Abstract. The aim of this study was to determine the incidence, annual trend, and perioperative outcomes and identify risk factors of early-onset (≤90 d) deep surgical site infection (SSI) following primary total hip arthroplasty (THA) for osteoarthritis. We performed a retrospective study using prospectively collected patient-level data from January 2013 to March 2020. The diagnosis of deep SSI was based on the published Centre for Disease Control/National Healthcare Safety Network (CDC/NHSN) definition. The Mann–Kendall trend test was used to detect monotonic trends. Secondary outcomes were 90 d mortality and 90 d readmission. A total of 22 685 patients underwent primary THA for osteoarthritis. A total of 46 patients had a confirmed deep SSI within 90 d of surgery representing a cumulative incidence of 0.2 %. The annual infection rate decreased over the 7-year study period (p=0.026). Risk analysis was performed on 15 466 patients. Risk factors associated with early-onset deep SSI included a BMI > 30 kg m−2 (odds ratio (OR) 3.42 [95 % CI 1.75–7.20]; p<0.001), chronic renal disease (OR, 3.52 [95 % CI 1.17–8.59]; p=0.011), and cardiac illness (OR, 2.47 [1.30–4.69]; p=0.005), as classified by the Canadian Institute for Health Information. Early-onset deep SSI was not associated with 90 d mortality (p=0.167) but was associated with an increased chance of 90 d readmission (p<0.001). This study establishes a reliable baseline infection rate for early-onset deep SSI after THA for osteoarthritis through the use of a robust methodological process. Several risk factors for early-onset deep SSI are potentially modifiable, and therefore targeted preoperative interventions of patients with these risk factors is encouraged.

Circadian rhythms modulate behavioral processes over a 24 h period through clock gene expression. What is largely unknown is how these molecular influences shape neural activity in different brain areas. The clock gene Per2 is rhythmically expressed in the striatum and the cerebellum and its expression is linked with daily fluctuations in extracellular dopamine levels and D2 receptor activity. Electrophysiologically, dopamine depletion enhances striatal local field potential (LFP) oscillations. We investigated if LFP oscillations and synchrony were influenced by time of day, potentially via dopamine mechanisms. To assess the presence of a diurnal effect, oscillatory power and coherence were examined in the striatum and cerebellum of rats under urethane anesthesia at four different times of day zeitgeber time (ZT1, 7, 13 and 19—indicating number of hours after lights turned on in a 12:12 h light-dark cycle). We also investigated the diurnal response to systemic raclopride, a D2 receptor antagonist. Time of day affected the proportion of LFP oscillations within the 0–3 Hz band and the 3–8 Hz band. In both the striatum and the cerebellum, slow oscillations were strongest at ZT1 and weakest at ZT13. A 3–8 Hz oscillation was present when the slow oscillation was lowest, with peak 3–8 Hz activity occurring at ZT13. Raclopride enhanced the slow oscillations, and had the greatest effect at ZT13. Within the striatum and with the cerebellum, 0–3 Hz coherence was greatest at ZT1, when the slow oscillations were strongest. Coherence was also affected the most by raclopride at ZT13. Our results suggest that neural oscillations in the cerebellum and striatum, and the synchrony between these areas, are modulated by time of day, and that these changes are influenced by dopamine manipulation. This may provide insight into how circadian gene transcription patterns influence network electrophysiology. Future experiments will address how these network alterations are linked with behavior.

Background: Surgical fixation of tibial plateau fracture in elderly patients with open reduction and internal fixation (ORIF) provides inferior outcomes compared with younger patients. Primary total knee arthroplasty (TKA) may be of benefit in elderly patients with a combination of osteoporotic bone and metaphyseal comminution. However, there continues to be conflicting evidence on the use of TKA for primary treatment of tibial plateau fracture. This systematic review was performed to quantify the outcomes and perioperative complication rates of TKA for primary treatment of tibial plateau fracture. Materials and methods: A comprehensive search of MEDLINE, Embase, and PubMed databases from inception through March 2018 was performed in accordance with PRISMA guidelines. Two reviewers independently screened papers for inclusion and identified studies featuring perioperative complications and outcomes of primary TKA for tibial plateau fracture. Weighted means and standard deviations are presented for each outcome. Results: Seven articles (105 patients) were eligible for inclusion. All-cause mortality was 4.75 ± 4.85%. The total complication rate was 15.2 ± 17.3%. Regarding outcomes, Knee Society scores were most commonly reported. The average Knee Society Knee Score was 85.6 ± 5.5, while the average Knee Society Function Score was 64.6 ± 13.7. Average range of motion at final follow-up was 107.5 ± 10.0°. Conclusions: Primary TKA for select tibial plateau fractures has acceptable clinical outcomes but does not appear to be superior to ORIF. It may be appropriate to treat certain geriatric patients with TKA to allow for early mobilization and reduce the need for reoperation. Other factors may need to be considered in deciding the optimal treatment. Level of evidence: Level III.

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BackgroundThis review compares the outcomes and complication rates of three surgical strategies used for the management of symptomatic os acromiale. The purpose of this study was to help guide best practice recommendations.MethodsA systematic review of nine prospective studies, seven retrospective studies, and three case studies published across ten countries between 1993 and 2018 was performed. Adult patients (i.e., ≥ 18 years of age) with a symptomatic os acromiale that failed nonoperative management were included in this review. Surgical techniques utilized within the included studies include excision, acromioplasty, and open reduction and internal fixation (ORIF). The primary outcomes of interest included patient satisfaction. Range of motion and several standardized outcome measurement tools were also included in the final analysis.ResultsPatient satisfaction was highest in the excision and ORIF groups, with 92% and 82% of patients reporting good to excellent postoperative results, respectively, compared to 63% in the acromioplasty group. All three patient groups experienced improvements in postoperative outcomes (i.e., active range of motion and patient-reported outcome scores). The excision group experienced a complication rate of 1%, while the acromioplasty group experienced a complication rate of 11% and the ORIF group a rate of 67%.ConclusionThis study reports on the largest sample of patients who underwent surgical treatment for a symptomatic os acromiale. We have demonstrated that excision of the os with meticulous repair of the deltoid resulted in the best clinical outcomes with the least complications. In healthy adult patients with a large os fragment and a normal rotator cuff, surgical fixation may provide increased preservation of deltoid function while offering good to excellent patient satisfaction. However, patients must be informed that a second procedure may be required to remove symptomatic hardware.

Objectives: The aim of this study is to examine whether surgical treatment of early onset scoliosis (EOS) with magnetically controlled growing rods (MCGRs) or a vertical expandable prosthetic titanium rib (VEPTR) resulted in fewer short-term (24 months) complications and reoperations.Background: EOS is a challenging problem for spine surgeons that has been managed with different growthfriendly instrumentation systems. Although rib-based devices encourage spinal growth via regular lengthening, the high rate of complications and reoperations leads us to use spine-based devices such as MCGRs to mitigate this concern.Methods: A total of 35 EOS patients were included in the study. Twenty patients were included in the VEPTR group, and 15 patients were included in the MCGR group. Demographic data and 2 years of postoperative complications and reoperations were reviewed retrospectively. As secondary outcomes, radiographic outcomes were reported preoperatively and 1 year after surgery. Indications for this technique and complications were collected from the charts.Results: Demographic data showed no significant differences between the 2 groups. Significant differences were found in the complications rate at 2 years, with 65% complications in the VEPTR group and 13.3% complications in the MCGR group (P , .001). The reoperation rate at 2 years was also significantly higher in the VEPTR group, with 50% versus 13.3% in the MCGR group (P ¼ .0009). As secondary outcomes, radiological parameters such as main curve Cobb angle correction (P ¼ .001) and apical vertebral translation (P ¼ .002) were significantly higher in the MCGR group. Significant differences were also found in sagittal profile parameters; T1-T12 and T1-S1 were significantly higher in the MCGR group (P , .001).Conclusions: According to our results, VEPTR has significantly higher complication and reoperation rates at 2 years postsurgery compared with MCGR.

Aims Total hip arthroplasty (THA) with dual-mobility components (DM-THA) has been shown to decrease the risk of dislocation in the setting of a displaced neck of femur fracture compared to conventional single-bearing THA (SB-THA). This study assesses if the clinical benefit of a reduced dislocation rate can justify the incremental cost increase of DM-THA compared to SB-THA. Methods Costs and benefits were established for patients aged 75 to 79 years over a five-year time period in the base case from the Canadian Health Payer’s perspective. One-way and probabilistic sensitivity analysis assessed the robustness of the base case model conclusions. Results DM-THA was found to be cost-effective, with an estimated incremental cost-effectiveness ratio (ICER) of CAD $46,556 (£27,074) per quality-adjusted life year (QALY). Sensitivity analysis revealed DM-THA was not cost-effective across all age groups in the first two years. DM-THA becomes cost-effective for those aged under 80 years at time periods from five to 15 years, but was not cost-effective for those aged 80 years and over at any timepoint. To be cost-effective at ten years in the base case, DM-THA must reduce the risk of dislocation compared to SB-THA by at least 62%. Probabilistic sensitivity analysis showed DM-THA was 58% likely to be cost-effective in the base case. Conclusion Treating patients with a displaced femoral neck fracture using DM-THA components may be cost-effective compared to SB-THA in patients aged under 80 years. However, future research will help determine if the modelled rates of adverse events hold true. Surgeons should continue to use clinical judgement and consider individual patients’ physiological age and risk factors for dislocation. Cite this article: Bone Joint J 2021;103-B(12):1783–1790.

BackgroundVenous thromboembolism, specifically pulmonary embolism, is a rare complication following elective pediatric orthopedic surgery. Bilateral pulmonary embolism with associated pulmonary hemorrhage/infarct without concomitant deep vein thrombosis has never been reported following routine anterior cruciate ligament reconstruction in an adolescent.Case presentationA 16-year-old white girl presented with acute onset shortness of breath and pleuritic chest pain 6 days following elective anterior cruciate ligament reconstruction. After performing a thorough work-up, she was diagnosed as having provoked bilateral pulmonary embolism with associated pulmonary hemorrhage without concomitant deep vein thrombosis. She was treated successfully with 3 months of anticoagulation therapy with daily Lovenox (enoxaparin) injections.ConclusionsSymptomatic bilateral pulmonary embolism may have a good prognosis if it is diagnosed early and treated appropriately. It is important to appreciate the risk of provoked thromboembolic events in healthy adolescents undergoing arthroscopic knee surgery.