Prevalence Of Cam-Type Femoroacetabular Impingement Among Total Hip Arthroplasty Patients and Its Association with Hip Osteoarthritis: An 11-Year Cross-Sectional Analytical Study In The Philippines (Single Institution Study)

Introduction: Cam-type Femoroacetabular Impingement (FAI) relates to a non-spherical osseous prominence of the proximal femoral neck or head-neck junction. This bony morphologic abnormality of the hip joint may result in abnormal contact during motion and can result in impingement and abrasion of the femoral head-neck junction on the acetabular rim, hence as theorized in multiple studies, a mechanical relation between FAI and the development of osteoarthritis (OA) of the hip is possible. The prevalence rate of Cam-type FAI also varies on anatomic orphology in different population-based studies.

Objectives: The purpose of this study is:

To determine the prevalence of Cam-type Femoroacetabular Impingement Among Total Hip Arthroplasty Patients in Filipino patients

To determine the association between Femoroacetabular Impingement and Hip Osteoarthritis among total hip arthroplasty Filipino patients

Methods: Using a cross-sectional analytical study, we retrospectively investigated patients with the following inclusion criteria: 1. Filipino patient who underwent Total Hip Arthroplasty in Makati Medical Center (MMC) from January 2011 to March 2022. 2. With Radiograph (Pelvis AP) done in our institution using the NovaPacs viewer database. The following were the exclusion criteria: Patients with a diagnosis of hip dysplasia, inflammatory arthritis, osteonecrosis of the femoral head, previous hip surgery, and post-traumatic arthritis. Preoperative plain anteroposterior (AP) pelvis radiographs were used and α-angle of 55 degrees and more was measured to determine the presence of a cam lesion.

Results: Radiological Cam-type FAI prevalence among Filipino populations who underwent Total Hip Arthroplasty was found in 27% of the population. Our results showed that among 270 patients (293 hips) who underwent total hip arthroplasty in Makati Medical Center from January 2011- March 2022, a total of 123 patients were diagnosed with primary osteoarthritis. Of these 123 patients (128 hips), 56% had a cam lesion, 69 patients (71 hips) had a cam lesion, and 56 patients (57 hips) did not have a cam lesion. Patients found to have cam lesions were also more common in male patients younger than 60 years old.

Conclusion: Patients with primary osteoarthritis may also be due to Cam-type Femoroacetabular Impingement among Filipino patients. Our study shows that Cam-type FAI suggests an association with advanced primary osteoarthritis among the Filipino population.