Proximal humerus fracture and acromioclavicular joint dislocation

Abstract

Proximal humerus fractures and injuries to the acromioclavicular joint are among the most common traumatic diseases of the upper extremity. Fractures of the proximal humerus occur most frequently in older people and are an indicator fracture of osteoporosis. While a large proportion of only slightly displaced fractures can be treated non-operatively, more complex fractures require surgical treatment. The choice of optimal treatment and the decision between joint-preserving surgery by means of osteosynthesis or endoprosthetic treatment is often a difficult decision in which both fracture morphology factors and individual factors should be taken into account. If endoprosthetic treatment is indicated, satisfactory long-term functional and clinical results have been achieved with a reverse shoulder arthroplasty. Injuries to the acromioclavicular joint occur primarily in young, athletic individuals. The common classification according to Rockwood divides the injury into 6 degrees of severity depending on the dislocation. This classification forms the basis for the decision on non-operative or surgical treatment. The indication for surgical treatment for higher-grade injuries is the subject of controversial debate in the latest literature. In chronic injuries, an autologous tendon transplant is also performed. Whereas in the past, treatment was often carried out using a hook plate, which was associated with complications, the gold standard today is minimally invasive treatment using Endobutton systems. This review provides an overview of the two injury patterns and discusses the various treatment options.

Keywords: acromioclavicular joint instability; arthroscopic assisted Endobutton systems; horizontal instability; joint-preserving locking plate fixation; proximal humerus fracture; reverse total shoulder arthroplasty.

Figure 1:

Female patient (53 y), right shoulder, valgus impacted, dislocated 3-part proximal humerus fracture (preoperative X-ray and (3D-) CT-scan: a – a.p., b – 3D-CT-reconstruction, c – sagittal, d – coronal), open reduction and internal fixation with a locking plate osteosynthesis (postoperative X-ray: e – a.p., f – Y-plane).

Figure 2:

Male patient (53 y), right shoulder, valgus impacted 4-part proximal humerus fracture (preoperative (3D-) CT-scan: a – 3D-CT-reconstruction, b – axial, c – coronal), open reduction and internal fixation with a laterally positioned locking plate osteosynthesis and a second, supportive, ventrally positioned plate to stabilize the lesser tuberosity (postoperative X-ray: d – a.p., e − Y-plane), complete removal of the double plate osteosynthesis and arthroscopically assisted arthrolysis (postoperative X-ray: f – a.p.).

Figure 3:

Female patient (83 y), right shoulder, varus distracted 4-part proximal humerus fracture (preoperative X-ray and (3D-) CT-scan: a – a.p., b – axial, c – sagittal, d – 3D-CT-reconstruction, e – coronal), implantation of a reverse total shoulder arthroplasty (postoperative X-ray: f – a.p.).

Figure 4:

Female patient (50 y), left shoulder, acute acromioclavicular joint dislocation (Rockwood 5) (preoperative X-ray): a – Zanca stress radiographs with 10 kg weights left shoulder, b – Zanca stress radiographs with 10 kg weights right shoulder, c – Alexander radiograph left shoulder, d – Alexander radiograph right shoulder, arthroscopically supported vertical and horizontal stabilization with a TightRope, postoperative X-ray: e – Zanca, f – Outlet view.

Figure 5:

Male patient (55 y), right shoulder, chronic acromioclavicular joint instability with loss of reduction after surgical displacement of an acute Rockwood 3B injury 3 months ago (preoperative X-ray): a – Zanca stress radiograph with 10 kg weight, b – Alexander radiograph, c – arthroscopically supported vertical and horizontal stabilization with a TightRope and an additional autologous Hamstring-tendon augmentation, postoperative X-ray: d – Outlet view, e – a.p.