1

artery. This pedicle is long enough to reach the scaph terior aspect of the radius based on the volar carpal

I

nspired by the work of Kuhlman et al,12 we describe a vascularized graft harvested from the an

ANATOMIC BASIS FOR VOLAR VASCULARIZEDFrom Institut de la Main, Paris, France. Address reprint requests to Christophe L. Mathoulin, MD, Institut dela Main, 6 Square Jouvenetmathoulin@wanadoo.fr

,75016, Paris, France. E-mail:

treating scaphoid nonunions by using this source ofvascularized bone. Other vascularized grafts from theradial and dorsal aspects of the wrist and hand havebeen described, with similarly encouraging results.4-11

In this review, we describe the technical aspects of thevascular supply to the palmar aspect of the radiusbased on cadaver dissections and report on our experience using a vascularized palmar graft in a series ofpatients with scaphoid nonunions.

onvascularized autogenous bone grafts combined with internal fixation have become theN preferred treatment for scaphoid nonunions

for many surgeons. In 1965 Judet and Roy-Camille1

suggested using a bone graft harvested from the palmar aspect of the radius with a vascular supply fromfibers of the pronator quadratus muscle. Braun2 andKawai and Yamamoto3 reported excellent results in

also review our series of 72 patients treated by this technique.

deformity compared with the use of dorsal distal radius vascularized grafts. We from the palmar cortex of the distal radius, providing easier access to the scaphoid humpback deformity can be corrected by harvesting a wedge of vascularized bone

can serve as a pedicle for vascularized grafts. Scaphoid nonunions with a solution and determined that the radial portion of the palmar carpal arterial arch the distal radius in 40 fresh cadavers that were injected with a colored latex

by various investigators. We examined the blood supply to the palmar surface of

The use of vascularized bone grafts to treat scaphoid nonunion has been proposed

BY CHRISTOPHE L. MATHOULIN, MD

TECHNIQUE: VASCULARIZED BONE GRAFTS FROM THE VOLAR

DISTAL RADIUS TO TREAT SCAPHOID NONUNION

FIGURE 3. Magnified cadaver dissection showing the anastomosis zone forming the vascular “T”. Red, volar carpalartery; yellow, distal branch of the anterior interosseous artery; blue, branch of the ulnar artery.

oid without excessive tension (Fig 1). An arterialnetwork located on the palmar aspect of the distalradius and ulna perfuses the graft. In 40 cadaverdissections, we were able to confirm the presence of a volar carpal artery. This vessel originates from theradial artery at the level of the radial styloid and runsalong the palmar aspect of the radius (Fig 2). Theartery follows the distal edge of the pronator quadratus and forms a “T”-shaped anastomosis with theanterior interosseous artery adjacent the distal radioulnar joint (Fig 3). After branching from the radialartery, the volar carpal artery travels along the radialthird of the distal radius and penetrates the radius atthe radial epiphysis.

FIGURE 1. Cadaver dissection showing the volar carpal artery running along the distal edge of the pronator quadratusbefore anastomosing with the anterior interosseous arteryand a branch of the ulnar artery. Abbreviations: R, radialartery; U, ulnar artery.

FIGURE 2. Magnified cadaver dissection showing the originof the volar carpal artery, the lateral part of which is detachedfrom the radius.

MATHOULIN VASCULARIZED BONE GRAFTS 2

FIGURE 7. Diagram showing subperiosteal dissection of thelateral part of the pedicle.

FIGURE 5. Diagram showing the location of the flexor carpiradialis tendon and radial artery.

.

Harvesting Vascularized Bone Dissection of small arteries may result in damage to

the vessel unless it is harvested with a cuff of adjacenttissue. The volar carpal artery has a predictable location between the periosteum of the radius and distalmargin of the pronator quadratus. The fascia andmuscle of the pronator quadratus are incised 1 cmfrom its distal margin along the full width of themuscle. The periosteum is incised along the distal andproximal margins of this 1-cm strip of fascia andmuscle. The radial half of this strip is elevated, with

he scaphoid and radius are exposed in the intervalT between the radial artery and the tendon of theflexor carpi radialis (Figs 4, 5, and 6). With the wristin extension and ulnar deviation, the anterior capsuleis reflected, exposing the scaphoid and distal marginof the radius. Fibrous tissue and devascularized boneare removed from the site of the nonunion using asmall curved curette. Restoring the scaphoid to itsappropriate length is facilitated by traction on thethumb and by using a narrow osteotome to separatethe 2 poles of the scaphoid at the nonunion site.Intraoperative radiographs can help confirm the adequacy of the reduction. The dimensions of the defectin the scaphoid are measured while the osteotomemaintains separation of the fracture fragments. If nec

essary, the provisional reduction can be maintained byplacing a pin through the distal pole of the scaphoidinto the capitate and a second pin through the proximal pole into the lunate.

TECHNIQUE

FIGURE 6. With wrist flexion and retraction of the flexor carpiradialis and flexor pollicus longus tendons, the volar carpalartery often can be located running along the distal edge of the pronator quadratus.

FIGURE 4. Diagram showing the anterior surgical approachwith a medial palmar extension.

VASCULARIZED BONE GRAFTS MATHOULIN 3

FIGURE 9. Reduction and screw fixation of the scaphoid.Note the palmar bone loss (A). XXXXXXXXXXX (B).

FIGURE 10. (A, B) The graft fills the palmar defect withoutexcessive tension on the pedicle (A). XXXXXXX (B).

(A).osteotomesFIGURE 8. Harvesting the graft using

XXXXXXXXXXXXXXXXXXXXXXXX (B).

5-mm osteotomes (Fig 8). The graft and its pediclethen are dissected to the origin of the volar carpalartery. The most lateral attachments of the pronatorquadratus fascia can be divided without hesitation tocreate a 4- to 5-cm pedicle.

The scaphoid is stabilized with a screw insertedanteriorly and directed distal to proximal. The screw

its periosteum off the palmar cortex of the radius, byusing a combination of scalpel and osteotome (Fig 7).Dimensions of the graft are marked on the radius, andthe graft is harvested using 10-mm osteotomes. Theaxes of the osteotome are oblique on the distal andproximal part of the graft to create a pyramid-shapedgraft. The pedicle and bone are elevated using two

FIGURE 11. Anteroposterior radiograph of a stage IIA (Alnot) pseudarthrosis of the scaphoid. Note the extensive bone loss (A). Perioperative view showing the harvested bone graft and extensive palmar bone loss (B). Perioperative view showing thevascularized bone graft filling the defect. Note the absence of tension on the pedicle despite the extended position of the wrist (C). Radiograph showing union at 45 days. The graft has been well integrated (D). Tomography at 3 months after removal ofa painful screw. The hole left by the passage of the screw can be seen within the reconstructed scaphoid (E). Anteroposteriorradiograph of the same scaphoid 2 years after reconstruction by vascularized bone grafting (F).

5MATHOULINVASCULARIZED BONE GRAFTS

filled with cancellous bone from the distal radius. Thegraft can be stabilized by tightening the screw or witha pin inserted from the distal tubercle into the graft.This pin should be parallel to the screw to avoiddamaging the vascular pedicle (Fig 10).

The capsule, particularly the radioscaphocapitiateligament, is repaired with care to avoid compressing

is inserted as dorsal as possible to minimize interferingwith placement of the graft. We also avoid the scaphotrapezial joint to avoid future discomfort (Fig 9).

The bone graft is placed to fill the defect on thepalmar aspect of the scaphoid. If the surgeon is successful in matching the graft to the defect, no additional graft is necessary. Small residual defects can be

FIGURE 12. Anteroposterior radiograph of a stage IIB (Alnot)pseudarthrosis of the scaphoid. Note the bone loss withdisplacement at this stage (A). Radiograph showing union at45 days (B). Magnetic resonance image at 1 year. The scaphoid appears of normal contour (C).

MATHOULIN VASCULARIZED BONE GRAFTS 6

VASCULARIZED BONE GRAFTS MATHOULIN 7

the pedicle. The skin is closed over a suction drain.The wrist is immobilized in a palmar short-arm splintwith the wrist in about 40° of extension. If a pin is used to stabilize the graft, it is removed in 3 weeks. Wrist immobilization is continued until there is radiographic and clinical evidence of union.

days, based on the radiographic appearance. Representative cases are illustrated in Figs 11 and 12.

CONCLUSION

natomic dissections and our clinical experienceAhave shown the utility of vascularized bonegrafts based on the volar carpal artery to treat scaphoidnonunions. Graft harvested from the palmar aspect ofthe radius facilitates correction of the humpback deformity that frequently is seen in scaphoid nonunion.Although this technique was described initially forpersistent nonunion after surgical treatment, the rateof union and ultimate wrist function compels us topropose palmar vascularized bone grafts as a primarytreatment for scaphoid nonunion.

OUR EXPERIENCE

e used a volar vascularized bone graft in a seriesW of 72 patients presenting with scaphoid nonunions and a significant humpback deformity, whichwe believed would be difficult to treat using vascularized bone grafts from the dorsal distal radius because of pedicle length. Average time to union was 60

REFERENCES

the first dorsal metacarpal artery. J Hand Surg 1997;22B:425-427.Mathoulin C, Haerle M. Vascularized bone graft from thepalmar carpal artery for treatment of scaphoid nonunion.J Hand Surg 1998;23:318-323. Mathoulin C, Brunelli F. Further experience with the indexmetacarpal vascularized bone graft. J Hand Surg 1998;23B:311-317.Mathoulin C, Gilbert A. Vascularized bone transplants inupper limbs. In: Tubiana R, ed. Surgery of the skin andskeleton of the hand. London: Dunitz, 2001:93-106.Shin AY, Bishop AT. Vascularized bone grafts for scaphoidnonunions and Kienbock’s disease. Orthop Clin North Am2001;32:263-277.Kuhlman JN, Mimoun M, Boabighi A, Baux S. Vascularizedbone graft pedicled on the volar carpal artery for nonunion ofthe scaphoid. J Hand Surg 1987;12B:203-210. Haerle M, Schaller HE, Mathoulin C. Vascular anatomy ofthe palmar surfaces of the distal radius and ulna: its relevanceto pedicled bone grafts at the distal palmar forearm. J HandSurg 2003;28B:131-136.

1. Judet R, Rot-Camille R. Fractures et pseudarthroses duscaphoïde carpien. Utilisation d’un greffon vascularisé. Ac

´ de Chirurgie Orthopédique 1965;4:196-214.Braun RM. Viable pedicle bone grafting in the wrist. In:Urbaniak JR, ed. Microsurgery for major limb reconstruction,St. Louis, MO: Mosby, 1987:220-229. Kawai H, Yamamoto K. Pronator quadratus pedicled bonegraft for old scaphoid fractures. J Bone Joint Surg Br 1998;70:829-831. Brunelli F, Mathoulin C, Saffar P. [Description of a vascularized bone graft taken from the head of the second metacarpalbone]. Ann Chir Main 1992;11:40-45. Zaidemberg C, Siebert JW, Angrigiani. A new vascularizedbone graft for scaphoid nonunion. J Hand Surg 1991; 16A: Sheetz KK, Bishop AT, Berger RA. The arterial blood supplyof the distal radius and ulna and its potential use in vascularized pedicled bone grafts. J Hand Surg 1995;20A:902914. Yuceturk A, Isikar ZU, Tuncay C, Tandogan R. Treatment ofscaphoid nonunions with a vascularized bone graft based on

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