Significant improvement in quality-of-life parameters has been shown in the treatment of isolated cam deformity by open surgical dislocation and osteochondroplasty. Beaule et al. [4] followed a cohort of 37 hips in 34 patients with a WOMAC, UCLA, and SF-12 score at a mean of 3.1 years. Preoperative markers confirmed that FAI has a significant negative impact on quality of life, even with the absence of radiographic arthritis. In this group, 28 of 34 patients showed improvement in all clinical outcome scores and were either satisfied or very satisfied with the surgical outcome. Of the patients who had poor results, the Tönnis grade and the amount of chondral damage at the time of surgery was increased, further supporting the recommendation to avoid hip preservation surgery in arthritic hips. Despite the encouraging early clinical results, there were a significant number of reoperations for hardware removal and trochanteric complications.

Graves and Mast [14] followed a cohort of 48 hips in 46 patients with postsurgical hip dislocation, studying the Merle D’Aubigne-Postel score, rate of trochanteric nonunions, and incidence of femoral neck fracture. Surgical hip dislocation was performed through the Gibson approach, and an osteochondroplasty was performed at the femoral head-neck junction. In some patients, additional procedures were indicated, including relative neck lengthening, intertrochanteric osteotomy, lateralization of the GT, osteochondral allografting, osteophyte resection, sciatic neurolysis, and loose body removal. A total of 96 % of patients showed improvement at the final follow-up of an average of 38 months, by means of clinical outcomes scores and radiographic restoration of head-neck offset. Nine of the 48 patients had at least grade one heterotopic ossification (ossification islands around the hip) formation, but no nonunions occurred, and two patients required screw removal. Peters and Erickson [19] had similar results in a review of 30 hips in 29 patients who underwent a debridement by means of surgical hip dislocation. These patients were followed for a mean of 2 years and showed an improvement in HHS from 70 to 87 points. Eight hips showed radiographic progression of arthritis, with 4 patients progressing to hip arthroplasty. As with the previous series, those patients requiring a secondary procedure to convert to total hip arthroplasty had more severe cartilage damage on initial presentation.

Mardones et al. [16] investigated the structural effect of surgical resection of the head-neck junction on the risk of postoperative femoral neck fractures. The amount of femoral neck that could be safely resected was studied using cadaveric specimens. Osteochondroplasty was performed using a surgical dislocation as per Ganz with a saw and burr using an appropriately sized plastic template to confirm sphericity. The peak load to fracture was significantly reduced in specimens with greater than 50 % of the neck resected, while the 10 % and 30 % resections were equal.

The treatment of high-level athletes with FAI is a challenge given the need to return to professional level of sporting activity and the unique motivations of these patients. Naal et al. [17] looked specifically at the outcomes of professional athletes undergoing debridement of cam and mixed lesions treated with open surgical hip dislocation. A series of 30 hips in 22 athletes were followed at an average of 45.2 months postoperatively with return to professional-level sporting activity being the primary outcome. In this patient group, 96 % were able to return to prior level of sporting activity, with 18 of 22 patients being satisfied or very satisfied with the outcome. Improvements were seen also in the SF-12, UCLA, HOS, HHS, and Tegner scale and a unique sports activity score. Patients had an average improvement of the alpha angle from 69.3 to 43.4 and the internal rotation of 6–14.5°. As with prior series, a significant rate of trochanteric complications was seen, with 20 % of patients requiring removal of the screws. No cases of AVN were recorded, and only one patient showed progression of their Tönnis grade. Results were comparable to hip arthroscopy and hip dislocation in a nonprofessional athlete population. These authors suggest that surgical hip dislocation may be preferable to other techniques as it allows for access to lesions that may be difficult to treat arthroscopically and may justify the increased recovery time and complication rate.

Unique complications of open surgical hip dislocation include the incidence of nonunion of the greater trochanteric osteotomy and symptomatic hardware from the trochanteric fixation. The rate of secondary procedures is higher than other techniques, mostly due to the need for screw removal in a significant number of patients, which is required in up to 20 % of patients ([17], Yun et al. [21]). This procedure also carries the risk of avascular necrosis of the femoral head. However, no cases of AVN were reported in the original series of patients reported by Ganz et al. [12]. Clinically significant heterotopic ossification, sciatic nerve injury, and progression of arthritis have also been reported.

Multiple minimally invasive approaches to the hip joint for the treatment of cam deformities have also been well described in the literature [1, 8, 10]. The proposed benefits of this procedure include direct visualization of cam lesions without the morbidity associated with a surgical dislocation and the avoidance of complications associated with traction and the steep learning curve and expertise required for adequate resection by means of hip arthroscopy. The most commonly utilized techniques include the mini-open anterior approach described by Cohen et al. [10] and the Hueter technique described by Barton et al. [1] or Chiron et al. [8].

A minimally invasive anterior approach for the treatment of FAI has been described by Cohen et al. [10]. A 2–3 cm incision is made 2 cm distal and posterior to the anterior superior iliac spine (ASIS), in line with the medial border of the TFL muscle belly. Dissection is carried down to expose the medial fatty stripe of the Smith-Peterson interval. The fascia of the TFL is incised along the medial edge, and dissection is continued bluntly to palpate the femoral neck, around which blunt retractors are placed to expose the capsule. Pericapsular fat is excised, and the interval between the rectus and capsule is developed with a Cobb elevator. A final sharp Hohmann retractor is placed over the anterior acetabular rim to expose the entire capsule. A T-shaped capsule incision is made oriented proximally to expose the acetabulum and head-neck junction. The retractors are then repositioned within the capsule to expose the acetabular margin and the anterior femoral head. The exposure may be improved by having an assistant apply longitudinal traction and rotation to the limb. Bone is resected at the area of impingement using osteotomes and a 5 mm burr. Resection is completed when impingement is no longer observed during dynamic assessment with the hip brought through a full range of motion.

A second minimally invasive approach using the Hueter technique has also been published [1]. This approach utilizes a vertical incision starting 2 cm distal to the ASIS and extending 3–4 cm distally along the medial aspect of the TFL muscle. The fascia of the TFL is incised along the medial fibers and it is retracted laterally. Dissection is continued bluntly within the sheath of the TFL to avoid damage to the LFCN. Once the deep fascia of the TFL is exposed, the fascia in the interval between the gluteus medius and rectus femoris is exposed. The reflected head of the rectus can be retracted laterally to expose the underlying capsule without further muscle dissection. A proximally based T- or L-shaped capsular incision is then used to expose the acetabular rim and is reflected laterally to visualize the labrum and the femoral head-neck junction. Blunt retractors are placed around the femoral neck to enhance the exposure of the head-neck junction. At this point, the hip is brought into a position of impingement and the area of abutment is confirmed at the acetabular rim. Osteochondroplasty is completed as previously described with a combination of osteotomes and a high-speed burr. The extent of resection is determined by recreation of a smooth head-neck contour and an impingement-free range of motion.