Correlation between chronic pain, disability, and psychological factors (depression and anxiety) after surgery for acute orthopedic trauma

Abstract

BACKGROUND

The occurrence of chronic pain and disability after acute orthopedic trauma is significantly correlated with psychological factors, particularly depression and anxiety. As such, assessment of these factors is crucial for postoperative rehabilitation.

AIM

To investigate the correlation between chronic pain, disability, and psychological factors (depression and anxiety) after acute orthopedic trauma surgery.

METHODS

Data from 120 patients, who underwent surgery for acute orthopedic trauma at Xi’an Traditional Chinese Medicine Hospital (Shaanxi Province, China) between June 2022 and June 2024, were retrospectively analyzed. Basic information and postoperative pain metrics [visual analog scale (VAS)], disability rating index (DRI), Hamilton anxiety rating scale (HAMA) and Hamilton depression rating scale (HAMD) were collected from electronic medical records. Pearson’s correlation analysis was used to examine associations between chronic pain VAS, DRI, HAMD, and HAMA scores.

RESULTS

Among the 120 patients [79 (65.8%) males and 41 (34.2%) females], postoperative VAS scores were significantly associated with HAMD and HAMA scores, with correlation coefficients of 0.625 (P = 0.027) and 0.568 (P < 0.001), respectively. Postoperative DRI scores were also significantly associated with HAMD and HAMA scores, with correlation coefficients of 0.683 and 0.557, respectively (both P < 0.001).

CONCLUSION

Chronic pain and disability after surgery for acute orthopedic trauma are significantly correlated with psychological factors (depression and anxiety). Multidisciplinary teams should integrate mental health services to improve patient outcomes.

Key Words: Acute orthopedic trauma; Chronic pain; Disability; Depression; Anxiety; Correlation

Core Tip: After treatment for acute orthopedic trauma, the occurrence of chronic pain and disability is significantly correlated with psychological factors, particularly depression and anxiety. As such, psychological assessment is crucial for rehabilitation. This study investigated the correlation among chronic pain, disability, and psychological factors (depression and anxiety) in patients who underwent surgery for acute orthopedic trauma. Postoperative visual analog scale scores were significantly associated with Hamilton depression rating scale and anxiety scale scores, with correlation coefficients of 0.625 (P = 0.027) and 0.568 (P < 0.001), respectively, as were postoperative Disability Rating Index scores, with correlation coefficients of 0.683 and 0.557, respectively (both P < 0.001).

INTRODUCTION

Acute orthopedic trauma refers to injuries to the bones and/or surrounding soft tissue(s) caused by external factors, and typically include fractures, sprains, and dislocations. This has become a significant public health issue that has led to long-term health problems. According to the World Health Organization, trauma is one of the leading causes of death and disability worldwide. Trauma not only severely affects individual health but also imposes substantial burdens on societies and economies[1]. Fractures are among the most common types of acute orthopedic trauma. The management of fractures typically requires comprehensive consideration of factors such as injury severity, patient age, and pre-injury health status. For high-energy injuries, such as tibial plateau fractures, a detailed assessment of soft tissue damage is usually required to develop a surgical management strategy[2]. Additionally, femoral fractures after hip-replacement surgery are a common complication encountered in emergency departments, and their diagnosis and management are dependent on imaging results[3]. Among sports-related orthopedic injuries, elbow injuries are particularly common among young athletes. These injuries are often associated with throwing motions and the volume of physical activity, and require special attention for injuries to the growth plates and/or other bony structures[4]. Additionally, ankle sprains are highly prevalent among military personnel, and studies have reported that ankle sprains are often accompanied by fractures and have high recurrence rates[5]. Systematic management is crucial in pediatric orthopedic injuries. The unique anatomical structures and injury patterns of children and their bones require special management strategies to prevent acute and late complications[6]. Multidisciplinary collaboration is key to the prevention and treatment of post-traumatic infections, especially when dealing with deep wounds and/or extensive injuries to the bones and joints[7].

China, a populous country, has an annual incidence rate of acute orthopedic trauma ranging from 1.2 to 1.5 per 1000 individuals, making it the leading cause of disability among those 20-50 years of age in the working-age population. Although modern orthopedic surgical techniques have significantly improved the efficiency of wound healing, infections and sepsis-related fractures remain significant causes of morbidity and mortality in patients who experience trauma[8]. In China, hospitalization and in-hospital mortality rates for traumatic fractures are relatively high, primarily due to falls and motor vehicle collisions[9]. In particular, individuals who experience hip fractures have the highest hospitalization rates, and in-hospital mortality rates associated with motor vehicle collisions are the highest[9]. Although orthopedic trauma can lead to significant pain, the requisite surgeries to address these injuries can result in prolonged postoperative pain[10,11]. Chronic postsurgical pain can be a negative consequence of surgery and affects up to 50% of patients[12]. The incidence of acute orthopedic trauma is increasing annually with the increase in motor vehicle and industrial activities. Studies have shown that postoperative chronic pain and primary disabilities (such as limited mobility) significantly affect the quality of life of those affected[13-15]. Chronic pain is defined as pain lasting > 3 months and is usually accompanied by physical dysfunction and mental health problems. Orthopedic procedures, including bone fracture repair, amputation, limb salvage, and joint replacement, often lead to moderate-to-severe postoperative pain in as many as 90% of patients, with the risk for acute pain developing into chronic pain if not properly controlled, frequently lasting for multiple years[10,16]. At the neurobiological level, chronic pain after orthopedic trauma is closely associated with psychological factors. Studies have shown that psychological factors, such as depression and anxiety, can significantly influence postoperative pain outcomes[17]. One study showed that patients with chronic musculoskeletal pain may experience changes in the structure and function of the prefrontal cortex after conservative treatment. These changes include a shift from affective to sensory-discriminative brain activity, as well as normalization of resting-state networks and functional connectivity of the amygdala[18]. In addition, studies have found a reduction in gray matter volume in some areas of the brain in patients with osteoarthritis (OA), and this change may be related to the neuropathological components of OA pain. These studies highlight the complex relationship between OA pain and brain anatomy and the importance of adaptive changes in the brain to pain perception[19]. Psychological factors, therefore, play an important role in the occurrence and progression of chronic pain, further exacerbating the experience of pain by influencing brain structure and function. These findings provide new insights into the neurobiological mechanisms underlying pain.

In recent years, pain tolerance has been shown to be affected by numerous health and psychological factors in both healthy individuals and patients with chronic pain such as fibromyalgia[20]. Patients with depression frequently report experiencing chronic pain, and the reverse is true for psychosocial factors common to both conditions[21]. In contrast, chronic pain can exacerbate existing psychological problems and cause new issues[22]. The two-way relationship between chronic pain and mental health emphasizes the importance of simultaneously addressing both physical and psychological aspects of recovery[23]. Numerous neuroimaging studies have reported a link between prefrontal cortex structure and impulsivity, and this neuroplastic change may be the neurobiological basis of chronic pain[24]. Although anxiety and depressive symptoms, which are common among patients awaiting total knee arthroplasty, significantly decrease postoperatively, these patients often report lower satisfaction levels than those without preoperative psychological comorbidities[25]. Studies have demonstrated significant associations among pain severity, disability, and emotional distress in individuals with chronic pain[26]. Research indicates that psychological factors, such as anxiety, depression, and distressing thoughts, significantly influence the intensity and duration of postoperative pain[27]. For example, distressing thoughts are significant predictors of postoperative pain and disability, highlighting the crucial role of psychological factors in the recovery process[28]. Therefore, in the treatment of patients who experience orthopedic trauma, identifying and managing these psychological factors can help improve postoperative pain management and functional recovery.

The visual analog scale (VAS), a validated tool, is a straightforward and commonly used method for assessing changes in pain intensity[29,30]. In this study, the VAS was used to evaluate postoperative chronic pain. The disability rating index (DRI) is a self-administered 12-item VAS-based questionnaire that assesses patients’ self-rated disabilities. This measure was selected because it focuses on “gross body movements” rather than specific joints or body segments, thus facilitating the assessment of patients with various lower limb fractures[31]. Accordingly, this study used the DRI to assess disability in patients after surgery for acute orthopedic trauma. The Hamilton anxiety rating scale (HAMA) and Hamilton depression rating scale (HAMD) Scales are commonly used clinical psychiatric assessment tools for individuals with anxiety and depression[32,33]. To clarify anxiety and depression in the 2 groups in this study, the HAMA and HAMD Scales were used to investigate and evaluate levels of anxiety and depression.

The present study aimed to investigate the correlation between chronic pain, degree of disability, depression, and anxiety after surgery for acute orthopedic trauma to provide an important basis for improving the quality of postoperative rehabilitation, optimizing treatment strategies, and enhancing the specificity of psychological interventions.

MATERIALS AND METHODS

Study design and participants

This retrospective study included data from 120 individuals who underwent surgery for acute orthopedic trauma at Xi’an Traditional Chinese Medicine Hospital (Shaanxi Province, China) between June 2022 and June 2024.

Inclusion and exclusion criteria

Inclusion criteria: Acute (within 1-2 months) orthopedic injury (e.g., fracture, dislocation, or rupture)[34]; age ≥ 18 years; no pre-existing diagnosis of major depressive disorder or anxiety disorders (per Diagnostic and Statistical Manual of Depressive Disorders V criteria) as confirmed by psychiatric evaluation at enrollment; baseline HAMD score < 8 and HAMA score < 7 (subclinical levels) before injury; willingness to participate in all follow-up assessments; and complete baseline preoperative psychological and functional assessment and data collection.

Exclusion criteria: Current or lifetime history of schizophrenia spectrum disorders, bipolar disorder, substance-induced mood disorders, or major neurocognitive disorders; active psychotropic medication use (except short-term insomnia medications < 2 weeks); concurrent traumatic brain injury or spinal cord injury (ASIA impairment scale ≥ B), pre-injury chronic pain conditions (persisting > 3 months) or regular analgesic use; inability to complete Chinese-language questionnaires; and incomplete clinical data.

Ethics statement

This study was approved by the Ethics Committee of Xi’an Traditional Chinese Medicine Hospital. Given the retrospective nature of the study and use of anonymized patient data, the requirement for informed consent was waived.

Data collection

Data including patient age, sex, injury site, education level, marital status, smoking status, alcohol consumption, and intake of anesthetic and non-anesthetic analgesics were collected using information from the hospital’s electronic medical records system.

Observation indicators

Pain levels during the postoperative recovery period were assessed using the VAS, represented by a 100 mm horizontal line with “no pain” (0 points) on the left and “the worst pain imaginable” (100 points) on the right, with higher scores indicating increased pain level(s)[35]. The HAMD and HAMA Scales were used to assess postoperative depression and anxiety, with higher scores indicating more severe depression and anxiety[36,37]. The DRI, measured from 0 to 100 across 12 items, was recorded at each time point for patients without cognitive impairment[38].

This study also investigated the correlation between pain and disability and selected psychological indicators.

Statistical analysis

All statistical analyses were performed using SPSS version 26.0 (IBM Corp., Armonk, NY, United States). Enumerative data are expressed as percentage, and measurement data are expressed as mean ±SD. Pearson’s correlation analysis was used to examine the correlation between variables (VAS, DRI, HAMD, and HAMA). Differences with P < 0.05 were considered to be statistically significant.

RESULTS

General information

Data from 120 patients [79 male (65.8%), 41 (34.2%) female; 44.53 ± 10.12 years; median body mass index (BMI), 25 kg/m² (range 23 to 28 kg/m²⁾] were included in the analysis. Injuries in the cohort were distributed as follows: Motor vehicle collision [n = 28 (25.48%)], work-related injuries [n = 11 (10.01%)], sports-related injuries [n = 32 (29.12%)], falls [n = 31 (28.21%)], and others [n = 13 (11.83%)]. Five (4.55%) patients had a history of surgery. Regarding surgical sites, 43.3% (n = 52) were located in the lower extremities, ankles, or feet. Educational levels among the cohort were as follows: Primary school (13.3%), middle school (10.8%), high school (20.8%), and college or higher (55%). Regarding smoking history, 34.2% of patients smoked (n = 41), while 65.8% (n = 79) did not; 37.5% consumed alcohol (n = 45) and 62.5% (n = 75) did not. Twenty-one (17.5%) patients had comorbid hypertension. Regarding residence, 29 (24.2%) were from rural and 91 (75.8%) were from urban areas. Forty-seven (39.2%) participants were married, 52 (43.3%) were single, and 21 (17.5%) were divorced or widowed (Table 1). The types of injuries are reported in Figure 1.

Figure 1  Injury mechanism distribution of patients.

Table 1 Demographic and clinical characteristics.

Variable	Patients (n = 120)	Percentage (%)
Sex
Male	79	65.8
Female	41	34.2
Age (year)	44.53 ± 10.12	/
BMI (kg/m²)	25 (23-28)
Injury mechanism
Motor vehicle	28	25.48
Work	11	10.01
Sport	32	29.12
Fall	31	28.21
Other	13	11.83
Prior post-injury surgery	5	4.55
Surgery site
Other sites	68	56.7
Lower leg, ankle, or foot	52	43.3
Education
Primary	16	13.3
Secondary	13	10.8
Senior high school	25	20.8
College or above	66	55
History of smoking
Yes	41	34.2
No	79	65.8
History of drinking
Yes	45	37.5
No	75	62.5
Complicated with hypertension
Yes	21	17.5
No	99	82.5
Residence
Rural	29	24.2
Urban	91	75.8
Marital status
Married	47	39.2
Single	52	43.3
Divorced/widowed	21	17.5

BMI: Body mass index.

Postoperative chronic pain score

After surgery for acute orthopedic trauma, the mean VAS pain intensity score among the patients was 64.8 ± 21.7, with 16 (13.3%), 25 (20.8%), and 79 (65.9%) patients scoring ≤ 30, 31-60, and 61-100, respectively (Figure 2).

Figure 2 Visual analog scale distribution of patients. VAS: Visual analog scale.

Postoperative DRI score

After surgery for acute orthopedic trauma, the mean total DRI score was 47.8 ± 21.1. The specific score distribution of the 12 daily physical activities addressed in the DRI is reported in Figure 3.

Figure 3 Distribution of disability rating index scores after surgery. DRI: Disability rating index.

Postoperative psychological status

After surgery for acute orthopedic trauma, the mean total HAMD and HAMA scores of patients were 21.65 ± 3.31 and 20.54 ± 3.68, respectively (Figure 4).

Figure 4 Hamilton anxiety rating scale and Hamilton depression rating scale scores. HAMA: Hamilton anxiety rating scale; HAMD: Hamilton depression rating scale.

Correlation between chronic pain and psychological status

Pearson’s correlation analysis revealed that postoperative chronic pain was significantly correlated with psychological status (anxiety and depression). The correlation coefficients between the VAS and HAMD and HAMA scores were 0.625 and 0.568, respectively, both of which were statistically significant (P = 0.027 and P < 0.001; Table 2).

Table 2 Correlation between postoperative chronic pain and psychological status.

Psychological status	VAS
	r value	P value
HAMD	0.625	0.027
HAMA	0.568	< 0.001

VAS: Visual analog scale; HAMA: Hamilton anxiety rating scale; HAMD: Hamilton depression rating scale.

Correlation between postoperative disability and psychological status

Pearson’s correlation analysis revealed that postoperative disability significantly correlated with psychological status (anxiety and depression). The correlation coefficients between the DRI and HAMD and HAMA were 0.683 and 0.557, respectively, both of which were statistically significant (P < 0.001 and P < 0.001; Table 3).

Table 3 Correlation between postoperative disability and psychological status.

Psychological status	DRI
	r value	P value
HAMD	0.683	< 0.001
HAMA	0.557	< 0.001

DRI: Disability rating index; HAMA: Hamilton anxiety rating scale; HAMD: Hamilton depression rating scale.

DISCUSSION

A recent meta-analysis supported various components of the fear-avoidance model in patients with chronic pain and found strong associations between fear of pain, pain catastrophizing, pain vigilance, negative affect, anxiety, pain intensity, and disability[39]. Similar results were reported in a systematic review of musculoskeletal pain, which linked increased pain-related fear and anxiety with higher pain intensity and disability levels[40]. Alamam et al[41] further demonstrated that, across cultures and regions, beliefs regarding pain, such as self-efficacy, pain catastrophizing, and pain-related fear, were associated with disability due to low back pain. Other studies have examined the relationship between pain and disability[42]. These psychological factors not only affect the intensity of pain but also potentially influence the patient recovery process and quality of life. Therefore, performing psychological assessments and interventions in patients before and after surgery may help improve postoperative pain management and functional recovery. As such, clinicians should assess patient levels of pain exaggeration to identify high-risk patients and optimize pain management through early intervention. While previous studies have explored the association between post-traumatic chronic pain, functional impairment, and psychological symptoms, such as depression and anxiety, our study demonstrated the robustness of the association between psychological factors and post-traumatic outcomes across multiple acute orthopedic trauma types. We simultaneously examined bidirectional associations using validated indexes for chronic pain, such as the VAS, functional impairment (i.e., DRI), depression (i.e., HAMD), and anxiety (i.e., HAMA), thus supporting the need for routine mental health screening in trauma rehabilitation. This differs from previous studies that focused on one-dimensional relationships.

Results of the present study indicated a significant correlation between psychological factors (depression and anxiety) and levels of chronic pain and disability in patients after surgery for acute orthopedic trauma. This finding aligns with the existing literature, with numerous studies highlighting the association between mental health indices and pain-disability outcomes. After acute orthopedic trauma, patients often experience concurrent physical and psychological challenges, where higher depression and anxiety scores are associated with higher pain perception and more severe disability.

Psychological distress is a recognized risk factor for chronic pain, with persistent distress and lifetime stressors associated with pain progression[43]. Additionally, pain-related injustice, characterized by negative perceptions of pain-related losses, has been linked to a poor prognosis and heightened pain hypervigilance[44]. The magnitude of psychological distress is correlated with the severity and duration of disability, emphasizing the need for an integrated assessment[45]. Given the complexity of chronic pain, the role of psychological factors in pain management should not be ignored. Our study revealed a significant positive correlation between the VAS pain scores and HAMD and HAMA scores, indicating that higher levels of depression and anxiety are associated with greater reported pain intensity. This is largely consistent with previous research, suggesting that depression and anxiety not only affect the subjective experience of pain but may also influence the biological basis of pain through physiological mechanisms, such as altering nerve conduction and inflammatory responses[46-48].

Second, the DRI was significantly correlated with psychological state, further supporting the importance of mental health in functional recovery. Studies have shown that improvements in mental health can significantly improve functional recovery levels and that pain-related disabilities are correlated with psychological distress and pain intensity. This relationship may be reciprocal, which is consistent with previous research indicating that individuals with higher distress levels report increased pain intensity and disability[49,50]. This suggests that in clinical practice, in addition to focusing on patients' physical rehabilitation, we should also emphasize the assessment and intervention of mental health to promote comprehensive recovery.

Comprehensive consideration of a patient’s mental health status is crucial for developing personalized treatment plans. Through psychological intervention, patients can effectively relieve pain perception and improve their functional recovery and quality of life. In addition, establishing a multidisciplinary team that includes mental health professionals can provide patients with more comprehensive support and ensure optimal treatment results, both physically and psychologically. This integrated approach not only helps improve patient satisfaction but may also reduce medical costs, reduce the occurrence of long-term disability, and ultimately promote comprehensive recovery.

Limitations

The present study had some limitations, the first of which was its retrospective design and the possibility of inherent selection bias. Because this was a single-center study, there may be differences in specific confounding factors, such as patient complications and surgical or postoperative care options, which may limit the generalizability of the findings to a wider population. Future prospective multicenter studies should aim to increase the generalizability of the results.

Second, while our Pearson correlation analysis identified a significant association between psychological factors (depression/anxiety) and pain/disability outcomes, we did not perform multivariate regression to control for potential covariates, such as age, type of injury, BMI, injury severity, analgesic use, or surgical approach. These variables confound the observed relationships. Future research should incorporate multivariate models to account for these covariates and to enhance causal reasoning. Third, our assessment of chronic pain did not systematically record long-term postoperative outcomes (e.g., 3 months vs 12 months) in all patients. Therefore, the results of this study cannot explain the long-term relationship between chronic pain and various psychological factors. Future studies should implement standardized follow-up intervals to better characterize the prognosis of postoperative pain. In addition, the nature of our retrospective studies was not possible to determine how psychological factors affect pain over time. Future studies should include long-term follow-ups and longitudinal multicenter prospective designs to determine the long-term associations between psychological status and pain. In addition, the study did not consider other potential confounding factors, such as patients' social support, quality of life, and other health conditions, which may affect the perception of pain and disability. The study relied on self-reported measures (i.e., VAS, DRI, HAMD, HAMA) and, although these scales are widely used in clinical studies, their validity may be compromised in individuals with comorbid depression or anxiety. Therefore, future research should comprehensively consider these factors and further explore the effectiveness of interventions (such as psychotherapy and cognitive-behavioral therapy) in improving the mental health of individuals who experience acute orthopedic trauma and their impact on pain and disability to provide more specific guidance for clinical practice.

CONCLUSION

In summary, results of the present study indicate a significant correlation between chronic pain and disability after surgery for acute orthopedic trauma and psychological factors (depression and anxiety). We suggest routine psychological screening (e.g., HAMD/HAMA assessment within 1 month postoperatively) in high-risk patients (VAS score ≥ 70) in clinical practice, inclusion of mental health professionals in multidisciplinary trauma teams to reduce the incidence of chronic pain by 35%, and patient education. Future research directions should include longitudinal multicenter studies to track biomarkers (e.g., cortisol and interleukin-6) and conduct intervention trials (e.g., mindfulness-based therapy) to validate causal pathways and optimize integrated care.