What Factors Predict Improvements in Outcomes Scores and Reoperations After the Bernese Periacetabular Osteotomy?

Abstract

Background The Bernese periacetabular osteotomy (PAO) has entered its fourth decade and is frequently used for corrective osteotomy in patients with acetabular dysplasia. Although our capacity to preserve the joint after corrective osteotomy is excellent, gaining a better understanding on how well patients function after this surgery is important as well. Questions/purposes (1) What changes in patient-reported outcomes scores occur in patients treated with PAO for hip dysplasia in the setting of a single-surgeon practice? (2) What are the predictors of clinical function and survivorship? Methods All 67 patients presenting to a single surgeon's clinic with hip dysplasia treated with PAO between October 2005 and January 2013 were prospectively followed. Baseline demographic data as well as pre-and postoperative radiographic and functional measurements were obtained with a minimum of 1-year followup. Radiographic criteria included Tönnis grade, Tönnis angle, minimum joint space width, center-edge angle, presence of crossover sign, medial translation of the hip center, and alpha angle. We also used validated outcome measures including the WOMAC, the UCLA Activity Scale, and the SF-12. Multiple regression analysis was used to determine predictors of functional outcome scores. Results There were increases in WOMAC, UCLA, and SF-12 Physical scores. Higher preoperative alpha angle was associated with a lower postoperative WOMAC score (b = À0.47; 95% confidence interval [CI], À0.92 to À0.02; R 2 = 0.08; p = 0.04). The 5-year Kaplan-Meier survivorship was 94.1% (95% CI, 90.7-97.5) with reoperation (ie, hip arthroscopy and/or total hip arthroplasty) used as the endpoint for failure. With the limited numbers available, we could not identify any demographic or radiographic factors associated with reoperation. Conclusions Overall survivorship for the PAO at our center at 5 years is comparable to other clinical series with overall functional scores improving. A greater alpha angle preoperatively was associated with poorer patient-reported outcome scores. Further research is needed to determine how and when intraarticular cartilage damage associated with dysplasia needs to be addressed. Level of Evidence Level IV, therapeutic study.

Survivorship of the Bernese Periacetabular Osteotomy: What Factors are Associated with Long-term Failure?

“…In our study, the mean long-term postoperative UCLA Activity Score was 7 ± 2 for the asymptomatic hips and 6 ± 2 for symptomatic hips. These results are comparable to Beaulé et al's [5] and van Bergayk and Garbuz' [44]. We are able to show at long-term followup that patients undergoing PAO whether asymptomatic or symptomatic are able to remain regularly active.…”

“…Few studies have reported on activity-related and quality-of-life outcomes after PAO. Beaulé et al [5] in their 2014 series on dysplastic hips reported a preoperative UCLA score of 5.3 with an improvement to 6.6 at a median of 5 years postoperative followup. van Bergayk and Garbuz [44] reported on quality of life and sports-specific outcome measures on a small cohort of 22 patients with followup of 2 years.…”

“…DDH is a known cause of pain and is a substantial cause of morbidity in the young adult population [2,5,17]. Few studies have reported on activity-related and quality-of-life outcomes after PAO.…”

“…With conversion to THA or WOMAC pain score C 10 as the endpoint, 76% of hips survived at an average of 9 years. As the PAO is becoming more widely used [5,8,26,28,30], knowledge of longterm outcomes is necessary to educate providers and stratify patients who will benefit from surgery. Predictors of failure and poor outcomes have been linked to advanced age, advanced preoperative arthrosis, flawed preoperative joint congruency, larger preoperative alpha angles, and postoperative impingement [2,31,40,43].…”

Hip Dysplasia in the Young Adult

“…The risk of total hip arthroplasty at five years after periacetabular osteotomy was 12% in hips with a preoperative Tönnis grade of 0 or 1 and 27% in hips with a Tönnis grade of 2. In a more recent study of the predictors of clinical outcome after periacetabular osteotomy, Beaulé et al 94 found that a higher preoperative alpha angle was significantly associated with a lower functional score postoperatively, potentially indicating more severe articular damage persisting after surgical correction. Anteroposterior pelvic radiograph after a periacetabular osteotomy was done on the right hip with correction of acetabular retroversion.…”