I agree, and you should also check Lorenzo's other works including his PhD Thesis. If there is one guy specialized in Pre-sapiens hands, it's him. Check out other articles by him, as well:
Article Hand and foot remains from the Gran Dolina Early Pleistocene...
Article Early Pleistocene human hand phalanx from the Sima del Elefa...
Article Three hands: one year later The hand of the Neandertals: dex...
Conference Paper One tarso-metatarsal association from the Middle Pleistocene...
This is interesting, and most valuable to understand modern Humans.
Thank you for your question. I have been trying to unsderstand the anatomy of the human hand, from the perspective of functional and evolutionary adaptations, for some years, now, as I chose this subject for my first academic works, as an anatomist.
You'll find some important comments and bibliographic references on a question I proposed, last year and arose several interesting contributes
The November issue of National Geographic included a long report on recent escavations for humanoid skeletons, in South Africa, showing a complete skeleton of humanoid hand with oponency capacity and a trapezio-meatacarpal joint very similar to modern humans.
You have the PHd of Isabelle Villemeur (Université Bordeaux 1) for the hand .(Etude morphologique et biomécanique du squelette de la main des Néandertaliens : comparaison avec la main des hommes actuels)
and the PHd of Anne Hambucken for the Member Sup. HAMBUCKEN, A. (1993). Variabilité morphologique et metrique de l'Humerus, du Radius et de l'Ulna des Néandertaliens. Comparaison avec l'Homme moderne. Thèse de Doctorat, Université Bordeaux I.
a left second metacarpal of Neanderhal man is described in this paper (p. 581-582, fig. 2A):
Ben Mersey, Rebecca S. Jabbour, Kyle Brudvik and Alban Defleur, Neanderthal hand and foot remains from Moula-Guercy, Ardèche, France. American Journal of Physical Anthropology 152 (4), December 2013, p. 516–529.