Simplified four-strand repair in which basic two-strand core suture is supplemented by horizontal mattress suture and running-lock stitch. A, Tajima core sutures in place. Back wall (dorsal) running-lock peripheral epitendinous stitch in progress. B, Back wall suturing completed. C, Mattress core suture added in palmar tendon gap. D, All core sutures tied. E, Completion of running-lock peripheral epitendinous suture. F, Repair completed. SEE TECHNIQUE 66.1.