The influence of biological DMARDs on aseptic arthroplasty loosening: a retrospective cohort study.

OBJECTIVE: To investigate whether biological DMARDs affect the risk of aseptic loosening after total hip/knee arthroplasty (THA/TKA) in patients with RA. METHODS: We retrospectively identified all patients suffering from RA who underwent THA/TKA at our academic centre between 2002 and 2015 and linked them with an existing prospective observational RA database at our institution. The risk of aseptic loosening was estimated using radiological signs of component loosening (RCL). A time-dependent Cox regression analysis was used to compare the risk of implant loosening between patients treated with traditional DMARDS and biological DMARDs, or alternately both over time. RESULTS: A total of 155 consecutive total joint arthroplasties (TJAs) (103 TKA vs 52 THA) was retrospectively included in the study. Mean age at implantation was 59 ± 13 years. Mean follow-up time was 69 ± 43 months. Overall, 48 (31%) TJAs showed signs of RCL, with 28 (27.2%) RCLs occurring after TKA compared with 20 after THA (38.5%). A significant difference regarding the incidence of RCL between the traditional DMARDs group (39 cases of RCL, 35%) and the biological DMARDs group (nine cases of RCL, 21%) (P = 0.026) was observed using the log-rank test. This was also true when using a time-dependent Cox regression with therapy as well as arthroplasty location (hip vs knee) as variables (P = 0.0447). CONCLUSION: Biological DMARDs may reduce the incidence of aseptic loosening after TJA in patients with RA compared with traditional DMARDs. This effect seems to be more pronounced after TKA than THA.

Thirty-Year Minimum Follow-Up Outcome of a Straight Cementless Rectangular Stem.

BACKGROUND: Meta-diaphyseal fixation of straight, tapered, uncemented stems has been proven to be very reliable for total hip arthroplasty in 10 to 20 years of follow-up studies. The aim of the study was to evaluate whether the implant survival as well as radiological and functional outcome have changed in patients with a minimum follow-up of 30 years. METHODS: From a total of 210 patients, who received a straight, rectangular, tapered cementless stem and a threaded cup, there were 37 total hip arthroplasties (33 patients) still available for follow-up after a minimum of 30 years. Patients were examined clinically and radiographically, and revision surgeries were recorded. RESULTS: There was a low rate of revisions of the femoral stem with a survival probability of 0.92 (confidence interval 0.85 to 0.96) at 30 years. Survival probability of the acetabular component decreased drastically with 0.45 (confidence interval 0.30 to 0.59). Radiographic analysis of the stem revealed radiolucencies in 73% (n = 16), but only in the proximal/metaphyseal part and none of the stems were radiographically loose. CONCLUSION: In this minimum 30-year follow-up study, a straight rectangular cementless implant continues to provide excellent implant survival and high patient satisfaction. However, survival rates of the whole total hip replacement system were reduced by a high revision rate due to wear-related problems.

Ultra-long-term results of the Chiari pelvic osteotomy in hip dysplasia patients: a minimum of thirty-five years follow-up.

PURPOSE: The Chiari pelvic osteotomy was the first surgical procedure to address hip dysplasia by changing the position of the acetabulum by medialization, thus creating a bony roof and improving biomechanical conditions. The aim of this retrospective cohort study was to report on the very long-term results of this technique. METHODS: Out of a consecutive series of 1536 hips, 504 in 405 patients were available for follow-up. The patients were assessed by physical and radiological examination. A Kaplan-Meier survival analysis with total hip arthroplasty as an endpoint was performed and stratified for age groups, pre-operative diagnosis, sex and osteoarthritis stage. RESULTS: The average follow-up was 36 ± 8.1 years (range, 35.2 to 54). The average pain level on the Visual Analogue Scale was 2.9 ± 2.6 (range 0 to 8.7). The average Harris Hip Score was 80.2 ± 17.4 (range 17.4 to 100). Correction of dysplasia was effective and remained stable over time. Osteoarthritis significantly increased over time with 53% Tönnis grade 3 at follow-up. The cumulative survivorship was 79.8% (95% confidence interval (CI), 76.1-83.2%) at 20 years, 57.1% (95% CI, 52.8-61.8%) at 30 years and 35% (95% CI, 30.3-40.3%) at 40 years. Young age, male sex and low osteoarthritis grade were positive prognostic factors. CONCLUSIONS: Although the Chiari pelvic osteotomy is considered a salvage procedure nowadays, it achieved excellent long-term results even in indications, which would be treated differently today. Young patients without osteoarthritis had the best outcome.

Effect of hot water maceration, rehydration, and soft tissue presence on 3D geometry of bone.

PURPOSE: In forensic medicine, maceration is often essential for examining bone surfaces, serving purposes such as identifying cut marks, making geometric measurements, and determining the victim's age. While hot water maceration removes soft tissue effectively, it is known to cause bone surface shrinkage. This raises the question of whether this effect is permanent or if it can be partially reversed through rehydration, considering the presence of soft tissue. METHODS: Computed tomography (CT) scans were conducted on the radii of 20 paired human anatomic forearm specimens. Subsequently, the radii were extracted, macerated in 60 °C water, CT-scanned in an air environment, rehydrated, re-implanted into the forearms, and CT-scanned again. RESULTS: Maceration resulted in a mean shrinkage of 0.12 mm on the outer bone surface. This shrinkage was nearly fully recoverable for the diaphysis after rehydration and accounting for soft tissue surrounding the bone. In contrast, the epiphysis showed permanent shrinkage, likely due to the loss of small bone fragments. Analysis of the inner bone surface indicated a smaller effect, but with significant standard deviations, especially for the epiphysis, possibly related to the less well-defined nature of the inner bone surface. CONCLUSION: The epiphyseal surface of hot water-macerated bone will, on average, be approximately 0.15 mm deflated and cannot retain the original surface. On the other hand, the diaphyseal surface is less affected and can be nearly completely restored after rehydration and accounting for soft tissue surrounding the bone.

Metabolic rewiring controlled by c-Fos governs cartilage integrity in osteoarthritis.

OBJECTIVES: The activator protein-1 (AP-1) transcription factor component c-Fos regulates chondrocyte proliferation and differentiation, but its involvement in osteoarthritis (OA) has not been functionally assessed. METHODS: c-Fos expression was evaluated by immunohistochemistry on articular cartilage sections from patients with OA and mice subjected to the destabilisation of the medial meniscus (DMM) model of OA. Cartilage-specific c-Fos knockout (c-FosΔCh) mice were generated by crossing c-fosfl/fl to Col2a1-CreERT mice. Articular cartilage was evaluated by histology, immunohistochemistry, RNA sequencing (RNA-seq), quantitative reverse transcription PCR (qRT-PCR) and in situ metabolic enzyme assays. The effect of dichloroacetic acid (DCA), an inhibitor of pyruvate dehydrogenase kinase (Pdk), was assessed in c-FosΔCh mice subjected to DMM. RESULTS: FOS-positive chondrocytes were increased in human and murine OA cartilage during disease progression. Compared with c-FosWT mice, c-FosΔCh mice exhibited exacerbated DMM-induced cartilage destruction. Chondrocytes lacking c-Fos proliferate less, have shorter collagen fibres and reduced cartilage matrix. Comparative RNA-seq revealed a prominent anaerobic glycolysis gene expression signature. Consistently decreased pyruvate dehydrogenase (Pdh) and elevated lactate dehydrogenase (Ldh) enzymatic activities were measured in situ, which are likely due to higher expression of hypoxia-inducible factor-1α, Ldha, and Pdk1 in chondrocytes. In vivo treatment of c-FosΔCh mice with DCA restored Pdh/Ldh activity, chondrocyte proliferation, collagen biosynthesis and decreased cartilage damage after DMM, thereby reverting the deleterious effects of c-Fos inactivation. CONCLUSIONS: c-Fos modulates cellular bioenergetics in chondrocytes by balancing pyruvate flux between anaerobic glycolysis and the tricarboxylic acid cycle in response to OA signals. We identify a novel metabolic adaptation of chondrocytes controlled by c-Fos-containing AP-1 dimers that could be therapeutically relevant.

Soft tissue tumor imaging in adults: European Society of Musculoskeletal Radiology-Guidelines 2023-overview, and primary local imaging: how and where?

OBJECTIVES: Early, accurate diagnosis is crucial for the prognosis of patients with soft tissue sarcomas. To this end, standardization of imaging algorithms, technical requirements, and reporting is therefore a prerequisite. Since the first European Society of Musculoskeletal Radiology (ESSR) consensus in 2015, technical achievements, further insights into specific entities, and the revised WHO-classification (2020) and AJCC staging system (2017) made an update necessary. The guidelines are intended to support radiologists in their decision-making and contribute to interdisciplinary tumor board discussions. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements were scored online by level of agreement (0 to 10) during two iterative rounds. Either "group consensus," "group agreement," or "lack of agreement" was achieved. RESULTS: Eight sections were defined that finally contained 145 statements with comments. Overall, group consensus was reached in 95.9%, and group agreement in 4.1%. This communication contains the first part consisting of the imaging algorithm for suspected soft tissue tumors, methods for local imaging, and the role of tumor centers. CONCLUSION: Ultrasound represents the initial triage imaging modality for accessible and small tumors. MRI is the modality of choice for the characterization and local staging of most soft tissue tumors. CT is indicated in special situations. In suspicious or likely malignant tumors, a specialist tumor center should be contacted for referral or teleradiologic second opinion. This should be done before performing a biopsy, without exception. CLINICAL RELEVANCE: The updated ESSR soft tissue tumor imaging guidelines aim to provide best practice expert consensus for standardized imaging, to support radiologists in their decision-making, and to improve examination comparability both in individual patients and in future studies on individualized strategies. KEY POINTS: • Ultrasound remains the best initial triage imaging modality for accessible and small suspected soft tissue tumors. • MRI is the modality of choice for the characterization and local staging of soft tissue tumors in most cases; CT is indicated in special situations. Suspicious or likely malignant tumors should undergo biopsy. • In patients with large, indeterminate or suspicious tumors, a tumor reference center should be contacted for referral or teleradiologic second opinion; this must be done before a biopsy.

Early postoperative gain in activity levels of lower extremity sarcoma survivors positively affects long-term physical activity and performance.

PURPOSE: Little is known about the effect of sports activity levels on health-related quality of life (HRQOL) in long-term survivors of lower-extremity sarcoma. METHODS: Eighty-three long-term survivors of bone and soft tissue sarcoma of the lower extremities with a median follow-up of 14 (range: 5-35) years completed the University of California and Los Angeles (UCLA) activity scores before tumor resection, 1 year after surgery and at the latest follow-up, as well as a Short Form 36 (SF-36) health survey at the latest follow-up. Simple linear regression models as well as stepwise variable selection with Akaike information criterion (AIC) were undertaken. RESULTS: The preoperative UCLA activity level (median: 9, range: 2-10) dropped to a median of 4 (range: 1-10) 1 year after surgery before increasing to a score of 6 (range: 2-10) 5 years after surgery. The long-term SF-36 physical health component summary score (PCS) was 49 (SD: 9), and the mental health component summary score (MCS) was 54 (SD: 7). A linear model with stepwise variable selection identified a negative correlation of PCS with age at surgery (estimate: -0.2; p = 0.02), UCLA score at the last follow-up (estimate: 1.4; p = 0.02) and UCLA score 1 year after surgery (estimate: 1.0; p = 0.02). CONCLUSION: As not only the final activity levels but also the status immediately after surgery affect the PCS, higher early activity levels should be a goal of modern rehabilitation after sarcoma treatment. Further studies are needed to weigh the potential postoperative risks of higher sport activity levels against the benefits described in this study. LEVEL OF EVIDENCE: Level 4.

Activation of the Mechanosensitive Ion Channels Piezo1 and TRPV4 in Primary Human Healthy and Osteoarthritic Chondrocytes Exhibits Ion Channel Crosstalk and Modulates Gene Expression.

Osteoarthritis (OA) is the most common degenerative joint disease causing pain and functional limitations. Physical activity as a clinically relevant, effective intervention alleviates pain and promotes joint function. In chondrocytes, perception and transmission of mechanical signals are controlled by mechanosensitive ion channels, whose dysfunction in OA chondrocytes is leading to disease progression. Signaling of mechanosensitive ion channels Piezo/TRPV4 was analyzed by Yoda1/GSK1016790A application and calcium-imaging of Fura-2-loaded chondrocytes. Expression analysis was determined by qPCR and immunofluorescence in healthy vs. OA chondrocytes. Chondrocytes were mechanically stimulated using the Flexcell™ technique. Yoda1 and GSK1016790A caused an increase in intracellular calcium [Ca2+]i for Yoda1, depending on extracellularly available Ca2+. When used concomitantly, the agonist applied first inhibited the effect of subsequent agonist application, indicating mutual interference between Piezo/TRPV4. Yoda1 increased the expression of metalloproteinases, bone-morphogenic protein, and interleukins in healthy and OA chondrocytes to a different extent. Flexcell™-induced changes in the expression of MMPs and ILs differed from changes induced by Yoda1. We conclude that Piezo1/TRPV4 communicate with each other, an interference that may be impaired in OA chondrocytes. It is important to consider that mechanical stimulation may have different effects on OA depending on its intensity.

Distal locking technique affects the rate of iatrogenic radial nerve palsy in intramedullary nailing of humeral shaft fractures.

BACKGROUND: Intramedullary humeral nailing is a common and reliable procedure for the treatment of humeral shaft fractures. Radial nerve palsy is a common complication encountered in the treatment of this pathology. The radial nerve runs from posterior to anterior at the lateral aspect of the distal humerus. Hence, there is reason to believe that due to the anatomic vicinity of the radial nerve in this area, lateral-medial distal locking in intramedullary nailing of the humerus may be associated with a greater risk for iatrogenic radial nerve injury compared to anterior-posterior locking. QUESTIONS/PURPOSE: To assess whether the choice of distal locking (lateral-medial versus anterior-posterior distal locking) in intramedullary humeral nailing of humeral shaft fractures affects the risk for iatrogenic radial nerve injury. PATIENTS AND METHODS: Overall, 203 patients (116 females, mean age 64.3 ± 18.6 years), who underwent intramedullary nailing of the humerus between 2000 and 2020 at a single level-one trauma center, met the inclusion criteria and were analyzed in this retrospective case-control study. Patients were subdivided into two groups according to the distal locking technique. RESULTS: Anterior-posterior locking was performed in 176 patients versus lateral-medial locking in 27 patients. We observed four patients with iatrogenic radial nerve palsy in both groups. Risk for iatrogenic radial nerve palsy was almost 7.5 times higher for lateral-medial locking (OR 7.48, p = 0.006). There was no statistically significant difference regarding intraoperative complications, union rates or revision surgeries between both groups. CONCLUSIONS: Lateral-medial distal locking in intramedullary nailing of the humerus may be associated with a greater risk for iatrogenic radial nerve palsy than anterior-posterior locking. Hence, we advocate for anterior-posterior locking. LEVEL OF EVIDENCE: Level III retrospective comparative study.

Patient-Specific Guides for Accurate and Precise Positioning of Osseointegrated Implants in Transfemoral Amputations: A Proof-of-Concept In Vitro Study.

Background and Objectives: The treatment of transfemoral amputees using osseointegrated implants for prosthetic anchorage requires accurate implant positioning when using threaded bone-anchoring implants due to the curvature of the femur and the risk of cortical penetration in misaligned implants. This study investigated the accuracy and precision in implant positioning using additively manufactured case-specific positioning guides. Materials and Methods: The geometry and density distribution of twenty anatomic specimens of human femora were assessed in quantitative computed tomography (QCT) scanning. The imaging series were used to create digital 3D specimen models, preoperatively plan the optimal implant position and manufacture specimen-specific positioning guides. Following the surgical bone preparation and insertion of the fixture (threaded bone-anchoring element) (OPRA; Integrum AB, Mölndal, Sweden), a second QCT imaging series and 3D model design were conducted to assess the operatively achieved implant position. The 3D models were registered and the deviations of the intraoperatively achieved implant position from the preoperatively planned implant position were analyzed as follows. The achieved, compared to the planned implant position, was presented as resulting mean hip abduction or adduction (A/A) and extension or flexion (E/F) and mean implant axis offset in medial or lateral (M/L) and anterior or posterior (A/P) direction measured at the most distal implant axis point. Results: The achieved implant position deviated from the preoperative plan by 0.33 ± 0.33° (A/A) and 0.68 ± 0.66° (E/F) and 0.62 ± 0.55 mm (M/L) and 0.68 ± 0.56 mm (A/P), respectively. Conclusions: Using case-specific guides, it was feasible to achieve not only accurate but also precise positioning of the implants compared to the preoperative plan. Thus, their design and application in the clinical routine should be considered, especially in absence of viable alternatives.

Human repair-related Schwann cells adopt functions of antigen-presenting cells in vitro.

The plastic potential of Schwann cells (SCs) is increasingly recognized to play a role after nerve injury and in diseases of the peripheral nervous system. Reports on the interaction between immune cells and SCs indicate their involvement in inflammatory processes. However, the immunocompetence of human SCs has been primarily deduced from neuropathies, but whether after nerve injury SCs directly regulate an adaptive immune response is unknown. Here, we performed comprehensive analysis of immunomodulatory capacities of human repair-related SCs (hrSCs), which recapitulate SC response to nerve injury in vitro. We used our well-established culture model of primary hrSCs from human peripheral nerves and analyzed the transcriptome, secretome, and cell surface proteins for pathways and markers relevant in innate and adaptive immunity, performed phagocytosis assays, and monitored T-cell subset activation in allogeneic co-cultures. Our findings show that hrSCs are phagocytic, which is in line with high MHCII expression. Furthermore, hrSCs express co-regulatory proteins, such as CD40, CD80, B7H3, CD58, CD86, and HVEM, release a plethora of chemoattractants, matrix remodeling proteins and pro- as well as anti-inflammatory cytokines, and upregulate the T-cell inhibiting PD-L1 molecule upon pro-inflammatory stimulation with IFNγ. In contrast to monocytes, hrSC alone are not sufficient to trigger allogenic CD4+ and CD8+ T-cells, but limit number and activation status of exogenously activated T-cells. This study demonstrates that hrSCs possess features and functions typical for professional antigen-presenting cells in vitro, and suggest a new role of these cells as negative regulators of T-cell immunity during nerve regeneration.

Galectin network in osteoarthritis: galectin-4 programs a pathogenic signature of gene and effector expression in human chondrocytes in vitro.

Galectin-4 (Gal-4) is a member of the galectin family, which have been identified as galactose-binding proteins. Gal-4 possesses two tandem repeat carbohydrate recognition domains and acts as a cross-linking bridge in sulfatide-dependent glycoprotein routing. We herein document its upregulation in osteoarthritis (OA) in correlation with the extent of cartilage degradation in vivo. Primary human OA chondrocytes in vitro respond to carbohydrate-inhibitable Gal-4 binding with the upregulation of pro-degradative/-inflammatory proteins such as interleukin-1ß (IL-1ß) and matrix metalloproteinase-13 (MMP-13), as documented by RT-qPCR-based mRNA profiling and transcriptome data processing. Activation of p65 by phosphorylation of Ser536 within the NF-κB pathway and the effect of three p65 inhibitors on Gal-4 activity support downstream involvement of such signaling. In 3D (pellet) cultures, Gal-4 presence causes morphological and biochemical signs of degradation. Taken together, our findings strongly support the concept of galectins acting as a network in OA pathogenesis and suggest that blocking their activity in disease progression may become clinically relevant in the future.

Transverse Relaxation Anisotropy of the Achilles and Patellar Tendon Studied by MR Microscopy.

BACKGROUND: T2 * anisotropy affects the clinical assessment of tendons (magic-angle artifact) and may be a source of T2 *-misinterpretation. PURPOSE: To analyze T2 *-anisotropy and T2 *-decay of Achilles and patellar tendons in vitro at microscopic resolution using a variable-echo-time (vTE) sequence. STUDY TYPE: Prospective. SPECIMEN: Four human Achilles and four patellar tendons. FIELD STRENGTH/SEQUENCE: A 7 T MR-microscopy; 3D-vTE spoiled-gradient-echo-sequence (T2 *-mapping). ASSESSMENT: All tendons were measured at 0° and 55° relative to B0 . Additional angles were measured for one Achilles and one patellar tendon for a total of 11 angles ranging from 0° to 90°. T2 *-decay was analyzed with mono- and bi-exponential signal fitting. Mono-exponential T2 *-values (T2 *m ), short and long T2 *-components (T2 *s , T2 *l ), and the fraction of the short component Fs of the bi-exponential T2 *-fit were calculated. T2 *-decay characteristics were compared with morphological MRI and histologic findings based on a region-of-interest analysis. STATISTICAL TESTS: Akaike information criterion (AICC ), F-test, and paired t-test. A P value smaller than the α-level of 0.05 was considered statistically significant. RESULTS: T2 *m -values between fiber-to-field angles of 0° and 55° were increased on average from T2 *m (0°) = 1.92 msec to T2 *m (55°) = 29.86 msec (15.5-fold) in the Achilles and T2 *m (0°) = 1.46 msec to T2 *m (55°) = 23.33 msec (16.0-fold) in the patellar tendons. The changes in T2 *m -values were statistically significant. For the whole tendon, according to F-test and AICC , a bi-exponential model was preferred for angles close to 0°, while the mono-exponential model tended to be preferred at angles close to 55°. CONCLUSION: MR-microscopy provides a deeper insight into the relationship between T2 *-decay (mono- vs. bi-exponential model) and tendon heterogeneity. Changes in fiber-to-field angle result in significant changes in T2 *-values. Thus, we conclude that awareness of T2 *-anisotropy should be noted in quantitative T2 *-mapping of tendons to avoid T2 *-misinterpretation such as a false positive detection of degeneration due to large fiber-to-field angles. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

Targeting osteoarthritis-associated galectins and an induced effector class by a ditopic bifunctional reagent: Impact of its glycan part on binding measured in the tissue context.

Pairing glycans with tissue lectins controls multiple effector pathways in (patho)physiology. A clinically relevant example is the prodegradative activity of galectins-1 and -3 (Gal-1 and -3) in the progression of osteoarthritis (OA) via matrix metalloproteinases (MMPs), especially MMP-13. The design of heterobifunctional inhibitors that can block galectin binding and MMPs both directly and by preventing their galectin-dependent induction selectively offers a perspective to dissect the roles of lectins and proteolytic enzymes. We describe the synthesis of such a reagent with a bivalent galectin ligand connected to an MMP inhibitor and of two tetravalent glycoclusters with a subtle change in headgroup presentation for further elucidation of influence on ligand binding. Testing was performed on clinical material with mixtures of galectins as occurring in vivo, using sections of fixed tissue. Two-colour fluorescence microscopy monitored binding to the cellular glycome after optimization of experimental parameters. In the presence of the inhibitor, galectin binding to OA specimens was significantly reduced. These results open the perspective to examine the inhibitory capacity of custom-made ditopic compounds on binding of lectins in mixtures using sections of clinical material with known impact of galectins and MMPs on disease progression.

Treatment of benign bone lesions with an injectable biphasic bone substitute.

BACKGROUND: Injectable biphasic ceramic bone substitutes (BCBSs) represent a modern alternative to conventional options for bone defect filling, as they further open the possibilities for percutaneous cavity reconstruction. Although recent studies have shown good surgical outcomes after treatment with BCBSs, mid-term follow-up data are still missing. PATIENTS AND METHODS: Between 2013 and 2017, 18 patients were [1] treated with BCBS [2] for benign bone lesions and [3] had a complete set of retrospective information, including surgical protocols, imaging, patient dismission letters and outpatient clinic protocols, [4] with a minimum follow-up time of one year. Eleven patients received percutaneous surgery, while 7 patients had open curettage and BCBS filling. The median follow-up time was 36.5 (range 12-80) months. RESULTS: Local recurrence was reported in four patients. A distinctive bone remodelling pattern was noted on follow-up X-ray and magnetic resonance imaging showing a double-line phenomenon and continuously increasing cortical thickness one year after treatment in nine of thirteen patients. Regarding surgical complications, one patient suffered from a septic complication that required BCBS removal and lavage. One patient experienced superficial surgical site inflammation with redness and swelling, while two other patients had prolonged wound secretion. CONCLUSION: In a limited case series, the studied BCBS demonstrated acceptable surgical outcomes. Initial wound leakage and recurrence seemed to be associated with percutaneous injection. Further studies are needed to compare recurrence and bone graft resorption after open and percutaneous bone cyst surgeries and to further evaluate postoperative surgical site inflammation, which appears self-limiting in most cases.

Nineteen percent of meniscus repairs are being revised and failures frequently occur after the second postoperative year: a systematic review and meta-analysis with a minimum follow-up of 5 years.

PURPOSE: Meniscus repair has gained increasing interest over the last two decades as loss of meniscus tissue predisposes to early onset knee arthritis. Although there are many reports of meniscus repair outcome in short-term studies, data on the long-term outcome of meniscus repair are still scarce. The purpose of this meta-analysis was to evaluate the overall failure rate of meniscus repair with a minimum follow-up of 5 years. Additionally, possible factors influencing meniscus repair outcome were assessed. METHODS: PubMed and Scopus were searched for studies of the last 20 years reporting on meniscus repair outcome with a minimum follow-up of 5 years. The study was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search terms used for this study were ([meniscus OR meniscal] AND repair). Titles and abstracts were evaluated by two authors independently. Using meta package of R (version 3.6.2), random-effect models were performed to pool failure rates. Subgroup analyses were performed and effect estimates in form of an odds ratio with 95% CIs were established. RESULTS: In total, 12 studies with 864 patients were included. Degenerative tears were excluded in two studies and one study only included traumatic meniscus tears. Other studies did not state whether the cause of meniscus tear was degenerative or traumatic. Studies reporting meniscus repair outcome on root repairs, revision anterior cruciate ligament reconstruction, discoid menisci or ramp lesions were excluded. Revision surgery was used as failure definition in all included studies. The overall failure rate of meniscal repair at a mean follow-up of 86 months was 19.1%. There was no significant difference in meniscus repair outcome when performed in combination with anterior cruciate ligament reconstruction compared to isolated meniscus repair (18.7% vs. 28%; n.s.) or when performed on the lateral meniscus compared to the medial meniscus (19.5% vs. 24.4%; n.s.). There was no significant difference of meniscus repair outcome between vertical/longitudinal tears and bucket-handle tears (n.s.). Thirty-six percent of meniscus repair failures occur after the second postoperative year. The only significant finding was that inside-out repair results in a lower failure rate compared to all-inside repair (5.6% vs. 22.3%; p = 0.009) at 5 years. CONCLUSION: The overall meniscus repair failure rate remains nineteen percent in long-term studies. The cause of failure is poorly documented, and it remains unclear whether failure of the meniscus repair itself or additional adjacent tears lead to revision surgery. Despite the given technical advantages of all-inside repair devices, this meta-analysis cannot demonstrate superior outcomes compared to inside-out or outside-in repair at 5 years. LEVEL OF EVIDENCE: IV.

The top fifty most influential articles on hip fractures.

PURPOSE: Hip fractures are one of the most common disabling fractures in elderly people and peri-operative management has advanced considerably over the past decades. The purpose of this study was to evaluate the change of scientific focus by creating a top 50 list of the most influential papers on this topic. METHODS: The Clarivate Web of Science Search was used to identify the most cited articles. The used search phrase was [(hip OR pertrochanteric OR (femoral neck)) AND fracture AND (surgery OR treatment)]. The number of citations, citation density, study type, study design, published year, fracture type, country, evidence level and published journal were recorded. RESULTS: The top 50 articles were published between 1973 and 2014 and cited between 88 and 496 times. The mean citation density increased noticeably after the year 2000, representing the knowledge gain of the last 20 years. The topics surgical treatment (n = 19), risk factor assessment (n = 19), perioperative hemodynamic management (n = 7), additional treatment (n = 4) and general reviews (n = 1) were covered. Twenty-five articles were published from institutions in Europe, 24 from institutions in North America and one from an institution in Asia. CONCLUSION: While studies about surgical treatment options and risk factor assessment have been historically important, there was a rise of articles about additional treatment options for osteoporosis and the optimal postoperative care after the year 2005. The presented lists and map of citation classics give an overview of the most influential studies on hip fractures.

Biomechanical evaluation of the proximal chevron osteotomy in comparison to the Lapidus arthrodesis for the correction of hallux valgus deformities.

PURPOSE: The proximal chevron osteotomy and the modified Lapidus arthrodesis are both procedures utilized for deformity correction in patients with severe symptomatic hallux valgus. The aim of the current study was to compare their biomechanical stability when using locking plate fixation. METHODS: Twelve matched pairs of human anatomical lower leg specimens underwent on one side a proximal chevron osteotomy with a medial locking plate and on the other side a modified Lapidus arthrodesis with a plantar locking plate utilizing an interfragmentary compression screw. All specimens underwent bone mineral density (BMD) assessment and were tested in a servohydraulic load frame which applied a load on the centre of the metatarsal head over 1000 loading cycles with subsequently ultimate load testing. Displacement of the proximal and distal bone segment, ultimate load, and bending stiffness were analyzed. RESULTS: Mean displacement of both procedures showed no statistically significant difference throughout all the loading cycles (0.213 ≤ p ≤ 0.834). The mean ultimate load of the proximal chevron osteotomy was 227.9 N (± 232.4) and of the modified Lapidus arthrodesis 162.9 N (± 74.6) (p = 0.754). The proximal chevron osteotomy (38.2 N/mm (± 24.9)) had a significantly higher bending stiffness compared to the modified Lapidus arthrodesis (17.3 N/mm (± 9.9)) (p = 0.009). There was no correlation between BMD and displacement in all loading cycles, ultimate load, and bending stiffness of either procedure (p > 0.05). CONCLUSION: Although the bending stiffness of the chevron osteotomy was higher, there was no statistically significant difference between the surgical techniques in mean displacement and ultimate load. The BMD did not influence the overall stability of either reconstruction. Locking plate fixation increases the clinical value of the modified Lapidus arthrodesis by outweighing most of the biomechanical disadvantages in comparison to the proximal chevron osteotomy.

Specific knowledge and resilience affect short-term outcome in patients following primary total hip arthroplasty.

PURPOSE: The aim of the present study was to investigate the potential associations between specific knowledge, resilience and patient-reported outcome measures (PROMS) following primary total hip arthroplasty (THA). METHODS: In a cross-sectional prospective study, consecutive patients following primary THA were included at a rehabilitation center. A novel knowledge score and the validated Connor Davidson Resilience Scale (CD-RISC) were utilized to assess patients' specific knowledge and resilience, respectively. Additionally, patients completed a qualitative questionnaire regarding the information they had received. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as the University of California and Los Angeles Score (UCLA) served as primary outcome measures. Stepwise multiple regression analysis was performed to identify potential predictors of outcome. RESULTS: A total of 103 patients at a mean age of 67.5 years (SD 10.5, 38-88) were included in the analysis at a median of 55.5 days (IQR 43-81) following primary THA. The mean knowledge and resilience scores were 3.8 (SD 1.6, 0-7) and 69.5 (SD 18.5, 0-100), respectively. Forty-seven percent of patients were afraid of harming their prosthesis and these patients had up to 59% worse WOMAC scores (p < 0.001). WOMAC scores on admission to rehabilitation were predicted by resilience and knowledge scores (R2 = 0.106, p = 0.036). UCLA scores at the time of admission were predicted by knowledge scores (R2 = 0.078, p = 0.007). CONCLUSION: The present study demonstrated that patients with a feeling of uncertainty had an inferior short-term functional outcome following primary THA. Moreover, it could be shown that higher specific knowledge and resilience are associated with a better functional outcome according to validated PROMS. While these findings need to be prospectively validated in future studies, specific patient knowledge and resilience may have a direct impact on the outcome of primary THA.

[Femoroacetabular impingement syndrome in adolescents-How to adivse? How to treat?] / Femoroazetabuläres Impingement-Syndrom bei Adoleszenten ­ Wie beraten? Wie behandeln?

BACKGROUND: Femoroacetabular impingement syndrome (FAIS) is a relevant cause of groin pain in adolescents. Athletes are particularly affected. OBJECTIVES: The article shall provide an evidence-based background for FAIS counseling and therapy in adolescents. MATERIAL AND METHODS: On the basis of the current literature, an overview of the prevalence and pathogenesis, evaluation and diagnostics, as well as the therapeutic recommendations for FAIS in adolescents was compiled. RESULTS AND DISCUSSION: FAIS in adolescents primarily affects physically active patients. Certain sports favor the development of FAIS. Cam impingement, pincer impingement, and combined FAIS are the most common entities in this age group. Cam morphology occurs shortly before closure of the proximal femoral growth plate. In cam impingement, the slipped capital femoral epiphysis (SCFE) must be distinguished from the primary cam morphology. SCFE requires rapid surgical treatment with stabilization of the epiphysis, while primary cam impingement can be analyzed electively, and conservative treatment is first recommended. Damage to the labrum and cartilage is regularly observed. A systematic radiological evaluation using X­rays and MRI is mandatory in order to develop an adequate treatment plan. In adolescent patients with FAIS, a conservative attempt at therapy should always be made; if this is unsuccessful, surgical repair with hip arthroscopy is indicated. The postoperative results are very good in adolescents, with a rapid improvement in symptoms, few complications, and a high return-to-sport rate.