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Measurement of the head-shaft-angle. Drawing a line from the superior to the inferior border of the articular surface of the humerus (A line) and then a perpendicular to the A line through the center of the humeral head (B line). The angle (α) between the B line and the line bisecting the humeral shaft (C line) was measured as the head-shaft angle.
Source publication
The aim of the study was to examine the correlation between the chosen position of screws and the complications observed in patients who underwent locked plating of proximal humeral fractures. We evaluated radiographs of 367 patients treated by locked-plating for proximal humeral fractures. Radiographs were taken at one day, 6 weeks, 3 months and 6...
Context in source publication
Context 1
... head-shaft- angle was measured drawing a line from the superior to the inferior border of the articular surface through the anatomical neck of the humerus (A line) and then a perpendicular line to the A line through the center of the humeral head (B line). The angle () between the B line and the line bisecting the humeral shaft (C line) was measured as the head-shaft angle ( Figure 2). Loss of fixation was defined as a varus displacement of more than 10 degrees in true a.p. ...Similar publications
Aim
This study aimed to assess the efficacy of three-dimensional (3D) printing to conventional surgeries in proximal humerus fractures (PHFs).
Methods
Eight databases were comprehensively searched for data on clinical characteristics and outcomes, including operation time, time to bone healing, blood loss volume, number of intraoperative fluorosco...
Background:
Age-related changes in the medial column (MC) of the proximal humerus have a major impact on fracture management; however, the changes in the morphological features remain unclear. This study aimed to investigate the age-related changes in the morphological features of MC and present the morphological grading.
Methods:
One hundred co...
Purpose:
The aim of this study was to quantify the rate of complications and reinterventions in patients treated with PHILOS plate for proximal humerus fractures (PHFs) synthesis.
Methods:
A comprehensive literature search was performed on the PubMed, Web of Science, Embase, and Cochrane databases up to 7 October 2021. Studies describing medium...
Background
Inferior subluxation of the humeral head is frequently observed immediately after surgery for proximal humerus fractures; however, the incidence and risk factors of inferior subluxation after osteosynthesis for isolated greater tuberosity fractures remain unsolved. Additionally, the postoperative course of inferior subluxation has not be...
Background:
Although the Neer classification is widely used for the assessment of proximal humeral fractures, its reproducibility has been challenged. The purpose of this study was to evaluate the reproducibility of the conventional Neer classification and a modified classification that defined fracture displacement with respect to the humeral hea...
Citations
... Another confounder for precise measurements of pegs or screws is the quality of radiographs, depending on a precise angulation of the X-ray beam and an antegrade plate projection, as shown in the Fig. 3 radiographs. This was taken into account with standardized radiographic examinations for all included patients [33]. ...
Background
Angular stable plates were introduced two decades ago as a promising treatment for fixation of displaced fractures of the proximal humerus (PHF). However, high rates of adverse events and reoperations have been reported. One frequent reason is secondary penetration of screws into the glenohumeral joint, due to sinking of the fracture or avascular head necrosis. To prevent joint penetrations angular stable plates with smooth locking pegs instead of locking screws have been developed. The aim of the present study was to investigate whether blunt pegs instead of pointed screws reduced the risk of secondary penetration into the glenohumeral joint during fracture healing after operatively treated PHFs.
Methods
From two different patient cohorts with displaced PHFs (60 treated with PHILOS plate with screws and 50 with ALPS-PHP plate with pegs), two groups were matched according to fracture type AO/OTA 11-B2 and 11-C2 and age (55–85 years). They were followed up at 3, 6 and 12 months. Primary outcome was radiographic signs of peg or screw penetrations into the glenohumeral joint at 12 months. Secondary outcomes were Oxford shoulder score (OSS) and Constant Score (CS) and radiographic signs of avascular humeral head necrosis (AVN).
Results
Eighteen PHILOS patients with B2 and C2 fractures could be matched with a corresponding group of 18 operated with ALPS-PHP with pegs. The number of penetrations of pegs and screws were equal between the two groups and the development of avascular head necrosis did not differ either. The functional outcomes for both OSS and CS at 12 months was clearly in favor of patients without joint penetrations in both groups.
Conclusion
We found no differences in the number of screw or peg penetrations in the PHILOS and ALPS-PHP group and the occurrence of AVN was equal. Joint penetrations led to inferior functional outcomes at 1 year.
The ClinicalTrials.gov identifier 20/11/12 prospectively for the Philos Group is NCT01737060, and for the ALPS group 11/03/20 retrospectively is NCT04622852.
... There was a scarcity of previously reported data that focus on the essential number of proximal screws necessary for a stable fixation of a proximal humerus fracture. 31,32 Maddah et al. conducted a retrospective investigation on the correlation between screw position and complications observed in 367 patients who underwent proximal humeral fracture fixation with a locking plate. 31 Serial radiographic observations showed that the loss of fixation was observed in 15.8% (58 of 367) of the patients, and among those, cutting out of screws was found in 6.8%. ...
... 31,32 Maddah et al. conducted a retrospective investigation on the correlation between screw position and complications observed in 367 patients who underwent proximal humeral fracture fixation with a locking plate. 31 Serial radiographic observations showed that the loss of fixation was observed in 15.8% (58 of 367) of the patients, and among those, cutting out of screws was found in 6.8%. In patients with secondary loss of fixation, an average of 6.7 screws were used to fix the fracture but without significant result from statistical analysis. ...
Purpose
This biomechanical study investigates the optimal number of proximal screws for stable fixation of a 2-part proximal humerus fracture model with a locking plate.
Methods
Twenty-four proximal humerus fracture models were included in the study. An unstable 2-part fracture was created and fixed by a locking plate. Cyclic loading and load-to-failure tests were used for the following 4 groups based on the number of screws used: 4-screw, 6-screw, 7-screw, and 9-screw groups. Interfragmentary gaps were measured following cyclic loading and compared. Consequently, the load to failure, maximum displacement, stiffness, and mode of failure at failure point were compared.
Results
The interfragmentary gaps for the 4-screw, 6-screw, 7-screw, and 9-screw groups were significantly reduced by 0.24 ± 0.09 mm, 0.08 ± 0.06 mm, 0.05 ± 0.01 mm, and 0.03 ± 0.01 mm following 1000 cyclic loading, respectively. The loads to failure were significantly different between the groups with the 7-screw group showing the highest load to failure. The stiffness of the 7-screw group was superior compared with the 6-screw, 9-screw, and 4-screw groups. The maximum displacement before failure showed a significant difference between the comparative groups with the 4-screw group having the lowest value. The 7-screw group had the least structural failure rate (33.3%).
Conclusion
At least 7 screws would be optimal for proximal fragment fixation of proximal humerus fractures with medial comminution to minimize secondary varus collapse or fixation failure.
Level of Evidence
Basic science study.
... This choice was based on the fact that distal screws are typically bicortical with inherent stability. Furthermore, the top level of screws was present in all the configurations, as this is a common clinical practice [24]. Only one plate position was simulated. ...
Internal fixation with use of locking plates is the standard surgical treatment for proximal humerus fractures, one of the most common fractures in the elderly. Screw cut-out through weak cancellous bone of the humeral head, which ultimately results in collapse of the fixed fracture, is the leading cause of failure and revision surgery. In an attempt to address this problem, surgeons often attach the plate with as many locking screws as possible into the proximal fragment. It is not thoroughly understood which screws and screw combinations play the most critical roles in fixation stability. This study conducted a detailed finite element analysis to evaluate critical parameters associated with screw cut-out failure. Several clinically relevant screw configurations and fracture gap sizes were modeled. Findings demonstrate that in perfectly reduced fracture cases, variation of the screw configurations had minor influence on mechanical stability of the fixation. Effects of screw configurations became substantial with existence of a fracture gap. Interestingly, use of a single anterior calcar screw was as effective as utilizing two screws to support the calcar. On the other hand, variation in calcar screw configuration had minor influence on the fixation stability when all the proximal screws (A-D level) were filled. This study evaluates the different screw configurations to further understand the influence of combined screw configurations and the individual screws on the fixation stability. Findings from this study may help decrease the risk for screw cut-out with proximal humerus varus collapse and the associated economic costs.
... 2,9 However, screw cutout has been identified as a frequent postoperative complication, occurring at a rate ranging from 5.4% to 23% as reported in the literature. 3,14,18,19,[23][24][25] Several authors have attempted to identify factors that may lead to a higher rate of complications following locked-plate fixation including the AO type C fracture pattern, 7 compromised vascularity of the humeral head fragment, 7 insufficient medial support and comminution, 10,13,21 initial coronal displacement in varus, 7,10 osteoporosis, 10,13 and older age. 2 Multiple surgical improvements have also been suggested to decrease complications, including using more screws in the humeral head, 5 ensuring mechanical support of the inferomedial proximal humerus, 5,6,21 augmenting the fracture site with calcium phosphate cement, 4 and using a supplemental endosteal fibular strut. 8,16,17 Although there are not specific indications for when to obtain a computed tomography (CT) scan for proximal humeral fractures, they are frequently obtained as they can provide additional information about the nature of a fracture that cannot be obtained from plain films. ...
Hypothesis and/or Background
Preoperative Computerized Tomography (CT) scan can be used to measure thickness of the center of the humeral head in order to identify patients at a higher risk of screw cutout after open reduction internal fixation (ORIF).
Methods
A retrospective review was performed at an academic medical center of all patients who were 18 years or older who had sustained a proximal humerus fracture between 1/1/05 and 12/31/14 that was treated with ORIF and who had a preoperative shoulder CT. Ninety-four patients were included. Charts were reviewed for demographics and radiographs were reviewed for screw cutout. A standardized method was devised to measure the center of the humeral head thickness.
Results
Seventeen patients developed screw cutout (17.7%). The mean humeral head thickness was significantly smaller on the axial (18mm vs 21mm; p=0.0031), coronal (18mm vs 21mm; p=0.0084) and sagittal sections (18mm vs 21mm; p=0.0033) in the patients who experienced screw cutout. When the smallest of the three measurements for each patient was analyzed, the risk of cutout was markedly greater when the humeral head thickness was less than 20mm (25% vs 6%). Additionally, when the humeral head thickness was greater than 25mm the risk of cutout was reduced to zero. Low-energy injury was associated with a lower risk of cutout, while age, sex and fracture classification were not independent predictors of cutout on multivariate logistic regression.
Conclusions
In patients with proximal humerus fractures where a preoperative CT scan is available, calculating the thickness of the center of the humeral head may provide valuable information to both the surgeon and the patient in preoperative planning and counselling. A smaller thickness of the center of the humeral head on preoperative CT is predictive of screw cutout following locked plating of proximal humerus fractures. A measurement of 25mm in any one plane is highly protective against cutout, however extreme caution and consideration of supplemental fixation methods should be taken when the measurements in all planes are less than 15mm. This information may be helpful in counseling patients regarding the possibility of postoperative screw cutout.
... Lack of a medial cortical support was found to be another significant predictor of the failure in the previous study. Screw cutout or perforation of the humeral head into the glenohumeral joint occurred with a rate of 7.5% and was the most common reason for early revision surgery in the previous review [3][4][5][6][9][10][11][12]. ...
Background:
Complications following locking plate fixation in proximal humeral fractures often related to malposition plates and inadequate screw fixation. However, literature did not define the best anatomical reference point for plate positioning. We conducted a study to assess the occurrence of subacromial impingement and screw perforation with two anatomical reference points for proximal humeral plate positioning.
Method:
Sixty shoulders of 30 cadavers were dissected, and proximal humeral locking plate was placed in two different levels in the coronal plane of the upper tip of plate: (1) the proximal portion of bicipital groove group and (2) the most prominent of lesser tuberosity group. Subacromial impingement during passive forward elevation and screw perforation were assessed in relation to the plate positioning.
Results:
No subacromial impingement during passive motion contacted to the plate in both groups. The calcar screw perforation rate was significantly lower in the proximal portion of the bicipital groove group (2 of 60 specimens, 3.33%) than the most prominent of lesser tuberosity group (52 of 60 specimens, 86.67%). The most proximal screws of the plate were no humeral head perforation in all specimens.
Conclusion:
Our study would suggest that two anatomical reference points could be used to be the landmark to avoid the subacromial impingement and the most proximal screw perforation. However, the placement of the locking plate using the proximal portion of bicipital groove reference is better for calcar screw insertion.
... Some authors attribute the high complication rates to surgical technique, positing that exceptional vigilance is required when estimating the appropriate number and length of screws used for fixation [8,9]. Previous biomechanical cadaver studies suggest that screw pullout strength increases substantially when screws are positioned such that the tips reside in subchondral bone; these results guide current practice to target screw purchase between 5 and 8 mm from the articular margin [8,12,13]. However, high rates of screw perforation suggests that a greater interval between the screw and the subchondral bone may be necessary to mitigate the risk of screw advancement and injury to the articular surface. ...
... A rigid foam substrate (30 pcf open cell foam block, model 1522-525, Sawbones, Vashon Island WA) model with porosity comparable to that of osteoporotic trabecular bone was used to test screw pullout at burial depths equivalent to 8 mm, 11 mm and 14 mm from the joint surface. We utilized a fourth generation composite proximal humerus (Sawbones), to establish the burial depth the 60 mm screws would be subjected to when inserted through the right proximal hole of the PHILOS locking plate which is referenced as section A [1,12], or screw hole # 1 [13]. ...
... However, achieving adequate screw purchase by positioning screw tips in close proximity to the subchondral bone has been advocated as well [3,4,8]. Some authors argue that adequate screw purchase, 5-8 mm from the articular margin, should be the surgical goal in order to avert secondary screw cutout [5,8,13,25]. ...
... In this study, a secondary perforation rate of 6% was observed. The perforation rates of other working groups varied between 6.8 and 57% [3,7,10,[23][24][25]. The exclusion of the primary perforations by the intra-operative 3D image converter with successive replacement of the screws with "near perforation" could explain the low rate. ...
... Similarly, in the present study, the overall complication rate of 18% is in the lower range compared with the complication rate of 14-50% described in the literature [3,10,[21][22][23][24][25][26][27][28]. Revision operations were necessary in 15% of the patients in this study. ...
... Measuring NSA is an adequate method for assessing the anatomical reduction of proximal humerus fractures in the post-operative course [30]. The results for the post-operative NSA (132.6° ± 9.0°) and the follow-up NSA (126.5° ± 9.2°) of the present study are comparable with the findings of other authors [24,[30][31][32][33]. The rate of secondary loss of reduction of 24.2% is comparable with the results of other work groups [3,9,34]. ...
Purpose:
The purpose of this study was to identify the rate of primary screw perforations after osteosynthesis of proximal humerus fractures with intra-operative 3D fluoroscopy and to analyse the rate of secondary screw perforations as well as complications, outcome, and revision surgeries after a minimum of 12 months.
Materials and methods:
Thirty-three patients (20 female, 13 male, median age 67 years, range 35-85 years) with displaced proximal humerus fractures were included. After reduction and fixation, an intra-operative 3D fluoroscopy was performed to evaluate primary screw perforations (PS) and screws with "near perforation" (nPS). These screws were changed intra-operatively. Patients were followed-up for a minimum of 12 months. Clinical and radiological parameters, such as secondary screw perforation, secondary loss of reduction, or functional outcome, were investigated.
Results:
In six patients (18.2%), humeral head screws were changed due to primary PS (n = 2) or nPS (n = 4) after the intra-operative 3D fluoroscopy. Follow-up revealed an adapted constant score (%CMS) of 76.2% after a mean follow-up of 17.7 months. Two secondary screw perforations were observed (6%). Loss of reduction was observed in eight patients (24.2%).
Conclusion:
The intra-operative 3D reveals a high rate of primary screw perforations or near perforations. Immediate change of these screws may lead to a lower rate of secondary screw perforations and, therefore, reduce post-operative complications.
... In fact tension band wiring was not used in any of the cases. Medial support screws have important contributions to the strength of the medial comminution and, also using of tension band wiring is recommended to neutralize the traction forces of rotator cuff when medial support is insufficient [24,29]. The non-union is another major complication in 3 or 4 -part humeral head fractures [17]. ...
Aim: Proximal humeral fractures are approximately 5% of all fractures and, %15-20 is displaced and unstable. By the introduction of locking plates there used to be a substantial rise in the osteosynthesis of the 3 and 4-part proxi-mal humeral fractures. But there is still a lack of consensus for the optimal treatment of these complex fractures. In this retrospective study, we aimed to evaluate the functional outcomes and prognostic factors of 3 and 4-part proximal humerus fractures treated with locking plate osteosynthesis in el-derly. Material and Method: 53 patients with displaced 3 and 4-part proximal humeral fractures treated with locking plate osteosynthesis between 2010 and 2015 were included. The fractures were classified according to Neer classification system. Outcomes were assessed by Constant-Murley scoring system (CMS), visual analog pain scale and plain radiographs. In reference to range of motion, forward elevation and abduction of the arm were measured.Results: No statistically significant differences found between the 3-part and 4-part fractures in CMS, forward elevation and, abduction (p>0.05). Pain was significantly higher in 4-part fractures (p=0.035). CMS, forward eleva-tion, and abduction were inversely correlated with age and delay in surgery. There was statistical significance between the patients had complications and those not in terms of CMS, forward elevation and, abduction (p=0.029, p=0.017 and p=0.024). Discussion: Functional outcomes of locking plate fixa-tion of proximal humerus fractures are associated with patient related fac-tors, fracture pattern, surgeon and, the implant. When indications are care-fully selected, locking plate osteosynthesis yield good outcomes in surgical treatment of 3 or 4-part proximal humerus fractures
... Neck-shaft angle is a means of evaluating proximal humerus displacement in the coronal plane [1,2]. It has been shown to be useful in planning arthroplasty [3] and osteotomy [4,5], and in evaluating results after osteosynthesis [6][7][8]. Its value is approximately 135º [9] and is measured on true anterior-posterior (AP) radiographs [6,7]. ...
... It has been shown to be useful in planning arthroplasty [3] and osteotomy [4,5], and in evaluating results after osteosynthesis [6][7][8]. Its value is approximately 135º [9] and is measured on true anterior-posterior (AP) radiographs [6,7]. ...
Background:
Two recent experimental studies evaluated the influence of glenoid version on neck-shaft angle, with conflicting results. However, there have been no clinical studies of whether this angle varies in different shoulder positions. The present study aimed to determine whether glenoid version affects neck-shaft angle on standard radiographs in patients with complaints of shoulder pain.
Hypothesis:
Glenoid version does not affect neck-shaft angle.
Materials and methods:
A prospective study was conducted in selected patients with shoulder pain. Three true anterior-posterior radiographic views were obtained: in neutral rotation, 30° external rotation, and internal rotation with patient́s arm in a sling. The X-rays were evaluated by three shoulder and elbow surgeons. Inter- and intra-observer reliability was evaluated by intraclass correlation coefficient (ICC).
Results:
Neck-shaft angle on true AP view did not differ between neutral rotation and 30° external rotation: 132° ± 6° and 130° ± 9°, respectively (p>0.999). In internal rotation with the hand resting on the abdomen, neck-shaft angle was 145° ± 6°: i.e., significantly different (p<0.001) to the other two positions. Intra- and inter-observer correlation demonstrated excellent reliability.
Conclusions:
Radiographic neck-shaft angle was significantly different in internal rotation with the patient's arm in a sling, compared with views in neutral or 30° external rotation. Intra- and inter-observer correlation showed excellent reliability.
Level of evidence:
II, comparative prospective study.
... 2,3 In fractures of the proximal humerus, the angle is useful to evaluate the radiographic results of surgical treatment. 4,7,8 The angle, which is approximately 135 , 5 is measured on radiographs in true anteroposterior (AP) view. 4,8 However, joint pain or stiffness can make it impossible to correctly position the arm. ...
... 4,7,8 The angle, which is approximately 135 , 5 is measured on radiographs in true anteroposterior (AP) view. 4,8 However, joint pain or stiffness can make it impossible to correctly position the arm. In addition, variations between different image acquisition protocols, possible technical errors, and anatomic variations can impede the acquisition of standardized images in the true AP view. ...
... 2,3 The evaluation of fracture reduction quality is another use for this angle. 4,7,8 Given the possible technical and positioning variations resulting from the different image acquisition protocols or the condition of the patient, it is important to determine whether measurements of this angle are altered according to the degree of rotation of the arm. ...
Background:
The head-shaft angle is used to plan osteotomies and arthroplasties and to assess the radiographic outcomes of surgical treatment for proximal humerus fractures. There are no published data showing whether different degrees of arm rotation interfere with the evaluation of this angle.
Methods:
Eighteen humeri from adult cadavers were used. Radiographs were taken with the specimens initially placed in a true anteroposterior position and then subsequently positioned with internal and external rotations of 10°, 20°, and 30°. All radiographs were evaluated by 3 shoulder and elbow surgeons at 2 different times 3 months apart. The head-shaft angle was measured using a picture archiving and communication system.
Results:
For the humerus in the neutral position, the head-shaft angle was 137° ± 4°. With the anatomic specimen positioned with increasing external and internal rotations, there was a maximum difference of 2° compared with the value observed in the neutral position, which was not a significant difference (P = .911). Measurements of the head-shaft angle showed a good interobserver correlation coefficient, with a value of 0.788 (0.728-0.839) for all measurements. The intraobserver correlation coefficient ranged from moderate to excellent (0.536-0.938).
Conclusion:
The head-shaft angle did not change significantly with varying degrees of humeral rotation. The interobserver correlation coefficient showed good reliability, and the intraobserver correlation was moderate to excellent.
