UNREAMED NAILING OF TIBIA SHAFT FRACTURES - UPDATE OF TECHNIQUE AND RESULTS BASED ON THE ANALYSIS OF 75 REVIEWED CASES

Nailing technique has changed in recent years in some important aspect s which are not limited to the omitted reaming procedure. These change s concern patient positioning, reduction technique, the use of tempora ry stabilizers such as the 'Pinless', and determination of implant len gth and diameter. Approach and exposure techniques have been modified to new, less invasive procedures, in order to fulfill technical, funct ional and aesthetic requirements. Techniques and tricks have been deve loped for avoidance of fragment diastasis and axial and torsional mala lignment. Finally, simple algorithms are described for the management of large bone defects, bilateral tibia shaft or ipsilateral femoral sh aft fractures, number and location of locking bolts, the 'when and how ' of patient mobilization and load bearing, and primary and secondary dynamization. These algorithms, techniques and procedures were develop ed in a series of 152 tibia shafts, which were stabilized with the AO unreamed tibia nail (UTN) in a prospective study between March 1989 an d June 1994. Of these, 75 cases with a mean follow-up of 19.4 +/- 6.3 (range 11 - 37) months after trauma were reviewed. Fractures were clas sified according to Muller (1990): 14 type A, 37 type B and 24 type C. Closed soft tissue damage was categorized according to our classifica tion: C0/1, n = 5; C2, n = 12; C3, n = 9 (Tscherne 1982). Among 49 ope n fractures 8 were OI, 18 OII, 10 OIIIA and 13 OIIIB (Gustilo 1976). T he main minor intraoperative complication was drill bit breakage (n = 10), most frequently at the proximal locking holes. The main postopera tive complication was breakage of locking bolts (n = 16), mainly betwe en weeks 6 and 20. Minor secondary reinterventions were, in most cases , secondary dynamization under local anaesthesia. Major reintervention were: soft tissue reconstructions (n = 5), isolated cancellous bone g raft (n = 6), and change of treatment (n = 12). There were nine change s to a reamed nail, two changes, in very proximal fractures, to plate osteosyntheses. There were three deep infections. Mean time to union w as 23.9 weeks (range 10-48 weeks, n = 73); in two cases non-union was observed. The overall result was judged with the Karlstrom-Olerud scor e, which was applicable in 66 of 75 cases; excellent, n = 2; good, n = 22; satisfactory, n = 24; fair, n = 9; poor, n = 9. In the remaining nine cases no scoring was attempted because of severe injuries around the knee or ankle.