Comparison of Clinical Efficacy Between Modular Cementless Stem Prostheses and Coated Cementless Long-Stem Prostheses on Bone Defect in Hip Revision Arthroplasty

Does size matter? Outcomes following revision total hip arthroplasty with long or primary stems: a systematic review and meta-analysis

BACKGROUND

Femoral reconstruction with long stems is widely accepted as the standard in revision total hip arthroplasty (rTHA). However, long stems can be technically challenging to insert and can compromise bone stock for future revision. This study aimed to identify whether there was a difference in outcomes with using a long versus primary or short femoral stem in revision.

METHODS

We performed a systematic review and meta-analysis of all articles comparing long and primary stem length in rTHA for Paprosky 1-3B femoral defects. The primary outcome measure was the reoperation rate after rTHA. Secondary outcomes included infection and dislocation rates, periprosthetic fracture, loosening, mortality, and patient-reported outcome measures (PROMs).

RESULTS

The results of 3,102 rTHAs performed in 2,982 patients were reported from 9 eligible studies in the systematic review, of which 6 were included in the meta-analysis. The mean patient age was 67.4 and the mean follow-up lasted 5 years (range, 1-15 years). There was no significant difference in the reoperation rate (odds ratio 0.78; 95% confidence interval, 0.28-2.17, P = 0.63). Similarly, there was no significant difference in dislocation or periprosthetic fracture risk. Harris Hip Score was better with primary stems by a mean difference of 14.4 points (P < 0.05). Pooled 5-year stem-related survival was 91.3% ± 3.5% (SD) for primary stems and 89.9% ± 6.7% (SD) for long stems.

CONCLUSIONS

A primary stem provided non-inferior outcomes compared with long stems in rTHA with Paprosky type 1-3B femoral defects. Primary stems may yield a more straightforward technique and preserve distal bone stock for future revision particularly in younger patients. In older patients with lower functional demands and who would benefit from a decreased risk of complications, a long cemented stem is recommended.

Modular versus monoblock stem in revision total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

Total hip arthroplasty (THA) is estimated to grow in the following decades with a consequent increase of THA revisions (rTHA). This systematic review and meta-analysis aims to compare modular and monoblock stem in rTHA surgery, focusing on clinical and radiological outcomes and complication rates.

METHODS

A literature search was performed using the following search strategy: ((Modular stem) OR (monolithic stem)) AND (hip review) on PubMed, Scopus, and Cochrane. Randomized controlled trials (RCTs) and observational studies (OS) compared clinical and radiological outcomes, and complication rates for monoblock and modular revision femoral stem were included. The risk of bias was assessed through the Methodological Index for Non-Randomized Studies (MINORS) score. The Review Manager (RevMan) software was used for the meta-analysis. The rate of complications was assessed using odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

The authors included 11 OS and one RCT with 3,671 participants (mean age: 68.4 years old). The mean follow-up was 46.9 months. There was no prevalence of subsidence for one type of stem. Mean subsidence was from 0.92 to 10 mm for modular stem and from 1 to 15 mm for monoblock stem. Postoperative Harris Hip Score (HHS) showed better results with modular stems without statistical significance [mean difference (MD) =1.32; 95% CI: -1.62 to 4.27; P=0.38]. No statistically significant difference was found for dislocations (OR =2.48; 95% CI: 0.67 to 9.14; P=0.17), infections (OR =1.07; 95% CI: 0.51 to 2.23; P=0.86), intraoperative fractures (OR =1.62; 95% CI: 0.42 to 6.21; P=0.48), and postoperative fractures (OR =1.60; 95% CI: 0.55 to 4.64; P=0.39).

CONCLUSIONS

Modular and monoblock stems show comparable and satisfactory clinical and radiological outcomes for rTHA. Both stems are valid and effective options for managing femoral bone deficit in hip revision surgery. The main limitation of this study is the small number and low quality of enclosed studies that compared the two stems. Moreover, the modular stem is usually used for more complex cases with lower quality femoral bone stock.

The Fragility Index of Total Hip Arthroplasty Randomized Control Trials: A Systematic Review

INTRODUCTION

Although randomized controlled trials (RCTs) are considered the benchmark study design, a change of outcomes for a few patients can lead to a reversal of study conclusions. As such, examination of the fragility index (FI) of RCTs has become an increasingly popular method to provide further information regarding the relative robustness of RCT results. The purpose of this study was to systematically characterize and assess the predictors of the FI RCTs in total hip arthroplasty literature.

METHODS

PubMed/MEDLINE, Embase, and Cochrane were systematically searched for all total hip arthroplasty RCTs published between January 2015 and December 2020, which had an equal assignment of participants to a two parallel-arm study design, examined a surgical intervention, and reported on at least one statistically significant dichotomous outcome in the abstract. Potential factors associated with the FI were examined using the Spearman correlation and Mann-Whitney U test.

RESULTS

Thirty-four RCTs were selected, with a median number of study participants of 111 (interquartile range [IQR] 72-171] and a median total number of events of 15 (IQR 9.5 to 29). The median FI was 2 (IQR 1 to 6), while six studies had a FI of 0. In 18 cases (52.9%), the number of patients needed to change from no event to event was less than that loss to follow-up. Larger sample size was found to predictive of a higher FI (rs = 0.367, P = 0.033), but the year of publication, journal impact factor, the calculated power analysis size, and loss to follow-up were not associated with FI.

CONCLUSION

The FI serves as a useful addition to other more commonly used approaches of quantitative analyses, such as P values, effect sizes, and confidence intervals, and widespread reporting the FI may provide clinicians with further information about RCT results.

LEVEL OF EVIDENCE

Level I, systematic review of Level I studies.

Effect of mesoporous silica and its combination with hydroxyapatite on the regeneration of rabbit's bone defects: A pilot study

BACKGROUND

Bone volume augmentation is a routine technique used in oral implantology and periodontology. Advances in the surgical techniques and the biomaterials field have allowed a greater accessibility to these treatments. Nevertheless, dehiscence and fenestrations incidence during dental implant procedures are still common in patients with bone loss.

OBJECTIVE

The main objective is to evaluate in a pilot experimental study the biological response to mesoporous silica (MS) hybrid scaffolds and its regenerative capacity in different formulations.

METHODS

Two defects per rabbit tibia were performed (one for control and other for test) and the biomaterials tested in this study have been used to fill the bone defects, prepared in two different formulations (3D hybrid scaffolds or powdered material, in 100% pure MS form, or 50% MS with 50% hydroxyapatite (HA). Euthanasia was performed 4 months after surgery for bone histopathological study and radiographic images were acquired by computerized microtomography.

RESULTS

Results showed that radiographically and histopathologically pure MS formulations lead to a lower biological response, e.g when formulated with HA, the osteogenic response in terms of osteoconduction was greater.

CONCLUSIONS

We observed tolerance and lack of toxicity of the MS and HA, without registering any type of local or systemic allergic reaction.

A Novel Fast Mobile-Window Small Incision Technique for Hip Arthroplasty in the Elderly and Comparison with Conventional Incision

Background

We deeloped a novel technique – fast mobile-window small incision (FMWSI) – a modification of minimally invasive surgery for total hip arthroplasty, which we believe is particularly suited to elderly patients with hip fractures. The present article aimed to introduce this technique and compare the clinical effects between the FMWSI technique and conventional incision (CI) for hip arthroplasty in elderly patients.

Material/Methods

This study included 240 consecutive patients who underwent hip arthroplasty. Half received total hip arthroplasty and half received hemi hip arthroplasty. The 120 patients in each group were further divided into FMWSI and CI groups. The following parameters were compared between the FMWSI and CI groups: length of incision, operation time, bleeding volume, drainage volume, postoperative ambulation time, and Harris score.

Results

Compared with the CI group, the FMWSI group had a significantly shorter incision length, operation time, and postoperative ambulation time, as well as lower bleeding and drainage volumes, irrespective of whether the treatment was total or hemi hip arthroplasty (P<0.05). However, no significant difference was found in the Harris score between the FMWSI and CI groups (P>0.05).

Conclusions

The novel FMWSI technique introduced in this study is a useful method for hip arthroplasty, especially for elderly patients with poor constitutions or tolerance to surgery.

Fabrication and Characterization of Carbon Fiber-Reinforced Nano-Hydroxyapatite/Polyamide46 Biocomposite for Bone Substitute

Background

Ideal bone repair material should be of good biocompatibility and high bioactivity. Besides, their mechanical properties should be equivalent to those of natural bone. The objective of this study was to fabricate a novel biocomposite suitable for load-bearing bone defect repair.

Material/Methods

A novel biocomposite composed of carbon fiber, hydroxyapatite and polyamide46 (CF/HA/PA46) was fabricated, and its mechanical performances and preliminary cell responses were evaluated to explore its feasibility for load-bearing bone defect repair.

Results

The resultant CF/HA/PA46 biocomposite showed a bending strength of 159–223 MPa, a tensile strength of 127–199 MPa and a tensile modulus of 7.7–10.8 GPa, when the CF content was 5–20% (mass fraction) in biocomposite. The MG63 cells, showing an osteogenic phenotype, were well adhered and spread on the surface of the CF/HA/PA46 biocomposite. Moreover, the cells vitality and differentiation on the CF/HA/PA46 biocomposite surface were obviously increased during the culture time and there was no significant difference between the CF/HA/PA46 biocomposite and HA/PA (as control) at all the experimental time (P>0.05).

Conclusions

The addition of CF into HA/PA46 composite manifest improved the mechanical performances and showed favorable effects on biocompatibility of MG63 cells. The obtained biocomposite has high potential for bone repair in load-bearing sites.

Comparison of Biocompatibility of Cemented vs. Cementless Hip Joint Endoprostheses Based on Postoperative Evaluation of Proinflammatory Cytokine Levels

BACKGROUND The yearly increase in the number of procedures involving implantation of hip joint endoprostheses forces prosthetics manufacturers to search for biologically neutral implants. The goal of this study was to assess the concentration of Interleukin-6 (IL-6) and its correlation with C-reactive protein (CRP), depending on the type of hip joint endoprosthesis (cemented or cementless endoprosthesis) in order to determine implant biotolerance during the early postoperative period. MATERIAL AND METHODS The sample comprised 200 patients [mean age=64 (31-81) years] with coxarthrosis. All patients underwent hip joint arthroplasty using a cemented or cementless endoprosthesis. Blood samples were collected 3 times: before the procedure, on the first day after the procedure, and after 6 weeks. IL-6 and CRP levels were assayed using immunoenzymatic methods. The results were subjected to statistical analysis using the Shapiro-Wilk test. RESULTS On the 1st day after the procedure, CRP and IL-6 concentration increased rapidly after implantation of both cemented and cementless endoprostheses. At 6 weeks postoperatively, the CRP value remained at a similar level in patients after cemented arthroplasty and was almost 2-fold lower in patients who underwent cementless arthroplasty. The IL-6 value returned to the baseline level in patients after cementless arthroplasty and showed an ongoing increasing tendency in patients after cemented arthroplasty. CONCLUSIONS 1. The measurement of C-reactive protein and Interleukin-6 is a high-sensitivity test, assessing implant biotolerance. 2. The implantation of a cemented endoprosthesis induces a higher increase in the level of proinflammatory cytokines as compared with a cementless endoprosthesis. 3. For a complete assessment of both early and later body responses to implantation and the related surgical procedure, further studies using available approaches and tools are recommended.