Cementless bipolar hemiarthroplasty using a micro-arc oxidation coated stem in patients with displaced femoral neck fractures

Recent development and applications of electrodeposition biocoatings on medical titanium for bone repair

Bioactive coatings play a crucial role in enhancing the osseointegration of titanium implants for bone repair. Electrodeposition offers a versatile and efficient technique to deposit uniform coatings onto titanium surfaces, endowing implants with antibacterial properties, controlled drug release, enhanced osteoblast adhesion, and even smart responsiveness. This review summarizes the recent advancements in bioactive coatings for titanium implants used in bone repair, focusing on various electrodeposition strategies based on material-structure synergy. Firstly, it outlines different titanium implant materials and bioactive coating materials suitable for bone repair. Then, it introduces various electrodeposition methods, including electrophoretic deposition, anodization, micro-arc oxidation, electrochemical etching, electrochemical polymerization, and electrochemical deposition, discussing their applications in antibacterial, osteogenic, drug delivery, and smart responsiveness. Finally, it discusses the challenges encountered in the electrodeposition of coatings for titanium implants in bone repair and potential solutions.

Differences in periprosthetic bone mineral density tendencies with Types 1 and 3C stems in bipolar hemiarthroplasty following hip fracture

The purpose of this study was to compare the periprosthetic bone mineral density (BMD) changes in the patients who underwent bipolar hemiarthroplasty (BPHA) for geriatric femoral neck fracture between two major different types of cementless femoral stems. A total of 93 patients (96 hips) who underwent BPHA for femoral neck fracture were categorized into two groups: Type 1 (42 patients, 44 hips), and Type 3C stem (51 patients, 52 hips). We investigated the annual follow-up trends of periprosthetic BMD at each Gruen zone during minimum postoperative 5-years; moreover, we compared the trends of periprosthetic BMD between both groups. The mean follow-up period was 7.1 years. In both groups, the overall BMD at the last follow-up had decreased compared with the baseline. In those with the Type 1 stem, BMD in the lateral femoral meta-diaphysis significantly decreased at 1-year follow-up after surgery. In those with Type 3C stem, BMD in the lateral femoral metaphysis postoperatively decreased after 3-years, whereas the BMD in the mediolateral femoral diaphysis drastically decreased postoperative 1-year period and plateaued thereafter. Different tendencies according to stem design were observed obviously in the postoperative BMD change of the proximal femur in patients who underwent BPHA for geriatric femoral neck fracture.

Minimum 10-year follow-up of micro-arc oxidation coating on a cementless grit-blasted tapered-wedge stem of total hip arthroplasty: a multicentre study

BACKGROUND

Recently, a femoral stem treated with grit-blasting and micro-arc oxidation (MAO) coating has commercialised but medium-term follow-up studies are lacking. The aim of this study was to report the outcome of a grit-blasted and MAO-coated femoral component designed as a straight, double-wedged, tapered stem with a rectangular cross-section with minimum 10 years follow-up.

METHODS

Between March 2006 and December 2008, 309 primary total hip arthroplasties using a grit-blasted and MAO-coated femoral component were performed by 3 experienced hip surgeons in 3 hospitals. At minimum 10 years after index THA, 299 hips were living, 10 hips were deceased, and 65 hips were lost to follow-up or had a follow-up period <10 years. Finally, 234 hips were enrolled in this study.

RESULTS

Mean duration of clinical follow-up was 129.6 months. The mean Harris Hip Score was improved from 46.9 to 88.4 at the final follow-up. 4 hips were revised for 2 aseptic femoral loosening, 1 aseptic acetabular cup loosening and 1 late infection. 3 hips were revised for a periprosthetic femoral fracture requiring a femoral component revision. The average time to revision was 51.6 (range 0-148) months. Kaplan-Meier survivorship analysis with an end point of revision for any reason demonstrated a survival rate of 97.4% at 10 years. Survival was 98.7% with revision for aseptic loosening as the endpoint.

CONCLUSIONS

The outcomes of a cementless grit-blasted and MAO-coated tapered-wedge stem of THA were excellent to satisfactory after a follow-up of at least 10 years.

Perioperative Mortality After Cemented or Uncemented Hemiarthroplasty for Displaced Femoral Neck Fractures-A Systematic Review and Meta-analysis

BACKGROUND

Debate surrounds the use of cemented or uncemented prostheses for the treatment of displaced femoral neck fractures (FNF). Many guidelines recommend the use of the cemented hemiarthroplasty (CHA). Proponents of CHA point out the increased re-operation rate while proponents of uncemented hemiarthroplasty (HA) highlight the increased mortality rate in the perioperative period. The aim of this study was to systematically review the literature to evaluate perioperative mortality after HA for displaced FNFs.

METHODS

A systematic review and meta-analysis was performed of MEDLINE, Cochrane Library, and Embase databases evaluating perioperative mortality after HA for displaced FNFs. Randomized control trials and observational studies were included comparing current-generation stem designs. A meta-analysis was performed on studies that directly compared the different modes of fixation.

RESULTS

Twenty-two studies were included (seven randomized control trials and 15 observational studies), with a total of 183,167 HAs for treatment of a displaced FNF. Fourteen studies were included in the meta-analysis. There was a higher cumulative odds of death within the first 48 hours in those with CHA compared with uncemented HA (OR: 1.64; 95% CI: 1.35, 2.00; P ≤ .01). No difference was found in mortality at 7 days, 30 days, and one year.

CONCLUSION

CHA is associated with an increased mortality rate within the first two days of surgery with no difference at 7 days, 30 days, and one year. Surgeons should consider tailoring their stem choice based on the physiological status of the patient when planning HA for FNFs. Techniques to reduce the risk of bone cement implantation syndrome should be used.

On-Table and Short-Term Mortality: A Single-Institution Experience With Cementing All Hip Arthroplasties for Neck of Femur Fractures

BACKGROUND

To review on-table, day 0, day 1, day 7, and day 30 mortality after hemiarthroplasty or total hip arthroplasty (THA) using cemented femoral stems for femoral neck fractures in order to evaluate risk factors for perioperative and short-term mortality.

METHODS

The medical records of 751 consecutive cases with neck of femur fractures who underwent hemiarthroplasty (n = 602) or THA (n = 149) with cemented stems between January 2011 and December 2016 were retrospectively reviewed from a prospectively gathered database. The primary outcome measures were on-table, day 0, day 1, day 7, and day 30 mortality. Univariate and multivariate analyses were performed in order to identify various contributing patient and surgical variables.

RESULTS

There were 2 on-table deaths (0.27%): one patient had a cardiorespiratory arrest at the time of inserting the femoral stem and the other had a cardiorespiratory arrest at the end of wound closure some 20 minutes after cementing. There were 3 further day 0 deaths meaning the day 0 mortality rate was 0.67% (5/751). All 5 patients were older than 80 years and had an American Society of Anesthesiologists grade 3 or more. The 1-day, 7-day, and 30-day mortality rates were 0.93% (7 patients), 2.7% (20 patients), and 6.8% (51 patients), respectively. There is significantly higher 30-day mortality risk associated with increasing American Society of Anesthesiologists grade (P < .001) when adjusted for age, gender, and type of surgery (hemiarthroplasty compared with THA).

CONCLUSION

In our neck of femur fracture patients who were operated with cemented stems, 7-day and 30-day mortality rates were 2.7% and 6.8%, respectively. Cemented stems should be used with caution in elderly hip fracture patients with multiple comorbidities who are at high risk of perioperative mortality.

Bipolar hemiarthroplasty using microarc oxidation-coated cementless stem in patients with unstable intertrochanteric fracture

PURPOSE

Treatment for an unstable intertrochanteric fracture in elderly patients is challenging. Bipolar hemiarthroplasty (HA) using microarc oxidation (MAO) coating has been a treatment option alternative to internal fixation. However, the outcome of bipolar HA using MAO-coated stem in these patients is unknown.

METHODS

From July 2007 to April 2016, 234 (older than 65 years) patients (234 hips) who were diagnosed as having unstable intertrochanteric fractures were treated with bipolar HA using a fully MAO-coated standard-length rectangular cementless stem. During the arthroplasty, the greater trochanteric and the medial fracture fragments were attached to the stem and fixed with two to three 16-gauge wires. Forty-eight patients (48 hips) died within postoperative 2 years. The remaining 186 patients (186 hips) were followed up for a mean of 4.3 (range 2-10) years.

RESULTS

With the exception of 4 patients who died during hospitalization, 176 of 230 ( 76.5%) patients could ambulate independently with or without an assistive device at the time of hospital discharge. Venous thromboembolism occurred in seven patients (3.0%). One hip dislocated due to a fall 1 month after the arthroplasty. Periprosthetic femoral fracture occurred in four patients and periprosthetic acetabular fracture in one patient. One patient had periprosthetic of acute pyelonephritis. There was no focal osteolysis around the femoral stem.

CONCLUSION

The result of cementless HA using MAO-coated stem enabled early ambulation in most (76.5%) of elderly patients with unstable intertrochanteric fractures and the results were encouraging.

Favorable Functional Recovery and Stem Stability after Hip Arthroplasty with a Short Metaphyseal Stem in Elderly Patients with Osteoporotic Femoral Neck Fractures

Purpose

Short stems have recently become widely used; however, concerns about the initial secure fixation of a short stem in osteoporotic bone remain. The aim of this study was to evaluate the short-term clinical and radiological results of using a short cementless metaphyseal stabilizing tapered stem for senile osteoporotic femoral neck fractures.

Materials and Methods

Thirty-eight arthroplasties (31 bipolar hemiarthroplasties and 7 total hip arthroplasties) were performed for osteoporotic femoral neck fractures in patients older than 65 years (10 males and 28 females). The mean age was 76.1 years and the mean follow-up was 2.9 years. We retrospectively evaluated clinical results, focusing on walking performance, thigh pain, and radiologic results, with special regard to signs of stem stability and osteointegration.

Results

Mean Harris hip score was 84.3 points and 68.4% of patients regained their preoperative walking performance. No patients complained about thigh pain. No osteolysis or loosening was observed during the follow-up, and all but 1 stem showed signs of stable bone ingrowth.

Conclusion

Short, metaphyseal stabilizing tapered stems could be a reliable treatment option for osteoporotic femoral neck fractures.

Frequency and associated factor of atypical periprosthetic femoral fracture after hip arthroplasty

BACKGROUND

Atypical femoral fracture (AFF) is a serious complication after the use of bisphosphonates, and periprosthetic femoral fracture (PFF) appeared as a common complication after hip arthroplasty, especially in senile patients. Although American Society for Bone and Mineral Research has excluded PFFs from the definition of AFFs, several case reports found PFF patients undergoing bisphosphonate treatment, have fractures resembling AFF and the authors suggested that AFF can also occur in operated femurs after hip arthroplasty. To date, the frequency and risk factors of atypical PFF are unknown. The purpose of our study was (1) to evaluate the proportion of atypical PFF among Vancouver type B PFFs, and (2) to determine the association between occurrence of atypical PFF and use of bisphosphonate.

METHODS

We reviewed medical records and radiographs of 67 Vancouver type B PFFs (67 patients) due to low-energy trauma and classified them into atypical PFF group and ordinary PFF group. We calculated the proportion of atypical PFFs among PFFs and identified risk factors for atypical PFF.

RESULTS

Among the 67 PFFs, 7 fractures (10.4%) were classified as atypical PFF. Longer duration of bisphosphonate use was an independent risk factor of atypical PFF. (Odds ratio 2.600, 95% CI 1.184-5.709, p = 0.017).

CONCLUSION

In accordance with wide use of bisphosphonate, atypical PFFs after hip arthroplasty are not rare anymore. Physicians should suspect the atypical PFF, when they meet low-energy fracture in bisphosphonate users, and radiographs show features of AFF.

What Is the Frequency of Early Dissociation of Bipolar Cups and What Factors Are Associated With Dissociation?

BACKGROUND

Dissociation between a prosthetic cup and femoral head is a rare complication of bipolar hemiarthroplasty that usually occurs during closed reduction of a dislocated bipolar cup. The dissociation usually results in reoperation because closed reduction is challenging. To our knowledge, no study has reported on the frequency of bipolar cup-femoral head dissociation, and risk factors for dissociation are unknown.

QUESTIONS/PURPOSES

The purposes of this study were (1) to evaluate the frequency of dissociation of prosthetic femoral heads from bipolar cups during manual reduction of a dislocated bipolar hemiarthroplasty; and (2) to explore in a preliminary fashion any prosthesis or patient factors that may be associated with dissociation.

METHODS

From May 2003 to August 2016, 60 bipolar hemiarthroplasties were treated at three institutions as a result of early (within 3 years) dislocation after arthroplasty; of these, 55 could be identified and categorized in terms of the type of locking mechanism used, and these were the patients evaluated in this retrospective study. Because the index hemiarthroplasties were not performed exclusively at the three participating centers, we cannot comment on the indications for prosthesis selection in these patients (such as why some patients may have received components with single rather than double locking mechanisms). Manual reduction was attempted in all patients. Although 34 dislocations were manually reduced, 21 hips underwent surgical intervention because they could not be closed reduced (14 hips) or because of bipolar cup-femoral head dissociation (seven hips). We compared patients' demographics and prosthetic factors between the dissociation group (n = 7) and the nondissociation group (n = 48).

RESULTS

Bipolar cup-femoral head dissociation occurred in seven of 55 patients with dislocations (13%). Among the seven dissociated cups, six had a single polyethylene locking ring, whereas 20 of 48 nondissociation cups (42%) had the single locking ring (p = 0.044). We found no other patient or prosthesis factors associated with dissociation.

CONCLUSIONS

Bipolar cups with a single locking mechanism (rather than a double locking mechanism) may be associated with an increased risk of bipolar cup-femoral head dissociation. However, because we could not evaluate prosthesis indications in this study, and because our sample size was too small to control for potential confounding variables, future studies are needed to confirm this finding. All the same, because good alternatives are available, we do not recommend the use of this type of locking mechanism in bipolar hemiarthroplasty.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Additively Manufactured Macroporous Titanium with Silver-Releasing Micro-/Nanoporous Surface for Multipurpose Infection Control and Bone Repair - A Proof of Concept

Restoring large-scale bone defects, where osteogenesis is slow while infections lurk, with biomaterials represents a formidable challenge in orthopedic clinics. Here, we propose a scaffold-based multipurpose anti-infection and bone repairing strategy to meet such restorative needs. To do this, personalized multifunctional titanium meshes were produced through an advanced additive manufacturing process and dual "TiO₂-poly(dopamine)/Ag (nano)" post modifications, yielding macroporous constructs with micro-/nanoporous walls and nanosilver bullets immobilized/embedded therein. Ultrahigh loading capacity and durable release of Ag⁺ were accomplished. The scaffolds were active against planktonic/adherent bacteria (Gram-negative and positive) for up to 12 weeks. Additionally, they not only defended themselves from biofilm colonization but also helped destroy existing biofilms, especially in combination with antibiotics. Further, the osteoblasts/bacteria coculture study displayed that the engineered surfaces aided MG-63 cells to combat bacterial invasion. Meanwhile, the scaffolds elicited generally acceptable biocompatibility (cell adhesion, proliferation, and viability) and hastened osteoblast differentiation and maturation (alkaline phosphatase production, matrix secretion, and calcification), by synergy of micro-/nanoscale topological cues and bioactive catecholamine chemistry. Although done ex vivo, these studies reveal that our three-in-one strategy (infection prophylaxis, infection fighting, and bone repair) has great potential to simultaneously prevent/combat infections and bridge defected bone. This work provides new thoughts to the use of enabling technologies to design biomaterials that resolve unmet clinical needs.

Bioinspired anchoring AgNPs onto micro-nanoporous TiO2 orthopedic coatings: Trap-killing of bacteria, surface-regulated osteoblast functions and host responses

The therapeutic applications of silver nanoparticles (AgNPs) against biomedical device-associated infections (BAI), by local delivery, are encountered with risks of detachment, instability and nanotoxicity in physiological milieus. To firmly anchor AgNPs onto modified biomaterial surfaces through tight physicochemical interactions would potentially relieve these concerns. Herein, we present a strategy for hierarchical TiO2/Ag coating, in an attempt to endow medical titanium (Ti) with anticorrosion and antibacterial properties whilst maintaining normal biological functions. In brief, by harnessing the adhesion and reactivity of bioinspired polydopamine, silver nanoparticles were easily immobilized onto peripheral surface and incorporated into interior cavity of a micro/nanoporous TiO2 ceramic coating in situ grown from template Ti. The resulting coating protected the substrate well from corrosion and gave a sustained release of Ag(+) up to 28 d. An interesting germicidal effect, termed "trap-killing", was observed against Staphylococcus aureus strain. The multiple osteoblast responses, i.e. adherence, spreading, proliferation, and differentiation, were retained normal or promoted, via a putative surface-initiated self-regulation mechanism. After subcutaneous implantation for a month, the coated specimens elicited minimal, comparable inflammatory responses relative to the control. Moreover, this simple and safe functionalization strategy manifested a good degree of flexibility towards three-dimensional sophisticated objects. Expectedly, it can become a prospective bench to bedside solution to current challenges facing orthopedics.

The Early Result of Cementless Arthroplasty for Femur Neck Fracture in Elderly Patients with Severe Osteoporosis

Purpose

The purposes of the current study were to assess the early results of cementless hip arthroplasty (HA) for femoral neck fractures in elderly patients with severe osteoporosis and to compare the clinical outcomes between those who underwent total HA (THA) or bipolar hemiarthroplasty (BHA).

Materials and Methods

From April 2011 to May 2012, we performed 87 cementless HAs for displaced femoral neck fractures in elderly patients (≥65 years) with severe osteoporosis. Among them, we studied 70 hips that were able to be followed-up for >24 months. Of these, 34 underwent THA and 36 underwent BHA. Clinical results were evaluated using the Harris hip score (HHS), Koval classification, and radiographs.

Results

Only one instance of femoral stem loosening was observed. Additionally, no dislocations were observed and no revision surgeries were required. The mean changes in the functional items of the HHS scores were 2.8 and 5.2 for those who underwent THA and BHA, respectively (P<0.05). According to the Koval classification used for the ambulatory status analysis, the mean perioperative change in the grade was 0.8 (0-4), with no significant differences noted between the THA and BHA groups.

Conclusion

The early results of cementless HA for femur neck fractures in elderly patients with osteoporosis were satisfactory, and THA was found to have a functional advantage over BHA.