The Outcomes of Hip and Knee Fungal Periprosthetic Joint Infections: A Retrospective Cohort Study.

BACKGROUND: Fungal infections are a rare cause of periprosthetic joint infection (PJI), identified in 1% of all of these cases. Outcomes are not well-established due to small cohort sizes in the published literature. The aims of this study were to establish the patient demographics and infection-free survival of patients presenting to 2 high-volume revision arthroplasty centers who had fungal infection of either a hip or knee arthroplasty. We sought to identify risk factors for poor outcomes. METHODS: A retrospective analysis was performed of patients at 2 high-volume revision arthroplasty centers who had confirmed fungal PJI of the total hip arthroplasty (THA) and total knee arthroplasty (TKA). Consecutive patients treated between 2010 and 2019 were included. Patient outcomes were classified as infection eradication or persistence. A total of 67 patients who had 69 fungal PJI cases were identified. There were 47 cases involving the knee and 22 of the hip. Mean age at presentation was 68 years (THA mean 67, range 46 to 86) (TKA mean 69, range, 45 to 88). A history of sinus or open wound was present in 60 cases (89%) (THA 21 cases, TKA 39 cases). The median number of operations prior to the procedure at which fungal PJI was identified was 4 (range, 0 to 9), THA 5 (range, 3 to 9), and TKA 3 (range, 0 to 9). RESULTS: At a mean follow-up 34 months (range, 2 to 121), remission rates were 11 of 24 (45%) and 22 of 45 (49%) for hip and knee, respectively. There were 7 TKA (16%) and 1 THA cases (4%) that failed treatment resulting in amputations. During the study period, 7 THA and 6 TKA patients had died. Two deaths were directly attributable to PJI. Patient outcome was not associated with the number of prior procedures, patient comorbidities, or organisms. CONCLUSION: Eradication of fungal PJI is achieved in less than half of patients, and outcomes are comparable for TKA and THA. The majority of patients who have fungal PJI present with an open wound or sinus. No factors were identified that increase the risk of persistent infection. Patients who have fungal PJI should be informed of the poor outcomes.

Midkine Interaction with Chondroitin Sulfate Model Synthetic Tetrasaccharides and Their Mimetics: The Role of Aromatic Interactions.

Midkine (MK) is a neurotrophic factor that participates in the embryonic central nervous system (CNS) development and neural stem cell regulation, interacting with sulfated glycosaminoglycans (GAGs). Chondroitin sulfate (CS) is the natural ligand in the CNS. In this work, we describe the interactions between a library of synthetic models of CS-types and mimics. We did a structural study of this library by NMR and MD (Molecular Dynamics), concluding that the basic shape is controlled by similar geometry of the glycosidic linkages. Their 3D structures are a helix with four residues per turn, almost linear. We have studied the tetrasaccharide-midkine complexes by ligand observed NMR techniques and concluded that the shape of the ligands does not change upon binding. The ligand orientation into the complex is very variable. It is placed inside the central cavity of MK formed by the two structured beta-sheets domains linked by an intrinsically disordered region (IDR). Docking analysis confirmed the participation of aromatics residues from MK completed with electrostatic interactions. Finally, we test the biological activity by increasing the MK expression using CS tetrasaccharides and their capacity in enhancing the growth stimulation effect of MK in NIH3T3 cells.

Clinical Outcome of Free Latissimus Dorsi Flaps for Coverage of Soft Tissue Defects in Multiply Revised Total Knee Arthroplasties.

BACKGROUND: Multiply revised total knee arthroplasties (TKAs) may present with large anterior soft tissue defects, which can be challenging to reconstruct. In the rare cases where local flaps are insufficient, we use free latissimus dorsi (LD) myocutaneous flaps to achieve soft tissue coverage. This study looked to determine implant survivorship, infection status, and patient-reported outcomes of patients undergoing simultaneous revision TKA and LD flaps in a tertiary unit. METHODS: This was a retrospective study of 18 consecutive patients who had revision TKA and free LD flap reconstruction. Twelve were male and the median age was 65 years (range, 35-83). Patients had undergone a median of 4 previous arthroplasty procedures (range, 3-6). Median follow-up was 49 months (range, 18 to 110). The primary outcome was revision-free implant survival. Secondary outcomes included soft tissue integrity, Oxford Knee Score, and EuroQol 5-domain score at latest follow-up. RESULTS: At latest follow-up, 14 of 18 patients had maintained their implant. Seven patients were infection-free, 7 were on suppressive antibiotics with the implant in situ, and 4 had undergone above-knee amputation. Five-year implant survival was 75% (95% confidence interval, 46-90). At median follow-up (49 months), mean Oxford Knee Score was 13.4 (range, 2-35) and mean EuroQol 5-domain index was 0.071 (range:-0.427 to 0.747). CONCLUSION: LD free flap is a viable option for limb salvage in patients with large anterior soft tissue defects following multiple revisions of TKA. However, functional outcomes can be poor and there is a significant risk of ongoing infection and amputation in this complex patient cohort.

Gait assessment as a functional outcome measure in total knee arthroplasty: a cross-sectional study.

BACKGROUND: The aim of the study was to assess gait in total knee arthroplasty (TKA) patients, using a technique that can to be used on a routine basis in a busy orthopaedic clinic. METHODS: A total of 103 subjects were recruited: 29 pre-op TKA patients; 17 TKA patients at 8 weeks post-op; 28 TKA patients at 52 weeks post-op; and 29 age-matched controls. Inertial measurement units (IMUs) were used to assess gait. Limb segment angles, knee angle and temporal parameters of gait were calculated. Specific gait parameters were quantified, and data analysed using MANOVA and discriminant analysis. RESULTS: The gait of TKA patients as a group was only slightly improved at 12 months when compared with the pre-operative group, and both groups were significantly different to controls in several variables. Knee flexion range in stance was the most important variable in discriminating between patients and controls; knee flexion range in swing was the only variable that showed a significant difference between pre- and post-operative patients. When considered individually, only 1/29 patient was within the normal range for this variable pre-operatively, but 9/28 patients were within the normal range 12 months post-operatively. CONCLUSIONS: Even after 12 months after surgery, many TKA patients have not improved their gait relative to pre-operative patients. Routine gait assessment may be used to guide post-operative rehabilitation, and to develop strategies to improve mobility of these patients.

Effect of Opioids vs NSAIDs and Larger vs Smaller Chest Tube Size on Pain Control and Pleurodesis Efficacy Among Patients With Malignant Pleural Effusion: The TIME1 Randomized Clinical Trial.

IMPORTANCE: For treatment of malignant pleural effusion, nonsteroidal anti-inflammatory drugs (NSAIDs) are avoided because they may reduce pleurodesis efficacy. Smaller chest tubes may be less painful than larger tubes, but efficacy in pleurodesis has not been proven. OBJECTIVE: To assess the effect of chest tube size and analgesia (NSAIDs vs opiates) on pain and clinical efficacy related to pleurodesis in patients with malignant pleural effusion. DESIGN, SETTING, AND PARTICIPANTS: A 2×2 factorial phase 3 randomized clinical trial among 320 patients requiring pleurodesis in 16 UK hospitals from 2007 to 2013. INTERVENTIONS: Patients undergoing thoracoscopy (n = 206; clinical decision if biopsy was required) received a 24F chest tube and were randomized to receive opiates (n = 103) vs NSAIDs (n = 103), and those not undergoing thoracoscopy (n = 114) were randomized to 1 of 4 groups (24F chest tube and opioids [n = 28]; 24F chest tube and NSAIDs [n = 29]; 12F chest tube and opioids [n = 29]; or 12F chest tube and NSAIDs [n = 28]). MAIN OUTCOMES AND MEASURES: Pain while chest tube was in place (0- to 100-mm visual analog scale [VAS] 4 times/d; superiority comparison) and pleurodesis efficacy at 3 months (failure defined as need for further pleural intervention; noninferiority comparison; margin, 15%). RESULTS: Pain scores in the opiate group (n = 150) vs the NSAID group (n = 144) were not significantly different (mean VAS score, 23.8 mm vs 22.1 mm; adjusted difference, -1.5 mm; 95% CI, -5.0 to 2.0 mm; P = .40), but the NSAID group required more rescue analgesia (26.3% vs 38.1%; rate ratio, 2.1; 95% CI, 1.3-3.4; P = .003). Pleurodesis failure occurred in 30 patients (20%) in the opiate group and 33 (23%) in the NSAID group, meeting criteria for noninferiority (difference, -3%; 1-sided 95% CI, -10% to ∞; P = .004 for noninferiority). Pain scores were lower among patients in the 12F chest tube group (n = 54) vs the 24F group (n = 56) (mean VAS score, 22.0 mm vs 26.8 mm; adjusted difference, -6.0 mm; 95% CI, -11.7 to -0.2 mm; P = .04) and 12F chest tubes vs 24F chest tubes were associated with higher pleurodesis failure (30% vs 24%), failing to meet noninferiority criteria (difference, -6%; 1-sided 95% CI, -20% to ∞; P = .14 for noninferiority). Complications during chest tube insertion occurred more commonly with 12F tubes (14% vs 24%; odds ratio, 1.91; P = .20). CONCLUSIONS AND RELEVANCE: Use of NSAIDs vs opiates resulted in no significant difference in pain scores but was associated with more rescue medication. NSAID use resulted in noninferior rates of pleurodesis efficacy at 3 months. Placement of 12F chest tubes vs 24F chest tubes was associated with a statistically significant but clinically modest reduction in pain but failed to meet noninferiority criteria for pleurodesis efficacy. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN33288337.

Custom rotating hinge total knee arthroplasty in patients with poliomyelitis affected limbs.

PURPOSE: Total knee arthroplasty (TKA) in limbs affected by poliomyelitis is a technically challenging procedure. These patients often demonstrate acquired articular and metaphyseal angular deformities, bone loss, narrowness of the intramedullary canals, impaired quadriceps strength, flexion contractures and ligamentous laxity producing painful hyperextension. Thus, using condylar knee designs in these patients will likely result in early failure because of instability and abnormal load distribution. The aim of this study was to assess the outcomes associated with use of the customised (SMILES) rotating-hinge knee system at our institution for TKA in poliomyelitis-affected limbs. METHODS: We retrospectively reviewed the outcome of 14 TKAs using the (SMILES) prosthesis in 13 patients with limbs affected by poliomyelitis. All patients had painful unstable knees with hyperextension. There were ten females and three males with a mean age of 66 years (range 51-84) at time of surgery. Patients were followed up clinically, radiologically and functionally with the Oxford knee score (OKS). Mean follow-up was 72 months (16-156). RESULTS: There were no immediate or early complications. One patient fell and sustained a peri-prosthetic fracture at seven months requiring revision to a longer stem. Radiological evaluation showed satisfactory alignment with no signs of loosening in all cases. Mean OKS improved from 11.6 (4-18) to 31.5 (18-40) postoperatively (p < 0.001). CONCLUSION: The rotating hinge (SMILES) prosthesis is effective at relieving pain and improving function in patients with poliomyelitis. The device compensates well for ligamentous insufficiency as well as for any associated bony deformity.

Muscle atrophy and metal-on-metal hip implants: a serial MRI study of 74 hips.

BACKGROUND AND PURPOSE: Muscle atrophy is seen in patients with metal-on-metal (MOM) hip implants, probably because of inflammatory destruction of the musculo-tendon junction. However, like pseudotumors, it is unclear when atrophy occurs and whether it progresses with time. Our objective was to determine whether muscle atrophy associated with MOM hip implants progresses with time. PATIENTS AND METHODS: We retrospectively reviewed 74 hips in 56 patients (32 of them women) using serial MRI. Median age was 59 (23-83) years. The median time post-implantation was 83 (35-142) months, and the median interval between scans was 11 months. Hip muscles were scored using the Pfirrmann system. The mean scores for muscle atrophy were compared between the first and second MRI scans. Blood cobalt and chromium concentrations were determined. RESULTS: The median blood cobalt was 6.84 (0.24-90) ppb and median chromium level was 4.42 (0.20-45) ppb. The median Oxford hip score was 34 (5-48). The change in the gluteus minimus mean atrophy score between first and second MRI was 0.12 (p = 0.002). Mean change in the gluteus medius posterior portion (unaffected by surgical approach) was 0.08 (p = 0.01) and mean change in the inferior portion was 0.10 (p = 0.05). Mean pseudotumor grade increased by 0.18 (p = 0.02). INTERPRETATION: Worsening muscle atrophy and worsening pseudotumor grade occur over a 1-year period in a substantial proportion of patients with MOM hip implants. Serial MRI helps to identify those patients who are at risk of developing worsening soft-tissue pathology. These patients should be considered for revision surgery before irreversible muscle destruction occurs.

Functional outcome following primary total knee arthroplasty cannot be predicted using the initial post-operative radiograph.

Obtaining standardised post-operative radiographs following total knee arthroplasty is common practice. Little is known regarding how measurements taken from the initial post-operative radiograph correlate to functional outcome. The initial post-operative radiographs for 110 primary total knee arthroplasties were reviewed retrospectively. Femoral and tibial component alignment was measured by two independent consultant radiologists. Functional outcome was assessed by the Oxford Knee Score pre-operatively and one year post-operatively. Correlation was determined by Pearson correlation analysis. There was no significant correlation between the radiographic measurements with the one year post-operative Oxford Knee Score nor was there significant correlation with the difference in pre-operative and post-operative scores. The initial post-operative radiograph cannot be used as a tool to reliably predict functional outcome at one year.

Custom-made cement-linked mega prostheses: a salvage solution for complex periprosthetic femoral fractures.

Periprosthetic femoral fractures with long stem implants, poor bone stock and loosening pose a considerable surgical challenge. We describe a reconstruction technique using a custom-made mega-prosthesis, cement-linked to the femoral stem of a well-fixed existing implant. Clinical and radiological outcomes were assessed at our tertiary referral centre. There were 15 patients with a periprosthetic femoral fracture: 5 proximal and 10 distal femoral arthroplasties linked to existing femoral stems. The survival rate was 93.3% at a mean follow-up of 5.3 years (0.5-19.3) with 1 revision. We present a salvage technique with good intermediate-term outcomes for highly selected patients with complex periprosthetic femoral fractures, as another option to conventional fixation methods. Specifically, it allows immediate weight bearing and avoids some of the morbidity of total femoral arthroplasty or amputation.

The BioPoly Partial Resurfacing Knee Implant Provides Beneficial Clinical Outcomes: A Concise Follow-up, at 5 Years, of a Previous Report.

Abstract: We previously conducted a single-arm, prospective study in which 31 patients (mean age [and standard deviation], 42.5 ± 11.3 years) with cartilage lesions were treated with use of the BioPoly Partial Resurfacing Knee Implant. Treatment outcomes were compared with those reported for the standard of care, microfracture. We found that the mean KOOS (Knee injury and Osteoarthritis Outcome Score) Quality of Life score at 5 years in the BioPoly cohort was noninferior to (p = 0.004), and indeed greater than (p = 0.021), that in the microfracture cohort. The BioPoly cohort demonstrated improvement in the mean scores for all KOOS domains at every postoperative time point (p < 0.025). The mean score for the visual analog scale (VAS) for pain significantly improved (p < 0.025) at all time points up to 4 years and trended toward significant improvement at 5 years (p = 0.027). This study indicated that the BioPoly implant was safe, provided significant improvement starting at 6 months and continuing to 5 years, and provided greater improvement than microfracture for some outcome measures. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Same Day Biopsy and Treatment of Non-Melanoma Skin Cancer in Patients with Field Cancerization: A Retrospective Chart Study.

Background: Patients with field cancerization will develop numerous superficial non-melanoma skin cancers (NMSCs). Treating patients with field cancerization can be challenging and burdensome due to the numerous non-melanoma skin cancers (NMSCs) they develop and the frequent dermatology visits required for biopsy and treatment. Objective: The success rate of diagnosing and treating lesions suspicious for NMSCs on the same day is measured, immediately after biopsy. Methods: We retrospectively reviewed records of patients with same day lesion diagnosis and curettage treatment to determine diagnostic accuracy, treatment failure, and number needed to treat to reduce a follow-up treatment. Results: A total of 237 lesions underwent same day biopsy and treatment, of which the majority were NMSC (66%) or actinic keratosis (23%). Patients had at least 3 months and a median of 17 months follow-up. A total of 20 lesions either recurred or were deemed to require additional treatment. The number needed to treat (NNT) to prevent one follow-up treatment was 1.3. Limitations: sample size limited ability to determine risk factors for treatment failure. Conclusion: Simultaneous diagnosis and treatment of superficial NMSCs is a successful way of improving efficiency and patient satisfaction.

Executing and rationalizing the synthesis of a difluorinated analogue of a ring-expanded calystegine B2.

A difluorinated analogue of a ring-expanded calystegine B(2) and some N-protected species were prepared via microwave-mediated transannular ring-opening of an epoxyketone. The diastereofacial selectivity of the epoxidation reaction, which delivers the key intermediate, and the regioselectivity of the transannular reactions were analyzed by density functional theory (DFT) methods. The epoxidation stereoselectivity arises from simple steric control, whereas the ring-closure reactions are subject to thermodynamic control.

Pleiotrophin Interaction with Synthetic Glycosaminoglycan Mimetics.

Chondroitin sulfate (CS) E is the natural ligand for pleiotrophin (PTN) in the central nervous system (CNS) of the embryo. Some structures of PTN in solution have been solved, but no precise location of the binding site has been reported yet. Using 15N-labelled PTN and HSQC NMR experiments, we studied the interactions with a synthetic CS-E tetrasaccharide corresponding to the minimum binding sequence. The results agree with the data for larger GAG (glycosaminoglycans) sequences and confirm our hypothesis that a synthetic tetrasaccharide is long enough to fully interact with PTN. We hypothesize that the central region of PTN is an intrinsically disordered region (IDR) and could modify its properties upon binding. The second tetrasaccharide has two benzyl groups and shows similar effects on PTN. Finally, the last measured compound aggregated but beforehand, showed a behavior compatible with a slow exchange in the NMR time scale. We propose the same binding site and mode for the tetrasaccharides with and without benzyl groups.

Patient Impressions and Outcomes After Clinic-Based Hidradenitis Suppurativa Surgery.

IMPORTANCE: Surgical intervention is frequently needed to treat hidradenitis suppurativa (HS). Patient satisfaction is high based on previous studies, but reports of patient impressions of clinic-based operative experiences and postoperative recovery are limited. OBJECTIVE: To characterize patient impressions, outcomes, and recovery time after clinic-based surgical treatment of HS and examine patient characteristics associated with outcomes. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study included patients 12 years or older who underwent clinic-based surgical procedures for treatment of HS at a single subspecialty HS clinic at the University of North Carolina Department of Dermatology from April 2014 to December 2018. Data analysis was performed from January to September 2021. EXPOSURES: Clinic-based deroofing and excisional procedures performed as part of routine care. MAIN OUTCOMES AND MEASURES: The primary outcomes were patient-reported recurrence of HS at the site of surgery, patient satisfaction with the procedures and outcomes, and patient-reported pain and recovery associated with surgery obtained from electronic medical record review and patient questionnaires. RESULTS: Outcomes of 194 procedures for 78 patients (65 [83%] female; mean [SD] age, 35.1 [12.1] years) were analyzed. Self-reported rate of recurrence was 41% (79 procedures). Despite recurrence, most patients (148 procedures [76%]) were very satisfied with their surgical results. The median number of missed days of work or school was 2 (IQR, 1-7 days), and the median number of days until return to normal activity was 10 (IQR, 3-14 days). In addition, for 126 of the 194 procedures (65%), patients stated that pain during an HS flare was worse than pain during surgical recovery. CONCLUSIONS AND RELEVANCE: In this cohort study, patients reported high rates of satisfaction with clinic-based HS surgery. Recovery was typically rapid, with most patients rating postsurgical pain as less severe than their HS pain.

Ischial screw fixation can prevent cup migration in 3D-printed custom acetabular components for complex hip reconstruction.

INTRODUCTION: Custom acetabular components have become an established method of treating massive acetabular bone defects in hip arthroplasty. Complication rates, however, remain high and migration of the cup is still reported. Ischial screw fixation (IF) has been demonstrated to improve mechanical stability for non-custom, revision arthroplasty cup fixation. We hypothesize that ischial fixation through the flange of a custom acetabular component aids in anti-rotational stability and prevention of cup migration. METHODS: Electronic patient records were used to identify a consecutive series of 49 custom implants in 46 patients from 2016 to 2022 in a unit specializing in complex joint reconstruction. IF was defined as a minimum of one screw inserted into the ischium passing through a hole in a flange on the custom cup. The mean follow-up time was 30 months. IF was used in 36 cups. There was no IF in 13 cups. No difference was found between groups in age (68.9 vs. 66.3, P = 0.48), BMI (32.3 vs. 28.2, P = 0.11) or number of consecutively implanted cups (3.2 vs. 3.6, P = 0.43). Aseptic loosening with massive bone loss was the primary indication for revision. There existed no difference in Paprosky grade between the groups (P = 0.1). 14.2% of hips underwent revision and 22.4% had at least one dislocation event. RESULTS: No ischial fixation was associated with a higher risk of cup migration (6/13 vs. 2/36, X2 = 11.5, P = 0.0007). Cup migration was associated with an increased risk for all cause revision (4/8 vs. 3/38, X2 = 9.96, P = 0.0016, but not with dislocation (3/8 vs. 8/41, X2 = 1.2, P = 0.26). CONCLUSION: The results suggest that failure to achieve adequate ischial fixation, with screws passing through the flange of the custom component into the ischium, increases the risk of cup migration, which, in turn, is a risk factor for revision.

Characterization of per- and polyfluoroalkyl substances on fire suppression system piping and optimization of removal methods.

Fire suppression systems are known to be impacted with residual, entrained per- and polyfluoroalkyl substances (PFASs) because of historical use of aqueous film forming foam (AFFF) and fluoroprotein foam. Amphiphilic PFASs aggregate at liquid:solid interfaces creating a hydrophobic layer which reduces the effectiveness of water to remove PFAS from layered surfaces. When fire suppression systems are transitioned to fluorine free foam (F3) without appropriate cleaning, residual PFASs associated with the surfaces of the fire suppression system can contaminate the replacement F3. Release of residual PFASs from fire suppression systems into F3 has been documented; however, little is known about the residual PFASs associated with the surfaces of the fire suppression systems. More information is needed to develop methods to appropriately remove PFASs from fire suppression systems to prevent costly and inefficient foam transitioning and preserve the PFAS-free benefit of F3. The objective of this work was to evaluate the distribution and composition of PFASs on hangar piping exposed to PFAS-containing firefighting foam for a prolonged period. Two assessment methods were used: 1) extractions with methanol, water, and a proprietary aqueous organic solvent (Fluoro Fighter™); and 2) direct imaging methods of the surface. Extractions were analyzed with mass spectrometry and combustion ion chromatography. Results indicate pipe in contact with PFAS-containing firefighting foam can amass approximately 10 µg/cm2 of surface-associated PFAS residual following decades of exposure. Fluoro Fighter demonstrated higher PFAS removal per surface area of pipe than methanol (p = 0.007) or water extraction (p < 0.0001). Scanning electron microscope (SEM) images of the hangar piping reveal deposits suspected to be self-assembled PFAS layers, as evidenced by examination of pipe surfaces using X-ray photoelectron spectroscopy (XPS), which revealed atomic fluorine on the surface of the pipe.

Stem cell transplantation for the treatment of osteochondral defects of the knee: Operative technique for a single-stage transplantation procedure using bone marrow-derived mesenchymal stem cells.

BACKGROUND: Autologous chondrocyte implantation (ACI) is a NICE-approved technique to regenerate hyaline cartilage in chondral and osteochondral defects (OCDs). The drawbacks of ACI include that it requires a two-stage approach, involves a lengthy rehabilitation process and is expensive. Bone marrow harvest with mesenchymal stem cell transplantation using a single-stage procedure and an accelerated rehabilitation programme has been developed to overcome this. The aim of this paper is to describe the surgical technique for stem cell transplantation of the knee for OCDs with reference to case examples. METHODS: The surgical technique for stem cell transplantation of the knee for OCDs is described, with reference to three cases. Magnetic resonance imaging was performed at six months postoperatively. RESULTS: The surgical technique is described in this paper. The three patient cases described all improved clinically with reduced pain and improved function at a minimum of six months follow-up. CONCLUSIONS: Stem cell transplantation has the potential to produce favourable outcomes for patients with osteochondral defects of the knee. This single-stage approach and accelerated rehabilitation is associated with reduced financial costs. A long-term prospective study of this technique is currently underway at our institution and randomised controlled trials are planned to demonstrate the effectiveness over other techniques.

Infected prosthetic knee replacement: What to do and what not to do.

This article is an expansion of a lecture given in the British Orthopaedic Association (BOA) Congress in Liverpool in 2019 as part of a symposium on infected knee replacement. It is designed to provide pointers and advice to surgeons on how these patients can be referred, investigated, and managed. The management of periprosthetic infection necessitates many decisions to be made to provide the patient with the best advice and treatment. This is a discussion of the philosophies of periprosthetic knee infection. It is not a definitive guide nor a metanalysis of scientific papers. These are the subjective views of the author and generalise decision making. All decisions should remain tailored to the patient's needs.

The uncrossed-doubled patellar tendon: A novel imaging finding.

A spectrum of anatomic variants of the conventional single patellar tendon have been described however a double patellar tendon is a highly rare finding, which has only been described once before where a cross-over tendon morphology was illustrated. We report the case of a 46-year-old man with a 3 month history of left knee pain who was found to have an incidental double patellar tendon without cross-over, with one deep bundle demonstrating a more conventional patellar tendon course, paralleled by a second anatomically-distinct superficial bundle of differing morphology coursing anterolateral to the deep conventional bundle, explicitly connecting patella to tibial tuberosity. A comprehensive understanding of the anatomic variations of the patellar tendon is essential for both radiologist and clinician to deliver safe clinical practice. We present a rare case of an uncrossed-doubled patellar tendon, which to our knowledge, has never been reported.

Sexual orientation and adolescent substance use: a meta-analysis and methodological review.

AIMS: Several decades of research have shown that lesbian, gay and bisexual (LGB) adults are at high risk for substance use and substance use disorders (SUDs). These problems may often start prior to young adulthood; however, relatively little is known about risk for substance use in LGB adolescents. The primary aims of this paper were to conduct a meta-analysis of the relationship between sexual orientation and adolescent substance use and a systematic review and critique of the methodological characteristics of this literature. METHODS: Medical and social science journals were searched using Medline and PsychInfo. Studies were included if they tested the relationship between sexual orientation and adolescent substance use. Eighteen published studies were identified. Data analysis procedures followed expert guidelines, and used National Institutes of Health (NIH)-sponsored meta-analysis software. RESULTS: LGB adolescents reported higher rates of substance use compared to heterosexual youth (overall odds ratio = 2.89, Cohen's d = 0.59). Effect sizes varied by gender, bisexuality status, sexual orientation definition and recruitment source. None of the studies tested mediation and only one tested moderation. One employed a matched comparison group design, one used a longitudinal design, and very few controlled for possible confounding variables. CONCLUSIONS: The odds of substance use for LGB youth were, on average, 190% higher than for heterosexual youth and substantially higher within some subpopulations of LGB youth (340% higher for bisexual youth, 400% higher for females). Causal mechanisms, protective factors and alternative explanations for this effect, as well as long-term substance use outcomes in LGB youth, remain largely unknown.