Abstract
The excitement and enthusiasm that accompanies the introduction of many new technologies and techniques can be self-sustaining, meaning that the appeal of doing something new or different (not necessarily doing something better) becomes the prime driver. Such is likely the case today with the direct anterior approach to total hip arthroplasty. Can THA be done successfully through a direct anterior approach? Certainly the answer is yes; and with experience it can be done in relatively broad groups of patients with an acceptable risk of complications. Is it a better way to do THA than other approaches? Well probably not in 2012.
Contemporary THA done with a variety of approaches and coupled with advanced anesthetic, pain management and rapid rehabilitation protocols has been shown to be safe and effective with both short hospital stays (48 hours) and even outpatient surgery in selected patients. No substantial clinical advantage has been shown to date with a direct anterior approach. The sometimes extraordinary claims associated with the direct anterior approach are accompanied by relatively ordinary data.
The purported benefits of direct anterior related to more rapid recovery, better function, or a lower dislocation risk just have not proved to be demonstrable in broad groups of patients. In regard to recovery there are now several studies suggesting no difference at 2 hours; 2 days; 2 weeks or 2 years after surgery; and likely no difference at 2 months either. In regard to function there are now multiple gait analysis studies with no demonstrable benefit at 2 weeks or 6 weeks. In regard to lower risk of dislocation if we pool the data from big published studies Sariali (1.5%) Matta (0.6%) Jewett (1%) and Woolson (0%) the mean is 0.88%. Interestingly, contemporary posterior approach THA with formal capsular repair also has <1% dislocation rate when we look at published data from White (0.5%) Pagnano (0.3%) and Dorr (0%).
The direct anterior does come at a cost including: longer operative times; additional equipment and/or personnel; unique complications; and in some techniques the need for intra-operative fluoroscopy with attendant exposure to radiation for the surgeon and staff.
It is clear in 2012 that the direct anterior approach is just another technique for performing a very successful procedure, namely total hip arthroplasty. With advanced anesthetic, pain management, and rapid rehabilitation protocols it will be extremely difficult to prove any marginal benefit associated with THA surgical technique. To summarize the available data on direct anterior THA it is not unreasonable to conclude that “the extraordinary claims are accompanied by very ordinary data.”
