Volumetric muscle defects, such as those associated with cleft lip, often require multiple surgeries to repair, and the outcomes may be limited in terms of function and cosmesis. While tissue engineering strategies are being explored to facilitate repair of volumetric muscle defects in pre-clinical models, the models typically involve muscles in the extremities that do not reflect the delicate and complex architecture of craniofacial muscles. Passipieri et al. report in a recent article the development of a pre-clinical model of volumetric muscle loss in the latissimus dorsi of rats, which they claim to be of similar size and architecture to the human orbicularis oris muscle. They apply the model to investigate the efficacy of tissue engineered muscle constructs generated through bioreactor-driven mechanical stimulation of muscle progenitor cells cultured on bladder acellular matrix. The tissue engineered muscle constructs resulted in improved functional recovery as compared to no repair and bladder acellular matrix alone. In parallel, the group developed a computational model, which provided biomechanical insight into the defect itself and the functional recovery observed. The craniofacially-relevant pre-clinical model combined with the computational methods provide a powerful toolset to enable informed development of tissue engineering strategies targeted to address volumetric muscle loss in the craniomaxillofacial complex.
In Silico and In Vivo Studies Detect Functional Repair Mechanisms in a Volumetric Muscle Loss Injury.
Passipieri JA, Hu X, Mintz E, Dienes J, Baker HB, Wallace CH, Blemker SS, Christ GJ. Tissue Eng Part A. 2019 Mar 18. doi: 10.1089/ten.tea.2018.0280. [Epub ahead of print]