Different Designs of Proximal Femoral Stems for Total Hip Arthroplasty: Mid-Term Clinical and Patient-Reported Functional Outcomes

Minimal pre-operative leg length discrepancy as a risk factor of post-operative leg length discrepancy after total hip arthroplasty: a retrospective study of patients with non-traumatic osteonecrosis of the femoral head

BACKGROUND

Leg length discrepancy (LLD) is one of the troublesome complications of total hip arthroplasty (THA). Previously, several risk factors have been suggested, but they were subjected to their inherent limitations. By controlling confounding variables, we hypothesized that known risk factors be re-evaluated and novel ones be discovered. This study aimed to analyze the independent risk factors for LLD after primary THA in patients with non-traumatic osteonecrosis of the femoral head (ONFH).

METHODS

We retrospectively reviewed patients with non-traumatic ONFH who underwent unilateral THA between 2014 and 2021. All patients were operated by one senior surgeon using a single implant. Demographic data, surgical parameters, and radiological findings (pre-operative LLD, Dorr classification, and femoral neck resection) were analyzed to identify the risk factors of ≥ 5 mm post-operative LLD based on radiological measurement and to calculate odds ratios by logistic regression analysis. Post hoc power analysis demonstrated that the number of analyzed patients was sufficient with 80% power.

RESULTS

One hundred and eighty-six patients were analyzed, including 96 females, with a mean age of 58.8 years at the time of initial THA. The average post-operative LLD was 1.2 ± 2.9 mm in the control group and 9.7 ± 3.2 mm in the LLD group, respectively. The LLD group tended to have minimal pre-operative LLD than the control group (-3.2 ± 5.1 mm vs. -7.9 ± 5.8 mm p = 2.38 × 10- 8). No significant difference was found between the groups in age, gender, body mass index, femoral cortical index, and implant size.

CONCLUSION

Mild pre-operative LLD is associated with an increased risk of post-operative LLD after primary THA in patients with ONFH. Thus, surgeons should recognize pre-operative LLD to achieve an optimal outcome and must inform patients about the risk of developing LLD.

Relevant Predictors in the Association Between Patients' Functional Status and Scar Outcomes After Total Hip Arthroplasty

BACKGROUND

We aimed to investigate the relevant predictors in the association between the functional status and the consequences of the persistence of scars in patients with traumatic versus non-traumatic coxarthrosis after total hip arthroplasty (THA).

METHODS

A total of 203 patients undergoing THA after traumatic or non-traumatic coxarthrosis were asked to complete the Mekeres' Psychosocial Internalization Scale (MPIS), in which they self-evaluated on a Likert scale (between one and five) by selecting the rating that corresponded to their personal opinion and the activities of daily living (ADL) form at six months postoperative. The statistical data were processed using the IBM SPSS Statistics software version 22.0 (IBM Corp., Armonk, NY). A combined assessment of the internalization of scars using MPIS and ADL forms after THA allowed for the identification of relevant predictors of the quality of life six months post-surgery in patients with traumatic or non-traumatic coxarthrosis.

RESULTS

Depending on the coxarthrosis etiology (traumatic or non-traumatic), the results were further processed by a univariate ANOVA, considering the independent variables represented by symptoms, the number of surgical procedures, and the postoperative evolution, which are acting on the outcomes of physical functioning (the dependent variable) in the postoperative phase. In the case of the traumatic group, our results suggest that the number of surgical interventions, the ability to internalize scars, and autonomy in terms of body care are predictors of the quality of life. In patients with non-traumatic coxarthrosis, an important role in predicting quality of life is played by the administered treatment and the ability to maintain their autonomy regarding self-hygiene six months post-surgery.

CONCLUSIONS

The predictive regression equation suggests that the quality of life in patients with traumatic coxarthrosis can be predicted by the number of surgical interventions, the administered treatment, the ability to internalize scars, and the autonomy regarding body care activities. On the other hand, for patients with non-traumatic coxarthrosis, an important role in predicting the quality of life is played by the treatment and the ability to maintain autonomy in terms of body hygiene activities.

Femoral stem taper geometry and porous coating in cementless direct anterior primary total hip arthroplasty

Objective

This study aims to compare the clinical outcomes and complications between a fully coated, dual-tapered hip stem versus a proximally coated, triple-tapered hip stem in patients undergoing cementless direct anterior (DA) primary total hip arthroplasty (THA).

Methods

A retrospective analysis was conducted on patients who underwent primary THA with either a fully coated, dual-tapered hip stem or a proximally coated, triple-tapered stem with at least a 1-year follow up. Exclusion criteria included any patients that did not receive either femoral stem, those undergoing bilateral THA, those with a surgical approach other than DA, those with an indication other than osteoarthritis, avascular necrosis (AVN), or femoral neck fracture, and those that had a cemented femoral component. Complications and clinical outcomes were assessed. Statistical analyses were conducted to identify significant differences between the groups.

Results

A total of 95 patients were included in the study. The average ages for the dual-tapered and triple-tapered stem cohorts were 63.6 and 59.5, respectively (p = 0.168). At 1-year follow-up, no significant differences were seen between the groups in terms of ambulatory status, ROM, and patient satisfaction (p = 0.414, p = 0.106, and p = 0.126). 6 (18 %) of the patients receiving the dual-tapered, fully coated hip stem had at least one complication while 8 (13 %) of the triple-tapered, proximally coated hip stem patients did (p = 0.550).

Conclusion

Both hip stem cohorts demonstrated comparable clinical outcomes and complication rates in patients undergoing primary DA THA and we believe that either hip stem may be a reasonable choice for patients. Future studies with larger sample sizes and longer follow-up periods are warranted to validate these findings.