Rate of progressive healing with a carbon-fiber orthosis in cases of partial union and nonunion after ankle arthrodesis using the Ilizarov external fixator

$\bf Background$ The Ilizarov fixator is a popular device for treating arthrodesis of the ankle joint in complex situations. However, the therapy can fail, with nonunion or partial union that might not be load stable. There is the possibility of follow-up surgery or extended wearing of the fixator. Full weight bearing with a carbon orthosis remains another treatment option, which has not yet been investigated. The aim of the study was to determine the rate of progress that can be obtained with a carbon orthosis in cases of partial union or nonunion after fixator removal. $\bf Methods$ In this retrospective observational study thirty-three patients received a carbon orthosis after fixator removal due to nonunion or partial union. All patients were allowed to walk with the orthosis under full load. The consolidation rate was determined radiologically and compared with the imaging data obtained during the last follow-up. In addition to demographic data, the Foot and Ankle Ability Measure and pain using a numeric rating scale were determined. Nine patients had to be excluded due to insufficient follow-up, and finally $\it n$ = 24 patients were included in the study. $\bf Results$ The average duration of fixator use was 21 weeks (range 15–40 weeks), and the total average follow-up after removal of the fixator was 16 months (range 4- 56). For 14 (58.33%) patients, there was a further increase in consolidation with the orthosis after the fixator was removed. $\bf Conclusion$ The results show that if there is only partial union or nonunion, further consolidations can be achieved after the application of a carbon orthosis. In a difficult patient population, using an orthosis should therefore be attempted to avoid unnecessary revision operations

Medial augmentation plating of aseptic distal femoral nonunions

$\bf Background$ Distal femur nonunions are well-recognized contributors to persistent functional disability, with limited data regarding their treatment options. In the current study, we asked whether additional medial augmentation plating is a feasible treatment option for patients with aseptic distal femoral nonunion and intact lateral implants. $\bf Methods$ We conducted a single-center, retrospective study including 20 patients treated for aseptic distal femoral nonunion between 2002 and 2017. The treatment procedure included a medial approach to the distal femur, debridement of the nonunion site, bone grafting and medial augmentation plating utilizing a large-fragment titanium plate. Outcome measures were bone-related and functional results, measured by the Hospital for Special Surgery Knee Rating Scale (HSS) and the German Short Musculoskeletal Function Assessment questionnaire (SMFA-D). $\bf Results$ Eighteen of 20 nonunions showed osseous healing at 8.16 $\pm$ 5.23 (range: 3–21) months after augmentation plating. Regarding functional results, the mean HSS score was 74.17 $\pm$ 11.12 (range: 57–87). The mean SMFA-D functional index was 47.38 $\pm$ 16.78 (range 25.74–71.32) at the last follow-up. Index procedure-associated complications included two cases of persistent nonunion and one case of infection. $\bf Conclusions$ According to the assessed outcome measures, augmentation plating is a feasible treatment option, with a high proportion of patients achieving bony union and good functional outcomes and a few patients experiencing complications

Microbial findings and the role of difficult-to-treat pathogens in patients with periprosthetic infection admitted to the intensive care unit

Little is known about patients with Periprosthetic Joint Infection (PJI) admitted to the Intensive Care Unit (ICU). The purpose of this study was threefold: i) To report the microbiological findings of ICUpatients with PJI. ii) To compare the clinical data between Difficult-To-Treat (DTT) and non-DTT PJI. iii) To identify risk factors for mortality. This is a retrospective study from a tertiary healthcare center in Germany from 2012-2016. A total of 124 patients with 169 pathogens were included. The most common bacteria were $\textit {Staphyloccous aureus}$ (26.6%), $\textit {Staphyloccus epidermidis}$ (12.4%), $\textit {Enterococci ssp.}$ and $\textit {Escherichia coli}$ (respectively 9.4%). DTT PJI was diagnosed in 28 patients (22.6%). The main pathogens of DTT PJI were $\textit {Staphylococus epidermidis}$ (14.5%), $\textit {Escherichia coli}$ (12.7%), $\textit {Staphylococcus aureus}$ and $\textit {Candida spp.}$ (respectively 9.1%). Polymicrobial PJI, number of pathogens, ICU stay and mortality were significantly differrent between DTT PJI and non-DTT PJI (p$\leq$0.05). Multivariate logistic regression identified prolonged ICU stay and DTT PJI as risk factors for mortality. In conclusion, we suggest, that the term of DTT pathogens is useful for the intensivist to assess the clinical outcome in ICU-patients with PJI

Tibiocalcaneal arthrodesis using the Ilizarov fixator in compromised hosts

$\bf Introduction$ Salvage of joint destruction of the tibiotalar and subtalar joint with necrosis or infection of the talus in compromised hosts is a challenging problem. In these cases, tibiocalcaneal arthrodesis using the Ilizarov external fixator represents a possible alternative to amputation. This retrospective study presents the results and complications of this salvage procedure. $\textbf {Materials and methods}$ Between 2005 and 2015, 19 patients were treated with tibiocalcaneal arthrodesis using the Ilizarov external fixator. Ten patients received tibiocalcaneal arthrodesis due to an acute or chronic infection with joint destruction. The other nine patients presented posttraumatic necrosis of the talus or Charcot arthropathy. In addition to demographic data, the time spent in the fixator, the major and minor complications and the endpoint of the consolidation were evaluated retrospectively. Furthermore, clinical outcomes were measured using the modified American Orthopedic Foot and Ankle Society (AOFAS) score. $\bf Results$ The average time spent in the fixator was 22 (range 14–34) weeks. The average follow-up in 17 patients was 116 (range 4–542) weeks. Two patients were lost to follow-up. Complete osseous consolidation was achieved in 14 out of 19 patients. One patient presented partial consolidation, and in four patients, pseudarthrosis could be detected. The mean modified AOFAS score at the final follow-up was 53 out of 86 possible points. $\bf Conclusion$ Tibiocalcaneal arthrodesis using the Ilizarov fixator is a possible salvage procedure even in compromised hosts. However, the healing rates are below the rates reported in the literature for tibiotalar arthrodesis in comparable clinical situations