Abstract Background Due to the difference in size between the humeral head and the glenoid, the shoulder joint is prone to instability. Therefore, the reconstruction of the physiological joint morphology is of great importance in shoulder joint preservation and replacement surgery. The aim of this study was to describe physiological reference parameters for the morphology of the glenoid for the first time. Material and methods MRI images of the shoulder joints of 418 patients (mean age: 50.6 years [± 16.3]) were retrospectively analysed in a low-grade osteoarthritic population. The glenoid distance in coronal (GDc) and axial view (GDa), glenoid inclination (GI) and version (GV) as well as scapula neck length (SNL) were measured. Parameters were studied in association for age, gender, side and degeneration grade. Results Mean GDc was 33.4 mm (± 3.6), mean GDa 26.8 mm (± 3.2), mean GI 10.5° (± 6.4), mean GV -0.4 mm (± 5.4) and mean SNL was 33.4 mm (± 4.7). GDa was significant higher in right shoulders (p < 0.001). GDc and GDa showed significant higher mean values in older patients (p < 0.001) and in shoulders with more severe degenerative changes (p < 0.05). While GDc, GDa and SNL were significant larger in male patients (p < 0.001), GI had a higher mean value in female shoulders (p = 0.021). Conclusion Age, gender and shoulder joint degeneration influence changes in the morphological parameters of the glenoid. These findings have to be considered in shoulder diagnostics and surgery. Clinical trial number Not applicable.

The aim of the present study was to determine physiological reference values for the morphology of the patella and to analyse these parameters according to patella position in healthy knee joints. Healthy knee joints of 409 patients (mean age, 52.3 years [± 16.8]) were analysed retrospectively on MRI images for Insall-Salvati index (ISI), sagittal patella thickness (PTS) and patella length (PLS) as well as axial patella thickness (PTA) and patella width (PWA). Differences between patellar diameters were analysed depending on ISI, side, age and gender. Mean PTS was 20.1 mm (± 2.4), PLS 44.0 mm (± 4.4), PTA 21.8 mm (± 2.4) and PWA 44.5 mm (± 4.7). Depending on the vertical patellar position (ISI), all patellar parameters (p < 0.01) showed significant differences between patients with a patella alta, norma and baja. In general, a smaller ISI showed higher measured values for the patellar parameters. There were no significant differences for the laterality. Only PTS showed a significant age difference (p = 0.031). All parameters were significantly larger in male compared to female knees (p < 0.001). Reference parameters for the patella morphology are reported. Concluding from the results, a relationship between vertical patellar position and patellar morphology seems to exist. This finding should be taken into account in diagnostics and therapy of patella disorders.

ObjectiveClosed reduction and dynamic hip screw (DHS) osteosynthesis are preferred as joint‐preserving therapy in case of medial femoral neck fractures (MFNFs). A change in the femoral offset (CFO) can cause gait abnormality, impingement, or greater trochanteric pain syndrome. It is unknown whether the femoral offset (FO) can be postoperatively fully restored. The aim of the study was to investigate the extent of a possible CFO in hip joints after DHS osteosynthesis in the case of an MFNF.MethodsIn this retrospective study, 104 patients (mean age: 71.02 years, men: n = 50, women: n = 54) with MFNF who underwent closed reduction and DHS osteosynthesis were analyzed by postoperative x‐rays to assess CFO between the operated (OS) and nonoperated joint side (NOS). The studies covered the time period 2010–2020. A statistical comparison was performed between the mean values of FO between OS and NOS, taking into account patient age, gender, and fracture severity.ResultsAll operated hip joints showed a CFO. In 76.0% (79 of 104), the FO decreased (FOD), and in 24.0% (25 of 104), the FO increased (FOI). A critical CFO (>15% CFO) was detected in 52.9% (55 of 104). In hip joints with postoperative FOD, the mean FO between NOS (49.15 mm [±6.56]) and OS (39.32 mm [±7.87]) and in hip joints with postoperative FOI the mean FO between NOS (41.59 [±8.21]) and OS (47.27 [±6.68]) differed significantly (p < 0.001). Preoperative FO (r S: −0.41; p > 0.001) and caput–collum–diaphyseal angle (CCD; r S: 0.34; p > 0.001) correlated with postoperative CFO. FOD was found in hip joints with a preoperative FO >44 mm and CCD <134° vice versa FOI in hip joints with a preoperative FO <44 mm and CCD >134°.ConclusionClosed reduction and DHS osteosynthesis in patients with MFNF result in a clustered significant CFO. The individual FO should be taken into account pre‐ and intraoperatively to avoid a postoperative extensive CFO.

Background: In the age of individualised arthroplasty, the question arises whether currently available standard implants adequately consider femoral condylar morphology (FCM). Therefore, physiological reference values of FCM are needed. The aim was to establish physiological reference values for anterior (ACO) and posterior condylar offset (PCO) as well as for the length of the medial (LMC) and lateral femoral condyles (LLC). Methods: The knee joints of 517 patients (mean age: 52.3 years (±16.8)) were analysed retrospectively using MRI images. Medial (med) and lateral (lat) ACO and PCO, as well as LMC and LLC, were measured. All FCM parameters were examined for association with age, gender, side and osteoarthritis. Results: Mean ACOmed was 2.8 mm (±2.5), mean ACOlat was 6.7 mm (±2.3), mean PCOmed was 25.7 mm (±4.6), mean PCOlat was 23.6 mm (±3.0), mean LMC was 63.7 mm (±5.0) and mean LLC was 64.4 mm (±5.0). Except for PCOmed, the mean values of all other FCM parameters were significantly higher in male knees compared to female knees. ACOmed and PCOmed showed significant side-specific differences. There were no significant differences in relation to age and osteoarthritis. Conclusion: The study showed significant differences in FCM side- and gender-specifically in adult knees. These aspects should be considered in the discussion of individual and gender-specific knee joint replacement.

Background: Pelvis fractures are commonly stabilized by surgical implants to facilitate their healing. However, such implants immobilize the iliosacral joint for up to a year until removal. We report how iliosacral joint immobilization affects the walking of patients. Methods: The gaits of patients with immobilized sacroiliac joints after unstable pelvic fracture (n = 8; mean age: 45.63 ± 23.19; five females and three males) and sex- and age-matched healthy control individuals (n = 8; mean age: 46.50 ± 22.91; five females and three males) were recorded and analyzed using a motion capture system. The forces between the tread and feet were also recorded. Standard gait parameters as well as dynamic patterns of joint angles and moments of the lower extremities were analyzed using the simulation software OpenSim. Results: With the exception of hip extensor strength, the monitored joint parameters of the patients showed task-dependent deviations during walking, i.e., plantarflexor force was increased when stepping on an elevated surface, as were hip flexion and extensor moments, knee flexion and extensor moments, as well as ankle dorsiflexion and the associated negative plantarflexor force during stance on the elevated surface. Conclusions: Iliosacral joint fixation causes reduced forward and upward propulsion and requires an extended range of hip motion in the sagittal plane. Patients show significant mobility limitation after iliosacral screw fixation.

Background: The tibial slope (TS) defines the posterior inclination of the tibial plateau (TP). The “individual physiological” TS plays a crucial role in knee-joint stability and should be taken into account in knee-joint surgery. The aim of this study was to analyse the specific morphology of the TS for the medial (med) and lateral (lat) TP in relation to patient characteristics and the measurement method. Methods: In this retrospective study, MRI images of knee joints from 720 patients (mean age: 49.9 years [±17.14]) were analysed. The TS was assessed using two established methods according to Hudek (TSH) and Karimi (TSK) for the med and lat TP and gender/side specificity was analysed. Results: TSH for the med and lat TP showed significantly (p < 0.001) different values compared to TSK (TSKmed: 2.6° (±3.7), TSHmed: 4.8° (±3.5); TSKlat: 3.0° (±4.0), TSHlat: 5.2° (±3.9)). The angles of the lat TP were significantly higher than those of the med TP (TSK: p < 0.001; TSH: p = 0.002). Females showed a higher med and lat TS compared to males (p < 0.001). Conclusions: The measurement method has an influence on the values of the TS in knee-joint MRIs. The TS is significantly different for the med and lat TP regardless of the measurement method. There are gender-specific differences for the TS.

Background: Physiological reference values for morphological parameters of the hip (MPH) are of clinical importance for the treatment of painful, degenerated or fractured hip joints, as well as to detect morphological deformities, which could result in early osteoarthritis of the hip. Currently, sufficient data for MPH are lacking. Therefore, it remains unclear if age-dependent alterations in adult hip morphology are physiological and if there are side- and gender-dependent differences. The aim of the study was to analyze MPH according to gender, side and age in a large-scaled cohort by CT scans. Methods: A total of 1576 hip joints from 788 patients (female: 257, male: 531; mean age: 58.3 years (±18.9; 18–92 years)) were analyzed by CT. For all hips, acetabular anteversion (AcetAV); lateral centrum edge angle (LCE); acetabular index (AI); femoral neck version (FNV); centrum-collum-diaphyseal angle (CCD); and anterior alpha angle (AαA) were measured. Results: The mean values in this cohort were: AcetAV 20.5° (±6.9); LCE 40.8° (±8.8); AI 0.3° (±5.3); FNV 11.0° (±9.8); CCD 129.9° (±7.4); and AαA 41.2° (±7.7). There was a detectable side-specific difference for AcetAV (p = 0.001); LCE (p < 0.001); CCD (p < 0.001); and AαA (p < 0.001). All the analyzed parameters showed a significant gender-specific difference, except for AI (p = 0.37). There was a significant correlation between age and AcetAV (r = 0.17; p < 0.001); LCE (r = 0.39; p < 0.001); AI (r = −0.25; p < 0.001); CCD (r = −0.15; p < 0.001); and AαA (r = 0.09; p < 0.001), except FNV (p = 0.79). Conclusions: There are side-, gender- and age-specific alterations in hip morphology, which have to be considered in treating hip joint pathologies.

Time is of the essence in the management of severely injured patients. This is especially true in patients with mediastinal vascular injury (MVI). This rare, yet life threatening injury needs early detection and immediate decision making. According to the ATLS guidelines [American College of Surgeon Committee on Trauma in Advanced Trauma Life Support (ATLS®), 10th edn, 2018], chest radiography (CXR) is one of the first-line imaging examinations in the Trauma Resuscitation Unit (TRU), especially in patients with MVI. Yet thorough interpretation and the competence of identifying pathological findings are essential for accurate diagnosis and drawing appropriate conclusion for further management. The present study evaluates the role of CXR in detecting MVI in the early management of severely injured patients. We addressed the question in two ways. (1) We performed a retrospective, observational, single-center study and included all primary blunt trauma patients over a period of 2 years that had been admitted to the TRU of a Level-I Trauma Center. Mediastinal/chest (M/C) ratio measurements were calculated from CXRs at three different levels of the mediastinum to identify MVI. Two groups were built: with MVI (VThx) and without MVI (control). The accuracy of the CXR findings were compared with the results of whole-body computed tomography scans (WBCT). (2) We performed another retrospective study and evaluated the usage of sonography, CXR and WBCT over 15 years (2005–2019) in level-I–III Trauma Centers in Germany as documented in the TraumaRegister DGU® (TR-DGU). Study I showed that in 2 years 267 patients suffered from a significant blunt thoracic trauma (AIS ≥ 3) and met the inclusion criteria. 27 (10%) of them suffered MVI (VThx). Through the initial CXR in a supine position, MVI was detected in 56–92.6% at aortic arch level and in 44.4–100% at valve level, depending on different M/C-ratios (2.0–3.0). The specificity at different thresholds of M/C ratio was 63.3–2.9% at aortic arch level and 52.9–0.4% at valve level. The ROC curve showed a statistically random process. No significant differences of the cardiac silhouette were observed between VThx and Control (mean cardiac width was 136.5 mm, p = 0.44). Study II included 251,095 patients from the TR-DGU. A continuous reduction of the usage of CXR in the TRU could be observed from 75% in 2005 to 25% in 2019. WBCT usage increased from 35% in 2005 to 80% in 2019. This development was observed in all trauma centers independently from their designated level of care. According to the TRU management guidelines (American College of Surgeon Committee on Trauma in Advanced Trauma Life Support (ATLS®), 10th edn, 2018; Reissig and Kroegel in Eur J Radiol 53:463–470, 2005) CXR in supine position is performed to detect pneumothorax, hemothorax and MVI. Our study showed that sensitivity and specificity of CXR in detecting MVI was statistically and clinically not reliable. Previous studies have already shown that CXR is inferior to sonography in detecting pneumothorax and hemothorax. Therefore, we challenge the guidelines and suggest that the use of CXR in the early management of severely injured patients should be individualized. If sonography and WBCT are available and reasonable, CXR is unnecessary and time consuming. The clinical reality reflected in the usage of CXR and WBCT over time, as documented in the TR-DGU, seems to support our statement.

Percutaneous screw fixation combined with pelvic reduction is a surgical technique used to stabilize fractures of the posterior pelvic ring. This is the standard surgical treatment of unstable posterior pelvic ring injuries. The primary goal of this treatment is an anatomic reduction and stable fixation. This has been shown to reduce pain and improve the patients' long‐term well‐being. The aim of this analysis was to determine the possible screw lengths and the positioning of the screws in the S1 and S2 sacral segments. A population of 697 pelvises from the Stryker Orthopaedic Modeling and Analytics database were analyzed. The dimensions of the S1 and S2 screw corridors were determined and after assessing for sacral dysmorphism, the correct screw placement was chosen to determine the necessary screw length for surgical treatment. The measurements of the screw lengths show a Gaussian distribution for the analyzed population. The percentage of dysmorphic pelvises for the S1 screw corridor was 31.3% and for the S2 corridor 8%. Average screw length for S1 was 163.8 ± 16.2 mm and for the S2 137.3 ± 9.5 mm. The results show that the S1/S2 axis cannot be used for a trans‐sacral screw placement in every patient. The study shows that intraosseous screw corridors are present in 68.7% of the patients in the S1 position and in 92% at the S2 level where an intended implant can be placed fully intraosseous.

Abstract Introduction: The plain film chest x-ray in supine position (CXR) during the initial management of severely injured patients has almost lost its clinical relevance, since it has been challenged by extended focused assessment with sonography in trauma (eFAST) in early trauma management, due to its superiority in detecting a pneumo-/hematothorax. One of the last diagnostic fields in such setting of CXR is the mediastinal vascular injury. These injuries are rare yet life-threatening events. The most easily accessible diagnostic tool to identify these patients would be CXR as it is still one of the standard diagnostic tools in the early assessment of severely injured patients with significant thoracic trauma (Abbreviated Injury Scale, AIS ≥3). This study evaluates the role of early CXR in the Trauma Resuscitation Unit (TRU) in the last diagnostic field where eFAST cannot provide an answer: detecting mediastinal vascular injury in severely injured patients.Method: This retrospective, observational, single-centre study included all primary blunt trauma patients of a 24 months time period, that had been admitted to the TRU. Mediastinal/chest (M/C) ratio measurements were taken from CXRs at three defined levels of the mediastinum. The accuracy of the CXR findings were compared to whole-body computed tomography scans (WBCT) and therapeutic consequences were observed. Additionally a 15 years (2005–2019) time period out of the TraumaRegister DGU® was evaluated regarding usage of eFAST, CXR und WBCT in Level-1, -2, and − 3 Trauma Centres in Germany.Results: A total of 267 patients showed a significant blunt thoracic trauma (27 with mediastinal vascular injury (VThx)). The initial CXR in a supine position was unreliable for detecting mediastinal vascular injury. The sensitivity and specificity at different thresholds of maximum M/C ratio (2.0–3.0) were not clinically acceptable. The aortic contour and haemato- and pneumothorax were not reliably detected in the initial CXRs. No significant differences in the cardiac silhouette were observed between patients with or without mediastinal vascular injury (mean cardiac width, 136.5 mm, p = 0.44). No therapeutic consequences were drawn after CXR in the study period. The data from the TR-DGU (N = 251,095) showed a continuous reduction of CXR from 75% (2005) to 25% (2019), while WBCT raised from 35% to a steady level of about 80%. This development was seen in all trauma hospitals almost simultaneously.Conclusion: In present guidelines, CXR remains an integral diagnostic element during early TRU management, although several prior publications show the superior role of eFAST. Our data support that in most cases, CXR is time consuming and provides no benefit during initial management of severely injured patients and might delay the use of WBCT. The trauma centres in Germany have already significantly reduced the usage of CXR in the TRU. We therefore recommend to revise current guidelines and emphasise eFAST and rapid diagnostic through WBCT if rapidly available.

A correction to this paper has been published: https://doi.org/10.1007/s00068-021-01698-w

Background Fragility fractures without significant trauma of the pelvic ring in older patients were often treated conservatively. An alternative treatment is surgery involving percutaneous screw fixation to stabilize the posterior pelvic ring. This surgical treatment enables patients to be mobilized quickly and complications associated with bedrest and temporary immobility are reduced. However, the functional outcome following surgery and quality of life of the patients have not yet been investigated. Here, we present a comprehensive study addressing the long-term well-being and the quality of life of patients with fragility pelvic ring fractures after surgical treatment. Methods Between 2011–2019, 215 geriatric patients with pelvic ring fractures were surgically treated at the university hospital in Göttingen (Germany). Of these, 94 patients had fragility fractures for which complete sets of computer tomography (CT) and radiological images were available. Fractures were classified according to Tile and according to the FFP classification of Rommens and Hofmann. The functional outcome of surgical treatment was evaluated using the Majeed pelvic score and the Short Form Health Survey-36 (SF-36). Results Thirty five tile type C and 48 type B classified patients were included in the study. After surgery eighty-three patients scored in average 85.92 points (± 23.39) of a maximum of 100 points using the Majeed score questionnaire and a mean of 1.60 points on the numerical rating scale ranging between 0 and 10 points where 0 points refers to “no pain” and 10 means “strongest pain”. Also, the SF-36 survey shows that surgical treatment positively effects patients with respect to their general health status and by restoring vitality, reducing bodily pain and an increase of their general mental health. Conclusions Patients who received a percutaneous screw fixation of fragility fractures of the posterior pelvic ring reported an overall positive outcome concerning their long-term well-being. In particular, older patients appear to benefit from surgical treatment. Trial registration Functional outcome and quality of life after surgical treatment of fragility fractures of the posterior pelvic ring, DRKS00024768. Registered 8th March 2021 - Retrospectively registered. Trial registration number DRKS00024768 .

BACKGROUND:The cestode Echinococcus granulosus causes hydatid disease. In addition to manifestations in the liver and lung, it can lead to cystic lesions in the spine.CASE DESCRIPTION:We report a 42-year-old male patient with primary hydatid disease in the eighth thoracic vertebra. The only clinical symptom was chronic back pain. Although laboratory findings were normal, imaging displayed lytic destruction that raised the suspicion of a metastatic disease. Diagnostics of the thoraces and abdomen did not reveal other pathologic abnormalities. Follow-up magnetic resonance imaging (MRI) depicted a progressive compression of the spinal cord and inhomogeneous structure in the fat-suppressed sequences. Because the Jamshidi biopsy was inconclusive, the tumor board recommended surgery. Dorsal decompression, spondylodesis of T6-T10, and vertebral column resection of T8 with complete cyst removal were performed. The resected vertebrae showed a mucous-like lesion with white granular tissue interfusing the whole vertebral body. A pathologic examination and enzyme-linked immunosorbent assay confirmed E. granulosus. Thus chemotherapy with albendazole was initiated. A follow-up MRI of the whole spine confirmed complete remission and found no additional resettlements. The patient's back pain was resolved without neurologic deficits.CONCLUSIONS:For lytic manifestations of the vertebral column, hydatid cysts should be considered a differential diagnosis in addition to malignant metastasis, tuberculosis, and osteomyelitis. Thorough surgical resection and strict follow-up are necessary.