Comparative Analysis of Prosthetic (Touch) and Arthroplastic Surgeries for Trapeziometacarpal Arthrosis: Functional Outcomes and Patient Satisfaction With a 2-Year Follow-Up.

Purpose: Trapeziometacarpal (TMC) joint prosthesis poses its own challenges for the treatment of TMC arthrosis, especially when compared with the present gold standard, arthroplasty. The aim of this study was to highlight possible outcome differences and patients' satisfaction regarding the treatment of TMC arthrosis. Methods: We evaluated 100 patients with TMC arthrosis treated in two centers and divided into two groups: group A received TMC prosthesis (Touch), whereas group B was treated with arthroplasty, with a 2-year follow-up period. Results: In a comparative analysis, findings revealed group A's superiority in the shortened disabilities of the arm, shoulder and hand questionnaire scores at 1 and 6 months, with significant differences: 34.6% vs 67.1% and 2% vs 9.1%, respectively (P < .0001). Although group A also showed lower the shortened disabilities of the arm, shoulder and hand questionnaire scores at 3 months, this was not statistically significant. Notably, at 1 and 2 years, group A demonstrated better scores without statistical significance. The Kapandji score differed significantly at 6 months: 9.8 vs 9.1 (P = .029). Although the visual analog scale showed generally lower values for the prosthesis group, no statistical differences emerged. Additionally, the M1/M2 ratio became significant postoperatively, favoring group A (P < .05). Conclusions: Trapeziometacarpal prosthesis shows promise for TMC arthrosis, enhancing function, thumb length, and patient recovery, warranting further research and x-ray guidance. Type of study/level of evidence: Therapeutic III.

Resection arthroplasty versus dual mobility prosthesis in the treatment of trapeziometacarpal joint osteoarthritis: A 3 year non-randomized prospective study.

Purpose: Resection arthroplasty (RA) is still the most common surgical intervention for the treatment of symptomatic trapeziometacarpal (TMC) joint osteoarthritis. The implantation of a dual mobility prosthesis may represent a joint function preserving alternative. The aim of the presented study is to prospectively compare the outcomes of RA with dual mobility prosthesis. Methods: In this 2-center non-randomized prospective study, we compared results of RA (n = 22) with implantation of a dual mobility prosthesis (n = 49) (Touch®) at a minimum of 3-year follow-up. The patients underwent preoperative assessments and postoperative follow-up at 6 weeks, 3, 6, 12, 24, and 36 months. Comparisons were conducted, covering pain assessment via the visual analogue scale (VAS), thumb range of motion (ROM), pinch and grip strength, as well as functional scores and radiological examinations. Results: The time intervals from surgery until absence of pain on the VAS (3 months: 3 vs 1, p = 0.0001), recovery of ROM in radial (3 months: 33° vs 42°, p = 0.0001), and palmar abduction (3 months: 33° vs 48°, p = 0.0001), were significantly longer for the RA group compared with the prosthesis group. At 3-year follow-up there was no significant difference in absence of pain, ROM and grip strength between both groups. Key pinch strength was significantly weaker in the RA group compared to prosthesis group at 3 months (2.6 kg vs 4.6 kg, p = 0.001), to 3-year follow-up (3.1 kg vs 5.7 kg, p = 0.0001). The final mean DASH (15.5 vs 13.2, p = 0.01) and MHQ scores (78 vs 82, p = 0.01) were significantly better in the prosthesis group. Conclusion: Both techniques show high patient satisfaction in mid-term follow-up. Dual mobility TMC joint arthroplasty seems to be associated with a superior pinch strength and shorter time of recovery as compared to patients after RA.

Proposed Radiographic Parameters to Optimize Clinical Outcomes in Trapezio-Metacarpal Prosthesis Placement Using CT Imaging, with 1-Year Follow-Up.

PURPOSE: Addressing trapezio-metacarpal (TMC) osteoarthritis often involves considering TMC joint replacement. Utilizing TMC prostheses offers advantages such as preserving the thumb length and more accurately replicating the thumb's range of motion (ROM). TMC prostheses have an intrinsic risk of dislocation and aseptic loosening. Analyzing pre- and postoperative imaging can mitigate complications and improve prosthetic placement, providing insights into both successes and potential challenges, refining overall clinical outcomes. MATERIALS AND METHODS: We conducted a prospective analysis of 30 patients with severe TMC arthritis treated with a Touch© (Kerimedical, Geneva, Switzerland) prosthesis in 2021-2023: X-ray and CT protocols were developed to analyze A) the correct prosthesis placement and B) its correlation with clinical outcomes (VAS, Kapandji and QuickDASH scores) by performing Spearman correlation analysis. RESULTS: The average differences in trapezium height and M1-M2 ratio pre- and post-surgery were, respectively, 1.8 mm (SD ± 1.7; p < 0.001) and 0.04 mm (SD ± 0.04; p = 0.017). Pre-to-postoperative M1 axis length increased by an average of 2.98 mm (SD ± 3.84; p = 0.017). Trapezial cup sinking, indicated by the trapezium index, measured 4.6 mm (SD ± 1.2). The metacarpal index averaged at 11.3 mm (SD ± 3.3). The distance between the centers of the trapezium distal surface and the prosthesis cup was 2.23 mm (SD ± 1.4). The Spearman correlation analysis gave the following results: negative correlations were highlighted between postoperative VAS scores and the M1/M2 ratio and residual trapezium height (correlation coefficient: -0.7, p = 0.03 and -0.064, p = 0.03, respectively) at 6 months; a negative correlation was found at the 3-month mark between QuickDASH and the trapezium residual height (correlation coefficient: -0.07, p = 0.01); and a positive correlation was found for the trapezium index at 1 month (correlation coefficient: 0.07, p = 0.03) and 3 months (p = 0.04) using the Kapandji score. Similarly, we found a positive correlation between the distance between the prosthesis and trapezium centers and QuickDASH score at 1 and 3 months (correlation coefficient: 0.066, p = 0.03; correlation coefficient: 0.07, p = 0.05, respectively) and a positive correlation between prosthesis axis and the residual first metacarpal angle with QuickDASH score at 3 months (correlation coefficient: 0.07, p = 0.02). CONCLUSIONS: Pre- and postoperative systematic imaging analysis should become a method for predicting complications and guiding recovery in TMC prosthesis: CT imaging could provide us with radiographical landmarks that are intrinsically linked to clinical outcomes. Further research is necessary to fuel a protocol for the correct intraoperative TMC prosthesis implantation.

The Effect of the Joint Capsule and Anterior Oblique Ligament on Dorsal Subluxation of the First Metacarpal During Key Pinch.

Laxity of the anterior oblique ligament (AOL) and/or the dorsoradial ligament (DRL) are believed to contribute to the progression of osteoarthritis in the trapeziometacarpal joint through increased dorsal subluxation. Stress radiographs during functional tasks, such as key pinch, can be used to evaluate such joint instability. Cadaveric experiments can explore joint contact pressures as well as subluxation under varying conditions, to gain knowledge about joint mechanics. The disturbance of supporting tissues, such as the joint capsule, during experiments may affect the recorded stability of the joint. To evaluate potential effects of opening the joint capsule and severing the AOL, eleven cadaveric specimens were rigged to simulate key pinch. An anteroposterior (AP) radiograph of the hand was recorded for each specimen while intact, after partially opening the joint capsule and after sectioning the AOL. First metacarpal subluxation levels were compared between the intact joint, partially open joint capsule, and sectioned AOL. Neither opening the joint capsule nor cutting the AOL had a statistically significant effect on metacarpal subluxation. The results indicate that partially opening the joint capsule has a negligible effect on joint mechanics and support recent studies that postulate that the AOL plays a less substantial role in preventing subluxation.

An anatomical study on the effectiveness of Arthrex Mini TightRope® ligament reconstruction in an unstable trapeziometacarpal joint.

INTRODUCTION: Laxity in the trapeziometacarpal (TMC) joint is a debilitating condition usually affecting a young population. It can be treated operatively with ligament reconstruction. The purpose of this study was to determine the effectiveness of the Arthrex Mini TightRope® in reinforcing the stabilizing ligaments in an unstable TMC joint without decreasing the range of motion of the thumb. This method was compared with the "gold standard" published by Eaton and Littler in 1973. MATERIALS AND METHODS: Six fresh frozen arms from five cadavers were included. TMC joint laxity was measured on stress view radiographs as the ratio of the radial subluxation (RS) of the first metacarpal in relation to the trapezium, by the first metacarpal articular width (AW) (as described by Wolf in 2009). Measurements of the pre- and post-operative range of motion (ROM) were performed and compared. RESULTS: Both the Arthrex Mini TightRope® and the Eaton-Littler stabilization improved the stability of the TMC joint. The pre-operative laxity value (ratio RS/AW) of 0.27 was significantly (P = 0.02) improved by each of the surgical interventions (Eaton-Littler RS/AW = 0.05 and Tightrope RS/AW = 0.09). The pre- and post-operative range of motion was not significantly different by each of the surgical interventions. There were no significant differences between the two stabilizing methods regarding laxity or range of motion. CONCLUSION: The Arthrex Mini TightRope® provided a good stabilization method for the TMC joint in this anatomical model without compromising the range of motion.

Impact of Osteoarthritis and Total Joint Arthroplasty on the Kinematics of the Trapeziometacarpal Joint: A Pilot Study.

PURPOSE: To quantify the effect of osteoarthritis (OA) and total trapeziometacarpal (TMC) joint replacement on thumb kinematics during the primary physiological motions of the thumb. METHODS: We included 4 female patients with stage III TMC OA. A computed tomography-based markerless method was used to quantify the 3-dimensional thumb kinematics in patients before and after TMC joint replacement surgery with the Arpe implant. RESULTS: Trapeziometacarpal OA led to a marked decrease of internal rotation and abduction of the first metacarpal (MC1) during thumb flexion and a decrease of MC1 adduction during thumb adduction. As a compensatory phenomenon, the trapezium displayed increased abduction. The absence of MC1 translation in the ball-and-socket implant seems to induce a decrease of MC1 adduction as well as a decrease of trapezium adduction during thumb adduction, compared with OA and healthy joints. Implant replacement displayed an unchanged MC1 flexion during thumb flexion and seemed to slightly increase MC1 axial rotation during thumb flexion and adduction. Abduction and adduction of the MC1 are limited and compensated by this somewhat increased axial rotation, allowing more efficient thumb opposition. CONCLUSIONS: The study highlights that advanced TMC OA mainly restricts the MC1 mobility. We also showed that, whereas total joint arthroplasty is able to restore thumb function, it cannot fully replicate the kinematics of the healthy TMC joint. CLINICAL RELEVANCE: The quantification of TMC joint kinematics in OA and implanted patients is essential to improve our understanding of TMC OA as well as to enhance the functionality of implant designs.

In vivo biomechanical behavior of the trapeziometacarpal joint in healthy and osteoarthritic subjects.

BACKGROUND: The contact biomechanics of the trapeziometacarpal joint have been investigated in several studies. However, these led to conflicting results and were mostly performed in vitro. The purpose of this study was to provide further insight on the contact biomechanics of the trapeziometacarpal joint by in vivo assessment of healthy and osteoarthritic subjects. METHODS: The hands of 16 healthy women and 6 women with trapeziometacarpal osteoarthritis were scanned in positions of maximal thumb extension, flexion, abduction and adduction during three isometric tasks (lateral key pinch, power grasp and jar twist) and in thumb rest posture (relaxed neutral). Three-dimensional surface models of the trapezium and first metacarpal were created for each thumb configuration. The articular surface of each bone was measured in the neutral posture. A computed tomography-based proximity mapping algorithm was developed to calculate the distance between opposing joint surfaces, which was used as a surrogate for intra-articular stress. FINDINGS: Distinct proximity patterns were observed across tasks with a recurrent pattern reported on the volar aspect of the first metacarpal. The comparison between healthy and arthritic subjects showed a significantly larger articular area, in parallel with a significant joint space narrowing and an increase in proximity area in arthritic subjects. We also observed severe articular deformations in subjects with late stage osteoarthritis. INTERPRETATION: This study has increased our insight in the contact biomechanics of the trapeziometacarpal joint during tasks and positions of daily life in healthy and arthritic subjects, which might contribute to a better understanding of the occurrence mechanisms of degenerative diseases such as osteoarthritis.

In vivo kinematics of the thumb during flexion and adduction motion: Evidence for a screw-home mechanism.

The thumb plays a crucial role in basic hand function. However, the kinematics of its entire articular chain have not yet been quantified. Such investigation is essential to improve our understanding of thumb function and to develop better strategies to treat thumb joint pathologies. The primary objective of this study is to quantify the in vivo kinematics of the trapeziometacarpal (TMC) and scaphotrapezial (ST) joints during flexion and adduction of the thumb. In addition, we want to evaluate the potential coupling between the TMC and ST joints during these tasks. The hand of 16 asymptomatic women without signs of thumb osteoarthritis were CT scanned in positions of maximal thumb extension, flexion, abduction, and adduction. The CT images were segmented and three-dimensional surface models of the radius, scaphoid, trapezium, and the first metacarpal were created for each thumb motion. The corresponding rotations angles, translations, and helical axes were calculated for each sequence. The analysis shows that flexion and adduction of the thumb result in a three-dimensional rotation and translation of the entire articular chain, including the trapezium and scaphoid. A wider range of motion is observed for the first metacarpal, which displays a clear axial rotation. The coupling of axial rotation of the first metacarpal with flexion and abduction during thumb flexion supports the existence of a screw-home mechanism in the TMC joint. In addition, our results point to a potential motion coupling between the TMC and ST joints and underline the complexity of thumb kinematics. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1556-1564, 2017.

In vivo contact biomechanics in the trapeziometacarpal joint using finite deformation biphasic theory and mathematical modelling.

The assessment of the contact biomechanics in the trapeziometacarpal (TMC) joint during functional tasks represents a relevant way to obtain a better understanding of the onset of osteoarthritis (OA). CT scans of the hand region of 20 female volunteers were taken in relaxed neutral, lateral key pinch and power grasp configuration. 3D models of the first metacarpal (MC1) and the trapezium were created. The articular area of each bone was quantified and a mathematical model was developed in Matlab to evaluate the projected contact area and stress distribution of each bone. The articular areas of the MC1 and the trapezium presented no significant difference. A slightly smaller projected contact area was calculated for the trapezium compared to the MC1. Similar amounts of stress were reported in the neutral and lateral pinch configurations. The highest stress levels were observed during power grasp. Very consistent results for high stress location on the volar/radial articular sub-region were found in the neutral and power grasp configurations. More variation was reported during lateral pinch. The mathematical model presented in this paper offers the possibility to predict contact patterns within the TMC joint based on in vivo CT images.