Because FAI is a dynamic cause of hip arthritis, it is imperative to correctly diagnose and treat FAI. Chronic clinical symptoms, FAI attributes from X-ray images, and damage to the labrum and cartilage of the joint are all indicators for operative therapy to resolve FAI . A patient with cam/pincer type FAI who came to our clinic was previously treated with arthroscopic surgery and received limited relief from the operation. When the patient was seen in our clinic, they had progressed to arthritis, and a total hip replacement was required. This example highlights the importance of correct diagnosis and treatment. For the treatment of purely pincer FAI with total or global retroverted acetabulum, we choose to do primary reverse pelvic osteotomy, because it’s one of the only method to change the orientation of the acetabulum (Figure 8B).
Beaulé et al  found that an alpha angle in FAI cam type, of more than 65° was a risk factor for cartilage damage inside the hip joint and was associated with delamination of the cartilage with or without tears resulting in macroscopic classification of degree 3 according to Beck et al . However, there is no correlation between the cross-over sign and damage to the cartilage. Anderson et al  and Johnston et al  specified that the alpha angle was also a risk factor for delamination of the cartilage of the acetabulum and could quantify cam type FAI deformity. Barton et al  observed that the alpha angle has a 70%-90 % reliability on the planar X-rays when diagnosing FAI. An X-ray positive finding of FAI that is actually clinically negative is found in 14% of patients. But a perioperative finding of acetabulum cartilage destruction is found in 44%-75% of patients. Computed tomography and magnetic resonance imaging scans have advantages in diagnosing FAI with 3D reconstruction. They reveal the deformity of the femoral head, acetabulum, and cervicocapital junction of the hip joint particularly well. However, it is not always practical to obtain computed tomography and magnetic resonance images. Therefore, it is important to correctly interpret the X-ray images.
Siebenrock et al  reported a series of patients who received periacetabular osteotomy for reorientation of the retroversion of the acetabulum and observed that 90% of patients had great results. We followed this results, and we perfomed the osteotomies to correct the FAI before we choose to do total hip replacement. To prevent the intraarticular affection we didn’t use the surgical hip dislocation as an intraarticular procedure.
It is necessary to do this osteotomy in the correct position (i.e. to the inner rotation and flexion) because this type of osteotomy can cause secondary rear FAI. The iliofemoral approach is recommended for lesser deformities, especially in the frontal part of the cervicocapital junction. The study on the cadavers  showed that resection of more than 30% of the anterolateral part of the cervicocapital junction has a risk of iatrogenic fracture in FAI cam type. It is usually sufficient to resect 20% of the cervicocapital junction.
Ganz et al  performed 213 luxations of the hip joint and included 19 patients who underwent simultaneous intertrochanteric osteotomy. In 1.4% of hips, revision for nonunion osteotomy ground trochanter was required. Although none of the patients developed avascular necrosis during the follow-up, 37% of patients experienced the development of heterotopic ossifications. Murphy et al  did open surgery to treat FAI in 23 patients, and 30% of patients eventually required total hip replacement. Beck et al  also treated 19 patients with FAI, and 26% of patients later needed total hip replacement. We found in our patient series that total hip replacement was not need during the follow-up period.
The majority of studies do not show any complications regarding necrosis of the femoral head, and in the short-term follow-up, the patients experience clinical relief. However, they are lacking long-term follow-up. It is evident that early correction of FAI leads to better function of the hip movement. Unfortunately, it is not clearly known how often this correction leads to prevention of arthritis of the hip joint.