[en] The use of boundary-matching techniques, as contained in R-matrix theory, to describe multichannel nuclear reactions is discussed. After giving a brief summary of the application of such techniques to the nuclear reactions in the ⁵He system, we discuss a simple extension of the description to include muons, which was used to calculate nuclear effects on the L = O eigenvalues of the dtμ molecule in various adiabatic approximations. Next, the form of the outgoing nαμ wavefunction is discussed, resulting in a new formulation of the amplitudes used to calculate the α-μ sticking fraction. Possible methods of solving for these amplitudes using the boundary-value approach are suggested, and some deficiencies of the ''standard'' expression for the sticking amplitudes are pointed out. 3 figs., 3 tabs