Short-term clinical and radiological results of two different design metaphyseal fitting femoral stems in total hip arthroplasty: a prospective, randomized trial

Do all short stem types restore biomechanical parameters of the hip? Comparison according to femoral neck osteotomy levels

PURPOSE

There is no consensus on ideal short femoral stem design. A classification system proposed by Feyen and Shimmin divides short stems in two types according to femoral neck osteotomy levels: subcapital (IIIA) and standard (IIIB). The study aims to determine which design type is more successful in restoring native biomechanical parameters and whether stem type has an impact on clinical results.

METHODS

In this retrospective comparative study, patients that have undergone short stem hip arthroplasty were evaluated according to stem types: type IIIA (n = 52, 66.7%) (Mathys Optimys) and IIIB (n = 26, 33.3%) (Implantcast Aida and Smith & Nephew SMF). Pelvis X-rays were assessed in terms of femoral neck length, horizontal and vertical hip centres of rotation, horizontal and vertical femoral offsets, abductor lever arm lengths, leg lengths, and stem-shaft angles. Improvement in Harris hip scores, differences between post-operative and pre-operative measurements, and stem-shaft angles were evaluated and compared between two groups.

RESULTS

Mean femoral neck resection (8.27 ± 6.68 mm in IIIA and 15 ± 6.33 mm in IIIB) was significantly different between both groups (p < 0.001). Harris hip scores were increased at post-operative six months in both groups with no difference (84.4 ± 6.4 and 84.6 ± 5.5, p = 0.4). The absolute values of differences between pre-operative and post-operative horizontal centres of rotation (p = 0.63), vertical centers of rotation (p = 0.75), horizontal femoral offsets (p = 0.78), vertical femoral offsets (p = 0.83), abductor lever arm distances (p = 0.63), and leg length (p = 0.21) measurements were not different between both groups. Stem positions were both varus with no statistically significant difference between groups (p = 0.14).

CONCLUSION

We found no difference regarding restoration of biomechanical parameters between short stem designs with different levels of neck osteotomy. Additionally, short stem can mostly result in varus component positioning regardless of the level of neck osteotomy.

Increased stability of short femoral stem through customized distribution of coefficient of friction in porous coating

Stress shielding and aseptic loosening are complications of short stem total hip arthroplasty, which may lead to hardware failure. Stems with increased porosity toward the distal end were discovered to be effective in reducing stress shielding, however, there is a lack of research on optimized porous distribution in stem's coating. This study aimed to optimize the distribution of the coefficient of friction of a metaphyseal femoral stem, aiming for reducing stress shielding in the proximal area. A finite element analysis model of an implanted, titanium alloy short-tapered wedge stem featuring a porous coating made of titanium was designed to simulate a static structural analysis of the femoral stem's behavior under axial loading in Analysis System Mechanical Software. For computational feasibility, 500 combinations of coefficients of friction were randomly sampled. Increased strains in proximal femur were found in 8.4% of the models, which had decreased coefficients of friction in middle medial areas of porous coating and increased in lateral proximal and lateral and medial distal areas. This study reported the importance of the interface between bone and middle medial and distal lateral areas of the porous coating in influencing the biomechanical behavior of the proximal femur, and potentially reducing stress shielding.

Clinical Significance of Protective Motivation Intervention Nursing on Functional Recovery of Patients after Hip Arthroplasty

Objective

To explore the clinical significance of protective motivation intervention nursing on functional recovery of patients after hip arthroplasty.

Methods

Sixty patients after hip arthroplasty treated in our hospital from February 2019 to April 2021 were selected. The patients were randomly divided into the control group and the research group. The routine nursing mode was adopted in the control group, and the protective motivation intervention nursing mode was adopted in the research group. Nursing satisfaction, FIM score, Harris hip function score, WOMAC score, Barthel index score, and quality of life score were compared between the two groups.

Results

The nursing satisfaction of the research group was higher than that of the control group, and there are statistically significant differences between the groups (P < 0.05). The FIM scores of the research group at discharge and 1 month, 3 months, and 6 months after discharge were significantly higher than those in the control group. The Harris hip function score of the research group was significantly higher than that of the control group at discharge and 1 month, 3 months, and 6 months after discharge. The WOMAC scores of the research group at discharge and 1 month, 3 months, and 6 months after discharge were significantly lower than those in the control group, and the difference was statistically significant (P < 0.05). The scores of the Barthel index at discharge and 1 month, 3 months, and 6 months after discharge in the research group were significantly higher than those in the control group. The scores of physiological function, psychological function, social function, and health self-cognition in the research group were significantly lower than those in the control group, and the difference was statistically significant (P < 0.05).

Conclusion

The nursing model of protective motivation intervention for patients after hip arthroplasty can effectively improve the function of hip joint, improve the quality of life, promote the establishment of harmonious nurse-patient relationship, and play a positive role in improving the prognosis of patients.

Effect of Rehabilitation Nursing under the Guidance of the Health Action Process Approach Model on Perioperative Nursing Effect of Artificial Hip Arthroplasty: Effect on Promoting Quality of Life and Postoperative Rehabilitation

Objective

To explore the influence of rehabilitation nursing under the guidance of Health Action Process Approach (HAPA) model on the perioperative nursing effect of artificial hip replacement and to analyze the effect of this nursing model on the quality of life and postoperative rehabilitation of patients undergoing artificial hip replacement.

Methods

A total of 200 patients with hip arthroplasty treated in our hospital from January 2019 to July 2021 were enrolled. The patients were randomly assigned into the control group and study group. The former received routine nursing, and the latter received rehabilitation nursing under the guidance of the HAPA model. Nursing satisfaction, pain score, Harris hip function score, timed stand-up-walk test, MBI score, and quality of life score were compared.

Results

First of all, we compared the nursing satisfaction. In the study group, 86 cases were very satisfied, 8 cases were satisfied, and 6 cases were general; the satisfaction rate was 100%. In the control group, 48 cases were very satisfied, 22 cases were satisfied, 12 cases were general, and 18 cases were dissatisfied; the satisfaction rate was 82.0%. The nursing satisfaction in the study group was higher compared to that in the control group (P < 0.05). Secondly, we compared the pain scores. Before nursing, there exhibited no significant difference (P > 0.05). After nursing, the pain score of the two groups increased. Moreover, the pain score of the study group at discharge and 1 month, 3 months, and 6 months after operation was lower compared to that of the control group (P < 0.05). Before nursing, there exhibited no significant difference in the Harris hip joint function score (P > 0.05). After nursing, the Harris hip function score increased. Furthermore, the Harris hip function score of the study group at discharge and 1 month, 3 months, and 6 months after operation was higher compared to that of the control group (P < 0.05). In terms of the timed stand-up-walking test, there exhibited no significant difference before nursing (P > 0.05). After nursing, the time of the timed stand-up-walk test in both groups decreased. And the timed stand-up-walk test at discharge and 1 month, 3 months, and 6 months after operation in the study group was lower compared to that in the control group (P < 0.05). Compared with the MBI scores, there exhibited no significant difference before nursing (P > 0.05). After nursing, the MBI scores increased. Of note, the MBI scores of the study group at discharge and 1 month, 3 months, and 6 months after operation were higher compared to those of the control group (P < 0.05). Finally, we compared the scores of life quality. Before nursing, there exhibited no significant difference (P > 0.05). After nursing, the scores of life quality decreased. The scores of physiological function, psychological function, social function, and health self-cognition in the study group were lower compared to those in the control group (P < 0.05).

Conclusion

The perioperative rehabilitation nursing program of artificial hip replacement for the elderly based on the HAPA model is feasible, which can effectively enhance the functional recovery of hip joint, promote the ability of self-care of daily life, relieve pain and anxiety, and help to achieve dynamic balance and gait stability in the early stage. The rehabilitation program is better than routine nursing. As a new social cognitive model, the HAPA model is applied to the rehabilitation nursing environment of hip replacement from the aspect of social cognitive behavior, which can help to enhance the rehabilitation behavior of elderly patients, playing an important role in the rehabilitation effect of perioperative nursing.