An estimated 40% of total costs from a total hip arthroplasty (THA) episode are accrued from post-discharge services. With that in mind, Austin et al. embarked on a randomized controlled trial comparing outcomes among two groups of primary THA patients: those who followed a 10-week self-directed home exercise regimen (n=54) and those who received a combination of in-home and outpatient physical therapy (PT) for 10 weeks (n=54). The results were published in the April 19, 2017 edition of The Journal of Bone & Joint Surgery.
At 1 month and 6 to 12 months after surgery, patients in both groups showed significant preoperative-to-postoperative improvements in function as measured by all administered instruments (Harris Hip Score, WOMAC Index, and SF-36 Physical Health Survey). However, there was no difference in any of the measured functional outcomes between the two groups.
In addition, a total of 30 patients (28%) crossed over between groups: 20 (37%) from the formal physical therapy group and 10 (19%) from the home exercise group. The 10 patients who crossed over from home exercise to formal PT were not meeting progress goals; they tended to be older and had worse preoperative function than those in that cohort who did not cross over.
So, while this study provides evidence that unsupervised home exercise can be as effective as a structured rehabilitation program for most patients, the authors say the following patient characteristics might be indications for a referral to formal PT:
- Older age
- Poorer preoperative function
- Severe preoperative gait imbalance
- Postoperative neurological complications
- Expectations for quick return to high-level activity
An estimated 7 million people living in the US have undergone a total joint arthroplasty (TJA), and the demand for total hip arthroplasty (THA) and total knee arthroplasty (TKA) will almost certainly increase during the next 15 years. But how many people can expect to have an additional TJA after having a first one?
That’s the question Sanders et al. address in their historical cohort study, published in the March 1, 2017 edition of The Journal of Bone & Joint Surgery. They followed more than 4,000 patients who underwent either THA or TKA between 1969 and 2008 to assess the likelihood of those patients undergoing a subsequent, non-revision TJA.
Here’s what they found:
- Twenty years after an initial THA, the likelihood of a contralateral hip replacement was 29%.
- Ten years after an initial THA, the likelihood of a contralateral knee replacement was 6%, and the likelihood of an ipsilateral knee replacement was 2% at 20 years.
- Twenty years after an initial TKA, the likelihood of a contralateral knee replacement was 45%.
- After an initial TKA, the likelihood of a contralateral hip replacement was 3% at 20 years, and the likelihood of an ipsilateral hip replacement was 2% at 20 years.
In those undergoing an initial THA, younger age was a significant predictor of contralateral hip replacement, and in those undergoing an initial TKA, older age was a predictor of ipsilateral or contralateral hip replacement.
The authors conclude that “patients undergoing [THA] or [TKA] can be informed of a 30% to 45% chance of a surgical procedure in a contralateral cognate joint and about a 5% chance of a surgical procedure in noncognate joints within 20 years of initial arthroplasty.” They caution, however, that these findings may not be generalizable to populations with more racial or socioeconomic diversity than the predominantly Caucasian population they studied.
Hip dislocation is one of the most common perioperative complications of total hip arthroplasty (THA). The latest “Case Connections” article examines an often-overlooked spinal basis for THA dislocations, 2 cases of dual-mobility hip-bearing dissociations during attempted closed reduction for post-THA dislocations, and a unique application of Ilizarov distraction to treat a chronic post-THA dislocation.
The springboard case report, from the February 22, 2017, edition of JBJS Case Connector, describes the case of a 63-year-old woman who had experienced 4 anterior dislocations in less than 3 years after having her left hip replaced. Each dislocation was accompanied by lower back pain, and the patient also reported substantial pain in the contralateral hip. The authors emphasize the importance of recognizing pelvic retroversion and sagittal spinal imbalance before performing total hip arthroplasty.
Two additional JBJS Case Connector case reports summarized in the article focus on:
- The risks of performing closed reduction on patients with a dislocated dual-mobility hip design.
- A unique application of Ilizarov distraction to lengthen soft tissues for femoral-component reduction in a patient with a chronically dislocated hip replacement.
While closed reduction with the patient under sedation is a frequently employed first-line tactic that is often successful for dislocated THAs, these 3 cases show that creative surgical interventions may be necessary for optimal outcomes in patients with “complicated” hips and/or recurrent dislocations.
Single-anesthetic bilateral total hip arthroplasty (THA) has had a historically high perioperative complication profile. However, a matched cohort study by Houdek et al. in the January 4, 2017 edition of JBJS comparing single-anesthetic versus staged bilateral THA over four years found no significant differences between the two procedures in terms of:
- Risks of revision, reoperation, or complications (including DVT/PE, dislocation, periprosthetic fracture, and infection; see graph, where blue line represents single-anesthetic and red line indicates staged)
- Perioperative mortality
- Discharge to home versus rehab
The single-anesthetic group (94 patients, 188 hips) experienced shorter total operating room time and hospital length of stay than the matched cohort, and consequently the single-anesthetic approach lowered the relative total cost of care by 27%.
While the Mayo Clinic authors concede the potential for selection bias in this study (e.g., there was no standardized protocol for determining eligibility for inclusion in either group), they say that they currently consider single-anesthetic bilateral THA for patients with bilateral coxarthrosis who are <70 years of age, relatively healthy, and/or have bilateral hip contractures that would make rehabilitation difficult.
In the January 4, 2017 issue of The Journal, Swart et al. provide a well-done Markov decision analysis on the cost effectiveness of three treatment options for femoral neck fractures in patients between the age of 40 and 65: open reduction and internal fixation (ORIF), total hip arthroplasty (THA), and hemiarthroplasty. Plugging the best data available from the current orthopaedic literature into their model, the authors estimated the threshold age above which THA would be the superior strategy in this relatively young population.
For patients in this age group, traditional thinking has been to perform ORIF in order to “save” the patient’s native hip and avoid the likelihood of later revision arthroplasty. However, in this analysis THA emerges as a cost-effective option in otherwise healthy patients >54 years old, in patients >47 years old with mild comorbidity, and in patients >44 years old with multiple comorbidities.
On average, both THA and ORIF have similar outcomes across the age range analyzed. But ORIF with successful fracture healing yields slightly better outcomes and considerably lower costs than THA, whereas patients whose fracture does not heal with ORIF have notably worse outcomes than THA patients. This finding supports my personal bias that anatomical reduction and biomechanically sound fixation must be achieved in this younger population with displaced femoral neck fractures. The analysis confirmed that, because of poor functional outcomes with hemiarthroplasty in this population, hemiarthroplasty should not be considered. Poor hemiarthroplasty outcomes are likely related to the mismatch between the metal femoral head and the native acetabular cartilage, leading to fairly rapid loss of the articular cartilage and subsequent need for revision.
This analysis by Swart et al. provides very valuable data to discuss with younger patients and families when engaging in shared decision making about treating an acute femoral neck fracture. In my experience, most patients in this age group prefer to “keep” their own hip whenever possible, which puts the onus on the surgeon to gain anatomic reduction and biomechanically sound fixation with ORIF.
Marc Swiontkowski, MD
As an end-of-year thank-you to the orthopaedic community, we’re offering limited-time full-text access to the five most-read JBJS articles of 2016. The fact that several of these most-read articles were published prior to 2016 is testament to the durable utility of orthopaedic research published in The Journal of Bone & Joint Surgery.
- Bariatric Orthopaedics: Total Hip Arthroplasty in Super-Obese Patients
- Antibiotic-Impregnated Cement Spacers for the Treatment of Infection Associated with Total Hip or Knee Arthroplasty
- The Surgical Management of Chronic Tophaceous Gout
- Rotator Cuff Tear Arthropathy: Evaluation, Diagnosis, and Treatment
- An Algorithmic Approach to the Management of Recurrent Lateral Patellar Dislocation
“Necessity is the mother of invention.” In recent years, the demand for total hip, total knee, and unicompartmental knee arthroplasty has grown substantially. However, with limited resources and health-care budgets, there is a need to reduce hospital costs. To that end, a number of surgeons have begun to perform these procedures on an outpatient basis.
Indeed, as the demand for joint replacements grows, it will be imperative to improve patient safety and satisfaction while minimizing costs and optimizing the use of health-care resources. In order to accomplish this goal, surgical teams, nursing staff, and physiotherapists will need to work together to discharge patients from the hospital as soon as safely possible, including on the same day as the operation. The development of accelerated clinical pathways featuring a multidisciplinary approach and involving a range of health-care professionals will result in extensive preoperative patient education, early mobilization, and intensive physical therapy.
In the December 2016 issue of JBJS Reviews, Pollock et al. report on a systematic review that was performed to determine the safety and feasibility of outpatient total hip, total knee, and unicompartmental knee arthroplasty. The authors hypothesized that outpatient arthroplasty would be safe and feasible and that there would be similar complication rates, similar readmission and revision rates, similar clinical outcomes, and decreased costs in comparison with the findings associated with the inpatient procedure. The investigators demonstrated that, in selective patients, outpatient total hip, total knee, and unicompartmental knee arthroplasty can be performed safely and effectively.
A major caveat of this well-conducted study, however, is that, like any systematic review, its overall quality is based on the quality of the individual studies that make up the analysis. In this case, the studies included those that lacked sufficient internal validity, sample size, methodological consistency, and standardization of protocols and outcomes. Thus, going forward, there is a need for more rigorous and adequately powered randomized trials to definitively establish the safety, efficacy, and feasibility of outpatient hip and knee arthroplasty.
Thomas A. Einhorn, MD
Editor, JBJS Reviews
Every month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.
This month, James Ninomiya, MD, MS, lead author of the September 21, 2016 Specialty Update on Hip Replacement, selected the five most clinically compelling findings from among the nearly 70 studies summarized in the Specialty Update.
–A meta-analysis found no differences in short- and medium-term implant survivorship among the following three bearing combinations used in THA patients younger than 65 years of age: ceramic on ceramic, ceramic on highly cross-linked polyethylene, and metal on highly cross-linked polyethylene.1
Insight into Aseptic Loosening
–Pathogen-associated molecular patterns (“endotoxins”) on particulate wear debris may be partially responsible for aseptic loosening. An in vitro/in vivo study found that macrophages that did not express the pathogen-associated molecular pattern receptor called TIRAP/Mal had significantly diminished secretion of inflammatory proteins. Patients with a genetic polymorphism suppressing that receptor exhibited decreased osteolysis during in vivo experiments. This suggests that some patients may be genetically more prone to aseptic loosening.
THA in Patients with RA
–A systematic review/meta-analysis of patients who were and were not taking a TNF-α inhibitor for rheumatoid arthritis prior to hip replacement found that those taking the drug had an increased risk of perioperative infection, with an odds ratio of 2.47.2 These results suggest that in order to decrease the risk of perioperative infections, it may be prudent to discontinue these drugs in advance of proposed joint replacement surgery.
Delaying THA for Femoral Head Osteonecrosis
–A systematic review/meta-analysis of patients with femoral head osteonecrosis concluded that injection of autologous bone marrow aspirate containing mesenchymal stem cells during core decompression was superior by a factor of 5 to core decompression alone in preventing collapse of the femoral head and delaying conversion to THA.3 This information may lead to new treatment paradigms for osteonecrosis.
Preventing Post-THA Dislocations
–A systematic review/meta-analysis that included more than 1,000 patients who underwent THA with a posterior or anterolateral approach found similar dislocation rates among those who were and were not given post-procedure restrictions in motion or activity.4 This suggests that the use of traditional hip precautions may not be necessary, and in fact may impede the rate of recovery following joint replacement surgery.
- Wyles CC, Jimenez-Almonte JH, Murad MH, Norambuena-Morales GA, Cabanela ME, Sierra RJ, TrousdaleRT. There are no differences in short- to mid-term survivorship among total hip-bearing surface options: a network meta-analysis. Clin Orthop Relat Res. 2015 Jun;473(6):2031-41. Epub 2014 Dec 17.
- Goodman SM, Menon I, Christos PJ, Smethurst R, Bykerk VP. Management of perioperative tumour necrosis factor α inhibitors in rheumatoid arthritis patients undergoing arthroplasty: a systematic review and meta-analysis. Rheumatology (Oxford). 2016 Mar;55(3):573-82. Epub 2015 Oct 7.
- Papakostidis C, Tosounidis TH, Jones E, Giannoudis PV. The role of “cell therapy” in osteonecrosis of the femoral head. A systematic review of the literature and meta-analysis of 7 studies. Acta Orthop. 2016 Feb;87(1):72-8. Epub 2015 Jul 29.
- Van der Weegen W, Kornuijt A, Das D. Do lifestyle restrictions and precautions prevent dislocation after total hip arthroplasty? A systematic review and meta-analysis of the literature. Clin Rehabil. 2016 Apr;30(4):329-39. Epub 2015 Mar 31.
The incidence of primary total knee and hip arthroplasty is increasing steadily. While the success rates of these procedures are remarkable, failures do occur, and periprosthetic joint infection is the leading culprit in such failures. The standard treatment when deep infection strikes is a two-stage revision.
On Monday, November 14, 2016 at 8:00 PM EST, The Journal of Bone & Joint Surgery (JBJS) will host a complimentary webinar that examines prognostic factors affecting the success of two-stage revision arthroplasty for infected knees and hips.
- Tad M. Mabry, MD, coauthor of a matched cohort study in JBJS, will examine the impact of morbid obesity on the failure of two-stage revision TKA.
- JBJS author Antonia F. Chen, MD, will discuss results from a retrospective study that revealed an association between positive cultures at the time of knee/hip component reimplantation and the risk of subsequent treatment failure.
Moderated by JBJS Deputy Editor Charles R. Clark, MD, the webinar will include additional perspectives from two expert commentators—Daniel J. Berry, MD and Andrew A. Freiberg, MD. The last 15 minutes will be devoted to a live Q&A session, during which the audience can ask questions of all four panelists.
Seats are limited, so register now!
Many orthopaedists wonder whether—or under what circumstances—arthroscopy confers any clinical benefit in treating hip osteoarthritis. A prospective matched-pair analysis by Chandrasekaran et al. in the June 15, 2016 Journal of Bone & Joint Surgery suggests that arthroscopy does not help prevent the eventual conversion to total hip arthroplasty (THA) in hips with Tönnis grade-2 arthritis (moderate narrowing of the joint space with moderate loss of femoral-head sphericity).
The authors compared two-year outcomes from 37 patients with Tönnis grade-2 hip osteoarthritis who had a hip arthroscopy performed with outcomes from matched cohorts of 37 Tönnis grade-0 and 37 grade-1 hips on which arthroscopy was also performed. In all cases, arthroscopy sought to address symptomatic intra-articular hip disorders refractory to nonoperative management. The cohorts were matched to minimize the confounding effects of age, sex, and BMI on the outcomes.
There were no significant differences among the groups with respect to four patient-reported outcome measures (including the modified Harris hip score), VAS pain scores, and patient satisfaction levels. However, Tönnis grade-2 hips had a significantly higher conversion rate to THA compared to the other two matched cohorts. In absolute terms, a subsequent THA was required for 3 hips in the Tönnis grade-0 group, 5 in the Tönnis grade-1 group, and 15 in the Tönnis grade-2 group.
From this finding, the authors conclude that “hip arthroscopy has a limited role as a joint preservation procedure in select patients with Tönnis grade-2 osteoarthritis…Hip arthroscopy can effectively restore the labral seal and address impingement, but patients may continue to experience symptoms associated with the osteoarthritis.”