Editorial Comment

The Eighth Combined Open Scientific Meeting of the Hip Society and the American Association of Hip and Knee Surgeons features seven distinctive sessions. The first six subject areas presented an innovative format, initiated by a basic science or “what we have learned” seminal lecture, followed by several alternative treatment papers relevant to the principal topic. This method of presentation encouraged the speakers to state their position and surgical results emphatically and defend their views in lively discussion. Some articles were devoted to issues pertinent and unique to osteoarthritis in the geriatric, the middle-aged, and the young patient.

Advanced hip arthritis in the elderly patient presents challenges regarding bone quality, implant stability, and patient cognitive function. These issues were discussed in talks devoted to surgical approach, bearing surface head size and constraint, and cost-effective implant matching.

The middle-aged patient with osteoarthritis is much more informed and has higher expectations than in the past. The challenges in this group include issues of component fixation, the bearing surface couple, and wear-related osteolysis. To address these concerns, two successive talks were given on autopsy retrievals of long-term functioning femoral implants. The case for proximally versus extremity coated porous stems and cemented hybrid fixation was presented.

The young patient with hip disease presents, in many ways, the most formidable challenge to the treating orthopaedist. Many of these patients have developmental abnormalities such as developmental dysplasia of the hip, slipped capital femoral epiphysis, or osteonecrosis. To address these issues, there was a detailed presentation about the natural history of developmental dysplasia and its consequences on hip biomechanics. The current research on glucosamine and other nutraceuticals also was discussed. The latest developments in joint-preserving surgery were highlighted, especially regarding osteotomy and hip arthroscopy. Hip reconstruction, whether by surface replacement or total joint arthroplasty, may require special surgical approaches, such as subtrochanteric femoral osteotomy in patients with Crowe 4 developmental dysplasia of the hip. In addition, the geometric and size variations in this patient population are considerable, requiring technical expertise.

The Presidential Guest speaker, Dr. Philippe Hernigou, gave a stimulating and provacative dissertation on the use of autologous bone marrow grafting for the treatment of osteonecrosis. Three seminal papers were presented on implant topography with and without hydroxyapatite, the effect of viscosity on cement pressurization and intrusion, and bearing surface couplings: metal-on-metal versus metal-on-polyethylene. The latter prospective randomized trial results were concerning because the metal-on-metal articulation cohort was aborted early because of very high systemic ion levels.

The fifth session examined the implant bearing surface articulation in detail. Lessons learned from laboratory science such as head size variations and their effects on functional torque and polyethylene thickness and the effects of different methods of cross-linking on wear were discussed. Subsequent topics focused on osteolysis: particulate generation and access to the effective joint space, particle migration as a result of intraarticular pressure and capsular compliance variations, and the reaction of tissues to particles and their products.

The remaining talks addressed the rationale and results of using 22-, 28-, 32-, 36-, and 42-mm femoral heads at the articulation. Finally, alternative bearings, metal-on-metal and ceramic-on-ceramic, were examined, their methodology was discussed, and their clinical consequences were reviewed.

Session 6 focused on the late sequelae of hip trauma. One author’s extensive experience with the articular and bony changes after acetabular fractures was reviewed. The rationale and techniques for anatomic fixation and its long-term results were discussed. Also, the unique challenge of total hip arthroplasty after acetabular fracture, whether done early or late, was presented.

The final session focused on hip surgery in the future. An eloquent review of hip-related research from the Orthopaedic Research Society was presented. Additional presentations were given, primarily in video format, on mini-incision total hip arthroplasty, computed tomography scanning and computer planning for periacetabular osteotomy, surgical navigation for acetabular component positioning, and virtual reality hip surgery.

The quality of these presentations given in this open meeting and the wealth of experience that these topics represent was outstanding. I would like to thank the authors for their expertise and hard work and Drs. Richard White and Benjamin Bierbaum for their collaboration in the development of this program.