Borderline Hip Dysplasia and Secondary Femoroacetabular Impingement Surgery – Rehabilitation Principles and Rationale

BACKGROUND: Hip arthroscopy has grown in recent decades, especially surrounding conditions such as borderline hip dysplasia. Traditionally, frank dysplasia is addressed with open periacetabular osteotomy. Recently, the concept of borderline dysplasia resulting in instability has gained acceptance as a distinct pathology. Patients with borderline dysplasia may experience symptoms of femoroacetabular impingement or instability either in isolation or combination. CLINICAL QUESTION: What are the unique considerations of borderline hip dysplasia in this context and how can postoperative rehabilitation programs be tailored to achieve optimal outcomes in patients undergoing hip arthroscopic surgery? KEY RESULTS: We provide an overview of the condition and its diagnostic challenges and propose a 5-phase postoperative rehabilitation protocol consisting of (1) anterior soft tissue protection phase with restricted range of motion and protected partial weight-bearing; (2) restoration of uniplanar hip mobility and neuromuscular control while minimizing iliopsoas irritation; (3) restoration of full hip mobility and strengthening of the global hip musculature, along with reintroduction of functional exercises and instrumental activities of daily living; (4) functional training tailored to the patient’s specific occupational and/or recreational demands; and (5) normalization of muscle strength and progressive return-to-sport and recreational activities with a conservative-paced approach. CLINICAL APPLICATION: Rehabilitation for people having hip arthroscopy to treat borderline hip dysplasia must (1) focus on protecting the anterior soft tissues, and safeguarding and gradually strengthening the iliopsoas and pectineus tendons to enhance stability, (2) reduce emphasis on posteriorly rotating the pelvis, and (3) take a cautious approach to return to sport. JOSPT Open 2025;3(3):246-253. Epub 17 March 2025. doi:10.2519/josptopen.2025.0088