Gregory D. Schroeder

The 100 most cited spine articles

PurposeSpine-related research has evolved dramatically during the last century. Significant contributions have been made by thousands of authors. A citation rank list has historically been used within a particular field to measure the importance of an article. The purpose of this article is to report on the 100 most cited articles in the field of spine.MethodsScience Citation Index Expanded was searched for citations in 27 different journals (as of 30 November 2010) chosen based on the relevance for all cited spine publications. The top 100 most cited articles were identified. Important information such as journal, date, country of origin, author, subspecialty, and level of evidence (for clinical research) were compiled.ResultsThe top 100 publications ranged from 1,695 to 240 citations. Fifty-three articles were of the lumbar, 17 were of the thoracolumbar, and 15 of the cervical spine. Eighty-one of the articles were clinical and 19 were basic science in nature. Level of evidence varied for the clinical papers, however, was most commonly level IV (34 of 81 articles). Notably, the 1990–1999 decade was the most productive period with 43 of the top 100 articles published during this time.ConclusionsIdentification of the most cited articles within the field of spine recognizes some of the most important contributions in the peer-reviewed literature. Current investigators may utilize the aspects of their work to guide and direct future spine-related research.

Performance-Based Outcomes After Nonoperative Treatment, Discectomy, and/or Fusion for a Lumbar Disc Herniation in National Hockey League Athletes

Background: Ice hockey players have a high incidence of lumbar spine disorders; however, there is no evidence in the literature to guide the treatment of an ice hockey player with a herniated lumbar disc. Purpose: To determine the performance-based outcomes in professional National Hockey League (NHL) athletes with a lumbar disc herniation after either nonsurgical or surgical treatment. Study Design: Descriptive epidemiological study. Methods: Athletes in the NHL with a lumbar disc herniation were identified through team injury reports and archives on public record. The return-to-play rate, games played per season, points per game, and performance score for each player were determined before and after the diagnosis of a lumbar disc herniation. Statistical analysis was used to compare preinjury and postinjury performance measures for players treated with either nonsurgical or surgical treatment. Results: A total of 87 NHL players met the inclusion criteria; 31 underwent nonoperative care, 48 underwent a discectomy, and 8 underwent a single-level fusion. The return-to-play rate for all players was 85%. There was a significant decrease in performance in all players after a lumbar disc herniation in games played per season, points scored per game, and performance score. A comparison of the posttreatment results for the nonsurgical and surgical patient groups revealed no significant difference in performance measures. Notably, the lumbar fusion group did not show a decrease in games played per season or performance score after surgery, likely secondary to a small sample size. Conclusion: National Hockey League players with a lumbar disc herniation have a high return-to-play rate regardless of the type of treatment; however, performance-based outcomes may decrease compared with preinjury levels. The study data suggest that a lumbar fusion is compatible with a return to play in the NHL, which is in contrast to other professional sports.

Rationale for the Surgical Treatment of Lumbar Degenerative Spondylolisthesis.

Study Design. A questionnaire survey. Objective. The aim of this study was to determine the effect of patient age, dynamic instability, and/or low back pain on the treatment of patients with a degenerative spondylolisthesis, and if the operative approach is affected by surgeon specialty, location, or practice model. Summary of Background Data. The classic treatment for patients with symptomatic degenerative spondylolisthesis is decompression and fusion; however in a select group of patients, an isolated decompression may be reasonable. Methods. A survey was sent to surgeon members of the Lumbar Spine Research Society and AOSpine requesting information regarding their preferred treatment of degenerative spondylolisthesis for a number of different clinical scenarios. Determinants included patient age, the presence of instability, symptoms of low back pain, surgeons location, surgeons specialty, and practice model. Results. A total of 223 spine surgeons completed the survey. Age of the patient, the presence of instability, and low back pain all significantly (P < 0.0001) affected the recommended treatment, which were independent of surgeon factors. Older patients were significantly less likely to be offered an interbody fusion and more likely to be recommended for an isolated decompression (P < 0.0001), and the presence of dynamic instability made an interbody fusion more likely than an isolated decompression (P < 0.0001). Of those who responded, 53.2% of surgeons reported they would recommend an isolated decompression for a properly selected patient with a degenerative spondylolisthesis. Conclusion. The most common operative treatment for a degenerative spondylolisthesis is a decompression and fusion; however, the results of this survey demonstrate that surgeons consider degenerative spondylolisthesis a heterogeneous condition that requires an individualized surgical plan. Future studies are needed to evaluate the effect of variables such as age, the presence of low back pain, and the presence of dynamic instability on patient reported outcomes from various surgical options. Level of Evidence: N/A.

Granulomatous Vertebral Osteomyelitis: An Update

A granulomatous infection of the spine is characterized by an infectious process within the spinal elements that results in the formation of a granuloma, an organized collection of transformed macrophages (ie, epithelioid cells), matrix, and other inflammatory cells. Causative organisms include various bacteria, fungi, or other parasites; however, the most frequently encountered causative organism is Mycobacterium tuberculosis (ie, Pott disease). The onset of these infections is often insidious, frequently leading to a delay in diagnosis. Left untreated, this disease process may lead to a compromise in the structural integrity of the spine and subsequent spinal deformity that may eventually result in compression of neural elements. Successful treatment of a granulomatous infection requires timely diagnosis, prompt medical management, and potential surgical intervention directed at the decompression of neural elements and the correction of spinal malalignment. Of granulomatous infections, tuberculous infections are the most thoroughly understood and serve as the standard to which other less commonly reported organisms are compared.

The Reliability and Validity of the Thoracolumbar Injury Classification System in Pediatric Spine Trauma.

Study Design. The thoracolumbar injury classification system (TLICS) was evaluated in 20 consecutive pediatric spine trauma cases. Objective. The purpose of this study was to determine the reliability and validity of the TLICS in pediatric spine trauma. Summary of Background Data. The TLICS was developed to improve the categorization and management of thoracolumbar trauma. TLICS has been shown to have good reliability and validity in the adult population. Methods. The clinical and radiographical findings of 20 pediatric thoracolumbar fractures were prospectively presented to 20 surgeons with disparate levels of training and experience with spinal trauma. These injuries were consecutively scored using the TLICS. Cohen unweighted &kgr; coefficients and Spearman rank order correlation values were calculated for the key parameters (injury morphology, status of posterior ligamentous complex, neurological status, TLICS total score, and proposed management) to assess the inter-rater reliabilities. Five surgeons scored the same cases 3 months later to assess the intra-rater reliability. The actual management of each case was then compared with the treatment recommended by the TLICS algorithm to assess validity. Results. The inter-rater &kgr; statistics of all subgroups (injury morphology, status of the posterior ligamentous complex, neurological status, TLICS total score, and proposed treatment) were within the range of moderate to substantial reproducibility (0.524–0.958). All subgroups had excellent intra-rater reliability (0.748–1.000). The various indices for validity were calculated (80.3% correct, 0.836 sensitivity, 0.785 specificity, 0.676 positive predictive value, 0.899 negative predictive value). Overall, TLICS demonstrated good validity. Conclusion. The TLICS has good reliability and validity when used in the pediatric population. The inter-rater reliability of predicting management and indices for validity are lower than those in adults with thoracolumbar fractures, which is likely due to differences in the way children are treated for certain types of injuries. TLICS can be used to reliably categorize thoracolumbar injuries in the pediatric population; however, modifications may be needed to better guide treatment in this specific patient population. Level of Evidence: 4

The impact of a cervical spine diagnosis on the careers of national football league athletes

Study Design. Cohort study. Objective. To determine the effect of cervical spine pathology on athletes entering the National Football League. Summary of Background Data. The association of symptomatic cervical spine pathology with American football athletes has been described; however, it is unknown how preexisting cervical spine pathology affects career performance of a National Football League player. Methods. The medical evaluations and imaging reports of American football athletes from 2003 to 2011 during the combine were evaluated. Athletes with a cervical spine diagnosis were matched to controls and career statistics were compiled. Results. Of a total of 2965 evaluated athletes, 143 players met the inclusion criteria. Athletes who attended the National Football League combine without a cervical spine diagnosis were more likely to be drafted than those with a diagnosis (P = 0.001). Players with a cervical spine diagnosis had a decreased total games played (P = 0.01). There was no difference in the number of games started (P = 0.08) or performance score (P = 0.38). In 10 athletes with a sagittal canal diameter of less than 10 mm, there was no difference in years, games played, games started, or performance score (P > 0.24). No neurological injury occurred during their careers. In 7 players who were drafted with a history of cervical spine surgery (4 anterior cervical discectomy and fusion, 2 foraminotomy, and 1 suboccipital craniectomy with a C1 laminectomy), there was no difference in career longevity or performance when compared with matched controls. Conclusion. This study suggests that athletes with preexisting cervical spine pathology were less likely to be drafted than controls. Players with preexisting cervical spine pathology demonstrated a shorter career than those without; however, statistically based performance and numbers of games started were not different. Players with cervical spinal stenosis and those with a history of previous surgery demonstrated no difference in performance-based outcomes and no reports of neurological injury during their careers. Level of Evidence: 3

Axial interbody arthrodesis of the L5-S1 segment: a systematic review of the literature.

OBJECT The object of this study was to determine the fusion rate and safety profile of an axial interbody arthrodesis of the L5-S1 motion segment. METHODS A systematic search of MEDLINE was conducted for literature published between January 1, 2000, and August 17, 2014. All peer-reviewed articles related to the fusion rate of L5-S1 and the safety profile of an axial interbody arthrodesis were evaluated. RESULTS Seventy-four articles were identified, but only 15 (13 case series and 2 retrospective cohort studies) met the study inclusion criteria. The overall pseudarthrosis rate at L5-S1 was 6.9%, and the rate of all other complications was 12.9%. A total of 14.4% of patients required additional surgery, and the infection rate was 5.4%. Deformity studies reported a significantly increased rate of complications (46.3%), and prospectively collected data demonstrated significantly higher complication (36.8%) and revision (22.6%) rates. Lastly, studies with a conflict of interest reported lower complication rates (12.4%). CONCLUSIONS A systematic review of the literature indicates that an axial interbody fusion performed at the lumbosacral junction is associated with a high fusion rate (93.15%) and an acceptable complication rate (12.90%). However, these results are based mainly on retrospective case series by authors with a conflict of interest. The limited prospective data available indicate that the actual fusion rate may be lower and the complication rate may be higher than currently reported.

Pre-existing Lumbar Spine Diagnosis as a Predictor of Outcomes in National Football League Athletes

Background: It is currently unknown how pre-existing lumbar spine conditions may affect the medical evaluation, draft status, and subsequent career performance of National Football League (NFL) players. Purpose: To determine if a pre-existing lumbar diagnosis affects a player’s draft status or his performance and longevity in the NFL. Study Design: Cohort study; Level 3. Methods: The investigators evaluated the written medical evaluations and imaging reports of prospective NFL players from a single franchise during the NFL Scouting Combine from 2003 to 2011. Players with a reported lumbar spine diagnosis and with appropriate imaging were included in this study. Athletes were then matched to control draftees without a lumbar spine diagnosis by age, position, year, and round drafted. Career statistics and performance scores were calculated. Results: Of a total of 2965 athletes evaluated, 414 were identified as having a pre-existing lumbar spine diagnosis. Players without a lumbar spine diagnosis were more likely to be drafted than were those with a diagnosis (80.2% vs 61.1%, respectively, P < .001). Drafted athletes with pre-existing lumbar spine injuries had a decrease in the number of years played compared with the matched control group (4.0 vs 4.3 years, respectively, P = .001), games played (46.5 vs 50.8, respectively, P = .0001), and games started (28.1 vs 30.6, respectively, P = .02) but not performance score (1.4 vs 1.8, respectively, P = .13). Compared with controls, players were less likely to be drafted if they had been diagnosed with spondylosis (62.37% vs 78.55%), a lumbar herniated disc (60.27% vs 78.43%), or spondylolysis with or without spondylolisthesis (64.44% vs 78.15%) (P < .001 for all), but there was no appreciable effect on career performance; however, the diagnosis of spondylolysis was associated with a decrease in career longevity (P < .05). Notably, 2 athletes who had undergone posterior lateral lumbar fusion were drafted. One played in 125 games, and the other is still active and has played in 108 games. Conclusion: The data in this study suggest that athletes with pre-existing lumbar spine conditions were less likely to be drafted and that the diagnosis is associated with a decrease in career longevity but not performance. Players with lumbar fusion have achieved successful careers in the NFL.

Preexisting Rotator Cuff Tears as a Predictor of Outcomes in National Football League Athletes

Background: A preexisting rotator cuff tear may affect the draft status and career performance of National Football League (NFL) players. Hypothesis: Preexisting rotator cuff tears decrease a player’s draft status, performance, and longevity in the NFL. Study Design: Retrospective cohort study. Level of Evidence: Level 3. Methods: Medical reports of prospective NFL players during the NFL Scouting Combine from 2003 to 2011 were evaluated to identify players with a previous rotator cuff tear. Athletes were matched to control draftees without documented shoulder pathology by age, position, year drafted, and round drafted. Career statistics and performance scores were calculated. Results: Between 2003 and 2011, 2965 consecutive athletes were evaluated. Forty-nine athletes had preexisting rotator cuff tears: 22 athletes underwent surgical intervention for their tear and 27 were treated nonoperatively. Those with a rotator cuff tear were significantly less likely to be drafted than those without a previous injury (55.1% vs 77.5%, P = 0.002). The 27 drafted athletes with preexisting rotator cuff tears started significantly fewer games (23.7 vs 43.0, P = 0.02) and played significantly fewer years (4.3 vs 5.7, P = 0.04) and significantly fewer games (47.1 vs 68.4, P = 0.04) than matched control athletes without rotator cuff tears. Conclusion: Athletes with a preexisting rotator cuff tear were less likely to be drafted and had decreased career longevity.

Lateral Mass Fixation in the Subaxial Cervical Spine.

The use of lateral mass screws and rods in the subaxial spine has become the standard method of fixation for posterior cervical spine fusions. Multiple techniques have been described for the placement of lateral mass screws, including the Magerl, the Anderson, and the An techniques. While these techniques are all slightly different, the overall goal is to obtain solid bony fixation while avoiding the neurovascular structures. The use of lateral mass screws has been shown to be a safe and effective technique for achieving a posterior cervical fusion.