Table 4 Detailed list of categorised definitions for bone/fracture and implant/surgery complications located at the distal radius

(Secondary) Loss of reduction

= secondary fragment dislocation

= redisplacement

= loss of radial/ulnar length

= dorsal angle change

= dorsal or palmar shortening

Any change in intra-/extraarticular angles, radial/ulnar length or secondary fragment dislocation compared to the immediate postoperative measurements

Malunion

Healed fracture in deformity (e.g. varus/valgus, rotational malunion) as a consequence of loss of reduction

Malunion

= residual extraarticular deformity

= residual articular gap/step-off

Inadequate/insufficient anatomical reduction as a consequence of significant change of the postoperative position. Bone unites in abnormal position and/or alignment

Fracture impaction

Articular impaction of ≥ 1 mm

Delayed healing

Insufficient signs of healing (> 3 months)

Nonunion

Indiscernible signs of healing (> 6 months)

Refracture

= secondary fracture

Fracture occurs at the same radial site with a load level otherwise tolerated by normal bone after the bone has solidly bridged

Functional deficit

As assessed with the functional scores of DASH, PRWE, ROM and grip strength

Implant/surgery

Primary malpositioning of plate

Failure to fix each fragment and/or failure to implant plate according to technical guide [17] (including anatomical reduction and plate positioning) during operation

Primary malpositioning of screw

Screws placed into the radiocarpal or radioulnar joint as seen on oblique X-rays or incorrect screw size chosen during operation

Secondary screw perforation

= secondary screw loosening

= screw back-out

Screws displaced into the radiocarpal or radioulnar joint as seen on oblique X-rays or incorrect screw size chosen (no initial perforation)

Implant (plate and screw) loosening

Multiple proximal or distal screw loosening leading to firstly, relative movement between one main fragment and the plate and secondly, pull-out of the implant

Plate/screw failure/breakage

Plate/screw breakage

Radiolucency around screw

Appearance of screw on X-ray without screw loosening