Meniscal tears in the avascular zone have a poor self-healing potential, however partial meniscectomy predisposes the knee for early osteoarthritis. Tissue engineering with mesenchymal stem cells and a hyaluronan collagen based scaffold is a promising approach to repair meniscal tears in the avascular zone. 4 mm longitudinal meniscal tears in the avascular zone of lateral menisci of New Zealand White Rabbits were performed. The defect was left empty, sutured with a 5-0 suture or filled with a hyaluronan/collagen composite matrix without cells, with platelet rich plasma or with autologous mesenchymal stem cells. Matrices with stem cells were in part precultured in chondrogenic medium for 14 days prior to the implantation. Menisci were harvested at 6 and 12 weeks. The developed repair tissue was analyzed macroscopically, histologically and biomechanically. Untreated defects, defects treated with suture alone, with cell-free or with platelet rich plasma seeded implants showed a muted fibrous healing response. The implantation of stem cell-matrix constructs initiated fibrocartilage-like repair tissue, with better integration and biomechanical properties in the precultured stem cell-matrix group. A hyaluronan-collagen based composite scaffold seeded with mesenchymal stem cells is more effective in the repair avascular meniscal tear with stable meniscus-like tissue and to restore the native meniscus.

Aims We aimed to evaluate the long-term impact of fracture-related infection (FRI) on patients’ physical health and psychological wellbeing. For this purpose, quality of life after successful surgical treatment of FRIs of long bones was assessed. Methods A total of 37 patients treated between November 2009 and March 2019, with achieved eradication of infection and stable bone consolidation after long bone FRI, were included. Quality of life was evaluated with the EuroQol five-dimension questionnaire (EQ-5D) and German Short-Form 36 (SF-36) outcome instruments as well as with an International Classification of Diseases of the World Health Organization (ICD)-10 based symptom rating (ISR) and compared to normative data. Results With a mean follow-up of 4.19 years (SD 2.7) after the last surgery, the mean SF-36 score was 40.1 (SD 14.6) regarding the physical health component and 48.7 (SD 5.1) regarding the mental health component, compared to German normative values of 48.4 (SD 9.2) (p < 0.001) and 50.9 (SD 8.8) (p = 0.143). The mean EQ-5D index reached 0.76 (SD 0.27) with a mean EQ-5D visual analogue scale (VAS) rating of 65.7 (SD 22.7) compared to reference scores of 0.88 (p < 0.001) and 72.9 (p < 0.001). Mean scores of the ISR did not reveal significant psychological symptom burden, while an individual analysis showed moderate to severe impairments in 21.6% (n = 8) of the patients. Conclusion Even a mean 4.2 years (SD 2.7) after surgically successful treatment of FRI of long bones, patients report significantly lower quality of life in comparison to normative data. Future clinical studies on FRIs should focus on patient-related outcome measures enabling best possible shared treatment decision-making. Prevention methods and interdisciplinary approaches should be implemented to improve the overall quality of life of FRI patients. Cite this article: Bone Joint Res 2021;10(5):321–327.

Background: We aimed to evaluate the impact of knee periprosthetic joint infection (PJI) by assessing the patients’ long-term quality of life and explicitly their psychological wellbeing after successful treatment. Methods: Thirty-six patients with achieved eradication of infection after knee PJI were included. Quality of life was evaluated with the EQ-5D and SF-36 outcome instruments as well as with an ICD-10 based symptom rating (ISR) and compared to normative data. Results: At a follow-up of 4.9 ± 3.5 years the mean SF-36 score was 24.82 ± 10.0 regarding the physical health component and 46.16 ± 13.3 regarding the mental health component compared to German normative values of 48.36 ± 9.4 (p < 0.001) and 50.87 ± 8.8 (p = 0.003). The mean EQ-5D index reached 0.55 ± 0.33 with an EQ-5D VAS rating of 52.14 ± 19.9 compared to reference scores of 0.891 (p < 0.001) and 68.6 ± 1.1 (p < 0.001). Mean scores of the ISR revealed the psychological symptom burden on the depression scale. Conclusion: PJI patients still suffer from significantly lower quality of life compared to normative data, even years after surgically successful treatment. Future clinical studies should focus on patient-related outcome measures. Newly emerging treatment strategies, prevention methods, and interdisciplinary approaches should be implemented to improve the quality of life of PJI patients.

Aims This observational cross-sectional study aimed to answer the following questions: 1) how has nonunion incidence developed from 2009 to 2019 in a nationwide cohort; 2) what is the age and sex distribution of nonunions for distinct anatomical nonunion localizations; and 3) how high were the costs for surgical nonunion treatment in a level 1 trauma centre in Germany? Methods Data consisting of annual International Classification of Diseases (ICD)-10 diagnosis codes from German medical institutions from 2009 to 2019, provided by the Federal Statistical Office of Germany (Destatis), were analyzed. Nonunion incidence was calculated for anatomical localization, sex, and age groups. Incidence rate ratios (IRRs) were determined and compared with a two-sample z-test. Diagnosis-related group (DRG)-reimbursement and length of hospital stay were retrospectively retrieved for each anatomical localization, considering 210 patients. Results In 2019, a total of 11,840 nonunion cases (17.4/100,000 inhabitants) were treated. In comparison to 2018, the incidence of nonunion increased by 3% (IRR 1.03, 95% confidence interval (CI) 0.53 to 1.99, p = 0.935). The incidence was higher for male cases (IRR female/male: 0.79, 95% CI 0.76 to 0.82, p = 0.484). Most nonunions occurred at the pelvic and hip region (3.6/100,000 inhabitants, 95% CI 3.5 to 3.8), followed by the ankle and foot as well as the hand (2.9/100,000 inhabitants each). Mean estimated DRG reimbursement for in-hospital treatment of nonunions was highest for nonunions at the pelvic and hip region (€8,319 (SD 2,410), p < 0.001). Conclusion Despite attempts to improve fracture treatment in recent years, nonunions remain a problem for orthopaedic and trauma surgery, with a stable incidence throughout the last decade. Cite this article: Bone Joint Res 2022;11(8):541–547.

Zusammenfassung Hintergrund Die Behandlung periprothetischer Hüftinfektionen ist meist kostenintensiv und gilt im Allgemeinen als nicht kostendeckend für die Kliniken. Bei chronischen Infektionen ist oft ein zweizeitiger Prothesenwechsel indiziert, der als Fast-Track mit kurzem prothesenfreiem Intervall (2–4 Wochen) oder als Slow-Track mit langem prothesenfreiem Intervall (über 4 Wochen) erfolgen kann. Ziel Ziel dieser Arbeit war die Erfassung der Erlössituation beider Behandlungsformen im aktuellen aG-DRG-System 2020 unter Berücksichtigung erlösrelevanter Einflussfaktoren. Methoden Für Fast-Track und Slow-Track bei zweizeitigem septischem Hüftprothesenwechsel mit Nachweis eines Staphylococcus aureus (MSSA) wurden mittels einer Grouper-Software (3M KODIP Suite) anhand der Diagnosen (ICD-10-GM) und Prozeduren (OPS) Behandlungsfälle simuliert und in DRG eingruppiert. Erlösrelevante Parameter wie Verweildauer (VWD) und Nebendiagnosen (ND) wurden berücksichtigt. Zusätzlich wurden zwei reale Behandlungsfälle mit Fast-Track und Slow-Track miteinander verglichen. Ergebnisse Die Gesamterlöse betrugen beim Slow-Track bei einer VWD von 25 Tagen (ohne ND) 27.551 € und bei einer VWD von 42 Tagen (mit ND) 40.699 €. Beim Fast-Track hingegen lag der Gesamterlös bei 23.965 € bei einer VWD von 25 Tagen (ohne ND) und bei 27.283 € bei einer VWD von 42 Tagen (mit ND). Bei den realen Behandlungsfällen zeigte sich ebenfalls eine deutliche Differenz des Gesamterlöses von 12.244 € zugunsten des Slow-Tracks. Diskussion Auch im aG-DRG-System 2020 scheint der zweizeitige Hüftprothesenwechsel mit langem Interimsintervall insbesondere bei multimorbiden Patienten aus Krankenhaussicht ökonomisch vorteilhafter zu sein als das Fast-Track-Konzept, wodurch ein finanzielles Hemmnis zur Behandlung solcher Patienten mit kurzem Interimsintervall geschaffen wird.