M.J. Coughlin and C.P. Jones reply:
We thank Dr. Greisberg for his letter and comments, and we appreciate the opportunity to clarify a number of facts that we reported in our paper.
The purpose of our prospective clinical series was not to define the etiology of hallux valgus deformities. This is a topic of great interest for all of us but is a subject that is no closer to being defined now than in Morton's era. In our study, we evaluated the clinical and radiographic results of one surgical approach (distal soft-tissue realignment with proximal crescentic osteotomy) as a treatment for moderate and severe bunion deformities. We quantified the effect of this procedure on clinical and radiographic metatarsocuneiform joint mobility, something that had not been done before.
Dr. Greisberg states that the Klaue device1 has not been validated. He is incorrect, and we call to his attention the articles by Jones et al.2 and Glasoe et al.3. The Klaue device1, although not widely used other than as a research device, was designed and described by Klaue and Hansen1 and is a means with which to objectively quantify first ray sagittal excursion. Our results with use of this validated device demonstrate that there is an association between increased first ray mobility and hallux valgus deformities, that so-called "first ray hypermobility" does not necessitate a Lapidus procedure for a successful outcome, and that first ray mobility is routinely and significantly reduced following a distal realignment and first metatarsal osteotomy without a metatarsocuneiform arthrodesis.
"Hypermobility" may be conceptual, as Dr. Greisberg suggests, but this is not a valid scientific description and the manual examination of first ray mobility does not allow quantification. Many articles have been published with no substantiation of first ray mobility other than the authors' clinical impression4-11. We agree with Dr. Greisberg that it has been described, defined, and taught for many years. However, we agree with Glasoe et al.3 that this notion is based on an unreliable manual clinical examination.
Dr. Greisberg suggests that a Lapidus procedure is a logical solution as it addresses the first ray malalignment at the point of deformity. A proximal crescentic osteotomy, using the center of rotation axis (CORA), also achieves its correction at the metatarsocuneiform joint. Contrary to Dr. Greisberg's notion, a metatarsal osteotomy does not necessarily create a secondary deformity. We do agree with him that a Lapidus procedure has many downsides, including slow healing, occasional nonunion, and potential technical difficulties during the procedure. Furthermore, Dr. Greisberg misses the point in our article regarding the result of the metatarsal osteotomy. The transarticular fixation was temporary (six weeks in duration), and we submit that the first ray realignment was the main reason for the diminution in first ray mobility.
As Dr. Greisberg comments, there are many unanswered questions. For many years, proponents of the Lapidus procedure have accepted Morton's and Lapidus' theories of first ray hypermobility without critical investigation of their merits. These are questions that we have asked and tried to answer, and we concluded that "we found little clinical evidence to substantiate [their] theories."
It is unclear whether hallux valgus deformities develop secondary to metatarsus primus varus, or vice versa. Similarly, it is unknown whether increased mobility at the first metatarsocuneiform joint predisposes to subluxation in the axial plane or is a secondary effect of a wide intermetatarsal angle. Additionally, a deviated or subluxated joint, in our opinion, does not necessarily equate to an unstable or hypermobile joint, as Dr. Greisberg suggests. Deformities often develop slowly over time and may be inherently stiff, despite attenuation of the capsule and other soft-tissue structures. Regardless, our study does not settle these "chicken versus the egg" debates, but it does provide important clinical support for joint-sparing procedures, even in the setting of increased preoperative mobility.
We recognize that the Lapidus procedure does address the deformity at its proximal apex and provides powerful correction of a widened intermetatarsal angle. We find this a useful operation and utilize it when appropriate. On the other hand, we believe we have answered one question with our quantification of first ray motion after a distal realignment and we conclude that a first metatarsocuneiform joint arthrodesis is not necessary to achieve realignment of the first ray and reduction of first ray mobility. We have effectively challenged the theories of Morton and Lapidus, and we conclude that the Lapidus procedure is not the only approach to first ray "hypermobility." We believe that we are asking appropriate questions, indeed the right questions, but it will take many more studies to have all of the answers.
These letters originally appeared, in slightly different form, on . They are still available on the web site in conjunction with the article to which they refer.