Treatment of midshaft clavicular delayed and non-unions with anteroinferior locking compression plating

Twenty patients (21 clavicles) were treated surgically for a midshaft delayed or non-union at the Academic Medical Center in Amsterdam from 2003 to 2007 by a single surgeon P. Kloen. We defined non-union as the lack of both periosteal and endosteal healing response, bridging the fracture after 6 months time. Delayed union was defined as lack of bridging callus between 3 and 6 months. In cases of doubt, a CT scan was performed to support or reject the diagnosis based on conventional radiographic images and clinical signs such as pain and weakness. Ten patients were female and ten were male. The mean age was 48.2 years (range 16–65). Initial fractures resulted all from trauma: 15 of them were falls in and around the house and during sports activities. Six non-unions were the result of a traffic accident, of which three motorcycle-related. The average duration of non-union before intervention in our clinic was 23 months (range 3–240). Clavicle fractures occurred in 13 (62%) cases on the right side, in all but one case the dominant limb. Eighteen non-unions were atrophic with minimal shortening, three were hypertrophic. Pain was present in all 20 patients. Subjective weakness of the affected limb was only seen in five, all others thought they had not lost any arm strength. We did not use a force measuring device. One patient presented with a chronic wound dehiscence, one with complaints of hampered swallowing, which we were not completely able to understand, and one with paraesthesias. There were no pathologic fractures although one patient had radiotherapy including the clavicular area for Hodgkin lymphoma in the distant past. Fourteen patients were not operated previously. Six patients were initially operated on elsewhere: four directly after trauma, one after 2 months because of lacking callus and persisting disabling pain. One patient underwent multiple operations elsewhere before she presented to us with an infected non-union. In her case, the treatment with anteroinferior LCP was preceded by debridement, antibiotics and temporary stabilization using a 3.5 mm standard LCP as an external fixation device for 4 weeks to allow the open wound to heal. All other patients were operated by us only once.

Under general anaesthesia, the patient was placed in a beach-chair position and draped allowing access to the clavicle and the ipsilateral iliac crest. No antibiotics were given until deep cultures were obtained. The incision was made just below the clavicle. In cases where a plate revision was performed, the incision was made over the scar and the skin pulled down to reach the anteroinferior side of the clavicle. A dissection was carried out carefully avoiding any injury to the subclavian vessels and the anterior fibres of the brachial plexus. When superior fibres of the pectoral muscle are abundant they can be cut and inserted under the plate later on. Locating the normal bone medial and lateral with regard to the non-union was generally easier allowing a ‘safe’ approach. After debridement of intervening tissue in the non-union with a knife or rongeur, both medullary canals were opened with a 2.0 mm drill. This was facilitated by holding the ends with a pointed reduction clamp. A 3.5 mm LCP was contoured to fit the serpentine shape of the anteroinferior clavicle optimally. The plate is first attached at the lateral side with at least one screw. In osteopenic bone, it might be prudent to use locking screws. The non-union was then reduced by pushing the lateral clavicle inward and upward. A small Verbrugge or bone reduction forceps can be applied around the plate and medial aspect. If possible a 3.5 mm cortical lag screw can be placed below the plate through the obliquity of the non-union. Fixation was then completed with additional screws medially and laterally. In most of our patients (67%) we used a 7-hole plate. Harvesting cancellous bone from the iliac crest was done using a standard technique. Alternatively a commercially available bone graft substitute could be used. Decortication was done with a small osteotome at both non-union ends before the bone graft was placed. Postoperatively, the patients were given a sling for 10 days to allow wound healing. Pendulum and Codman exercises were started directly on the postoperative day. Active assisted range of motion exercises up to 90° abduction and anteflexion were allowed in the first 6 weeks. Active unlimited motion exercises and strengthening were allowed when there was radiographic evidence of consolidation. Clinical and radiological assessment was performed generally at 6 weeks, 3 months, 6 months and 1 year (Fig. 1). For the purpose of this study, patients were invited to fill out a questionnaire at their latest follow-up or by mail: the authorized Dutch version of the DASH (Disabilities of the Arm, Shoulder and Hand). This score ranges from 0 to 100 points, where 0 points represent the best result. The mean follow-up time was 30 months (range 10–52 months).