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 Table of Contents  
ORIGINAL ARTICLE
Year : 2017  |  Volume : 9  |  Issue : 2  |  Page : 99-105

Comparison of open reduction internal fixation with proximal humerus interlocking system and close reduction and pinning with K-wire in proximal humeral fracture


1 Department of Orthopedics, Jhalawar Medical College, Jhalawar, Rajasthan, India
2 Department of Orthopaedics, S.N. Medical College, Jodhpur, Rajasthan, India
3 Department of Orthopedics, JLN Medical College, Ajmer, Rajasthan, India
4 Department of Pediatric Dentistry, GDC, Jaipur, Rajasthan, India

Date of Web Publication14-Dec-2017

Correspondence Address:
Dr. Akshat Vijay
B-202 Shivam Enclave, Bajrang Nagar, Near Police Lines, Kota - 324 001, Rajasthan
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jotr.jotr_11_17

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  Abstract 


Introduction: Fracture of the proximal humerus represents the second most common fracture in upper extremity. The indications of surgery continue to expand due to improvement in internal fixation techniques. Aim: This study aimed to compare the result of open reduction internal fixation with proximal humerus interlocking system and close reduction and pinning with K-wire in these fractures. Materials and Methods: This study included 48 cases which were divided into two groups by randomized controlled trial type of study design, 24 patients (Group A) were operated with proximal humerus internal locking system (PHILOS) and 24 patients (Group B) with percutaneous K-wire fixation. All the 48 patients were followed up for a mean duration of 11 months. Final evaluation was done according to Neer's (1970) criteria. Results: All fractures united with an average of 10.34 weeks. Union time between the groups was statistically insignificant. In Group A, 83.33% of cases had favorable results against 50.0% of Group B and difference was significant. In Group A, mean Neer's score was 86.0 and in Group B it was 77.7 and difference was significant. In Group A, mean Neer's score for range of motion (ROM) was 20.75 and in Group B it was 17.25 and difference was significant. Ten complications (subacromial impingement-1, screw perforation-1, infection-1, malunion-2, stiff shoulder-3, and pain in shoulder-2) were seen in six patients (25%) treated with PHILOS and 17 complications (K-wire migration-2, infection-2, malunion-4, stiff shoulder-6, and pain in shoulder-3) were seen in 10 patients (41.1%) fixed with K-wire. Conclusion: In patients of 2-part and 3-part displaced proximal humerus fractures, results are almost equivocal. However, mean Neer's score for ROM was significantly more in patients treated with PHILOS. In 4-part fracture and patients of age >50 years, results of PHILOS are significantly better than K-wire.

Keywords: Neer's score, proximal humerus interlocking system, stiff shoulder, subacromial impingement


How to cite this article:
Vijay A, Kumar M, Bhaskar S K, Rao B S, Gandhi M. Comparison of open reduction internal fixation with proximal humerus interlocking system and close reduction and pinning with K-wire in proximal humeral fracture. J Orthop Traumatol Rehabil 2017;9:99-105

How to cite this URL:
Vijay A, Kumar M, Bhaskar S K, Rao B S, Gandhi M. Comparison of open reduction internal fixation with proximal humerus interlocking system and close reduction and pinning with K-wire in proximal humeral fracture. J Orthop Traumatol Rehabil [serial online] 2017 [cited 2018 May 28];9:99-105. Available from: http://www.jotr.in/text.asp?2017/9/2/99/220754




  Introduction Top


Fracture of the proximal humerus represents the second most common fracture type in upper extremity. Three-fourth of the proximal humerus fracture occur in the elderly with osteoporosis following low-energy injury with incidence three times more often in women than in men.[1] The choice of treatment depends on the pattern of the fracture, the quality of the bone encountered, the patient's requirement, and the surgeon's familiarity with the procedures. The age of patient, physical activity, and medical fitness also largely influence the treatment options. Among various treatment options available, one is closed reduction and percutaneous K-wire fixation.[2] It has advantages of less blood loss, lower risk of neurovascular complications, and less interference with glenohumeral joint motion.[3],[4] However, disadvantages of a prolonged immobilization which lead to the stiffness of shoulder joint [5],[6] and anatomical reduction are usually not achieved. Open reduction and internal fixation (ORIF) with plating is another method to achieve anatomical, stable, and secure reduction with immediate mobilization. The proximal humerus interlocking system is anatomically contoured and the threaded screw heads are locked into the threaded plate holes to prevent screw toggle, slide and pull out, and give angular stability. These plates have a low profile and hence the danger of postoperative soft tissue impingement syndrome is very less.

The aim of our study was to compare the results of open reduction internal fixation with proximal humerus interlocking system and close reduction and pinning with K-wire in proximal humeral fractures.


  Materials and Methods Top


The prospective study included 48 cases of fracture of proximal humerus admitted in a tertiary care center from January 1, 2014 to September 1, 2015. Patients were divided into two groups by randomized controlled trial type of study design (using block randomization sealed envelope technique), 24 patients (Group A) were operated with proximal humerus internal locking system (PHILOS) and 24 patients (Group B) with percutaneous K-wire fixation in a prospective series of displaced proximal humerus fractures. All these 48 patients were followed up for a mean duration of 11 months.

Permission was obtained from the ethical committee in accordance with 1975, Helsinki Declaration before starting the research. Informed consent was obtained from all the patients.

Inclusion and exclusion criteria

All patients with displaced fracture (>1 cm of separation or >45° angulation) of proximal humerus were included with exclusion of; patients <18 years of age, comminuted fractures of head of humerus with significant bone loss suggesting insufficient screw purchase and thus preferred for humeral arthroplasty, isolated greater tuberosity fracture in Neer's 2-part fracture, fracture dislocation, pathologic fractures from primary or metastatic tumors, and patients with nonunion/malunion and open fractures. Fractures were classified according to the Neer's description. Final results were evaluated by Neer's criteria.[7]

In Group A, surgery was performed through the deltopectoral (anterior)[8],[9] approach under general anesthesia in beach chair position with all aseptic precautions. All patients received latest generation of anatomically precontoured proximal humerus locking compression plate. The locking plate was applied to anterolateral aspect of proximal humerus 2 mm posterior to bicipital groove, approximately 0.5–1 cm below the tip of the greater tuberosity to limit subacromial plate impingement. Rotator cuff, capsule, and subscapularis muscle tears/avulsions were repaired. Whenever tuberosities were found fractured, they were fixed to the plate using nonabsorbable sutures. Pendulum exercises with full range of elbow, wrist, and finger movements were started 48 h after operation. Active assisted, forward elevation, and external and internal rotation of shoulder were encouraged from the 7th day. Stitches were removed on the 12th day and step ladder was started on the 3rd week.

In Group B, after giving general anesthesia and placing the patient in beach chair position with all aseptic precautions, we adopted the method of Millet et al.[10] and Rowles and McGrory [11] for deciding the safe starting point for the proximal lateral pins and the end point for the greater tuberosity pins. The starting point for the proximal lateral pin was double the distance from the superior most aspect of the humeral head to the inferior most aspect of the humeral head, and the end point for the greater tuberosity pin was >2 cm inferior to the inferior most margin of the humeral head.

For 2-part fractures, the 2.0 mm K-wire was then positioned at this location and confirmed with a fluoroscopic image. While holding the reduction, K-wire was drilled up into the humeral head until the K-wire tip was just beneath the articular surface. A second K-wire was drilled parallel to the first one so that the two K-wires were spread apart (ideally, 1.5–2.0 cm) in the humeral head. Finally, a third K-wire was placed into the humeral head from an anterior direction. If necessary, a fourth K-wire was added from an anterior direction for additional stability.

In 3-part fractures, after aligning the shaft with the articular segment as described above with three or four K-wires, two K-wires were placed from the greater tuberosity into the humeral head in antegrade orientation.

In 4-part fractures, after achieving reduction and fixation of the humeral shaft and the greater tuberosity to the articular segment as described above, the lesser tuberosity fragment was reduced by internally rotating the arm and fixing with another K-wire.

In all patients, final biplanar images confirmed reduction in both the anteroposterior and axillary planes.

The arm was immobilized in an arm pouch sling for the next 6 weeks and mobilization exercises were restricted during this duration. K-wires were removed at 6 weeks after clinically and radiologically assessing for stability of fixation, if reduction was found to be insecure and then K-wires were left, and patients were followed up for another 2 weeks.

The patients were followed up on an outpatient department basis at 2 weeks postoperatively till 1 month, and then monthly for 6 months and 3 months till the end of the 1st year and yearly thereafter [Figure 1]a and [Figure 1]b and [Figure 2]a and [Figure 2]b. Final follow-up and evaluation was done according to Neer's (1970) criteria.[7]
Figure 1: Case 1-43-year-old male (a) radiographs, (b) clinical photographs

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Figure 2: Case 2-36-year-old male (a) radiographs, (b) clinical photographs

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The data were checked for normal distribution with the help of Kolmogorov–Smirnov test with Lilliefors correction and Shapiro–Wilk test and it was found that the data were normally distributed. Therefore, parametric tests were applied for evaluation of results. Comparison between PHILOS group and K-wire group was done by unpaired t-test while Fisher's exact test was used for categorical data.


  Results Top


In our study, no significant difference was found between both groups witn regards to fracture pattern (using Fisher's exact test) (P > 0.05).

Out of the 48 patients, 28 (58.33%) were female and 20 (41.67%) were male showing female predominance, most of them were right handed and the average age was 51.29 years, with youngest patient of 21 years and the oldest one of 77 years. Fall on ground was the most common mode of injury with 28 (58.33%) patients, majority of them were around 50 years of age, depicting the role of osteoporosis in causing these fractures with minor trauma and 16 (33.33%) patients were injured due to road traffic accidents. Average duration of follow-up was 11 months. All fractures united with an average of 10.34 weeks. In Group A, 83.33% of cases had favorable results as against 50.0% cases of Group B and difference between the groups was statistically significant (using Fisher's exact test) [Table 1].
Table 1: Comparison of results of operative procedure between groups

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Mean Neer's score and mean Neer's score for range of motion (ROM) in Group A was 86.0 and 20.75 while for Group B was 77.7 and 17.25, respectively. Difference between the groups was statistically significant (P = 0.0085 and P = 0.0001, respectively). Hence, better functional results and range of movement were achieved in patients who were operated with PHILOS as compared to those with K-wire [Figure 3].
Figure 3: Comparison of Neer's score between groups

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The difference between the groups was statistically significant in patients of age group >50 years and insignificant in age group <50 years. Hence in age group >50 years, better results were achieved in patients who were operated with PHILOS as compared to those with K-wire [Table 2].
Table 2: Comparison of results of different age groups between groups

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The difference between the groups was statistically significant in patients of 4-part fractures and insignificant in 2- and 3-part fractures. Thus, good results were achieved in patients of 4-part fractures in Group A as compared to Group B [Table 3].
Table 3: Comparison of results of different fracture patterns between groups

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In our study, ten complications were seen in six (25%) patients in Group A; restricted ROM was seen in three patients out of which two patients had varus malunion also. One patient had subacromial impingement thus causing restricted ROM in spite of all phases of physiotherapy. Two patients had complaints of pain till the final follow-up; among them, one had screw perforation into shoulder joint. Superficial infection developed in one patient for which the patient was again admitted and managed conservatively with intravenous (IV) antibiotics (ceftriaxone 1 g and amikacin 500 mg) and repeated dressings. Infection was controlled and plate was removed after union. In one patient, fracture was fixed in varus leading to decreased ROM and Neer's score at the final follow-up [Table 4] and [Figure 4]a, [Figure 4]b, [Figure 4]c, [Figure 4]d, [Figure 4]e.
Table 4: Complications in patients

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Figure 4: Complications, (a) fracture union with infection and active discharge from sinus, (b) fracture union with subacromial impingement and restricted range of motion, (c) fracture union with varus malunion and restricted range of motion, (d) fracture union with screw perforation and varus malunion, (e) fracture union with K-wire migration

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Seventeen complications were seen in ten (41.1%) patients in Group B; in two patients, pin tract infection developed for which the patient was admitted and repeated dressings with IV antibiotics (ceftriaxone 1 g and amikacin 500 mg) were given, infection was controlled without the need of removal of K-wires which were removed later after union. In two patients, medial migration of K-wire was seen leading to pain at the final follow-up, however no damage to neurovascular structure developed. Restricted ROM was seen in six patients; out of which four also had varus malunion concomitantly while one patient had complaint of pain at the final follow-up. The higher number of restricted ROM patients in K-wire group than PHILOS group shows the benefit of early mobilization among PHILOS patients due to more stable construct. Three patients had pain at the final follow-up; out of these, one had pin tract infection and one had restricted ROM also [Table 4] and [Figure 4]a, [Figure 4]b, [Figure 4]c, [Figure 4]d, [Figure 4]e.


  Discussion Top


Most of the undisplaced proximal humeral fractures can be treated conservatively. However, displaced fractures require surgical treatment for better outcomes. The treatment goal was to achieve a painless shoulder with full ROM. Many different fixation techniques such as nonabsorbable bone suture, tension band, K-wire, T-plate, intramedullary device, and hemiarthroplasty have been used for these difficult fractures. However, all the techniques have a persistent rate of mechanical failure and may increase the complication rates.[12]

In our study, the average age of patients was 51.29 years (ranging from 21 to 77), thus depicting the role of senile osteoporosis in causing these fractures, as has been mentioned by other authors.[13],[14] Fracture union has never been a problem in proximal humeral fracture management as had been mentioned in many studies [15],[16],[17],[18] due to cancellous nature of bone unless anatomical neck or articular part of humerus is involved, compromising bone of its blood supply. In our study, all fractures united successfully. There were no cases of delayed union or nonunion in our study. The average time for union (in weeks) was found to be 10.34 (ranging 7–18 weeks) and was unaffected by the modality of treatment used.

ORIF with PHILOS offers better anatomical reduction with more rigid fixation into the metaphyseal bone and consequently allows for earlier mobilization, which decreases postoperative stiffness. Another advantage of this technique is the ability to obtain a good reduction of the greater tuberosity. Hence, we had significantly more favorable results in Group A patients as compared to Group B patients. Higher Neer's score with better ROM was observed in patients of Group A as compared to Group B due to similar reasons. Several other authors [15],[16],[17],[18],[19],[20],[21],[22],[23],[24] have also obtained similar results [Table 5].
Table 5: Comparison of results of different studies

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Two- and three-part proximal humeral fractures have good results with both PHILOS and K-wires as compared to 4-part fractures, in which PHILOS had much better results than K-wires as it provides more rigid as well as stable construct and fixation of tuberosities with nonabsorbable sutures. Dolfi et al.[16] operated Type II, Type III, and Type IV fractures of proximal humerus using distally threaded dynamic hip screw guide pins, 2 mm K-wires, or 2.5 mm distally threaded Schantz pins. In their study, all patients with Neer's Type IV fractures did not respond to fixation and three had avascular necrosis (AVN), irrespective of the type of pin used. They concluded that stable fixation with early motion and subsequently good results can be obtained using percutaneous fixation in patients with Type II and Type III fractures; however, terminally threaded pins must be used and smooth K-wires must be avoided. Percutaneous fixation cannot be recommended in patients with Type IV fractures. In our study, patients of age group >50 years had better results when operated with PHILOS as compared with K-wires while no significant difference was observed in patients in the age group of <50 years. PHILOS has proximal locking screws which produce an angular stable construct to enhance the grip in osteoporotic bone and multi-fragment fractures. The screws alternately diverge and converge improving purchase in head and also increase the pullout strength. Shiva et al.[25] in their study also observed that the functional outcome of the patients who underwent K-wire fixation below the age of 60 years (5 patients) was 81.6 and more than 60 years of age (6 patients) was 66.8. Similarly, functional outcome of plating below 60 years (10 patients) of age was 85.3 and more than 60 years (5 patients) of age was 72.8.

Seven out of ten complications in Group A were due to inappropriate plate placement and improper reduction of greater tuberosity. Proper reduction of the greater tuberosity and other fragments before applying plate would have prevented impingement. Satisfactory reduction of the fracture fragments with proper positioning of the plate and screw perforation should be checked under image control intraoperatively for better results. Medial comminution should be well attended by fixation with additional screws inferomedially. Early rehabilitation was paramount for obtaining good range of movements and prevention of stiffness. Maintenance of medial periosteal hinge and careful surgical dissection prevents damage to the posteromedial vessels at posteromedial neck of humerus, thus decreasing the incidence of AVN in follow-ups.

However in our study, overall results of K-wires were more unfavorable than studies by Smejkal et al.[26] and Jaberg et al.,[27] as mean age of patients in our study was 51 years, thus more elder patients were present in our study having poor bone quality and more comminution at fracture site which caused more loss of reduction and K-wire migration. Furthermore, the K-wires used in our study were neither threaded nor have we used terminally threaded Schanz screw. Also, transosseous sutures and screws for fixation of tuberosities were not used in our study.

In the present study, average follow-up was 11 months (range: 6–18 months). Long duration of follow-up gives a broader spectrum of complication rates which appears late after operative interventions such as secondary osteoarthritis and osteonecrosis of proximal humerus. As compared to other studies,[13],[28] the present study is lacking long duration of follow-up, hence affecting complication rates as mentioned in them.


  Conclusion Top


By the analysis of the data collected in the present study, it was found that ORIF with PHILOS is a better choice for 4-part proximal humeral fractures in elderly patients. To achieve better results, early physiotherapy is must which can be done by stable fixation with PHILOS which provides more stable construct with anatomical reduction of tuberosities.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Acknowledgments

We are grateful to Dr. S. K. Bhaskar and Dr. B. S. Rao for their help in conducting the study and manuscript preparation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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