Proximal humerus fracture (PHF) treatment remains challenging. Multiple therapy options exist, and the optimal choice of management has been increasingly discussed in the literature. The aim of this study was to (1) analyze trends in the propensity of proximal humerus fracture treatments and (2) compare complication rates after joint replacement, surgical repair, and non-surgical treatment in terms of mechanical complications, union failure, and infection rates. In this cross-sectional study, patients aged 65 years or older with proximal humerus fractures occurring between 1 January 2009 and 31 December 2019 were identified from Medicare physician service claims records. The Kaplan–Meier method with the Fine and Gray adjustment was used to calculate the cumulative incidence rates for malunion/nonunion, infection, and mechanical complications for the following treatment categories: shoulder arthroplasty, open reduction and internal fixation (ORIF), and non-surgical treatment, respectively. Semiparametric Cox regression was performed incorporating 23 demographic, clinical, and socioeconomic covariates to determine risk factors. Between 2009 through 2019, conservative procedures decreased by 0.9%. ORIF procedures decreased from 9.51% (95% CI: 8.7–10.4) to 6.95% (95% CI: 6.2–7.7), whereas shoulder arthroplasties rose from 1.99% (95% CI: 1.6–2.4), to 5.45% (95% CI: 4.8–6.2). PHFs managed through ORIF were associated with higher union failure rates compared to conservatively treated fractures (HR = 1.31, 95% CI: 1.15–1.5, p < 0.001). The risk of developing an infection was increased after joint replacement compared to ORIF (2.66% vs. 1.09%, HR = 2.09, 95% CI: 1.46–2.98, p < 0.001). Mechanical complications were more common after joint replacement (6.37% vs. 4.85%, HR = 1.66, 95% CI: 1.32–2.09, p < 0.001). Complication rates differed significantly across treatment modalities. This should be considered when choosing a management procedure. Vulnerable elderly patient cohorts could be identified, and the optimization of modifiable risk factors might lead to a decrease of complication rates in both surgically and non-surgically treated patients.

Background: The management of pelvic fractures is a significant challenge. Surgical site infection can result in the need for revision surgery, cause functional impairment, and lead to a prolonged length of stay and increased treatment costs. Although reports on fracture-related infection (FRI) after pelvic fracture fixation are sparsely reported in the literature, it is a serious complication. This study analysed patients with FRIs after pelvic fracture regarding patient characteristics, treatment strategies, and an evaluation of risk factors for FRI. Methods: In this retrospective single-centre study, FRI was diagnosed based on clinical symptoms of infection and a positive culture of a bacterial infection. Depending on the severity and acuteness of the infection, osseous stabilization was restored either via implant retention (stable implant, no osteolysis), exchange (loose implant or bony defect), or external fixation (recurrence of infection after prior implant retaining revision). Healing of infection was defined as no sign of recurring infection upon clinical, radiological, and laboratory examination in the last follow-up visit. Results: The FRI rate in our patient population was 7.5% (24/316). In 8/24 patients, the FRI occurred within the first three weeks after initial surgery (early) and 16/24 presented with a late onset of symptoms of FRI. A strategy of debridement, antibiotics, and implant retention (DAIR) was successful in 9/24 patients with FRI after pelvic fracture. A total of 10 patients required an exchange of osteo-synthetic implants, whereof three were exchanged to an external fixator. In five patients, we removed the implant because the fracture had already consolidated at the time of revision for infection. A total of 17/24 patients had a poly-microbial infection after a pelvic fracture and 3/24 patients died from post-traumatic multi-organ failure within the first 6 months after trauma. There were no cases of persistent infection within the remaining 21 patients. Conclusions: Although poly-microbial infection is common in FRI after pelvic fracture, the recurrence rate of infection is relatively low. A complex pelvic trauma with significant soft tissue injury is a risk factor for recurrent infection and multiple revisions. A strategy of DAIR can be successful in patients with a stable implant. In cases with recurrent infection or an unstable fracture site, the exchange of implants should be considered.

In vitro chondrogenically differentiated mesenchymal stem cells (MSCs) have a tendency to undergo hypertrophy, mirroring the fate of transient “chondrocytes” in the growth plate. As hypertrophy would result in ossification, this fact limits their use in cartilage tissue engineering applications. During limb development, retinoic acid receptor (RAR) signaling exerts an important influence on cell fate of mesenchymal progenitors. While retinoids foster hypertrophy, suppression of RAR signaling seems to be required for chondrogenic differentiation. Therefore, we hypothesized that treatment of chondrogenically differentiating hMSCs with the RAR inverse agonist, BMS204,493 (further named BMS), would attenuate hypertrophy. We induced hypertrophy in chondrogenic precultured MSC pellets by the addition of bone morphogenetic protein 4. Direct activation of the RAR pathway by application of the physiological RAR agonist retinoic acid (RA) further enhanced the hypertrophic phenotype. However, BMS treatment reduced hypertrophic conversion in hMSCs, shown by decreased cell size, number of hypertrophic cells, and collagen type X deposition in histological analyses. BMS effects were dependent on the time point of application and strongest after early treatment during chondrogenic precultivation. The possibility of modifing hypertrophic cartilage via attenuation of RAR signaling by BMS could be helpful in producing stable engineered tissue for cartilage regeneration.

Background and Objectives: Abdominal trauma among severely injured patients with an injury severity score (ISS) of 16 and above can lead to potentially life-threatening injuries that might need immediate surgical intervention. Traumatic injuries to the diaphragm (TID) are a challenging condition often accompanied by other injuries in the thoracoabdominal region. Materials and Methods: We retrospectively analyzed the occurrence and clinical course of TID among severely injured patients treated at our center between 2008 and 2019 and compared them to other groups of severely injured patients without TID. Results: Thirty-five patients with TID and a median ISS of 41 were treated in the period mentioned above. They were predominantly middle-aged men and mostly victims of blunt trauma as a consequence of motor vehicle accidents. A total of 70.6% had left-sided TID, and in 69.6%, the size of defect was larger than 10 cm. The diagnosis was made with computed tomography (CT) in 68.6% of the cases, while in 25.8%, it was made intraoperatively or delayed by a false-negative initial CT scan, and in 5.7%, an intraoperative diagnosis was made without preoperative CT imaging. Surgical repair was mostly conducted via laparotomy, performing a direct closure with continuous suture. A comparison to 191 patients that required laparotomy for abdominal injuries other than TID revealed significantly higher rates of concomitant injuries to several abdominal organs among patients suffering from TID. Compared to all other severely injured patients treated in the same period (n = 1377), patients suffering from TID had a significantly higher median ISS and a longer mean duration of hospital stay. Conclusions: Our findings show that TID can be seen as an indicator of particularly severe thoracoabdominal trauma that requires increased attention from the treatment team so as not to miss relevant concomitant injuries that require immediate intervention.

Objective: According to current recommendations, large cartilage defects of the hip over 2 cm² are suggested to undergo autologous chondrocyte transplantation (ACT), while small defects should be treated with microfracture. We investigated if patients with small chondral defects of the hip joint (≤100 mm²) actually benefit from microfracture. Design: In this retrospective multicenter cohort study 40 patients with focal acetabular cartilage defects smaller than 100 mm² and of ICRS grade ≥2 caused by femoroacetabular impingement were included. Twenty-six unrandomized patients underwent microfracture besides treatment of the underlying pathology; in 14 patients cartilage lesions were left untreated during arthroscopy. Over a mean follow-up of 28.8 months patient-reported outcome was determined using the iHOT33 (international hip outcome tool) and the VAS (visual analog scale) for pain. Results: The untreated group showed a statistically significant improvement of the iHOT33 after 12 (p = 0.005), 24 (p = 0.019), and 36 months (p = 0.002) compared to the preoperative score, whereas iHOT33 in the microfracture group did not reveal statistically significant changes over time. There was no significant difference between both groups on any time point. Regarding pain both groups did not show a significant improvement over time in the VAS. Conclusion: The subjective outcome of patients with small cartilage defects of the hip (≤100 mm²) improves 12 months after arthroscopic FAIS surgery without any cartilage treatment. However, no improvement could be seen after microfracture. Therefore, a reserved surgical treatment for small cartilage defects of the hip under preservation of the subchondral bone is recommended especially if a simultaneous impingement correction is performed.

Purpose: Articular cartilage defects are a prevalent consequence of femoroacetabular impingement (FAI) in young active patients. In accordance with current guidelines, large chondral lesions of the hip joint over 2 cm² are recommended to be treated with matrix-associated, autologous chondrocyte transplantation (MACT); however, the conditions in the hip joint are challenging for membrane-based MACT options. Injectable MACT products can solve this problem. The purpose of the trial was to assess clinical and radiological outcomes 24 months after injectable MACT of focal chondral lesions caused by FAI. Methods: We present data of 21 patients with focal cartilage defects of the hip [3.0 ± 1.4 cm² (mean ± SD)], ICRS Grade III and IV caused by CAM-type impingement, who underwent arthroscopic MACT (NOVOCART^® Inject) and FAI correction. The outcome was evaluated with the patient-reported outcome instruments iHOT33 and EQ-5D-5L (index value and VAS), whilst graft morphology was assessed based on the MOCART score over a follow-up period of 24 months. Results: The iHOT33 score increased significantly from 52.9 ± 21.1 (mean ± SD) preoperatively to 85.8 ± 14.8 (mean ± SD; p < 0.0001) 24 months postoperatively. The EQ-5D-5L index value (p = 0.0004) and EQ-5D VAS (p = 0.0006) showed a statistically significant improvement as well. MRI evaluation after 24 months showed successful integration of the implant in all patients with a complete defect filling in 11 of 14 patients. Conclusions: Injectable MACT for the treatment of full-thickness chondral lesions of the hip joint due to FAI in combination with FAI correction improved symptoms, function, and quality of life in the treated cohort. Alongside the treatment of the underlying pathology by the FAI correction, the developed cartilage defect can be successfully repaired by MACT, which is of considerable clinical relevance.