SCIENTIFIC ARTICLE
The Unstable Nonunited Scaphoid Waist Fracture: Results of Treatment by Open Reduction, Anterior Wedge Grafting, and Internal Fixation by Volar Buttress Plate Adel Ghoneim, MD Purpose The purpose of this study is to evaluate the results of treatment of unstable nonunited scaphoid waist fracture by anterior wedge graft and internal fixation with the use of volar buttress plate and screws. Methods Fourteen adult male patients with unstable nonunited scaphoid waist fracture with a humpback deformity were treated by reduction of the collapse deformity, insertion of anterior wedge graft, and internal fixation with the use of volar buttress plate and screws. The mean patient age was 26 years, and the mean duration of the nonunion before surgery was 16.5 months. The follow-up time ranged from 9 to 19 months (mean, 11 mo). Thirteen of the fourteen nonunions healed with sound radiographic union. Pre-existing avascular necrosis was a major adverse factor for achievement of union in one patient, even after a second bone-grafting procedure. Results Union was achieved in a mean of 3.8 months. Most of the patients had satisfactory correction of scaphoid deformity and the associated dorsal intercalated segment instability. Postoperatively, improvements were seen in the range of wrist flexion and extension, grip strength, and degree of dorsal intercalated segment instability. Conclusions The results of the series suggest that the method of anterior wedge graft and internal fixation with the use of volar buttress plate and screws is effective for the treatment of unstable nonunited scaphoid waist fractures. (J Hand Surg 2011;36A:17–24. Copyright © 2011 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic IV. Key words Scaphoid buttress plating, scaphoid waist nonunion, plate fixation. fractures (volar type) are predisposed to fracture collapse and nonunion. The edges of the proximal and distal pole fragments abut each other and, after repeated cy-
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NSTABLE SCAPHOID WAIST
From the Department of Orthopedic Surgery, Suez Canal University, Ismailia, Egypt. Received for publication February 18, 2010; accepted in revised form October 4, 2010. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Adel Ghoneim, MD, Department of Orthopedic Surgery, Suez Canal University, 58 Mohamed Ali St, Ismailia 41511, Egypt; e-mail:
[email protected]. 0363-5023/11/36A01-0004$36.00/0 doi:10.1016/j.jhsa.2010.10.003
cles of loading, experience progressive erosion and bone loss. The scaphoid nonunion collapses into a humpback deformity and the rest of the carpals into a dorsal intercalated segment instability (DISI) pattern that must be corrected.1– 4 At present, agreement has been reported about the 3-step principle of management of the nonunited scaphoid wrist collapse with DISI: open reduction, length restoration by interpositional anterior wedge grafting, and internal fixation by screw.3–10Although it was found that Herbert screw fixation gave a higher success rate in achieving bony union with better functional results, the technical difficulty and the need to release
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the scaphotrapezial ligament were addressed by some surgeons.1,3,11 From the mechanical standpoint, in comparison to compression screws, the buttress plate provides improved methods of internal fixation for a collapsed fracture. It is considered to be a perfect mechanical construct that meets the anatomic and biomechanical requirements of unstable fractures with the tendency of their fragments to collapse axially.12 The use of plates to treat the pseudarthrosis of the scaphoid has been described in the past. AO plates were described for the treatment of scaphoid pseudarthrosis by Braun et al.13 The Ender compression hooked blade plate system was suggested by Huene and Huene14 and Stankovic´ and Burchhardt.15 The function of the Ender hook plate was described as fixing the main bone fragments and exerting pressure on the in-between lying bone transplant.14,15 Contrary to the concept of the Ender hook plate, the volar buttress plate was used in the present study to stabilize the reduced scaphoid fragments and to buttress the relevant compression or axial forces. This study was undertaken to report the results of 14 nonunited scaphoid waist fractures treated by reduction of the collapse deformity by anterior wedge graft and internal fixation with the use of 1.5- or 2.0-mm miniplates and screws on the volar side of the scaphoid. MATERIALS AND METHODS A review of 14 patients who underwent open reduction, anterior wedge-shaped bone grafting, and internal fixation by volar buttress plate for the treatment of scaphoid fracture nonunions between March 2005 and October 2008 was carried out. The criterion for inclusion was symptomatic nonunited scaphoid wrist fracture that had been present for longer than 6 months. None of the patients had undergone previous scaphoid surgery. All of the patients were men, with an average age of 26 years (range, 20 –36 y). The right hand was involved in 9 patients (8 dominant; 1 nondominant) and the left hand in 5 patients (2 dominant; 3 nondominant). Ten patients were engaged in heavy manual work and 4 in office-type work. The average interval between injury and surgical treatment was 16.5 months (range, 7–96 mo). The mean period of follow-up was 11 months (range, 9 –19 mo). All fractures were the result of a fall on the outstretched hand. Preoperative planning on the basis of comparative radiographs of the opposite wrist was carried out.16 On the basis of plain radiographs and intraoperative findings, all scaphoid nonunions were classified according to the system of Alnot17 (Table 1). Six patients had
TABLE 1. Alnot’s Scaphoid Nonunion Classification Stage I
Linear pseudarthrosis
Stage II IIA
Slight bone resorption, no displacement
IIB
Unstable pseudarthrosis, palmar flexion and adaptive DISI, palmar bone loss
Stage III IIIA
Unstable pseudarthrosis, palmar bone loss, radioscaphoid arthritis
IIIB
Radiocarpal arthritis
FIGURE 1: Exposure of the fracture site through the standard Russe anterior approach.
nonunions classified as Alnot’s type IIA, 6 as Alnot’s IIB, and 1 as Alnot’s IIIA. Surgical technique General anesthesia was used in all patients; it was necessary when planning to harvest bone graft from the iliac crest. The patient was placed in the supine position. An inflated upper arm tourniquet was applied to the surgical extremity. All patients underwent surgery through the standard Russe anterior approach (Fig. 1). The capsule
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FIGURE 2: The fracture site is excised with curette to viable bleeding bone.
of the wrist joint was incised longitudinally to expose the palmar surface of the scaphoid. The exposure was extended distally to the level of the scaphotrapezial joint, but the scaphotrapezial joint was not opened. With the scaphoid exposed, the irregular borders of the nonunion site were resected with the use of a small chisel or a curette, down to a viable bleeding bone (Fig. 2). The scaphoid was reduced, according to the method of Mathoulin and Brunelli,18 by applying axial traction to the thumb with maximal ulnar deviation and extension of the wrist. This step is easier if a rolled surgical towel is placed under the wrist, so that the operating assistant can simply pull on the thumb. While in traction, the exact size of the graft could be evaluated. A wedge-shaped corticocancellous graft was obtained from the iliac crest, shaped to fit the gap, and inserted into the volar defect (Fig. 3). The image intensifier was used to make sure that appropriate correction of the scaphoid deformity and the lunate rotation has been achieved after insertion of the bone graft. Internal fixation was then accomplished with the 1.5- or 2.0-mm miniplate. A plate of appropriate length (usually 4 –5 holes) was selected. The plate was bent to conform to the contour of the volar surface of the scaphoid. Two to four cortical AO miniscrews (1.5–2.0 mm in diameter) were then
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FIGURE 3: A wedge-shaped corticocancellous graft, shaped to fit the gap, is inserted into the volar defect.
FIGURE 4: Two to 4 cortical AO miniscrews (1.5–2.0 mm in diameter) are inserted.
inserted, first in the distal pole and then in the proximal pole (Fig. 4). A 1.5- to 2-mm (L-shaped or straight) titanium miniplate was considered suitable for this type of fixation. These plates are used commonly for maxillofacial surgery (Leibinger) or phalangeal and metacarpal fracture surgeries
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(modular hand system; Synthes). L-plates were used in 5 cases, and straight plates in 9 cases. Four screws were inserted (2 in the proximal pole and 2 in the distal pole) in 6 patients, 3 screws were inserted in 4 patients, and 2 screws were inserted in 4 patients. After internal fixation was completed, the radioscaphoid articulation was inspected. The joint mobility was checked to exclude plate impingement. Postoperative care Palmar and dorsal plaster splints, which included the thumb, were used for 2 weeks. After removal of the skin sutures, a short thumb spica cast was then applied. The average time of postoperative immobilization (with cast or brace) was 9.5 weeks (range, 8–12 wk) for the whole series. The period of immobilization was based on the radiographic assessment of bone union during the follow-up period. Radiographic assessment Patients were evaluated preoperatively and during follow-up. Assessment of the carpal alignment was carried out by tracings of the radiographic findings in the posteroanterior and lateral x-ray films of the injured and contralateral wrists.16 The radiolunate and scapholunate angles were measured with preoperative and postoperative radiographs. The uninjured opposite wrists served as the control for these measurements. Preoperative and postoperative radiographs were measured for associated DISI, as expressed by having scapholunate angle ⬎60°, or difference in the radiolunate angle ⬎10° between the affected and unaffected wrists.3,19 Eight patients had radiographic evidence of DISI. The criteria used to establish healing were (1) absence of pain; (2) radiographic evidence of bridging bony trabeculae across the graft with standard scaphoid views8; and (3) no signs of implant loosening. Clinical assessment The range of motion of the wrist was recorded with goniometer measurements in degrees from the neutral position into extension and flexion. The range of motion of the uninjured side was also recorded. Grip strength was measured and recorded as a percentage of the strength of the untreated hand at the same grip position. The strength measurement of the nondominant hand was multiplied by 1.07 before comparison with the grip strength of the dominant hand. Overall clinical results were graded on the wrist evaluation rating scale modified by Cooney et al.20 The clinical rating was given to each patient as follows:
pain, functional status, range of wrist motion, and grip strength measured as percentages of normal (range, 0 –25 points). Pain was considered mild if it occurred at the extremes of wrist motion but neither physically nor psychologically disturbed the patient; moderate if it physically or psychologically or both disturbed the patient during heavy manual labor, and severe if it occurred during activities of daily living and at rest. Points were accumulated for the 4 categories. A score of ⱖ90 was rated excellent, 80 – 89 was good, 65–79 was fair, and ⬍65 was poor. The radiographic appearance was not included in the point score. Statistical methods The primary analysis outcome was the rate of successful fracture union among the 14 patients in the study. Because patients had different durations of follow-up periods, this end point was analyzed as a time-to-event outcome. Preoperative and postoperative clinical and radiographic measures were analyzed with use of paired t-tests. All statistical tests were 2-sided, and p ⬍ .05 was considered statistically significant. RESULTS Successful bone union was obtained in 13 of 14 cases (93%) (Fig. 5). Union was achieved in a mean of 3.8 months (range, 3–7 mo). One fracture nonunion (case 9) failed to achieve union after 10 months of follow-up. The scaphoid had signs of avascular necrosis of the proximal fragment intraoperatively. A repeat cancellous bone-grafting procedure was then carried out, which also failed. The DISI was corrected in all cases and did not deteriorate with follow-up. Carpal alignment shown by radiolunate and scapholunate angles was improved after surgery (Table 2). On average, the mean of the radiolunate angle measured 7.57° (⫾SD 8.79) before surgery to 1.21°(⫾SD 3.72) after surgery, and the scapholunate angle measured 61.14° (⫾SD 8.51) before surgery to 47.28° (⫾SD 5.03) after surgery (Fig. 6). A statistically significant difference was observed between the preoperative and postoperative flexion-extension arc of wrist motion (p ⬍ .001) and between the preoperative and postoperative scapholunate angle (p ⬍ .05). No statistically significant difference was observed between the preoperative and postoperative radiolunate angle. The postoperative wrist score ranged from 55 to 95 points with an average of 78.93 points (⫾SD 11.63) (Table 2).
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FIGURE 5: Preoperative x-ray A and the same case 16 weeks after surgery B.
TABLE 2. Preoperative and Postoperative Clinical, Radiographic Findings, and Functional Score of Patients With Scaphoid Waist Nonunion Flexion-Extension Arc of Wrist Motion Patient No.
Alnot’s Type
1
IIA
2
IIA
3
IIIA
85
4
IIA
95
5
IIB
90
6
IIB
90
7
IIB
8
IIB
Pre
Radiolunate Angle Pre
Post
Scapholunate Angle
Opp
Pre
Post
Opp
DISI
Union Rate (ms)
Wrist Score
Post
Opp
100
105
140
0
0
0
50
50
45
—
3
95
95
110
130
⫺15
0
4
65
48
43
Yes
3
80
95
135
⫺22
0
0
62
42
40
Yes
7
85
105
130
5
0
0
55
50
40
—
3
90
100
135
⫺14
5
0
60
48
48
Yes
4
80
105
110
⫺10
⫺4
0
72
50
50
Yes
3
65
85
100
115
⫺12
⫺5
0
68
48
44
Yes
5
70
90
105
140
⫺8
0
0
65
45
42
—
4
80
9
IIIA
75
90
135
⫺15
⫺9
⫺5
70
60
48
Yes
—
55
10
IIA
100
105
125
7
⫺2
0
45
45
40
—
3
95
11
IIB
90
100
140
⫺10
⫺4
0
62
40
44
Yes
4
65
12
IIA
107
110
145
5
0
5
50
45
40
—
3
85
13
IIB
80
90
100
⫺12
⫺3
4
72
41
45
Yes
5
80
14
IIA
105
105
130
⫺5
5
0
60
50
42
—
3
80
101.7
129.2
⫺7.57
61.14
47.2
3.8
78.9
Average
91.9
⫺1.21
Pre, preoperative; post, postoperative; opp, opposite side.
The arc of flexion-extension improved from a mean of 92° preoperatively to 102° postoperatively. The postoperative range of motion regained 78.72% (⫾SD 0.08%) of the range of the opposite side.
Grip strength improved from 61% (range, 47%– 73%) preoperatively to 73% (range, 68%– 86%) of the grip strength of the contralateral hand postoperatively.
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FIGURE 6: Preoperative A and postoperative B radiolunate and scapholunate angles. The dotted lines indicate the radiolunate axes. The solid lines indicate the scapholunate axes.
At the latest follow-up, 8 patients were without pain, 4 patients had only mild pain, 2 had moderate pain, and none had severe pain. The patient whose fracture failed to unite had poor functional rating. He only experienced moderate pain. DISCUSSION Nakamura et al.3 have described that the volar type of scaphoid fractures collapses into a humpback deformity over time through erosion of the volar and radial cortices, creating a true defect compared with the normal dimensions of the scaphoid.4,21 The volar collapse can be corrected both radiographically and clinically by the insertion of a wedge-shaped bone graft of appropriate length into the shortened scaphoid. Reduction of the humpback deformity simultaneously corrects DISI deformity.3 The anterior wedge graft preserves correction of the humpback deformity and provides an adequate contact area for bony union. This is to be stabilized by internal fixation with the use of Herbert’s or AO/ASIF screws.6,16,22–24 Screw fixation The use of Herbert screw fixation in the management of scaphoid fractures is considered by many investigators
to be the treatment of choice.1,6,10,22,23,25–32 More recent reports have shown some technical difficulties of screw insertion.1,3,6,9,27,33 These technical difficulties are particularly addressed in cases of nonunited scaphoid wrist fractures that have palmar bone deficiency when screw insertion is by the palmar route.11,34 Buttress plate Muller et al.,12 in their text, Manual of Internal Fixation, stated that, “If the fracture is in the metaphysis and the cortical shell has been comminuted, the compressive forces tend to lead to an axial deviation or bending. Lag screw fixation cannot overcome these deforming forces of shear and bending. In order to prevent deformity, it is necessary to supplement the fixation with a supporting or a buttress plate. Thus the buttress plate must be applied to the area or cortex which has been broken and which is coming under load.” Reduction of DISI simultaneously corrects humpback deformity and yields a straighter scaphoid. In this mechanical situation, palmar buttress plating seems to be the most consistent biomechanical form of osteosynthesis for this particular type of fracture. Buttress plate counteracts the compression forces and axial bending that involve the proximal and distal poles of the scaph-
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oid. To achieve this function, accurate plate contouring is required. The buttress plate is fixed to the proximal and distal main fracture fragments for adequate fixation and support. The screws in the fragment that is being buttressed prevent any shift of the bone under the plate. This prevents any deformity under axial load.12 The number of screws will depend on the stability of the fracture after the wedge graft has been inserted and on the bone quality. Unused screw holes remaining in the middle of the plate are not deleterious to the implant construct. They distribute bending forces and allow slight movement in the fracture zone, which is a good stimulus for callus formation. Furthermore, an additional advantage of the middle segment of the plate is that it maintains the anterior wedge graft in position, preventing its extrusion. Cooney et al.6 reported several cases of anterior interpositional graft extrusion with a Herbert screw insertion, which suggests that adequate stability had not been achieved. Nakamura et al.3 recommended stabilization of the bone graft by a small impactor while the screw was being inserted, to maintain the position of the graft and to avoid its extrusion. In the present study, successful bone union was obtained in 13 of 14 patients. The case of nonunion that failed to unite (case 9) had exhibited intraoperative signs of avascularity in the proximal fragment. The union rate in the present study, at an average follow-up of 11 months, was 93%. Reported rates of union after bone grafting and Herbert screw fixation have varied from 71% to 95%.6,7,34 –38 Union was achieved in a mean of 3.8 months; this is comparable to the mean period of union of other reported series (3.4 mo).38 In the present study, carpal alignment shown by radiolunate and scapholunate angles was improved after surgery. The radiolunate angle was 87° before surgery and improved to 1° after surgery and the scapholunate angle from 61° to 47°, on average. Tsuyuguchi et al.38 reported improvement of the radiolunate angle from 5.5° before surgery to 0.1° after surgery and the scapholunate angle from 65° to 55°, on average. In the present series, patients regained 78% of the motion of the contralateral wrist and 73% of the strength of the contralateral hand. Eggli et al.35 reported 83.5% gain of postoperative range of motion and ⬎70% of the strength in reference to the opposite side. In this study the final outcome after an average follow-up of 11 months showed 71% excellent or good results, in agreement with the results of other reports.36,38 This series combined the traditional technique of reduction of the humpback deformity and insertion of
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anterior wedge graft with a different method of internal fixation with the use of a volar buttress plate for stabilization. The preliminary results are encouraging. However, further cadaveric, biomechanical, and clinical studies are needed for accurate evaluation of the efficiency of this technique in management of scaphoid wrist nonunion. REFERENCES 1. Fernandez DL. Anterior bone grafting and conventional lag screw fixation to treat scaphoid nonunion. J Hand Surg 1990;15A:140 – 147. 2. Henry M. Collapsed scaphoid non-union with dorsal intercalated segment instability and avascular necrosis treated by vascularised wedge-shaped bone graft and fixation. J Hand Surg 2007;32E:148 – 154. 3. Nakamura R, Horii E, Watanabe K, Tsunoda K, Miura T. Scaphoid non-union: factors affecting the functional outcome of open reduction and wedge grafting with Herbert screw fixation. J Hand Surg 1993;18B:219 –224. 4. Tomaino MM, King J, Pizillo M. Correction of lunate malalignment when bone grafting scaphoid non-union with humpback deformity: rationale and results of a technique revisited J Hand Surg 2000;25A: 322–329. 5. Barton NJ. Experience with scaphoid grafting. J Hand Surg 1997; 22B:153–160. 6. Cooney WP, Linscheid RL, Dobyns JH, Wood MB. Scaphoid nonunion: role of anterior interpositional bone grafts. J Hand Surg 1988;13A:635– 650. 7. Daly K, Gill P, Magnussen PA, Simoms RB. Established nonunion of the scaphoid treated by volar wedge grafting and Herbert screw fixation. J Bone Joint Surg 1996;78B:530 –534. 8. Filan SL, Herbert TJ. Herbert screw fixation of scaphoid fractures. J Bone Joint Surg 1996;78B:519 –529. 9. Radford PJ, Matthewson MH, Meggitt BF. The Herbert screw for delayed and non-union of scaphoid fractures: a review of fifty cases. J Hand Surg 1990;15B:455– 459. 10. Warren-Smith CD, Barton NJ. Non-union of the scaphoid: Russe graft vs Herbert screw. J Hand Surg 1988;13B:83– 86. 11. del Piñal F. Treatment of nonunion of the scaphoid by a limited combined approach. J Bone Joint Surg 2001;83B:78 – 82. 12. Muller ME, Allgower M, Schneider R, Willenegger H. Buttress plate. In: Allgower M. ed. Manual of internal fixation. Techniques recommended by the AO-ASIF. Berlin Heidelberg: Springer-Verlag, 1991;200:208 –210. 13. Braun C, Gross G, Bühren V. Osteosynthesis using a buttress plate—a new principle for stabilizing scaphoid pseudarthroses [in German] Unfallchirurg 1993;96:9 –11. 14. Huene DR, Huene DS. Treatment of nonunions of the scaphoid with the Ender compression blade plate system. J Hand Surg 1991;16A: 913–922. 15. Stankovic´ P, Burchhardt H. Experience with the Ender hooked plate in the management of 42 scaphoid pseudarthroses [in German]. Handchir Mikrochir Plast Chir 1993;25:217–222. 16. Fernandez DL. A technique for anterior wedge-shaped grafts for scaphoid nonunions with carpal instability. J Hand Surg 1984;9A: 733–737. 17. Alnot JY. Fractures and pseudarthroses of the carpal scaphoid. Type II, III and IV fractures of the median section. Diagnosis, therapeutic indications and assessment of the results [in French]. Rev Chir Orthop Reparatrice Appar Mot 988;74:700 –702. 18. Mathoulin C, Brunelli F. Further experience with the index metacarpal vascularized bone graft. J Hand Surg 1998;23B:311–317.
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19. Abe Y, Doi K, Hattori Y. The clinical significance of the scaphoid cortical ring sign: a study of normal wrist x-rays. J Hand Surg 2008;33E:126 –129. 20. Cooney WP, Bussey R, Dobyns JH, Linscheid RL. Difficult wrist fractures: perilunate fracture-dislocations of the wrist. Clin Orthop Relat Res 1987;214:136 –147. 21. Oka K, Murase T, Moritomo H. Patterns of bone defect in scaphoid non-union: a 3-dimensional and quantitative analysis. J Hand Surg 2005;30A:359 –365. 22. Merrell GA, Wolfe SW, Sladc JF III. Treatment of scaphoid nonunions: quantitative meta-analysis of the literature. J Hand Surg 2002;27A:685– 691. 23. Nakamura R, Hori M, Horii E, Miura T. Reduction of the scaphoid fracture with DISI alignment. J Hand Surg 1987;12A:1000 –1005. 24. Nakamura R, Imaeda T, Tsuge S, Watanabe K. Scaphoid non-union with DISI deformity: a survey of clinical cases with special reference to ligamentous injury. J Hand Surg 1991;16B:156 –161. 25. Adams BD, Blair WF, Reagan DS, Grunberg AB. Technical factors related to Herbert screw fixation. J Hand Surg 1988;13A: 893– 899. 26. Bunker TD, MacNamee PB, Scott TD. The Herbert screw for scaphoid fractures. a multicentre study. J Bone Joint Surg 1987;69B:631– 634. 27. Ford DJ, Khoury G, El-Hadidi S, Lunn PG, Burke FD. The Herbert screw for fractures of the scaphoid. A review of results and technical difficulties. J Bone Joint Surg 1987;69B:124 –127. 28. Herbert TJ, Fisher WE. Management of the fractured scaphoid using a new bone screw. J Bone Joint Surg 1984;66B:114 –123.
29. Leyshon A, Ireland J, Trickey EL. The treatment of delayed union and non-union of the carpal scaphoid by screw fixation. J Bone Joint Surg 1984;66B:124 –127. 30. Manske PR, Mccarthy JA, Strecker WB. Use of the Herbert bone screw for scaphoid nonunions. Orthopedocs 1988;11:1653–1661. 31. Pring DJ, Hartley EB, Williams DJ. Scaphoid osteosynthesis: early experience with the Herbert bone screw. J Hand Surg 1987;12B:46 – 49. 32. Wozasek GE, Moser KD. Percutaneous screw fixation for fractures of the scaphoid. J Bone Joint Surg 1991;73B:138 –142. 33. Inoue G, Shionoya K, Kuwahata Y. Ununited proximal pole scaphoid fractures: treatment with a Herbert screw in 16 cases followed for 0.5– 8 years. Acta Orthop Scand 1997;68:124 –127. 34. Trumble TE, Clarke T, Kreder HJ. Non-union of the scaphoid: treatment with cannulated screws compared with treatment with Herbert screws. J Bone Joint Surg 1996;78A:1829 –1837. 35. Eggli S, Fernandez DL, Beck T. Unstable scaphoid fracture nonunion: a medium-term study of anterior wedge grafting procedures. J Hand Surg 2002;27B:36 – 41. 36. Inoue G, Shionoya K. Herbert screw fixation by limited access for acute fractures of the scaphoid. J Bone Joint Surg 1997;79B:418 – 421. 37. Shah J, Jones WA. Factors affecting the outcome in 50 cases of scaphoid nonunion treated with Herbert screw fixation. J Hand Surg 1998;23B:680 – 685. 38. Tsuyuguchi Y, Murase T, Hidaka N, Ohno H, Kawai H. Anterior wedge-shaped bone graft for old scaphoid fractures or non-unions: an analysis of relevant carpal alignment. J Hand Surg 1995;20B: 194 –200.
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