Periacetabular osteotomy: A novel application of modified Stoppa approach

Functional and radiological outcomes and complications of bernese periacetabular osteotomy through modified Stoppa approach

BACKGROUND

The Smith-Peterson approach and its modifications provide an extensive exposure and allow osteotomies through a single incision. However, the risk of complications increases when the quadrilateral surface, ischial and pubic osteotomy sites cannot be seen. This study aimed to evaluate the surgical characteristics, complications, and functional and radiological outcomes of patients with acetabular dysplasia who underwent Bernese periacetabular osteotomy (PAO) through modified Stoppa approach and plate-screw fixation.

METHODS

The study included 31 patients (41 hips) who had undergone PAO using a modified Stoppa approach. The characteristics of patients and the surgical procedure were described. The lateral centre-edge angle (LCEA) and Tönnis roof angle were evaluated in the radiological outcome evaluation. The modified Harris Hip Score (mHHS) was used to evaluate functional outcome. Furthermore, complications were described.

RESULTS

The mean age of the patients was 20.4 ± 9.0 years. Of the 31 patients, 21 underwent unilateral Bernese PAO and 10 underwent bilateral Bernese PAO. The mean follow-up period was 25.1 ± 8.8 months. Postoperatively, the mean mHHS improved significantly (68.8 ± 9.4 vs. 88.8 ± 10.0, p < 0.001). Postoperatively, the mean LCEA and Tönnis roof angle improved significantly (17.7 ± 6.0 vs. 42.2 ± 4.8, p < 0.001 for LCEA and 18.3 ± 5.5 vs. 8.0 ± 2.2, p < 0.001 for Tönnis roof angle). There was no significant correlation between preoperative to postoperative improvement in LCEA or Tönnis roof angle and improvement and mHHS (p > 0.005). 5 complications were identified: 1 transient sciatic nerve palsy, 1 external iliac vein injury, 1 infection, and 2 screw irritations of acetabulum.

CONCLUSIONS

Performing Bernese PAO through a modified Stoppa approach with plate-screw fixation results in acceptable complication rates, immediate early weight-bearing opportunity, and improved functional and radiological outcomes in patients with acetabular dysplasia.

Incidence and clinical outcome of lateral femoral cutaneous nerve injury after periacetabular osteotomy

Aims

Lateral femoral cutaneous nerve (LFCN) injury is a complication after periacetabular osteo-tomy (PAO) using an anterior approach, which might adversely affect the outcome. However, no prospective study has assessed the incidence and severity of this injury and its effect on the clinical outcomes over a period of time for longer than one year after PAO. The aim of this study was to assess the incidence and severity of the symptoms of LFCN injury for ≥ three years after PAO and report its effect on clinical outcomes.

Methods

A total of 40 hips in 40 consecutive patients who underwent PAO between May 2016 and July 2018 were included in the study, as further follow-up of the same patients from a previous study. We prospectively evaluated the incidence, severity, and area of symptoms following LFCN injury. We also recorded the clinical scores at one year and ≥ three years postoperatively using the 36-Item Short Form Health Survey (SF-36) and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) scores.

Results

A total of 20 patients (50%) had symptoms of a LFCN injury at one year after PAO. At ≥ three years postoperatively, the symptoms had completely resolved in seven of these patients and 13 (33%) had persistent symptoms. The severity and area of symptoms did not significantly differ between one and ≥ three years postoperatively. The JHEQ showed significant differences in the patient satisfaction and mental scores between those with and those without sypmtoms of LFCN injury at ≥ three years postoperatively, while there was no significant difference in the mean SF-36 scores.

Conclusion

The incidence of LFCN injury after PAO using an anterior approach is high. The outcome of PAO, ≥ three years postoperatively, is poorer in patients with persistent symptoms from a perioperative LFCN injury, in that patient satisfaction and mental health scores are adversely affected.

Making the cut: a technical note and literature review of Bernese periacetabular osteotomy techniques with special attention to ischial osteotomy initiation and completion with an inside to anterior curved osteotomy

Periacetabular osteotomy includes a fluoroscopy-guided ischial cut without direct visualization. Previously described techniques include a mediolateral ischial cortex cut, which is associated with the risk of injuring nearby nerves. Another drawback of that technique is the difficulty connecting an ischial cortex cut with a retroacetabular cut due to orthogonal nature of the osteotomy. In general, an additional cut from medial to lateral is required. The present study aimed to describe a technique that eliminates those problems due to use of only a central cut of the ischium and the curved nature of the osteotomy.

A bibliometric analysis and visualization of research trends on periacetabular osteotomy

Bernese periacetabular osteotomy (PAO) is a practical and safe acetabular reorientation technique used to correct structural hip deformities, and much relevant literature has been published over the past decades. This bibliometric study aims to determine the status of PAO research between 1994 and 2022. Information about PAO research publications from 1994 to 2022 was obtained from the Web of Science Core Collection. This bibliometric study is implemented and analyzed through three bibliometric tools with respect to publication counts, countries, institutions, authors, journals, funding agencies, references and keywords. In total, 634 publications concerning PAO were identified. The United States and Washington University in St. Louis have published the most literature in terms of country and institution. Additionally, Switzerland and the University of Bern are the country and the institution with the highest average number of citations in the PAO field. The most published and co-cited journal is Clinical Orthopaedics and Related Research. Burst keyword detection has discovered that 'patient-reported outcome', 'instability', 'risk', 'survivorship' and 'outcome' are regarded as the current research frontier. In summary, our findings provide insight into the bibliometric overview of research status in the PAO field, which may offer later investigators' references in exploring further research directions.