Da Vinci System: clinical experience with complex proximal humerus fractures

Synthetic Bone Substitutes and Mechanical Devices for the Augmentation of Osteoporotic Proximal Humeral Fractures: A Systematic Review of Clinical Studies

BACKGROUND

Different augmentation techniques have been described in the literature in addition to the surgical treatment of proximal humeral fractures. The aim of this systematic review was to analyze the use of cements, bone substitutes, and other devices for the augmentation of proximal humeral fractures.

METHODS

A systematic review was conducted by using PubMed/MEDLINE, ISI Web of Knowledge, Cochrane Library, Scopus/EMBASE, and Google Scholar databases according the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines over the years 1966 to 2019. The search term "humeral fracture proximal" was combined with "augmentation"; "polymethylmethacrylate, PMMA"; "cement"; "bone substitutes"; "hydroxyapatite"; "calcium phosphates"; "calcium sulfate"; "cell therapies", and "tissue engineering" to find the literature relevant to the topic under review.

RESULTS

A total of 10 clinical studies considered eligible for the review, with a total of 308 patients, were included. Mean age at the time of injury was 68.8 years (range of 58-92). The most commonly described techniques were reinforcing the screw-bone interface with bone PMMA cement (three studies), filling the metaphyseal void with synthetic bone substitutes (five studies), and enhancing structural support with metallic devices (two studies).

CONCLUSION

PMMA cementation could improve screw-tip fixation. Calcium phosphate and calcium sulfate injectable composites provided good biocompatibility, osteoconductivity, and lower mechanical failure rate when compared to non-augmented fractures. Mechanical devices currently have a limited role. However, the available evidence is provided mainly by level III to IV studies, and none of the proposed techniques have been sufficiently studied.

Triangular block bridge method for surgical treatment of complex proximal humeral fractures: theoretical concept, surgical technique and clinical results

INTRODUCTION

Criteria for classification, indication and choice of a surgical device to treat proximal humeral fractures are still controversial. We report an original technique based on a mechanical concept with a structural principle of a triangle as a rigid body applied to the humeral head fractures in association with other devices. This retrospective study aims to describe in detail the surgical technique and results at long time follow up.

METHODS AND MATERIAL

We analysed two series of 101 patients with proximal humeral fractures (mean age, 52.9 y; range 19-78 y) treated between 2001 and 2012 reporting the clinical and radiological results. In the first series of 23 cases (mean age 51.4 y, range 35-74 y) we used as support a bone piece taken from allograft or autologous tricortical iliac crest and shaped as a triangular pyramid during the operation; while in the second series of 78 cases (mean age 53.6 years, range 29-78 years, SD 13.5 years) a triangular titanium cage was used in 69 patients while in 9 allograft or bone substitute was used as augmentation. An analytical retrospective study was done to understand the mechanical function of medial augmentation composed by a solid body in association with different types of synthesis to stabilize properly a proximal humeral fracture.

RESULTS

We obtained excellent and good results in 83,2% of patients, fair in 12,8% and bad in 4% in terms of active anterior elevation, external and internal rotation, pain and strength according to Constant and DASH score.

CONCLUSION

A medial solid body, especially in titanium material and shaped as trapezoidal/pyramidal form used to fill the secondary bone loss in complex instable proximal humeral fracture, allows an anatomic reduction and stable fixation in association with simple and more complex tools and it provides a better biomechanical environment for union and maintenance of alignment.

Management of proximal humerus fractures in adults

The majority of proximal humerus fractures are low-energy osteoporotic injuries in the elderly and their incidence is increasing in the light of an ageing population. The diversity of fracture patterns encountered renders objective classification of prognostic value challenging. Non-operative management has been associated with good functional outcomes in stable, minimally displaced and certain types of displaced fractures. Absolute indications for surgery are infrequent and comprise compound, pathological, multi-fragmentary head-splitting fractures and fracture dislocations, as well as those associated with neurovascular injury. A constantly expanding range of reconstructive and replacement options however has been extending the indications for surgical management of complex proximal humerus fractures. As a result, management decisions are becoming increasingly complicated, in an attempt to provide the best possible treatment for each individual patient, that will successfully address their specific fracture configuration, comorbidities and functional expectations. Our aim was to review the management options available for the full range of proximal humerus fractures in adults, along with their specific advantages, disadvantages and outcomes.

Reconstruction of unstable, complex proximal humeral fractures with the da Vinci cage: surgical technique and outcome at 2 to 6 years

BACKGROUND

Treatment of displaced proximal humeral fractures remains a challenge for the orthopaedic surgeon. We describe the reconstruction of such fractures with a new device designed to provide good medial cortex support and report treatment outcome.

MATERIALS AND METHODS

The da Vinci device is an open triangular prism made of titanium. It is inserted in the proximal humeral cavity to stabilize the humeral head and tuberosities. Between May 2005 and December 2010, we treated 81 patients with unstable dislocated proximal fractures using this device. We report the outcome of the 69 patients monitored for at least 2 years.

RESULTS

The results, based on the Constant-Murley and Disabilities of the Arm, Shoulder and Hand scores at a minimum of 2 years' follow-up, were excellent in 36 of 69 patients, good in 29, fair in 2, and poor in the remaining 2. Successful fracture healing was obtained in 68 of 69 patients, whereas the cage was removed in 1 patient 80 days after surgery because of infection. Partial vascular osteonecrosis occurred in 5 patients but was clinically symptomatic in only 1 of these. Fragment reduction was maintained during follow-up in all 68 cases.

CONCLUSIONS

The da Vinci cage results in good reduction and stable fixation of displaced proximal humeral fractures, as well as in cases of humeral head dislocation and comminuted fractures. Unlike other devices and screwed plates, it does not invade the subacromial space and osteosynthesis is minimally invasive.

LEVEL OF EVIDENCE

Level IV, Case Series, Treatment Study.

The classification of complex 4-part humeral fractures revisited: the missing fifth fragment and indications for surgery

We describe a new classification of complex 4-part proximal humeral fractures (PHF). Its novelty lies in the involvement of fractures of the calcar area (i.e., the missing fifth fragment) in relation to fragments of the head, tuberosities and shaft. The classification consists of 6 groups (divided into 15 subgroups) of calcar fracture patterns. We hypothesized that this classification could aid surgical decision making in terms of osteosynthesis versus prothesis. To test this hypothesis, two shoulder surgeons, trained in the classification, re-examined the X-rays and CT scans of 100 cases of 4-part PHF to codify each calcar fracture pattern. CT scans proved to be essential for this process. We then theoretically assigned the most appropriate treatment to each subgroup. Subsequent verification of clinical records confirmed our hypothesis that this classification could help the surgeon to decide the best approach to complex 4-part PHF.