The indications for treating total hip arthroplasty (THA) dislocations by cementing a constrained polyethylene liner into a well-fixed, retained acetabular component at the time of revision are narrow. That’s largely due to concerns about the durability of the resulting acetabular construct. Now, thanks to a study by Brown et al. in the April 3, 2019 issue of JBJS, hip surgeons have some hard data about the long-term outcomes of this approach.
After reviewing 125 cases in which a constrained liner was cemented into a retained, osseointegrated acetabular component during revision THA, with a mean follow-up of 7 years, the authors found that:
- Survivorship free from revision for instability was 86% at 5 years and 81% at 10 years. The cumulative incidence of instability at 7 years was 18%.
- Survivorship free from aseptic acetabular component revision was 78% at 5 years and 65% at 10 years. The most common failure mechanism was dissociation of the constrained liner from the retained component.
- Harris hip scores (HHS) did not improve significantly after revision. This finding is consistent with prior research that shows better post-revision HHS scores in patients whose revisions include the entire acetabular component.
- Position of the retained cup did not affect implant survivorship or risk of dislocation.
The authors mention alternative strategies for reducing the risk of dislocation after revision THA, such as the use of large-diameter heads and dual-mobility constructs. Still, they conclude that this constrained-liner approach, in the setting of a relatively well-positioned acetabular component, is a viable and durable THA revision option, especially for those “with a compromised abductor mechanism, recurrent instability, [and] a well-fixed and well-positioned acetabular component, for whom an acetabular revision would not be tolerated.”
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.
The recently launched JBJS Knee Spotlight offers highly relevant and potentially practice-changing knee content from the most trusted source of orthopaedic information.
Here are the five JBJS articles to which you will have full-text access through the Knee Spotlight during the month of February 2017:
Comparison of Highly Cross-Linked and Conventional Polyethylene in Posterior Cruciate-Substituting Total Knee Arthroplasty in the Same Patients
What’s New in Adult Reconstructive Knee Surgery
Hinged External Fixation in the Treatment of Knee Dislocations: A Prospective Randomized Study
A Randomized, Controlled, Prospective Study Evaluating the Effect of Patellar Eversion on Functional Outcomes in Primary Total Knee Arthroplasty
Comparison of Functional Outcome Measures After ACL Reconstruction in Competitive Soccer Players: A Randomized Trial
Knee studies offered on the JBJS Knee Spotlight will be updated monthly, so check the site often.
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 ability of the small and complexly connected wrist bones to function properly supports everything from activities of daily living and work to the creation of art and music. This month’s “Case Connections” article explores wrist dislocations that required open reduction and some form of fixation. Considering the high degree of anatomical derangement and instability in these cases, the outcomes were remarkably good, thanks to carefully planned and executed orthopaedic interventions.
The springboard case, from the July 27, 2016 edition of JBJS Case Connector, describes the treatment of a 47-year-old male bicyclist who was hit by a car and sustained complete scaphoid and lunate dislocations. Three additional JBJS Case Connector case reports summarized in the article focus on:
- a 22-year-old man who sustained volar dislocation of the hamate and scapholunate dissociation as a result of a motor-vehicle accident
- a 30-year-old man who experienced volar dislocation of the lunate as well as of the proximal pole of a fractured scaphoid after falling from a height of 15 feet with his outstretched hand and wrist in extension
- a 25-year-old man who fell from a height of 20 feet and dislocated the hand and wrist dorsally about the scaphoid and lunate.
Anatomical reduction frequently required both dorsal and volar exposures. In one case, a successful outcome was achieved without addressing ligamentous injuries.
The November 25, 2015 “Case Connections” looks at four JBJS Case Connector cases involving injuries to the cervical spine in which the outcomes were about as good as anyone could have wished, considering the potential for disaster. Two of the cases required surgical intervention to achieve the positive outcomes, but the outcomes in the other two cases were remarkably positive without surgery.
While these four cases of cervical spine injury had relatively “happy endings,” orthopaedic surgeons and other health-care professionals treating patients with any suspected spine injury are trained to proceed with the utmost care and caution out of concern for devastating neurological sequelae. Watchful waiting under close medical scrutiny is sometimes warranted, but many cases of cervical fracture, dislocation, or instability call for operative stabilization to reduce the risk of life-changing or life-threatening consequences. The potential seriousness of surgical complications when operating on the spine must also be recognized.