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Background: If an increased posterior tibial slope (PTS) and concomitant unicompartmental osteoarthritis are present, a simultaneous sagittal (slope) and coronal correcting high tibial osteotomy has been recommended. However, no study has investigated the accuracy of such combined high tibial slope correction osteotomies., Purpose: (1) To report the accuracy of navigated high tibial slope correction osteotomies using patient-specific instruments (PSI) and (2) to analyze the influence of an open wedge osteotomy (OWO) versus a closed wedge osteotomy (CWO) and the hinge axis angle (HAA) on the accuracy of the PTS correction., Study Design: Cohort study; Level of evidence, 3., Methods: All PSI PTS-reducing osteotomies performed at 1 institution between 2019 and 2022 were reviewed. Three-dimensional (3D) accuracy was defined as the mean absolute 3D angular difference between the planned and achieved surgical correction (in degrees) in 3D models of computed tomography data. The influence of OWO versus CWO and the HAA on the reported accuracy was analyzed and a cutoff defined using receiver operating characteristic curve analysis., Results: Eighteen patients who underwent a slope-reducing CWO (n = 9) or OWO (n = 9) were included. The 3D accuracy for PTS was 2.3°± 1.1° (mean ± SD), with CWO being more accurate than OWO (1.4°± 0.9° vs 3.1°± 0.6°; P < .01). Accuracy strongly correlated with the HAA ( r = 0.788; P < .01). An HAA >38.9° predicted a PTS error >2° (odds ratio, 1.12 [95% CI, 1.04-1.20; P = .004]; area under the curve, 0.95 [95% CI, 0.89-1.00; P < .001]) corresponding to a coronal/sagittal correction of 0.8:1., Conclusion: Slope-reducing osteotomy can accurately be achieved using PSI. CWO demonstrated an increased accuracy when compared with OWO, which strongly depended on the HAA. With an aim of combined PTS and coronal correction, CWO should be considered the primary choice for accurate slope reduction with a coronal/sagittal correction cutoff of 0.8:1 (HAA, 38.9°)., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Lower extremity trauma can have a significant impact on a patient's quality of life. The LIMB-Q is a recently developed and validated patient-reported outcome measure that assesses patient-specific outcomes and experience of health care. The aim of this study was to translate and linguistically validate the LIMB-Q from English to German., Methods: The translation was performed by combining World Health Organization and Professional Society for Health Economics and Outcomes Research guidelines. The process consisted of forward translations, a backward translation, expert panel meetings, cognitive debriefing interviews with patients, and several rounds of discussion and reconciliation with the creators of LIMB-Q. The goal was to obtain a culturally and conceptually accurate translation of LIMB-Q into German for use in Switzerland., Results: From the two forward translations, there was one primary discrepancy between the two translators that was discussed to determine the most conceptually accurate translation. From the backward translations, there were 63 items that required discussion and re-translation. Nine patients participated in the cognitive debriefing interviews, which led to three items being modified. The translation process led to a linguistically validated and conceptually equivalent German version of the LIMB-Q., Conclusions: The German (Switzerland) version of LIMB-Q is now available. This will offer a valuable tool for lower extremity trauma research and clinical care in German-speaking populations., Competing Interests: Drs. Klassen and Mundy are co-developers of the LIMB-Q and could potentially receive a share of any license revenue on the inventor sharing policies from the institutions that own the LIMB-Q. Nicole Lindenblatt acts as consultant and scientific advisor for Medical Microinstruments. All the other authors have no financial interest to declare in relation to the content of this article., (Copyright © 2024 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons.)

Background: Acquired adult flatfoot deformity (AAFD) results in a loss of the medial longitudinal arch of the foot and dysfunction of the posteromedial soft tissues. Hintermann osteotomy (H-O) is often used to treat stage II AAFD. The procedure is challenging because of variations in the subtalar facets and limited intraoperative visibility. We aimed to assess the impact of augmented reality (AR) guidance on surgical accuracy and the facet violation rate., Methods: Sixty AR-guided and 60 conventional osteotomies were performed on foot bone models. For AR osteotomies, the ideal osteotomy plane was uploaded to a Microsoft HoloLens 1 headset and carried out in strict accordance with the superimposed holographic plane. The conventional osteotomies were performed relying solely on the anatomy of the calcaneal lateral column. The rate and severity of facet joint violation was measured, as well as accuracy of entry and exit points. The results were compared across AR-guided and conventional osteotomies, and between experienced and inexperienced surgeons., Results: Experienced surgeons showed significantly greater accuracy for the osteotomy entry point using AR, with the mean deviation of 1.6 ± 0.9 mm (95% CI 1.26, 1.93) compared to 2.3 ± 1.3 mm (95% CI 1.87, 2.79) in the conventional method ( P  = .035). The inexperienced had improved accuracy, although not statistically significant ( P  = .064), with the mean deviation of 2.0 ± 1.5 mm (95% CI 1.47, 2.55) using AR compared with 2.7 ± 1.6 mm (95% CI 2.18, 3.32) in the conventional method. AR helped the experienced surgeons avoid full violation of the posterior facet ( P  = .011). Inexperienced surgeons had a higher rate of middle and posterior facet injury with both methods ( P  = .005 and .021)., Conclusion: Application of AR guidance during H-O was associated with improved accuracy for experienced surgeons, demonstrated by a better accuracy of the osteotomy entry point. More crucially, AR guidance prevented full violation of the posterior facet in the experienced group. Further research is needed to address limitations and test this technology on cadaver feet. Ultimately, the use of AR in surgery has the potential to improve patient and surgeon safety while minimizing radiation exposure., Clinical Relevance: Subtalar facet injury during lateral column lengthening osteotomy represents a real problem in clinical orthopaedic practice. Because of limited intraoperative visibility and variable anatomy, it is hard to resolve this issue with conventional means. This study suggests the potential of augmented reality to improve the osteotomy accuracy., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Disclosure forms for all authors are available online.

Purpose: The multifactorial nature of patellofemoral instability requires a comprehensive assessment of the affected patients. While an association between tibial tuberosity (TT) torsion and patellofemoral instability is known, its specific effect has not yet been investigated. This study investigated the effect of TT torsion on patellofemoral instability., Methods: This retrospective cohort study compared patients who underwent surgical intervention for patellofemoral instability and asymptomatic controls. TT torsion was measured in addition to other commonly assessed risk factors for patellofemoral instability using standardised computed tomography (CT) data of the lower extremities. The diagnostic performances of the assessed parameters were evaluated using receiver operating characteristic curve analysis and odds ratios (ORs) were calculated., Results: The patellofemoral instability group consisted of 79 knees, compared to 72 knees in the asymptomatic control group. Both groups differed significantly in all assessed parameters (p < 0.001), except for tibial torsion (n.s.). Among all parameters, TT torsion presented the best diagnostic performance for predicting patellar instability with an area under the curve of 0.95 (95% confidence interval [CI], 0.91-0.98; p < 0.001). A cut-off value of 17.7° yielded a 0.87 sensitivity and 0.89 specificity to predict patellar instability (OR, 55.2; 95% CI, 20.5-148.6; p < 0.001)., Conclusion: Among the evaluated risk factors, TT torsion had the highest predictive value for patellofemoral instability. Patients with TT torsions ≥ 17.7° showed a 55-fold increased probability of patellofemoral instability. Therefore, TT torsion should be included in the assessment of patients with patellofemoral instability., Level of Evidence: Level III., (© 2024 The Authors. Knee Surgery, Sports Traumatology, Arthroscopy published by John Wiley & Sons Ltd on behalf of European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)

Background: Painful degenerative joint disease (DJD) of the first metatarsophalangeal joint (MTP I), or hallux rigidus, mainly occurs in later stages of life. For end-stage hallux rigidus, MTP I arthrodesis is considered the gold standard. As young and active patients are affected considerably less frequently, it currently remains unclear, whether they benefit to the same extent. We hypothesized that MTP I arthrodesis in younger patients would lead to an inferior outcome with decreased rates of overall with lower rates of patient postoperative pain and function compared to an older cohort., Methods: All patients aged <50 years who underwent MTP I arthrodesis at our institution between 1995 and 2012 were included in this study. This group was then matched and compared with a group of patients aged >60 years. Minimum follow-up was 10 years. Outcome measures were Tegner activity score (TAS), a "Virtual Tegner activity score" (VTAS), the visual analog scale (VAS), and the Foot Function index (FFI)., Results: Sixty-one MTP I fusions (n = 28 young, n = 33 old) in 46 patients were included in our study at an average of 14 years after surgery. Younger patients experienced significantly more pain relief as reflected by changes in VAS and FFI Pain subscale scores. No difference in functional outcomes was found with change in the FFI function subscale or in the ability to have desired functional outcomes using the ratio of TAS to VTAS. Revision rate did not differ between the two groups apart from hardware removal, which was significantly more likely in the younger group., Conclusion: In patients below the age of 50 years with end-stage DJD of the first metatarsal joint, MTP I arthrodesis not only yielded highly satisfactory postoperative results at least equal outcome compared to an older cohort of patients aged >60 years at an average 14 years' follow-up. Based on these findings, we consider first metatarsal joint fusion even for young patients is a valid option to treat end-stage hallux rigidus., Level of Evidence: Level III, a case-control study., Competing Interests: Ethical ApprovalEthical approval for this study was obtained from the local research ethics committee of Zurich (KEK-ZH-Nr. 2019-01985). Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. ICMJE forms for all authors are available online.

Purpose: The goal of this study is (1) to assess differences between two-dimensional (2D) weight-bearing (WB) and three-dimensional (3D) nonweight-bearing (NWB) planning in total knee arthroplasty (TKA) and (2) to identify factors that influence intermodal differences., Methods: Retrospective single-centre analysis of patients planned for a TKA with patient-specific instruments (PSI). Preoperative WB long-leg radiographs and NWB computed tomography were analysed and following radiographic parameters included: hip-knee-ankle angle (HKA) (+varus/-valgus), joint line convergence angle (JLCA), femorotibial subluxation and bony defect classified according to Anderson. Preoperative range of motion was also considered as possible covariate. Demographic factors included age, sex, and body mass index., Results: A total of 352 knees of 323 patients (66% females) with a mean age of 66 ± 9.7 years were analysed. The HKA differed significantly between 2D and 3D planning modalities; varus knees ( n  = 231): 9.9° ± 5.1° vs. 6.7° ± 4°, p  < 0.001; valgus knees ( n  = 121): -8.2° ± 6° vs. -5.5° ± 4.4°, p  < 0.001. In varus knees, HKA ( β  = 0.38; p  < 0.0001) and JLCA ( β  = 0.14; p  = 0.03) were associated with increasing difference between 2D/3D HKA. For valgus knees, HKA ( β  = -0.6; p  < 0.0001), JLCA ( β  = -0.3; p  = 0.0001) and lateral distal femoral angle ( β  = -0.28; p  = 0.03) showed a significant influence on the mean absolute difference., Conclusion: The coronal alignment in preoperative 3D model for PSI-TKA significantly differed from 2D WB state and the difference between modalities correlated with the extent of varus/valgus deformity. In the vast majority of cases, the 3D NWB approach significantly underestimated the preoperative deformity, which needs to be considered to achieve the planned correction when using PSI in TKA., Level of Evidence: Level III., Competing Interests: Sandro F. Fucentese is a consultant for Medacta SA (Switzerland), Smith & Nephew (United Kingdom), Zimmer Biomet and Karl Storz SE & Co. KG (Germany). The other authors have no conflict of interest to declare., (© 2024 The Author(s). Journal of Experimental Orthopaedics published by John Wiley & Sons Ltd on behalf of European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)

Purpose: Recent data suggest that individual morphologic factors should be respected to restore preoperative patellofemoral alignment and thus reduce the likelihood of anterior knee pain. The goal of this study was to investigate the effect of excessive femoral torsion (FT) on clinical outcome of TKA., Methods: Patients who underwent TKA and complete preoperative radiographic evaluation including a long-leg radiograph and CT scan were included. 51 patients showed increased FT of > 20° and were matched for age/sex to 51 controls (FT < 20°). Thirteen patients were lost to follow-up. Thirty-eight matched pairs were compared after a 2 year follow-up clinically (Kujala and patellofemoral score for TKA) and radiographically (FT, frontal leg axis, TT-TG, patellar thickness, patellar tilt, and lateral displacement of patella). Functional alignment of TKA was performed (hybrid-technique). All patellae were denervated but no patella was resurfaced., Results: There was no significant difference between clinical scores two years after surgery between patients with normal and excessive FT (n.s.). Kujala score was 64.3 ± 16.7 versus 64.8 ± 14.4 (n.s.), and patellofemoral score for TKA was 74.3 ± 21 versus 78.5 ± 20.7 (n.s.) for increased FT group and control group, respectively. There was no correlation between preoperative FT and clinical scores. Other radiographic parameters were similar between both groups. No correlations between clinical outcomes and preoperative/postoperative frontal leg axis or total leg axis correction were found (n.s.)., Conclusion: If the leg axis deformity is corrected to a roughly neutral alignment during cemented TKA, including patellar denervation, then excessive FT was not associated with patellofemoral pain or instability., Level of Evidence: Prospective comparative study, level II., (© 2022. The Author(s).)

Background: Bone tunnel enlargement after single-bundle anterior cruciate ligament reconstruction remains an unsolved problem that complicates revision surgery., Hypothesis: Positioning of an osteoconductive scaffold at the femoral tunnel aperture improves graft-to-bone incorporation and thereby decreases bone tunnel widening., Study Design: Randomized controlled trial; Level of evidence, 1., Methods: In a 1:1 ratio, 56 patients undergoing primary anterior cruciate ligament reconstruction were randomized to receive femoral fixation with cortical suspension fixation and secondary press-fit fixation at the tunnel aperture of the tendon graft only (control) or with augmentation by an osteoconductive scaffold (intervention). Adverse events, patient-reported outcomes, and passive knee stability were recorded over 2 years after the index surgery. Three-dimensional bone tunnel widening was assessed using computed tomography at the time of surgery and 4.5 months and 1 year postoperatively., Results: The intervention group exhibited a similar number of adverse events as the control group (8 vs 10; P = .775) including 2 partial reruptures in both groups. The approach was feasible, although 1 case was encountered where the osteoconductive scaffold was malpositioned without adversely affecting the patient's recovery. There was no difference between the intervention and control groups in femoral bone tunnel enlargement, as expressed by the relative change in tunnel volume from surgery to 4.5 months (mean ± SD, 36% ± 25% vs 40% ± 25%; P = .644) and 1 year (19% ± 20% vs 17% ± 25%; P =.698)., Conclusion: Press-fit graft fixation with an osteoconductive scaffold positioned at the femoral tunnel aperture is safe but does not decrease femoral bone tunnel enlargement at postoperative 1 year., Registration: NCT03462823 (ClinicalTrials.gov identifier)., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: Funding was provided by the Swiss Innovation Agency (grant 25382.2 PFLS-LS-1). T.G., E.B., X.L., and J.G.S. are coinventors of a patent on the tested device (BTB-Converter), filed by ZuriMED Technologies; E.B. and X.L. are employed by ZuriMED Technologies; and E.B., X.L., and J.G.S. are shareholders in ZuriMED Technologies. S.F.F. has received consulting fees from Medacta, Zimmer Biomet, Smith & Nephew, and Storz. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2023.)

Purpose: Intraoperative hinge fractures in distal femur osteotomies represent a risk factor for loss of alignment and non-union. Using finite element analysis, the goal of this study was to investigate the influence of different hinge widths and osteotomy corrections on hinge fractures in medial closed-wedge and lateral open-wedge distal femur osteotomies., Methods: The hinge was located at the proximal margin of adductor tubercle for biplanar lateral open-wedge and at the upper border of the lateral femoral condyle for biplanar medial closed-wedge distal femur osteotomies, corresponding to optimal hinge positions described in literature. Different hinge widths (5, 7.5, 10 mm) were created and the osteotomy correction was opened/closed by 5, 7.5 and 10 mm. Tensile and compressive strain of the hinge was determined in a finite element analysis and compared to the ultimate strain of cortical bone to assess the hinge fracture risk., Results: Doubling the correction from 5 to 10 mm increased mean tensile and compressive strain by 50% for lateral open-wedge and 48% for medial closed-wedge osteotomies. A hinge width of 10 mm versus 5 mm showed increased strain in the hinge region of 61% for lateral open-wedge and 32% for medial closed-wedge osteotomies. Medial closed-wedge recorded a higher fracture risk compared to lateral open-wedge osteotomies due to a larger hinge cross-section area (60-67%) for all tested configurations. In case of a 5 mm hinge, medial closed-wedge recorded 71% higher strain in the hinge region compared to lateral open-wedge osteotomies., Conclusion: Due to morphological features of the medial femoral condyle, finite element analysis suggests that lateral-open wedge osteotomies are the preferable option if larger corrections are intended, as a thicker hinge can remain without an increased hinge fracture risk., (© 2023. The Author(s).)

Purpose: Anterior knee pain (AKP) is common following total knee arthroplasty. The tibial tuberosity trochlear groove distance (TTTG) influences patellofemoral joint loading in the native knee. Increased TTTG may lead to maltracking of the patella and anterior knee pain. The purpose of this study was to investigate potential changes in TTTG following total knee arthroplasty (TKA)., Methods: TTTG was measured on preoperative CT data on a consecutive series of patients scheduled to receive TKA with patient-specific instrumentation, and compared to a computer simulation of the postoperative TTTG. Preoperative TTTG was measured with a 3D planning software in 250 knees. The postoperative result was simulated and TTTG measured within the software. Three different groups were analysed: neutral (180° ± 3) (n = 50), valgus (> 190°) (n = 100), and varus (< 170°) (n = 100)., Results: Median preoperative to simulated postoperative TTTG decreased from 15.0 [interquartile range (IQR) 6.0] mm to 6.5 (IQR 5.0) mm for all axes combined. A significant postoperative reduction of TTTG was found in each group (p < 0.001). The mean change in TTTG did not differ significantly between the groups [- 8.8 (IQR 5.5) mm neutral, - 8.3 (IQR 7.0) mm valgus, - 7.5 (IQR 5.8) mm varus, p = 0.223]., Conclusion: This computer-based study suggests that mechanically aligned TKA significantly decreases TTTG distance in neutral, valgus and varus knees, assuming that the postoperative result coincides with the preoperative planning. Further study is warranted to evaluate the clinical relevance of this finding., (© 2022. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

Background: Since its first proposal, the concept of on- and off-track lesions in anterior shoulder instability has gained clinical relevance as a tool to predict the failure rate of arthroscopic Bankart repair. Current literature only reports either short-term follow-up or long-term results of small sample sizes. The aim of this study was to provide a long-term evaluation of recurrent instability following arthroscopic Bankart repair in a large cohort using the on-track vs. off-track concept as a predictor for failure., Methods: We retrospectively analyzed 271 patients who underwent primary arthroscopic Bankart repair for anterior shoulder instability between 1998 and 2007. All patients with a minimum follow-up of 78 months and a preoperative computed tomographic (CT) or magnetic resonance imaging (MRI) scan were included into the study. Preoperative CT and/or MRI scans were used to determine the glenoid track and width of Hill-Sachs lesion. Recurrence of instability was defined as presence of instability symptoms (dislocation, subluxation, and/or apprehension) or revision surgery (stabilization procedure) and was assessed as the primary outcome parameter., Results: The glenoid track of 163 shoulders was assessed (female n = 51, male n = 112) with a mean follow-up of 124 months (99.4-145.6, standard deviation = 2.5) and a mean age of 24 years (20-34.). An off-track Hill-Sachs lesion was found in 77 cases (47%), and in 86 cases (53 %) it was on-track. The rate of recurrent instability in the off-track group was 74% (n = 57) compared with 27% (n = 23) in the on-track group (P < .001). The overall rate of revision surgery due to instability was 29% (n = 48) after a mean time of 50.9 months (±42.8) following Bankart repair. The rate of revision surgery in the off-track group was 48% (n = 37) after a mean of 53.5 months (±42.0) vs. 13% (n = 11) after 42.3 months (±46.3) in the on-track group (P < .001)., Conclusion: This study shows that the on- and off-track concept helps to distinguish patients for whom an isolated arthroscopic Bankart repair yields long-term benefits. Because of the high rate of recurrent instability in the off-track group, an off-track lesion should be treated surgically in such a way that the off-track lesion is converted into an on-track lesion., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: The best treatment of degenerative hip abductor tendon lesions remains largely unknown, as the natural course of the disease has not yet been reported. The aim of the present study was to investigate the natural history of symptomatic degenerative hip abductor lesions., Hypothesis: Nonoperatively treated hip abductor lesions progress over time, resulting in refractory hip pain and low functional outcomes., Study Design: Case series (prognosis); Level of evidence, 4., Methods: Consecutive patients with greater trochanteric pain syndrome and degenerative changes on magnetic resonance imaging (MRI) of the symptomatic hip were included. Bilateral hip MRI scans and a clinical examination were performed at a minimum follow-up of 36 months to study the type and location of hip abductor lesion. Progression of a lesion was defined as a more severe lesion as compared with the initial MRI results or if the lesion extended to another, initially not involved, trochanteric facet. The muscle's fatty infiltration (FI) was also described., Results: From 106 patients identified, 58 patients (64 hips) aged 66 ± 14 years (mean ± SD) agreed to return to the clinic for follow-up MRI and met the inclusion criteria. At a mean 71-month follow-up, an overall 34% (22/64) of lesions had progressed over time: from trochanteric bursitis to tendinopathy (9/64, 14%) or partial tear (5/64, 8%), from tendinopathy to partial tear (4/64, 6%), from a partial to complete tear (3/64, 4.5%), and with 1 complete tear (1/64, 1.5%) extending to another trochanteric facet. Interestingly, 90% of partial tears remained stable or transformed into a scar. Although patients with a progressive lesion experienced more trochanteric pain (visual analog scale, 4.6 vs 2.8; P = .001), the functional outcomes were comparable with patients with a stable lesion. The majority of hips with a partial tear (64%) demonstrated a progression of gluteus minimus FI from a median grade of 1 to 2, whereas only 1 hip (3%) progressed from grade 2 to 3. Only 3 hips (9%) with a partial tear had a progression of gluteus medius FI, which did not differ significantly from the contralateral unaffected side., Conclusion: Nonoperative treatment might be a valid long-term option for degenerative hip abductor lesions, especially for partial tears, which demonstrated a low risk of clinically relevant progression or muscle FI and similar clinical outcomes to those reported in the literature for operatively treated hip abductor tendon lesions.

Case: We report the case of a 35-year-old patient who presented with a septic residual synovial cavity infection 8 weeks after a through-the-knee amputation because of a parosteal sarcoma. An endoscopic evacuation of the turbid fluid and synovial debridement through parapatellar portals as in a standard knee arthroscopy was performed, in conjunction with appropriate antibiotic therapy. One year postoperatively, there were no signs of residual infection., Conclusion: Endoscopic treatment of a septic stump infection of the residual synovial cavity after through-the-knee amputation is feasible. In our case, this approach resulted in rapid wound healing and early prosthesis mobility., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSCC/B971)., (Copyright © 2022 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)

Background: Biomechanical studies have shown a higher compressive force and higher torsional stiffness for fixation with three screws compared to two screws. However, clinical data to compare these fixation techniques is still lacking., Methods: A retrospective analysis of 113 patients was performed, who underwent isolated subtalar fusion between January 2006 and April 2018., Results: Revision arthrodesis was required in 8% (n=6/36) for 3-screw-fixation and 38% (n=35/77) for 2-screw-fixation. For 3-screw-fixation, non-union, was observed in 14% (n=5/36) compared to 35% (n=27/77) in 2-screw fixation. Non-union (p=.025) and revision arthrodesis (p=.034) were significantly more frequent in patients with 2 screws. A body mass index ≥30kg/m 2 (p=.04, OR=2.6,95%CI:1.1-6.3), prior ankle-fusion (p=.017,OR=4.4,95%CI:1.3-14.5) and diabetes mellitus (p=.04,OR=4.9,95%CI:1.1-17.8) were associated with a higher rate of revision arthrodesis., Conclusions: Our findings suggest that successful subtalar fusion is more reliably achieved with use of three screws. However, future prospective studies will be necessary to further specify this recommendation., (Copyright © 2019 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.)

Background: An optimal osteotomy angle avoids shortening of the first metatarsal bone after hallux valgus surgery and therefore reduces the risk of transfer-metatarsalgia. The purpose of the present ex-vivo study was to investigate whether augmented reality (AR) would improve accuracy of the distal osteotomy during hallux valgus surgery., Methods: Distal osteotomies of the first metatarsals were performed on a foot model by two surgeons with different levels of surgical experience each with (AR, n = 15 × 2) or without (controls, n = 15 × 2) overlay of a hologram depicting an angle of osteotomy perpendicular to the second metatarsal. Subsequently, the deviation of the osteotomy angle in the transverse plane was analyzed., Results: Overall, AR decreased the extent of deviation and the AR guided osteotomies were more accurate (4.9 ± 4.2°) compared to the freehand cuts (6.7 ± 6.1°) by tendency (p = 0.2). However, while the inexperienced surgeon performed more accurate osteotomies with AR with a mean angle of 6.4 ± 3.5° compared to freehand 10.5 ± 5.5° (p = 0.02), no significant difference was noticed for the experienced surgeon with an osteotomy angle of around 3° in both cases., Conclusion: This pilot-study suggests that AR guided osteotomies can potentially improve accuracy during hallux valgus correction, particularly for less experienced surgeons.

Purpose: To evaluate 3D-printed anatomic models of the distal femur and patella for diagnosis and classification of patellofemoral dysplasia in comparison to conventional radiographs (CR) and CT., Method: Following local ethics committee approval, CT-datasets of 50 patients were segmented and 3D-anatomic models of the distal femur and patella were printed. An expert panel reviewed CR, CT, 3D-models and patient history and classified the femoral trochleas into normal or Dejour type A-D and the patellas into Wiberg type A-C, which served as the standard of reference. The same classifications were performed by two readers independently, first based on 3D-models and after 3 weeks based on CR and CT. Descriptive statistics, ROC-analysis and inter-reader reliability were performed., Results: Trochlear dysplasia was present in 28/50 patients. Evaluations of 3D-models vs. CR/CT for trochlear dysplasia showed a sensitivity/specificity of 89.3 %/100 % vs. 96.4 %/68.2 % for reader 1 and 96.4 %/100 % vs. 96.4 %/90.9 % for reader 2, and an area under the curve of 0.946 vs. 0.823 for reader 1 (p = 0.029) and 0.982 vs. 0.937 for reader 2 (p = 0.147). Evaluations of 3D-models vs. CR/CT for the Dejour classification showed a sensitivity/specificity of 32.1 %/100 % vs. 57.1 %/68.2 % for reader 1 and 46.4 %/100 % vs. 50 %/90.9 % for reader 2 without significant differences. No significant differences existed for Wiberg-classification (50-66 % exact matches) or inter-reader reliabilities between 3D-models and CR/CT for all assessments (Kappa 0.428-0.92)., Conclusion: In comparison to radiographs and CT, 3D-models achieve similar diagnostic accuracy for detection of patellofemoral dysplasia and have the potential to improve diagnosis for less experienced physicians., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Subgroup analyses of the Latarjet procedure have suggested that age over 40 years is a risk factor for dislocation arthropathy., Purpose: To analyze long-term results of the open Latarjet procedure for recurrent anterior shoulder dislocation in patients at least 40 years of age., Study Design: Case series; Level of evidence, 4., Methods: A total of 39 consecutive patients (40 shoulders) with a mean age of 48 years (range, 40-66 years) at surgery were evaluated at a mean follow-up of 11.0 years (range, 8-16 years). Of these, 15 patients (38%) had undergone previous soft tissue stabilization surgery. Long-term results were assessed clinically and radiographically, including computed tomography scanning at final follow-up., Results: No recurrence of dislocation was noted. Subluxation had occurred in 3 patients (8%), and apprehension persisted in 5 patients (13%). The total Walch-Duplay score averaged 89 points at the final follow-up, and the mean Subjective Shoulder Value (60%-91%) had improved significantly ( P < .001). In total, 36 patients rated their result as excellent, 3 as good. Further, 6 patients (15%) underwent joint-preserving reoperation, and 1 patient (3%) had reverse total shoulder arthroplasty for severe dislocation arthropathy. Dislocation arthropathy was severe in 14 patients (37%) and had progressed by at least 2 grades in 17 patients (45%). Patients with severe dislocation arthropathy had already shown degenerative changes preoperatively as opposed to those who ultimately had no or moderate dislocation arthropathy (n = 24) ( P < .001). Progression of dislocation arthropathy was associated with lateral (>1 mm) graft positioning ( P < .001) and older age at surgery ( r = 0.58; P < .001)., Conclusion: The open Latarjet procedure for recurrent anterior shoulder instability in patients older than 40 years reliably restores stability and leads to high patient satisfaction. This procedure is, however, associated with a substantial rate of advanced but clinically mild symptomatic dislocation arthropathy, which is associated with the degree of preoperative joint degeneration, older age at surgery, and lateral graft placement.

Background: Several risk factors for adult acquired flatfoot deformity (AAFD) have been identified in literature. To this date, little attention has been paid to the lateral ligament complex and its influence on AAFD, although its anatomic course and anatomic studies suggest a restriction to flatfoot deformity. The aim of this study was to assess the influence of the anterior talofibular ligament (ATFL) on AAFD and on radiologic outcome following common operative correction by lateral calcaneal lengthening., Methods: We reviewed all patients that underwent lateral calcaneal lengthening for correction of AAFD between January 2008 and July 2018 at our clinic. Patients were grouped according to the preoperative MRI findings into those with an intact ATFL and those with an injured ATFL. Two independent readers assessed common radiographic flatfoot parameters on preoperative and postoperative radiographs., Results: Sixty-four flatfoot corrections in 63 patients were included, whereby the ATFL was intact in 29 cases, and in 35 cases the ligament was injured. An ATFL lesion was overall radiologically associated with increased flatfoot deformity with a statistically significant difference between the two groups for preoperative talometatarsal-angle (p = 0.002), talocalcaneal-angle (p = 0.000) and talonavicular uncoverage-angle (p = 0.005). No difference between the two groups could be observed regarding the success of operative correction or operative consistency after lateral calcaneal lengthening., Conclusion: The ATFL seems to influence the extent of AAFD. In patients undergoing lateral calcaneal lengthening, the integrity of the ligament seems not to influence the degree of correction or the consistency of the postoperative result.

OBJECTIVE. The anchoring of the medial meniscus is consistent, whereas the attachment of the lateral meniscus is variable. On routine MRI examinations, we analyzed the prevalence of a distinct fibrous connection between the anterolateral aspect of the lateral meniscus and the iliotibial band-which we have termed the "accessory iliotibial band-meniscal ligament" or "AIML"-and investigated an association between lesions of the lateral meniscus and the presence of an AIML. MATERIALS AND METHODS. We retrospectively reviewed 1019 knee MRI examinations for lesions of the lateral meniscus, presence and morphology of an AIML, and Hoffa edema. Descriptive statistics were applied and univariate analyses were performed to assess the association between the presence of an AIML and meniscal lesions as well as Hoffa edema. RESULTS. An AIML was present, with a mean length of 22.8 mm (range, 12.9-36.8 mm; SD, 5.8 mm), in 13.3% of the patients (136/1019). A lesion of the anterior horn of the lateral meniscus was recorded in 1.2% of patients without an AIML (11/883) and 23.5% of patients with an AIML (32/136; p < 0.001). A lesion of the lateral meniscus body was found in 1.6% of patients without an AIML ( n = 14/883) and 16.2% of patients with an AIML (22/136, p < 0.001). Hoffa edema was seen in 0.2% of patients without an AIML (2/883) and 14.0% of patients with an AIML (19/136; p < 0.001). CONCLUSION. The AIML represents an anatomic variant of fixation of the lateral meniscus that is strongly associated with lesions of the lateral meniscus and Hoffa edema.

The subtalar joint plays an important role for the hindfoot when accommodating during gait. Joint degeneration may be caused by posttraumatic, inflammatory, and pathologic biomechanical changes. Once conservative treatment has failed, subtalar fusion should be considered. The indication for surgery is based on thorough clinical and radiographic evaluation. Several techniques for subtalar fusion are published in literature. This article aims to describe a technique for in situ arthrodesis of the subtalar joint, paying special attention to biomechanical aspects as well as preoperative clinical and radiological work-up., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Various operative techniques are used for treating recurrent anterior shoulder instability, and good mid-term results have been reported. The purpose of this study was to compare shoulder stability after treatment with the 2 commonly performed procedures, the arthroscopic Bankart soft-tissue repair and the open coracoid transfer according to Latarjet., Methods: A comparative, retrospective case-cohort analysis of 360 patients (364 shoulders) who had primary repair for recurrent anterior shoulder instability between 1998 and 2007 was performed. The minimum duration of follow-up was 6 years. Reoperations, overt recurrent instability (defined as recurrent dislocation or subluxation), apprehension, the subjective shoulder value (SSV), sports participation, and overall satisfaction were recorded., Results: An open Latarjet procedure was performed in 93 shoulders, and an arthroscopic Bankart repair was done in 271 shoulders. Instability or apprehension persisted or recurred after 11% (10) of the 93 Latarjet procedures and after 41.7% (113) of the 271 arthroscopic Bankart procedures. Overt instability recurred after 3% of the Latarjet procedures and after 28.4% (77) of the Bankart procedures. In the Latarjet group, 3.2% of the patients were not satisfied with their result compared with 13.2% in the Bankart group (p = 0.007). Kaplan-Meier analysis of survivorship, with apprehension (p < 0.001), redislocation (p = 0.01), and operative revision (p < 0.001) as the end points, documented the substantial superiority of the Latarjet procedure and the decreasing effectiveness of the arthroscopic Bankart repair over time. Twenty percent of the first recurrences after arthroscopic Bankart occurred no earlier than 91 months postoperatively, as opposed to the rare recurrences after osseous reconstruction, which occurred in the early postoperative period, with only rare late failures., Conclusions: In this retrospective cohort study, the arthroscopic Bankart procedure was inferior to the open Latarjet procedure for repair of recurrent anterior shoulder dislocation. The difference between the 2 procedures with respect to the quality of outcomes significantly increased with follow-up time., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background: Heterotopic ossification (HO) is a frequent complication following orthopedic and trauma surgery. It often leads to substantial morbidity as many affected patients suffer from pain and joint contractures. Current prophylactic measures include nonsteroidal anti-inflammatory drugs (NSAID) and local radiation. However, several disadvantages such as delayed fracture healing and impaired ossification have been reported. For this reason, a novel approach for prevention of HO was searched for. We hypothesized that systemic administration of hydroxyethyl starch (HES), a substance known to influence microcirculation, would reduce formation of HO in a murine model., Methods: A pre-established murine model was used where HO has been shown to develop following Achilles tendon tenotomy. Twenty CD1 mice were randomly assigned to a control (n = 10) or treatment group (n = 10). The treatment group received two intravenous HES injections perioperatively, while the control group underwent tenotomy only. After ten weeks, the mice were euthanized and micro CT scans of the hind limbs were performed. HO was manually identified and quantitatively assessed. A Wilcoxon rank sum test was used for comparison of both groups., Results: The mean heterotopic bone volume in the control group was significantly larger compared to the HES group (2.276 mm(3) vs. 0.271 mm(3), p = 0.005). A reduction of mean ectopic bone volume of 88 % was found following administration of HES., Conclusion: A substantial reduction of HO formation was found following perioperative short-term administration of HES. This work represents a preliminary study, necessitating further studies before drawing ultimate conclusions. However, this simple addition to current prophylactic measures might lead to a more effective prevention of HO in the future.

Background: There is a need for effective drugs in the prevention and treatment of heterotopic ossifications (HO) after fractures. Echinomycin has been shown to prevent formation of HO in an animal model. However, before it may be considered as an option against HO, it needs to be studied whether it prevents fracture healing similar to non-steroidal anti-inflammatory drugs (NSAIDS). Therefore, the hypothesis was that echinomycin prevents fracture healing and callus formation., Methods: In an experimental murine pilot study, standard blunt femur fractures were induced and retrograde intramedullary compression fixation of the femur was performed. The treatment group (n = 8) received echinomycin (0.3 mg/kg body weight) and the control group (n = 8) did not receive echinomycin. The fractures and implant positions were verified by conventional X-rays immediately postoperatively. As the primary outcome variable, fracture healing (osseous consolidation) was evaluated by conventional X-rays and micro-computed tomography (CT) scans after ten weeks and graded as healed, partial or complete pseudarthrosis. The secondary outcome, callus formation, was graded semi-quantitatively from 0 (mostly absent) to 3 (maximum)., Results: Fracture healing was present in all living cases after ten weeks concerning the treatment group. Partial pseudarthrosis was seen in two cases, one in the treatment and another one in the control group. Complete pseudarthrosis was seen in one case of the control group after an open fracture. Callus formation was similar in both groups with a mean grade of 1.5 within each group. Two cases of the treatment group died., Conclusion: As a novel finding, echinomycin did not inhibit fracture healing or callus formation in this in vivo murine standard femur fracture model pilot study. Further studies involving a larger number of cases, quantitative assessment with CT scans and histopathological analysis are needed before generalizing the results of this pilot study.

Background: The quantification of a subscapularis tendon lesion may be difficult on magnetic resonance imaging, as well as during arthroscopic inspection. Consequently, the surgical decision of whether to only debride a degenerated tendon or to lateralize the more intact tendon portion may be arbitrary. This study aims to quantify the length of the subscapularis tendon as a sign of partial tendon tearing., Methods: We retrospectively identified 92 magnetic resonance arthrography studies of suspected rotator cuff lesions obtained 3 months before shoulder arthroscopy. The myotendinous junction was identified, and the subscapularis tendon and muscle lengths were measured. Findings on arthroscopy performed later were used as the diagnostic gold standard for tendon integrity and compared with the magnetic resonance data., Results: Arthroscopy showed an intact subscapularis tendon in 43 patients, tendinopathy in 21 patients, and a partial rupture in 28 patients. The mean subscapularis tendon lengths were 40 mm in cases of intact subscapularis musculotendinous units, 45 mm in cases of tendinopathy, and 53 mm in cases of partial tears, whereas the mean subscapularis muscle lengths were 105 mm, 94 mm, and 95 mm, respectively, in these groups., Conclusion: Partial tears of the subscapularis tendon lead to muscle shortening by approximately 10% and elongation of the tendon by approximately 32%, which may be interpreted as muscle retraction and a tendon rupture in continuity. If the subscapularis tendon has an apparent length of greater than 60 mm, the probability of a tear is 98%. Determination of the tendon length may therefore be a useful additional tool to quantify the integrity of the subscapularis tendon and degree of myotendinous retraction., (Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Background: The influence of high blood alcohol level (BAL) on the outcome of severely injured patients and the corresponding pathophysiological changes is a controversial issue., Objective: To carry out a prognostic study to compare the physiological values and short-term outcome of severely injured patients depending on their serum alcohol level., Methods: A total of 383 severely injured patients with an Injury Severity Score (ISS) ≥17 were admitted to the trauma division between October 2008 and December 2009 and enrolled into this study. Patients were grouped according to their BAL (>0.5‰,'BAL positive' vs <0.5‰,'BAL negative'). Trauma mechanism, pattern of injury and its treatment, and a course of intensive care treatment, physiological parameters and outcome with respect to mortality were analysed., Results: Both groups had similar ISS. In comparison with the BAL-negative group, patients in the BAL-positive group had a significantly lower Glasgow Coma Scale score (9.64 vs 12 points; p=0.005) and, although not significant, a trend towards higher values of the Abbreviated Injury Score for the head (3.29 vs 2.81 points; p=0.146). Furthermore, significantly higher lactate (3.11 mmol/L vs 2.02 mmol/L; p<0.001) levels and lower median arterial pressure values (87.9 mm Hg vs 99.4 mm Hg; p=0.006) were seen in the BAL-positive group at day of admission. However, the overall in-hospital mortality was comparable to that in BAL-negative patients (19.6% vs 21.5%). Similarly, hospital stay (15.29 vs 17.55 days) and duration of intensive care unit treatment (8.53 vs 8.36 days) were not significantly affected by a high BAL upon admission., Conclusions: Severely injured patients with a raised BAL have a higher incidence of severe traumatic brain injury and worse initial physiological parameters. However, the survival rate and in-hospital stay is not influenced. This supports the theory of a neuroprotective role of alcohol., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Injuries of the axial skeleton are an important field of work within orthopaedic surgery and traumatology. Most lesions following trauma may be diagnosed by means of conventional plain radiography, computed tomography or magnetic resonance imaging. However, for some aspects SPECT/ CT can be helpful even in a trauma setting. In particular, the combination of highly sensitive but nonspecific scintigraphy with nonsensitive but highly specific computed tomography makes it particularly useful in anatomically complex regions such as the pelvis and spine. From a trauma surgeon's point of view, the four main indications for nuclear medicine imaging are the detection of (occult) fractures, and the imaging of inflammatory bone and joint diseases, chronic diseases and postoperative complications such as instability of instrumentation or implants. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical setting.

Background: Fractures of the pelvic ring including disruption of the posterior elements in high-energy trauma have both high morbidity and mortality rates. For some injury pattern part of the initial resuscitation includes either external fixation or plate fixation to close the pelvic ring and decrease blood loss. In certain situations--especially when associated with abdominal trauma and the need to perform laparotomies--both techniques may put the patient at risk of either pintract or deep plate infections. We describe an operative approach to percutaneously close and stabilize the pelvic ring using spinal implants as an internal fixator and report the results in a small series of patients treated with this technique during the resuscitation phase., Findings: Four patients were treated by subcutaneous placement of an internal fixator. Screw fixation was carried out by minimally invasive placement of two supra-acetabular iliac screws. Afterwards, a subcutaneous transfixation rod was inserted and attached to the screws after reduction of the pelvic ring. All patients were allowed to fully weight-bear. No losses of reduction or deep infections occurred. Fracture healing was uneventful in all cases., Conclusion: Minimally invasive fixation is an alternative technique to stabilize the pelvic ring. The clinical results illustrate that this technique is able to achieve good results in terms of maintenance of reduction the pelvic ring. Also, abdominal surgeries no longer put the patient at risk of infected pins or plates.

Background: Odontoid fractures account for approximately 20% of all fractures of the cervical spine. They represent the most common cervical spine injury for patients older than 70 years, the majority being type II fractures (65-74%), which are considered to be relatively unstable. The management of these fractures is controversial. Possible treatment options are either conservative or surgical. Surgical procedures include either anterior screw fixation of the odontoid or posterior C1/C2 fusion. The aim of this study was to compare the outcome of the three treatment modalities in elderly patients., Methods: Between June 2004 and February 2010, all patients older than 65 years (n = 47) with type II fractures of the odontoid according to the Anderson and D'Alonso classification were retrospectively reviewed., Results: In the non-operatively managed cohort, 11 patients (79%) died postoperatively within a mean period of 23 months. In all other cases (n = 3), radiographs demonstrated non-union. The mean lateral displacement was 1.9 mm (range 0-5,8 mm) and a mean angulation of 29,1° (range 0-55°) was found.Anterior screw fixation was carried out in 17 patients. The non-union rate in this cohort was 77%. In patients with a posterior C1-C2 fusion, a bony fusion of the posterior elements was found in 15 of 16 cases (93%). Survival rates were significantly higher among the group of patients who were treated with anterior screw fixation or posterior C1/C2 fusion compared to the conservatively treated group., Conclusion: We found the best clinical results with low rates of non-union as well as low mortality rates following posterior C1/C2 fusion making this our treatment of choice especially in an elderly patient collective.

Background: Heterotopic ossification (HO) is a common complication following orthopedic and trauma surgery, which may have substantial negative effects on the postoperative outcome. Angiogenesis appears to play a critical role in heterotopic ossification. One of the involved signaling molecules is platelet-derived growth factor (PDGF) which may be inhibited by imatinib., Questions/purposes: Our goal was to prevent HO by pharmacologically interfering with the molecular signaling pathways involved in the developmental process. We hypothesized that by administering a proven inhibitor of PDGF expression, heterotopic bone formation may be prevented., Methods: The effect of imatinib on HO formation was studied in a murine model which reliably produces islets of HO within the soft tissue following Achilles tenotomy. The control group underwent Achilles tenotomy only. The imatinib group received imatinib mesylate. After trial completion, the limbs were harvested and scanned by micro-CT. Heterotopic bone volume was then identified and quantified., Results: The mean volume of heterotopic bone formed in the control group was 0.976mm(3) compared to 0.221 mm(3) in the imatinib group. The volume of HO in the treatment group was reduced by 85% compared to the control group., Conclusions: The administration of imatinib was associated with a significantly reduced volume of HO. This may be due to the inhibitory effect of imatinib on the PDGF signaling pathway during development of HO., Clinical Relevance: The successful reduction of HO formation following imatinib administration has led to further insight concerning the pathogenesis of HO which in the future may lead to new clinical approaches towards the prevention of HO.

Background: Heterotopic ossification (HO) frequently causes complications following orthopaedic and trauma surgery and may drastically reduce the postoperative outcome due to pain and joint contracture. Current therapeutic options include NSAID's and local radiation. However, both options of prevention show disadvantages such as delayed fracture healing and impaired ossification as well as other side effects.(9) Our goal was to investigate a novel approach in the prevention of heterotopic ossification by pharmacologically interfering with the molecular signalling pathways involved in this process. Hypoxia leads to numerous effects on a cellular level, one of which is the activation of the transcriptional complex hypoxia-inducible factor (HIF).(19) Among several other actions, the HIF1-α signalling pathway in turn regulates angiogenesis through induction of the expression of vascular endothelial growth factor (VEGF).(21) We hypothesised that by pharmacologically interfering with the HIF-1α signalling pathway, the amount of HO formation may be reduced. Echinomycin is a known inhibitor of HIF-1-alpha and was used in our study with the aim to prevent HO from forming., Methods: We examined the effect of Echinomycin on HO formation in a murine model where an Achilles tenotomy was performed. This has previously been shown to reliably produce islets of heterotopic ossification within the soft tissue of mouse hind limbs at 10 weeks after surgery. The control group underwent Achilles tenotomy only, whereas the Echinomycin group additionally received Echinomycin subcutaneously. After trial completion, the limbs were harvested and Micro-CT was performed. Heterotopic bone volume was then identified in 3d images and quantified., Results: We found a highly significant reduction in the bone volume following subcutaneous administration of Echinomycin compared to the control group., Conclusion: Although a substantial reduction could be achieved, it was not possible to completely prevent heterotopic ossification from forming. Further studies have yet to be conducted to optimise the results by altering the dosage and duration of administration as well as investigate the mechanism by which Echinomycin led to the reduction of HO formation., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Introduction. Sternal fractures often occur together with serious and life-threatening additional injuries. This retrospective study was designed to assess concomitant injuries and develop a correlation between fracture location and the severity of injury. Methods. All patients (n = 58) diagnosed with a fracture of the sternum by means of a CT scan were analysed with respect to accident circumstances, fracture morphology and topography, associated injuries, and outcome. Results. Isolated sternal fractures occurred in 9%. In all other admissions, concomitant injuries were diagnosed: mainly rip fractures (64%), injury to the head (48%), the thoracic spine (38%), lumbar spine (27%), and cervical spine (22%). Predominant fracture location was the manubrium sterni. In these locations, the observed mean ISS was the highest. They were strongly associated with thoracic spine and other chest injuries. Furthermore, the incidence of head injuries was significantly higher. ICU admission was significantly higher in patients with manubrium sterni fractures. Conclusion. Sternal fractures are frequently associated with other injuries. It appears that the fracture location can provide important information regarding concomitant injuries. In particular, in fractures of manubrium sterni, the need for further detailed clinical and radiologic workup is necessary to detect the frequently associated injuries and reduce the increased mortality.

We retrospectively analyzed CT scans of 620 individuals, who presented to our traumatology department between 2008 and 2010. Facet joint (FJ) arthritis was present in 308 (49.7%) individuals with a mean grade of 1. It was seen in 27% of individuals ≤40 years and in 75% of individuals ≥41 years (P < 0.0001) as well as in 52% of females and 49% of males (P = 0.61). Mean FJ orientation was 30.4° at L2/3, 38.7° at L3/4, 47° at L4/5, and 47.3° at L5/S1. FJ arthritis was significantly associated with more coronal (increased degree) FJ orientation at L2/3 (P = 0.03) with a cutoff point at ≥32°. FJs were more coronally oriented (48.8°) in individuals ≤40 years and more sagittally oriented (45.6°) in individuals ≥41 years at L5/S1 (P = 0.01). Mean FJ asymmetry was 4.89° at L2/3, 6.01° at L3/4, 6.67° at L4/5, and 7.27° at L5/S1, without a significant difference for FJ arthritis. FJ arthritis is common, increases with age, and affects both genders equally. More coronally oriented FJs (≥32°) in the upper lumbar spine may be an individual risk factor for development of FJ arthritis.

The human surface antigen CD24 is over-expressed in small-cell lung cancer. Here we describe the isolation, sequencing and functional characterization of the 5'-flanking region of the human CD24 gene. A sequence (accession number: Y14692) of 3.4 kb regulates the activity of a luciferase reporter gene in CD24-expressing small-cell-lung-cancer cell lines up to 1.6-fold more than the control SV40 promoter and enhancer. In contrast, little or no luciferase activity was detected in 4 non-small-cell-lung-cancer cell lines. A deletion fragment of 269 bp had maximal activity in small-cell-lung-cancer cell lines (15- to 20-fold higher than control), while activity remained 2- to 10-fold below control in non-small-cell-lung-cancer cell lines. We conclude that the CD24 promoter has a strong and cell-type-specific activity, and propose its exploitation to drive the expression of therapeutic genes in small-cell lung cancer.

Human CD24 is a highly glycosylated glycosylphosphatidylinositol-linked (GPI-linked) cell surface protein. GPI-linked proteins are involved in signal transduction mediated by members of the protein tyrosine kinase (PTK) family. Therefore we studied associated molecules providing the signaling capacity of CD24. Lysates of SW2 and K562 cells were analysed for expression of PTK of the c-src family by Western blotting. We identified c-fgr in SW2 lysates and c-fgr and also lyn in K562 lysates. To study a putative association of these PTK with CD24 we performed immunoprecipitations with the mAb SWA11 directed against CD24. Western analysis of the precipitates showed an association of c-fgr with CD24 in SW2 cells and lyn in K562 cells. We conclude that either c-fgr or lyn is physically associated with CD24 in a cell-type depending manner. An involvement of these complexes in signaling phenomenons of CD24 in small cell lung cancer and in leukaemias is discussed.