Influence of age on clinical outcomes of three-dimensional transfer of the tibial tuberosity for patellar instability with patella alta

Purpose

To evaluate the clinical outcomes of three-dimensional (3D) transfer of the tibial tuberosity for patellar instability with patella alta, with a focus on the influence of age at initial surgery.

Methods

Three-dimensional surgery was performed on 28 knees with a mean follow-up of 46 months. Patients were separated into three groups based on the age at initial surgery: group A, 10 knees and an average age of 16.3 ± 1.8 (14–19) years; group B, 10 knees and an average age of 22.1 ± 2.5 (20–28) years; and group C, eight knees and an average age of 44.0 ± 2.2 (40–46) years. Patellofemoral geometry improvement focused on patella alta by determining the Insall–Salvati ratio and Caton–Deschamps index, rotational malalignment by measuring the tibial tubercle–trochlear groove (TT–TG) distance, and lateral patellar subluxation by measuring the patellar tilt. Clinical outcomes were evaluated by the Lysholm and Kujala scores, which were compared before and after surgery. Cartilage degeneration was evaluated by the International Cartilage Repair Society grading system at initial arthroscopy.

Results

The patellar height, TT–TG, and patellar tilt significantly improved in all groups postoperatively (p < 0.05). The Lysholm and Kujala scores also significantly improved postoperatively; however, both scores were lower in group C than in the other groups (p < 0.05). Particularly, pain scores were more severe in group C than in the other groups, and the severity of cartilage degeneration correlated with the pain scores (p < 0.05). Cartilage damage differed significantly between the groups at initial arthroscopy; particularly, group C included grades III and IV cartilage degeneration (p < 0.05).

Conclusions

Age at initial surgery may be the predicting factor for poor clinical outcomes of 3D transfer surgery. The clinical outcome may depend on the age at surgery, which correlated with cartilage damage; thus, surgeons should be given this information when patients are considered undergoing patella surgery.

Level of evidence

Therapeutic case series, Level IV.

     

Hydrogen sulfide regulates Na+/H+ exchanger activity via stimulation of phosphoinositide 3-kinase/Akt and protein kinase G pathways

Intracellular pH (pH(i)) is an important endogenous modulator of cardiac function. Inhibition of Na(+)/H(+) exchanger-1 (NHE-1) protects the heart by preventing Ca(2+) overload during ischemia/reperfusion. Hydrogen sulfide (H(2)S) has been reported to produce cardioprotection. The present study was designed to investigate the pH regulatory effect of H(2)S in rat cardiac myocytes and evaluate its contribution to cardioprotection. It was found that sodium hydrosulfide (NaHS), at a concentration range of 10 to 1000 μM, produced sustained decreases in pH(i) in the rat myocytes in a concentration-dependent manner. NaHS also abolished the intracellular alkalinization caused by trans-(±)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]benzeneacetamide methane-sulfonate hydrate (U50,488H), which activates NHEs. Moreover, when measured with an NHCl(4) prepulse method, NaHS was found to significantly suppress NHE-1 activity. Both NaHS and cariporide or [5-(2-methyl-5-fluorophenyl)furan-2-ylcarbonyl]guanidine (KR-32568), two NHE inhibitors, protected the myocytes against ischemia/reperfusion injury. However, coadministration of NaHS with KR-32568 did not produce any synergistic effect. Functional study showed that perfusion with NaHS significantly improved postischemic contractile function in isolated rat hearts subjected to ischemia/reperfusion. Blockade of phosphoinositide 3-kinase (PI3K) with 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002), Akt with Akt VIII, or protein kinase G (PKG) with (9S,10R,12R)-2,3,9,10,11,12-hexahydro-10-methoxy-2,9-dimethyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]]enzodiazocine-10-carboxylic acid, methyl ester (KT5823) significantly attenuated NaHS-suppressed NHE-1 activity and/or NaHS-induced cardioprotection. Although KT5823 failed to affect NaHS-induced Akt phosphorylation, Akt inhibitor did attenuate NaHS-stimulated PKG activity. In conclusion, this work demonstrated for the first time that H(2)S produced cardioprotection via the suppression of NHE-1 activity involving a PI3K/Akt/PKG-dependent mechanism.     

Predictors of risk of alcohol-exposed pregnancies among women in an urban and a rural area of South Africa

The study sought to determine the prevalence and predictors of being at risk of an alcohol-exposed pregnancy (AEP) among women of child-bearing age in an urban and rural location in South Africa. We conducted a cross-sectional household survey of 1018 women aged 18–44 years in one urban (n = 606) and one rural (n = 412) site. The women were interviewed using a structured questionnaire. We defined the primary dependent variable, being at risk of having an AEP, as current alcohol use, not being pregnant, being fertile, and no effective use of contraceptives. The independent variables included demographic, substance use, health perceptions, psycho-social, and partner characteristics. The rural women (21.84%) were more likely than their urban counterparts (11.22%) to be at risk of an AEP. In multiple logistic regression analyses, significant predictors of being in the “at risk” group for the urban women were (a) being ‘white’ as opposed to ‘black/African’, and being ‘coloured’ as opposed to ‘black/African’; and (b) current smoking. For the rural women, significant risk factors were (a) current smoking and (b) early onset of alcohol use. The significant protective factors were (a) education; (b) knowledge about Fetal Alcohol Syndrome; (c) parity. Use of stricter alcohol use criteria (i.e., three or more drinks and five or more drinks per sitting) in the definition of risk of an AEP yielded slightly different patterns of significant predictors. The results revealed high levels of risk of an alcohol-exposed pregnancy, especially amongst the rural women, and a need for location-specific prevention programmes. The high burden of AEP in South Africa calls for the establishment of national AEP prevention strategies and programmes as a matter of urgency.     

Changes in the renin angiotensin system during the development of colorectal cancer liver metastases

Background  

Blockade of the renin angiotensin system (RAS) via angiotensin I converting enzyme (ACE) inhibition reduces growth of colorectal cancer (CRC) liver metastases in a mouse model. In this work we defined the expression of the various components of the RAS in both tumor and liver during the progression of this disease.     

Outcomes of Roux-en-Y gastric bypass and laparoscopic adjustable gastric banding

AIM:To evaluate weight loss and surgical outcomes of Roux-en-Y gastric bypass(RYGB)and laparoscopic adjustable gastric band(LAGB).METHODS:Data relating to changes in body mass index(BMI)and procedural complications after RYGB(1995-2009;n=609;116M:493F;42.4±0.4 years)or LAGB(2004-2009;n=686;131M:555F;37.2±0.4years)were extracted from prospective databases.RESULTS:Pre-operative BMI was higher in RYGB than LAGB patients(46.8±7.1 kg/m2vs 40.4±4.2 kg/m2,P<001);more patients with BMI<35 kg/m2underwent LAGB than RYGB(17.1%vs 4.1%,P<0.0001).BMI decrease was greater after RYGB.There were direct relationships between weight loss and pre-operative BMI(P<0.001).Although there was no difference in weight loss between genders during the first 3-year post-surgery,male LAGB patients had greater BMI reduction than females(-8.2±4.3 kg/m2vs-3.9±1.9kg/m2,P=0.02).Peri-operative complications occurred more frequently following RYGB than LAGB(8.0%vs0.5%,P<0.001);majority related to wound infection.LAGB had more long-term complications requiring corrective procedures than RYGB(8.9%vs 2.1%,P<0.001).Conversion to RYGB resulted in greater BMI reduction(-9.5±3.8 kg/m2)compared to removal and replacement of the band(-6.0±3.0 kg/m2).Twelve months post-surgery,fasting glucose,total cholesterol and low density lipoprotein levels were significantly lower with the magnitude of reduction greater in RYGB patients.CONCLUSION:RYGB produces substantially greater weight loss than LAGB.Whilst peri-operative complications are greater after RYGB,long-term complication rate is higher following LAGB.     

Social Support and the Mediating Roles of Alcohol Use and Adherence Self-Efficacy on Antiretroviral Therapy (ART) Adherence Among ART Recipients in Gauteng,South Africa

We sought to (a) replicate and (b) extend (via the addition of alcohol use) Cha et al.’s cross-sectional multi-component model of ART adherence on the relationship between social support, depression, self-efficacy beliefs, and antiretroviral therapy (ART) adherence, among HIV patients in Tshwane, South Africa. Using purposive sampling, 304 male and female ART recipients were recruited. ART adherence was assessed using three manifest indicators: total adherence ratio, the CASE adherence index and 1-month adherence measure. Data were analysed using structural equation modeling. In our replicated model, social support had both direct and indirect relationships with ART adherence, and inclusion of alcohol use improved prediction of ART adherence. Direct and indirect effects of alcohol use on ART adherence emerged: adherence self-efficacy beliefs partially mediated the latter path. Findings highlight the importance of integrating into ART promotion interventions, the reduction of alcohol use, provision of social support, and enhancement of adherence self-efficacy beliefs.