Date Published: June 3, 2018
Author(s): Riccardo Luigi Alberio, Matteo Del Re, Federico Alberto Grassi.
The aim of this study was to evaluate the clinical and radiographic results after minimally invasive plate osteosynthesis (MIPO) for proximal humerus fractures. Potential advantages of this approach include the easier exposure of the greater tuberosity and the limited surgical dissection around the fracture site.
From October 2011 to March 2016, thirty-nine patients (32 women, 7 men) with a mean age of 64.9 years (range: 48–80) were surgically treated with the MIPO technique for proximal humeral fractures. According to Neer classification, there were 12 two-part, 24 three-part, and 2 four-part fractures and 1 two-part fracture-dislocation; the AO/OTA system was also used to categorize the fractures. The Constant-Murley (CMS) and the Oxford Shoulder (OSS) Scores were used to evaluate shoulder function.
Thirty-four patients were available for clinical and radiographic evaluation at a mean follow-up of 31.8 months (range: 12–54 months). All fractures healed and no postoperative complications occurred. Full recovery of pretrauma activities was reported by 27 patients, while 7 patients presented mild functional limitations. The mean absolute CMS was 75.2 (range: 55–95), the mean normalized CMS was 90.5 (range: 69–107), and the mean OSS was 43.7 (range: 31–48). The only statistically significant correlation was found between the female gender and lower absolute CMS and OSS. Radiographic evaluation revealed varus malunion in 4 cases and valgus malunion in 1 case, while incomplete greater tuberosity reduction was detected in 4 cases. All malunions were related to inadequate reduction at time of surgery and not to secondary displacement.
MIPO for proximal humeral fractures is an effective and safe surgical procedure. The limited tissue dissection allows minimizing the incidence of nonunion, avascular necrosis, and infection. The technique is not easy, requires experience to achieve mastery, and should be reserved for selected fracture patterns. In our experience, the main advantage of this approach consists in the direct access to the greater tuberosity, thus facilitating its anatomic reduction and fixation.
The incidence of proximal humerus fractures is increasing for two main reasons that reflect the bimodal distribution of these injuries. On one side, progressive aging of the population is associated with a rise in low energy injuries, particularly among women over 60 with osteopenia. On the other side, the wide participation in sport activities and the reduced mortality in traffic accidents are related to a growing rate of high-energy fractures requiring treatment [1, 2].
From October 2011 to March 2016, thirty-nine patients were surgically treated with the MIPO technique for displaced proximal humerus fractures by a single surgeon at a single institution. In this clinical series, neither a treatment protocol nor inclusion/exclusion criteria were preventively established. The MIPO technique was performed for fractures in which reduction and plating had reasonable chances of success without exposing the anteromedial aspect of the proximal humerus. Fractures with wide diastasis between fragments, high-energy injuries with relevant soft tissue interposition between bone fragments, four-part fractures (excluding valgus impacted), and articular (head-splitting or severely impacted) fractures were not considered suitable for the MIPO technique. These lesions were either plated through a deltopectoral approach or treated with shoulder arthroplasty.
Thirty-four patients were available for clinical and radiographic evaluation at a mean follow-up of 31.8 months (range: 12 to 54 months). Four patients declined to show up for logistical problems, while one patient was untraceable. All dropouts (12.8%) were women; therefore the last follow-up population included 27 female and 7 male patients with a mean age of 64.8 years (range: 48 to 80 years).
Progressive aging of population is the most important factor contributing to the increasing incidence of proximal humeral fractures in highly developed countries [1, 2]. Most of these lesions can be successfully treated by conservative means, but in many cases surgical treatment is required and several options are available.