The trapeziometacarpal screw home torque mechanism as a clinical indicator of the posterior joint ligament complex integrity: A cadaveric investigation.

BACKGROUND: To date, no clinical test provides specific objective information on the integrity of key ligamentous support of the trapeziometacarpal (TMC) joint. PURPOSE: To examine the potential of the TMC joint screw home torque mechanism (SHTM) in estimating the integrity of the posterior ligament complex in older adult population. STUDY DESIGN: Cross-sectional laboratory-based study. METHODS: Twenty cadaver hands presenting with various degrees of TMC joint degradation ranging from none to severe osteoarthritis (OA) were radiographed in multiple positions to establish their degeneration status, joint mobility, and amount of dorsal subluxation at rest and with the application of the SHTM. Comparisons and correlations between degeneration status, joint mobility, subluxation reduction and ligament status obtained from dissection were calculated. RESULTS: No significant statistical correlation was demonstrated with the subluxation reduction ratio of the SHTM and the combined ligament complex value however, a moderate negative correlation was found with dorsal central ligament injury at 21 Nm (τb = -0.46, p < 0.05) and 34 Nm (τb = -0.45, p < 0.05). A statistically significant reduction of radial subluxation of the TMC joint was observed between the subluxation at rest (M = 5.2, SD = 1.9) and subluxation with SHTM of 21 Nm (M = 4.4, SD = 2.4), t (19) = 3.2, p = 0.01, 95% CI [0.3, 1.4] and subluxation with SHTM of 34 Nm (M = 4.3, SD = 2.6), t (19) = 2.6, p = 0.02, 95% CI [0.2, 1.5]. CONCLUSION: Our results did not support the SHTM as indicator of the TMC posterior ligament complex integrity however, it demonstrated 100% stabilization effect with non-arthritic TMC population.

Clinical evaluation of thumb base osteoarthritis: A scoping review.

Introduction: Thumb base osteoarthritis (OA) is a prevalent hand OA phenotype, associated with specific risk factors, treatment strategies, and requiring a distinct subset of evaluative approaches. This paper aimed at surveying our clinical evaluative methods and identifying gaps in our ability to capture the thumb's unique attributes and how they could impact our treatment recommendations. Methods: A scoping review was conducted in accordance with the Joanna Briggs Institute methodology to gather relevant published and non-published articles regarding clinical tests currently available to assess the physical presentation of thumb base OA with special consideration of its specific multifactorial parameters namely architecture, ligaments, biomechanics, neuromuscular control, and proprioception. A full search strategy of MEDLINE, CINAHL, EMBASE, Scopus, Google Scholar, and Clinical Trials.gov from their inception through May 2020 was performed. Results: Of 1936 citation identified, 54 met the inclusion criteria. Fifty-two clinical physical tests for the evaluation of thumb base OA were extracted, most of which well suited to address research questions regarding efficacy of clinical intervention, however providing limited information regarding the underlying impairments of ligaments, biomechanics, neuromuscular or proprioceptive components. Conclusions: The tests and measures specific to the basal thumb OA phenotype, and capable of isolating its multifactorial contributors are scarce. Our limited physical assessment repertoire impedes our ability to describe and answer explicative research questions. Without these we cannot evaluate the effect of conservative management and provide specific treatment recommendations. Further research is needed to develop and validate distinct clinical tools for this debilitating pathology.