Effects of medial support screws on locking plating of proximal humerus fractures in elderly patients: a retrospective study

Risk factors for osteonecrosis of the humeral head after internal fixation of proximal humeral fractures: a systematic review and meta-analysis

BACKGROUND

Osteonecrosis of the humeral head (ONHH) is a severe complication after the internal fixation of proximal humeral fractures (IFPHF). The risk factors remain controversial though many studies have reported. In this research, meta-analysis was used to evaluate which surgeon-level factors can be modified to lower the risk and we hope to provide evidence-based support for preventing ONHH.

METHODS

Literature was retrieved from PubMed, Cochrane Library, Embase, Web of Science, and Scopus for eligible studies published up to January 2023. The pooled odds ratios (ORs) were calculated with their corresponding 95% confidence intervals (CIs) to evaluate. STATA 15.1 software was applied for data synthesis, sensitivity synthesis, and publication bias.

RESULTS

45 articles were published between 2000 and 2022, and 2482 patients were finally included. All articles were observational research, with 7 case-control studies and 38 cohort studies, and the Newcastle Ottawa Scale (NOS) score ranged from 7 to 9. The pooled results suggested that age (OR 0.32, 95% CI 0.14-0.74, P = 0.01), reduction quality (OR 0.08, 95% CI 0.01-0.44, P = 0.00), fracture type (OR 0.44, 95% CI 0.25-0.78, P = 0.01), surgical approach (OR: 4.06, 95% CI 1.21-13.61, P = 0.02) and fixation implant (OR = 0.68, 95% CI = 0.34-1.33, P = 0.02) were risk factors for ONHH after IFPHF. According to sensitivity analysis, Begg (P = 0.42) and Egger (P = 0.68) tests, the results were stable and exhibited no publication bias.

CONCLUSIONS

The study showed that age, reduction quality, fracture type, surgical approach and fixation implant were risk factors for ONHH after IFPHF, while gender, varus or valgus, timely operation, injured side, and the existence of medial support have little influence on ONHH, as they could not be considered risk factors and still need further investigations.

Application of a lateral intertubercular sulcus plate in the treatment of proximal humeral fractures: a finite element analysis

Background

Inversion deformities caused by insufficient medial support are especially common when the PHILOS locking plate is used to treat proximal humeral fractures. Using finite element analysis, we aimed to compare the biomechanical properties of a PHILOS locking plate (PLP) and a PLP combined with a lateral intertubercular sulcus plate (PLP-LSP) in the fixation of proximal humeral fractures with loss of the medial column.

Methods

After creating a three-dimensional finite element model of a proximal humeral fracture with loss of the medial column, three implant models were established. A full-screw PLP was used in Group A, a PHILOS plate lacking medial screw support and an additional steel plate (MPLP-LSP) were used in Group B, and a full-screw PLP-LSP was used in Group C. The three fixation models were applied to the proximal humeral fracture model, following which horizontal, compressive, and rotational loads were applied to the humerus model. We evaluated structural stiffness and stress distribution in the implant and compared displacement and angle changes among the three models.

Results

Displacement and angle changes were smallest in Group C (PLP-LSP). The implant model used in Group C also exhibited greater structural rigidity, endured less von Mises stress, and was more stable than the models used in Group A and Group B.

Conclusion

An LSP placed at the intertubercular sulcus provides effective lateral and medial support, thereby reducing stress on the PLP and providing better stability with proximal humeral fractures.

The association of homocysteine, folate, vitamin B12, and vitamin B6 with fracture incidence in older adults: a systematic review and meta-analysis

Background

Diverse conclusions have been drawn regarding the association of homocysteine (HCY) deficiency and supplements of B vitamins with fracture incidence in older adults. The aim of this meta-analysis was to investigate the association of HCY and B vitamins (folate, vitamin B12, and B6) with fracture incidence in older adults and whether supplements of B vitamins reduce the risk of fracture.

Methods

The PubMed, Embase, and Cochrane library databases were systematically searched from their inception dates to 1 July 2019 to identify relevant published articles. Meta-analysis was performed to pool hazard ratios (HRs) or risk ratios (RRs) and 95% confidence intervals (CIs) using a random effects model.

Results

A total of 28 studies fulfilled the inclusion criteria. High serum HCY was an independent risk factor for fractures in older persons (HR =1.25, 95% CI: 1.12 to 1.40), but only at the highest quartile level (>15 µmol/L) (HR =1.71, 95% CI: 1.37 to 2.12), rather than the second and third quartile. Multiple sensitivity and subgroup analyses supported the consistency and stability of this result. A severe deficiency of folate, instead of vitamin B12 and B6, was found to increase the risk of fracture in older adults (HR =1.46, 95% CI: 1.06 to 2.02; 1.24, 95% CI: 0.79 to 1.95; 1.36, 95% CI: 0.90 to 2.06, respectively). For the interventional effect, there was no significant association of combined folate and vitamin B12, combined folate, vitamin B12 and B6, or single vitamin B6 supplementation with the decrease of fracture risk.

Discussion

This meta-analysis revealed that significantly elevated serum level of HCY is positively associated with fracture incidence in older adults, yet the necessity and threshold for intervention by B vitamins require further large-scale high-quality clinical trials to validate.

PROSPERO identifier

CRD42019122586.

A novel surgical approach and technique and short-term clinical efficacy for the treatment of proximal humerus fractures with the combined use of medial anatomical locking plate fixation and minimally invasive lateral locking plate fixation

BACKGROUND AND HYPOTHESIS

The typical anterolateral approach is widely used to treat proximal humerus fractures with lateral locking fixation. However, lateral fixation cannot completely avoid medial reduction loss and varus deformity especially in the cases of an unstable medial column. We present a novel medial surgical approach and technique together with a minimally invasive lateral locking plate to fix proximal humerus fractures with an unstable medial column.

MATERIALS AND METHODS

We performed an anatomical study and reported 8 cases of proximal humerus fractures with unstable medial columns treated with plate fixation through a minimally invasive anterolateral approach and medial approach. All surgeries were performed by the same single surgeon. Patients were followed clinically and radiographically at 1, 3, 6, and 12 months postoperatively.

RESULTS

There was a safe region located at the medial part of the proximal humerus just beneath the articular surface. An anatomical medial locking proximal humerus plate could be placed in the medial column and did not affect the axillary nerve, blood supply of the humeral head, or stability of the shoulder joint. Successful fracture healing was achieved in all 8 cases. The function and range of motion of the shoulder joint were satisfactory 24 months postoperatively, with an average Constant score (CS) of 82.8. No reduction loss (≥ 10° in any direction), screw cutout, nonunion, or deep infection occurred.

CONCLUSIONS

The combined application of medial anatomical locking plate fixation and minimally invasive lateral locking plate fixation is effective in maintaining operative reduction and preventing varus collapse and implant failure in proximal humerus fractures with an unstable medial column.