Intramuscular Degloving Injury of the Rectus Femoris From Kickball: A Case Report and Review.

Intramuscular degloving injuries (IDIs) are a rare and unique type of muscle injury where there is a dissociation between the inner and outer components of a particular muscle. This type of injury is seen exclusively within the rectus femoris (RF) muscle due to its unique muscle-within-a-muscle anatomy and represents 9% of RF injuries. Despite the significance of this injury, limited knowledge exists regarding the mechanism, management, and prognosis of IDIs, and IDIs are not currently included among the various muscle injury classifications. We present a 38-year-old active male with a one-week history of acute onset right anterior mid-thigh pain and palpable lump after playing kickball. Right thigh MRI revealed an IDI of the RF muscle, edema within the inner and outer muscular portions of the muscle, and a retraction of the torn inner indirect myotendinous complex of the RF. He was managed with physical therapy while being advised to avoid aggressive quadriceps contractions, high-intensity, or high-impact exercise. This is the first reported case of an IDI that occurred in an older recreational athlete (versus young competitive athletes), and the first case of an IDI in a kicking sport other than soccer (kickball). This case emphasizes the importance of a broader awareness of this injury, and a heightened index of suspicion is advised in assessing potential IDIs to improve patient prognosis and rehabilitation. Given the limited understanding and rarity of this injury, we also provide a comprehensive review describing the IDI to the RF.