Serial changes in the head-shaft angle of proximal humeral fractures treated by placing locking plates: a retrospective study

What Are the Long-term Outcomes of Locking Plates for Nonosteoporotic Three-part and Four-part Proximal Humeral Fractures With a Minimum 10-year Follow-up Period?

BACKGROUND

Proximal humeral fractures (PHFs) often occur in elderly individuals who experience low-energy falls. Open reduction and internal fixation (ORIF) of the proximal humerus is typically performed in young, active patients because of their good bone quality and high functional demands. Although good short-term results have been reported after ORIF in young patients, few studies have specifically evaluated long-term outcomes.

QUESTIONS/PURPOSES

(1) What are the long-term clinical outcomes scores and (2) radiologic outcomes of nonosteoporotic three-part and four-part PHFs treated with locking plates? (3) What complications occurred after treatment, and what factors are associated with poor postoperative functional outcomes scores and avascular necrosis (AVN) of the humeral head after ORIF?

METHODS

Between June 2005 and December 2012, we surgically treated 774 patients for displaced two-, three-, and four-part PHFs. Approximately 75% (581 of 774) underwent ORIF, 10% (77 of 774) underwent hemiarthroplasty, 7% (54 of 774) underwent intramedullary nailing, 5% (39 of 774) underwent reverse shoulder arthroplasty, and the remaining 3% (23 of 774) underwent other surgical treatments. We considered those who had ORIF as potentially eligible. Based on that criterion, 75% (581) were eligible. However, only patients with nonosteoporotic three- and four-part PHFs (cortical thickness of the proximal humeral diaphysis greater than 6 mm on a preoperative AP radiograph of the affected shoulder) and a minimum of 10 years of follow-up were included. Sixty-four percent (498 of 774) of the patients were excluded because of simple or osteoporotic fractures, 1% (7 of 774) were excluded because of ipsilateral limb multiple fractures, 0.3% (2 of 774) were excluded because of pathologic PHFs, and another 2% (13 of 774) were lost before the minimum study follow-up of 10 years, leaving 8% (61 of 774) for analysis here. The mean age at surgery was 45 ± 12 years, with a mean follow-up of 13 years. Fifty-seven percent (35 of 61) of the patients were men. Patient-reported outcomes were evaluated using the University of California Loas Angeles (UCLA) score (range 0 to 35; higher scores represent better shoulder function) and Constant score (range 0 to 100; higher scores represent better shoulder function) at least 10 years postoperatively. Postoperative radiographs were reviewed to assess the cortical bone thickness of the proximal humerus, neck-shaft angle, head-to-tuberosity distance, and radiologically confirmable complications. Logistic regression analysis was performed to evaluate factors associated with poor postoperative functional scores (UCLA score ≤ 27 or Constant score ≤ 70) and AVN of the humeral head; the association between AVN and postoperative functional outcomes was also assessed.

RESULTS

At the most-recent follow-up, these patients had a mean UCLA score of 31 ± 3 and a Constant score of 88 ± 10. The mean neck-shaft angle was 133° ± 10°, and 23% (14 of 61) of patients experienced AVN of the humeral head during follow-up. Twenty-nine complications in 30% (18 of 61) of patients were reported. After controlling for potentially confounding variables such as age and gender, we found that the presence of greater tuberosity malposition (odds ratio 18 [95% confidence interval 2 to 167]; p = 0.01) and immediate postoperative neck-shaft angle less than 130° (OR 19 [95% CI 3 to 127]; p = 0.002) were associated with poor postoperative functional scores. Four-part PHFs (OR 13 [95% CI 2 to 82]; p = 0.008) and metaphyseal extension less than 8 mm (OR 7 [95% CI 1 to 35]; p = 0.03) were associated with AVN of the humeral head. For patients who met the criteria for anatomic reduction (achievement of all of the following three criteria: neck-shaft angle ≥ 130°, head-shaft displacement < 5 mm, and head-to-tuberosity distance greater than or equal to 3 mm and less than or equal to 20 mm), there were no differences in postoperative functional scores between patients with AVN and those without.

CONCLUSION

ORIF of nonosteoporotic proximal humeral fractures with locking plates led to favorable functional and radiologic outcomes at a minimum of 10 years of follow-up. When encountering complex PHFs in patients with good bone quality, every effort must be made to achieve an anatomic reduction of the fracture as far as possible, which may not reduce the risk of AVN (this occurred in nearly one-fourth of patients). However, good outcomes can usually be expected, even in patients with AVN. Because this was a retrospective study with a high risk of bias owing to sparse data, the factors associated with poor postoperative functional outcomes must be further investigated in large prospective studies.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Preventing secondary screw perforation following proximal humerus fracture after locking plate fixation: a new clinical prognostic risk stratification model

INTRODUCTION

After locking plate (LP) fixation, secondary screw perforation (SSP) is the most common complication in proximal humerus fracture (PHF). SSP is the main cause of glenoid destruction and always leads to reoperation. This study aimed to identify independent risk parameters for SSP and establish an individualized risk prognostic model to facilitate its clinical management.

METHODS

We retrospectively reviewed the medical information of patients with PHF who underwent open reduction and internal LP fixation at one medical center (n = 289) between June 2013 and June 2021. Uni- and multivariate regression analyses identified the independent risk factors. A novel nomogram was formulated based on the final independent risk factors for predicting the risk of SSP. We performed internal validation through concordance indices (C-index) and calibration curves. To implement the clinical use of the model, we performed decision curve analyses (DCA) and risk stratification according to the optimal cutoff value.

RESULTS

A total of 232 patients who met the inclusion criteria were enrolled. The incidence of SSP was 21.98% at the last follow-up. We found that fracture type (odds ratio [OR], 3.111; 95% confidence interval [CI], 1.223-7.914; P = 0.017), postoperative neck-shaft angle (OR, 4.270; 95% CI 1.622-11.239; P = 0.003), the absence of calcar screws (OR, 3.962; 95% CI 1.753-8.955; P = 0.003), and non-medial metaphyseal support (OR,7.066; 95% CI 2.747-18.174; P = 0.000) were independent predictors of SSP. Based on these variables, we developed a nomogram that showed good discrimination (C-index = 0.815). The predicted values of the new model were in good agreement with the actual values demonstrated by the calibration curve. Furthermore, the model's DCA and risk stratification (cutoff = 140 points) showed significantly higher clinical benefits.

CONCLUSIONS

We developed and validated a visual and personalized nomogram that could predict the individual risk of SSP and provide a decision basis for surgeons to create the most optional management plan. However, future prospective and externally validated design studies are warranted to verify our model's efficacy.

Reduction and fixation of proximal humeral fracture with severe medial instability using a small locking plate

BACKGROUND

Currently, the reduction and support of comminuted medial cortex of humeral fracture remains a challenge, Therefore, a novel reduction and fixation technique that employs an anteromedial small locking plate was explored in this study, and its viability and the associated complications were assessed.

METHODS

Fifteen cases of proximal humeral fractures with medial instability (five cases were classified as three-part and ten as four-part by Neer classification) were treated by the proposed reduction technique using an anteromedial small locking plate. Subsequently, the radiological and clinical outcomes were evaluated over an average follow-up period of 18.53 months.

RESULTS

The average operation time was 108 min (range, 70-130 min), and the mean fracture union time in all patients was 12.13 weeks (range, 8-16 weeks). Complications such as infection and neurovascular injury were not observed. Postoperative X-ray showed avascular necrosis and screw penetration in one patient, while screw penetration, varus malunion, or significant reduction loss was not found in the other cases. The mean Constant score was 79.8 (range, 68-92) during the final visit.

CONCLUSIONS

The use of an anteromedial small locking plate improved the reduction efficiency, reconstructed the medial support, and alleviated the occurrence of complications in proximal humeral fractures with medial instability.

Radiographic parameter(s) influencing functional outcomes following angular stable plate fixation of proximal humeral fractures

PURPOSE

Radiographic parameters which correlate with poor clinical outcome after proximal humeral fractures could be helpful indicators to answer the question which patients should be followed up closer. Moreover, during surgery, radiographic parameters correlating with unfavourable outcome should be avoided. The primary aim of the study was to compare radiographic measurements between the injured and the contralateral, uninjured shoulder. The secondary aim was to correlate these radiographic parameters with post-operative shoulder function.

METHODS

Fifty-eight patients (age: 55.6 ± 14.4 years, age at surgery) following angular stable plate fixation of a proximal humeral fracture (2-part fractures according to Neer: 24, 3-part: 25, 4-part: 9) were included in this retrospective cohort study. All patients were followed up at least six years (7.9 ± 1.4 after surgical intervention). During follow-up examination, the Constant score (CS) was assessed, and radiographs of both shoulders were taken. Radiographs were analyzed regarding lateral humeral offset, distance between tuberculum and head apex, head diameter, head height, perpendicular height, perpendicular center, vertical height, and angles between head and humeral shaft (CCD and HSA). These parameters were compared between the injured and uninjured shoulder. The cohort was divided in two groups: patients with a CS category of excellent/good and satisfying/worse. Both groups were tested regarding differences of demographic and radiographic parameters.

RESULTS

The distance between tuberculum and head apex (2.6 ± 3.4 mm vs. 4.3 ± 2.1 mm; p = 0.0017), the CCD (123.1 ± 12.9° vs. 130.1 ± 7.3°; p = 0.0005), and the HSA (33.1 ± 12.8° vs. 40.1 ± 7.3°; p = 0.0066) were significantly smaller on the treated shoulder compared to the uninjured side. Patients reached a Constant score of 80.2 ± 17.4 (95% CI 75.6-84.8) points. Regarding outcome categories of the Constant score, 46 patients had a good to excellent outcome, and 12 patients had a satisfying or bad outcome. The comparison of these groups revealed that patients with inferior outcome in the long-term follow-up were older, female, had a more complex fracture type (AO classification), smaller lateral humeral offset, smaller head diameter and height, lower perpendicular height, and lower CCD and HSA angles.

CONCLUSION

If the abovementioned parameters cannot be restored sufficiently during surgery, (reversed) shoulder arthroplasty might be a better solution to reach good post-operative outcome. Moreover, patients presenting these radiographic characteristics in the follow-up, older patients, and patients with a more complex fracture type should be followed up closer to possibly prevent poor shoulder function.

TRIAL REGISTRATION

83 250/2011BO2.

Factors associated with maintaining reduction following locking plate fixation of proximal humerus fractures: a population-based retrospective cohort study

Background

Loss of reduction (LoR) can occur after locking plate fixation of proximal humerus fractures (PHFs). This study determined biomechanical features of fracture fixation associated with preventing LoR postoperatively. One-year reoperation rates were also compared between those with/without LoR.

Methods

Population-based administrative data for 359 adults treated using a locking plate for PHF between 2010 and 2016 were examined. Two trained assessors reviewed standardized shoulder radiographs. LoR (Yes/No) was defined as any fracture displacement >0.5 cm, and/or >10° change in neck-shaft angle (NSA) alignment relative to intraoperative imaging. Multiple logistic regression assessed how the following affected maintaining reduction: (1) sex, (2) age, (3) Neer classification, (4) shaft impaction (SI), (5) shaft medialization (SM), (6) calcar reduction (CR), (7) NSA alignment, and (8) screw use.

Results

LoR was seen in 79 (22%) patients. LoR was significantly associated with increasing age (odds ratio [OR] = 1.06/yr, P < .001), fracture severity (4-part vs. 2-part fracture; OR = 4.63, P = .001), and varus NSA alignment (<125° vs. ≥145°: OR = 5.6, P = .02; <125° vs. 125-145°, OR = 2.2, P = .02]). Patients achieving simultaneous SI, SM, and CR were significantly less likely (OR = 0.009, P < .001) to lose reduction, after controlling for age, fracture severity, and NSA alignment. If only SI was achieved, patients were still significantly less likely to lose reduction relative to achieving none of these mechanical features (OR = 0.17, P = .006). Reoperations were higher when LoR occurred (n = 26/77 [33.4%]) compared with no LoR (n = 20/276 [7.2%]) (P < .001).

Conclusions

SI was strongly associated with preventing LoR in patients treated using a locking plate for PHF. SI with concurrent SM, CR, and a neutral or valgus NSA had the lowest rates of LoR. LoR was associated with higher rates of reoperation.

Late screw-related complications in locking plating of proximal humerus fractures: A systematic review

Locking plating is a common surgical treatment of proximal humeral fractures with satisfactory clinical results. Implant-related complications, especially screw-related, have been reported, however, the lack of information regarding their onset, used surgical technique, complexity of the fracture, bone quality etc., prevents from understanding the causes for them. The aim of this systematic review is to identify the potential risk factors for late screw complications by gathering information about the patient characteristics, comorbidities, fracture types, surgical approaches and implant types. A PubMed search was performed using humerus, fractures, bone and locking as keywords in clinical papers written in English. All abstracts and manuscripts on distal or humerus shaft fractures, and those on proximal humerus fractures without any or with only iatrogenic complications were excluded. One hundred studies met the inclusion criteria, resulting in 33% of the reported cases having at least one complication, with 11% of all complications being screw-related. Most of the latter were secondary screw perforations and screw cut-outs, being predominantly linked to poor bone quality, while screw loosening and retraction were found less frequently as a result of locking mechanism failure. Overall, the amount of information for complications was limited and screw perforation was the most frequent screw-related complication, mostly reported in female patients older than 50 years, following four-part or AO/OTA type C fractures and detected four weeks postoperatively. The sparse information in the literature could be an indicator that the late screw complications might have been under-reported and under-described, making the understanding of the screw-related complications even more challenging.