13C MR spectroscopy can offer important metabolic information in the musculoskeletal system without the use of ionizing radiation. In this work, we design and simulate a novel double-nuclear pTx RF coil array (8-channel per frequency) with ICE decoupling coils for proton MRI and 13C MRS of human extremities. Coupling was compared between the RF coil array with and without ICE elements demonstrating the significant decoupling effect of the ICE coils. Calculated B1+ field maps for both the proton MTLs and the 13C loops with ICE elements show sufficient transverse magnetization for MRI and MRS applications. Through the use of switch-tuned ICE decoupling elements, we have demonstrated the feasibility of dual-frequency pTx arrays for 1H imaging and 13C spectroscopy of human extremities at 7T.