Role of autologous non-vascularised intramedullary fibular strut graft in humeral shaft nonunions following failed plating

Abstract

Background: Non-union humeral shaft fractures are seen frequently in clinical practice at about 2-10% in conservative management and 30% in surgically operated patients. Osteosynthesis using dynamic compression plate (DCP), intramedullary nailing, locking compression plate (LCP), Ilizarov technique along with bone grafting have been reported previously. In cases of prior failed plate-screw osteosynthesis the resultant osteopenia, cortical defect, bone loss, scalloping around screws and metallosis, make the management of non-union more complicated. Fibular graft as an intramedullary strut is useful in these conditions by increasing screw purchase, union and mechanical stability. This study is a retrospective and prospective follow up of revision plating along with autologous non-vascularised intramedullary fibular strut graft (ANVFG) for humeral non-unions following failed plate osteosynthesis.

Materials and methods: Seventy eight cases of nonunion humeral shaft fractures were managed in our institute between 2008 and 2015. Of these, 57 cases were failed plate osteosynthesis, in which 15 cases were infected and 42 cases were noninfected. Out of the 78 cases, bone grafting was done in 55 cases. Fibular strut graft was used in 22 patients, of which 4 cases were of primary nonunion with osteoporotic bone. Applying the exclusion criteria of infection and inclusion criteria of failed plate osteosynthesis managed with revision plating using either LCP or DCP and ANVFG, 17 cases were studied. The mean age of the patients was 40.11 yrs (range: 26-57 yrs). The mean duration of non-union was 4.43 yrs (range: 0.5-14 yrs). The mean follow-up period was 33.41 months (range: 12-94 months). The average length of fibula was 10.7 cm (range: 6-15 cm). Main outcome measurements included bony union by radiographic assessment and pre- and postoperative functional evaluation using the DASH (Disabilities of the Arm, Shoulder and Hand) score. Results: Sixteen out of 17 fractures united following revision plating and fibular strut grafting. Average time taken for union was 3.5 months (range: 3-5 months). Complications included one each of implant failure with bending, transient radial nerve palsy and transient ulnar nerve palsy. No case had infection, graft site morbidity or peroneal nerve palsy. Functional assessment by DASH score improved from 59.14 (range: 43.6-73.21) preoperatively to 23.39 (range: 8.03-34.2) postoperatively (p = 0.0003). Conclusion: The results of our study indicate that revision plating along with ANVFG is a reliable option in humeral diaphyseal non-unions with failed plate-screw osteosynthesis providing adequate screw purchase, mechanical stability and high chances of union with good functional outcome.

Keywords: Failed internal fixation; Fibular graft; Humeral shaft fracture; Nonunion humerus; Plate osteosynthesis.

Fig. 1

(a,b) A 48 yrs old male with 6 months duration of implant failure with non-union humerus distal third and AP, lateral radiograph suggestive of screw breakage implant loosening and comminuted type of non-union. (c) Treated with revision plating and ANVFG. (d) 94 months follow up suggestive of union. (e) With good functional outcome.

Fig. 2

(a,b) A 42 yrs male with 7 months duration of implant failure non-union distal third humerus. (c) Treated with revision plating and ANVFG. (d) 36 months follow up suggestive of union at fracture site. (e) With good functional outcome.

Fig. 3

(a,b) A 45 yrs old female with 6 months duration of implant failure non-union, and AP, lateral radiograph suggestive of comminuted type of non-union. (c) Treated with revision plating and ANVFG. (d) 7 months follow up suggestive of union. (e) With good functional outcome.

Fig. 4

(a,b) A 35 yrs old male with 10 yrs duration of implant failure non-union, and AP, lateral radiograph suggestive of screw breakage, atrophic type of non-union with sclerosis of fracture ends. (c) Treated with revision plating and ANVFG. (d) 10 months follow up radiograph suggestive of union. (e) With fair functional outcome.

Fig. 5

(a,b) A 27 yrs old with 8 months old implant failure non-union Lt humerus and AP, lateral radiograph suggestive of implant breakage. (c) Treated with revision plating and hemi-fibular graft. (d) 4 months follow up radiograph suggestive of implant failure with bending. (e) With fair functional outcome.

Fig. 6

(a,b) A 30 yrs old male patient with implant failure non-union Rt humerus and AP, lateral radiograph suggestive of implant breakage, sclerosis of fracture ends and atrophic type non-union. (c) Treated with revision plating and ANVFG. Arrow showing intraoperative iatrogenic distal third fracture during implant retrieval. (d) 12 months follow up radiograph suggestive of union at fracture site and iatrogenic fracture site. (e) With good functional outcome.

Fig. 7

The functional assessment by DASH score in pre-operative and at final follow up. (* P= 0.0003)