the tooth sockets for 10 tooth rows within . The quadrate bone at the base of the skull has an exceptionally low stature at , in contrast to in Mantellisaurus and in Iguanodon. Based on the ratio between the length of the snout and the length of the rest of the skull in iguanodonts, the total length of the holotype's skull may have been in life. Lurdusaurus may have had 12 to 14 neck vertebrae. Therefore, the maximum length of the neck is . The neck vertebrae are about the same size as the dorsal vertebrae (the torso, before the sacrum and pelvis), whereas those of European iguanodonts 85–90% the size of the dorsals. Because Iguanodon has 28 presacral vertebrae, Lurdusaurus potentially had at least 14 dorsals. This would make the neck proportionally quite long, as long as the dorsal series. Compared to European iguanodonts, the dorsal centra are proportionally larger and have shorter neural spines (which project straight up from the centrum) and less steep transverse processes (which project up obliquely). Like all derived iguanodonts, the sternum is hatchet-shaped, with a rod-shaped projection caudolaterally (tailwards towards the side). The sacrum, based on the scars on the ilium begotten from sacral ribs, may have measured . Lurdusaurus could have had 15 proximal caudal vertebra (tail vertebrae which bear transverse processes), which would have represented a third of the entire tail series. This would equate to a tail, and a total body length of . It may have been tall at the hips. Based on the length of the ribs, the stomach may have been less than off the ground when standing quadrupedally (on all-fours). Based on the circumferences of the limbs – for the humerus and for the femur – Taquet and Russell estimated that the holotype weighed approximately , conspicuously heavy for an ornithopod this size. In 2016, however, Gregory S. Paul proposed a significantly lower size estimate of in length and in body mass. The headward dorsal ribs are preserved in their original positions, and show the torso was rather rotund. The diverging wings of the ilia and horizontally-orientated tailward dorsal ribs indicate a flat back about across. The limbs are exceptionally massive and proportionally stout. The forelimbs are 60% the size of the hindlimbs. The metacarpals in the wrist were fused together into a massive block, which is also exhibited in Iguanodon, Ouranosaurus, and Camptosaurus. Like Camptosaurus