Date of Award

January 2015

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Jonathan N. Grauer

Subject Area(s)

Surgery, Medicine, Statistics


Specific Aims:

1. Identify patients undergoing hip fracture repair, ankle fracture open reduction and internal fixation (ORIF), and arthroscopic meniscectomy procedures from a prospectively-collected national surgical registry

2. Identify risk factors for 30-day readmission following orthopaedic procedures using bivariate and multivariate analysis

3. Compare risk factors between procedures to determine general risk factors for readmission versus procedure-specific risk factors.


The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2011-2012 was queried to identify patients who had undergone hip fracture surgery, ankle fracture open reduction and internal fixation (ORIF), and arthroscopic meniscectomy using International Classification of Diseases, Ninth Revision (ICD-9) diagnosis codes and Current Procedural Terminology (CPT) codes. Patient and operative variables were extracted from the database and tested for association with readmission within 30 days of the procedure using bivariate and multivariate logistic regression. The results of these analyses were compared between procedures to determine which risk factors were procedure-specific.


Out of the 8,434 hip fracture patients that met inclusion criteria, a total of 846 patients (10.0%) were readmitted within 30 days postoperatively. On multivariate analysis, age >= 90 (OR 1.49, p = 0.003), male sex (OR 1.36, p < 0.001), body mass index >= 35 (OR 1.67, p = 0.007), American Society of Anesthesiologists (ASA) classification >= 3 (OR 1.39, p = 0.011), history of pulmonary disease (OR 1.47, p < 0.001), history of hypertension (OR 1.30, p = 0.008), history of heart disease (OR 1.30, p = 0.043), steroid use (OR 1.47, p = 0.013), dependent functional status (OR 1.31, p = 0.001), and discharge to a facility (OR 1.38, p = 0.030) were associated with readmission.

Of the 2,521 patients with ankle fractures who met study inclusion criteria, eighty patients (3.2%) were readmitted within the first 30 postoperative days. Only ASA classification >= 3 (OR 2.46, p < 0.001) was associated with readmission on multivariate analysis.

A total of 10,477 meniscectomy patients were included in this study, and 102 (3.2%) were readmitted within 30 days of the procedure. Multivariate analysis found ASA classification >= 3 (OR 2.07, p = 0.001) and history of smoking (OR 1.64, p = 0.040) to be independently associated with readmission.

The average time from discharge to readmission was 9.0 ± 15.7 days for hip fracture repair, 12.2 ± 8.4 days for ankle fracture ORIF, and 8.9 ± 25.6 for arthroscopic meniscectomy.


Readmission is an important topic in the current healthcare climate, as readmission rates after hospital discharge have become a marker for healthcare quality. Identifying risk factors for readmission after orthopaedic procedures such as hip fracture surgery, ankle fracture ORIF, and arthroscopic meniscectomy provides valuable information to patients and providers in terms of procedure planning and evaluating care quality. Of the risk factors for readmission identified in this study, smoking cessation prior to arthroscopic meniscectomy is a potentially modifiable factor that is likely affect this metric. Obesity, control of hypertension, and control of diabetes are also potentially modifiable factors for readmission in the hip fracture population. Non-modifiable risk factors for readmission that have been identified can be used to properly risk-stratify patients, and future research should target these patients in order to optimize postoperative care.