Background: The "palm tree-like wiring" introduced by Kapandji and its modifications for proximal humeral fractures should be given the generic name "retrograde intramedullary multiple pinning through the deltoid 'V'" (IMPV). IMPV is still preferable for treating valgus-impacted four-part fractures in which K-wires have the advantage of working as an internal fixation material as well as a tool in fracture reduction.
Methods: Three 2.4-mm K-wires formed into the desired shape are used as the intramedullary pins and a 3.0- to 3.2-mm upwardly angled hole for each wire is opened in the deltoid "V." After the tips of two wires are introduced into the lateral aspect of the head, the valgus deformity of the head is gradually corrected by alternately tapping the two wires under fluoroscopy. When the head and metaphysis are strongly compressed together, open reduction is attempted. If required, the tuberosity fragments are surgically reduced and stabilized. We performed IMPV on one C2.1 fracture and nine C2.2 fractures with 1 year or more follow-up.
Results: No nonunion was observed, but avascular head necrosis with collapse was observed in two C2.2 fractures, of which constant score ratios to the normal side were 55% and 64%, respectively. The constant score ratios of the other eight patients were 92% ± 8% (70-96%).
Conclusions: IMPV is considered to be a preferable reducing and stabilizing method for valgus-impacted four-part fractures regardless of patient age. Additionally beneficial is being able to use the intramedullary pins as a tool for bone fragment reduction.