Comparison of Surgical Outcomes Between Standard and Elevated-Rim Highly Cross-Linked Polyethylene Acetabular Liners in Primary Total Hip Arthroplasty With Minimum 15-Year Follow-Up: Single-Center, Retrospective Cohort Study

Metal-on-crosslinked polyethylene in total hip arthroplasty - an excellent combination at fifteen to twenty years of follow-up

PURPOSE

Cross-linked polyethylene (PE) has been used with great clinical success in total hip arthroplasty (THA) since its debut in the late 1990's. However, reports regarding this bearing couple near the end of its second decade of service are still scant. The aim of this study was to first determine the long term clinical and radiological results and second Investigate what factors affect wear rates using a metal-on-crosslinked PE bearing articulation.

METHODS

55 THAs using a single brand of cross-linked liner, cementless cup and 28 mm hip ball were performed in 44 patients. Age, sex, Charlson Comorbidity Index (CCI) and need for revision surgery were recorded. Linear and volumetric wear was determined using the Martell method.

RESULTS

Mean age at operation was 51.2 (29-73 ± 12.1) years. Mean duration of follow-up was 16.9 years (range 15.0-20.1 ± 1.1 years). Osteolysis was not present in the latest follow-up radiographs. Median linear and volumetric wear rate was 0.038 mm/year (95% CI 0.032-0.047) and 7.115mm3/year (95% CI 6.92-17.25) respectively. Acetabular component position was not found to be related to both linear and volumetric wear. No significant difference was found in the linear and volumetric wear rates of thinner and thicker liners (8 mm or below and > 8 mm) (p = 0.849 and p = 0.64 respectively).

CONCLUSION

Metal-on-crosslinked PE is associated with low linear and volumetric wear rates which has virtually obviated osteolysis and has translated to excellent survivorship even at long term follow up. In-vivo oxidation does not appear to be of clinical concern at this point.

Efficacy of Pericapsular Nerve Group Block for Pain Reduction and Opioid Consumption after Total Hip Arthroplasty: A Meta-Analysis of Randomized Controlled Trials

The aim of this study was to conduct a meta-analysis of randomized controlled trials (RCTs) for comparison of the effectiveness of pericapsular nerve group (PENG) block with that of other analgesic techniques for reduction of postoperative pain and consumption of opioids after total hip arthroplasty (THA). A search of records in the PubMed, Embase, and Cochrane Library, and ClinicalTrials.gov databases was conducted in order to identify studies comparing the effect of the PENG block with that of other analgesics on reduction of postoperative pain and consumption of opioids after THA. Determination of eligibility was based on the PICOS (participants, intervention, comparator, outcomes, and study design) criteria as follows: (1) Participants: patients who underwent THA. (2) Intervention: patients who received a PENG block for management of postoperative pain. (3) Comparator: patients who received other analgesics. (4) Outcomes: numerical rating scale (NRS) score and opioid consumption during different periods. (5) Study design: clinical RCTs. Five RCTs were finally included in the current meta-analysis. Significantly lower postoperative opioid consumption at 24 hours after THA was observed in the group of patients who received the PENG block compared with the control group (standard mean difference=-0.36, 95% confidence interval -0.64 to -0.08). However, no significant reduction in NRS score at 12, 24, and 48 hours after surgery and opioid consumption at 48 hours after THA was observed. The PENG block showed better results for opioid consumption at 24 hours after THA compared with other analgesics.

Long-term outcome of primary total hip arthroplasty with cementless bioactive glass ceramic bottom-coated implants and highly cross-linked polyethylene: A minimum 10-year analysis

BACKGROUND

Cementless glass ceramics containing apatite and wollastonite (AW-GC) bottom-coated titanium hip implants were developed; early excellent clinical and radiographic results have been reported previously. This study aimed to investigate the long-term clinical and radiographic outcomes in detail, and the wear rate of HXLPE.

METHODS

We retrospectively evaluated 99 patients (117 hips) between November 2001 and December 2007. The survival rate was estimated using the Kaplan-Meier method. Hip joint function was evaluated using the Japanese Orthopaedic Association (JOA) score. The extent of radiographic signs was determined from the radiographs performed at the last follow-up. Polyethylene wear was measured using Martell's Hip Analysis Suite. We assessed the possible factors affecting the steady-state linear wear rate.

RESULTS

The mean follow-up period was 14.8 ± 2.1 (10-18.6) years. The mean JOA score improved to 88.7 ± 9.4 (59-100) at the final follow-up from 47.8 ± 12.5 (17-76) before surgery. The overall survival rate with the end point of all-cause revision and wear-related revision was 99% and 100% respectively. There was no osteolysis or loosening of either the acetabular or femoral component. All hips were classified as having bone ingrowth fixation. The mean steady-state wear rate was 0.008 ± 0.025 mm/year. We found no significant correlation between the wear rate and age, body weight, body mass index, cup inclination and femoral head size.

CONCLUSION

The combination of AW-GC bottom-coated implants and HXLPE showed excellent implant survival and wear resistance for 15 years.

Wear resistance of first-generation highly cross-linked annealed polyethylene in cementless total hip arthroplasty is maintained 20 years after surgery

AIMS

The aim of this study was to evaluate the performance of first-generation annealed highly cross-linked polyethylene (HXLPE) in cementless total hip arthroplasty (THA).

METHODS

We retrospectively evaluated 29 patients (35 hips) who underwent THA between December 2000 and February 2002. The survival rate was estimated using the Kaplan-Meier method. Hip joint function was evaluated using the Japanese Orthopaedic Association (JOA) score. Two-dimensional polyethylene wear was estimated using Martell's Hip Analysis Suite. We calculated the wear rates between years 1 and 5, 5 and 10, 10 and 15, and 15 and final follow-up.

RESULTS

The mean follow-up period was 19.1 years (SD 0.6; 17.3 to 20.1). The 19-year overall survival rate with the end point of all-cause revision was 97.0% (95% confidence interval (CI) 91 to 100). The mean JOA score improved from 43.2 (SD 10.6; 30 to 76) before surgery to 90.2 (SD 6.4; 76 to 98) at the final follow-up (p < 0.001). There was no osteolysis or loosening of the acetabular or femoral components. The overall steady-state wear rate was 0.013 mm/year (SD 0.012). There was no hip with a steady-state wear rate of > 0.1 mm/year. There was no significant difference in wear rates for each period. We found no significant correlation between the wear rate and age, body weight, BMI, or cup inclination.

CONCLUSION

First-generation annealed HXLPE shows excellent wear resistance and no acceleration of wear for approximately 20 years, with low all-cause revision rates. Cite this article: Bone Joint J 2022;104-B(2):200-205.

Use of elevated liners in primary total hip arthroplasty: a systematic review of the literature

PURPOSE

Instability remains one of the most frequent complications requiring revision surgery after primary total hip arthroplasty (THA). Elevated liners are often utilized to reduce the risk of dislocation; however, the literature is inconclusive, with no systematic reviews summarizing the data. Thus, this systematic review aimed to establish a consensus for the efficacy of elevated liners in primary THA by determining rates of overall revision and revision specifically for recurrent dislocation.

MATERIALS AND METHODS

This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eligible randomized-controlled trials and observational studies reporting on the use of elevated liners in primary total hip arthroplasty were identified through May 2020. A random effects model meta-analysis was conducted, and the I² statistic was used to assess for heterogeneity.

RESULTS

Eight studies met inclusion criteria, and overall, 26,507 patients undergoing primary THA with use of an elevated liner were included. In aggregate, the most common cause of revision was recurrent hip dislocation (1.3%, N = 82/6,267) followed by joint infection (1.2%, N = 45/3,772) and acetabular loosening (0.3%, N = 10/3,772). Notably, elevated liners were associated with a lower risk of revision for recurrent dislocation compared to neutral liners (HR: 0.74; 95% CI: 0.55-1.00; p = 0.048).

CONCLUSION

This review found that after primary THA with the use of elevated liners, hip dislocation and prosthetic joint infection continued to be the most frequent reasons for revision surgery. However, elevated liners had a lower risk of revision for recurrent dislocation compared to neutral liners.

Unstable total hip replacement: why? Clinical and radiological aspects

INTRODUCTION

Dislocation after total hip arthroplasty (THA) is the most common cause of revision hip surgery in the United States, ahead of aseptic loosening and infection, and is responsible for considerable economic cost related to frequent readmission and/or revision surgery. The aim of this article is to identify the clinical and radiological factors related to the unstable total hip replacement.

METHODS

We performed a literature search to assess current strategies to define clinical and radiological characteristics of dislocation after primary THA using the PubMed platform. The characteristics related to THA instability were divided into patient related factors, implant related factors and surgeon experience.

RESULTS

Patient-related factors for instability identified are: age; inflammatory joint disease; prior hip surgery; preoperative diagnosis; comorbidity; ASA score; presence of spino-pelvic abnormality; and neurological disability. Gender, simultaneous bilateral THA and restrictive postoperative precautions do not influence rate of THA dislocation. Implant related factors identified are: surgical approach; component malposition; femoral head size; and the use of dual-mobility or constrained solution. Surgeon experience also reduces the rate of dislocation.

DISCUSSION

Dislocation is a major complication of THAs, and causes include patient-derived factors, surgical factors, or both. It is imperative to determine the cause of the instability via a complete patient and radiographic evaluation and to adjust the reconstruction strategy accordingly.

Recent update on crosslinked polyethylene in total hip arthroplasty

More than two decades after their clinical introduction, crosslinked polyethylenes (XLPE) have been widely adopted. Though concerns were initially raised regarding oxidation and brittleness, on a large scale, the first generation of XLPE continues to be highly effective 15 years after the surgery, even in a young and active population. Remelted XLPE might display lower wear rates than annealed XLPE. Second generation XLPEs, not only including sequentially irradiated and annealed but also associated with antioxidants, demonstrate encouraging short- to mid-term results. Registry data support clinical trial reports. Even in less favorable settings (lipped liners, dual mobility cups, revision surgery, hip resurfacing) results are promising. However, failures (fractures) have already been described. Therefore, a high level of surveillance remains crucial.