HYBRID EXTERNAL FIXATOR FOR THE TREATMENT OF UNICAMERAL BONE CYSTS WITH PATHOLOGICAL FRACTURE IN THE PROXIMAL HUMERUS

Objective: Unicameral bone cyst is a nonneoplasticbone lesion characterized by its tenacity and risk ofrecurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present study was to evaluate the results of hybrid external fixator for thetreatment of a unicameral bone cyst with a pathologicalfracture. Methods: Hybrid external fixator for thetreatment of a unicameral bone cyst was performed intwelve patients. These patients presented with a pathological fracture and were managed immediately with hybridexternal fixator, of whom four had been managedconservatively at other clinics before they were referred toour department. The cyst was located in the proximalhumerus in all patients. The mean age of the patients at the time of surgery was 8.7 years, and the mean duration offollow-up was 32.6 months. Radiographic evaluation wasperformed according to the criteria of Capanna et al., andthe cyst was classified as completely healed, healed withresidual radiolucency (osteolysis), recurred, or having noresponse. Results: The healing period ranged from three to eight months. Eight cysts healed completely, and threehealed with residual radiolucent areas visible onradiographs. There was recurrence of one cyst that hadhealed with residual radiolucency. All of the cysts in thepresent study responded to treatment. A modulation ofhybrid external fixator was necessary in three patients, asthe bars had become too short after bone growth or the pins had been loose. No major complications were observed.Conclusion: Hybrid external fixator provides earlystability, which allows early mobilization and thus obviates the need for a plaster cast. This method of treatment alsoallows for an early return to normal activity.

Treatment of Unicameral and Aneurysmal Bone Cysts by Minimally Invasive Percutaneous Injection of Grafton DBF Putty Using the Kyphon Cement Delivery System

Background: Simple Unicameral and Aneurysmal Bone Cysts are benign lesions that may heal spontaneously especially after fracture which may be the first symptom. However, often size increases causing pain, and complications of fractures can severely compromise the patient. Aim: The results in a series of cases treated minimally invasive using a new device for the application of allogenic bone material appear highly promising and shall be presented. Patients and Methods: Eight consecutive patients with symptomatic Unicameral Bone Cysts (UBC) were treated by percutaneous instillation of Grafton? DBF Putty (demineralised allogenic bone containing fibers) mixed with autologous bone marrow using the Kyphon? Cement Delivery System (Medtronic), which allows the injection of this high viscosity paste by controlled high pressure. Five patients with Aneurysmal Bone Cysts (ABC) were treated accordingly after inactivation by Aethoxysclerol 3% and lacking bone formation. Using this approach a high rate of bone regeneration was observed in these patients at 8 months to 5 years follow-up (f/u). Conclusion: The presented technique of a minimally invasive biologic treatment led to highly satisfying results using the Grafton? DBF Putty with its higher potential for bone regeneration than demineralized bone matrix not containing fibres (DBM).