Ashok Gavaskar, MS | Parthasarathy Srinivasan | Prakash Ayyadurai, MS (ORTH) | Bejoy George, DDS, DMD, DMed | Abraham Antony, MSc, MS (ORTH), MBBS | Jotheesvar K.N., MS (ORTH)

Subchondral bone impaction at the level of the radial neck, usually present at the anterior or lateral quadrant can be an associated feature in radial head fractures. Buttress plating principles suggest that subchondral zones of impaction are best supported by an implant positioned directly on the site of impaction to resist secondary collapse. The anatomical considerations limit the conventional radial head plating technique to a narrow safe zone in order So, irrespective of the zone of impaction the conventional plating zone remains the same, which may not provide the best possible mechanical construct for radial head fractures where the zone of impaction lies outside the safe zone for plating. Here, the authors present an alternate subchondral shelf plating technique performed through the zone of impaction.

Surgical technique:

The impacted head segment is elevated and the depth for insertion of the shelf plate is measured using a depth gauge. A 5 or 6 holed 2.4 mm locking compression plate from the mini fragment hand set is used to prepare the shelf plate. The plate is bent approximately at a 85° - 90° angle at the measured point indicated by the depth measurement. The bend is usually at the 3rd hole leaving 2 screw hole length (approximately 12 mm) to support the disimpacted radial head and 2 to 3 holes on the shaft to achieve stable fixation at the metaphysis

The bent plate is then inserted under the radial head through the cortical breach at the zone of impaction. The 90° bent plate usually sits slightly under contoured on the anterior aspect of the proximal radial metaphysis. So, a cortex screw inserted through the first plate hole at the metaphysis helps in tensioning the construct resulting in a stable support to the elevated radial head fragment. One or two more screws at the shaft are used to complete fixation of the shelf plate.

The shelf plate remains extra-articular, recessed below the radial head and the proximal radio-ulnar joint with scope for impingement free fixation along the entire circumference of the radial head.

Additional fixation as per our treatment protocol, is added in the form of tripod screws for (OTA - 2R1A2 fractures) or conventional plating using a contoured 2 mm T locked compression plate respecting the safe zone to avoid proximal radioulnar impingement in (OTA - 2R1C1 fractures).