Bone abnormalities are common in theropod dinosaur skeletons, but before now no specimen was known with more than four afflicted bones of the pectoral girdle and/or forelimb. Here we describe the pathology of a specimen of the theropod dinosaur Dilophosaurus wetherilli with eight afflicted bones of the pectoral girdle and forelimb. On its left side the animal has a fractured scapula and radius and large fibriscesses in the ulna and the proximal thumb phalanx. On its right side the animal has abnormal torsion of the humeral shaft, bony tumors on the radius, a truncated distal articular surface of metacarpal III, and angular deformities of the first phalanx of the third finger. Healing and remodeling indicates that the animal survived for months and possibly years after its ailments began, but its right third finger was permanently deformed and lacked the capability of flexion. The deformities of the humerus and the right third finger may be due to developmental osteodysplasia, a condition known in extant birds but unreported in non-avian dinosaurs before now.
Ok, from what I read in other responses was that the forelimbs were't necessarily used in predation, and that these injuries did not result in death.
The paper says this is UCMP 37302https://urldefense.proofpoint.com/v2/url?u=https-3A__&d=CwICaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=x82f3Wlkwtmbr1z8IAt9jA&m=GTD-VN_dAt7jhjCgRw34dVUob903e5Lozecmv4jHwdo&s=Gw383rIZKKGIe0yN6_SLymwaUhIr948IF05UoURSlx4&e=
upload.wikimedia.org/wikipedia/commons/1/12/DilophosaurusROM1.JPGand that they did a surface examination of this fairly complete specimen. No other injuries were reported, but I wonder if it is possible that there were if the whole skeleton was not accessible.
A fight of some kind is certainly possible if not probable, but another cause suggested itself to me, and that is that it took a bad fall while running. A face plant, as it were, and the forelimbs injured while hitting the ground. If so then the jaw should exhibit injury too.
What I read is that the skull was incomplete when found, and the 1954 paper is not accessible to me so I couldn't tell if the skull might indeed have suffered some injury.