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

Implant Design and Its Applications in the Fixation of Osteoporotic Bones: Newer Technologies in Nails, Plates and External Fixators

Background

Osteoporosis, characterised by decreased bone mass and degradation of bone tissue, poses a major global health concern, particularly for the ageing population. The traditional fixation techniques often fail in osteoporotic bones due to their diminished density and strength. Technological advancements in orthopaedic implants, specifically nails, plates, and external fixators, have emerged to address these challenges.

Materials and Methods

Improvements in implant design focus on material properties, surface modifications, and geometric advancements. Titanium and its alloys are favoured for their biomechanical properties such as lower elastic modulus and high strength-to-weight ratio. The biodegradable materials like polylactic acid and magnesium alloys offer the advantage of gradual resorption as bone heals. Surface modifications, such as coatings with bioactive materials and drug-eluting surfaces, promote osseointegration and enhance fixation strength.

Results and Discussion

Intramedullary (IM) nails have evolved to enhance stability and minimise complications associated with osteoporotic fractures. Third and fourth-generation nails incorporate surface treatments for better integration and healing. The advances in screw design, locking mechanisms, and flexible axial stimulation have improved fixation and allowed micromotion, which promotes fracture healing. The use of external fixators, particularly for complex fractures in osteoporotic bones, offers less invasive treatment options with adaptable stiffness for improved healing.

Conclusion

Technological innovations in implant materials, design, and surgical techniques have significantly improved the management of osteoporotic fractures. Newer technologies, including 3D printing, virtual and augmented reality, and artificial intelligence, show promise in enhancing implant customization, surgical planning, and postoperative outcomes. However, further clinical validation and research are needed to expand their clinical applications.

Stable osteosynthesis of cage in cage technique for surgical treatment of proximal humeral fractures

Background

The treatment of a displaced proximal humeral fracture is still a matter of controversy. The purpose of this study was to report outcomes at a long-term follow-up after fixation augmentation using peek (polyether-ether-ketone) cage and locking compression plate (LCP).

Methods

A total of 27 patients (average age 53.8 years, range 19–86 years) were treated with peek cage and LCP. All of them had a minimum radiographic and clinical follow-up of 1 years. Outcomes were assessed using the Constant-Murley score (CMS), disability of the arm, shoulder and hand (DASH) score. Complications were also recorded during follow-up.

Results

The average follow-up was 28 months (range 12–48 months). The mean functional outcomes were as follows: CMS, 73.3 (range 61–86); DASH, 45.9 (range 27–68). A total of 4 patients had complications: osteonecrosis developed in one patient, loss of reduction was observed in 1 patient and stiffness was occurred in two patients.

Conclusion

The use of peek cage and LCP has been a valuable option in the treatment of proximal humeral fractures. The complication rate was acceptable. Suitable void filler in the proximal humerus for reconstructing the medial column integrity attains mechanical stability in reducing the incidence of the complications.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01235-x.

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.

Regulatory effect of miR-421 on humeral fracture and heterotopic ossification in elderly patients

The present study aimed to investigate the role of miR-421 and bone morphogenetic protein-2 (BMP-2) in the bone tissues and blood of elderly patients with humeral fractures and heterotopic ossification. A total of 38 patients with humeral fractures, including 16 patients who received surgery within 1-7 days of fracture and 22 patients who received surgery within 8-14 days of fracture, were enrolled. An additional 18 patients who had heterotopic ossification and 26 patients who had humeral fracture and not heterotopic ossification were also included. Bone tissues and blood were collected. Reverse transcription-quantitative polymerase chain reaction was performed to determine the miR-421 and BMP-2 mRNA expression levels in the samples. Western blotting and ELISA were performed to detect BMP-2 protein levels in bone tissues and blood, respectively. Dual-luciferase reporter assays were performed to verify whether BMP-2 is the direct target gene of miR-421. Compared with the patients who received surgery 1-7 days after fracture, the patients who accepted the surgery 8-14 days after fracture had significantly increased levels of BMP-2 mRNA and protein in their bone tissues and blood (P<0.05). Contrastingly, the expression level of miR-421 decreased in the samples from patients who accepted the surgery 8-14 days after fracture compared with the level in those who received surgery 1-7 days after fracture (P<0.05). Compared with the patients without heterotopic ossification, the patients with heterotopic ossification had increased BMP-2 mRNA and protein expression levels in their bone tissues and blood, whereas the expression of miR-421 was significantly decreased (P<0.05). The dual-luciferase reporter assay demonstrated that BMP-2 was the direct target gene of miR-421. The upregulation of BMP-2 may be associated with the downregulation of miR-421. miR-421 may regulate the recovery of humeral fracture and heterotopic ossification through BMP-2. The results of the present study may provide a theoretical basis for the diagnosis and treatment of humeral fracture and heterotopic ossification.

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.

Operative versus non-operative treatment in complex proximal humeral fractures: a meta-analysis of randomized controlled trials

Whether operative treatment for complex proximal humeral fractures (CPHFs) has a greater benefit over non-operative treatment remains controversial. There is no consensus on the optimal treatment in elderly patients with CPHFs. This updated meta-analysis of randomized controlled trials (RCTs) aims to investigate whether operative treatment is superior to non-operative treatment in CPHFs. The authors searched RCTs in the electronic databases (Cochrane Central Register of Controlled Trials, PubMed, EMBASE, Medline, Embase, Springer Link, Web of Knowledge, OVID and Google Scholar) from their establishment to July 2015. Researches on operative and non-operative treatment for CPHFs were selected in this meta-analysis. The quality of all studies was assessed and effective data was pooled for this meta-analysis. Outcome measurements were functional status include constant scores (CS scores) and disabilities of the arm, shoulder and hand scores (DASH scores), total complication rates and healthy-related quality of life. The meta-analysis was performed with software revman 5.3. Nine articles with a total 518 patients (average age 70.93) met inclusion criteria. Patients were followed up for at least 1 year in all the studies. No statistical differences were found between operative and non-operative treatment in CS scores at 12 mo (months) [MD 1.06 95 % CI (−3.51, 5.62)] and 24 mo [MD −0.61 95 % CI (−5.87, 4.65)]. There are also no statistical differences between operative and non-operative treatment in DASH scores at 12 mo [MD −4.51 95 % CI (−13.49, 4.47)] and 24 mo [MD −7.43 95 % CI (−16.14, 1.27)]. Statistical differences were found between operative and non-operative treatment in total complication rates [RR 1.55, 95 % CI (1.24, 1.94)]. Statistical differences in EQ-5D at 24 mo [MD 0.15, 95 % CI (0.05, 0.24)] were found between operative and non-operative treatment but no statistical differences were found in ED-5D at 12 mo [MD 0.08, 95 % CI (−0.01, 0.17)], 15D at 12 mo [MD 0.02, 95 % CI (−0.68, 0.73)] and 15D at 24 mo [MD 0.02, 95 % CI (−0.07, 0.83)]. Operative treatments did not significantly improve the functional outcome and healthy-related quality of life in elderly patients. Instead, Operative treatment for CPHFs led to higher incidence of postoperative complications.

Avascular necrosis in proximal humeral fractures in patients treated with operative fixation: a meta-analysis

BACKGROUND

Proximal humeral fractures are common lesions of the elderly, but there are no established treatment guidelines. A surgical treatment for comminuted and displaced fractures of the proximal humerus was developed and is still evolving. The aim of this study was to perform a quantitative review to evaluate the risk of avascular necrosis (AVN) in patients with proximal humeral fractures who were treated by operative fixation compared with conservative treatment.

METHODS

We searched the PubMed, MEDLINE, Springer, Elsevier Science Direct, Cochrane Library, Google Scholar, China National Knowledge Infrastructure (in Chinese), and Wanfang database (in Chinese) up to December 2013 to identify studies related to operative fixation and AVN in patients with proximal humeral fractures.

RESULTS

Seven studies with a total of 291 patients (142 operative fixation cases and 149 conservative treatment cases) with proximal humeral fractures were considered in the meta-analysis. The overall meta-analysis showed no significant difference in the incidence of AVN between the two groups [odds ratio (OR) 1.42, 95% confidence interval (CI) 0.33-6.11, p = 0.64]. The subgroup meta-analysis by study design (retrospective/prospective), sample size (≤40/>40), and ethnicity (European/Asian) demonstrated similar results. However, the subgroup analysis by specific operative approach (plate fixation/tension band wiring fixation/others) indicated that plate fixation was associated with a higher rate of AVN than conservative treatment (OR 0.20, 95% CI 0.05-0.76, p = 0.019).

CONCLUSIONS

Plate fixation was associated with a higher risk of AVN development than conservative treatment in patients with proximal humeral fractures.