI) has been reported to occur concomitant to medial coronoid disease in up to 60% of clinical cases and has been shown to be related to the severity of medial compartment pathology (Eljack and Bottcher, 2015). Traditionally RUI has been defined as two forms of incongruence: (1) an abnormal shape of the trochlear notch of the ulna, leading to humero-ulnar incongruence (Wind, 1986;Wind and Packard, 1986) or (2) a step formation between the articular surfaces of the radius and ulna (short ulna or short radius), leading to radio-ulnar incongruence and secondary to this humero-ulnar conflict.…”

“…A static positive radio-ulnar incongruence (short radius) induces load shift from the radial head to the medial coronoid process (Krotscheck et al, 2014b;McConkey et al, 2016), with the consequence of mechanical overload of the medial joint compartment and degenerative changes such as fragmentation of the medial coronoid process (Samoy et al, 2006;Gemmill and Clements, 2007). According to Eljack and Bottcher (2015) we refer to RUI as "axial radio-ulnar incongruence", in contrast to local positive radio-ulnar incongruence at the tip of the medial coronoid process. Axial static RUI is thought to develop because of asynchronous growth between the radius and ulna (Samoy et al, 2006;Lau et al, 2015;Nemanic et al, 2016).…”

“…Axial static RUI is thought to develop because of asynchronous growth between the radius and ulna (Samoy et al, 2006;Lau et al, 2015;Nemanic et al, 2016). However, in a significant number of dogs with medial coronoid disease RUI is not present (Gemmill et al, 2005;Kramer et al, 2006;Eljack and Bottcher, 2015). This might be due to transient RUI during growth, with incongruence having resolved by the time of clinical presentation, which is usually months later.…”

CT evaluation of elbow congruity in dogs: radial incisure versus apical medial coronoid process fragmentation

“…In the 1980's, elbow incongruity was identified as a likely cause of MCPD (Wind , Wind & Packard ) but subsequent CT studies have revealed that there may or may not be incongruity of the elbow joint at the time of diagnosis (Gemmill et al . , Eljack & Böttcher ) and its exact contribution to the development of medial coronoid articular lesions remains incompletely understood. Axial incongruity can be defined as positive or negative; the ulnar articular surface either being proximal or distal to the radial articular surface, respectively (Lozier ) and may be observed at both the apex (Gemmill et al .…”