Simultaneous septic arthrodesis of the tibiotalar and subtalar joints with the Ilizarov external fixator

$\bf Purpose$ Treatment of joint destruction of the tibiotalar and subtalar joints caused by acute or chronic infections in compromised hosts is a challenging problem. In these cases, simultaneous septic arthrodesis with the use of the Ilizarov external fixator represents a possible alternative to amputation. This case series presents the results and complications of patients with acute or chronic infection of the tibiotalar and subtalar joints. $\bf Methods$ Between 2005 and 2015, 13 patients with acute or chronic infections were treated by simultaneous single-stage debridement/arthrodesis of the tibiotalar and subtalar joints. In seven patients, there was a florid infection with fistula formation and soft tissue defects, and in six patients, there was chronic osteomyelitis with closed soft tissue. In addition to the demographic data, the time spent in the fixator, the major and minor complications and the endpoint of consolidation were reviewed. $\bf Results$ The mean time spent in the fixator was 18 (min 15, max 26) weeks. The mean follow-up time for nine patients was 100 (min 3, max 341) weeks. Complete osseous consolidation of both the tibiotalar and subtalar joints was achieved in 10 patients (77%). In three (23%) patients, there was complete consolidation of one of the joints and partial consolidation of the other joint. $\bf Conclusion$ The Ilizarov external fixator allows for simultaneous arthrodesis of the tibiotalar and subtalar joints in septic joint destruction. However, the healing rates are below the rates reported in the literature for isolated tibiotalar or tibiocalcaneal arthrodesis in comparable clinical situations

HAL training in spinal cord injured patients

To provide a summary and overview of the use of Hybrid Assistive Limb in spinal cord injured patients over the past 10 years. A review of the literature was performed via Web of Science and PubMed using the search terms "Hybrid assistive limb" or "HAL" or "wearable robot" or "exoskeleton" and "SCI" or "spinal cord injury" by two of the authors. Relevant articles were then studied in full text. Our review of the literature found 21 articles that met the inclusion criteria of this narrative review including 344 participants. Articles were sorted into two general categories: (1) clinical trials, and (2) single-case or two-case reports. The vast majority of patients improved functionally, showing increased walking distances, walking speeds, and endurance. In addition, a variety of other advances were described, such as temporary decrease in spasticity, improvement in bladder and bowel management, pain reduction, and change in muscle activity. Even though there is no uniform application of HAL training in people living with SCI the current study situation suggests that many patients could benefit from this innovative training within their means

Poor outcome of octogenarians admitted to ICU due to periprosthetic joint infections

$\bf Background$ Even though surgical techniques and implants have evolved, periprosthetic joint infection (PJI) remains a serious complication leading to poor postoperative outcome and a high mortality. The literature is lacking in studies reporting the mortality of very elderly patients with periprosthetic joint infections, especially in cases when an intensive care unit (ICU) treatment was necessary. We therefore present the first study analyzing patients with an age 80 and higher suffering from a periprosthetic joint infection who had to be admitted to the ICU. $\bf Methods$ All patients aged 80 and higher who suffered from a PJI (acute and chronic) after THR or TKR and who have been admitted to the ICU have been included in this retrospective, observational, single-center study. $\bf Results$ A total of 57 patients met the inclusion criteria. The cohort consisted of 24 males and 33 females with a mean age of 84.49 ($\pm$ 4.0) years. The mean SAPS II score was 27.05 ($\pm$ 15.7), the mean CCI was 3.35 ($\pm$ 2.28) and the most patient had an ASA score of 3 or higher. The PJI was located at the hip in 71.9% or at the knee in 24.6%. Two patients (3.5%) suffered from a PJI at both locations. Sixteen patients did not survive the ICU stay. Non-survivors showed significantly higher CCI (4.94 vs. 2.73; $\it p$ = 0.02), higher SAPS II score (34.06 vs. 24.32; $\it p$ = 0.03), significant more patients who underwent an invasive ventilation (132.7 vs. 28.1; $\it p$ = 0.006) and significantly more patients who needed RRT (4.9% vs. 50%; $\it p$ < 0.001). In multivariate analysis, RRT (odds ratio (OR) 15.4, CI 1.69–140.85; $\it p$ = 0.015), invasive ventilation (OR 9.6, CI 1.28–71.9; $\it p$ = 0.028) and CCI (OR 1.5, CI 1.004–2.12; $\it p$ = 0.048) were independent risk factors for mortality. $\bf Conclusion$ Very elderly patients with PJI who needs to be admitted to the ICU are at risk to suffer from a poor outcome. Several risk factors including a chronic infection, high SAPS II Score, high CCI, invasive ventilation and RRT might be associated with a poor outcome

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

Navigated iliac screw placement may reduce radiation and OR time in lumbopelvic fixation of unstable complex sacral fractures

$\bf Purpose$ Instability of the posterior pelvic ring may be stabilized by lumbopelvic fixation. The optimal osseous corridor for iliac screw placement from the posterior superior iliac spine to the anterior inferior iliac spine requires multiple ap- and lateral-views with additional obturator-outlet and -inlet views. The purpose of this study was to determine if navigated iliac screw placement for lumbopelvic fixation influences surgical time, fluoroscopy time, radiation exposure, and complication rates. $\bf Methods$ Bilateral lumbopelvic fixation was performed in 63 patients. Implants were inserted as previously described by Schildhauer. A passive optoelectronic navigation system with surface matching on L4 was utilized for navigated iliac screw placement. To compare groups, demographics were assessed. Operative time, fluoroscopic time, and radiation were delineated. $\bf Results$ Conventional fluoroscopic imaging for lumbopelvic fixation was performed in 32 patients and 31 patients underwent the procedure with navigated iliac screw placement. No differences were found between the groups regarding demographics, comorbidities, or additional surgical procedures. Utilization of navigation led to fluoroscopy time reduction of more than 50% (3.2 vs. 8.6 min.; $\it p$ < 0.001) resulting in reduced radiation (2004.5 vs. 5130.8 Gy*$cm^{2}$; $\it p$ < 0.001). Operative time was reduced in the navigation group (176.7 vs. 227.4 min; $\it p$ = 0.002) despite the necessity of additional surface referencing. $\bf Conclusion$ For iliac screws, identifying the correct entry point and angle of implantation requires detailed anatomic knowledge and multiple radiographic views. In our study, additional navigation reduced operative time and fluoroscopy time resulting in a significant reduction of radiation exposure for patients and OR personnel

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

Comparison of lumbopelvic fixation and iliosacral screw fixation for the treatment of bilateral sacral fractures

$\bf Background$ Bilateral sacral fractures result in traumatic disruption of the posterior pelvic ring. Treatment for unstable posterior pelvic ring fractures should aim for fracture reduction and rigid fixation to facilitate early mobilization. Iliosacral screw fixation (ISF) and lumbopelvic fixation (LPF) were recommended for the treatment of these injuries. No algorithm or gold standard exists for surgery of these fractures. $\bf Purpose$ The purpose of this study was to evaluate the differences between ISF and LPF in bilateral sacral fractures regarding intraoperative procedures, complications and postoperative mobilization. The secondary aim was to determine whether demographics influence surgical treatment. $\bf Methods$ Over a 4-year period (2016–2019), 188 consecutive patients with pelvic ring injuries were treated at one academic level 1 trauma center and retrospectively identified. Fractures were classified according to the AO/OTA classification system. Seventy-seven patients were treated with LPF or ISF in combination with internal fixation of pubic rami fractures and could be included in this study. Comparisons were made between demographic and perioperative data. Infection, hematoma and hardware malpositioning were used as complication variables. Mobilization with unrestricted weight bearing was used as outcome variable. Follow-up was at least 6 months postoperatively. $\bf Results$ Operative stabilization of bilateral posterior pelvic ring injuries was performed in 77 patients. Therefore, 29 patients (females 59%) underwent LPF whereas 48 patients (females 83%) had bilateral ISF. The ISF group was older (76 yrs.) compared to the LPF group (62 yrs.) ($\it p$ = 0.001), but no differences regarding BMI or comorbidities were detected. Time for surgery was reduced for patients who were treated with ISF compared to lumbopelvic fixation (73 min vs. 165 min; respectively, $\it p$ < 0.001). But this did not result in reduced fluoroscopic time or radiation exposure. Overall complication rate was not different between the groups. Patients with LPF had a greater length of stay ($\it p$ = 0.008) but were all weight bearing as tolerated when discharged ($\it p$ < 0.001). $\bf Conclusion$ Bilateral posterior pelvic ring injuries of the sacrum can be sufficiently treated by LPF or ISF. LPF allows immediate weight bearing which may benefit younger patients and patients with an elevated risk for pneumonia or other pulmonary complications. Treatment with ISF reduces operative time, length of stay and postoperative wound infection. Elderly patients may be better suited for treatment with ISF if there is concern that the patient may not tolerate the increased operative time

Improved physiological gait in acute and chronic SCI patients after training with wearable cyborg hybrid assistive limb

In recent years robotic devices became part of rehabilitation offers for patients suffering from Spinal Cord Injury (SCI) and other diseases. Most scientific publications about such devices focus on functional outcome. The aim of this study was to verify whether an improvement in physiological gait can be demonstrated in addition to the functional parameters after treatment with neurological controlled HAL® Robot Suit. Fifteen subjects with acute (12 months since injury, $\it n$ = 10) incomplete paraplegia (AIS B, $\it n$ = 0/AIS C, $\it n$ = 2/AIS D, $\it n$ = 8) or complete paraplegia (AIS A, $\it n$ = 5) with zones of partial preservation participated. Subjects underwent a body weight supported treadmill training for five times a week over 12 weeks using HAL®. At baseline and at the end of the study a gait analysis was performed and additional functional parameters such as 10-Meter-Walk-Test, Timed-Up-and-Go-Test, 6-Minutes-Walk-Test, and WISCI II score were collected. Results were evaluated for whole group and individually for acute and chronic subgroups. All functional parameters improved. Differences were also found in physiological parameters such as phases of gait cycle and accompanied by significant improvement in all spatiotemporal and gait phase parameters. The presented study shows signs that an improvement in physiological gait can be achieved in addition to improved functional parameters in patients with SCI after completing 12-week training with HAL®

Functional outcome of traumatic spinopelvic instabilities treated with lumbopelvic fixation

The aim of this study was to assess the functional outcome after lumbopelvic fixation (LPF) using the SMFA (short musculoskeletal functional assessment) score and discuss the results in the context of the existing literature. The last consecutive 50 patients who underwent a LPF from January 1st 2011 to December 31st 2014 were identified and administered the SMFA-questionnaire. Inclusion criteria were: (1) patient underwent LPF at our institution, (2) complete medical records, (3) minimum follow-up of 12 months. Out of the 50 recipients, 22 questionnaires were returned. Five questionnaires were incomplete and therefore seventeen were included for analysis. The mean age was 60.3 years (32–86 years; 9m/8f) and the follow-up averaged 26.9 months (14–48 months). Six patients (35.3%) suffered from a low-energy trauma and 11 patients (64.7%) suffered a high-energy trauma. Patients in the low-energy group were significantly older compared to patients in the high-energy group (72.2 vs. 53.8 years; $\it {p}$ = 0.030). Five patients (29.4%) suffered from multiple injuries. Compared to patients with low-energy trauma, patients suffering from high-energy trauma showed significantly lower scores in "daily activities" (89.6 vs. 57.1; $\it {p}$ = 0.031), “mobility” (84.7 vs. 45.5; $\it {p}$ = 0.015) and "function" (74.9 vs. 43.4; $\it {p}$ = 0.020). Our results suggest that patients with older age and those with concomitant injuries show a greater impairment according to the SMFA score. Even though mostly favorable functional outcomes were reported throughout the literature, patients still show some level of impairment and do not reach normative data at final follow-up