The changing demographics of knee dislocation: a retrospective database review.

BACKGROUND: Knee dislocations are uncommon but devastating orthopaedic injuries. Little is known about their frequency and the types of patients who are affected. QUESTIONS/PURPOSES: Using a large national insurance database, we determined (1) the incidence of knee dislocation in patients with orthopaedic injuries and examined the incidence as a function of (2) year of diagnosis, (3) dislocation type (open versus closed, direction), and (4) patient demographic factors (sex, age). METHODS: We searched the PearlDiver database, a national database of private insurance records consisting of 11 million patients with orthopaedic diagnoses, using diagnosis (ICD-9-CM) codes for knee dislocation between the years 2004 and 2009. The PearlDiver database does not include Medicare, Medicaid, or uninsured patients. Patients were stratified by age, sex, and year of diagnosis. Incidence was defined as the number of dislocation events per 100 patient-years. RESULTS: We identified 8050 dislocations, representing an incidence of 0.072 events per 100 patient-years between 2004 and 2009. Annual dislocation incidence did not increase during the 6-year study period. Of the 8050 dislocations, 1333 (17%) were open and 6717 (83%) were closed, representing an incidence of 0.060 per 100 for closed dislocations and 0.012 per 100 for open dislocations. The most common direction of dislocation was unspecified or other (65%), followed by anterior (13%), lateral (11%), posterior (6%), and medial (5%). Of the patients sustaining dislocations, 4172 (52%) were female and 3878 (48%) were male. Males displayed an increased risk of knee dislocation compared to females (odds ratio = 1.09). The mean patient age was 35 years, and patient age was inversely correlated to the incidence of knee dislocation (10-year odds ratio = 0.77). CONCLUSIONS: Our data suggest that knee dislocation might represent a significantly larger burden among orthopaedic injuries than previously thought. The finding that males and females have a nearly equal risk of knee dislocation enhances the diagnosing physician's clinical suspicion of this injury. Future large prospective studies analyzing the various causes of knee dislocation could provide insight into the changing demographics of this injury. LEVEL OF EVIDENCE: Level IV, prognostic study. See Instructions for Authors for a complete description of levels of evidence.

Trends in the surgical treatment of articular cartilage defects of the knee in the United States.

PURPOSE: The purpose of this study was to evaluate trends in surgical treatment of articular cartilage defects of the knee in the United States. METHODS: The current procedural terminology (CPT) billing codes of patients undergoing articular cartilage procedures of the knee were searched using the PearlDiver Patient Record Database, a national database of insurance billing records. The CPT codes for chondroplasty, microfracture, osteochondral autograft, osteochondral allograft, and autologous chondrocyte implantation (ACI) were searched. RESULTS: A total of 163,448 articular cartilage procedures of the knee were identified over a 6-year period. Microfracture and chondroplasty accounted for over 98% of cases. There was no significant change in the incidence of cartilage procedures noted from 2004 (1.27 cases per 10,000 patients) to 2009 (1.53 cases per 10,000 patients) (p = 0.06). All procedures were performed more commonly in males (p < 0.001). This gender difference was smallest in patients undergoing chondroplasty (51 % males and 49% females) and greatest for open osteochondral allograft (61% males and 39% females). Chondroplasty and microfracture were most commonly performed in patients aged 40-59, while all other procedures were performed most frequently in patients <40 years old (p < 0.001). CONCLUSIONS: Articular cartilage lesions of the knee are most commonly treated with microfracture or chondroplasty in the United States. Chondroplasty and microfracture were most often performed in middle-aged patients, whereas osteochondral autograft, allograft, and ACI were performed in younger patients, and more frequently in males. LEVEL OF EVIDENCE: Cross-sectional study, Level IV.

Incidence of acute postoperative infections requiring reoperation after arthroscopic shoulder surgery.

BACKGROUND: An acute infection after arthroscopic shoulder surgery is a rare but serious complication. Previous studies estimating the incidence of infections after arthroscopic surgery have been conducted, but the majority of these had either relatively small study groups or were not specific to shoulder arthroscopic surgery. PURPOSE: To investigate the incidence of acute infections after arthroscopic shoulder surgery and compare infection rates by age group, sex, geographic region, and specific procedures. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective review of a large insurance company database was performed for all shoulder arthroscopic surgeries performed in the United States between 2004 and 2009 that required additional surgery for infections within 30 days. The data were stratified by sex, age group, and region. Data were also stratified for specific procedures (capsulorrhaphy, treatment for superior labrum anterior-posterior tears, claviculectomy, decompression, and rotator cuff repair) and used to assess the variation in the incidence of infections across different arthroscopic shoulder procedures. Linear regression was used to determine the significance of differences in the data from year to year. χ(2) analysis was used to assess the statistical significance of variations among all groups. Poisson regression analysis with exposure was used to determine significant differences in a pairwise comparison between 2 groups. RESULTS: The total number of arthroscopic shoulder surgeries performed was 165,820, and the number of infections requiring additional surgery was 450, resulting in an overall infection rate of 0.27%. The incidence of infections varied significantly across age groups (P < .001); the infection rate was highest in the ≥60-year age group (0.36%) and lowest in the 10- to 39-year age group (0.18%). The incidence of infections also varied by region (P < .001); the incidence was highest in the South (0.37%) and lowest in the Midwest (0.11%). The incidence of infection treatments was also significantly different between different arthroscopic procedures (P < .01) and was highest for rotator cuff repair (0.29%) and lowest for capsulorrhaphy (0.16%). The incidence did not significantly vary by year or sex. CONCLUSION: The overall infection rate for all arthroscopic shoulder procedures was 0.27%. The incidence was highest in elderly patients, in the South, and for rotator cuff repair. The incidence was lowest in young patients, in the Midwest, and for capsulorrhaphy. In general, shoulder arthroscopic surgery in this study population had a low rate of reoperation in the acute period.

The costs associated with the evaluation of rotator cuff tears before surgical repair.

BACKGROUND: Patients undergoing rotator cuff repair typically have a diagnostic evaluation and trial of nonoperative therapy before surgery. Recent studies have evaluated the cost-effectiveness of surgery, but none have attempted to estimate the costs associated with the preoperative evaluation. This study used available data to examine major expenditures during the preoperative period. MATERIALS AND METHODS: We conducted a search using an insurance company database to identify patients undergoing rotator cuff repair from 2004 to 2009. Patients were identified by the common Current Procedural Terminology codes for rotator cuff repair. The associated charge codes for the 90-day period before surgery were categorized as outpatient physician visits, diagnostic imaging studies, injections, physical therapy, laboratory and other preoperative studies, prior surgeries, and miscellaneous. The frequency of each code and the associated charges were noted. RESULTS: In total, 92,688 patients were identified in the study period. A total of $161,993,100 was charged during the preoperative period, for an average of $1,748 per patient. Diagnostic imaging charges totaled $104,510,646 (65%); injections, $5,145,227 (3%); outpatient visits, $29,723,751 (18%); physical therapy, $13,844,270 (8.5%); preoperative studies, $6,792,245 (4.2%); and miscellaneous, $1,164,688 (<1%). CONCLUSIONS: The costs for preoperative evaluation of rotator cuff tears are substantial, and the majority of the costs are associated with magnetic resonance imaging. To help reduce costs, future studies should attempt to identify the factors that predict which patients might not respond to nonoperative management and might benefit from early surgical intervention. In addition, magnetic resonance imaging should perhaps be reserved for patients in whom the diagnosis cannot be achieved by other modalities.

Incidence of postoperative infections requiring reoperation after arthroscopic knee surgery.

PURPOSE: The purposes of this study were to determine the incidence of infection requiring reoperation after arthroscopic knee surgery during a 6-year period and to compare infection rates across different age groups, genders, geographic regions of the United States, and Current Procedural Terminology (CPT) codes through a retrospective review of a large insurance company database. METHODS: A retrospective review of an insurance company database was performed for all knee arthroscopies performed in the United States from 2004 to 2009. The database was first queried for all knee arthroscopies, and the number of those cases requiring additional surgery for infection within 30 days was determined to calculate the incidence of infection. The incidence was stratified by gender, age group, region within the United States, and CPT code. A separate analysis for procedures using allografts was also performed. RESULTS: A total of 432,038 arthroscopic surgeries were performed, and the number of infections requiring drainage was 638, for an overall incidence of infection from 2004 to 2009 of 0.15%. Among adults, men were affected almost twice as often as women (P < .001), and among children, boys were affected almost 3 times as often as girls (P < .001). A decreasing incidence was noted in patients 60 years or older between 2004 and 2009 (P = .01). Overall, the incidence did not significantly vary by age, region, or CPT codes that specified the implantation of allograft tissue. Compared with diagnostic arthroscopy, the relative risk of infection was higher for CPT-29889 (posterior cruciate ligament reconstruction). CONCLUSIONS: The incidence of infection requiring reoperation after knee arthroscopy from 2004 to 2009 was 0.15%. The incidence was higher among male patients in both the adult and pediatric populations. The incidence of infection decreased from 2004 to 2009 in patients 60 years or older. Among adult patients, the incidence did not vary by age, by region, or by CPT codes that involved implantation of allografts. LEVEL OF EVIDENCE: Level IV, cross-sectional study.

Comparison of practice patterns in total ankle replacement and ankle fusion in the United States.

BACKGROUND: Although tibiotalar fusion has historically been considered the gold standard treatment for end-stage arthritis of the ankle, the performance of total ankle replacement appears to be gaining favor as improved outcomes have been observed with new implant designs and surgical techniques. The purpose of this study was to compare trends and demographics in the performance of ankle fusion and total ankle replacement in the United States. METHODS: The Current Procedural Terminology (CPT) codes of patients undergoing ankle fusion and total ankle replacement were searched using the PearlDiver Patient Record Database, a national database of orthopaedic patients. The CPT codes for open ankle arthrodesis (27870), arthroscopic ankle arthrodesis (29899), and total ankle replacement (27700, 27702) were searched for the years 2004 to 2009 to identify relative changes in the performance of ankle fusion and replacement over time. RESULTS: The performance of ankle fusion was unchanged during the 6-year study period. In contrast, an increase in total ankle replacement was observed, from 0.63 cases per 10 000 patients searched in 2004 to 0.99 cases per 10 000 patients in 2009 (P < .05). Both ankle fusion and total ankle replacement were performed most commonly in patients aged 60 to 69 years (P < .05). Although an even gender distribution was observed in patients undergoing total ankle replacement, open and arthroscopic fusion were more commonly performed in males (P < .05). With regard to regional distribution, open and arthroscopic fusion were most commonly performed in the western region of the United States, whereas total ankle replacement was performed most frequently in the Midwest (P < .001). CONCLUSIONS: In the population studied, the performance of total ankle replacement increased 57% from 2004 to 2009 and was performed equally in male and female patients when compared to ankle fusion, which was more often performed in males and was unchanged with time. LEVEL OF EVIDENCE: Level IV, cross-sectional study.