Muscular dystrophies comprise a heterogeneous group of neuromuscular diseases characterized by progressive degeneration and weakness of skeletal muscles. We investigated the hypothesis that an altered proprioceptive feedback contributes to the instable gait and frequent falls in patients with muscular dystrophy. Proprioceptive information is generated by muscle spindles, complex sensory organs found in almost every muscle that detect changes in muscle length and the speed of muscle stretching. We analyzed muscle spindle function and morphology in wildtype-, as well as in dystrophin-, utrophin- and dysferlin-deficient mice. To obtain muscle tissue for immunohistochemistry, mice were deeply anaesthetized using ketamine and xylazine. After transcardial perfusion with 4% paraformaldehyde, the muscle was dissected, sectioned in a cryostat, stained with the appropriate antibodies and analyzed using confocal microscopy. Immunofluorescence staining demonstrated the presence of all three proteins in the central region of muscle spindles from wildtype- and their absence in spindles from the respective mutant mice. Dystrophin was concentrated in the sarcolemma of intrafusal fibers but excluded from the contact region with the sensory neuron. In dystrophin-deficient mice, dystrophin was undetectable but utrophin expression was severely upregulated, potentially compensating the absence of dystrophin. The total number and the overall morphology of muscle spindles in soleus muscles of dystrophin-deficient, Dysf-/- and utrophin-deficient mice appeared unchanged, demonstrating that intrafusal muscle fibers are less sensitive to degeneration compared to extrafusal muscle fibers. Proprioceptive sensory neuron responses to stretch were assayed using an isolated muscle-nerve preparation from the EDL muscle. To this end, mice were sacrificed by cervical dislocation and the EDL muscle together with the deep peroneal branch of the sciatic nerve were dissected and placed in a tissue bath containing oxygenated artificial cerebrospinal fluid. Extracellular recordings during ramp-and-hold stretches as well as during sinusoidal vibrations revealed that dystrophin-deficient and Dysf-/- mice have an increased resting discharge and a lower action potential firing rate during sinusoidal vibrations particularly at low frequencies. Utrophin-deficient mice reacted to ramp-and-hold stretches and sinusoidal vibrations similar to wildtype mice. These results demonstrate that dystrophin and dysferlin are required for normal muscle spindle function and suggest that an impaired proprioceptive feedback might contribute to the instable gait and the frequent falls in patients with muscular dystrophy. The increase in the resting discharge results in an elevated general muscle tone, which might add to the degeneration of extrafusal fibers in muscular dystrophy patients.