Percutaneous treatment of lytic bone lesions

While the treatment of bony lesions, fracture non-unions, and bone segmental defects using operative dissection, exposure, and grafting is a well-established technique, a number of reports describe a technique for bone grafting using the percutaneous injection of bone marrow.

Fracture nonunions and delayed unions have been particularly amenable to percutaneous bone marrow injection. Healey and co-workers treated an oncogenic population which had undergone sarcoma resection followed by standard open bone grafting . Of eight patients, five had received chemotherapy and one had received radiotherapy. All eight received an injection of autogenous bone marrow to the sites. Seven demonstrated bone formation and five achieved bony union. Connolly described the healing of various tibial nonunions using percutaneously applied bone marrow; he noted that bone union occurred as quickly as would be expected with an open technique . Complications were limited to a 2-day duration of discomfort in the donor site in most patients and a likely contusion of the posterior tibial nerve leading to transient dysesthesias in one patient. Most recently, Garg and co-workers demonstrated the healing of humerus, ulnar, and tibial fracture nonunions in seventeen of twenty treated patients . Five of the patients were not good candidates for an open procedure because they had poor skin quality; the use of the percutaneous technique was perceived to be of great advantage.

Lytic bone lesions have also been managed percutaneously . In their preliminary report, Lokiec and co-workers identified simple active bone cysts of the proximal humerus, proximal tibia, and proximal femur in ten children. Three of the patients had been referred after failing other therapies, including open bone grafting or percutaneous steroid injections into the lesion. All patients were treated by these surgeons using a purely percutaneous technique. The cyst was localized intraoperatively with an image intensifier. They then percutaneously aspirated the cyst and simultaneously percutaneously aspirated autogenous bone marrow grafting material from the iliac crest. The harvested bone marrow was then injected directly into the newly cleared bone cysts through the same percutaneous access site. Follow-up evaluation, including clinical observation and radiographic studies, ranged from 12 to 48 months post-operatively. All ten cysts had consolidated within three months; within six months, all demonstrated narrowing, disappearance of the expansile pattern, and thickening of the cortex. No cyst increased in size after the first injection, and all healed completely within 6 to 12 months.

Wientroub and his co-workers have extended this procedure towards the treatment of children with fibrous dysplasia (personal communication). They have treated 9 patients with lytic lesions of the long bones by 1) aspirating the contents of the lesions percutaneously, 2) simultaneously harvesting normal bone marrow from the unaffected iliac crest, 3) mixing the marrow with the collagen component of Collagraft , and 4) percutaneously injecting the collagen/marrow component into the now empty space in the affected bone. They have noted healing of the lesions through radiographic follow-up and the absence of new fractures. No patients have suffered graft rejection or evidence of an allergic reaction to the bovine component of the Collagraft .

These reports have demonstrated the efficacy of selective reinjection of lesions. Healey and co-workers re-injected lesions in 5 patients when no healing was observed on serial radiographs . Of these, 2 progressed to healing during the course of the study.