Arthroscopy of the Distal Radioulnar Joint: Its Role in the Evaluation and Management of Ulnar Sided Wrist Pain and the Development of a Classification System for Proximal Partial Thickness Triangular Cartilage Complex Pathology: Level 3 Evidence

Abstract

Royalty: Arthrex (Boland)Speakers Bureau: Acumed Lecture Fee (Boland) Proximal triangular fibrocartilage complex (TFC) pathology can be underdiagnosed on MRI and a normal radiocarpal view of the TFC does not exclude pathology. The Hypothesis is that pathology exists within the distal radioulnar joint that is not seen on Radiocarpal arthroscopy alone. The aim of the study is to report a retrospective review of findings of DRUJ Arthroscopy and develop a classification system of partial thickness TFC pathology. A retrospective review of all wrist arthroscopic surgery completed by a single surgeon was performed. All cases (94) over a one year period were reviewed and all arthroscopic surgery with a normal TFC on inspection through radiocarpal portals were included. All radiology was reviewed to determine the sensitivity and specificity of MRI in helping diagnose proximal TFC pathology. All radiographs were reviewed to determine if ulnar variance had any impact on the presence of proximal TFC tears. Intraoperative findings were then reviewed and the identified pathology classified into subgroups depending on the location and type of tear. 34 wrist arthroscopies were included all of whom had a normal TFC on radiocarpal arthroscopy. There was no correlation with ulnar variance and the presence of proximal TFC pathology. The sensitivity of MRI in detecting a proximal TFC tear was 70%. A Positive indentation sign was identified in 12 patients with proximal TFC pathology, while sensitivity of this finding is 35% it may be useful indicator that pathology may exist in proximal TFC. Tears were classified according to location on the TFC, they were described as delaminating, flap lacerations or fibrillated. Chondromalacia of the ulnar head and DRUJ stability and lunotriquetral pathology was also assessed and included in the classification. This study highlights the importance of performing distal radioulnar joint arthroscopy. MRI is a useful preoperative investigation but has poor sensitivity in the diagnosis of proximal TFC pathology. Ulnar variance is not predictive of proximal TFC pathology. Proximal TFC pathology frequently exists in the presence of an apparently normal TFC on radiocarpal arthroscopy. Subtle change in the lunotriquetral joint and TFC on radiocarpal arthroscopy that may indicate a proximal TFC pathology. The development of a classification system for describing these proximal TFC pathologies is useful for further clinical and scientific research. We recommend DRUJ arthroscopy as is useful adjunct to wrist arthroscopy and significant pathologies can be identified.