Scaphotrapeziotrapezoid osteoarthritis: From the joint to the patient

Abstract

Scaphotrapeziotrapezoid osteoarthritis (STT OA) is common and often associated with thumb basal joint arthritis. Pain at the base of the thumb on the volar aspect and during resisted extension is characteristic of symptomatic STT OA. If conservative treatment fails, surgical treatment may be offered. In case of STT OA, treatment may range from arthrodesis to trapeziectomy (isolated or associated with ligament reconstruction and/or interposition). Any preoperative intracarpal instability (DISI) can be exacerbated by resecting more than 3 or 4 mm of the distal pole of scaphoid. For peritrapezial osteoarthritis, trapeziectomy is the logical solution, but it exposes the patient to known complications: loss of strength, long recovery, trapeziometacarpal impingement. Initial treatment of thumb basal joint arthritis by arthroplasty is also an option. Treatment of both sites is also possible by interposition of pyrocarbon implants. In all cases (isolated or associated STT OA) and no matter the technique chosen, maintaining the scaphoid height (arthrodesis, resection < 3 mm and/or associated interposition) and performing oblique trapezoidal osteotomy (to prevent scaphoid–metacarpal impingement) are the two crucial elements of surgical treatment.

Résumé

L’arthrose scapho-trapézo-trapézoïdienne (STT) est fréquente et souvent associée à une rhizarthrose. Les douleurs de la base du pouce, palmaires, et en extension contre résistance sont caractéristiques d’une arthrose STT symptomatique. Si le traitement médical échoue, un traitement chirurgical peut être proposé. En cas d’arthrose STT, les traitements possibles sont l’arthrodèse, la trapézectomie isolée, associée à une ligamentoplastie et/ou à une interposition. La présence d’une instabilité intracarpienne préopératoire (DISI) risque d’être aggravée par une résection du pôle distal du scaphoïde supérieure à 3 ou 4 mm. En cas d’arthrose péritrapézienne, la trapézectomie est la solution logique mais elle expose aux complications connues : perte de force, longueur de l’obtention du résultat, risque de conflit métacarpo-trapézoïdien. Le traitement premier de la rhizarthrose par arthroplastie est aussi une option. Un traitement des deux sites est aussi possible par des implants en pyrocarbone étagés. Dans tous les cas (arthrose STT isolée ou associée) et quelle que soit la technique choisie, conserver la hauteur du scaphoïde (arthrodèse, résection < 3 mm et /ou interposition associée) et réaliser une ostéotomie trapézoïdienne oblique (pour empêcher le conflit scapho-métacarpien) sont les deux éléments essentiels du traitement chirurgical.

Introduction

The first description of scaphotrapeziotrapezoid (STT) osteoarthritis (OA) is attributed to Carstam et al. [1]. The STT joint is the third most common location for osteoarthritis in the wrist after the thumb basal joint and carpal collapse. The condition occurs more frequently in women (4:1 female to male ratio) above 50 years of age [2].

The frequency of STT OA varies depending on whether the incidence was determined in cadavers (83% with predominantly trapezoid arthritis in specimens over 80 years of age) or on radiographs (5%–11%) [3], [4]. North and Eaton found isolated STT OA in 6% of cases after 50 years, but in 46% of cases where the trapeziometacarpal (TMC) joint was involved [5]. Katzel et al. found 64% STT OA in a study of 89 patients [6]. In a radiographic study, Scordino et al. found a prevalence of 16% in a group of patients in their 50 s who were consulting a hand surgeon. In that study, being older, having scapholunate diastasis greater than 3 mm and TMC OA were predictive of the occurrence of STT OA. This prevalence increased to 59% as the patient’s age increased [7]. Moreover, the radiographic or CT appearance were less relevant than direct vision and intraoperative observations [8]. Based on the literature (patient age, intraoperative observations, radiographic analysis), the rate of STT OA ranges between 10% and 59%, but can reach 64% for intraoperative evaluations during trapeziectomy [8].

The presence of visible calcium deposits on radiographs at the STT joint, scaphoid verticalization, and its impaction on the radius are considered pathognomonic for chondrocalcinosis, as described by Saffar [9].