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joint. Once this dissection is complete, Hohmann-type retractors can be used to aid in exposure. The surgeon must be mindful of the important volar neurovascular structures as well as the posterior interosseous nerve.

The osteotomy is then performed around the previously placed Steinmann pin (Fig. 81—2B). The site for the cut is chosen with fluoroscopic guidance such that it is within the mass, distal to the elbow joint, and perpendicular to the longitudinal axis of the ulna. The sagittal saw is used to carefully incise the bone, saving the volar cortex. An osteotome is then used to cut the remaining volar cortex.

The forearm is now supinated to the desired position, usually ~20 degrees of pronation. We cannot overemphasize that every child should be treated individually in choosing the degree of rotation to set the forearm in. The osteotomy is then secured with a crossed smooth C or K wire starting proximal and dorsal, and exiting the cortex opposite the osteotomy distal and volar (Fig. 81—2C).

Prior to closure, we perform fasciotomies of the extensor and flexor masses. Subcutaneous flaps are created over the extensor and flexor masses, and the muscular fascia is longitudinally incised. We have not experienced compartment syndrome in our patients since adding this last step to the procedure.

Once completed, the tourniquet is deflated, the wounds are irrigated, and any bleeding is controlled. The two pins are bent at the skin and cut so that they can easily be removed in the office in ~6 weeks, once there is radiographic evidence of healing. The patient is placed in a bulky long-arm cast incorporating the wrist.

Postoperative Management

Our patients are admitted to observation status overnight with the arm elevated to monitor their neurovascular status and check for evidence of compartment syndrome. They are then discharged the following day. We typically schedule a follow-up visit within 2 weeks to examine the wound and the status of the arm. We keep the patients in a well-padded bulky long-arm cast for a minimum of 4 weeks (usually 6 weeks). Pins are removed in the office after there is radiographic evidence of union (Fig. 81—3). Patients are then allowed to resume normal activities on a progressive basis. The need for range-of-motion therapy is assessed only when patients have been allowed to return to their activities out of the cast.

Figure 81—3. Follow-up radiograph. There is evidence of bony consolidation 5 weeks after surgery.

Alternative Methods of Management

As previously stated, some patients do not require any operative intervention for their synostosis. We feel that the presence of a synostosis, in and of itself, is not an indication for surgery. However, when patients have a synostosis that prevents or limits their functional use of the extremity, we believe surgery is indicated. Our approach has been to perform a rotational osteotomy. Previous authors have described a variety of techniques to do this. Ours, as stated, is a modification of Green's original description. Green used pins and plaster to maintain the forearm rotation during healing. Other authors have approached rotational osteotomies through different means. Simmons et al describe a technique similar to Green's, but recommended a two-stage correction if the degree of correction was greater than 85 degrees to avoid neurovascular complications. Ogino and Hikino recommend a single-stage correction with shortening of the forearm to lessen the risk of compartment syndrome. Lin et al describe performing the osteotomy via drill osteoclasis with manual manipulation into the desired position. Seitz et al describe supinating the forearm and maintaining the position using an external fixator.

The alternative philosophical approach is to attempt to restore forearm rotation. Early reports included synostosis takedown with interposition of mechanical hinges, anconeus muscle, or Silastic material. Many of these had limited success due to recurrent stiffness from reformation of a synostosis. The best synostosis excision results were recently reported with the use of a free vascularized interposition fascial-fat graft into the space to prevent reossification. These authors reported a pronosupination arc of ~70 degrees at follow-up.

Complications

Postoperative complications of a rotational osteotomy include wound infection, pin tract infection, nonunion, malunion, neurovascular compromise, and compartment syndrome. We give prophylactic antibiotics pre- and perioperatively to minimize the risk of surgical infection. We also keep the pins sterilely covered until they are ready to be removed. Malunion can best be avoided at the time of surgery by ensuring that the appropriate degree of forearm rotation is provided. This requires careful attention to the position of the patient under the drapes, and the position of the shoulder at the time of the procedure. The transfixing K or C wire will stabilize the osteotomy and prevent the mobility between the fragments that could otherwise promote a malunion or nonunion. With regard to neurovascular status, careful dissection of the synostosis mass prior to osteotomy and gentle retraction should sufficiently protect the major neurovascular structures that cross the proximal forearm. In addition, our incision avoids major neurovascular structures. Finally, we believe that prophylactic fasciotomies and bulky long-arm casting along with overnight admission and arm elevation are sufficient to prevent the development of postoperative compartment syndrome. Our technique does not employ rigid internal or external fixation; therefore, should compartment syndrome develop, the forearm could simply be de-rotated via the longitudinal wire, which will prevent malangulation.

Suggested Readings

Cleary JE, Omer GE. Congenital proximal radio-ulnar synostosis: natural history and functional assessment. J Bone Joint Surg [Am] 1985;67A:539—545.

Green WT, Mital MA. Congenital radio-ulnar synostosis: surgical treatment. J Bone Joint Surg [Am] 1979;61A:738-743.

Kanaya F, Ibaraki K. Mobilization of a congenital proximal radioulnar synostosis with use of a free vascularized fascio-fat graft. J Bone Joint Surg [Am] 1998;80A: 1186-1192.

Lin HH, Strecker WB, Manske PR, Schoenecker PL, Seyer DM. A surgical technique of radioulnar osteoclasis to correct severe forearm rotation deformities. J Pediatr Orthop 1995;15:53-58.

Mital MA. Congenital radioulnar synostosis and congenital dislocation ofthe radial head. Orthop Clin North Am 1976;7:375-383.

Ogino T, Hikino K. Congenital radio-ulnar synostosis: compensatory rotation around the wrist and rotation osteotomy. J Hand Surg 1987;12B:173-178.

Sachar K, Akelman E, Erlich MG. Radioulnar synostosis. Hand Clin 1994;10: 399-404.

Seitz WH Jr, Gordon TL, Konsens RM. Pediatric update #11. Congenital radioulnar synostosis. A new technique for derotational osteotomy. Orthop Rev 1990;19:192-196.

Simmons BP, Southmayd WW, Riseborough EJ. Congenital radioulnar synostosis. J Hand Surg 1983;9:829-838.

Waters PM, Simmons BP. Congenital abnormalities: elbow region. In: Peimer CA, ed. Surgery of the Hand and Upper Extremity. New York: McGraw-Hill; 1995:2049-2073.

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