We conducted a retrospective analysis including 232 patients who underwent THA at our hospital from January 2013 to October 2015. The enrolled patients had to be able to be contacted via telephone after discharge and personally use WeChat or had to have family members that could send the WeChat content to the patient in a timely manner. Other inclusion criteria were as follows: patients with joint dysfunction because of various causes requiring THA, those aged > 65 years with normal cognitive function and normal abilities of communication, those who volunteered to participate in the study and signed informed consent, and those with junior high school-level education or higher. The exclusion criteria were as follows: patients with mental disorders and serious chronic diseases in the heart, lung and brain; those who could not take care of themselves or those who had been involved in a similar experiment before. The study protocol was approved by the ethics review committee of Honghui Hospital, Xi’an Jiaotong University College of Medicine (2012–0024), and all patients provided written informed consent to participate in the study and the use and publication of data for research purposes.
Grouping and interventions of the study
The enrolled patients were divided into two groups. In group A, the patients were provided with nursing intervention via telephone (which included THA-related knowledge, psychological support, dietary guidance, matters requiring attention after discharge, prevention of complications and rehabilitation guidance). In group B, the patients were provided with nursing intervention via WeChat. The interview content was sent via WeChat (the same content as that provided via telephone) to all patients.
While receiving routine rehabilitation guidance, the patients were provided with out-of-hospital rehabilitation guidance according to the contents of the procedures sent via telephone (group A) and WeChat (group B). Rehabilitation guidance mainly included the following contents: 1) 2–4 weeks after surgery: muscle strength training, range of motion training, wake-up activities, bed activities, sitting exercises, standing exercises, walking exercises and upstairs and downstairs exercises; 2) 5–12 weeks after surgery: muscle resistance training, range of motion training, weight-bearing and walking training and wearing shoes and socks. After discharge, the patients who underwent THA were followed-up once a week within the first month, once every 2 weeks from the second to third months and once a month from the fourth to sixth months (approximately 30 min for each follow-up).
Before participating in this study, all members of the study received unified training and were required to be qualified to perform the training through examination. The assessment included rehabilitation training and questionnaire filling guidance for patients who underwent THA at different stages following discharge.
Assessment of hip joint function
Postoperative hip joint function was evaluated using the Harris hip scale,  which includes scores for pain, function, range of motion and deformity. Function included seven items, which were as follows: wearing shoes and socks, need for walking aids, sitting on a chair, entering the car, limping, walking distance and climbing stairs. Each item was assigned a different score, and the final score was summarized and categorized into the following four grades: 90–100 points, excellent; 80–89 points, good; 70–79 points, moderate; and < 70 points, poor.
Assessment of quality of life
The Short-Form 36 (SF-36) questionnaire was used to assess the quality of life in patients . SF-36 is a self-administered generic questionnaire measuring physical and emotional function and general health (GH) perception. The scale measures the two dimensions of health on eight subscales, which reflect the impact of both dysfunctions and GH perceptions. Dysfunctions were measured using the following subscales: physical function, physical role, bodily pain, social function, and emotional role. Health perception was measured with three subscales: GH, vitality, and mental health. The responses correlated to each subscale were transformed into a score on a scale from 0 (lowest score) to 100 (highest score), with a higher score indicating a better health status or absence of limitations.
Assessment of functional Independence
The functional independence measure (FIM) scale was applied for comprehensively evaluating functional independence  and the therapeutic effect at each stage to determine the amount of nursing or time required by patients, to guide nursing work, and to evaluate the effect of the rehabilitation. The assessment criteria were as follows: 7 points, completely independent; 6 points, assisted independence; and 2 points, completely dependent. The FIM total score ranged from 18 (lowest score) to 126 points (highest score), and it was graded into three levels: totally independent (108–126 points), partially dependent (54–107 points) and totally dependent (18–54 points).
The Statistical Package for the Social Sciences software version 21.0 was used for the statistical analysis of all data. Measurement data were expressed as X¯[] ± S (means ± standard deviations), which were examined using t-test and repeated measures analysis of variance. In addition, categorical data were analyzed using the χ2 test. A P value of < 0.05 was considered statistically significant.