Total trapeziectomy and suspension ligamentoplasty: is there any interest to interpose a pyrocarbon Pi2® implant?

Total trapeziectomy with suspensioplasty remains one of the most widely used techniques in thumb osteoarthritis. Nevertheless, such a technique does not completely prevent collapse of the trapezial space. We wanted to know whether adding a pyrocarbon spacer allowed better keeping trapezial space and increasing strength. We compared two groups of patients matched on sex, age, manual labor and dominant side. In each group, they were 23 patients suffering from CMC1 osteoarthrosis, mean age was 62 years. Surgical technique consisted in a total trapeziectomy and suspensioplasty with a Gore-Tex(®) slip without spacer (group A) or associated with spacer Pi2(®) (group B). The follow-up was 25 months for group A and 15 months for group B. Height of the scaphometacarpal space represented 81.5% of trapezium height in group B versus 61.6% in group A. Better correction of hyperextension of the metacarpophalengeal joint was noted in group B. Between group A and group B, no difference was found according to pain (VAS 1.6 versus 1/10), mobility (opposition 9.44 versus 9.31; commissural opening 35.2° versus 37.2°) or strength (Jamar 19.1kg/F versus 16.8kg/F, pinch 4.35kg/F versus 4.67kg/F). DASH score was 16.9 and 25.1/100 respectively. We deplore three symapthetic reflex dystrophies in group A and seven radiological subluxations of the implant in group B. The total trapeziectomy with suspensioplasty gave satisfactory results for both series. The implant Pi2(®) seems to contribute keeping trapezial height, without functional advantages and with a risk of dislocation.