High risk of positive Trendelenburg test after using the direct lateral approach to the hip compared with the anterolateral approach: a single-centre, randomized trial in patients with femoral neck fracture.

AIMS: The aim of this randomized trial was to compare the functional outcome of two different surgical approaches to the hip in patients with a femoral neck fracture treated with a hemiarthroplasty. PATIENTS AND METHODS: A total of 150 patients who were treated between February 2014 and July 2017 were included. Patients were allocated to undergo hemiarthroplasty using either an anterolateral or a direct lateral approach, and were followed for 12 months. The mean age of the patients was 81 years (69 to 90), and 109 were women (73%). Functional outcome measures, assessed by a physiotherapist blinded to allocation, and patient-reported outcome measures (PROMs) were collected postoperatively at three and 12 months. RESULTS: A total of 11 patients in the direct lateral group had a positive Trendelenburg test at one year compared with one patient in the anterolateral group (11/55 (20%) vs 1/55 (1.8%), relative risk (RR) 11.1; p = 0.004). Patients with a positive Trendelenburg test reported significantly worse Hip Disability Osteoarthritis Outcome Scores (HOOS) compared with patients with a negative Trendelenburg test. Further outcome measures showed few statistically significant differences between the groups. CONCLUSION: The direct lateral approach in patients with a femoral neck fracture appears to be associated with more positive Trendelenburg tests than the anterolateral approach, indicating a poor clinical outcome. Cite this article: Bone Joint J 2019;101-B:793-799.

Biomarkers of muscle damage increased in anterolateral compared to direct lateral approach to the hip in hemiarthroplasty: no correlation with clinical outcome : Short-term analysis of secondary outcomes from a randomized clinical trial in patients with a displaced femoral neck fracture.

In this study, we found elevated levels of serum CK in the anterolateral approach to the hip compared to the direct lateral approach in patients with a displaced femoral neck fracture. No correlation was found between levels of CK and functional outcomes. INTRODUCTION: To compare increase in serum creatine kinase (CK) and its association with functional outcome between the muscle-sparing anterolateral approach and the direct lateral approach to the hip in patients with displaced femoral neck fracture (FNF). METHODS: In this randomized trial, we enrolled eligible patients between 70 and 90 years of age with FNF. Patients were allocated to an uncemented hemiarthroplasty inserted through a direct lateral or an anterolateral approach. The primary endpoints were pain and patient satisfaction assessed by the Visual Analogue Scale (VAS). Among secondary endpoints was increase in CK at 24 and 48 h compared to baseline and its association with surgical parameters, Timed up and Go Test (TUG), Harris Hip Score (HHS), and the presence of a Trendelenburg sign using correlation analysis. This paper reports on increase in serum CK and its association with functional outcome. RESULTS: At 24 h, there was a mean increase from baseline in total CK of 228 U/L (95% CI 187 to 269; P < 0.001). There was a difference between groups at 24 h in CK increase with higher levels in the anterolateral group (mean difference 80 U/L; 95% CI - 0.5 to 162; P = 0.05). Likewise, at 48 h, there was a mean difference of 117 U/L (95% CI 22 to 212; P = 0.01). No correlation was found between CK values and functional assessments. CONCLUSIONS: Compared with the direct lateral approach, the anterolateral approach yielded higher levels of postoperative CK. However, there was no correlation between levels of CK and functional outcome. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02028468.

Benzalkonium chloride interferes with energy production, secretion and morphology in human blood platelets.

Benzalkonium chloride (BC) is a bactericidal compound used as a topical antiseptic and as a preservative in various products for local treatment, e.g., eye and nose drops. BC is toxic to human cells, including those of the respiratory mucosa. Few studies have, however, focused on what cellular functions BC interferes with. The effects of BC were studied on washed human blood platelets in vitro . Cellular energy production as well as secretion were studied. Incubation of platelets with BC resulted in rapid swelling and toxic morphological changes. After incubation with BC oxidation of [1-14C] palmitate was inhibited, and both lactate dehydrogenase and endogenous serotonin were spontaneously released. Thrombin-induced secretion of serotonin was strongly reduced after BC exposure. Histological changes with increased size, spherical form, decreased numbers of pseudopodia, loss of an intact continuous tubulus system and reduced number of granules were found by scanning and transmission electron microscopy. It is concluded that the toxic effects of BC are because of interference with membrane function and energy production.

The effects of topical nasal steroids on rat respiratory mucosa in vivo, with special reference to benzalkonium chloride.

Fifty rats were treated with topical nasal steroids with and without the preservative benzalkonium chloride in their right nostril twice daily for 21 days, while the left nostrils were exposed to 0.9% NaCl. By cutting the noses serially in frontal sections, the structure of the mucosal lining of all parts of the nose could be investigated. Areas with squamous cell metaplasia were observed in all nostrils exposed to topical steroids containing benzalkonium chloride. Such alterations were not observed in any nasal cavities exposed to the topical nasal steroid without the preservative or to 0.9% NaCl. In conclusion, benzalkonium chloride appears to be potentially toxic to the mucosa in vivo.

Effects of topical nasal steroids on human respiratory mucosa and human granulocytes in vitro.

Human respiratory mucosa and human granulocytes were exposed to topical nasal steroids in vitro. The preparations containing benzalkonium chloride and benzalkonium chloride alone destroyed the mucosa within 10 days. The same preparations also inhibited human neutrophil actin polymerization, degranulation and oxidative burst in vitro in a time and concentration dependent manner. Preparations without benzalkonium chloride, as well as the steroid compounds themselves, did not have these effects. It is concluded that benzalkonium chloride has toxic effects on human respiratory mucosa and human neutrophils in vitro.

The effect of a benzalkonium chloride-containing nasal spray on human respiratory mucosa in vitro as a function of concentration and time of action.

Human respiratory mucosa was exposed to oxymetazoline nasal spray in varying concentrations and for varying periods of time in vitro. The drug destroyed the tissue in a concentration- and time-dependent manner. In the experiments with various concentrations of the spray, some tissue fragments retained their viability throughout the experiment. This number increased parallel to a decrease in concentrations of the test substance. All the tissue fragments exposed to undiluted nose spray underwent severe destructive alterations during the exposure period. These alterations appeared first and were most extensive in those exposed for the longest periods of time. It has previously been demonstrated that the toxic effect of oxymetazoline nasal spray in vitro is probably due to the preservative benzalkonium chloride. The apparent lack of consistency between the toxic effects of benzalkonium chloride in vitro and in vivo is discussed, with special reference to protective systems absent in vitro but present in vivo.

The effect of decongestive nosedrops on human respiratory mucosa in vitro.

The aim of this study was to investigate the morphological effects of decongestive drops and sprays on human respiratory mucosa in vitro. Precultured fragments of adenoid tissue in a specially designed tissue culture system were exposed to decongestive preparations for 10 minutes once a day for 10 days. Tissue exposed to preparations preserved with benzalkonium chloride and tissue exposed to benzalkonium chloride alone underwent severe morphological alterations. Unpreserved decongestive substances did not have this effect. Benzalkonium chloride is a well-documented toxic substance in several respects. Supported by previous studies, it may seem unfortunate to use it as an additive in decongestive preparations.