An inverting circumferential suture for flexor tenorraphy

Zone two flexor tendon repair remains challenging with significant outcome variation using recognised techniques. Tendon adhesion formation results in poor outcomes and rehabilitation regimes aim to limit this. Some repairs augment strength, but increasing bulk mitigates against movement. This novel epitendinous technique causes tendon inversion with potential gliding benefits and improved outcomes. 60 porcine tendons were randomised to a 2-stranded modified Kessler or a 4-stranded Adelaide repair, then sudivided into three different circumferential technique groups: locked running, Silfverskiold, or a new inverting repair. Tendon load to failure (LTF), 2 mm gap formation, bulking effect and method of failure were analysed during digital tensiometry. Four-stranded repairs demonstrated better LTF than 2-stranded techniques. The inverting epitendinous and Silfverskiold repairs showed higher LTF characteristics than the locked running suture, and better tissue holding capacity. The inverting repair has similar properties to commonly used suturing methods and the conformation creates a smooth inverted repair.