Elizabeth L. Lord

Operative versus nonoperative treatment of acute Achilles tendon rupture: An analysis of 12,570 patients in a large healthcare database

BACKGROUND The purpose of this study was to compare the latest patient demographics and rerupture rates of operative versus nonoperative treatment of acute Achilles tendon rupture in the United States. METHODS Patients undergoing treatment of an acute Achilles tendon rupture from 2007 to 2011 were identified by cross-referencing ICD-9-CM and CPT codes through the PearlDiver Patient Record Database. RESULTS In total, 12,570 patients were treated for an acute Achilles tendon rupture. The ratio of operative to nonoperative treatment increased from 1.41 to 1.65. Males were more likely to undergo surgery than females. There were no significant differences in short-term rerupture rate for operative (2.1%) versus nonoperative (2.4%) treatment. CONCLUSIONS The proportion of patients who received operative treatment for an acute Achilles tendon rupture increased slightly during the 5 year period, suggesting that surgeons in the United States have been slower to adopt nonoperative treatment than their European counterparts.

Effect of disc degeneration on lumbar segmental mobility analyzed by kinetic magnetic resonance imaging.

Study Design. Retrospective radiographical study. Objective. To define the relationship between the grade of disc degeneration and the motion of the lumbar spine by using kinetic magnetic resonance imaging. Summary of Background Data. Disc degeneration is common after middle age. Lumbar instability has generally been recognized as a potential risk factor of low back pain. However, correlations between the grade of disc degeneration and the motion of the lumbar spine need more investigation. Methods. Kinetic magnetic resonance imaging was performed in 162 patients with symptomatic low back pain without prior history of surgery. The lumbar intervertebral discs were graded by spine surgeons according to the degenerative grading system (grades I–V). Translational motion and angular variation were measured at each segment from L1–L2 through L5–S1. The relationship between the degree of lumbar disc degeneration and extent of lumbar spine mobility was analyzed. Results. The translational motion in discs with grade I through IV increased gradually, but decreased with grade V. Compared with other less degenerative grades, grade V discs had significantly decreased total intervertebral translational motion (P < 0.05). The angular variation in discs with grade I through IV was fairly constant, but decreased with grade V. Compared with other degenerative grades (I–IV), grade V discs had significantly decreased total intervertebral translational motion (P < 0.05). For less degenerative grades I and II discs, the L2–L3 and L3–L4 segmental units contributed the majority of total angular mobility of the spine. However, for the severely degenerated segments, grade V discs, the contributions of the L2–L3 and L3–L4 significantly decreased (P < 0.01). Conclusion. As disc degeneration developed from the normal to an increasingly severe stage, the motion of lumbar spine progressed from the normal stage to an unstable phase with higher mobility and finally to an ankylosed stage where stability was increased. Level of Evidence: 3

Demographic Trends and Complication Rates in Arthroscopic Elbow Surgery

PURPOSE To investigate demographic trends in elbow arthroscopy over time, as well as to query complication rates requiring reoperation associated with these procedures. METHODS The Current Procedural Terminology (CPT) billing codes of patients undergoing elbow arthroscopy were searched using a national insurance database. From the years 2007 to 2011, over 20 million orthopaedic patient records were present in the database with an orthopaedic International Classification of Diseases, Ninth Revision diagnosis code or CPT code. Our search for procedures and the corresponding CPT codes for the elbow included diagnostic arthroscopy, loose body removal, synovectomy, and debridement. The type of procedure, date, gender, and region of the country were identified for each patient. In addition, the incidence of reoperation for infection, stiffness, and nerve injury was examined. RESULTS There was a significant increase in arthroscopic elbow procedures over the study period. Male patients accounted for 71% of patients undergoing these procedures. Of the elbow arthroscopy patients, 22% were aged younger than 20 years, 25% were aged 20 to 39 years, 47% were aged 40 to 59 years, and 6% were aged 60 years or older. Other than synovectomy, there were regional variations in the incidence of each procedure type. The overall rate of reoperation was 2.2%, with specific rates of 0.26% for infection, 0.63% for stiffness, and 1.26% for nerve injury. It should be noted that because only the complications requiring reoperation are recorded in the database, these numbers are lower than the overall complication rate. CONCLUSIONS Overall, the incidence of elbow arthroscopy in this patient population is relatively low and appears to be increasing slightly over time. In the database used in this study, elbow arthroscopy procedures were most commonly performed in male patients and in patients aged 40 to 59 years, with regional variation in the incidence of the different procedures. Furthermore, the rate of complications requiring reoperation was low, with a nerve operation being the most common reoperation performed. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Risk factors for missed dynamic canal stenosis in the cervical spine.

Study Design. Retrospective analysis of kinematic magnetic resonance (MR) images. Objective. To elucidate the distribution and risk factors associated with missed dynamic stenosis in cervical spine. Summary of Background Data. Motion of the cervical spine is widely accepted to be associated with cervical spondylotic myelopathy; however, the distribution and the risk factors for dynamic spinal stenosis are not well understood. Methods. A total of 435 symptomatic patients (2610 cervical segments) obtained upright kinematic MR images in neutral, flexion, and extension postures. Spinal cord compression (SCC), spondylolisthesis, disc bulging, angular motion, translational motion, disc degeneration grade, Modic changes, segmental alignment, and developmental stenosis were all evaluated. Cervical segments C2–C3 to C7–T1 were divided into 2 groups, determined by the presence of SCC. After excluding segments with SCC in the neutral position, a multivariate logistic regression model was used to evaluate for associated risk factors of SCC in flexion and extension that were not present in the neutral position. Results. SCC in neutral position was observed in 5.3% (139/2610) of segments. After excluding these segments, missed dynamic stenosis was found in 8.3% (204/2471) of segments in extension and 1.6% (40/2471) in flexion. Missed dynamic stenosis in both extension and flexion was most frequent at C5–C6. Multivariate logistic regression analysis for dynamic stenosis in extension revealed that disc bulge greater than 2.4 mm, angular motion greater than 4.8°, moderate and severe disc degeneration, segmental kyphosis, and developmental stenosis were significant risk factors. In flexion, significant risk factors were a disc bulge of 1.9 mm or greater, moderate to severe disc degeneration, and segmental kyphosis. Conclusion. Dynamic cord compression was most common at the C5–C6 segment. Cervical segments with greater disc bulge, more severe disc degeneration, greater angular motion, segmental kyphosis, and developmental stenosis may be at risk for missed dynamic stenosis. Level of Evidence: 2

Trends associated with distal biceps tendon repair in the United States, 2007 to 2011

BACKGROUND Current studies investigating surgical treatment of distal biceps tendon tears largely consist of small, retrospective case series. The purpose of this study was to investigate the current patient demographics, surgical trends, and postoperative complication rates associated with operative treatment of distal biceps tendon tears using a large database of privately insured, non-Medicare patients. METHODS Patients who underwent surgical intervention for distal biceps tendon tears from 2007 to 2011 were identified using the PearlDiver database. Demographic and surgical data as well as postoperative complications were reviewed. Statistical analysis was performed using linear regression analysis and χ(2) tests, with statistical significance set at P < .05. RESULTS A total of 1443 patients underwent surgical treatment for distal biceps tendon tears. Men and patients aged 40 to 59 years accounted for 98% and 72% of the cohort, respectively. Regarding surgical technique, reinsertion to the radial tuberosity was preferred (95%) over tenodesis to the brachialis (5%) (P < .01). In total, revision surgery for tendon rerupture occurred in 5.4% of treated patients. The incidence of revision surgery for rerupture in acute and chronic distal biceps tears was 5.1% and 7.0%, respectively (P = .36). Postoperative infection and peripheral nerve injury rates were 1.1% and 0.6%, respectively. CONCLUSION Surgeons strongly preferred anatomic reinsertion to the radial tuberosity for treatment, regardless of the chronicity of the injury. Postoperative complication rates were similar to those found in prior studies, although the true rate of rerupture may be higher than previously thought.

Kinetic Magnetic Resonance Imaging of the Cervical Spine: A Review of the Literature

Study Design Literature review. Objective The purpose of this study is to compile and review the body of literature related to kinetic magnetic resonance imaging (kMRI) of the cervical spine. Methods A review of literature related to kMRI was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Results We included 16 prospective and retrospective studies of symptomatic and asymptomatic patients who underwent kMRI of the cervical spine. Conclusions Data suggest that kMRI is able to provide meaningful information regarding changes in the cervical spine in both normal and pathologic segments. A prospective study comparing magnetic resonance imaging and kMRI is needed to confirm clinically utility of this technology.

Paraspinal Muscle Atrophy After Lumbar Spine Surgery

Paraspinal muscles are commonly affected during spine surgery. The purpose of this study was to assess the potential factors that contribute to paraspinal muscle atrophy (PMA) after lumbar spine surgery. A comprehensive review of the available English literature, including relevant abstracts and references of articles selected for review, was conducted to identify studies that reported PMA after spinal surgery. The amount of postoperative PMA was evaluated in (1) lumbar fusion vs nonfusion procedures; (2) posterior lumbar fusion vs anterior lumbar fusion; and (3) minimally invasive (MIS) posterior lumbar decompression and/or fusion vs non-MIS equivalent procedures. In total, 12 studies that included 529 patients (262 men and 267 women) were reviewed. Of these, 365 patients had lumbar fusions and 164 had lumbar decompressions. There was a significantly higher mean postoperative volumetric PMA with fusion vs nonfusion procedures (P=.0001), with posterior fusion vs anterior fusion (P=.0001), and with conventional fusions vs MIS fusions (P=.001). There was no significant difference in mean volumetric lumbar PMA with MIS decompression vs non-MIS decompression (P=.56). There was significantly higher postoperative PMA with lumbar spine fusions, posterior procedures, and non-MIS fusions.

Surgical Treatment of Posterior Cruciate Ligament Insufficiency in the United States

The purpose of this study was to investigate the latest trends and demographics of surgical treatment of posterior cruciate ligament (PCL) insufficiency in the United States. Patients who underwent surgical treatment of PCL insufficiency from 2007 to 2011 were identified by searching the International Classification of Diseases, Ninth Revision, Clinical Modification codes and Current Procedural Terminology codes in the PearlDiver Patient Records Database (PearlDiver Technologies, Warsaw, Indiana), a publicly available national database of insurance records. The chronicity of injury, year of procedure, age, sex, region of the United States the surgery was performed, and other concomitant meniscus and ligamentous operations were elicited for each patient. In total, 701 cases of surgical PCL procedures (222 isolated and 479 combined) were identified. More PCL surgeries were completed for acute injuries (74%) than for chronic injuries (26%). Among associated procedures, meniscectomies and meniscus repairs were performed for 293 (41%) and 51 (7%) patients, respectively. Meniscectomies were completed in 77 (35%) isolated reconstructions vs 216 (45%) combined reconstructions (P=.01; odds ratio, 0.65). Of the combined PCL surgeries, anterior cruciate ligament (ACL)/PCL was the most common (62%), followed by ACL/PCL/collateral ligament repair (11%) and PCL/other ligamentous reconstruction (9%). No specific trends were observed in the yearly number of PCL procedures performed. The peak number of isolated PCL surgeries was observed in a younger age group (20-29 years) than that of combined PCL surgeries (30-39 years) (P<.01). Surgical treatment for PCL insufficiency remains reserved for acute multiligamentous knee injuries, with ACL/PCL operations being the most common combined procedure.

C5 Palsy After Cervical Spine Surgery: A Multicenter Retrospective Review of 59 Cases.

Study Design: A multicenter, retrospective review of C5 palsy after cervical spine surgery. Objective: Postoperative C5 palsy is a known complication of cervical decompressive spinal surgery. The goal of this study was to review the incidence, patient characteristics, and outcome of C5 palsy in patients undergoing cervical spine surgery. Methods: We conducted a multicenter, retrospective review of 13 946 patients across 21 centers who received cervical spine surgery (levels C2 to C7) between January 1, 2005, and December 31, 2011, inclusive. P values were calculated using 2-sample t test for continuous variables and χ2 tests or Fisher exact tests for categorical variables. Results: Of the 13 946 cases reviewed, 59 patients experienced a postoperative C5 palsy. The incidence rate across the 21 sites ranged from 0% to 2.5%. At most recent follow-up, 32 patients reported complete resolution of symptoms (54.2%), 15 had symptoms resolve with residual effects (25.4%), 10 patients did not recover (17.0%), and 2 were lost to follow-up (3.4%). Conclusion: C5 palsy occurred in all surgical approaches and across a variety of diagnoses. The majority of patients had full recovery or recovery with residual effects. This study represents the largest series of North American patients reviewed to date.

Current Animal Models of Postoperative Spine Infection and Potential Future Advances

Implant related infection following spine surgery is a devastating complication for patients and can potentially lead to significant neurological compromise, disability, morbidity, and even mortality. This paper provides an overview of the existing animal models of postoperative spine infection and highlights the strengths and weaknesses of each model. In addition, there is discussion regarding potential modifications to these animal models to better evaluate preventative and treatment strategies for this challenging complication. Current models are effective in simulating surgical procedures but fail to evaluate infection longitudinally using multiple techniques. Potential future modifications to these models include using advanced imaging technologies to evaluate infection, use of bioluminescent bacterial species, and testing of novel treatment strategies against multiple bacterial strains. There is potential to establish a postoperative spine infection model using smaller animals, such as mice, as these would be a more cost-effective screening tool for potential therapeutic interventions.