Driving Forces for Outpatient Total Hip and Knee Arthroplasty with Enhanced Recovery After Surgery Protocols: A Narrative Review.

PURPOSE OF REVIEW: To explore the recent developments and trends in the anesthetic and surgical practices for total hip and total knee arthroplasty and discuss the implications for further outpatient total joint arthroplasty procedures. RECENT FINDINGS: Between 2012 and 2017 there was an 18.9% increase in the annual primary total joint arthroplasty volume. Payments to physicians falling by 7.5% (14.9% when adjusted for inflations), whereas hospital reimbursements and charges increased by 0.3% and 18.6%, respectively. Total knee arthroplasty and total hip arthroplasty surgeries were removed from the Medicare Inpatient Only in January 2018 and January 2020, respectively leading to same-day TKA surgeries increases from 1.2% in January 2016 to 62.4% by December 2020 Same-day volumes for THA surgery increased from 2% in January 2016 to 54.5% by December 2020. Enhanced Recovery After Surgery (ERAS) protocols have revolutionized modern anesthesia and surgery practices. Centers for Medicare Services officially removed total joint arthroplasty from the inpatient only services list, opening a new door for improved cost savings to patients and the healthcare system alike. In the post-COVID healthcare system numerous factors have pushed increasing numbers of total joint arthroplasties into the outpatient, ambulatory surgery center setting. Improved anesthesia and surgical practices in the preoperative, intraoperative, and postoperative settings have revolutionized pain control, blood loss, and ambulatory status, rendering costly hospital stays obsolete in many cases. As the population ages and more total joint procedures are performed, the door is opening for more orthopedic procedures to exit the inpatient only setting in favor of the ambulatory setting.

Quantitative measures of motor development in Angelman syndrome.

Angelman Syndrome is a rare neurodevelopmental disorder characterized by developmental delay, lack of speech, seizures, intellectual disability, characteristic behavior, and movement disorders. Clinical gait analysis provides the opportunity for movement quantification to investigate an observed maladaptive change in gait pattern and offers an objective outcome of change. Pressure-sensor-based technology, inertial and activity monitoring, and instrumented gait analysis (IGA) were employed to define motor abnormalities in Angelman syndrome. Temporal-spatial gait parameters of persons with Angelman Syndrome (pwAS) show deficiencies in gait performance through walking speed, step length, step width, and walk ratio. pwAS walk with reduced step lengths, increased step width, and greater variability. Three-dimensional motion kinematics showed increased anterior pelvic tilt, hip flexion, and knee flexion. PwAS have a walk ratio more than two standard deviations below controls. Dynamic electromyography showed prolonged activation of knee extensors, which was associated with a decreased range of motion and the presence of hip flexion contractures. Use of multiple gait tracking modalities revealed that pwAS exhibit a change in gait pattern to a flexed knee gait pattern.  Cross-sectional studies of individuals with AS show a regression toward this maladaptive gait pattern over development in pwAS ages 4-11. PwAS unexpectedly did not have spasticity associated with change in gait pattern. Multiple quantitative measures of motor patterning may offer early biomarkers of gait decline consistent with critical periods of intervention, insight into appropriate management strategies, objective primary outcomes, and early indicators of adverse events.

7,8-Dihydro-8-oxoguanosine Lesions Inhibit the Theophylline Aptamer or Change Its Selectivity.

Aptamers are attractive constructs due to their high affinity/selectivity towards a target. Here 7,8-dihydro-8-oxoguanosine (8-oxoG) has been used, due in part to its unique H-bonding capabilities (Watson-Crick or Hoogsteen), to expand the "RNA alphabet". Its impact on the theophylline RNA aptamer was explored by modifying its binding pocket at positions G11, G25, or G26. Structural probing, with RNases A and T1 , showed that modification at G11 leads to a drastic structural change, whereas the G25-/G26-modified analogues exhibited cleavage patterns similar to that of the canonical construct. The recognition properties towards three xanthine derivatives were then explored through thermophoresis. Modifying the aptamer at position G11 led to binding inhibition. Modification at G25, however, changed the selectivity towards theobromine (Kd ≈160 µm), with a poor affinity for theophylline (Kd >1.5 mm) being observed. Overall, 8-oxoG can have an impact on the structures of aptamers in a position-dependent manner, leading to altered target selectivity.

Experimental and theoretical rationalization for the base pairing abilities of inosine, guanosine, adenosine, and their corresponding 8-oxo-7,8-dihydropurine, and 8-bromopurine analogues within A-form duplexes of RNA.

Inosine is an important RNA modification, furthermore RNA oxidation has gained interest due, in part, to its potential role in the development/progression of disease as well as on its impact on RNA structure and function. In this report we established the base pairing abilities of purine nucleobases G, I, A, as well as their corresponding, 8-oxo-7,8-dihydropurine (common products of oxidation at the C8-position of purines), and 8-bromopurine (as probes to explore conformational changes), derivatives, namely 8-oxoG, 8-oxoI, 8-oxoA, 8-BrG, and 8-BrI. Dodecamers of RNA were obtained using standard phosphoramidite chemistry via solid-phase synthesis, and used as models to establish the impact that each of these nucleobases have on the thermal stability of duplexes, when base pairing to canonical and noncanonical nucleobases. Thermal stabilities were obtained from thermal denaturation transition (Tm ) measurements, via circular dichroism (CD). The results were then rationalized using models of base pairs between two monomers, via density functional theory (DFT), that allowed us to better understand potential contributions from H-bonding patterns arising from distinct conformations. Overall, some of the important results indicate that: (a) an anti-I:syn-A base pair provides thermal stability, due to the absence of the exocyclic amine; (b) 8-oxoG base pairs like U, and does not induce destabilization within the duplex when compared to the pyrimidine ring; (c) a U:G wobble-pair is only stabilized by G; and (d) 8-oxoA displays an inherited base pairing promiscuity in this sequence context. Gaining a better understanding of how this oxidatively generated lesions potentially base pair with other nucleobases will be useful to predict various biological outcomes, as well as in the design of biomaterials and/or nucleotide derivatives with biological potential.

Effect of split posterior tibialis tendon transfer on foot progression angle in children with cerebral palsy.

OBJECTIVES: A common orthopedic issue for patients with spastic cerebral palsy (CP) is hindfoot varus deformity. One method of treatment is the split posterior tibialis tendon transfer (SPOTT). There is limited literature on the effect of SPOTT on foot progression angle (FPA) in children with CP who have equinovarus deformities. The objective of our study was to evaluate the change in FPA after SPOTT to determine if this procedure can improve FPA. RESEARCH QUESTION: This study aims to determine what axial changes are generated from a split posterior tibial tendon transfer in children with CP. METHODS: We performed a retrospective analysis of all ambulatory children with a diagnosis of CP who underwent SPOTT at our institution. Patients with bony rotational procedures were excluded. Descriptive statistics including mean and standard deviation (SD) were used to characterize continuous variables. Paired t-tests were used to evaluate outcomes, in which a target outcome was defined as a post-operative FPA between 0-10° of external rotation. RESULTS: 44 limbs were included. Demographics were as follows: 26/13 female/male; mean age[SD] (years): 9.8[3.5]; 30 hemiplegic, 9 diplegic, and 1 triplegic. Of the 44 limbs, 18 limbs had a target outcome, 4 had no change, and 22 had a non-target outcome. Of the 22 with an outcome outside of the target, 4 limbs trended away from a target outcome. The overall change in FPA measured was - 10.9 ± 14.7° (p < 0.0001) Age at time of surgery, CP involvement, pre-operative FPA, and GMFCS level were not predictors of outcome (p > 0.05). CONCLUSIONS: SPOTT produced a change of 10.9° external rotation in FPA post-operatively and its effects should be considered when planning a SEMLS.

Rectus femoris transfers with and without a hamstring lengthening will not change hip kinematics in children with cerebral palsy.

BACKGROUND: A rectus femoris transfer (RFT) surgery with and without a hamstring lengthening (HSL) is used to treat stiff-knee gait in children with cerebral palsy (CP). While current literature has reported that a RFT surgery improves the kinematics at the knee, little is known about the kinematic changes at the hip. RESEARCH QUESTION: Does a RFT surgery change hip joint kinematics in children with CP? METHODS: This retrospective study included children (<18 years old) diagnosed with CP, who underwent a RFT procedure, and who were seen at our institution's accredited clinical motion laboratory. Patients with both pre- and post-operative gait analysis were identified and comparison between those analyses were performed to identify kinematic differences at the hip and knee. A total of 66 legs from 46 children (mean age: 11.1 ± 3.6) met the inclusion criteria. RESULTS: Overall results revealed that a RFT did not change kinematics at the hip [p > 0.05], however, a RFT did increase the maximum knee flexion during the swing period [Mean Difference Post - Pre: 8.3°, 95% CI: 4.9-11.8, p < 0.0001]. Additionally, it was found that changes in hip extension during the terminal stance phase were significantly different between the combined RFT and HSL compared to solely an RFT. The results of this study also revealed that children whose stiff-knee gait did not improve, tended to have increased hip external rotation during terminal stance and swing and greater hip extension during terminal stance, compared to children whose stiff-knee gait did improve. SIGNIFICANCE: Overall, a RFT with and without a HSL surgery improves hip and knee kinematics in the sagittal plane, however, improvements at the hip were not clinically significant. As a result, a RFT or a combined RFT with HSL should not be used to change hip kinematics in children with CP.

Postoperative Immobilization After Hip Reconstruction in Cerebral Palsy: No Difference Between Hip Spica and Abduction Pillow.

Purpose: This study aims to compare radiographic outcomes and complication rates of immobilization with an abduction pillow to spica casting for postoperative care after a hip reconstruction with varus derotational proximal femur osteotomy (VDRO) with or without pelvic osteotomy for children with cerebral palsy (CP). Methods: 233 children (1-18 years old) diagnosed with CP that underwent VDRO with or without pelvic osteotomy were identified, of which 188 patients were immobilized with a spica cast and 45 were immobilized with an abduction pillow, based on surgeon preference. 123 (65%) in the Spica group and 21 (47%) in the pillow group had pelvic osteotomies. Demographic data and complication rates were collected. Radiographic parameters, including anatomic medial proximal femoral angle (aMPFA), acetabular index (AI) and migration percentage (MP), were measured for each patient at the completion of surgery, six weeks post-operatively, and one year post-operatively. Results: There was not a statistically significant difference in BMI (p = 0.285), gender distribution (p = 0.984), or median follow-up time (p = 0.314) between groups. Rates of complications were consistent among groups with no differences in instances of delayed unions (p = 0.10), subluxations (p = 0.55), infection (p = 0.71), or non-unions (p = 0.10). There was no statistically significant difference in number of patients with an ideal aMPFA, AI, or MP (p = 0.44, p = 0.19, p = 1.00) at one year post-operatively. Conclusions: Immobilization with an abduction pillow is a safe and effective alternative to hip spica casting following hip reconstruction.

Using Motion Analysis in the Evaluation, Treatment & Rehabilitation of Pediatric & Adolescent Knee Injuries: A Review of the Literature.

Three-dimensional motion capture systems may improve evaluation, treatment, and rehabilitation of knee injuries, because quantitative assessment of the knee improves understanding of biomechanical mechanisms. The benefit of using motion analysis in pediatric sports medicine is that it allows closer and more focused evaluation of sports injuries using kinematics, kinetics, and electromyogram with physical and imaging to determine what is happening dynamically during sports. Future research investigating knee injuries should focus on identifying risk factors, assessing the effectiveness of surgical and nonsurgical interventions, and developing return to sport/rehabilitation protocols. The literature is focused on motion capture in adults with knee injuries.

Translesion synthesis by AMV, HIV, and MMLVreverse transcriptases using RNA templates containing inosine, guanosine, and their 8-oxo-7,8-dihydropurine derivatives.

Inosine is ubiquitous and essential in many biological processes, including RNA-editing. In addition, oxidative stress on RNA has been a topic of increasing interest due, in part, to its potential role in the development/progression of disease. In this work we probed the ability of three reverse transcriptases (RTs) to catalyze the synthesis of cDNA in the presence of RNA templates containing inosine (I), 8-oxo-7,8-dihydroinosine (8oxo-I), guanosine (G), or 8-oxo-7,8-dihydroguanosine (8-oxoG), and explored the impact that these purine derivatives have as a function of position. To this end, we used 29-mers of RNA (as template) containing the modifications at position-18 and reverse transcribed DNA using 17-mers, 18-mers, or 19-mers (as primers). Generally reactivity of the viral RTs, AMV / HIV / MMLV, towards cDNA synthesis was similar for templates containing G or I as well as for those with 8-oxoG or 8-oxoI. Notable differences are: 1) the use of 18-mers of DNA (to explore cDNA synthesis past the lesion/modification) led to inhibition of DNA elongation in cases where a G:dA wobble pair was present, while the presence of I, 8-oxoI, or 8-oxoG led to full synthesis of the corresponding cDNA, with the latter two displaying a more efficient process; 2) HIV RT is more sensitive to modified base pairs in the vicinity of cDNA synthesis; and 3) the presence of a modification two positions away from transcription initiation has an adverse impact on the overall process. Steady-state kinetics were established using AMV RT to determine substrate specificities towards canonical dNTPs (N = G, C, T, A). Overall we found evidence that RNA templates containing inosine are likely to incorporate dC > dT > > dA, where reactivity in the presence of dA was found to be pH dependent (process abolished at pH 7.3); and that the absence of the C2-exocyclic amine, as displayed with templates containing 8-oxoI, leads to increased selectivity towards incorporation of dA over dC. The data will be useful in assessing the impact that the presence of inosine and/or oxidatively generated lesions have on viral processes and adds to previous reports where I codes exclusively like G. Similar results were obtained upon comparison of AMV and MMLV RTs.