Elastic plastic fracture mechanics relies on the finite element method both as an engineering tool to evaluate residual strength of a damaged structure and to implement research theories that cannot be evaluated analytically. One common formulation assumes that the crack plane is flat and that the structure is symmetric about the crack plane. This situation arises for typical laboratory coupons such as the compact tension and middle crack tension specimens. Crack growth is modeled by monitoring analysis results for a critical fracture criterion, extending the crack, and resuming the analysis. When a symmetry plane corresponds to the crack-plane, an efficient crack growth procedure called nodal release can be used. A typical implementation reduces to the simultaneous solution of a set of linear equations, each of which corresponds to a displacement in the body being modeled. The system of equations is symmetric positive definite and sparse. This paper presents scalable sparse matrix factorization and update techniques required for efficient crack extension using nodal release.