What Do We Know About Taper Corrosion in Total Hip Arthroplasty?

Mechanically assisted crevice corrosion (MACC) at metal/metal modular junctions in which at least one of the components is fabricated from cobalt-chromium alloy, has reemerged as a potential clinically significant complication in total hip arthroplasty. The clinical manifestation of MACC may include the development of an adverse local tissue reaction (ALTR), similar to what has been described in association with metal-on-metal bearing total hip and resurfacing arthroplasty. The clinical presentation of MACC-associated ALTRs may include pain and possibly late recurrent dislocations. Abnormal metal artifact reduction sequence magnetic resonance images and elevated serum metal levels (cobalt elevations out of proportion to chromium elevations) can be helpful in the diagnosis of these MACC-associated ALTRs.     

Do Conversion Total Hip Arthroplasty Yield Comparable Results to Primary Total Hip Arthroplasty?

Background

The incidence of hip fractures is growing with the increasing elderly population. Typically, hip fractures are treated with open reduction internal fixation, hemiarthroplasty, or total hip arthroplasty (THA). Failed hip fracture fixation is often salvaged by conversion THA. The total number of conversion THA procedures is also supplemented by its use in treating different failed surgical hip treatments such as acetabular fracture fixation, Perthes disease, slipped capital femoral epiphysis, and developmental dysplasia of the hip. As the incidence of conversion THA rises, it is important to understand the perioperative characteristics of conversion THA. Some studies have demonstrated higher complication rates in conversion THAs than primary THAs, but research distinguishing the 2 groups is still limited.

Infection or Allergy in the Painful Metal-on-Metal Total Hip Arthroplasty?

Metal-on-metal articulations are increasingly used in total hip arthroplasty. Patients can be sensitive to metal ions produced by the articulation and present with pain or early loosening. Infection must be excluded. Correct diagnosis before revision surgery is crucial to implant selection and operation planning. There is no practical guide in the literature on how to differentiate between allergy and infection in a painful total hip arthroplasty. We present the history, clinical findings and hip scores, radiology, serology, hip arthroscopy and aspirate results, labeled white cell scan, revision-hip findings, histology and clinical results of a typical patient with a hypersensitivity response to a metal-on-metal hip articulation, and how results differ from patients with an infected implant. A practical scheme to investigate patients with a possible hypersensitivity response to an implant is presented.     

What Is the Learning Curve for the Anterior Approach for Total Hip Arthroplasty?

Background

There are many factors that may affect the learning curve for total hip arthroplasty (THA) and surgical approach is one of these. There has been renewed interest in the direct anterior approach for THA with variable outcomes reported, but few studies have documented a surgeon’s individual learning curve when using this approach.

Questions/purposes

(1) What was the revision rate for all surgeons adopting the anterior approach for placement of a particular implant? (2) What was the revision rate for surgeons who performed > 100 cases in this fashion? (3) Is there a minimum number of cases required to complete a learning curve for this procedure?

Methods

The Australian Orthopaedic Association National Joint Replacement Registry prospectively collects data on all primary and revision joint arthroplasty surgery. We analyzed all conventional THAs performed up to December 31, 2013, with a primary diagnosis of osteoarthritis using a specific implant combination and secondarily those associated with surgeons performing more than 100 procedures. Ninety-five percent of these procedures were performed through the direct anterior approach. Procedures using this combination were ordered from earliest (first procedure date) to latest (last procedure date) for each individual surgeon. Using the order number for each surgeon, five operation groups were defined: one to 15 operations, 16 to 30 operations, 31 to 50 operations, 51 to 100 operations, and > 100 operations. The primary outcome measure was time to first revision using Kaplan-Meier estimates of survivorship.

Results

Sixty-eight surgeons performed 5499 THAs using the specified implant combination. The cumulative percent revision at 4 years for all 68 surgeons was 3% (95% confidence interval [CI], 2.5–3.8). For surgeons who had performed over 100 operations, the cumulative revision rate was 3% (95% CI, 2.0–3.5). It was not until surgeons had performed over 50 operations that there was no difference in the cumulative percent revision compared with over 100 operations. The cumulative percent revision for surgeons performing 51 to 100 operations at 4 years was 3% (95% CI, 1.5–5.4) and over 100 operations 2% (95% CI, 1.2–2.7; hazard ratio, 1.40 [95% CI, 0.7–2.7]; p = 0.33).

Conclusions

There is a learning curve for the anterior approach for THA even when using a prosthesis combination specifically marketed for that approach. We found that 50 or more procedures need to be performed by a surgeon before the rate of revision is no different from performing 100 or more procedures. Surgeons should be aware of this initial higher rate of revision when deciding which approach delivers the best outcome for their patients.     

Chinese Patients' Satisfaction With Total Hip Arthroplasty: What Is Important and Dissatisfactory?

Through validated self-administered questionnaires, we conducted a retrospective investigation in 818 patients (1009 hips) who underwent primary THA, to collect data on overall satisfaction plus satisfaction and importance rating for 16 specific functions and issues. Overall, 8.1% patients were dissatisfied with the surgery. The top 3 important items are pain relief, squatting, and walking. The top 3 dissatisfactory items are jogging, squatting, and rising after squatting. The strongest risk factors for dissatisfaction with walking were pain (6.1 ×), muscle weakness(3.7 ×), and LLD (3.3 ×). The strongest risk factors for dissatisfaction with squatting were low postoperative HHS ROM (3.7 ×) and muscle weakness (2.6 ×). For Chinese patients, ROM, muscle strength and LLD are very important.     

Quantifying Surgeon Work in Total Hip and Knee Arthroplasty: Where Do We Stand Today?

BackgroundPhysician work is a critical component in determining reimbursement for total joint arthroplasty (TJA). The purpose of this study is to quantify the time spent during the different phases of TJA care relative to the benchmarks used by the Centers for Medicare and Medicaid Services.MethodsWe retrospectively reviewed all patients captured in our institutional joint database between January 1, 2014, and December 31, 2018. Four phases of care were assessed: (1) preoperative period following the decision to proceed with TJA and leading to the day before surgery, (2) immediate 24 hours preceding surgery (preservice time), (3) operative time from skin incision to dressing application (intraservice time), and (4) postoperative work including day of surgery and the following 90 days.ResultsA total of 666 procedures were analyzed (379 total hip arthroplasties and 287 total knee arthroplasties). The mean preoperative care coordination, preservice, intraservice, immediate postservice, and 91-day global period times were 21.9 ± 10, 84.1, 114 ± 24, 35, and 150 ± 37 minutes, respectively. Except for a slightly higher preoperative time associated with Medicare coverage (P = .031), there were no differences in the other phases of care by payer type. There were no temporal differences between 2014 and 2017. However, in 2018, there were significant increases in preoperative and intraservice times (6 and 20 minutes, respectively, P < .001) which were accompanied with a significant decrease in postoperative service time (34 minutes, P < .001).ConclusionEven when performing TJA under the most optimal conditions, the overall time has remained stable over the past 5 years and consistent with current benchmarks.     

A Prospective Randomized Clinical Trial in Total Hip Arthroplasty—Comparing Early Results Between the Direct Anterior Approach and the Posterior Approach

Background

We report a prospective randomized study comparing early clinical results between the direct anterior approach (DAA) and posterior approach (PA) in primary hip arthroplasty.

Evidence: What Is It,Where Do We Find It,and How Do We Use It?

The purpose of this paper is to review the history and rationale for evidence-based medicine (EBM). The development of EBM is briefly described, together with the pros and cons of evidence-based research, review techniques, and resources. The current status of EBM with regard to the treatment of overactive bladder (OAB) is also discussed. In short, EBM can be defined as the conscientious, explicit and judicious use of current best evidence to make decisions about the care of individual patients. The four main steps are: (1) formulate a clear question from a patient’s problem, (2) search the literature for relevant clinical articles, (3) evaluate and critically appraise existing evidence for its validity and usefulness, and (4) implement useful findings in clinical practice. The power of the evidence-based approach can be enhanced by the development of techniques such as systematic review and meta-analysis. However, although EBM allows us to use current best evidence to make decisions about patient care, the evidence gained from systematic review and meta-analysis only applies to an “average patient” and is not readily adaptable to issues such as etiology, diagnosis and prognosis.     

Nerve Decompression Surgery After Total Hip Arthroplasty: What Are the Outcomes?

Background

The purpose of our study was to compare (1) muscle strength; (2) pain; (3) sensation; (4) various outcome measurement scales between post-total hip arthroplasty (THA) patients who had a sciatic nerve injury and did or did not receive decompression surgery for this condition; and (5) to compare these findings with current literature.

Should Cannabinoids Be Added to Multimodal Pain Regimens After Total Hip and Knee Arthroplasty?

Background

This study investigated the effects of dronabinol on pain, nausea, and length of stay following total joint arthroplasty (TJA).