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A Rare Case of a Vertical Oblique Scaphoid Fracture Nonunion
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LETTERS TO THE EDITOR
A Rare Case of a Vertical Oblique Scaphoid Fracture Nonunion To the Editor: Three-dimensional computed tomography (CT) modeling enables accurate evaluation of fracture plane orientation in scaphoid fractures. Recently, Luria et al1 used this technique in 124 scaphoid fractures and concluded that practically all fractures were horizontal oblique, and not transverse. We wish to report an unusual case of a vertical oblique (VO) scaphoid fracture—a distinct subgroup in Russe’s classification.2 After punching a boxing ball, a 17-yearold male patient presented to the emergency department with immediate right-sided wrist pain. Radiographs (Fig. 1A) and an additional technetium bone scan indicated a proximal scaphoid fracture, which was immobilized for 12 weeks. Follow-up radiographs showed fracture union. Nine years later, he was referred to our tertiary center, due to, again, right-sided wrist complaints. A CT scan showed a proximal VO fracture nonunion (Fig. 1B), which was satisfactorily treated with proximal row carpectomy because of painful osteoarthritis. VO fractures are rare (<5% of scaphoid fractures) and typically caused by an axial loading injury.3,4 They are notorious for their misinterpretation on plane radiographs.4 Therefore, we recommend using a CT scan to evaluate the acute fracture morphology and, in direct follow-up, bony consolidation. If an acute VO fracture is recognized, we also recommend using immediate screw fixation because of its unstable nature and higher risk to nonunion.4 VO fractures may need a distinct surgical plan. To analyze optimal screw placement, we retrospectively used the nonunion CT scan to obtain 3-dimensional CT
models of the fragments, and virtually realigned them using the intact scaphoid as template (Fig. 1C). After obtaining a standardized midsagittal fracture outline,5 the fracture angle relative to the central scaphoid axis was calculated to be 65 (Fig. 1D). Thus, theoretically, only a screw placed 25 eccentrically to the scaphoid central axis would allow for a position perpendicular to the fracture line, which is associated with favorable fixation stability.1 Paul W. L. ten Berg, MD* Simon D. Strackee, MD, PhD* *Department of Plastic, Reconstructive, and Hand Surgery Academic Medical Center University of Amsterdam Amsterdam, The Netherlands http://dx.doi.org/10.1016/j.jhsa.2015.09.019 REFERENCES 1. Luria S, Schwarcz Y, Wollstein R, Emelife P, Zinger G, Peleg E. 3Dimensional analysis of scaphoid fracture angle morphology. J Hand Surg Am. 2015;40(3):508e514. 2. Russe O. Fracture of the carpal navicular. Diagnosis, non-operative treatment, and operative treatment. J Bone Joint Surg Am. 1960;42A:759e768. 3. Brondum V, Larsen CF, Skov O. Fracture of the carpal scaphoid: frequency and distribution in a well-defined population. Eur J Radiol. 1992;15(2):118e122. 4. Herzberg G, Forissier D, Falaise C. Coronal fractures of the proximal scaphoid: the proximal ring sign. J Hand Surg Br. 2003;28(5):500e503. 5. ten Berg PW, Dobbe JG, Strackee SD, Streekstra GJ. Quantifying scaphoid malalignment based upon height-to-length ratios obtained by 3dimensional computed tomography. J Hand Surg Am. 2015;40(1):67e73.
FIGURE 1: A Initial anteroposterior radiograph of the right wrist after the acute injury. B Sagittal CT image showing a proximal scaphoid nonunion with a VO fracture line. C Three-dimensional CT model of the virtually realigned nonunion fragments. Based on the scaphoid inertial axes, the central axis (green line) and dorsal-to-volar axis (red line) were used to cross-section the fragments in the midsagittal plane. D Midsagittal outline showing the angle (65 ) between a line fitted through the VO fracture sites and the central axis.
J Hand Surg Am.
r
Vol. 41, January 2016
LETTERS TO THE EDITOR
A Rare Case of a Vertical Oblique Scaphoid Fracture Nonunion To the Editor: Three-dimensional computed tomography (CT) modeling enables accurate evaluation of fracture plane orientation in scaphoid fractures. Recently, Luria et al1 used this technique in 124 scaphoid fractures and concluded that practically all fractures were horizontal oblique, and not transverse. We wish to report an unusual case of a vertical oblique (VO) scaphoid fracture—a distinct subgroup in Russe’s classification.2 After punching a boxing ball, a 17-yearold male patient presented to the emergency department with immediate right-sided wrist pain. Radiographs (Fig. 1A) and an additional technetium bone scan indicated a proximal scaphoid fracture, which was immobilized for 12 weeks. Follow-up radiographs showed fracture union. Nine years later, he was referred to our tertiary center, due to, again, right-sided wrist complaints. A CT scan showed a proximal VO fracture nonunion (Fig. 1B), which was satisfactorily treated with proximal row carpectomy because of painful osteoarthritis. VO fractures are rare (<5% of scaphoid fractures) and typically caused by an axial loading injury.3,4 They are notorious for their misinterpretation on plane radiographs.4 Therefore, we recommend using a CT scan to evaluate the acute fracture morphology and, in direct follow-up, bony consolidation. If an acute VO fracture is recognized, we also recommend using immediate screw fixation because of its unstable nature and higher risk to nonunion.4 VO fractures may need a distinct surgical plan. To analyze optimal screw placement, we retrospectively used the nonunion CT scan to obtain 3-dimensional CT
models of the fragments, and virtually realigned them using the intact scaphoid as template (Fig. 1C). After obtaining a standardized midsagittal fracture outline,5 the fracture angle relative to the central scaphoid axis was calculated to be 65 (Fig. 1D). Thus, theoretically, only a screw placed 25 eccentrically to the scaphoid central axis would allow for a position perpendicular to the fracture line, which is associated with favorable fixation stability.1 Paul W. L. ten Berg, MD* Simon D. Strackee, MD, PhD* *Department of Plastic, Reconstructive, and Hand Surgery Academic Medical Center University of Amsterdam Amsterdam, The Netherlands http://dx.doi.org/10.1016/j.jhsa.2015.09.019 REFERENCES 1. Luria S, Schwarcz Y, Wollstein R, Emelife P, Zinger G, Peleg E. 3Dimensional analysis of scaphoid fracture angle morphology. J Hand Surg Am. 2015;40(3):508e514. 2. Russe O. Fracture of the carpal navicular. Diagnosis, non-operative treatment, and operative treatment. J Bone Joint Surg Am. 1960;42A:759e768. 3. Brondum V, Larsen CF, Skov O. Fracture of the carpal scaphoid: frequency and distribution in a well-defined population. Eur J Radiol. 1992;15(2):118e122. 4. Herzberg G, Forissier D, Falaise C. Coronal fractures of the proximal scaphoid: the proximal ring sign. J Hand Surg Br. 2003;28(5):500e503. 5. ten Berg PW, Dobbe JG, Strackee SD, Streekstra GJ. Quantifying scaphoid malalignment based upon height-to-length ratios obtained by 3dimensional computed tomography. J Hand Surg Am. 2015;40(1):67e73.
FIGURE 1: A Initial anteroposterior radiograph of the right wrist after the acute injury. B Sagittal CT image showing a proximal scaphoid nonunion with a VO fracture line. C Three-dimensional CT model of the virtually realigned nonunion fragments. Based on the scaphoid inertial axes, the central axis (green line) and dorsal-to-volar axis (red line) were used to cross-section the fragments in the midsagittal plane. D Midsagittal outline showing the angle (65 ) between a line fitted through the VO fracture sites and the central axis.
J Hand Surg Am.
r
Vol. 41, January 2016