Discordance Between Patient and Surgeon Satisfaction After Total Joint Arthroplasty

We surveyed 331 patients undergoing total hip or knee arthroplasty pre-operatively, and patients and surgeons were both surveyed 6 and 12 months post-operatively. We identified variables (demographic factors, operative factors and patient expectations) as possible predictors for discordance in patient–surgeon satisfaction. At 12 months, 94.5% of surgeons and 90.3% of patients recorded satisfaction with the outcome. The discordance between patient and surgeon satisfaction was mainly due to patient dissatisfaction–surgeon satisfaction. In an adjusted analysis, the strongest predictors of discordance in patient–surgeon satisfaction were unmet patient expectations and the presence of complications. Advice to potential joint arthroplasty candidates regarding the decision to proceed with surgery should be informed by patient reported outcomes, rather than the surgeon's opinion of the likelihood of success.     

One hertz repetitive transcranial magnetic stimulation over dorsal premotor cortex enhances offline motor memory consolidation for sequence‐specific implicit learning

Consolidation of motor memories associated with skilled practice can occur both online, concurrent with practice, and offline, after practice has ended. The current study investigated the role of dorsal premotor cortex (PMd) in early offline motor memory consolidation of implicit sequence‐specific learning. Thirty‐three participants were assigned to one of three groups of repetitive transcranial magnetic stimulation (rTMS) over left PMd (5 Hz, 1 Hz or control) immediately following practice of a novel continuous tracking task. There was no additional practice following rTMS. This procedure was repeated for 4 days. The continuous tracking task contained a repeated sequence that could be learned implicitly and random sequences that could not. On a separate fifth day, a retention test was performed to assess implicit sequence‐specific motor learning of the task. Tracking error was decreased for the group who received 1 Hz rTMS over the PMd during the early consolidation period immediately following practice compared with control or 5 Hz rTMS. Enhanced sequence‐specific learning with 1 Hz rTMS following practice was due to greater offline consolidation, not differences in online learning between the groups within practice days. A follow‐up experiment revealed that stimulation of PMd following practice did not differentially change motor cortical excitability, suggesting that changes in offline consolidation can be largely attributed to stimulation‐induced changes in PMd. These findings support a differential role for the PMd in support of online and offline sequence‐specific learning of a visuomotor task and offer converging evidence for competing memory systems.     

Transduction of pluripotent human hematopoietic stem cells demonstrated by clonal analysis after engraftment in immune-deficient mice.

Gene transduction of pluripotent human hematopoietic stem cells (HSCs) is necessary for successful gene therapy of genetic disorders involving hematolymphoid cells. Evidence for transduction of pluripotent HSCs can be deduced from the demonstration of a retroviral vector integrated into the same cellular chromosomal DNA site in myeloid and lymphoid cells descended from a common HSC precursor. CD34+ progenitors from human bone marrow and mobilized peripheral blood were transduced by retroviral vectors and used for long-term engraftment in immune-deficient (beige/nude/XIS) mice. Human lymphoid and myeloid populations were recovered from the marrow of the mice after 7-11 months, and individual human granulocyte-macrophage and T-cell clones were isolated and expanded ex vivo. Inverse PCR from the retroviral long terminal repeat into the flanking genomic DNA was performed on each sorted cell population. The recovered cellular DNA segments that flanked proviral integrants were sequenced to confirm identity. Three mice were found (of 24 informative mice) to contain human lymphoid and myeloid populations with identical proviral integration sites, confirming that pluripotent human HSCs had been transduced.