Abstract
Successful ORIF of proximal humeral fractures requires a careful assessment of the patient factors (age/osteoporosis/functional expectations), accurate identification the fracture segments (head/shaft/tuberosities) and accessory factors which are of vascular and surgical relevance (length of posteromedial metaphyseal head extension, integrity of medial soft tissue hinge, head split segments, tuberosity/head segments impacted to-gether or distracted apart).
Fixation of the fracture can be achieved by a number of techniques because of the multiple factors that often apply—numerous techniques are usually required of the surgeon.
The principles of fixation require accurate restoration of the head and tuberosity orientation, fixation of the metaphyseal segments (tuberosities) results in a stable circular platform on which the head segment rests. Thus, the fixation of choice acts as a load sharing device not a load bearing device. This fixation is often augmented with tension band and circlage suture fixation. These concepts are especially applicable to the osteoporotic patient.
The order of fixation requires that the medial hinge not be disrupted. If it is disrupted in the younger patient it requires fixation first. All tuberosity segments are tagged with ethibond sutures. The head and the largest tuberosity segment are reduced and held with k-wire or canulated scews, avoiding the central medullary canal entry point. If the head tuberosity segment is unstable in relation to the shaft, the fixation implant of choice (plate/intramedullary) is chosen and the head/tuberosity complex is reduced to the shaft. Depending on the fracture segments and the degree of comminution this may require compression of distraction.
Post-op the patient is immobilised in external rotation to balance the cuff forces. If very rigid fixation is achieved then early mobilisation is undertaken to minimise the adhesions due to opening of the subdeltoid space. If fixation is tenuous movement is commenced a 3–4 weeks.
AVN of the humeral head with good tuberosity head architecure can be salvaged. The diagnosis of AVN is determned at three months with a MRI and consideration given to Zolidronate therapy. Post-traumatic stiffness with good architecture can be salvaged with an arthroscopic capsular release.
