In the sensory examination performed 20 min later, sensory loss was noted in the LFCN, genitofemoral, anterior femoral cutaneous, obturator, and saphenous nerves. ...patient reported significant quadriceps weakness with the inability to achieve a straight leg raise. The advantages of PENG block to LPB are as follows: it can be applied in the supine position; injection point is far from neurovascular tissues; it is relatively safer for patients using anticoagulants; and bilateral block probability is nearly zero. ...although quadriceps weakness has been previously reported after PENG block 2, its probability is delivered at high volumes as in our case 1. ...although it is not yet possible, in the future, cadaveric, radiologic, and randomized controlled studies will provide answers to the following questions: can PENG block be an alternative to lumbar plexus block?