.

Seon Jong Lee, MD, Jae-Yeon Hwang, MD, Bong Cheol Kwon, MD PhD Department of Orthopedic surgery, Hallym University sacred heart hospital, Anyang, Korea

Diagnostic Accuracy of the Ulnocarpal Grinding and StressTestfor Symptomatic Triangular fibrocartilage complex tear

Introduction

Material/methods

Provocative tests play a critical role in guiding further tests and subsequent treatment for patients with ulnar-sided wrist pain. The ulnocarpal grinding test (UCGT) and ulnocarpal stress test (UCST) are well-known provocative tests for triangular fibrocartilage complex (TFCC) tear. However, there is a paucity of studies investigating the diagnostic value of these tests.

This study aimed to determine the diagnostic value of the UCGT and UCST for symptomatic TFCC tear.

This was a retrospective diagnostic study on two provocative tests for TFCC tear, performed at tertiary referral hospital.

We searched electronic medical record database at our institution for patients who presented with wrist pain and underwent 3.0 T-MRI or multi-detector CT-arthrography, and/or arthroscopy from January 2014 to Dec 2016.

We excluded patients with 1) age < 18 years, 2) fractures of the wrist, 3) infection or inflammation of the wrist including RA, gout, or CPPD, 4) no records of provocative tests, 4) severe pain and limitation of motion of the wrist such that ulnocarpal or ulnar grinding tests could not be performed.

Arthroscopy

The results of this study indicate that both the UCGT and UCST have limited diagnostic value for symptomatic TFCC tear, although the former had a significantly better sensitivity than the latter. Thus, provocative tests need to be regarded as part of the diagnostic process, and their results should be interpreted in the context of other relevant clinical information from history taking, laboratory tests, and imaging studies before establishing the diagnosis of symptomatic TFCC tear. Future studies with a prospective design and improved reference standard can elucidate the role of various provocative tests for symptomatic TFCC tear.

Reference1. Sammer DM, Rizzo M. Ulnar impaction. Hand Clin. 2010;26:549-57.2. Schmauss D, Pohlmann S, Lohmeyer JA, Germann G, Bickert B, Megerle K. Clinical tests and magnetic resonance imaging have limited diagnostic value for triangular fibrocartilaginous complex lesions. Arch Orthop Trauma Surg. 2016;136:873-80.

Conclusions

Multi-detector CT-arthrography.

Results

Provocative tests

1. The UCGT2

The patient put his or her elbow on the table with elbow in 90 of flexion. The examiner grab the distal forearm of the patient with one hand to prevent forearm rotation, and with the other hand, placed the wrist in maximum ulnar-deviation, and then applied axial load while passively moving patient’s wrist from ulnar deviation-flexion to ulnar deviation-extension. 2. The UCST1

The patient put his or her elbow on the table with the elbow in 90 of flexion. The examiner stabilized the proximal forearm of the patient with one hand, and with the other hand placed the wrist in maximum ulnar deviation, and then applied axial load while passively rotating the forearm through supination to pronation.

MRI

MRI was performed with a 3-T MRI system (Achieva, Philips Healthcare) with a dedicated eight-channel wrist coil (Achieva Sense, Philips Healthcare).

We performed arthroscopy in the standard manner.

Reference standard of the TFCC tear.

We used symptomatic TFCC tear as the reference standard and regarded patients with only TFCC tear associated with ulnar-sided wrist pain as disease-positive and patients with symptomless TFCC tear as disease-negative.

Statistical methods

We calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), negative likelihood ratio (LR), positive LR, and overall diagnostic accuracy, with their 95% confidence intervals, for the provocative tests. We used McNemar’s test to compare diagnostic accuracy of the two provocative tests. The level of statistical significance was set at P<0.05.

Participants

Of the 339 consecutive patients who visited our institution with wrist pain and underwent MRI, or CT-arthrography, and/or arthroscopy, a total of 178 patients were included in this study (Fig 1). A total of 121 patients were found to have TFCC tear.Of these patients, 110 patients who presented withulnar-sided wrist pain were allocated to thesymptomatic TFCC tear group, whereas theremaining 68 patients were allocated to the controlgroup.

Diagnostic value of provocative tests

Non-enhanced CT exam for the wrist is performed before contrast injection. After the precontrast images are obtained, the dorsal aspect of the wrist is prepared using an aseptic technique. A 1:1 solution of iohexol(Bonorex) and normal saline are mixed. The level of scaphoid waist is punctured until the needle touches the bone and the solution is injected. An injection is administered if the flow of contrast shows distal carpal row. An average total volume of 3ml of contrast solution is injected. Posteroanterior (PA) radiographs with neutral, lateral, and both oblique views are obtained just after the injection. Patients are moved to the CT suite and positioned supine with the wrist lying overhead in supination. High-resolution acquisition is performed with a 128 dual MDCT scanner(Somatom Definition Flash, Siemens Medical Solutions) at CARE dose(80, 140 kVp), 250mAs, and 40 x 0.6mm of collimation.

Fig. 1 A schematic diagram for the flow of the patients

The UCGT test showed a significantly better sensitivity than the UCST (P<0.001).

Table 1. Diagnostic accuracy of the UCGT and the UCST