Acute Shortening and Re-Lengthening (ASRL) in Infected Non-union of Tibia - Advantages Revisited

Abstract

Introduction: A gap non-union in various conditions has been treated successfully by the Ilizarov method. The gap can be filled up either by an acute shortening and re-lengthening (ASRL) procedure or by an internal bone transport (IBT). We compared the functional and clinical outcome of ASRL and IBT in gap non-unions of the infected tibia.

Material and methods: A retrospective study was conducted in our department from the data collected in the period between 1997 and 2010. There were 86 cases of infected non-union of the tibia, in patients of the age group 18 to 65 years, with a minimum two-year follow-up. Group A consisted of cases treated by ASRL (n=46), and Group B, of cases by IBT (n=40). The non-union following both open and closed fractures had been treated by plate osteosynthesis, intra-medullary nails and primary Ilizarov fixators. Radical debridement was done and fragments stabilised with ring fixators. The actual bone gap and limb length discrepancy were measured on the operating table after debridement. In ASRL acute docking was done for defects up to 3cm, and subacute docking for bigger gaps. Corticotomy was done once there was no infection and distraction started after a latency of seven days. Dynamisation was followed by the application of a patellar tendon bearing cast for one month after removal of the ring with the clinico-radiological union.

Results: The bone loss was 3 to 8cm (4.77±1.43) in Group A and 3 to 9cm (5.31± 1.28) in Group B after thorough debridement. Bony union, eradication of infection and primary soft- tissue healing was 100%, 85% and 78% in Group A and 95%, 60%, 36% in Group B respectively. Nonunion at docking site, equinus deformity, false aneurysm, interposition of soft-tissue, transient nerve palsies were seen only in cases treated by IBT.

Conclusion: IBT is an established method to manage gap non-union of the tibia. In our study, complications were significantly higher in cases where IBT was employed. We, therefore, recommend ASRL with an established protocol for better results in terms of significantly less lengthening index, eradication of infection, and primary soft tissue healing. ASRL is a useful method to bridge the bone gap by making soft tissue and bone reconstruction easier, eliminating the disadvantages of IBT.

Keywords: ASRL; Ilizarov; gap non-union; internal bone transport.

Fig. 1:

(a) Clinical picture of a patient treated with ASRL. (b) Post-op Radiograph showing docking site and corticotomy being done. (c) Clinical picture showing docking site with foot-frame. (d) Clinical picture during follow-up (e) Radiographs at follow-up showing regenerate and docking site union. (f) Radiographs after Ring removal and Cast immobilisation.

Fig. 2:

(a) A case of non-union following Type III B open fracture. (b) After debridement with a bone gap of 8cm. (c) One month post-op picture after ASRL showing wound healing by secondary intention. (d) At follow-up for ring removal.

Fig. 3:

(a) Radiograph during IBT of a case of infected non-union showing regenerate. (b) Final follow-up of the same case after ring removal. (c) Clinical picture at final follow-up showing ROM of knee joint. (d) Clinical picture at final follow-up showing ankle plantar flexion. (e) Clinical picture at final follow-up showing ankle dorsiflexion.

Fig. 4:

(a) Final follow-up radiograph of a case treated by IBT. (b) clinical picture before ring removal. (c) Clinical picture showing ROM of knee flexion. (d) clinical picture showing ROM of ankle plantar flexion. (e) Clinical picture showing ROM of ankle dorsiflexion.

Fig. 5:

(a) Pre-op clinical photo of a case of infected non-union tibia with LLD. (b) Magnified image showing infected part with sinuses. (c) Pre-op AP view radiograph showing infected non-union. (d) Pre-op lateral view radiograph showing infected non-union. (e) After radical debridement and corticotomy with massive bone gap. (f) Subsequent radiograph during bone transport showing regenerate bone. (g) Final follow-up AP view radiograph showing union and regenerate. (h) Final follow-up Lat view radiographs showing union and regenerate.

Fig. 6:

Trifocal osteosynthesis with 4cm regenerate at both side of docking.

Fig. 7:

Protocol for Acute Shortening and Re-lengthening.

Fig. 8:

Protocol for Internal Bone Transport.