Combined Anteversion Threshold to Avoid Anterior Dislocation in Primary Total Hip Arthroplasty Performed Through the Direct Anterior Approach.

BACKGROUND: Component malposition in total hip arthroplasty (THA) can lead to dislocation, early implant failure, and revision surgery. As the surgical approach might affect the targeted combined anteversion (CA) of THA components, the present study aimed to evaluate the optimal CA threshold to avoid anterior dislocation in primary THA performed through a direct anterior approach (DAA). METHODS: A total of 1,176 THAs in 1,147 consecutive patients (men: 593, women: 554) who had an average age of 63 years (range, 24 to 91) and a mean body mass index of 29 (range, 15 to 48) were identified. Medical records were reviewed for dislocation, whereas postoperative radiographs were assessed to measure the acetabular inclination and CA using a previously validated radiographic method. RESULTS: An anterior dislocation occurred in 19 patients at an average of 40 days postoperatively. The average CA in patients who did and did not have a dislocation was 66 ± 8° and 45 ± 11°, respectively (P < .001). In 5 of 19 of the patients, a THA was performed for secondary osteoarthritis and 17 of 19 had a 28-mm femoral head. A CA ≥ 60° yielded a sensitivity of 93% and specificity of 90% for predicting an anterior dislocation in the present cohort. A CA ≥ 60° was associated with a significantly higher risk of anterior dislocation (odds ratio = 75.6; P < .001) compared to patients who had a CA<60 points. CONCLUSION: The optimal CA to avoid anterior dislocations in THA performed through the DAA should be less than 60°. LEVEL OF EVIDENCE: Cross-sectional study, Level III.

A novel method for evaluating combined component anteversion in total hip arthroplasty on cross-table lateral hip radiographs.

INTRODUCTION: Accurate measurement of combined component anteversion (CA) is important in evaluating the radiographic outcomes following total hip arthroplasty (THA). The aim of the present study was to evaluate the accuracy and reliability of a novel radiographic method in estimating CA in THA. MATERIALS AND METHODS: The radiographs and computer tomography of patients who underwent a primary THA were retrospectively reviewed, to measure the radiographic CA (CAr), defined as the angle between a line connecting the center of the femoral head to the most anterior rim of the acetabular cup and a line connecting the center of the femoral head to the base of the femoral head to allow a comparison with the CA measured on the CT (CACT). Subsequently, a computational simulation was performed to evaluate the effect of cup anteversion, inclination, stem anteversion, and leg rotation on the CAr and develop a formula that would correct the CAr according to the acetabular cup inclination based on the best-fit equation. RESULTS: In the retrospective analysis of 154 THA, the average CAr_cor, and CACT were 53 ± 11° and 54 ± 11° (p > 0.05), respectively. A strong correlation was found between CAr and CACT (r = 0.96, p < 0.001), with an average bias of - 0.5° between CAr_cor and CACT. In the computational simulation, the CAr was strongly affected by the cup anteversion, inclination, stem anteversion, and leg rotation. The formula to convert the CAr to CA_cor was: CA-cor = 1.3*Car - (17* In (Cup Inclination) - 31. CONCLUSION: The combined anteversion measurement of THA components on the lateral hip radiograph is accurate and reliable, implying that it could be routinely used postoperatively but also in patients with persistent complaints following a THA. LEVEL OF EVIDENCE: Cross-sectional study, Level III.

Superior humeral head migration might be a radiological aid in diagnosing patients with adhesive capsulitis of the shoulder.

BACKGROUND: The diagnosis of adhesive capsulitis (AC) of the shoulder might be challenging, as it is a diagnosis of exclusion and mainly based on the clinical examination. The purpose of the present study was to investigate the validity and reliability of 4 commonly reported radiological parameters suggesting a superior humeral head migration on anteroposterior (a/p) shoulder radiograph in identifying patients with AC. METHODS: The a/p shoulder radiographs of 100 patients with AC and 100 control subjects were retrospectively reviewed. A disruption of the normal scapulohumeral arch (≥2 mm), the acromiohumeral interval (AHI), the inferior glenohumeral distance (IGHD), and the upward migration index (UMI) were measured. RESULTS: A disruption of the scapulohumeral arch was observed in 80% in the AC and 20% in the control group. The mean AHI was 9.3 ± 1.3 mm and 11.0 ± 1.7 mm (P < .001), the mean IGHD was 3.9 ± 3.0 mm and 0.9 ± 1.9 mm (P < .001), and the mean UMI was 1.37 ± 0.1 and 1.44 ± 0.1 (P < .001) in patients with AC and control subjects, respectively. The scapulohumeral arch's disruption demonstrated the best test characteristics with a sensitivity and specificity of 80% in detecting patients with an AC. Patients with a disruption of the scapulohumeral arch had 16 times increased odds of having an AC. CONCLUSION: Measuring the superior humeral head migration might be a simple and clinically relevant tool in diagnosing an AC of the shoulder and could be reliably used by clinicians adjacent to the clinical examination without any additional cost. Especially a disruption of the scapulohumeral arch on the a/p shoulder radiograph should raise concerns of AC in the absence of a massive rotator cuff tear.

Distinct organ-specific up- and down-regulation of IGF-I and IGF-II mRNA in various organs of a GH-overexpressing transgenic Nile tilapia.

Several lines of GH-overexpressing fish have been produced and characterized concerning organ integrity, growth, fertility and health but few and contradictory data are available on IGF-I that mediates most effects of GH. Furthermore, nothing is known on IGF-II. Thus, the expression of both IGFs in liver and various extrahepatic sites of adult transgenic (GH-overexpressing) tilapia and age-matched wild-type fish was determined by real-time PCR. Both IGF-I and IGF-II mRNA were found in all organs investigated and were increased in gills, kidney, intestine, heart, testes, skeletal muscle and brain of the transgenics (IGF-I: 1.4-4-fold; IGF-II: 1.7-4.2-fold). Except for liver, brain and testis the increase in IGF-I mRNA was higher than that in IGF-II mRNA. In pituitary, no significant change in IGF-I or IGF-II mRNA was detected. In spleen, however, IGF-I and IGF-II mRNA were both decreased in the transgenics, IGF-I mRNA even by the 19-fold. In agreement, in situ hybridisation revealed a largely reduced number of IGF-I mRNA-containing leukocytes and macrophages when compared to wild-type. These observations may contribute to better understanding the reported impaired health of GH-transgenic fish. Growth enhancement of the transgenics may be due to the increased expression of both IGF-I and IGF-II in extrahepatic sites. It is also reasonable that the markedly enhanced expression of liver IGF-II mRNA that may mimick an early developmental stage is a further reason for increased growth.