Commentary & Perspective

Commentary & Perspective on
"Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fractures"
by Antonio Moroni, MD, et al.

Commentary & Perspective by
J. Lawrence Marsh, MD*,
University of Iowa Hospitals and Clinics, Iowa City, Iowa

The enthusiasm of surgeons for treating fractures with external fixation has waxed and waned over decades. Although new innovations in external fixation technology have been developed at the same time as innovations and improved techniques for internal fixation, surgeons have tended to favor internal fixation methods because external fixation has always had the disadvantage of a persistent rate of pin-tract problems and patient intolerance of external frames.

The authors of two recent studies, one of which was a randomized controlled trial, have reported good results with use of external fixation in the treatment of fractures of the proximal aspect of the femur in elderly patients and have suggested that external fixation has advantages when compared with the traditional techniques^1,2. Despite these reports, most surgeons perceive that the risk of poor fixation in the proximal aspect of the femur combined with the potential for intractable pin-tract infection is a problem of such magnitude that it precludes external fixation of hip fractures from being a viable treatment technique in their practice. The article by Moroni et al. may cause some surgeons to reconsider these negative perceptions.

The authors of this small, randomized controlled trial of patients with osteoporotic hip fracture have compared a group of patients who were treated with external fixation with hydroxyapatite-coated external fixation pins with an equivalent group of patients who were treated with a compression screw and side plate. At six months after treatment, they found similar patient outcomes when comparing outcome parameters such as the radiographic neck-shaft angle and the Harris hip score. Patients treated with the percutaneous external fixator compared with those treated with open reduction and internal fixation had significant advantages in the early perioperative period: a shorter operative time, less blood loss and need for transfusion, and less pain five days after surgery. Even more importantly, there was no evidence of patient intolerance of the frame, poor fixation, or intractable pin-tract problems. Postoperative follow-up visits were similar in both groups. Each group had one mechanical failure, and there were no pin-tract infections recorded.

This article is further evidence of the mechanical value of a hydroxyapatite coating on external fixation pins. The absence of mechanical failures and pin-tract problems is very impressive and different from what would be expected with traditional pins in patients with osteoporosis of the proximal aspect of the femur. The authors reported that neither sedation nor anesthesia was necessary to remove external fixation pins at the end of treatment, although increased pain at removal has been reported³ and, in my experience, has occasionally led to operative removal of frames where this otherwise would not have been required. The routine need for an additional operative procedure would be a substantial negative factor that would detract from these otherwise very positive results.

Although the results of this study are impressive, there are a few issues that might cause surgeons to consider whether these results would apply to their practice. First, this study included only a relatively small number of patients with unstable fracture patterns. In unstable patterns, the sliding capabilities of the screw-and-plate device provide mechanical advantages that may not be duplicated by external fixation. This fact does not detract from the findings of this study but means that it is possible that the results may not be generalized to a larger series of more demanding fracture patterns. Another issue is the complete absence of pin-tract problems, a result so good that it may lead surgeons who are used to seeing frequent pin-tract problems to have concern that these results could not possibly be reproduced in their hands. Finally, the shorter operating times in the external fixation group may partially reflect the skill of the operative team in performing external fixation techniques, since it must not be easy for those inexperienced with the technique to percutaneously place two external fixation pins into the femoral neck. If there is a substantial learning curve to accurate pin placement, the advantage of decreased operative time seen by these authors will not be realized by less experienced surgeons, and it is likely that other outcome measures could be negatively affected if less accurately placed pins were accepted.

In summary, this randomized controlled trial demonstrated potential benefits of external fixation for patients with osteoporotic fractures of the proximal femur. The potential advantages of percutaneous approaches without canal manipulation are considerable and, if complications can be minimized as they were in this study, increased use of this technique might lead to widespread patient benefit. We should welcome further study from the authors, and it would be particularly interesting to know their ongoing experience with the most unstable fracture patterns.

*The author did not receive grants or outside funding in support of the research or preparation of this manuscript. He did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the author is affiliated or associated.

References

1. Vossinakis IC, Badras LS. The external fixator compared with the sliding hip screw for pertrochanteric fractures of the femur. J Bone Joint Surg Br. 2002;84:23-9.
2. Vossinakis IC, Badras LS. Management of pertrochanteric fractures in high-risk patients with an external fixation. Int Orthop. 2001;25:219-22.
3. Moroni A, Aspenberg P, Toksvig-Larsen S, Falzarano G, Giannini S. Enhanced fixation with hydroxyapatite coated pins. Clin Orthop. 1998;346:171-7.

Copyright © 2005 by the The Journal of Bone and Joint Surgery, Inc.