European Journal of Cardiovascular Medicine

Fractures of the proximal humerus account for 4–5% of all fractures and are particularly common in elderly populations, following only hip and distal radius fractures in frequency [1]. These injuries are increasingly seen in younger patients due to high-energy trauma, such as road traffic accidents [2]. While conservative management is often sufficient for minimally displaced fractures, displaced fractures, particularly of Neer’s Type 2 and 3, frequently require surgical intervention for optimal recovery [3].

The PHILOS plate has emerged as a reliable solution for internal fixation of proximal humerus fractures, especially in osteoporotic bone, providing angular stability and facilitating early mobilization [4]. However, patient-specific factors such as smoking may alter surgical outcomes. Smoking has been documented to impair bone metabolism, reduce vascularity, and delay fracture healing through mechanisms involving hypoxia, vasoconstriction, and inhibition of osteoblast activity [5, 6].

Although numerous studies have evaluated surgical approaches and fixation methods for proximal humerus fractures, few have addressed the influence of smoking on postoperative recovery. This study aims to determine whether smoking significantly affects functional and radiological outcomes after PHILOS plate fixation in Neer’s Type 2 and 3 fractures.

Study Design and Setting:
A prospective, observational study was conducted at Dr. Bhim Rao Ambedkar Memorial Hospital, Raipur, from February 2022 to September 2022. Institutional ethical clearance and informed consent from all participants were obtained.

Sample Size and Grouping:
Twenty-two patients were included (15 males, 7 females), aged 30–70 years. They were divided into two groups: smokers (n=14) and non-smokers (n=8), based on self-reported smoking history of ≥1 cigarette/day for over 1 year.

Inclusion Criteria:

• Age 18–65 years
• Neer’s Type 2 or 3 proximal humerus fractures
• Closed fractures
• Surgery within 3 weeks of trauma

Exclusion Criteria:

• Open fractures
• Pathological fractures
• Bilateral fractures
• Neurological involvement
• Patients unfit for surgery

Surgical Procedure:
All patients underwent open reduction and internal fixation with PHILOS plates via either deltopectoral or deltoid split approach. Surgical approach was chosen based on fracture configuration and surgeon preference.

Postoperative Rehabilitation:
Standardized physiotherapy protocols were initiated postoperatively. Functional recovery was monitored using the Constant-Murley Score at 3, 12, and 24 weeks.

Radiological Evaluation:
Radiographs were taken at each follow-up to assess:

• Head-shaft angle (acceptable range: 125°–150°)
• Tuberosity height (8–10 mm from head)
• Callus formation
• Evidence of implant-related complications

Statistical Analysis:
Data were analyzed using SPSS v26. Continuous variables were compared using independent t-tests, and categorical variables using Chi-square or Fisher’s exact test. A p-value <0.05 was considered statistically significant.

A total of 22 patients who underwent PHILOS plate fixation for Neer’s Type 2 or Type 3 proximal humerus fractures were included in the study. Among them, 14 were categorized as smokers and 8 as non-smokers. The results were analyzed in terms of demographic characteristics, functional outcomes using the Constant-Murley score, radiological union, and complication rates.

The baseline characteristics between smokers and non-smokers were comparable, with no statistically significant differences observed. The mean age in the smoker group was 51.2 ± 8.7 years, while in non-smokers it was 50.4 ± 9.2 years (p = 0.78). Males were predominant in both groups (71.4% in smokers vs. 62.5% in non-smokers, p = 0.63). The distribution of Neer Type 2 fractures was slightly higher among smokers (57.1%) than non-smokers (50%), but the difference was not statistically significant (p = 0.72). Similarly, the choice of surgical approach (deltopectoral) was similar between groups (57.1% in smokers vs. 62.5% in non-smokers, p = 0.80). These findings are summarized in Table 1.

Functional recovery, assessed via the Constant-Murley score at 3, 12, and 24 weeks postoperatively, demonstrated a consistent trend of poorer outcomes among smokers. At 3 weeks, the mean score for smokers was 38.4 ± 6.5, compared to 42.1 ± 5.2 in non-smokers, though this was not statistically significant (p = 0.12). However, at 12 weeks, the difference became significant (59.7 ± 7.8 vs. 68.3 ± 5.7; p = 0.016), and by 24 weeks, smokers continued to lag with a mean score of 71.2 ± 8.5 compared to 81.3 ± 6.7 in non-smokers (p = 0.023), indicating a significantly slower functional recovery in smokers (Table 2).

By the 12-week follow-up, radiological union was observed in all non-smokers (8/8; 100%) and in 11 of 14 smokers (78.6%). The difference was statistically significant (p = 0.041), highlighting a higher rate of delayed bone healing among smokers (Table 3).

Smokers exhibited a higher complication rate overall compared to non-smokers, although the individual differences were not statistically significant. Delayed union occurred in 3 smokers (21.4%) and none in the non-smoker group (p = 0.09). Implant back-out was seen in 2 smokers (14.3%) and no non-smokers (p = 0.17). One smoker (7.1%) developed a superficial infection, while no infections were recorded among non-smokers (p = 0.33). These findings are summarized in Table 4.

Table 1: Demographics and Baseline Characteristics

Table 2: Functional Outcome (Constant Score)

Table 3: Radiological Union by 12 Weeks

Table 4: Complications

This study revealed that smoking significantly impairs both functional and radiological outcomes in patients undergoing PHILOS plate fixation for Neer’s Type 2 and 3 proximal humerus fractures. At 6 months, the mean Constant score was lower in smokers, and the rate of radiological union was delayed.

These findings align with previous orthopedic literature, which has shown impaired fracture healing in smokers across various anatomical sites [7, 8]. In particular, Scolaro et al. emphasized the increased risk of delayed union and non-union in smokers with humeral fractures [9].

The underlying mechanisms are well documented. Nicotine induces vasoconstriction, carbon monoxide causes tissue hypoxia, and reactive oxygen species impair osteoblast differentiation [10, 11]. Sørensen et al. also demonstrated that smoking increases postoperative complication rates and impairs collagen synthesis during wound healing [12-15].

While the sample size of this study is limited, the differences in Constant scores and union rates are statistically significant, suggesting a clinically relevant impact. Notably, the complication rates, although higher in smokers, did not reach statistical significance—possibly due to the small sample.

The use of a standardized rehabilitation protocol and consistent implant selection (PHILOS plate) strengthens internal validity. However, limitations include the non-randomized design and reliance on self-reported smoking status.

Future multicenter trials with larger cohorts could validate these findings and explore dose-response relationships, smoking cessation interventions, and the role of adjunct therapies such as bone stimulators or vitamin D supplementation.

Smoking is associated with significantly poorer functional and radiological outcomes following PHILOS plate fixation for Neer’s Type 2 and 3 proximal humerus fractures. Surgeons should consider smoking history during preoperative risk assessment and counsel patients regarding smoking cessation to optimize healing and reduce complication rates.

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