Search

Background: Vaginal (re)construction can greatly improve the quality of life of indicated patients. If primary vaginoplasty fails, multiple surgical approaches exist for revision. The authors compared surgical results of laparoscopic intestinal versus full-thickness skin graft revision vaginoplasty., Methods: A retrospective chart review of patients who underwent revision vaginoplasty at the authors' institution was conducted. Patient demographics, surgical characteristics, complications, hospitalization, reoperations, and neovaginal depth for both surgical techniques were recorded and compared., Results: The authors studied a consecutive series of 50 transgender and three biological women who underwent revision vaginoplasty, of which 21 were laparoscopic intestinal and 32 were perineal full-thickness skin graft vaginoplasties, with a median clinical follow-up of 3.2 years (range, 0.5 to 19.7 years). Patient demographics did not differ significantly. There was no mortality. Two intraoperative rectal perforations (10 percent) occurred in the intestinal group versus six (19 percent) in the full-thickness skin graft group. Operative time was shorter for the full-thickness skin graft vaginoplasty group (131 ± 35 minutes versus 191 ± 45 minutes; p < 0.01). Hospitalization length did not differ significantly. Successful vaginal (re)construction was achieved in 19 intestinal (91 percent) and 26 full-thickness skin graft (81 percent) vaginoplasty procedures. A deeper neovagina was achieved with intestinal vaginoplasty (15.9 ± 1.4 cm versus 12.5 ± 2.8 cm; p < 0.01)., Conclusions: Both laparoscopic intestinal and full-thickness skin graft vaginoplasty can be used as secondary vaginal reconstruction. Intraoperative and postoperative complications do not differ significantly, but rectal perforation was more prevalent in the full-thickness skin graft vaginoplasty group. Although the operative time of laparoscopic intestinal vaginoplasty is longer, adequate neovaginal depth was more frequently achieved than in secondary perineal full-thickness skin graft vaginoplasty., Clincal Question/level of Evidence: Therapeutic, III.

Study Design: A study of lumbar interbody fusion using polylactic acid-based bioresorbable fusion cages in a goat model., Objective: To evaluate the effect of polylactic acid polymer composition, and internal stabilization on the rate and quality of interbody fusion., Summary of Background Data: A spinal cage should provide an appropriate biomechanical environment to facilitate interbody fusion. Previous studies have shown that bioresorbable polylactic acid-based cages can provide adequate stability for spinal fusion. However, at present and to our knowledge, the best bioresorbable materials, optimal cage stiffness, and desired period over which the cage should biodegrade are unknown., Methods: Interbody fusions were performed at L3-L4 level in 35 skeletally mature Dutch milk goats. Titanium and poly-L-lactide-CO-D,L-lactide (PLDLLA) cages were implanted at random as stand-alone cages. In addition, PLDLLA cages were implanted with anterior fixation. The goats were euthanized at 3, 6, or 12 months. Radiographic, magnetic resonance imaging, histologic, and histomorphometric analyses were performed on retrieved segments. Chemical analysis was used to assess degradation of the retrieved PLDLLA cages. Beforehand, chemical and mechanical degradation of the PLDLLA cages were assessed in vitro., Results: At 3 months, bone graft was almost completely remodeled. Endochondral bone formation was observed in all specimens. At 6 months, 50% of the PLDLLA stand-alone cages and 83% of the PLDLLA anterior fixation cages were fused. At 12 months, 38% of the PLDLLA stand-alone and 83% of the titanium cages realized fusion. A very mild and dispersed foreign body reaction was seen in all PLDLLA specimens. E-beam sterilized PLDLLA cages degraded more rapidly in vivo as compared to both, PLDLLA cages in vitro, and ethylene oxide sterilized poly-L-lactic acid cages in vivo., Conclusions: Within the 3-6-month period, PLDLLA stand-alone cages provided insufficient mechanical stability, which manifested as cracking and deformation of the cages and lower fusion rates. This result implies that within this time, additional stabilization is required; supplemental internal fixation proved sufficient to obtain successful fusion. In all cases, only a mild host response was seen, indicating good biocompatibility.

Study Design: An in vitro mechanical study on porcine motion segments., Objectives: To test the validity of in vitro studies of the flow-related mechanics of the intervertebral disc and, in particular, to investigate whether fluid flows back into the disc during unloading after a loading cycle., Summary of Background Data: In vivo studies show both the inflow and outflow of fluid in the intervertebral disc. The resistance to flow out of the disc is higher than to inflow. The fluid flow is regulated via unbalance between the external load and the osmotic pressure of the nucleus pulposus., Materials: There were 8 porcine lumbar motion segments (without posterior elements) and 8 isolated discs tested in a physiologic saline bath (39 degrees C). The specimens were preloaded at 0.025 MPa for 15 minutes. Three 15-minute loading periods at 2.0 MPa were applied, each followed by an unloading period of 30 minutes. Loads, axial displacements, and nucleus pressure were recorded online., Results: Over the 3 loading and unloading periods, all specimens showed a net loss of height and mass. The time series of specimen height during the 3 unloading periods showed virtually identical responses. The pressure in the nucleus decreased in the subsequent loading periods and showed no increase during unloading., Conclusion: The data show the limitations of an in vitro model for studying fluid flow-related intervertebral disc mechanics. During loading, outflow of fluid occurred, but inflow appears to be virtually absent during unloading. Poro-elastic behavior cannot be reproduced in an in vitro model.