Ulnar lengthening using a half-ring sulcated external fixator for ulnar longitudinal deficiency: a case report.

Ulnar longitudinal deficiency (ULD) is a rare condition of the upper limbs. Although radius lengthening for radial longitudinal deficiencies (RLD) was found to be successful, no ulnar lengthening for ULD without RLD and hand deformities has been reported. Herein, we present a Bayne type II ULD case report of the ulnar lengthening and gradual reduction of the dislocated radial head in an 11-year-old boy using a half-ring sulcated external fixator. For ulnar lengthening/radial longitudinal traction for radial head reduction, transverse osteotomy in mid ulna was performed and half-ring sulcated external fixator was used for ulnar distraction lengthening. Radial longitudinal traction and stabilization of external fixator were achieved by transverse pins through ulna and radius. Distraction (1 mm/day) began at 5th day and was completed at 95th postoperative day. External fixator was applied for 7 months. Successful ulnar lengthening (81 mm; 62% gain) was achieved 1-year after the surgery and the range of elbow motion at 2 years was >40°. Forearm rotation and wrist extension/flexion were also preserved with no complaints of pain. We concluded that ulnar distraction lengthening and gradual reduction of radial head could improve appearance of the arm and were of significant benefit to the patient.

[Treatment of complex bone nonunion with external skeletal fixation].

OBJECTIVES: To summarize the experience in the treatment of 112 cases of complex bone nonunion from 1982 to 1999 in our department and introduce the technique of external skeletal fixation. METHODS: The two fragment ends of all cases were fixed under pressure with half-ring sulcated external skeletal fixator. Those cases complicated by bone defect or limb shortening were operated on with epiphysiotomy to restore the length of the limb in the period of compressive fixation or after the occurrence of bone union according to the condition of complicated infection and the length of the limb shortened. RESULTS: The nonunion of the 112 cases was united eventually. The infection in 34 cases was eradicated. Bone union in cases without infection took 3 approximately 7 months (average 5.2 months) and in cases with infection took 5 approximately 11 months (average 5.5 months). The length of the limb in 11 cases with bone defect was restored in the same period of compressive external fixation and another 8 cases achieved after bone union. The length between the injured and healthy limbs was balanced. CONCLUSIONS: When external skeletal fixation is employed to treat those troublesome cases of bone nonunion, the pins for fixation are inserted in sites far from the lesions and the non-united fragment ends are exposed only in the area without scars. Consequently, there is little interference with the blood circulation and the osteogenic potency of the fragment ends. The sclerotic bone tissue is not excised, the marrow cavity is not chased to be open and the fragment ends are only moderately modified. As a result, the stability of fixation is increased and further shortening of the limb avoided. External skeletal fixation using small pins with cross penetration results in plastic fixation and promotes bone healing. Bone lengthening with epiphysiotomy can restore the balance of the limbs.