Total Hip Arthroplasty With Trochanteric Ostectomy for Patients With Angular Deformity of the Proximal Femur

Total Hip Arthroplasty with Extra-small Femoral Stems in Extremely Hypoplastic Femurs: A Case-Series Study

Background

Total hip arthroplasty (THA) in patients with hypoplastic femurs presents a significant challenge to orthopedic surgeons due to the limited space available for implant placement. Therefore, the extra-small femoral stems have been proposed as a solution to this problem, but there are limited data on the outcomes. We aimed to evaluate clinical and radiological outcomes of THA in patients with extremely hypoplastic femurs using the Bencox CM stem (Corentec), an extra-small femoral stem.

Methods

We included 6 hips from 4 patients. The mean age of the patients was 41.2 years (range, 19.6-60.4 years). The mean height was 135.1 cm (range, 113.6-150.0 cm) with a mean body mass index of 25.7 kg/m2 (range, 21.3-31.1 kg/m2). The diagnoses for THA were sequelae of septic arthritis in childhood, pseudoachondroplasia, spondyloepiphyseal dysplasia, and juvenile rheumatoid arthritis. Preoperative computed tomography scans were conducted to assess the extent of proximal femoral hypoplasia. The clinical outcomes were assessed using the modified Harris Hip Score, while the radiological outcomes were evaluated using radiographs. The mean follow-up was 2.3 years (range, 1.0-5.9 years).

Results

The average modified Harris Hip Score improved to 88.8 at the final follow-up. Intraoperative femoral fractures occurred in 2 cases (33.3%). During the follow-up, 1 stem underwent varus tilting from postoperative 6 weeks to 6 months without subsidence. Otherwise, all stems showed good osteointegration at the latest follow-up. No hip dislocations, periprosthetic joint infection, or loosening of the prosthesis occurred.

Conclusions

The use of extra-small femoral stems in THA for extremely hypoplastic femurs can provide reasonable clinical and radiological outcomes with minimal complications. We suggest that this femoral stem could be a viable option for patients with extremely hypoplastic femurs.

I s pelvic support osteotomy (PSO) suitable for ordinary high-riding hip dysplasia?

PURPOSE

Pelvic support osteotomy (PSO) is regarded to provide pelvic stability and improve abductor function to delay or even avoid total hip arthroplasty (THA) in young patients with high-riding hip dysplasia. However, some of these patients eventually have to undergo THA. Because of the double-angulation deformity of the femur after PSO, subsequent THA is challenging. This study aimed to analyze whether PSO surgery is suitable for high-riding hip dysplasia and summarize orthopaedic strategy during THA for patients with previous PSO.

METHODS

This case-control study included eight cases of THA for high-riding hip dysplasia patients with previous PSO (study group) and 24 cases of high-riding hip dysplasia patients without any hip surgical therapy (control group) by a 1:3 match (from May 2018 to January 2022). We compared demographics and joint function before and after THA between two groups and recorded all patients' preoperative imaging data, surgical procedures, postoperative imaging data, and complications. The surgical techniques for patients with previous PSO were highlighted.

RESULTS

There was no statistical difference between the two groups in demographic (p > 0.05). The study group had worse hip Harris score (HHS), range of motion (ROM), visual analogue scale (VAS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) (p < 0.05) compared with the control group before THA. All patients had concurrent THA and osteotomy at the proximal femur, but the study group experienced longer operation time (p = 0.047) with more blood loss (p = 0.027) and higher complication rate compared with the control group (p = 0.009). At the last follow-up, the study group's HHS, ROM, VAS, and WOMAC were still worse than those in the control group.

CONCLUSIONS

PSO did not improve the joint function of high-riding hip dysplasia patients but brought challenges to subsequent THA and affected the surgical outcomes. In short, we suggested that PSO is unsuitable for routine high-riding hip dysplasia patients.

Treatment of Osteoarthritis Secondary to Severe Coxa Vara with Modular Total Hip Arthroplasty

Objective

We aimed to demonstrate the methods of treatment for coxa vara with modular total hip arthroplasty (THA) and evaluate clinical and radiographic outcomes, and further survivorship at the midterm follow-up.

Methods

We retrospectively reviewed 33 patients (42 hips) who underwent modular THA for coxa vara deformity from May 2008 to December 2019. The clinical and radiographic results, including Harris Hip Score (HHS), leg length discrepancy (LLD), greater trochanteric height, femoral offset, abductor lever arm, stem alignment and limp, and complications, were evaluated.

Results

The follow-up time was mean 69.9±43.7 months. Clinically, the HHS improved significantly (p<0.001) on average from 42.90±14.44 points to 89.54±4.75 points. The mean LLD decreased from 33.3±19.4 mm to 5.0±5.8 mm (p<0.001), and 27 patients (82%) thought that total equality of the lower limbs was obtained. Patients demonstrated diminished or no limping in 88% (29/33) of hips and a significant improvement of biomechanics. At the final follow-up, all stems of hips were in clinical neutral alignment and the prostheses survivorship rates for all-causes revisions was 97.6%.

Conclusion

Modular THA is a valuable alternative to render favorable outcomes for treatment of osteoarthritis secondary to severe coxa vara.

Locking compression plate fixation of femoral intertrochanteric fractures in patients with preexisting proximal femoral deformity: a retrospective study

Background

To investigate the clinical efficacy of locking compression plate fixation for the treatment of femoral intertrochanteric fractures in patients with preexisting proximal femoral deformity.

Methods

A retrospective analysis was conducted on 37 patients with femoral intertrochanteric fractures combined with preexisting proximal femoral deformity between January 2013 and July 2019. The patients included 24 males and 13 females aged from 23 to 69 years old, with an average age of 47.5 years. The preexisting proximal femoral deformities resulted from poliomyelitis sequela, proximal femoral fibrous dysplasia, malunion and implant failure combined with coxa vara after intramedullary nailing fixation. There were 6 cases of 31-A2.1, 6 cases of 31-A2.2, 20 cases of 31-A3.1, and 5 cases of 31-A3.2, determined based on the AO classification of intertrochanteric fractures. All fractures were managed through open reduction and locking plate fixation. The hip disability and osteoarthritis outcome score (HOOS) was used to assess hip function before injury and at the last postoperative follow-up. The short form 36 (SF-36) Health Survey Questionnaire was used to assess quality of life.

Results

Thirty-seven patients were followed up for 12 to 27 months (average, 20.7 months). All patients achieved bone healing within 5.1 months on average (range, 3 to 6 months). Postoperative complications included deep vein thrombosis in three patients, bedsores in one and delayed union in one patient. No other complications, such as surgical site infection, fat embolism, nonunion and re-fracture, were presented. There was no significant difference in the HOOS scores and the SF-36 Health Questionnaire outcomes at pre-injury and at the last postoperative follow-up (p > 0.05).

Conclusions

It is difficult to perform intramedullary fixation of femoral intertrochanteric fractures in patients with preexisting proximal femoral deformity, while locking compression plate fixation is a simple and effective method of treatment.