Long-term outcome of cemented total hip arthroplasty with the Charnley-type femoral stem made of titanium alloy

Titanium - a Cementable Material for Endoarthroplasty

As materials for arthroplasty, titanium alloys exhibit the following advantages over conventional steel, cobalt chromium or chromium nickel alloys - good fatigue strength, excellent biocompatibility, low modulus of elasticity, and high corrosion resistance. The previous worse clinical outcome was most likely caused by crevice corrosion and led to reduced use. To warrant safe use, the design should be optimised (sufficient proximal diameter, proximal collar), in order to reduce unwanted deformation in the proximal part of the prosthesis. Additionally, a rough surface (Ra > 2.5 µm) should not be used. Further research in surface treatments (e. g. silicate-silane) could facilitate additional improvement.

Analysis of Bone Loss around Cemented and Biologic Prostheses after Hemiarthroplasty

Objective. To perform hemiarthroplasty (HA) on elderly patients with femoral neck fractures using cemented and biologic prostheses and then compare the bone loss around the two types of prostheses after surgery. Methods. A total of 60 patients aged over 75 years (with a mean age of 83.5 years) and suffering from femoral neck fracture (Garden types III and IV) from January 2018 to December 2020 were selected; they were randomly divided into group A ( $n=30$ , cemented prostheses) and group B ( $n=30$ , biologic prostheses) and received HA. At 1 month, 6 months, and 12 months after surgery, Harris Hip Scale (HHS) was adopted for patient evaluation, and patients’ bone mineral density (BMD) of the 7 Gruen zones around the prostheses was measured by dual-energy X-ray absorptiometry (DEXA scan). Results. Both groups achieved satisfactory results postoperatively, and the Harris scores of the hips increased gradually over time, which were better in group A than in group B. Gruen zones in group A showed a slower trend of decreasing BMD than group B, and the differences were significant at zones 2, 3, and 4 ( $P<0.05$ ). Conclusion. For elderly patients with femoral neck fractures, selecting cemented prosthesis for HA better recovers the hip function and has a low rate of bone loss around the prosthesis.

Inverted reamer technique for bone grafting of the acetabulum: technical note

Background

Socket fixation with bone grafting for dysplastic hips is technically demanding, and inadequate coverage of the socket may cause poor results in patients with severely dysplastic hips. An accurate technique to form a bone graft to fit into the defect is necessary. We aim to introduce the simple method of bone grafting, “inverted reamer technique” in cemented total hip arthroplasty (cTHA).

Methods

After acetabular preparation with a normal acetabular reamer, the bone graft was prepared from the resected femoral head with the inverted reamer. The graft can be press-fit into the defect of the acetabulum with good compatibility through this method. Then, the bone graft was fixed with 1–3 screws and the socket was implanted with bone cement.

Results

The “inverted reamer technique” can easily and automatically create a well-fit graft. This method is simple and technically less demanding; it can be performed by every surgeon, including trainee and inexperienced surgeons.

Conclusion

This method can improve the outcome of cTHA for dysplastic hips by preserving bone stock and increasing bone coverage of the socket implanted in the anatomic position.

The bikini incision anterior cemented total hip arthroplasty: Assessment of radiological and clinical outcomes - A mid-term review

INTRODUCTION

There has been an increased interest in minimally invasive direct anterior approach total hip arthroplasty (THA) to provide greater patient satisfaction, improve pain relief, and reduce the duration of hospitalisation. A direct anterior approach hybrid cemented THA, utilising a bikini line incision, can be technically challenging. We aimed to undertake radiological analysis of femoral stem cementation, clinical outcomes, and component survivorship.

METHODS

Over a 5-year period, 215 primary elective bikini anterior THA conducted by a single surgeon were included. All procedures were performed using a cemented collarless polished stem. The operation was performed on a standard operating table. Patients undergoing posterior approach, revision procedures, and fractured neck of femurs were excluded. Post-operative radiographs were analysed for femoral cementation quality using the Barrack grading system. Harris hip scores (HHS) were determined at 6 weeks, 12 weeks, annually thereafter and the difference in HHS was noted.

RESULTS

In total, 215 anterior bikini THA (R = 101, L = 114) were performed in 199 patients (M = 89, F = 110) with a mean age of 77 and mean follow up of 2.9 years (range = 0.5-5). Radiographic analysis of femoral cementation showed 189 femoral stems (88%) were either Barrack A or B cementation grade, suggesting optimal cementation. Lucency in the cement-bone interface occurred mainly in Gruen Zone 1 (43%) and Zone 13(46.9%). At the most recent follow-up (mean 2.9 years), component survivorship was at 99.54% (stem). Significant improvement was noted in Harris hip scores at final follow-up (from 54 preoperatively to 92.7 at 2.9 years postoperatively).

CONCLUSION

Our results suggest that a bikini incision direct anterior approach for total hip arthroplasty can be safely employed to perform cemented femoral stems on a standard operating table.