What Is the Early/Mid-term Survivorship and Functional Outcome After Bernese Periacetabular Osteotomy in a Pediatric Surgeon Practice?

Abstract

Background The Bernese periacetabular osteotomy (PAO) is a recognized joint-preserving procedure. Achieving joint stability without creating impingement is important, but the orientation target that best balances these sometimes competing goals has not yet been clearly defined. Moreover, the learning curve of this challenging procedure has not been described. Questions/purposes The purposes of this study were (1) to determine the 10-year survivorship and functional outcome after Bernese PAO in a single-surgeon series; (2) to review which patient, surgical, and radiographic factors might predict outcome after the procedure; and (3) to define the learning curve for target acetabular correction. Methods The first 68 PAOs performed for symptomatic hip dysplasia were retrospectively evaluated. None have been lost to followup with followup less than 2 years. Endpoints for the lost to followup (n = 2) are at the time of when last seen. During the study period, the same surgeon performed 562 pelvic osteotomies (including Salter, Pemberton, Dega and Chiari) and 64 shelf acetabuloplasties. Bernese PAO was used only for symptomatic dysplasia (center-edge angle\25°and nonhorizontal acetabular roof) in developmentally mature hips without evidence of major joint incongruence or subluxation. Most patients were female (n = 49 [60 hips, 88%]); mean age at operation was 25 years (SD 7). Sixteen hips had previous hip procedures. The study's mean followup was 8 years (range, 2-18 years). Patient-reported functional outcome was obtained using the WOMAC score (best-worst: 0-96). Radiographic parameters of dysplasia (acetabular index [AI], center-edge angle [CEA], congruency, Tönnis grade, and joint space) were evaluated from preoperative and postoperative radiographs using computer software. Results The 10-year survival rate was 93% (95% confidence interval [CI], 82%-100%); four patients underwent further surgery to the hip in the study period. The mean WOMAC was 12 (range, 0-54 Conclusions This study reports excellent results after Bernese PAO in the hands of an experienced pediatric hip surgeon. We advocate cautious correction of the acetabular fragment. Future studies should concentrate on how to determine what the optimal target is and how to achieve it intraoperatively, minimizing the learning curve associated with it. Level of Evidence Level III, therapeutic study.

One-third of Hips After Periacetabular Osteotomy Survive 30 Years With Good Clinical Results, No Progression of Arthritis, or Conversion to THA

“…The increased survivorship could be the result of the decreased age at operation [2,3,12,33,57], typically in hips with Chiari or triple osteotomies [2,12,19]. Other possible reasons include the lack of hips with advanced osteoarthritis [14,44,54], a lower followup rate [7,11,23,25,31,32,35,45,53], and a decreased percentage of hips with previous surgery [28,54]. In addition, the current patient series is consecutive and includes the very first cases from a new surgical technique and therefore represent the beginning of the learning curve.…”

“…Next, various factors associated with failure that are subject to surgical accuracy are reported (Table 6). These include a postoperative deficient acetabular coverage [1,7,11,14,23,41] as a result of undercorrection or postoperative joint incongruency [11,14,28,57]. In addition, excessive acetabular coverage [11,14], acetabular retroversion [1], or nonspherical femoral head [1,33,56] were reported, which potentially can result in postoperative femoroacetabular impingement.…”

Developmental Dysplasia of the Hip

“…Several studies revealed that 93% to 95% of young patients undergoing PAO (mean age: 25.4-26 years) did not require a hip replacement at 10 years' follow-up. 55,56 There is a paucity of long-term follow-up of PAO. The only long-term study of >30 years' follow-up revealed that as many as 71% of patients continued to progress to develop pain symptoms, have radiographic evidence of osteoarthritis, or require hip replacement after PAO.…”

Structured-mentorship Program for Periacetabular Osteotomy Resulted in Few Complications for a Low-volume Pelvic Surgeon

“…Their overall survivorship at 12.4 years was 75% (95% CI, 68%-80%) after the exclusion of 50 hips resulting from loss to followup [20]. Other highvolume studies have reported a survivorship range between 75% and 93% over 10 years with varying numbers lost to followup [15,18,20,29,40,44]. Survivorship at 12 years in the current study group was 94% (95% CI, 85%-98%).…”