Assessment of Cartilaginous and Tendinous Lesions Following Intramedullary Compression Screw Fixation of Middle Phalangeal Fractures: A Cadaveric Study.

Abstract

Phalangeal fractures are undergoing surgical intervention more frequently and can be stabilized via a range of modalities. Intramedullary screw (IMS) fixation has become popular in the management of metacarpal and phalangeal fractures, with promising short- to medium-term results. Violation of articular cartilage and the terminal extensor tendon is a concern when IMS fixation is used in the middle phalanx. The aim of this study was to assess the cartilaginous and soft tissue footprint resulting from retrograde IMS insertion in the middle phalanx. Ten cadaveric hands underwent radiographic guided insertion of 1.7 and 2.2 mm diameter headless compression screws. The width of the extensor tendon lesion and the surface area of the surface defect within the articular cartilage were both measured using digital processing software. Using the 1.7 mm screw, the mean lesion involved 12.1% of the width of the extensor tendon and 1.8% of the total articular surface. Using the 2.2 mm screw, the mean lesion involved 20.4% of the width of the extensor tendon and 3.5% of the total articular surface. The use of retrograde intramedullary screw fixation in the middle phalanx results in minimal violation of the articular cartilage and terminal extensor tendon. This study finds minimal disruption of the articular cartilage and terminal extensor tendon when intramedullary screws are inserted into middle phalanges in a retrograde fashion. When combined with promising early- to mid-term clinical outcomes, these findings render intramedullary screw fixation a suitable therapeutic option in this cohort.