Predictors of Revision Surgery After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Arthroscopically assisted anterior cruciate ligament (ACL) reconstruction is a common orthopaedic procedure. Graft failure after reconstruction remains a devastating complication, often requiring revision surgery and less aggressive or modified rehabilitation. Worse functional and patient-reported outcomes are reported compared with primary reconstruction. Moreover, both rates and risk factors for revision are variable and inconsistent within the literature.

PURPOSE

To determine the rate of revision surgery after ACL reconstruction in a large cohort of patients, to assess the influence of patient characteristics on the odds of revision, and to compare revision rates between active-duty military members and non-active-duty beneficiaries.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Using administrative data from the Military Health System, a retrospective study was designed to characterize the rate of ACL revision surgery among patients treated within a military facility. All patients ≥18 years at the time of ACL reconstruction were identified using the American Medical Association Current Procedural Terminology (CPT) for ACL reconstruction (CPT code 29888) over 7 years (2005-2011). Revision ACL reconstructions were identified as having ≥2 ACL reconstruction procedure codes on the ipsilateral knee at least 90 days apart. Univariate analysis was performed to calculate odds ratios (ORs) for demographic, perioperative medication use, and concomitant procedure-related risk factors. A multivariate logistic regression model determined risk covariates in the active-duty cohort.

RESULTS

The study population consisted of 17,164 ACL reconstructions performed among 16,336 patients, of whom 83.3% were male with a mean ± SD age of 28.9 ± 7.6 years for the nonrevision group, and was predominantly active duty (89.2%). Patients undergoing ACL reconstruction on both knees only contributed their index knee for analyses. There were 587 patients who underwent revision surgery, corresponding to an overall revision rate of 3.6%. The median time from the index surgery to revision surgery was 500 days (interquartile range, 102-2406 days). Revision rates were higher in the active-duty cohort as compared with non-active-duty beneficiaries (3.8% vs 1.8%, respectively; OR, 2.14; 95% CI, 1.49-3.07). Based on multivariate logistic regression in the active-duty cohort, age ≥35 years (OR, 0.44; 95% CI, 0.33-0.58) and concomitant meniscal repair (OR, 0.69; 95% CI, 0.53-0.91) were found to be protective with regard to the odds of revision surgery. Perioperative medication use of nonsteroidal anti-inflammatory drugs (NSAIDs) (OR, 1.33; 95% CI, 1.12-1.58; number needed to harm [NNH], 100) and COX-2 inhibitors (OR, 1.31; 95% CI, 1.04-1.66; NNH, 333) was associated with increased odds of revision surgery. No significant findings were detected among sex, race, nicotine use, body mass index, or other concomitant procedures of interest.

CONCLUSION

In this large cohort study, the rate of revision ACL reconstruction was 3.6%, which is consistent with the existing literature. Increased odds of revision surgery among active-duty personnel were associated with the perioperative use of NSAIDs and COX-2 inhibitors. Age ≥35 years and concomitant meniscal repair were found to be protective against ACL revision.

The Prevalence of Symptomatic Deep Venous Thrombosis and Pulmonary Embolism After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Arthroscopically assisted anterior cruciate ligament (ACL) reconstruction is a common orthopaedic procedure. The incidence and risk factors of venous thromboembolism (VTE) after ACL reconstruction remain unclear.

PURPOSE

To define the incidence of VTE after ACL reconstruction and identify associated risk factors in a large cohort of patients.

STUDY DESIGN

Descriptive epidemiological study.

METHODS

All patients aged ≥18 years who underwent ACL reconstruction between 2005 and 2011 were identified from the Department of Defense Medical Data Repository. The prevalence of VTE, including deep venous thrombosis (DVT) and pulmonary embolism (PE), within 3 months of ACL reconstruction was queried. Univariate analyses were performed to define odds ratios (ORs) for demographic, medication use, and procedural-related risk factors.

RESULTS

A total of 87 VTE events (0.53% [95% CI, 0.42%-0.65%]) occurred after 16,558 ACL reconstructions performed on 15,767 patients. DVT was documented after 55 procedures and PE after 35 procedures. Three patients were documented to have both DVT and PE within the study period. The odds of VTE increased in patients aged ≥35 years (OR, 1.96 [95% CI, 1.27-3.04]; P = .003). Nicotine history increased the odds of DVT (OR, 1.99 [95% CI, 1.15-3.43]; P = .014). Concomitant high tibial osteotomy (HTO) increased the odds of PE (OR, 18.31 [95% CI, 2.4-139.6]; P = .005), whereas concomitant posterior cruciate ligament (PCL) reconstruction increased the odds of both VTE (OR, 3.43 [95% CI, 1.07-11.2]; P = .38) and DVT (OR, 5.57 [95% CI, 1.71-18.14]; P = .004). Nonsteroidal drug use was associated with decreased odds for VTE and DVT (OR, 0.44 [95% CI, 0.28-0.70]; P < .001 and OR, 0.38 [95% CI, 0.22-0.69]; P < .001, respectively). Anticoagulants were associated with increased odds for VTE, DVT, and PE (OR, 98.32 [95% CI, 61.63-156.86]; P < .001; OR, 111.93 [95% CI, 63.95-195.92]; P < .001; and OR, 47.84 [95% CI, 22.55-101.52]; P < .001, respectively). No detectible difference in odds was found for sex, body mass index, or aspirin or cyclooxygenase-2 inhibitor use.

CONCLUSION

The incidence of VTE after ACL reconstruction in this large population was low. Increased odds of VTE was identified in patients aged ≥35 years with a history of nicotine use, anticoagulant use, concomitant HTO, or concomitant PCL reconstruction. Controlled studies are necessary to determine the efficacy of chemoprophylaxis and to develop evidence-based clinical practice guidelines to minimize VTE after ACL reconstruction.

Variability of acetabular coverage between supine and weightbearing pelvic radiographs

BACKGROUND

Radiographic measures of acetabular coverage are essential screening tools used to characterize bony structure contributing to femoroacetabular impingement (FAI). Small changes in pelvic tilt result in altered radiographic measures of acetabular coverage. Positional changes in pelvic tilt are known to occur between the supine and weightbearing positions. It is unclear whether alteration of pelvic tilt between these positions is clinically sufficient to influence measures of acetabular coverage.

PURPOSE/HYPOTHESIS

To determine whether, and to what degree, imaging position (supine vs weightbearing) is capable of altering several measures of acetabular orientation: pubic symphysis to sacrococcygeal distance (PSSC), angle of Sharp (SA), Tönnis angle (TA), percentage of acetabular crossover (CO), and lateral center-edge angle of Wiberg (LCEA). The hypothesis was that imaging position would significantly alter all measures of acetabular orientation.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

A total of 50 consecutive symptomatic hips referred to a single provider for FAI were evaluated with standardized supine and weightbearing anteroposterior pelvic radiographs. Two independent reviewers blinded to patient positioning reviewed each radiograph at 2 separate time points. Mean measurements in each position were compared by use of paired Student t tests, and a Bonferroni-adjusted significance level of P = .01 was used to represent significance.

RESULTS

Statistically significant differences between the supine and weightbearing radiographs were identified for PSSC and all measures of acetabular coverage (P < .003). The mean PSSC decreased between the supine and weightbearing positions by an average of 13.4 mm (P < .001), thereby resulting in decreased mean LCEA, TA, SA, and CO of 1.2°, 1.3°, 0.8°, and 6.3%, respectively (P < .002). The change in positional pelvic tilt was not uniformly predictable and accounted for large measurement changes in some individuals. PSSC also demonstrated considerable inter- and intrasubject variability but averaged 55.8 mm supine and 44.9 mm weightbearing for females and 37.0 mm supine and 20.6 mm weightbearing for males.

CONCLUSION

In this study of nonarthritic adult patients with hip pain, the data indicate that positional changes are capable of significantly altering pelvic tilt and radiographic measures of acetabular coverage. It appears that the weightbearing position typically, but not universally, correlates with additional posterior pelvic tilt and decreased measures of acetabular coverage. Individual positional variability can contribute to large-magnitude changes in radiographic acetabular measures.

The effect of pelvic tilt on radiographic markers of acetabular coverage

BACKGROUND

Radiographic indices of acetabular coverage are crucial to objectively characterize femoroacetabular impingement and plan bony decompression. It is established that changes in pelvic inclination result in alterations of acetabular crossover; however, it is unclear what influence this has on other measures of acetabular anatomy.

HYPOTHESIS

The objective of the present study was to determine if, and to what degree, a variation in pelvic tilt alters 4 measures of acetabular anatomy: the angle of Sharp, Tönnis angle, percentage of acetabular crossover, and lateral center edge angle (LCEA). The hypothesis was that pelvic tilt would significantly alter all measures of acetabular coverage.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Fluoroscopic images of 8 adult hemipelvises were obtained at 7 positions of rotation in the sagittal plane to investigate the change of each measurement in response to pelvic orientation. Two reviewers obtained measurements from each image at 2 separate time points.

RESULTS

Each increment of pelvic inclination resulted in increased measures of acetabular coverage for all measurements, whereas each increment of decreased pelvic inclination resulted in decreased measures of acetabular coverage for all measurements. Significant differences in the measured LCEA, acetabular crossover, and Tönnis angle were identified at each increment of tilt as compared with neutral radiographs. No significant differences could be identified for the angle of Sharp.

CONCLUSION

Pelvic tilt significantly alters the measures of LCEA, crossover, and Tönnis angle in this cadaveric study. Pelvic inclination results in increased measures of acetabular coverage, whereas decreasing inclination decreases each measure.

CLINICAL RELEVANCE

Given the known individual and positional pelvic tilt variability, standing anteroposterior pelvic radiographs may provide a more physiological representation of acetabular coverage in the young adult population.

Surgical anatomy of the shoulder

The glenohumeral articulation is a versatile joint that requires a complex integration of bony ligamentous, musculotendinous, and neurovascular structures for proper function. Injuries resulting from dysfunction are common and potentially debilitating. Many of these injuries can be managed nonsurgically; however, if surgical treatment is indicated, a thorough knowledge of the anatomy of the shoulder girdle is critical. It is important for the surgeon to be aware of commonly used arthroscopic and surgical approaches to the glenohumeral joint along with anatomic structures at risk with each surgical approach and methods of avoiding injury.

Comparison of surgical outcomes of intra-articular calcaneal fractures by age

BACKGROUND

Internal fixation is an accepted treatment for displaced fractures of the calcaneus. Operative intervention in older patients, however, is traditionally discouraged in the literature. The purpose of this study was to compare the outcomes of internal fixation of intra-articular fractures of the calcaneus on the basis of patient age.

METHODS

One hundred and seventy-five patients (191 fractures) who underwent internal fixation between 1992 and 2007 for a displaced, intra-articular calcaneal fracture were identified. The American Society of Anesthesiologists score, the fracture pattern, and the mechanism of injury were recorded. Each patient was contacted to complete a follow-up survey from which clinical outcome scores were calculated. One hundred and forty-six patients with 158 fractures were available for follow-up and were divided into two groups for comparison. Group I consisted of 108 fractures in patients who were less than fifty years old. Group II was composed of fractures in fifty patients who were fifty years of age or older.

RESULTS

The mean duration of follow-up was 8.98 years. The average patient age was thirty-six years for Group I and fifty-eight years for Group II. The average adjusted American Orthopaedic Foot & Ankle Society score was 64 for Group I and 75 for Group II. The mean calcaneal fracture scoring system score was 66 for Group I, and 76 for Group II. Similarly, the average Foot Function Index was 24 and 15 for Groups I and II, respectively. Each clinical outcome measure suggests significantly better outcomes for Group II as compared with Group I (all p < 0.05). Overall, the complication rates were similar between groups. Conversion to subtalar fusion was 15% for Group I and 8% for Group II.

CONCLUSIONS

In this series, outcomes of older patients are at least equivalent to those of younger patients undergoing internal fixation for an intra-articular calcaneal fracture. Operative intervention appears to be a reasonable option for displaced calcaneal fractures in older patients. Physiologic age should be considered when evaluating older patients, and individualized treatment plans remain critical because patients with low physical demands or who have medical complications may be better candidates for nonoperative treatment. Prospective studies are needed in this area.

The financial impact of orthopaedic fellowship training

BACKGROUND

Previous reports have compared the expected financial return of a medical education with those expected in other professions. However, we know of no published report estimating the financial return of orthopaedic training. The purpose of this study was to estimate the financial incentives that may influence the decision to invest an additional year of training in each of the major orthopaedic fellowships.

METHODS

With survey data from the American Academy of Orthopaedic Surgeons and using standard financial techniques, we calculated the estimated return on investment of an additional year of orthopaedic training over a working lifetime. The net present value, internal rate of return, and the break-even point were estimated. Eight fellowships were examined and compared with general orthopaedic practice.

RESULTS

Investment in an orthopaedic fellowship yields variable returns. Adult spine, shoulder and elbow, sports medicine, hand, and adult arthroplasty may yield positive returns. Trauma yields a neutral return, while pediatrics and foot and ankle have negative net present values. On the basis of mean reported incomes, the break-even point was two years for spine, seven years for hand, eight years for shoulder and elbow, twelve years for adult arthroplasty, thirteen years for sports medicine, and twenty-seven years for trauma. Fellowship-trained pediatric and foot and ankle surgeons did not break even following the initial investment. When working hours were controlled for, the returns for adult arthroplasty and trauma became negative.

CONCLUSIONS

The financial return of an orthopaedic fellowship varies on the basis of the specialty chosen. While reasons to pursue fellowship training vary widely, and many are not financial, there are positive and negative financial incentives. Therefore, the decision to pursue fellowship training is best if it is not made on the basis of financial incentives. This information may assist policy makers in analyzing medical education economics to ensure the training of orthopaedic surgeons in all specialties and subspecialties.