This is me! Neural correlates of self-recognition in 6- to 8-month-old infants.

Historically, evidence of self-recognition in development has been associated with the "rouge test"; however, this has been often criticized for providing a reductionist picture of self-conscious behavior. With two event-related potential (ERP) experiments, this study investigated the origin of self-recognition. Six- to eight-month-old infants (42 males and 35 females, predominately White, tested in the UK in 2022-2023) were presented with images of their face, another peer's face, and their mother's face (N = 38, Exp.1), and images of their own face morphed into another peer's face (N = 39, Exp.2). Results showed an enhanced P100 in infants' ERP response to their own face compared to others' faces (Exp.1 only), suggesting the presence of an enhanced attentional mechanism to one own's face as early as 6 months.

Isolated Tibial Polyethylene Insert Exchange After Total Knee Arthroplasty for Treatment of Instability and/or Polyethylene Wear.

INTRODUCTION: Isolated tibial polyethylene insert exchange (ITPIE) as a treatment for instability and polyethylene wear after total knee arthroplasty (TKA) remains controversial with studies reporting varied results. The purpose of this study is to evaluate the survival and outcomes of ITPIE performed for treatment of instability with or without polyethylene wear after TKA. MATERIALS AND METHODS: A query of a private practice arthroplasty registry revealed 364 patients (390 knees) treated with ITPIE for instability and/or polyethylene wear after TKA between 1997 and 2019. Mean age was 66.8 years, mean body mass index (BMI) was 33.8 kg/m2, and 59% of patients were female. ITPIE for infection, tibiofemoral aseptic loosening, arthrofibrosis, poor wound healing, and extensor mechanism failure were excluded. All patients had well-fixed and well-aligned components prior to surgery. RESULTS: Mean follow up was 5.9 years. Knee Society Clinical (KSC) scores improved preoperatively from 55 to 76 postoperatively (p <0.001). Thirty knees (7.7%) required re-revision: 15 (3.8%) for ongoing instability, seven aseptic loosening, three infection, two patellofemoral maltracking, one patellar fracture, one metal allergy, and one revised elsewhere for cause unknown. Kaplan-Meier analysis revealed survival of 93.1% (95% CI: ±1.5%) at five years, 84.7% (95% CI: ±3.5%) at 10 years, and 80.5% (95% CI: ±4.4%) at 21 years. CONCLUSIONS: ITPIE is a reliable treatment for instability and/or polyethylene wear after TKA in the presence of well-fixed and well-aligned components with good survival and clinical improvement. The less invasive nature and reduced risk for bone loss make it an attractive option versus full revision.

Role of the kinetic chain in shoulder rehabilitation: does incorporating the trunk and lower limb into shoulder exercise regimes influence shoulder muscle recruitment patterns? Systematic review of electromyography studies.

OBJECTIVE: To investigate the influence of trunk and lower limb motion on electromyography (EMG) muscle activity and recruitment patterns around the shoulder. DESIGN: Systematic review. DATA SOURCES: MEDLINE, CINAHL, PEDro, AMED, PubMed, Cochrane Central Register of Controlled trials, Cochrane Database of Systematic reviews, SportsDiscuss and PROSPERO. ELIGIBILITY CRITERIA: Studies investigating both multiregional kinetic chain (KC) shoulder exercises and localised non-kinetic chain (nKC) shoulder exercises in healthy subjects under the same experimental conditions were included in this review. RESULTS: KC exercises produced greater EMG activation levels in 5 of 11 studies for the lower trapezius. Of the remaining studies, five found no difference between the exercise types and one favoured nKC exercises. KC exercises produced greater EMG activation levels in 5 of 11 studies for the serratus anterior. Of the remaining studies, three reported the opposite and three found no significant difference between the exercise types. nKC exercises produced greater EMG activation in infraspinatus in three of four studies. KC exercises produced the lowest trapezius muscle ratios in all studies. Studies investigating the upper trapezius, middle trapezius, supraspinatus, subscapularis, biceps brachii, latifissimus dorsi, pectoralis major, deltoid, and trapezius and serratus anterior ratios showed inconsistency. CONCLUSION: This review found evidence that integrating the KC during shoulder rehabilitation may increase axioscapular muscle recruitment, produce lower trapezius muscle ratios and reduce the demands on the rotator cuff. Stepping appears preferable to squatting. PROSPERO REGISTRATION NUMBER: CRD42015032557, 2015.