What's new in total hip arthroplasty

Hip joint-preserving strategies for treating osteonecrosis of the femoral head: From nonoperative to operative procedures

Osteonecrosis of the femoral head (ONFH) has an exceedingly high prevalence and disability rate, causing a tremendous socioeconomic burden. The prevalence of ONFH is increasing, while the population of the patients with ONFH is becoming younger. Once the femoral head collapses, treatment becomes difficult and often requires a hip joint replacement, which is not favorable for young patients. Therefore, hip joint-preserving treatments at an early stage of ONFH are particularly important. This study provides a comprehensive review on hip-preserving strategies for treating ONFH, including nonoperative treatments (e.g., protective weight bearing, hyperbaric oxygen, pulsed electromagnetic, extracorporeal shockwave, bisphosphonate, anticoagulants, hypolipidemics, vasodilators, and traditional Chinese medicine) and operative treatments (e.g., core decompression, osteotomy, bone grafting, mesenchymal stem cell transplantation, tantalum rods, and tissue engineering). Nonoperative treatments aim to slow down the progression of the disease and delay the need for joint replacement; however, they usually cannot effectively prevent the progression of the disease, except in cases of small necrosis areas (<10 %). Additionally, nonoperative treatments have unclear mechanisms that require further investigation. In contrast, operative treatments may stop the negative outcomes of necrosis and therefore appear to be more promising. Currently, an emerging area in operative treatments is regenerative medicine, which could promote the generation of bone tissues and blood vessels and restore hip joint function to pre-necrotic levels as much as possible. This review seeks to not only provide an important reference for clinicians when choosing appropriate strategies for treating ONFH but also offer certain guidance for future basic research in developing ONFH treatments.

The translational potential of this article

The incidence of ONFH is increasing, and patients are becoming younger on average. Therefore, the development of hip joint-preserving strategies to treat ONFH at earlier stages is urgently needed, particularly for young patients. However, a comprehensive review is lacking regarding the currently-available hip joint-preserving strategies and their effectiveness. This study is motivated to fill this gap and serve as an important reference for clinicians in choosing appropriate strategies to treat ONFH.

TOTAL HIP ARTHROPLASTY IN THE PUBLIC HEALTH SYSTEM OF SÃO PAULO: COMPARING TYPES OF FIXATION

ABSTRACT Brazil lacks registries on the prevalence of primary total hip arthroplasty (THA) fixation methods. Objective: (i) to describe the demographic profile of patients who underwent THA in the public health system of the municipality of São Paulo during the last 12 years and (ii) to compare fixation methods regarding costs, hospital stay length, and death rates. Methods: This is an ecological study conducted with data available on TabNet, a platform belonging to DATASUS. Public data (from the government health system) on THA procedures performed in São Paulo from 2008 to 2019 were extracted. Gender, age, city region, THA fixation method, number of surgeries, costs, hospital stay length, and death rates were analyzed. Results: We analyzed 7,673 THA, of which 6220 (81%) were performed via cementless/hybrid fixation and 1453 (19%), via the cemented technique. Cementless/hybrid fixation had a higher cost (US$ 495.27) than the cemented one (p < 0.001). Nevertheless, hospital stay length was 0.87 days longer for cemented fixation than the cementless/hybrid one. We found no significant difference in death rates between THA fixation methods. Conclusion: THA cementless/hybrid fixation is prevalent in the municipality of São Paulo, which had higher total costs and shorter hospitalizations than cemented fixation. We found no difference between THA fixation methods and death rates. Level of Evidence IV, Case Series.

Clinical usefulness of single photon emission tomography/computed tomography with stress analysis in early diagnoses of stem instability of noncemented hip arthroplasty

OBJECTIVE

Hip pain arising from implant instability is generally caused by repetitive stress injury, which subsequently leads to induction or exacerbation of abnormal metabolism of bone around the implant. single photon emission tomography/computed tomography (SPECT-CT) has advantages in localizing areas of increased tracer uptake that reflects such abnormal bone metabolism. Therefore, we investigated whether the application of SPECT/CT with stress analysis can be an effective practice in evaluating the instability of stem in noncemented hip arthroplasty or not.

METHOD

In total 16 patients were collected for unexplained painful hip arthroplasties. When physical examination and blood tests were unremarkable, radiographs were inconclusive and bone scan indicated increased scintigraphic uptake at the proximal part and at the tip of the stem; SPECT/CT was performed. Stem stability was assessed by measuring whether there was consistency between the increased scintigraphic uptake and the direction of the stress around the implant along with the location of the prosthesis.

RESULT

Among the 16 symptomatic hips, 9 hips showed the stability of the stem, 3 hips showed the stem instability and 4 hips showed the acetabular loosening with the stem stability. With the application of SPECT/CT with stress analysis, 15 out of 16 (93.7%) cases were found to have the change in the diagnoses, and managements were implemented in 11 out of 16 (68.7%) cases. When comparing before and after SPECT/CT, there was no significant association in clinical diagnosis and management (Pearson chi- square test = 4.61 and 1.33, P = 0.33 and 0.25).

CONCLUSION

SPECT/CT combined with stress analysis can be a useful tool in early diagnosis of stem instability and can assist surgeons in subsequent management and decision implementation when other radiographic imagings are inconclusive.

The effect of posterior capsule repair in total hip arthroplasty: a systematic review and meta-analysis

Background

Prior studies have compared the posterior capsule repair group in primary total hip arthroplasty by posterior approach with the control group without posterior capsule repair suggesting that the posterior capsule repair group had better clinical outcomes. However, it is still a controversy which treatment is more helpful for hip diseases. The purpose of our article is to obtain the postoperative outcomes between the 2 procedures.

Methods

We performed a systematic search by browsing the MEDLINE, EMBASE, Cochrane Library. There is no restriction on the date of publication. Before we submit our manuscript, we have re-searched the literatures again, including the articles which directly compared the postoperative outcomes of the 2 procedures.

Results

A total of 8 comparative studies were included in our meta-analysis. The posterior capsule repair group showed less dislocation rate, higher HHS, and even less postoperative bleeding volume. Meanwhile, there is no significant difference in ROM between 2 groups.

Conclusion

In conclusion, according to current evidences, repairing posterior capsule during primary THA may have better functional outcomes, less dislocation incidence, and less loss of blood.

Ceramic on Ceramic or Ceramic-on-polyethylene for Total Hip Arthroplasty: A Systemic Review and Meta-analysis of Prospective Randomized Studies

BACKGROUND

Wear debris of polyethylene has become a restraining factor of the durability for total hip arthroplasty (THA). Ceramic on ceramic (COC) has better wear resistance while the squeaking sound and prosthesis fracture are of concern. It is still a controversy that bearing couples are better for THA.

METHODS

We performed a systematic review of all English articles identified from PubMed (1966-), Embase (1980-) and the Cochrane Library. Clinical outcomes, complications, revision rates, and radiographic outcomes of COC-THA and ceramic on polyethylene (COP)-THA were compared and evaluated.

RESULTS

Eight prospective randomized trials enrolling a total of 1508 patients and 1702 THA surgeries were identified. Our results demonstrated the prosthesis fracture and the squeaking sound is significantly higher in COC group and higher wear rate of the COP. Hip function, loosening rate, dislocation rate, revision rate, and the osteolysis rate were comparable between two groups. According to Grading of Recommendations Assessment, Development and Evaluation system assessment, the strength of evidence was high for prosthesis fracture, dislocation, osteolysis, and moderate for radiolucent line or loosening, hip noise, and revision.

CONCLUSIONS

Up to now, there is insufficient evidence to identify any clinical advantage of COC compared with COP. Longer follow-up of larger randomized trial is needed to clarify the outcomes.

Impact of Total Hip Resurfacing Arthroplasty on Health-Related Quality of Life Measures: A Systematic Review and Meta-Analysis

The aim of this study was to investigate the effect of total hip resurfacing arthroplasty (RA) on general health-related quality of life (HRQOL) and disease/hip-specific measures. Original studies published after 2000, enrolling at least ten skeletally mature patients with a minimum follow-up of 6 months were considered. The standardized mean difference (SMD) was obtained with a random effects model. The cumulative patient population encompassed 1898 patients (2123 RA). Mean follow-up duration was 4 years. The physical component score (P<0.001) and mental component score (P=0.05) of SF-12, and the EuroQol-5D (P<0.0001) improved significantly. WOMAC global score and the subscales (P<0.00001) were also improved. Harris Hip Score (P<0.00001), Oxford Hip Score (P<0.001) and UCLA (P<0.00001) were markedly improved and patient satisfaction was favorable.

A multidisciplinary enhanced recovery programme allows discharge within two days of total hip replacement; three- to five-year results of 100 patients

We present three- to five- year results of 100 sequential patients undergoing total hip replacement (THR) through a multidisciplinary rapid recovery programme, with mean length of stay (LOS) 1.99 nights. Patients attend pre-admission 'bone school', with talks and assessments by the senior sister, physiotherapist and occupational therapist. All receive an uncemented Corail-Pinnacle THR via piriformis-sparing mini-posterior approach. 'Low dose' spinal plus light general anaesthesia provides sensory block whilst retaining motor function; painfree mobilisation is predictably achieved within four hours. Following radiograph and haemoglobin check next morning, patients are discharged on meeting specific nursing/physiotherapy criteria. Those within 20 miles receive outreach follow-up. Follow-up assessment is undertaken using SF36, Visual Analogue, Merle d'Aubigné-Postel and Oxford Hip Scores. Mean age was 65 years (25-91), mean BMI 28.7 (19-43). ASA ranged 1-3 (mode 2), Charlson comorbidity index from 0-9 (mode 3). Major complications were: one dislocation with deep infection; one myocardial infarction; one trochanteric bursitis requiring exploration; one ceramic fracture; and three metal debris reactions. Several more minor complications occurred. LOS was longer in older patients (p = 0.03) and those with higher Charlson index (p = 0.02).Eighty-two patients remain under follow-up, (mean 37.8 months, range 36-61). Six have died; five underwent revision; seven have moved away or been lost. Ninety-seven percent remain quite or very satisfied. Our LOS is amongst the shortest in the United Kingdom, with encouraging outcomes. The SSP succeeds by involving all team-members, and managing patient expectation. At a time of limited healthcare resources we propose that our SSP could readily be reproduced elsewhere with similar benefits.

Diagnosis and Management of Periprosthetic Shoulder Infections

➤ The unique bacterial flora of the shoulder present diagnostic and treatment challenges that are distinct from those seen with failed hip and knee arthroplasties.➤ The presentation, diagnosis, and management of suppurative periprosthetic joint infections of the shoulder are similar to those of the hip and the knee.➤ Failed arthroplasties with positive cultures (FAPCs) are poorly performing shoulder reconstructions associated with low-virulence microorganisms that do not evoke a suppurative inflammatory response. Propionibacterium acnes is the predominant bacterium isolated from these cases.➤ With improved surgeon awareness and the addition of longer tissue-culture incubation times, detection of FAPCs has become more common. However, management is hampered by the lack of reliable, timely tests that can determine the presence of less virulent organisms in the preoperative or intraoperative settings.➤ The implications of positive culture results in FAPCs are unclear. Key test characteristics such as the false-positive rate and the prevalence of positive cultures in well-performing shoulders are unknown as there is no useful confirmatory test to validate the culture data and no reliable way to detect the presence of less virulent microorganisms without reoperation.➤ Soft-tissue and osseous deficits are frequently encountered when revising previously infected shoulders. The rate of complications in these scenarios is high, and the outcomes are the least favorable compared with revisions for any other indication.➤ The development of a consensus definition of a periprosthetic shoulder infection is critical to future investigations of these devastating complications.

Resurfacing hip replacement and cemented total hip replacement have equivalent outcome at one year in a disease matched population: a case-control study of patient reported outcome measures

Resurfacing hip replacement has demonstrated good survival and outcomes for cohorts of younger male patients, but few controlled studies exist. In this study we compared patient reported outcome measures and satisfaction scores at one year following resurfacing hip replacement in 69 male patients with two control groups of equal numbers undergoing cemented total hip replacement: aged-matched patients and disease matched patients. At one year we found no difference in improvement in patient reported outcome measures between patients undergoing resurfacing hip replacement and disease matched patients, whereas patients undergoing resurfacing hip replacement had a statistically significant improvement in Oxford Hip Score compared to the age-matched controls (p<0.047) although this was below the minimally clinically detectable difference. Resurfacing hip replacement and total 
hip replacement both confer increase in patient reported outcome scores and high patient satisfaction at one year. The results of this study will allow better counselling of patients and help inform 
treatment decisions.

How to measure wear following total hip arthroplasty

Total hip arthroplasty has yielded excellent results in decreasing pain and enhancing function in patients with hip degenerative disease. However, the problems associated with prosthetic failure and the consequent need for revision surgery still represent a major clinical issue. The most common reasons for revision surgery include implant loosening, periprosthetic osteolysis, infection, malalignment, stiffness, implant failure or fracture, and wear. The need for eliminating or reducing wear plays a crucial role in refining prosthesis composition and design. In this regard, it is important to develop new techniques for more accurate and reproducible measurement of wear. This should allow earlier detection of increased wear and thus permit earlier identification of patients who are at risk, and also help to identify faulty implant designs.
This work is aimed at discussing the most common in vivo and in vitro methods used for evaluating the wear of hip prosthesis components.

Dimensional analysis of total hip arthroplasty polyethylenes

Objective

This paper performs a dimensional analysis of different total hip arthroplasty polyethylenes, cemented and non-cemented, Brazilian made and imported.

Methods

It was considered acetabular components with 50 mm for the 28 mm femoral heads. Dimensional analysis was performed on a 3D coordinate Carl-Zeiss robotic device. Polyethylene thickness and its external measurements (maximum diameter and diameter for the femoral head) were measured.

Results

The minimum thickness of the polyethylene was guaranteed on all tested components. The thickness of cemented acetabular varied from 19.185 mm to 25.358 mm, while the thickness of the non-cemented acetabular varied from 12.451 mm to 19.232 mm. The thickness was 27.96% lower in non-cemented acetabular components. With respect to the polyethylene acetabular cavity that receives the femoral head, all internal diameters exhibit at least 28 mm. In relation to the maximum outer diameter of the polyethylene, only one cemented acetabular component reached 50 mm in diameter.

Conclusions

There are large differences in measurements between brands and models analyzed. Cementless acetabular components have the smaller thickness. The diameters of non-cemented acetabular were also lower than those cemented at the expense of their need to insert into the metal-back.

Current concepts of hip arthroplasty for radiologists: part 2, revisions and complications

OBJECTIVE

This article reviews the imaging features of revisions and complications of hip replacement arthroplasty and relates these features to the current understanding about how and why these failures occur.

CONCLUSION

Short-term failures of hip replacements are most commonly the result of instability and dislocation. Complications ranging from osteolysis caused by granulomatous reaction to particulate wear debris lead to many long-term failures. Attempts to reduce wear debris through changes in design and materials have reduced the rate of some complications but have resulted in new ones. Infection remains a devastating complication that is difficult to resolve.

NEW BEARING SURFACES IN TOTAL HIP REPLACEMENT

Total hip arthroplasty is being increasingly indicated for younger and more active patients, in addition to a naturally growing demand for the procedure because of increasing life expectancy among patients. The high costs of this surgery and the controversies regarding implant performance have made this topic the subject of constant research, seeking new materials with better resistance to wear and better biocompatibility. The present article provides a review of new surfaces in total hip arthroplasty.

Metal-on-metal or metal-on-polyethylene for total hip arthroplasty: a meta-analysis of prospective randomized studies

BACKGROUND

There has been recent concern regarding the increased use of metal-on-metal total hip arthroplasty (MOM-THA) as an alternative to contemporary metal-on-polyethylene total hip arthroplasty (MOP-THA), and the choice remains controversial. We performed a meta-analysis to evaluate and compare metal ion concentrations, complications, reoperation rates, clinical outcomes and radiographic outcomes of MOM-THA and MOP-THA.

METHODS

We performed a systematic review of English and non-English articles identified from MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, PreMEDLINE and HealthSTAR. Metal ion concentrations, complications, reoperation rates and other outcomes of MOM bearings were compared with MOP bearings in THA based on relative risks, mean differences and standardized mean difference statistics.

RESULTS

Eight prospective randomized trials were identified from 1,075 citations. Our results demonstrated significantly elevated erythrocyte, serum and urine levels of metal ions (cobalt and chromium) among patients who received MOM-THA. No significant differences in titanium concentrations or total complication or reoperation rates were found between MOM-THA and MOP-THA. Clinical function scores and radiographic evaluations were similar between the two groups.

CONCLUSIONS

This analysis found insufficient evidence to identify any clinical advantage of MOM-THA compared with MOP-THA. Although cobalt and chromium concentrations were elevated after MOM-THA, there were no significant differences in total complication rates (including all-case mortality) between the two groups in the short- to mid-term follow-up period. The MOM bearing option for THA should be used with caution.

Put your right hip in, put your right hip out

Hip replacement is one of the most common surgical procedures in the United States. Among the multiple reasons that joints degenerate, arthritis leads as a cause of hip pain and failure. Currently, most artificial joints wear out after 10 to 20 years, potentially necessitating another surgery. Total hip arthroplasty (or total hip replacement) involves replacing the femoral neck and femoral head. Devices are held in place using either cement, cementless, or hybrid procedures. Although it occurs in fewer than 1% of procedures, infection can be devastating and lead to the need for multiple surgeries. Today, several options are available when hip replacement is needed. Minimally invasive surgery (MIS) employs the same procedures and materials used in conventional hip surgery but results in less soft-tissue dissection. MIS anterior-hip arthroplasty is a variant of MIS that shortens recovery time. Hip resurfacing spares the femoral head and is generally viewed as a more complicated procedure that may be more appropriate for younger, more active patients. Computed-assisted surgery may allow better positioning of the acetabular component of the prosthesis. Two developing issues related to devices used for hip replacement are device recall and device registries.