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Women in Charnley class C fail to improve in mobility to a higher degree after total hip replacement
Max Gordon1, Paolo Frumento, Olof Sköldenberg
1Swedish Hip Arthroplasty Register , Gothenburg.
Insights
The Charnley classification effectively predicts health-related quality of life after total hip replacement. Women in class C showed poorer outcomes, highlighting the need for tailored attention, especially in mobility improvements.
Area of Science:
- Orthopedic Surgery
- Health Outcomes Research
Background:
- The Charnley comorbidity classification (Classes A, B, C) predicts health-related quality of life (HRQoL) after total hip replacement (THR).
- Interactions between Charnley class, sex, and age, and the grouping of classes A and B, remain unclear.
Purpose of the Study:
- To investigate the interactions between Charnley class, sex, and age on HRQoL after THR.
- To determine if Charnley classes A and B should be grouped.
Main Methods:
- A nationwide cohort from the Swedish Hip Arthroplasty Register (2008-2010) undergoing primary osteoarthritis THR was analyzed.
- Health-related quality of life (HRQoL) was assessed using the EQ-5D index and EQ VAS.
- Preoperative HRQoL, pain, and prior contralateral hip surgery were used to control for confounding factors.
Main Results:
- Women in Charnley class C reported poorer EQ-5D outcomes compared to men.
- This disparity was primarily driven by lower mobility improvement rates in women (40%) versus men (50%).
- Age did not demonstrate interaction with Charnley class, and the classification performed best without altering its structure.
Conclusions:
- The self-administered Charnley classification should be utilized in its complete form.
- Special consideration for women within Charnley class C is warranted, particularly regarding mobility outcomes.
Background:
The Charnley comorbidity classification organizes patients into 3 classes: (A) 1 hip involved, (B) 2 hips involved, and (C) other severe comorbidities. Although this simple classification is a known predictor of health-related quality of life (HRQoL) after total hip replacement (THR), interactions between Charnley class, sex, and age have not been investigated and there is uncertainty regarding whether A and B should be grouped together.
Methods:
We selected a nationwide cohort of patients from the Swedish Hip Arthroplasty Register operated with THR due to primary osteoarthritis between 2008 and 2010. For estimation of HRQoL, we used the generic health outcome questionnaire EQ-5D of the EuroQol group. This consists of 2 parts: the EQ-5D index and the EQ VAS estimates. We modeled the EQ-5D index and the EQ VAS against the self-administered Charnley classification. Confounding was controlled for using preoperative HRQoL values, pain, and previous contralateral hip surgery.
Results:
We found that women in class C had a poorer EQ-5D outcome than men. This effect was mostly due to the fact that women failed to improve in the mobility dimension; only 40% improved, while about 50% of men improved. Age did not interact with Charnley class. We also found that the classification performed best without splitting or aggregating classes.
Interpretation:
Our results suggests that the self-administered Charnley classification should be used in its full capacity and that it may be interesting to devote special attention to women in Charnley class C.
