Harnessing modifiable intraoperative factors—what decisions should surgeons make to improve postoperative stability?

The spinopelvic relationship in total hip arthroplasty

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The risk of instability, impingement, and dislocation is multifaceted in total hip arthroplasty (THA). In Part 1 of the series, we discussed the nonmodifiable patient risk factors that come into play, including demographics, THA indications, and associated pathologies like lumbar spine diseases, that may affect the hip-spine relationship. Following the critical consideration of these characteristics, Part 2 of the series guides us through the preoperative planning stage, when spinopelvic parameters should be considered via radiographic imaging of the patient in different positions, ie, standing and sitting, to better template the orientation of the implant.

In Part 3 of our three-part series, George Grammatopoulos from The Ottawa Hospital emphasizes the need for a holistic approach encompassing all parameters that may influence clinical outcomes. He is a pioneering advocate in the importance of attention to detail intraoperatively and provides us with his list of key surgical decisions and safety checks to perform during the THA procedure. Understanding the surgical factors that influence clinical safety and performance outcomes, along with the role of spinopelvic parameters, will help heighten surgical acumen and minimize the risk of postoperative instability.

An emphasis on the problem—instability remains

In Part 1 and Part 2 of this series on spinopelvic parameters in total hip arthroplasty (THA), we discuss the prevalence and incidence of postoperative instability and how it is still a common complication despite many applied strategies for improvement. Besides the obvious risks of revision surgery due to instability, the postoperative quality of life of the patient can be dramatically influenced by the related complications. Impingement is undoubtedly painful and uncomfortable for the patient, and the constant concern that a dislocation could happen at any time is not easy to manage. Patient-reported outcomes from over 1,000 patients with dislocation were analyzed in a 2022 cross-sectional study in the Danish Hip Arthroplasty Register and matched 1:2 to control patients without dislocation. Applying the established EQ-5D and HOOS patient questionnaires, the study revealed that patients who experienced dislocation consistently reported reduced health and hip-related quality-of-life indicators compared to the controls, even 5 years after the latest dislocation. Twenty percent of the patients with dislocation said they would not undergo the hip replacement surgery again compared to only 7% of controls [1]. This is too high a degree of dissatisfaction and lack of confidence in THA from patients who sustained a dislocation.

Another recent 2022 analysis from the UK Clinical Practice Research Datalink database had similar findings on the quality of life and burden of THA dislocation, with the EQ-5D and Oxford Hip Scores reported as being worse in patients with dislocation. Additionally, the economic burden was shown to be immense. Dislocation led to increased healthcare costs and use of resources, with patients often requiring multiple surgeries. Direct medical costs at 2 years were around 150% higher for patients with dislocation, and these costs increased to around 450% for patients with multiple closed reductions and a revision surgery [2]. Collectively these studies underscore the long-term impact of dislocation on patient well-being, as well as the never-ending balance in maintaining excellence in patient care while decreasing economic burden.

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Highlighting the remaining instability
Improved disclocation rates?
Intraoperative strategies during THA surgery
Towards anterior approach adoption
Patient-specific spinopelvic evaluation
Bearing size impact on dislocation rate
Hip reconstruction and trial liners use
Big data and future technology
Conclusions

Contributing experts

This series of articles was created with the support of the following specialists (in alphabetical order):

This article was written by Greta Thompson-Steckel, AO Innovation Translation Center, Clinical Evidence, Switzerland.

References

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* AO Surgery Reference