Low rate of early periprosthetic fractures in cementless short-stem total hip arthroplasty using a minimally invasive anterolateral approach

Risk Factors for Periprosthetic Femoral Fractures After Cementless Total Hip Arthroplasty

BACKGROUND

The present study aimed to identify the risk factors of periprosthetic femoral fracture (PFF) after cementless total hip arthroplasty and rank them based on importance.

METHODS

The age, sex, body mass index (BMI), osteoporosis, canal flare index (CFI), canal bone ratio (CBR), canal calcar ratio (CCR), stem design, and stem canal fill ratio (P1, P2, P3, and P4) of the proximal femoral medullary cavity of 111 total hip arthroplasty patients who had PFF and 388 who did not have PFF were analyzed. Independent-samples student t-tests were used for continuous variables, and Chi-square tests were used for categorical variables. The importance rankings of influencing factors were assessed using a random forest algorithm. Dimensionally reduced variables were then incorporated into a binary logistic regression model to determine the PFF-related risk factors.

RESULTS

The mean age, BMI, CBR, CCR, and incidence of osteoporosis were higher in cases of PFF (all P < .001), while the mean CFI, P1, P2, P3, and P4 were lower in cases of PFF (P < .001, P = .033, P = .008, P < .001, and P < .001, respectively). Additionally, the stem design was also statistically associated with PFF (P < .001). Multivariate logistic regression revealed that advanced age, higher BMI, osteoporosis, stem design, lower CFI, higher CBR, higher CCR, lower P1, lower P2, lower P3, and lower P4 were the risk factors of PFF (P < .001, P < .001, P < .001, P < .001, P < .001, P = .010, P < .001, P = .002, P < .001, P < .001, and P = .007, respectively). The ranked importance of the risk factors for PFF was P3, CFI, osteoporosis, CBR, age, P4, P1, stem design, CCR, BMI, and P2.

CONCLUSIONS

Lower P3, lower CFI, osteoporosis, higher CBR, advanced age, lower P4, lower P1, stem design, higher CCR, higher BMI, and lower P2 increased the risk of PFF.

Cementless short stem total hip arthroplasty in patients older than 75 years: is it feasible?

BACKGROUND

In recent years, the indication for cementless short stem total hip arthroplasty (THA) has been widened to elderly patients as they might profit by the advantages of the short-curved implant design as well. Therefore, this study was conducted to evaluate the clinical and radiological outcome of a cementless short stem in elderly patients (≥ 75 years) compared to a young control group (≤ 60 years).

METHODS

A retrospective cohort of 316 THAs performed between 2014 and 2017 was prospectively examined. In all patients a cementless, curved short stem and press-fit cup (Fitmore® stem; Allofit®/-S cup; both ZimmerBiomet, Warsaw, IN, USA) were implanted via a minimally-invasive anterolateral approach. Clinical and radiological outcome as well as rate of complications and revision were assessed.

RESULTS

In total, 292 patients have been included for analysis of complications and revisions (Øfollow-up: 4.5 years) and 208 patients for clinical and radiological outcome (Øfollow-up: 4.4 years). Complication rate was significantly increased in elderly patients (13.7% vs. 5.8%, p = 0.023), while the revision rate was increased without statistical significance (5.2% vs. 2.2%, p = 0.169). Periprosthetic fractures occurred significantly higher in the elderly patients (5.2% vs. 0.7%; p = 0.026). Both groups showed a comparable clinical outcome in the Harris Hip Score (93.7 vs. 91.9; p = 0.224), Oxford Hip Score (44.5 vs. 43.7; p = 0.350), Forgotten Joint Score (81.7 vs. 81.5; p = 0.952) and WOMAC (7.4 vs. 9.3; p = 0.334).

CONCLUSION

Cementless short stem total hip arthroplasty shows a comparable clinical and radiological outcome in patients over 75 years of age compared to younger patients under 60 years of age. However, cementless shorts stem THA shows an increased rate of overall complications and periprosthetic fractures in elderly patients over 75 years of age. Cemented fixation of the femoral component should be considered in patients over 75 years of age.

LEVEL OF EVIDENCE

III Case-controlled study.

TRIAL REGISTRATION

Observational study without need for trial registration due to ICMJE criteria.

Short stem hip arthroplasty with the optimys prosthesis is a safe and effective option for obese patients: a mid-term follow-up multicenter study

INTRODUCTION

Short stems are a valuable option in young patients undergoing total hip arthroplasty (THA) because of their bone stock preserving properties facilitating revision hip arthroplasty. Although the effect of obesity on conventional THA is well studied, data about short stem THA in obese patients are lacking. Therefore, this study aimed to investigate the influence of obesity on complications, revisions, and outcome after short stem THA.

MATERIALS AND METHODS

This multicenter, observational cohort study included patients undergoing short stem THA with the optimys prosthesis. Follow-up examinations were performed at specific intervals up to 7 years postoperatively. Operation characteristics, general and specific complications, revisions, VAS rest pain, VAS load pain, VAS patient satisfaction, and Harris Hip Score (HHS) were recorded and statistically compared between obese (BMI ≥ 30 kg/m2) and non-obese (BMI < 30 kg/m2) patients.

RESULTS

Of the 224 patients included with a mean follow-up of 87.2 months (range 81.9-104.0), 69 were assigned to the OB group and 155 to the non-OB group. A minimally invasive approach was significantly less often selected in obese patients (p = 0.049), whereas operating time and length of hospital stay were not significantly different. The rate of general and specific complications did not significantly differ between both groups. Survival of the optimys prosthesis was 99.1% at 7-year follow-up and one patient per group had to undergo revision surgery. VAS rest pain, load pain, and satisfaction improved from preoperatively to postoperatively in both groups without a significant difference between both groups. While the HHS was improved from preoperatively to postoperatively, obese patients showed a significantly lower HHS at the 7-year follow-up (p = 0.01) but still exhibited an excellent scoring above the PASS threshold.

CONCLUSION

Short stem THA with the optimys prosthesis is a safe and effective option also in obese patients with an excellent clinical outcome and a low complication rate.

A neck-sparing short stem shows significantly lower blood loss in total hip arthroplasty compared to a neck-resecting short stem

Short stems are associated with a significantly lower blood loss (BL) compared to straight stems in total hip arthroplasty (THA). Different types of stems differ in design, fixation and level of femoral neck osteotomy. Therefore, we sought to evaluate the difference regarding the perioperative BL between two short stems with different designs in direct anterior approach (DAA). A total of 187 THA performed by a single surgeon were analysed. 107 patients received a neck-resecting (Group A) and 80 patients a neck-sparing short stem (Group B). Blood counts of the day before surgery and of two days after surgery were evaluated. Total blood volume and BL were calculated. Additionally, duration of surgery was analysed. The perioperative BL was significantly lower in Group B (451.4 ± 188.4 ml) compared to Group A (546.6 ± 232.7 ml; p = 0.002). The postoperative haematocrit (31.6 ± 3.7% vs. 30.4 ± 4.4%; p = 0.049) and haemoglobin-level (11.0 ± 1.3 g/dL vs. 10.4 ± 1.5 g/dL; p = 0.002) were significantly higher in Group B. Duration of surgery was significantly shorter in Group B (62.0 ± 11.4 min vs. 72.6 ± 21.8 min; p < 0.001). The use of a neck-sparing short stem leads to a significantly decreased BL compared to a neck-resecting short stem in DAA THA. A less extensively conducted capsular release necessary for optimal femoral exposition might lead to a lower perioperative BL and shorter durations of surgery.

Low Risk of Fracture Using a Cementless Triple-tapered Collared Femoral Stem with Automated Impaction in Direct Anterior Approach Total Hip Arthroplasty

INTRODUCTION

Direct anterior approach (DAA) total hip arthroplasty (THA) has been associated with increased periprosthetic femoral fracture (PFF) risk. The aim of our study was to evaluate the fracture risk utilizing a triple tapered, collared stem with automated impaction through the anterior approach.

METHODS

We retrospectively reviewed consecutive DAA THA procedures at a single institution performed by four experienced DAA THA surgeons between 2019 and 2021. We collected data on age, sex, body mass index, preoperative diagnosis, and intraoperative and early postoperative PFF within 6 weeks postoperatively. Preoperative radiographs were evaluated to determine femoral neck-shaft angle and Dorr classification. We used Wilcoxon Rank sum or Chi-square tests to assess differences between patients who did and did not have PFF. We also evaluated potential risk factors for PFF in unadjusted and adjusted regression analyses. In all, 24 PFFs (1.6%) occurred. There were eighteen fractures (1.2%) recognized and managed intraoperatively (15 calcar, 2 greater trochanter, 1 posterior cortical). There were six PFFs (0.4%) identified postoperatively (5 greater trochanter, 1 diaphyseal), of which 1 required a revision surgery.

RESULTS

Identified risk factors for fracture in adjusted regression models included women (Odds Ratio (OR)=2.76, P=0.047), preoperative coxa valga (OR= 4.54, P=0.005), and coxa vara (OR=2.85, P=0.03).

CONCLUSION

The incidence of periprosthetic femoral fractures is low using a triple tapered, collared cementless femoral stem with automated impaction through the DAA. Our findings agree with previous reports that have demonstrated women and preoperative valgus neck angle are risk factors for PFF.

Is the Direct Anterior Approach for Total Hip Arthroplasty Effective in Obese Patients? Early Clinical and Radiographic Results from a Retrospective Comparative Study

Background and objectives: Total hip arthroplasty (THA) in obese patients (BMI > 30) is considered technically demanding, and it is associated with higher rates of general and specific complications including infections, component malpositioning, dislocation, and periprosthetic fractures. Classically, the Direct Anterior Approach (DAA) has been considered less suitable for performing THA surgery in the obese patient, but recent evidence produced by high-volume DAA THA surgeons suggests that DAA is suitable and effective in obese patients. At the authors' institution, DAA is currently the preferred approach for primary and revision THA surgery, accounting for over 90% of hip surgeries without specific patient selection. Therefore, the aim of the current study is to evaluate any difference in early clinical outcomes, perioperative complications, and implant positioning after primary THAs performed via DAA in patients who were divided according to BMI. Material and methods: This study is a retrospective review of 293 THA implants in 277 patients that were performed via DAA from 1 January 2016 to 20 May 2020. Patients were further divided according to BMI: 96 patients were normal weight (NW), 115 were overweight (OW), and 82 were obese (OB). All the procedures were performed by three expert surgeons. The mean follow-up was 6 months. Patients' data, American Society of Anesthesiologists (ASA) score, surgical time, days in rehab unit, pain at the second post-operative day recorded by using a Numerical Rating Scale (NRS), and number of blood transfusions were recorded from clinical charts and compared. Radiological evaluation of cup inclination and stem alignment was conducted on post-operative radiographs; intra- and post-operative complications at latest follow-up were recorded. Results: The average age at surgery of OB patients was significantly lower compared to NW and OW patients. The ASA score was significantly higher in OB patients compared to NW patients. Surgical time was slightly but significantly higher in OB patients (85 ± 21 min) compared to NW (79 ± 20 min, p = 0.05) and OW patients (79 ± 20 min, p = 0.029). Rehab unit discharge occurred significantly later for OB patients, averaging 8 ± 2 days compared to NW patients (7 ± 2 days, p = 0.012) and OW patients (7 ± 2 days; p = 0.032). No differences in the rate of early infections, number of blood transfusions, NRS pain at the second post-operative day, and day of post-operative stair climbing were found among the three groups. Acetabular cup inclination and stem alignment were similar among the three groups. The perioperative complication rate was 2.3%; that is, perioperative complication occurred in 7 out of 293 patients, with a significantly higher incidence of surgical revisions required in obese patients compared to the others. In fact, OB patients showed a higher revision rate (4.87%) compared to other groups, with 1.04% for NW and 0% for OW (p = 0.028, Chi-square test). Causes for revision in obese patients were aseptic loosening (2), dislocation (1), and clinically significant post-operative leg length discrepancy (1), with a revision rate of 4/82 (4.87%) during follow-up. Conclusions: THA performed via DAA in obese patients could be a solid choice of treatment, given the relatively low rate of complications and the satisfying clinical outcomes. However, surgical expertise on DAA and adequate instrumentation for this approach are required to optimise the outcomes.

Direct anterior approach hip arthroplasty: How to reduce complications - A 10-years single center experience and literature review

BACKGROUND

The direct anterior approach for total hip arthroplasty (DAA-THA) is increasing in popularity due to some advantages such as less surgical trauma, minimal dissection of soft tissues, shorter rehabilitation times, faster return to daily activities, lower incidence of dislocation. On the other hand, the literature reports a high rate of intraoperative complications, with many different rates and complication types in the published papers.

AIM

To analyze our complications comparing results with the literature; to report measures that we have taken to reduce complications rate.

METHODS

All DAA-THA patients with one year minimum follow up who were operated at a single high-volume centre, between January 2010 and December 2019 were included in this retrospective study. All surgeries were performed using cementless short anatomical or straight stems and press fit cups. Patients’ follow-up was performed, at 6 wk, 3 mo, then annually post-surgery with clinical and radiological evaluation. Primary outcomes were stem revision for aseptic loosening and all-cause stem revision. Second outcome was intra-operative and post-operative complications identification.

RESULTS

A total of 394 patients underwent DDA-THA from January 2010 and December 2019, for a total of 412 hips; twelve patients lost to follow-up and one patient who died from causes not related to surgery were excluded from the study. The average age at the time of surgery was 61 years (range from 28 to 78 years). Mean follow-up time was 64.8 mo (range 12-120 mo). Seven stems were revised. One cortical perforation, one trochanteric and lateral cortical wall intraoperative fracture, one diaphyseal fracture, three clinically symptomatic early subsidence and one late aseptic loosening. We also observed 3 periprosthetic fractures B1 according to the Vancouver Classification. Other minor complications not requiring stem revision were 5 un-displaced fractures of the calcar region treated with preventive cerclage, one early infection, one case of late posterior dislocation, 18 case of asymptomatic stem subsidence, 6 cases of lateral cutaneous femoral nerve dysesthesia.

CONCLUSION

DAA is associated to good outcomes and lower incidence of dislocation. Complication rate can be reduced by mindful patient selection, thorough preoperative planning, sufficient learning curve and use of intraoperative imaging.