Complications of Interlocking Intramedullary Nailing for the Humeral Shaft Fracture

Kang, Chung Nam; Kim, Jong Oh; Kim, Dong Wook; Koh, Young Do; Oh, Jong Keon; Ko, Sang Hun; Jeong, Seung Wook

Abstract

Several advantages of intramedullary nails over plates and external fixators have led to an anpansion of the surgical indications for humeral shaft tractures. But, various morbidities due to proximity of several important structures, such as rotator cuff and radial nerve, follwed the operation. We reviewed our experience with 23 cases of humeral shaft fractures that were treated by interlocking intramedullary nailing to evaluate the pitfalls and the complications of this technique. Fifteen men and 8 women were followed for average 19.5 months. Twenty one (91.3%) of them had midshaft fractures. According to AO/ASIF classification, type A was most common(60.9%), and followed by type B(26.1%) and type C(13.O%). Eighteen of them had associated injuries - 5 radial nerve palsies, 1 Volkmans ischemic contracture, and 14 had fracture of other sites. Indications for interlocking intramedullary nailing were unsatisfactory reduction after closed reduction, fracture of the ipsilateral upper extremity, segmental fractures, and multiple injuries. The operation was performed average 6.7 days after injury. The final results were evaluated with radiographs for quality of union and with physical examination for functional status of the shoulder. There were four cases of complication associated with increase morbidity. A post operative radial verve palsy, associated with the distal interlocking screw fixation was developed due to inappropriately short nail insertion. And in one case, fracture healing was delayed due to distraction of the fracture gap after nailing. In another case subacromial impingement was developed secondary to protruded nail tip because the length was thought be the common underlying causative factor. Finally there was a case of iatrogenic fracture at the site of distal interlocking screw fixation and it was thought to be a technical problem. The results gave us the conclusion that inappropriate nail length was the common underlying causative factor of the complications. Therefore in the interlocking IM nailing for the humeral shaft fractures, accurate measurment of nail length is one of the most cirtical factor for the good final result.