Here’s an excerpt from an article that might help:
Piper, Timothy J., Michael A. Waller, 2001: Variations of the Deadlift. Strength and Conditioning Journal: Vol. 23, No. 3, pp. 66?73.
The snatch grip DL (SGDL) places emphasis on the thoracolumbar fascia, erector spinae, and the shoulder girdle muscles that stabilize the scapulae. The positioning of the torso causes a great deal of hip flexion, which increases the load on the lumbar region and hip extensors. This is similar to the RDL, but the wide grip makes this exercise advantageous to clientele requiring increased upper back strength and scapular and spinal stabilization. Setup: The conventional stance is used, but the lifter uses a wide snatch grip. The distance between the hands in the snatch grip is determined from measuring the distance from the lateral side of one shoulder to the fist of the opposite arm abducted to shoulder level. Execution: The client pulls the bar off the floor using the hips to lift the bar instead of the back. Throughout the lift the back is held tight and fixed. The bar is kept close to the legs to reduce the amount of torque on the lumbar region. Scapular retraction continues throughout the exercise but is not exaggerated when movement is completed.
A variation of the snatch grip DL is the Smitty DL, which is performed on a 4?6-in. platform, and movement ceases when the bar is inferior to the patella. The technique is otherwise the same, emphasizing hip flexibility and back strength in the limited range of motion. Weightlifters will benefit as well as wrestlers, swimmers, and others requiring the increased strength in the shoulder girdle stabilizers.