The incidence and risk factors for stress fracture following periacetabular osteotomy

Abstract

Aims The aims of this study were to characterize the incidence and risk factors associated with stress fractures following periacetabular osteotomy, and to determine their effect on osteotomy union. Methods We retrospectively reviewed all periacetabular osteotomies (PAOs) performed for developmental dysplasia of the hip (DDH) at one institution over a six-year period between 2012 and 2017. Perioperative factors were recorded, and included demographic and surgical data. Postoperatively, patients were followed for a minimum of one year with anteroposterior and false profile radiographs of the pelvis to monitor for evidence of stress fracture and union of osteotomies. We characterized the incidence and locations of stress fractures, and used univariate and multivariable analysis to identify factors predictive of stress fracture and the association of stress fracture on osteotomy union. Results A total of 331 patients underwent PAO during the study period with 56 (15.4%) stress fractures: 46 fractures of the retroacetabular posterior column, five cases of ischiopubic stress fracture, and five cases of concurrent ischiopubic and retroacetabular stress fractures. Overall, 86% (48/56) healed without intervention. Univariate analysis revealed that stress fractures occurred more frequently in females (p = 0.040), older patients (mean age 27.6 years (SD 8.4) vs 23.8 (SD 9.0); p = 0.003), and most often with the use of the broad Mast chisel (28.5%; p < 0.001). Multivariable analysis revealed that increasing age (odds ratio (OR) 1.04; 95% CI 1.01 to 1.07; p = 0.028) and use of the broad Mast chisel (OR 5.1 (95% CI 1.3 to 19.0) compared to narrow Ganz chisel; p = 0.038) and surgeon (p = 0.043) were associated with increased risk of stress fracture. Patients with stress fractures were less likely to have healed osteotomies after one-year follow-up (76% vs 96%; p < 0.001). Conclusion Stress fracture of the posterior column may be an under-recognized complication following PAO, and the rate may be influenced by surgical technique. Consideration should be given to using a narrow chisel during the ischial cut to reduce the risk of stress propagation through the posterior column. Cite this article: Bone Joint J 2022;104-B(9):1017–1024.

Factors influencing patient-reported outcomes following periacetabular osteotomy and open osteochondroplasty in the setting of borderline hip dysplasia

“…61 It ranges from psychosocial burden from long rehabilitation to under-recognized debilitating stress fractures. 62 Unlike HA, which has an overall complication rate of 3% in a systematic review including 26,000 cases, PAO has been associated with a 7% complication rate, mostly due to wound problems and higher rates of nerve injuries. 63-65 In our cohort, 33% of hips had changes in the LFCN dermatome, but these did not influence the PROMs and were only reported when questioned or examined.…”

Important matters that need attention

“…However, there are still very significant question marks over how and when periacetabular osteotomy should be performed, and what adjunctive treatments are needed. [21][22][23][24][25][26][27][28][29] A great deal more research is needed.…”

Psychological status affects postoperative quality of life, function, and pain after periacetabular osteotomy

“… 2 If diagnosed in time, PAO is the surgical therapy of choice with the goal of preserving the native hip joint, relief of pain and maintenance of activity. 3 It was previously shown that both joint-specific function and quality of life improve after PAO. 4 …”

“…2 If diagnosed in time, PAO is the surgical therapy of choice with the goal of preserving the native hip joint, relief of pain and maintenance of activity. 3 It was previously shown that both joint-specific function and quality of life improve after PAO. 4 Age at the time of surgery, preoperative degree of osteoarthritis (OA), and preoperative joint-specific function are critical criteria to consider in the indication as they affect outcome.…”