Functional Outcomes of Anterior-Based Muscle Sparing Approach Compared to Direct Lateral Approach for Total HIP Arthroplasty Following Acute Femoral Neck Fractures

Introduction

Total hip arthroplasty (THA) performed for femoral neck fractures (FNFs) is becoming a more frequent treatment in the active elderly population. Since there is limited research available presenting clinical outcomes after THA using the anterior-based muscle sparing (ABMS) approach, the aim of this study was to compare this surgical approach to the direct lateral (DL) approach in patients treated by THA for FNFs.

Materials and Methods

We retrospectively reviewed the data prospectively collected as a part of our "Hip Fracture Unit" and included 163 patients who underwent THA from January 2016 to January 2019 for acute displaced FNFs.

Results

A total of 132 patients who completed a minimum 2-years follow up (69 in the ABMS group and 63 in DL group) were included. The ABMS group demonstrated significantly shorter time to reach milestone for hospital discharge (1.5 Days vs 2.1 days, P = .018), while no statistically significant differences were detected in peri-operative complications. At 3 months, the timed up and go test, the Harris Hip Score (HHS) and the Oxford ip Score (OHS) were significantly better (P = .024, .032 and .034, respectively) in the ABMS group compared to the DL group. No differences were found in functional outcomes (HHS and OHS) nor in complication rate at 6, 12 and 24 months.

Discussion

This is one of the first studies to analyze functional results of THA performed for FNFs through an ABMS approach. Results are in line with those already present in the Literature.

Conclusion

ABMS approach allows earlier mobilization and better early functional outcomes, compared to DL approach, in patients undergoing THA for acute displaced FNF. No differences are found after 6 months in functional results and complications rate.

The lesser trochanter "Sling fixation technique" in proximal intramedullary nailing of unstable intertrochanteric fractures: A polymer-based cerclage wiring

Introduction

Lesser trochanter (LT) fixation to restore the continuity of the posteromedial fragment using a cerclage wire has been reported to provide a more stable reduction in the treatment of unstable femoral neck fractures with LT involvement. However, LT fixation is not commonly performed due to the complications associated with the traditional monofilament cerclage metal wires. In this study, we investigate the clinical and radiological outcomes of a new technique for LT fixation in conjunction with Intramedullary (IM) fixation with nail and screws when compared to isolated IM fixation. The Sling Fixation Technique involves a new wiring technique and the use of a polymer-based cerclage cable characterized by iso-elastic properties that is hypothesized to provide better clinical and radiographic outcomes.

Patients and methods

This prospective observational study included 30 patients who underwent proximal IM nailing from July 2019 to April 2020. Thirty consecutive patients (30) were assigned to 2 different treatment groups. Fifteen (15) patients were treated with the IM Nailing and Sling Fixation Technique and 15 with IM nailing only. Patients were comparable for demographic features, fracture pattern, age, gender and associated medical comorbidities. Clinical outcomes were analyzed in terms of time needed to achieve complete weight bearing, Harris hip score (HHS), Barthel Index (BI) and Radiographic Union Scale for Hip (RUSH). The follow-up period was one year.

Results

Time for fracture healing and to achieve weight-bearing in the "Sling" group were shown to be significantly shorter than in the IM group. The Sling group showed furthermore better HHS, BI and RUSH scores when compared to the IM group at 1, 3, 6, and 12 months from the surgery. No complications such as wiring breakage, cut-outs, breakage or pullout of the fixation screws were observed; one case of heterotrophic ossification was reported.

Conclusion

In cases of unstable intertrochanteric fractures of the proximal femur with lesser trochanter involvement, the Sling fixation technique using an isoelastic polymer-based wire showed superior results in terms of stability and consequently better clinical and radiographic outcomes than IM nailing only.

Immunohistochemical localization of nNOS in the head kidney of larval and juvenile rainbow trout, Oncorhynchus mykiss

The aim of this investigation was to assess whether in teleosts, as in mammals, nitric oxide (NO) is involved in the regulation of cellular activity in the adrenal homolog. Larval and juvenile stages of the rainbow trout, Oncorhynchus mykiss, were used, in which the adrenal homolog consists of chromaffin adrenergic and interrenal steroidogenic cells localized mainly in the head kidney where there are also ganglion cells and nerve fibres that innervate the gland. In 12-month-old juveniles, the immunohistochemical reaction for neuronal nitric oxide synthase (nNOS), which catalyzes the synthesis of NO, revealed the presence of this enzyme in some nerve fibres and ganglion cells and only rarely in chromaffin cells. The latter are identified by the immunohistochemical reaction for tyrosine hydroxylase (TH) and phenylethanolamine-N-methyltransferase (PNMT). In larvae at 27 days postfertilization, numerous cells dispersed in the head kidney are nNOS positive, whereas the TH and PNMT positive cells are very rare. At hatching (31 days postfertilization), the positivity for nNOS in the cells of the head kidney disappears and reappears at 60 days posthatching in some nerve cells and fibres. These results suggest an involvement of NO in the regulation of adrenal function as in mammals and the nature of nNOS positive cells present in the head kidney of larvae of 27 days is discussed.

Ultrastructural and histochemical study on the interrenal cells of the male stickleback (Gasterosteus aculeatus, Teleostea), in relation to the reproductive annual cycle

The steroidogenic interrenal cells in the adrenal homologue of the male stickleback (Gasterosteus aculeatus) were studied in relation to the reproductive cycle by means of histological and ultrastructural observations, and using histochemical methods for the localisation of 3beta-hydroxysteroid dehydrogenase (3betaHSD) and 17beta-hydroxysteroid dehydrogenase (17betaHSD). To determine the various stages of the reproductive cycle, the testes were also examined by histological and histochemical methods (3betaHSD). The results indicate that in this teleost the interrenal cells can undergo a cycle in which phases characterised by different cytological aspects are observed. During this cycle there is a renewal of organelles, in particular mitochondria and SER. Periodic degenerative processes are also found. Organelle cytology showed that the cell cycle has at least 3 different aspects during the year. An analogy with some cytological aspects of the adrenal zonation in mammals is possible. It is postulated that the interrenal gland activity could substitute or supplement androgen production by the testes.

Immunohistochemical and ultrastructural evidence of adrenal chromaffin cell subtypes in sea bass Dicentrarchus labrax (L.)

Histology demonstrated chromaffin cells in the head kidney and opisthonephros of the sea bass. Immunohistochemistry showed the catecholamine-synthesizing enzymes tyrosine hydroxylase and dopamine beta-hydroxylase in these cells. Phenlethanolamine N-methyltransferase was detected in a fraction of the chromaffin cells in the head kidney (59%) and in the opisthonephros (54%). Distinct noradrenaline- and adrenaline-synthesizing cells are therefore suggested. Ultrastructural analysis confirmed the existence of two main chromaffin cell types, distinguished by different types of the secretory granules. Cells that contain vesicles with a round, electron-dense core were interpreted as noradrenaline cells, while cells with electron-lucent vesicles were identified as adrenaline cells. The ultrastructure of these chromaffin cell subtypes does not differ in the head kidney and opisthonephros. A minor population of chromaffin cells was identified, which typically show smaller vesicles with an electron-dense core. This population may account for a limited number of not fully differentiated chromaffin cells.

Chick gonadogenesis following early surgical bursectomy. II. Ultrastructural data on the embryonic left and right female gonads

We examined the ultrastructural characteristics of the medullary steroidogenic cells in left and right female gonads of surgically bursectomized chick embryos killed on the 17th day of incubation. The steroidogenic cells of the bursectomized embryos have a more developed system of cisternae in the smooth endoplasmic reticulum than controls, and their mitochondria show some alterations in the density of the matrix and in the shape of the cristae. On the basis of these results, an enhancement of the steroidogenic activity in both gonads is suggested.

Cytological and biochemical studies on chromaffin cells in the head kidney of Gasterosteus aculeatus (Teleostei, Gasterosteidae)

Adrenal chromaffin cells in the head kidney of the stickleback Gasterosteus aculeatus were examined by ultrastructural analysis and determination, by HPLC, of the catecholamine content (adrenaline, noradrenaline, and dopamine). Chromaffin cells are characterized by the presence of membrane-bound vesicles and two cell types were identified: (i) those with vesicles containing a strongly electron-dense core; and (ii) those with vesicles that are completely electron lucent or containing smaller and less-dense granules. HPLC analysis revealed the presence of adrenaline and noradrenaline in both right and left head kidneys. Dopamine was not detected. Cytological and biochemical data suggest that the cells with electron-dense granules contain noradrenaline and those with electron-lucent vesicles contain adrenaline.

Chick gonadogenesis following early surgical bursectomy. I. Histological, morphometric and histochemical data on the embryonic left ovary

Left ovaries of bursectomized chick embryos were examined on the 17th day of incubation in comparison to normal and sham-operated controls, by histological and histochemical observations. The results show that in bursectomized embryos the cortex appears irregularly developed, with a significant decrease in the mean thickness and in the percentage of the secondary sex cords in the total cortical area. Furthermore, the germinal epithelium appears thicker and the subcortical medulla and the tunica albuginea more compact. The greater activity of the enzyme delta 5-3 beta-hydroxysteroid dehydrogenase (delta (5)3 beta HSD) found in ovaries of bursectomized embryos (histochemical method) could be related to an endocrine dismetabolism affecting the cortical development. On the basis of these results and those of other authors, some hypotheses are advanced. In particular, an action of the bursal factor on GTH receptors could be the factor responsible of the enhanced steroidogenic activity altering the hormonal environment.

Ultrastructural localization of acid phosphatase in germ cells of chick embryo left ovary

The ultracytochemical localization of acid phosphatase was studied in oogonia and oocytes of the chick embryo left ovary. The reaction products are evident in lysosomes of various types and, in some cells, in the GERL as well. Furthermore, from the onset of the meiotic prophase, the enzymatic reaction also appears in the rough endoplasmic reticulum. Non-incubated sections of the same stages were observed, with the aim of identifying and describing the structure of the organelles, in particular lysosomes which appeared positive in incubated sections. The significance of the presence of the enzyme is discussed.