Comparable Outcomes Between Native and Periprosthetic Fractures of the Distal Femur.

Despite the rising prevalence of arthroplasty and aging population, limited data exist regarding differences in periprosthetic fracture clinical outcomes compared with native counterparts. This study compares differences in hospital treatment, morbidity, and mortality associated with periprosthetic distal femur fractures at an urban level 1 trauma center. We retrospectively reviewed all adult AO/OTA type 33 fractures (526) that presented to our institution between 2009 and 2018. In total, 54 native and 54 periprosthetic fractures were matched by age and gender. We recorded demographics, operative measures, length of stay (LOS), discharge disposition, and mortality. We used McNemar's and paired t-tests for analysis where appropriate (p < 0.05) (IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY; IBM Corp.). The average age at injury was 74 years ± 12 (native) compared with 73 years ± 12 (periprosthetic). After 1:1 matching, the groups had similar body mass index (31.01 vs. 32.98, p = 0.966 for native and periprosthetic, respectively) and mechanisms of injury with 38 native and 44 periprosthetic (p = 0.198) fractures from low-energy falls. Both groups had 51/54 fractures managed with open reduction internal fixation with a locking plate. The remaining were managed via amputation or intramedullary nail fixation. Mean operative time (144 minutes (±64) vs. 132 minutes (±62), p = 0.96) and estimated blood loss (319 mL (±362) vs. 289 mL (±231), p = 0.44) were comparable between the native and periprosthetic groups, respectively. LOS: 9 days ± 7 (native) versus 7 days ± 5 (periprosthetic, p = 0.31); discharge disposition (to skilled nursing facility/rehab): n = 47 (native) versus n = 43 (periprosthetic, p = 0.61); and mortality: n = 6 (native) versus n = 8 (periprosthetic, p = 0.55). No significant differences were observed. We found no statistical differences in morbidity and mortality in periprosthetic distal femur fractures treated over 10 years at a level 1 trauma center. Native and periprosthetic AO/OTA type 33 distal femur fractures are serious injuries with similar outcomes at a level 1 trauma center.

Treatment of compartment syndrome: transverse fasciotomy as an adjunct to longitudinal dermatofasciotomy: an in vitro study.

OBJECTIVE: This study describes a previously unpublished technique for compartment release that combines adjunctive transverse fasciotomies with a limited longitudinal dermatofasciotomy and compares its efficacy with a standard extensile longitudinal dermatofasciotomy. DESIGN: Limited 10-cm longitudinal dermatofasciotomies were performed bilaterally on 14 cadaveric specimens (28 legs). Next, we performed transverse fasciotomies on 1 limb and performed extensions of the longitudinal incision on the contralateral limb. Subsequent changes in compartment pressures were recorded after each release. Two-tailed paired and unpaired Student t tests were performed for statistical analysis with significance set at P < 0.05. SETTING: Anatomy laboratory. RESULTS: After a 10-cm longitudinal dermatofasciotomy, the average compartment pressure was 17 +/- 7.1 mm Hg proximally and 15.5 +/- 7.4 mm Hg distally. With an extensile 16-cm longitudinal incision, a significant decrease in compartment pressure was seen both proximally (6.5 +/- 3.1 mm Hg) and distally (4.7 +/- 4.7 mm Hg). With adjunctive transverse fasciotomies, a significant reduction in compartment pressure also was observed proximally (6.9 +/- 6.1 mm Hg) and distally (6.1 +/- 5.4 mm Hg). There was no statistically significant difference in compartment pressures between an extensile 16-cm incision and 10-cm incision combined with transverse fasciotomies both proximally and distally (P = 0.84 and P = 0.5, respectively). CONCLUSIONS: A combined approach of transverse fasciotomies with a limited longitudinal dermatofasciotomy in this in vitro compartment syndrome study is as effective as a standard 16-cm longitudinal release in the anterior compartment of this cadaveric leg model.

Subtrochanteric fixation stability depends on discrete fracture surface points.

Fixation of subtrochanteric femur fractures may present complications, including malunion, delayed union, or nonunion, and is thought to be related to early fracture stability. To examine the initial stability of subtrochanteric fracture fixation, we investigated construct stiffness, interfragmentary gaps, and overall and point-wise interfragmentary motion (ie, axial and shear displacements) in synthetic composite femurs fixed with a cephalomedullary nail or condylar blade plate. Simulated stable and unstable subtrochanteric femur fractures were created in composite femurs, anatomically reduced, fixed with either a long Gamma nail or a blade plate, and subjected to combined axial, bending, and torsional loading. The long Gamma nail group consistently showed greater displacement magnitudes than the blade plate group; these differences included axial and shear displacement magnitudes in the stable fracture group and shear displacement magnitudes in the unstable fracture group. Overall differences in fixation stability were dependent on discrete points around the periphery of the contiguous fracture surfaces, especially in the unstable fracture group. These differences in interfragmentary motion patterns between implant constructs were detected despite the lack of difference in combined axial, bending, and torsional construct stiffness or initial interfragmentary gap.