Patellofemoral cartilage defects are acceptable in patients undergoing high tibial osteotomy for medial osteoarthritis of the knee.

BACKGROUND: Patients suffering cartilage defects of the medial compartment with underlying varus deformity do benefit from high tibial osteotomy (HTO) even in the long term. Nonetheless, kinematic and geometric changes especially in the patellofemoral joint have been described. Purpose of the present study was to evaluate the influence of patellofemoral cartilage defects detected during the diagnostic arthroscopy and their influence on HTO's postoperative outcome. METHODS: Ninety patients with a mean follow-up of 10.08 ± 2.33 years after surgery were included. Patients were divided into four groups according to their cartilage status in the patellofemoral joint (A = no defects, B = isolated lesions of the patella, C = isolated lesions of the trochlea, D = kissing lesions). Functional outcome was evaluated before surgery and about ten years thereafter by relying on the IKDC, Lysholm, and KOOS scores. Radiological parameters were assessed pre- and six weeks postoperatively. RESULTS: In groups A to D, the HTO led to significant patellar distalisation in the sagittal view, with the mean indices remaining at or above the limit to a patella baja. All patients in all groups profited significantly from HTO (higher Lysholm score, lower VAS p < 0.001), patients in group D had the lowest outcome scores. Patella height negatively influenced outcome scores in group C (Blackburne-Peel-Index-VAS p = 0.033) and D (Caton-Deschamps-Index-Tegner p = 0.018), a larger valgus correction was associated with lower outcome scores in group D (Lysholm p = 0.044, KOOSpain 0.028, KOOSQOL p = 0.004). CONCLUSION: Long-term results of HTO for varus medial compartment osteoarthritis remain good to excellent even in the presence of patellofemoral defects. Overcorrection should be avoided. Distal biplanar HTO should be considered for patients presenting trochlear or kissing lesions of the patellofemoral joint. TRIAL REGISTRATION: DRKS00015733 in the German Registry of Clinical Studies.

Low-profile double plating of unstable osteoporotic olecranon fractures: a biomechanical comparative study.

BACKGROUND: In the treatment of unstable olecranon fractures, anatomically preshaped locking plates exhibit superior biomechanical results compared with tension band wiring. However, posterior plating (PP) still is accompanied by high rates of plate removal because of soft-tissue irritation and discomfort. Meanwhile, low-profile plates precontoured for collateral double plating (DP) are available and enable muscular soft-tissue coverage combined with angular-stable fixation. The goal of this study was to biomechanically compare PP with collateral DP for osteosynthesis of unstable osteoporotic fractures. METHODS: A comminuted displaced Mayo type IIB fracture was created in 8 osteoporotic pairs of fresh-frozen human cadaveric elbows. Pair-wise angular stable fixation was performed by either collateral DP or PP. Biomechanical testing was conducted as a pulling force to the triceps tendon in 90° of elbow flexion. Cyclical load changes between 10 and 300 N were applied at 4 Hz for 50,000 cycles. Afterward, the maximum load was raised by 0.02 N/cycle until construct failure, which was defined as displacement > 2 mm. Besides failure cycles and failure loads, modes of failure were analyzed. RESULTS: Following DP, a median endurance of 65,370 cycles (range, 2-83,121 cycles) was recorded, which showed no significant difference compared with PP, with 69,311 cycles (range, 150-81,938 cycles) (P = .263). Failure load showed comparable results as well, with 601 N (range, 300-949 N) after DP and 663 N (range, 300-933 N) after PP (P = .237). All PP constructs and 3 of 8 DP constructs failed by proximal fragment cutout, whereas 5 of 8 DP constructs failed by bony triceps avulsion. CONCLUSION: Angular-stable DP showed comparable biomechanical stability to PP in unstable osteoporotic olecranon fractures under high-cycle loading conditions. Failure due to bony triceps avulsion following DP requires further clinical and biomechanical investigation, for example, on suture augmentation or different screw configurations.

Arthroscopic Bankart repair with an individualized capsular shift restores physiological capsular volume in patients with anterior shoulder instability.

PURPOSE: Capsular volume reduction in the context of anterior arthroscopic shoulder stabilization represents an important but uncontrolled parameter. The aim of this study was to analyse capsular volume reduction by arthroscopic Bankart repair with an individualized capsular shift in patients with and without ligamentous hyperlaxity compared to a control group. METHODS: In the context of a prospective controlled study, intraoperative capsular volume measurements were performed in 32 patients with anterior shoulder instability before and after arthroscopic Bankart repair with an individualized capsular shift. The results were compared to those of a control group of 50 patients without instability. Physiological shoulder joint volumes were calculated and correlated with biometric parameters (sex, age, height, weight and BMI). RESULTS: Patients with anterior shoulder instability showed a mean preinterventional capsular volume of 35.6 ± 10.6 mL, which was found to be significantly reduced to 19.3 ± 5.4 mL following arthroscopic Bankart repair with an individualized capsular shift (relative capsular volume reduction: 45.9 ± 21.9%; P < 0.01). Pre-interventional volumes were significantly greater in hyperlax than in non-hyperlax patients, while post-interventional volumes did not differ significantly. The average shoulder joint volume of the control group was 21.1 ± 7.0 mL, which was significantly correlated with sex, height and weight (P < 0.01). Postinterventional capsular volumes did not significantly differ from those of the controls (n.s.). CONCLUSION: Arthroscopic Bankart repair with an individualized capsular shift enabled the restoration of physiological capsular volume conditions in hyperlax and non-hyperlax patients with anterior shoulder instability. Current findings allow for individual adjustment and intraoperative control of capsular volume reduction to avoid over- or under correction of the shoulder joint volume. Future clinical studies should evaluate, whether individualized approaches to arthroscopic shoulder stabilization are associated with superior clinical outcome.

Biodegradable magnesium vs. polylactide pins for radial head fracture stabilization: a biomechanical study.

BACKGROUND: Biodegradable implants have gained increasing importance for the fixation of simple displaced radial head fractures to supersede implant removal and to minimize cartilage destruction. Commonly used polylactide pins still lead to higher rates of secondary loss of reduction compared with metal implants. Alternatively, implants made from a magnesium alloy meanwhile are available in a pin design that hypothetically could perform better than polylactide pins. Because biomechanical data of clinical applications are lacking, the goal of the present study was to biomechanically compare magnesium pins to polylactide pins using a Mason type II radial head fracture model. METHODS: Fourteen pairs of fresh-frozen human cadaver radii with a standardized Mason type II radial head fracture were stabilized either by two 2.0-mm polylactide pins (PPs) or two 2.0-mm magnesium pins (MPs). Biomechanical in vitro testing was conducted as 10 cycles of static loading at 0.1 Hz axially and transversally between 10 and 50 N. Afterward, loosening was tested by dynamic load changes at 4 Hz up to 100,000 cycles. Early fracture displacement was measured after 10,000 cycles. Afterward, maximum loads were raised every 10,000 cycles by 15 N until construct failure, which was defined as fracture displacement ≥2 mm. RESULTS: MP osteosynthesis showed a tendency toward higher primary stability on both axial (MP: 0.19 kN/mm, PP: 0.11 kN/mm; P = .068) and transversal loading (MP: 0.11 kN/mm, PP: 0.10 kN/mm; P = .068). Early fracture displacement was significantly higher following PP osteosynthesis (MP: 0.3 mm, PP: 0.7 mm; P = .030). The superiority of MP was also significant during cyclic loading, represented in a higher failure cycle (MP: 30,684, PP: 5113; P = .009) and in higher failure loads (MP: 95 N, PP: 50 N; P = .024). CONCLUSION: According to our findings, in simple radial head fractures, osteosynthesis with magnesium pins show superior biomechanical properties compared with fractures treated by polylactide pins. Prospective investigations should follow to evaluate clinical outcomes and resorption behavior.

Biomechanical comparison of biodegradable magnesium screws and titanium screws for operative stabilization of displaced capitellar fractures.

BACKGROUND: Displaced fractures of the humeral capitellum are commonly treated operatively and fixed by titanium screws (TSs) either directly or indirectly. In the case of direct transcartilaginous fixation, biodegradable screws with the ability to be countersunk can be favorable regarding implant impingement and cartilage destruction. Hence, the goal of this study was to biomechanically compare headless compression screws made from titanium with a biodegradable equivalent made from a magnesium alloy. METHODS: This biomechanical in vitro study was conducted on 13 pairs of fresh-frozen human cadaveric humeri, in which a standardized Bryan-Morrey type I fracture was fixed using 2 magnesium screws (MSs) or 2 TSs. First, construct stiffness was measured during 10 cycles of static loading between 10 and 50 N. Second, continuous loading was applied at 4 Hz between 10 and 50 N, increasing the maximum load every 10,000 cycles by 25 N until construct failure occurred. This was defined by fragment displacement >3 mm. RESULTS: Comparison of the 2 screw types showed no differences related to construct stiffness (0.50 ± 0.25 kN/mm in MS group and 0.47 ± 0.13 kN/mm in TS group, P = .701), failure cycle (43,944 ± 21,625 and 41,202 ± 16,457, respectively; P = .701), and load to failure (152 ± 53 N and 150 ± 42 N, respectively; P = .915). CONCLUSION: Biomechanical comparison showed that simple capitellar fractures are equally stabilized by headless compression screws made from titanium or a biodegradable magnesium alloy. Therefore, in view of the advantages of biodegradable implants for transcartilaginous fracture stabilization, their clinical application should be considered and evaluated.

Possible advantages of early stabilization of spinal fractures in multiply injured patients with leading thoracic trauma - analysis based on the TraumaRegister DGU®.

BACKGROUND: Major trauma often comprises fractures of the thoracolumbar spine and these are often accompanied by relevant thoracic trauma. Major complications can be ascribed to substantial simultaneous trauma to the chest and concomitant immobilization due to spinal instability, pain or neurological dysfunction, impairing the respiratory system individually and together. Thus, we proposed that an early stabilization of thoracolumbar spine fractures will result in significant benefits regarding respiratory organ function, multiple organ failure and length of ICU / hospital stay. METHODS: Patients documented in the TraumaRegister DGU®, aged ≥16 years, ISS ≥ 16, AISThorax ≥ 3 with a concomitant thoracic and / or lumbar spine injury severity (AISSpine) ≥ 3 were analyzed. Penetrating injuries and severe injuries to head, abdomen or extremities (AIS ≥ 3) led to patient exclusion. Groups with fractures of the lumbar (LS) or thoracic spine (TS) were formed according to the severity of spinal trauma (AISspine): AISLS = 3, AISLS = 4-5, AISTS = 3 and AISTS = 4-5, respectively. RESULTS: 1740 patients remained for analysis, with 1338 (76.9%) undergoing spinal surgery within their hospital stay. 976 (72.9%) had spine surgery within the first 72 h, 362 (27.1%) later on. Patients with injuries to the thoracic spine (AISTS = 3) or lumbar spine (AISLS = 3) significantly benefit from early surgical intervention concerning ventilation time (AISLS = 3 only), ARDS, multiple organ failure, sepsis rate (AISTS = 3 only), length of stay in the intensive care unit and length of hospital stay. In multiple injured patients with at least severe thoracic spine trauma (AISTS ≥ 4) early surgery showed a significantly shorter ventilation time, decreased sepsis rate as well as shorter time spend in the ICU and in hospital. CONCLUSIONS: Multiply injured patients with at least serious thoracic trauma (AISThorax ≥ 3) and accompanying spine trauma can significantly benefit from early spine stabilization within the first 72 h after hospital admission. Based on the presented data, primary spine surgery within 72 h for fracture stabilization in multiply injured patients with leading thoracic trauma, especially in patients suffering from fractures of the thoracic spine, seems to be beneficial.

Expression of xylosyltransferases I and II and their role in the pathogenesis of arthrofibrosis.

BACKGROUND: Arthrofibrosis is a painful and restraining complication that occurs after about 10% of total knee arthroplasty and cruciate ligament surgery. The pathogenesis of arthrofibrosis has not yet been fully understood. Stress signals stimulate immune cells, and fibroblast differentiates into myofibroblast, which produce a large amount of collagen. Xylosyltransferases also appear to be involved in these pathways. They catalyze proteoglycan biosynthesis, which is involved in tissue remodeling and myofibroblast differentiation. The aim of this study was to investigate the relationship between the disease arthrofibrosis and the expression of the two isoforms of xylosyltransferases I and II. METHODS: Tissue samples from 14 patients with arthrofibrosis were compared with tissue samples from seven healthy controls. The xylosyltransferases were detected by immunohistochemistry. The tissues were divided into four different areas of interest: vessels, synovialis, cell-poor and cell-rich fibrosis, or cell-poor and cell-rich areas in the control group. A quantification of the results was performed by modification of the immunoreactive score according to Remmele and Stegner. RESULTS: Xylosyltransferase I was expressed in the various tissue types at varying rates. Xylosyltransferase I expression was considerably and significantly stronger than that of xylosyltransferase II. The following sequences of xylosyltransferase I and xylosyltransferase II expression were determined as follows: vessels >> cell-rich fibrosis > cell-poor fibrosis > synovialis. A positive correlation between the number of positive fibroblasts and the immunoreactive scoring system (IRS) was documented. CONCLUSIONS: The significant positive correlation of xylosyltransferase -I expression with increasing number of fibroblasts demonstrates a high myofibroblast differentiation rate, which implies a gradual event as the pathogenesis of arthrofibrosis.

Fluoroscopic guided tunnel placement during medial patellofemoral ligament reconstruction is not accurate in patients with severe trochlear dysplasia.

PURPOSE: Accurate femoral tunnel placement is of great importance during medial patellofemoral ligament (MPFL) reconstruction. Purpose of the present study was to investigate the influence of trochlear dysplasia on the accuracy of fluoroscopic guided femoral tunnel placement. METHODS: CT-Scans of 30 knees (five with regular shaped trochlea, 10 with a Type A and five each with a Type B, C, or D trochlear dysplasia) were imported into the image analysis platform MeVisLab. A 3D Bone Volume Rendering (VR) and a virtual lateral radiograph was created. The anatomic femoral MPFL insertion was identified on the 3D VR. On virtual lateral radiographs, the MPFL insertion was identified based on landmarks described by Schöttle et al. using three different perspectives: Best possible overlap of the femoral condyles (BC) and a tangent along posterior border of the posterior femoral cortex (pBC); a tangent along the anterior border of the posterior cortex (aBC); and best possible overlap of the distal part of the posterior femoral cortex (BF). Distances between the anatomic attachment and radiographically obtained insertions were measured on the 3D VR and compared according to the type of trochlear dysplasia. RESULTS: Significantly lower accuracy of fluoroscopy guided tunnel placement in MPFL reconstruction was found in knees with Type C and D dysplasia. This effect was observed irrespectively from the radiologic perspective (pBC, aBC, and FC). In the pBC view (highest accuracy), the mean distance from the centre of the anatomic MPFL attachment to the radiographically defined location was 4.3 mm in knees without trochlear dysplasia and increased to 4.8 mm in knees with Type A dysplasia, 3.8 mm in knees with Type B dysplasia, 6.7 mm (p < 0.001) in knees with Type C dysplasia, and 7.3 mm (p < 0.001) in knees with Type D dysplasia. CONCLUSION: Radiographic landmark-based femoral tunnel placement in the pBC view provides highest accuracy in knees with a normal shaped trochlea or low grade trochlear dysplasia. In patients with severe dysplasia, fluoroscopy guided tunnel placement has a low accuracy, exceeding a critical threshold of 5 mm distance to the anatomic MPFL insertion irrespective of the radiographic perspective. In these patients, utilization of anatomic landmarks may be beneficial. LEVEL OF EVIDENCE: IV.

Physical Performance and Quality of Life after Ankle Fusion. / Körperliche Leistungsfähigkeit und Lebensqualität nach Arthrodese des oberen Sprunggelenks.

INTRODUCTION: Ankle fusion is still considered as an established therapy for end-stage ankle osteoarthritis. To determine exact description of postoperative functioning, it is necessary to consult a variety of functional scores and quality of life questionnaires. METHODS/PATIENTS: 34 patients with 34 ankle fusions were investigated on average 5.9 years postoperatively by functional tests and health-related quality of life questionnaires (AOFAS hindfoot score [AOFAS: American Orthopaedic Foot/Ankle Society], Foot Function Index [FFI], Lower Extremity Functional Scale [LEFS], Lower Extremity Activity Scale [LEAS], Visual Analogue Scale Foot/Ankle Surgery [VAS FA], Short Form 36 [SF-36], EuroQol 5D [EQ-5D]). RESULTS: After ankle fusion: the majority of cases gain pain reduction, but residual symptoms may persist; the maximum walking distance (subjectively more than objectively) will be extended; rarely walking without any aids can be achieved; in most cases, the gait pattern is only slightly changed; the re-entry into working life is often possible; climbing stairs without any restrictions is not always possible; the psychological situation will be equalized with that of healthy people. CONCLUSION: The results of the study confirm the success rates of ankle fusions in the majority of cases. Well defined limitations and residual symptoms can be named on the basis of the available data.

Biomechanical dynamic comparison of biodegradable pins and titanium screws for operative stabilization of displaced radial head fractures.

For radial head osteosynthesis, biodegradable implants are gaining in importance to minimize cartilage destruction and implant impingement and to supersede implant removal. Since loss of reduction and pseudarthrosis remain challenging complications, new implants should at least provide comparable biomechanical properties as commonly used metal implants. The objective of this study was to compare the treatment by polylactide pins to titanium screws and to quantify the produced cartilage defects. Eight pairs of human cadaver radii with a standardized Mason type II fracture were stabilized either by two 2.0-mm polylactide pins or titanium screws. The produced cartilage defects were quantified using an image analyzing software. Quasi-static loading was performed axially and transversally for 10 cycles each between 10 and 50 N. Afterward, implant loosening was tested by axial loading up to 10,000 cycles, followed by load to failure testing. Polylactide pins showed less construct stiffness under axial (p = 0.017) and transversal (p = 0.012) loading, and one polylactide pins construct failed after two cycles of transversal loading. At axial loading, a high correlation between bone mineral density and construct stiffness was observed among polylactide pins (R = 0.667; p = 0.071), which was not seen among titanium screws (R = 0.262; p = 0.531). No difference in implant loosening was recorded after 10,000 cycles (p = 0.237); however, one polylactide pins construct failed after 30 cycles and failure loads were higher for titanium screws (p=0.017). Polylactide pin produced smaller cartilage defects (p=0.012). In conclusion, simple radial head fractures treated by polylactide pins show less biomechanical stability than treated by titanium screws, particularly in osteoporotic bone which might lead to secondary loss of reduction. Due to smaller cartilage defects and equal properties under continuous loading, polylactide pins might represent a gentle alternative in patients with good bone quality making subsequent implant removal redundant.

Improved clinical outcome after medial open-wedge osteotomy despite cartilage lesions in the lateral compartment.

High tibial medial open-wedge osteotomy (HTO) is an established treatment option for cartilage lesions in the medial compartment. It was this study's aim to evaluate the effect of asymptomatic single or kissing lesions in the lateral compartment on functional outcome after medial open-wedge osteotomy. A total of 156 patients were enrolled in this retrospective study. All patients underwent HTO due to a varus deformity and a symptomatic cartilage lesion or osteoarthritis in the medial compartment. We acquired preoperative Lysholm and VAS Scores. Each open-wedge osteotomy was preceded by diagnostic arthroscopy to ensure the compartments were thoroughly documented and diagnosed. Cartilage lesions in the lateral compartment were evaluated, and three groups created according to their individual characteristics: group A (no cartilage lesion, n = 119), group B (single cartilage lesion, n = 16) and group C (kissing lesions, n = 21). Cartilage lesions were graded according to the Outerbridge classification, The functional postoperative outcome was determined by relying on several parameters (VAS Score, Lysholm, KOOS, WOMAC Score). Pre- and postoperative long-leg axis views were analyzed via special planning software (mediCAD, Hectec GmbH Germany). Mean follow-up was at 69.0 ± 30.3 months after surgery (range 22 to 121 months). There were no significant differences between the three groups in the correction angle chosen (p = 0.16). Regarding the outcome parameters, group A attained the best results in the WOMACpain Score (p = 0.03) and WOMACfunction Score (p = 0.05). A higher Outerbridge-Score of cartilage lesions in the lateral compartment was associated with a higher (i.e., worse) WOMACpain Score (p = 0.018) and WOMACfunction Score (p = 0.033). In all the groups (A, B, and C), HTO led to a significant improvement in the Lysholm Score (p < 0.001) and to a decrease in pain level (VAS Score; p < 0.001). Conclusion: Valgus high tibial osteotomy leads to reduced pain and improved functional outcome scores, even in patients with pre-existing asymptomatic single or corresponding cartilage lesions in the lateral compartment. In case of severe cartilage lesions in the lateral compartment, surgeons should consider that clinical outcome worsens depending on the Outerbridge Score.

Identifying Disparities in the Management of Hip Fractures Within Europe: A Comparison of 3 Health-Care Systems.

INTRODUCTION: This study investigates the management of hip fractures in a German maximum care hospital and compares these data to evidence-based standard and practice in 180 hospitals participating in the UK National Hip Fracture Database (NHFD) and 16 hospitals participating in the Irish Hip Fracture Database (IHFD). This is the first study directly comparing the management of hip fractures between 3 separate health-care systems within Europe. METHODS: Electronic medical data were collected retrospectively describing the care pathway of elderly patients with a hip fracture admitted to a large trauma unit in the south of Germany "University Hospital Freiburg" (UHF). The audit evaluated demographics, postoperative outcome, and the adherence to the 6 "Blue Book" standards of care. These data were directly compared with the data from the UK NHFD and the IHFD acquired from 180 and 16 hospitals, respectively. RESULTS: At 36 hours, 95.8% of patients had received surgery in UHF, compared to 71.5% in the NHFD and 58% of patients in the IHFD. The rate of in-hospital mortality was 4.7% compared to 7.1% in the NHFD and 5% in the IHFD. The mean average acute length of stay was 13.4 days compared to 16.4 days in the NHFD and 20 days in the IHFD. Reoperation rates are 3.3% compared to 1% in the NHFD and 1.1% in the IHFD; 50.5% of patients were discharged on bone protection medication, compared to 47% in the IHFD and 79.3% in the UK NHFD. DISCUSSION: Despite uniformly acknowledged evidence-based treatment guidelines, the management of hip fractures remains heterogeneous within Europe. CONCLUSION: These data show that different areas of the hip fracture care pathway in Germany, England, and Ireland, respectively, show room for improvement in light of the growing socioeconomic burden these countries are expected to face.

Anatomical Reconstruction of the Acromion Using an Autologous Iliac Crest Graft for Treatment of Recurrent Chondroblastoma: A Case Report.

CASE: A 38-year-old man presented with recurrent chondroblastoma of the acromion after primary curettage and bone grafting. The patient underwent revision surgery with resection of the acromion and reconstruction using an autologous iliac crest graft. He had regained normal shoulder function without recurrence at a follow-up of 17 months. CONCLUSIONS: This case demonstrates a rare location of chondroblastoma and successful anatomical and functional reconstruction. The described surgical procedure could be considered for large tumorous lesions of the acromion, for which curettage would be insufficient, and to preserve and reconstruct a functionally intact shoulder girdle.

Clinical mid- to long-term outcome after autologous chondrocyte implantation for patellar cartilage lesions and its correlation with the geometry of the femoral trochlea.

BACKGROUND: The aim was to investigate the clinical results after autologous chondrocyte implantation (ACI) at the patella in a mid- to long-term course, and whether trochlear dysplasia has an influence on the outcome. METHODS: Inclusion criteria were ACI for focal patella cartilage defects and preoperative magnetic resonance imaging (MRI). Patients with previous trochleoplasty or osteotomy have been excluded. Trochlea morphology was evaluated by sulcus depth, sulcus angle, lateral condyle index (LCI) and Dejour's classification for trochlea dysplasia. The clinical outcome was evaluated by a questionnaire including the Kujala- and IKDC-Scores. Survival of the ACI was analysed by the Kaplan-Meier method. A correlation analysis between morphologic parameters and clinical scores was performed. RESULTS: Seventy-eight patients (mean age 33.2 ±â€¯10.7 years) were included (mean follow-up 6.5 ±â€¯3.4 years). The mean sulcus depth was 5.0 ±â€¯1.6 mm (normal value ≥5 mm), the mean sulcus angle was 153.4 ±â€¯9.0° (normal value ≤145°) and the mean LCI was 84.9 ±â€¯7.5% (normal value ≥90%). Major trochlea dysplasia (grades B-D) was seen in 29 patients (36.7%). Five-year survival rate was 98%, satisfaction-rate was 78.9% and the mean clinical scores were 67.6 ±â€¯20.2 for the Kujala-Score and 64.7 ±â€¯20.2 for the IKDC-Score. A lower LCI showed significant correlation with a lower IKDC score (r = 0.25; p = 0.037). CONCLUSIONS: The present study reports an excellent survival rate and a good satisfaction rate in a mid- to long-term course after patella ACI. The clinical scores show a high variance and there is evidence that a pathologic trochlea correlates with inferior results.

Isolated revision meniscal repair - failure rates, clinical outcome, and patient satisfaction.

BACKGROUND: Failure of isolated primary meniscal repair must be expected in approximately 10-25% of cases. Patients requiring revision surgery may benefit from revision meniscal repair, however, the results of this procedure remain underreported. The purpose of this study was therefore to evaluate the outcome and failure rates of isolated revision meniscal repair in patients with re-tears or failed healing after previous meniscal repair in stable knee joints. METHODS: A chart review was performed to identify all patients undergoing revision meniscal repair between 08/2010 and 02/2016. Only patients without concomitant procedures, without ligamentous insufficiency, and a minimum follow-up of 24 months were included. The records of all patients were reviewed to collect patient demographics, injury patterns of the meniscus, and details about primary and revision surgery. Follow-up evaluation included failure rates, clinical outcome scores (Lysholm Score, KOOS Score), sporting activity (Tegner scale), and patient satisfaction. RESULTS: A total of 12 patients with a mean age of 22 ± 5 years were included. The mean time between primary repair and revision repair was 27 ± 21 months. Reasons for failed primary repairs were traumatic re-tears in 10 patients (83%) and failed healing in two patients (17%). The mean follow-up period after revision meniscal repair was 43 (± 23.4) months. Failure of revision meniscal repair occurred in 3 patients (25%). In two of these patients, successful re-revision repair was performed. At final follow-up, the mean Lysholm Score was 95.2 (± 4.2) with a range of 90-100, representing a good to excellent result in all patients. The final assessment of the KOOS subscores also showed good to excellent results. The mean Tegner scale was 6.8 ± 1.8, indicating a relatively high level of sports participation. Ten patients (83%) were either satisfied or very satisfied with the outcome. CONCLUSION: In patients with re-tears or failed healing after previous isolated meniscal repair, revision meniscal repair results in good to excellent knee function, high level of sports participation, and high patient satisfaction. The failure rate is slightly higher compared to isolated primary meniscal repair, but still acceptable. Therefore, revision meniscal repair is worthwhile in selected cases in order to save as much meniscal tissue as possible.

Modified Lemaire extra-articular stabilisation of the knee for the treatment of anterolateral instability combined with diffuse pigmented villonodular synovitis: a case report.

BACKGROUND: Diffuse pigmented villonodular synovitis (PVNS) of the knee is a rare proliferative joint disease associated with high recurrence rates following surgical treatment. Intra-articular joint instability in conjunction with PVNS implies complex reconstructive strategies due to the destructive nature of the disease. CASE PRESENTATION: Here, we present the case of a young patient with refractory PVNS and a chronic ipsilateral anterior cruciate ligament (ACL) rupture. Clinically, the patient presented with a grade 3 pivot shift phenomenon, indicating anterolateral rotational instability. Usually, PVNS implies a contraindication for ACL reconstruction due to the degenerative and pro-inflammatory joint microenvironment that is induced and maintained by PVNS. Therefore, we have performed a modified Lemaire extra-articular stabilization resulting in significant clinical improvement and subjective joint stability. In the latest follow-up examination at 12 months, the patient reported subjective joint stability and no swelling. In the clinical examination, the patient showed dynamic joint stability during walking. Additionally, the patient presented with grade 0 in pivot-shifting compared to the contralateral knee. The Lachman test exhibited no increased side-to-side difference and a firm endpoint. CONCLUSIONS: Extra-articular anterolateral stabilisation of the knee in patients having anterolateral knee instability combined with PVNS is a safe and efficient surgical treatment option yielding significant clinical improvement as well as subjective joint stability.

Pelvic fractures in severely injured children: Results from the TraumaRegister DGU.

Injuries in the pelvic region in children and adolescents are very rare and often associated with a high energy trauma. Aim of this prospective multicenter study was, by analyzing the data from the TraumaRegister Deutsche Gesellschaft für Unfallchirurgie (TR-DGU), to evaluate any correlation between the severity of pelvic fractures and resulting mortality in different age groups.These study findings are based on a large pool of data retrieved from the prospectively-setup pelvic trauma registry established by the German Trauma Society (DGU) and the German Section of the Association for Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF) International in 1991. The registry provides data on all patients suffering pelvic fractures within a 14-year time frame at any 1 of the 23 level 1 trauma centers contributing to the registry. The analysis covers 4 age groups ranging from 0 to 17 years, covering different factors regarding pelvic fractures and their treatment.We identified a total of 9684 patients including 1433 pelvic fractures in children aged ≤17 years. Those patients were divided into 4 subgroups according to the patients' age (groups A-D) and according to the fracture severity (group 1 =  Abbreviated Injury Scale (AIS) score pelvis ≤2, and group 2 = AIS pelvis ≥3). The mortality in group 1 was 8.8% with a RISC (Revised Injury Severity Score) II of 8.6%, standard mortality rate (SMR) of 1.02 and 7.2% in group 2 with an RISC II of 9.9% (SMR 0.73). In pelvic factures of Type A (Tile classification of pelvic fractures), an SMR of 0.76 was recorded, in Type B fractures the SMR was 0.65, and in Type C fractures 0.79. Severe pelvic injuries (AIS pelvis ≥2) were associated with a higher rate of whole body computer tomograph (CT) scans (1-5 years: 80%, 6-10 years 81.8%, 11-14 years 84.7%, and 15-17 years 85.6%). The rate of pelvic surgery rose with the pelvic injury's severity (AIS 2: 7.6%, AIS 3: 35%, AIS 4: 65.6%, AIS 5 61.5%). We observed higher rates of preclinical and initial clinical hypotension defined as Riva-Rocci (RR) <90 mmHG) as well as of preclinical fluid application in all age groups. The presence of a pelvic injury was associated with a higher rate of severe abdominal injuries with an AIS of ≥3 (25.1% vs. 14.6%) and of severe thorax injuries with an AIS≥3 (43.6% vs. 28.6%).We have been able to analyze an enormous number of pelvic fractures in children and adolescents including different age groups by relying on data from the TR-DGU. Mortality seems to be associated with the severity of the pelvic injury, but is lower than the RISC II score's prognosis.

Preoperative Assessment of Neural Elements in Lumbar Spinal Stenosis by Upright Magnetic Resonance Imaging: An Implication for Routine Practice?

Introduction Lumbar spinal stenosis (LSS) is a kinetic-dependent disease typically aggravating during spinal loading. To date, assessment of LSS is usually performed with magnetic resonance imaging (MRI). However, conventional supine MRI is associated with significant drawbacks as it does not truly reflect physiological loads, experienced by discoligamentous structures during erect posture. Consequently, supine MRI often fails to reveal the source of pain and/or disability caused by LSS. The present study sought to assess neural dimensions via MRI in supine, upright, and upright-hyperlordotic position in order to evaluate the impact of patient positioning on neural narrowing. Therefore, radiological measures such as neuroforaminal dimensions, central canal volume, sagittal listhesis, and lumbar lordosis at spinal level L4/5 were extracted and stratified according to patient posture. Materials and methods Overall, 10 subjects were enclosed in this experimental study. MRI was performed in three different positions: (1) 0° supine (SP), (2) 80° upright (UP), and (3) 80° upright + hyperlordotic (HY) posture. Upright MRI was conducted utilizing a 0.25T open-configuration scanner equipped with a rotatable examination bed allowing for true standing MRI. Radiographic outcome of upright MRI imaging was extracted and evaluated according to patient positioning. Results Upright MRI-based assessment of neural dimensions was successfully accomplished in all subjects. Overall, radiographic parameters revealed a significant decrease of neural dimensions from supine to upright position: Specifically, mean foraminal area decreased from SP to UP by 13.3% (P ≤ 0.05) as well as from SP to HY position by 21% (P ≤ 0.05). Supplementation of hyperlordosis did not result in additional narrowing of neural elements (P ≥ 0.05). Furthermore, central canal volume revealed a decrease of 7% at HY and 8% at UP compared to SP position (P ≥ 0.05). Assessment of lumbar lordosis yielded in a significant increase when assessed at HY (+22.1%) or UP (+8.7%) compared to SP (P ≤ 0.05). Conclusions Our data suggest that neuroforaminal dimensions assessed by conventional supine MRI are potentially overestimated in patients with LSS. Especially, in patients having occult disease not visualized on conventional imaging modalities, upright MRI allows for a precise, clinically relevant, and at the same time non-invasive evaluation of neural elements in LSS when neural decompression is considered.

Efficacy of Thoracolumbar Bracing in Spinal Immobilization: Precise Assessment of Gross, Intersegmental, and Segmental Spinal Motion Restriction by a 3D Kinematic System.

BACKGROUND: Various diseases of the spine are treated by immobilization via orthoses, although detailed evidence on the efficiency of orthotic bracing remains elusive. The present study sought to investigate the impact of 3 different orthoses on spinal immobilization using 3-dimensional (3D) kinematic measurements. METHODS: Twelve healthy volunteers performed different motion tasks, including trunk flexion/extension and bilateral trunk bending. Movements were performed under 4 different conditions: 1) without orthosis, 2) while wearing a 3-point hyperextension brace (HB), 3) while wearing a custom-made semirigid orthosis (SO), and 4) while wearing a custom-made rigid orthosis (RO). Spinal motion was analyzed using a 3D optical motion capture system assessing regional, intersegmental, and segmental range of motion (ROM). RESULTS: Assessment of spinal motion was successfully accomplished in all subjects. Overall, orthoses significantly reduced spinal motion compared with no bracing. RO caused the greatest restriction of regional, intersegmental, and segmental spinal motion among all orthoses. For flexion/extension, the mean percentage decreases between T3 and L5 in full active ROM with HB, SO, and RO compared with no orthosis were 38%/30%, 48%/47%, and 51%/55%, respectively (P ≤ 0.05). Lateral bending was impaired by 28%, 44%, and 70%, respectively (P ≤ 0.05). Assessment of lateral bending revealed greater immobilization by SO and RO compared with HB (P ≤ 0.05). CONCLUSIONS: The present 3D kinematic system allows for precise assessment of spinal motion. Custom-made orthoses cause superior restriction on gross spinal motion compared "off-the-shelf" orthoses. If orthotic bracing is indicated, design, comfort, and patient compliance need to be carefully considered to guarantee successful therapy.