LETTERS TO THE EDITOR
Vascularized Bone Grafting and Distal Radius Osteotomy for Scaphoid Nonunion Advanced Collapse: Myth and Reality To the Editor: I read with much interest the article by Malizos and colleagues.1 Based on previous studies by Giannikas et al,2 they assumed that a closing-wedge osteotomy of the distal radius by shortening the radial column theoretically shifts the stress and load away from the scaphoid. This, in turn, would relieve pain in scaphoid nonunion advanced collapse, grade I to III. However, this hypothesis has not yet been demonstrated in the medical literature and remains controversial. Because the scaphoid is still attached to the distal radius by means of ligamentous structures, the closing wedge osteotomy would shift only marginally the area of contact between the radius and scaphoid and would hardly relieve the amount of pressure exerted onto the scaphoid as a whole. I wonder whether pain is actually relieved by the denervation that this procedure implies, rather than the hypothetical shift of load and stress. Often we tend to overestimate the effectiveness of many of our operations to treat articular pain based on their hypothetical modifications on joint biomechanics, when in many cases pain is simply relieved by the denervation that these procedures imply, usually through generous and wide dissections. Joan Arenas-Prat, MD Pulvertaft Hand Centre Royal Derby Hospital Derby, UK http://dx.doi.org/10.1016/j.jhsa.2014.05.037 REFERENCES 1. Malizos KN, Koutalos A, Papatheodorou L, Varitimidis S, Kontogeorgakos V, Dailiana Z. Vascularized bone grafting and distal radius osteotomy for scaphoid nonunion advanced collapse. J Hand Surg Am. 2014;39(5):872e879. 2. Giannikas AC, Papachristou G. Wedge osteotomy of the lower end of the radius in the treatment of painful pseudoarthrosis of the carpal scaphoid bone. Clin Orthop Relat Res. 1989;(246):16e21.
that the effect of the wedge osteotomy on wrist joint biomechanics is only hypothetical. However, it has been shown from biomechanical studies in the wrist that osteotomies can reliably shift load away from the area of interest (scaphoid and lunate). In the scaphoid, the effect of wedge osteotomy of the radius has been studied on anatomic specimens in which it was found that the scaphoid remained unloaded after a wedge osteotomy, although a load of 10 kg was applied to the wrist (Papachristou et al. Contact areas of the wrist joint. 15th Hellenic Autumn Orthopaedic meeting, Athens, Greece, 1983), and a clinical study demonstrated the effect of osteotomy in cases of painful scaphoid nonunion.2 In the lunate, a biomechanical analysis on cadaveric wrists demonstrated a 26% decrease on lunate cortical strain after a radial opening wedge osteotomy.3 Furthermore, the elastic properties of the wrist ligaments and the existence of mechanoreceptors in the carpal ligaments4,5 safely allow widening of the radioscaphoid joint as was observed in our series (Fig. 1A, B). Concerning denervation of the wrist, we would like to point out that extensive denervation should be avoided especially in cases of advanced osteoarthritis.5 In addition, the entire procedure described in our article is performed with limited dissection under magnification and involves only the radial side of the distal radius, protecting wrist joint innervation, whereas the fixation is minimal (usually with Steinmann pins), in contrast to denervation procedures reported in the literature that require extensive dissection.6 Finally, as was underlined in our study, it is difficult to clarify which components of the procedure (vascularized bone grafting, restoration of scaphoid anatomy, or wedge osteotomy) contribute most to the success of the procedure. Zoe Dailiana, MD, PhD Konstantinos N. Malizos, MD, PhD Antonios Koutalos, MD Department of Orthopaedic Surgery and Musculoskeletal Trauma
In Reply: We would like to thank the author for the comments on our article.1 The author raises the concern
Ó 2014 ASSH
r
Published by Elsevier, Inc. All rights reserved.
r
1885
Vascularized Bone Grafting and Distal Radius Osteotomy for Scaphoid Nonunion Advanced Collapse: Myth and Reality To the Editor: I read with much interest the article by Malizos and colleagues.1 Based on previous studies by Giannikas et al,2 they assumed that a closing-wedge osteotomy of the distal radius by shortening the radial column theoretically shifts the stress and load away from the scaphoid. This, in turn, would relieve pain in scaphoid nonunion advanced collapse, grade I to III. However, this hypothesis has not yet been demonstrated in the medical literature and remains controversial. Because the scaphoid is still attached to the distal radius by means of ligamentous structures, the closing wedge osteotomy would shift only marginally the area of contact between the radius and scaphoid and would hardly relieve the amount of pressure exerted onto the scaphoid as a whole. I wonder whether pain is actually relieved by the denervation that this procedure implies, rather than the hypothetical shift of load and stress. Often we tend to overestimate the effectiveness of many of our operations to treat articular pain based on their hypothetical modifications on joint biomechanics, when in many cases pain is simply relieved by the denervation that these procedures imply, usually through generous and wide dissections. Joan Arenas-Prat, MD Pulvertaft Hand Centre Royal Derby Hospital Derby, UK http://dx.doi.org/10.1016/j.jhsa.2014.05.037 REFERENCES 1. Malizos KN, Koutalos A, Papatheodorou L, Varitimidis S, Kontogeorgakos V, Dailiana Z. Vascularized bone grafting and distal radius osteotomy for scaphoid nonunion advanced collapse. J Hand Surg Am. 2014;39(5):872e879. 2. Giannikas AC, Papachristou G. Wedge osteotomy of the lower end of the radius in the treatment of painful pseudoarthrosis of the carpal scaphoid bone. Clin Orthop Relat Res. 1989;(246):16e21.
that the effect of the wedge osteotomy on wrist joint biomechanics is only hypothetical. However, it has been shown from biomechanical studies in the wrist that osteotomies can reliably shift load away from the area of interest (scaphoid and lunate). In the scaphoid, the effect of wedge osteotomy of the radius has been studied on anatomic specimens in which it was found that the scaphoid remained unloaded after a wedge osteotomy, although a load of 10 kg was applied to the wrist (Papachristou et al. Contact areas of the wrist joint. 15th Hellenic Autumn Orthopaedic meeting, Athens, Greece, 1983), and a clinical study demonstrated the effect of osteotomy in cases of painful scaphoid nonunion.2 In the lunate, a biomechanical analysis on cadaveric wrists demonstrated a 26% decrease on lunate cortical strain after a radial opening wedge osteotomy.3 Furthermore, the elastic properties of the wrist ligaments and the existence of mechanoreceptors in the carpal ligaments4,5 safely allow widening of the radioscaphoid joint as was observed in our series (Fig. 1A, B). Concerning denervation of the wrist, we would like to point out that extensive denervation should be avoided especially in cases of advanced osteoarthritis.5 In addition, the entire procedure described in our article is performed with limited dissection under magnification and involves only the radial side of the distal radius, protecting wrist joint innervation, whereas the fixation is minimal (usually with Steinmann pins), in contrast to denervation procedures reported in the literature that require extensive dissection.6 Finally, as was underlined in our study, it is difficult to clarify which components of the procedure (vascularized bone grafting, restoration of scaphoid anatomy, or wedge osteotomy) contribute most to the success of the procedure. Zoe Dailiana, MD, PhD Konstantinos N. Malizos, MD, PhD Antonios Koutalos, MD Department of Orthopaedic Surgery and Musculoskeletal Trauma
In Reply: We would like to thank the author for the comments on our article.1 The author raises the concern
Ó 2014 ASSH
r
Published by Elsevier, Inc. All rights reserved.
r
1885
