Cervical spine injuries in athletes: current return-to-play criteria

Rehabilitation of brachial plexus injury in contact sport: Where are the data that underpin clinical management? A scoping review

BACKGROUND

Although a common injury there is a lack of published primary data to inform clinical management of sports related brachial plexus injuries.

METHODS

A systematic search was completed in Medline, CINAHL, PubMed, SPORTDiscus and Web of Science databases and Google Scholar from inception to August 2023 according to the PRISMA-ScR guidelines. Methodological quality assessment of included articles was with the Joanna Briggs Institute tool. Studies providing primary data as to the rehabilitative management of diagnosed or suspected brachial plexus injuries sustained when playing contact sports were included.

RESULTS

Sixty-five studies were identified and screened, of which, 8 case reports were included, incorporating 10 participants with a mean age of 19.8 (±4.09) years. There was wide heterogeneity in injury severity, injury reporting, physical examination and imaging approaches documented. 9 of 10 participants returned to competitive sports, though follow-up periods also varied widely. Whilst return to play criteria varied between studies, the most consistent indicator was pain-free shoulder range of motion and strength.

CONCLUSIONS

There is a distinct lack of data available to inform evidence-based rehabilitation management of sports related brachial plexus injury. Only 8 individual case reports contain published data reporting on 10 athletes. Further reporting is critical to inform clinical management.

Return to Martial Arts after Surgical Treatment of the Cervical Spine: Case Report and Systematic Review of the Literature for an Evidence-Based Approach

Background: Cervical spine injuries are considered common in athlete populations, especially in those involved in high-contact sports. In some cases, surgical treatment can be necessary, and, therefore, return-to-play (RTP) after surgery represent a notable issue. Methods: We performed a systematic review of literature according to the PRISMA statement guidelines using the following search algorithm: (("ACDF") OR ("cervical spine surgery") OR ("neck surgery") OR ("cervical discectomy") OR ("foraminotomy") OR ("cervical disc replacement")) AND (("return to play") OR ("athlete") OR ("contact sports") OR ("martial arts")). The search was performed on 21 October 2022. We included only articles in which operative treatment for the cervical spine was performed and return to martial art activity was declared in the text. Results: Eight articles were selected, including 23 athletes who practice wrestling (n = 16), kickboxing (n = 1), sumo (n = 1) or other unspecified martial arts (n = 5). We also included the case of a young judoka who underwent anterior cervical discectomy and fusion (ACDF) at our hospital. About 88% (21 of 24 cases) of martial arts practitioners returned to play after cervical spine surgery, and no major complications were reported after RTP. Four patients (16.7%) returned in 0-3 months; 41.7% (10 of 24) returned in 3-6 months; 29.2% (7 of 24) returned after a period longer than 6 months. ACDF is the most used procedure. The level of evidence in the included articles is low: only case reports are available, including some single-case studies. Moreover, a small number of cases have been reported, and the examined data are very heterogeneous. Conclusions: Return to martial arts within one year after cervical spine surgery is generally safe, even if case-by-case evaluation is, however, necessary. Further studies are necessary to corroborate the present findings in a larger population.

Spinal Injuries in the Overhead Athlete

PURPOSE OF REVIEW

Treatment of overhead athletes requires a systematic approach that will make an accurate diagnosis, deliver effective treatment, and make timely and safe return to sport.

RECENT FINDINGS

New data has shown success rates and return to play effectiveness after different types of cervical and lumbar surgery. Cervical foraminotomy has been shown to have the highest rate and fastest return to play, but with the highest incidence of need for revision surgery. Cervical artificial disc replacement has shown promising results in the general population and is being done more commonly in elite athletes, but has an unknown risk for failure. Cervical fusion is a well-established and effective treatment, but has the longest healing time and risk for adjacent level pathology. In the lumbar spine, discectomy has a long and proven track record, fusion is rarely performed but can be effective, and artificial disc replacement is extremely rare in an elite athlete. An effective and comprehensive approach can diagnose, treat, and return overhead athletes to competitive play.

Cervical Disc Herniations, Radiculopathy, and Myelopathy

The key to successful treatment of elite athletes is optimizing the medical care at every step: injury prevention and sport-specific training; comprehensive history and physical examination; high-quality and complete diagnostic studies; accurate diagnosis; control and completion of rehabilitation program; minimally invasive, safe, and effective surgeries; risk assessment for return to sport; guided and gradual return to sport; and continued rehabilitation and exercise program after return to sport.

Static Versus Expandable Devices Provide Similar Clinical Outcomes Following Minimally Invasive Transforaminal Lumbar Interbody Fusion

BACKGROUND

Few studies have analyzed differences in radiographic parameters and patient-reported outcomes (PROs) between expandable and static interbody devices in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

QUESTIONS/PURPOSES

To evaluate differences in radiographic parameters and PROs following MIS TLIF between static and expandable interbody devices.

METHODS

Patients undergoing primary, single-level MIS TLIF between 2014 and 2017 were retrospectively identified. Radiographic measurements including lumbar lordosis (LL), segmental lordosis (SL), disc height (DH), and foraminal height (FH) were performed on lateral radiographs before and after MIS TLIF with a static or expandable articulating interbody device. Radiographic outcomes and PROs were compared using paired and unpaired Student's t test.

RESULTS

Thirty patients received expandable interbody devices and 30 patients received static interbody devices. The expandable device cohort exhibited significantly greater improvement in DH and FH at final follow-up compared with those receiving a static device. Both device cohorts experienced significant improvements in PROs at 6 months post-operatively.

CONCLUSION

MIS TLIF with an expandable interbody device led to a greater increase of DH and FH than with a static interbody device. Patients undergoing MIS TLIF can expect similar improvements in PROs whether receiving a static or an expandable interbody device. Further studies are required to better understand improvements in clinical outcomes afforded by expandable interbody devices.

Controversies in the Management of Cervical Spine Conditions in Elite Athletes

Cervical spine injuries in elite athletes can have detrimental consequences, which makes return to play for professional athletes after cervical spine injury controversial. Although most athletes can return to sport under some circumstances, such as single-level anterior cervical diskectomy and fusion for cervical disk herniation, return to play after cervical disk arthroplasty and multilevel fusion for cervical disk herniation remains controversial. Allowing athletes to return to play after a finding of cervical stenosis and in the incidence of pseudarthrosis remains unclear. This review provides a systematic framework to guide return-to-play decision-making in common cervical conditions in elite athletes. [Orthopedics. 2019; 42(4):e370-e375.].

Fusion Rates of Lateral Lumbar Interbody Fusion Using Recombinant Human Bone Morphogenetic Protein-2

STUDY DESIGN

Retrospective observational case series.

OBJECTIVES

Lateral lumbar interbody fusion (LLIF) has been widely performed with recombinant human bone morphogenetic protein-2 (rhBMP-2), but the fusion rates using this graft alternative have not been well studied. We aimed to evaluate fusion rates in 1- and 2-level LLIF with rhBMP-2 and their relationship with fixation, as well as rates of BMP-related complications.

METHODS

Institutional review board (IRB)-approved spine registry cohort of 93 patients who underwent LLIF with rhBMP-2 (71 one-level cases and 22 two-level cases). Minimum 1-year clinical follow-up and computed tomography (CT) scan for fusion assessment. Postoperative CT scans were used to evaluate the rate of fusion in all patients. Instrumentation and complications were collected from chart and imaging review.

RESULTS

Average age was 65 years (67% female). For 1-level cases, 92% (65/71) had complete fusion and 8% (6/71) had either incomplete or indeterminate fusion. Three of the 6 patients who had incomplete or indeterminate fusion had bilateral pedicle screw instrumentation, 1 patient had unilateral posterior fixation, and 2 had no fixation. In 2-level cases, 86% (19/22) had complete fusion and 14% (3/22) had either incomplete or indeterminate fusion. The 3 patients who had incomplete or indeterminate fusion did not have fixation.

CONCLUSION

Interbody fusion rates with rhBMP-2 via LLIF was 92% in 1-level cases and 86% in 2-level cases, indicating that rhBMP-2 may be used as a viable graft alternative to allograft options for LLIF. Higher rates of pseudarthrosis occurred when not using fixation.

Return to Play After Anterior Cervical Discectomy and Fusion in Professional Athletes

BACKGROUND

Data are limited on return to play after anterior cervical discectomy fusion (ACDF) in professional athletes.

PURPOSE

To determine the rate and time of return to play among professional athletes after ACDF.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This study involved the prospective and retrospective review of patient charts and diagnostic studies as well as an internet search to collect data on a consecutive series of professional athletes who underwent cervical fusion by 1 of the 2 senior authors between 1982 and 2016. Demographic data included sport, preoperative symptoms and radiologic findings, date of surgery, level of surgery, postoperative symptoms and radiologic findings, and confounding factors (eg, other orthopaedic injuries). An internet search engine was used to determine date of return to play and length of career after surgery.

RESULTS

A total of 27 ACDFs were performed on 26 professional athletes: 12 National Football League athletes, 5 National Hockey League athletes, 5 Major League Baseball athletes, 3 National Basketball Association athletes, and 1 Major League Soccer athlete. Twenty-six procedures (96.3%) showed clinical and radiographic evidence of fusion, and 20 of 25 eligible players returned to play (80%). At the conclusion of this study, 2 players were still in the rehabilitation phase and expected to return at the start of the next National Football League season. The mean time to return to play in a professional game was 9.5 months (range, 5.0-20.2 months). Of 15 players who returned to play but had retired by the time of this study, the mean career length after fusion was 3.2 years (range, 0.1-8.0 years). Clinical follow-up ranged from 1 to 96 months, with a mean of 22.1 months and mode of 11 months.

CONCLUSION

After single-level ACDF, 80% of professional athletes were able to return to sport at approximately 9 months. The study findings will help athletes, physicians, and teams better predict outcome after ACDF surgery.

Common peripheral nerve injuries in sport: diagnosis and management

Peripheral nerve injuries are unusual in sport but impact an athlete's safe return to play. Nerve injuries result from either acute trauma (most commonly in contact/collision sports) or from repetitive microtrauma and overuse. Diagnosis of overuse nerve injuries includes nerve localization and surrounding soft-tissue anatomy, and must account for possible causes of repetitive microtrauma, including biomechanics, equipment, training schedule, and recovery. Prognosis is related to the type of nerve injury. Management should not simply be rest and gradual return to sport but should address biomechanical and training predispositions to injury. Understanding the type of injury and the tissues involved will guide appropriate rehabilitation decisions. Recognizing acute care considerations and implementing appropriate strategies can help minimize secondary trauma to an area following acute injury.

Return-to-Play Recommendations After Cervical, Thoracic, and Lumbar Spine Injuries: A Comprehensive Review

CONTEXT

Currently, there is a national focus on establishing and disseminating standardized guidelines for return to play for athletes at all levels of competition. As more data become available, protocols and guidelines are being refined and implemented to assist physicians, coaches, trainers, players, and parents in making decisions about return to play. To date, no standardized criteria for returning to play exist for injuries to the spine.

EVIDENCE ACQUISITION

Electronic databases including PubMed and MEDLINE and professional orthopaedic, neurosurgical, and spine organizational websites were reviewed between 1980 and 2015.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

Although clinical guidelines have been published for return to play after spine injury, they are almost exclusively derived from expert opinion and clinical experience rather than from well-designed studies. Furthermore, recommendations differ and vary depending on anatomic location, type of sport, and surgery performed.

CONCLUSION

Despite a lack of consensus and specific recommendations, there is universal agreement that athletes should be pain free, completely neurologically intact, and have full strength and range of motion before returning to play after spinal injury.

Significance of T2 Hyperintensity on Magnetic Resonance Imaging After Cervical Cord Injury and Return to Play in Professional Athletes

BACKGROUND:

Cervical cord magnetic resonance imaging (MRI) T2 hyperintensity is used as evidence of cord trauma in the evaluation and management of athletes in contact sports. The long-term pathophysiologic and prognostic value of this finding is poorly understood, especially in return to play (RTP).

OBJECTIVE:

To examine the significance of T2 hyperintensity in the cervical spinal cord of professional athletes.

METHODS:

Retrospective review of MRI T2 hyperintensity findings between 2007 and 2014 in 5 professional athletes. Pertinent examination and demographics, including mechanism of injury, surgical intervention, radiographs, MRI studies, long-term outcomes, and RTP recommendations were collected.

RESULTS:

Four National Football League players and 1 professional wrestler had prior traumatic neurapraxia that at the time of initial consultation had resolved. MRIs showed congenitally small cervical canal (1) and multilevel spondylosis/stenosis/disc herniation (4) along with focal cord T2 hyperintensity (5). The signal abnormalities were at C3/C4 (3), C4 mid-vertebral body (1), and C5/C6 (1). Four athletes had single-level anterior cervical discectomy and fusion, and 1 was nonoperative. Serial MRI imaging at 3 months after surgery showed hyperintensity partially resolved (4) and unchanged (1), and at 9-months 3 of the 5 completely resolved. Based on the author's RTP criteria, 4 of 5 were released to return to their sport. Clearance for RTP preceded complete resolution of MRI T2 hyperintensity in 3 of 4 athletes. The 2 athletes that have returned to profession sport have not had any additional episodes of neurapraxia or any cervical spine-related complications.

CONCLUSION:

MRI T2 hyperintensity in contact sport athletes who are symptom-free with normal examination and no evidence of spinal instability may not be a contraindication to RTP. Additional observations are needed to confirm this observation.

Surgical treatment of double-level isthmic spondylolisthesis

Isthmic spondylolisthesis, which is demonstrated in 4%–6% of the general population, is one of the most common types of spondylolisthesis. However, double-level isthmic spondylolisthesis is extremely rare. Only a few reports have examined the outcomes of surgical treatment of double-level spondylolisthesis. The authors present an unusual case of double-level isthmic spondylolisthesis of the lumbar spine. The patient had low-back pain for 20 years and did not respond to conservative treatment. Radiographs revealed bilateral pars defects at L-4 and L-5. Grade 2 isthmic spondylolisthesis was present, both at L4–5 and at L5–S1. The patient underwent decompression, reduction, and posterior lumbar interbody fusion with autogenous bone chips from posterior decompression. At follow-up after 12 months, the patient was free of pain, slippage was corrected, and fusion was achieved. Posterior lumbar interbody fusion with posterior instrumentation and reduction may yield good functional short-term results for double-level spondylolisthesis.

Outcomes After Anterior Cervical Discectomy and Fusion in Professional Athletes

BACKGROUND:

Significant controversy exists regarding when an athlete may return to contact sports after anterior cervical discectomy and fusion (ACDF). Return-to-play (RTP) recommendations are complicated due to a mix of medical factors, social pressures, and limited outcome data.

OBJECTIVE:

The aim of this study was to characterize our diagnostic and surgical criteria, intervention, postoperative imaging results, and rehabilitation and report RTP decisions and outcomes for professional athletes with cervical spine injuries.

METHODS:

Fifteen professional athletes who had undergone a 1-level ACDF by a single neurosurgeon were identified after a retrospective chart and radiographic review from 2003 to 2012. Patient records and imaging studies were recorded.

RESULTS:

Seven of the 15 athletes presented with neurapraxia, 8 with cervical radiculopathy, and 2 with hyperintensity of the spinal cord. Cervical stenosis with effacement of the cerebrospinal fluid signal was noted in 14 subjects. The operative level included C3-4 (4 patients), C4-5 (1 patient), C5-6 (8 patients), and C6-7 (2 patients). All athletes were cleared for RTP after a neurological examination with normal findings, and radiographic criteria for early fusion were confirmed. Thirteen of the 15 players returned to their sport between 2 and 12 months postoperatively (mean, 6 months), with 8 still participating. The RTP duration of the 5 who retired after full participation ranged from 1 to 3 years. All athletes remain asymptomatic for radicular or myelopathic symptoms or signs.

CONCLUSION:

After a single-level ACDF, an athlete may return to contact sports if there are normal findings on a neurological examination, full range of neck movement, and solid arthrodesis. There may be an increased risk of the development of adjacent segment disease above or below the level of fusion. Cord hyperintensity may not necessarily preclude RTP.

The use of platelet gel in postero-lateral fusion: preliminary results in a series of 14 cases

Over the last few years, some hemocomponents have been used advantageously in clinical neurosurgical practice, not systemically via transfusion but topically as a sealant (fibrin glue). This has diverted the attention of many authors to the role of platelets in the healing process. The combination of hyper-concentrated platelets and fibrin glue (fibrinogen, XIII factor, fibronectin) with activated thrombin produces a platelet gel that can be easily applied to "difficult" wounds. This topical use of hemocomponents has gained an important role in regenerative medicine. The authors have considered the possibility of using a preparation with a high autologous platelet concentration applied in addition to autologous bone during vertebral postero-lateral fusion. The aim of the procedure is to induce a higher rate of vertebral fusion. Between November 2007 and November 2008, 14 patients (9 men and 5 women, mean age 58.9) underwent laminectomy, vertebral stabilization and postero-lateral fusion. The number of vertebral levels involved in stabilization was: 1 in 2 patients, 2 in 5 patients, 3 in 5 patients, 4 in 1 patient and 5 in 1 patient. Platelet gel was obtained by taking 16 ml of peripheral venous blood from the patient. For this procedure two patented test tubes were used for each patient, with a capacity of 8 m each. These make up the REGEN-THT(®) (Thrombocyte Harvesting Tube) system that makes it possible to obtain 8 ml of autologous platelet gel in 40-45 min. The addition of Ca gluconate and ethanol at 95% makes it possible to obtain a preparation of plasma rich in platelets and activated thrombin with a platelet concentration five times superior to the haematic one. The platelet gel is combined with fragments of autologous bone and synthetic bone during surgical operation. To allow a comparative assessment of the degree of fusion achieved with and without application of the platelet preparation in each patient, it was arbitrarily decided to use it in only one half of the operative field. All patients underwent serial CT scans 3 and 6 months after surgery as well as plain X-rays to evaluate bone fusion. The reconstructed CT images, especially in sagittal and axial planes, permitted an evaluation of the degree of vertebral fusion and "bone growth". The fusion rate was calculated measuring the increment of bone density on CT images, by means of an evaluation of the ROI (HU) in the newly formed bone, and comparing bone density within the bone callus formed by autologous and synthetic bone alone in the one to which the platelet preparation had been added. A good rate of fusion was observed in all patients. Furthermore, a comparative analysis of ROI at 3 and 6 months after surgery demonstrated a high increase in the fusion rate during the first 3 months after surgery. After 6 months the differences in ROI between the two sides had balanced out. However, at 6-month follow-up examination, bone density in the half of the surgical field in which platelet gel had been added to autologous-heterologous bone was higher in comparison to the contralateral one. Bony neoformation after posterior-lateral arthrodesis is well-evident 3 months after surgery and usually continues gradually for the following 18-24 months. The autologous platelet preparation used seems to accelerate bony deposition and to promote tissue healing, increasing bone density at the level of posterior-lateral arthrodesis. Moreover, this preparation has low production costs and is easy to apply.

Autologous growth factors versus autogenous graft for anterior cervical interbody fusion: an in vivo caprine model

OBJECT

Using an in vivo caprine model, authors in this study compared the efficacy of autologous growth factors (AGFs) with autogenous graft for anterior cervical interbody arthrodesis.

METHODS

Fourteen skeletally mature Nubian goats were used in this study and followed up for a period of 16 weeks postoperatively. Anterior cervical interbody arthrodesis was performed at the C3-4 and C5-6 vertebral levels. Four interbody treatment groups (7 animals in each group) were equally randomized among the 28 arthrodesis sites: Group 1, autograft alone; Group 2, autograft + cervical cage; Group 3, AGFs + cervical cage; and Group 4, autograft + anterior cervical plate. Groups 1 and 4 served as operative controls. Autologous growth factors were obtained preoperatively from venous blood and were ultra-concentrated. Following the 16-week survival period, interbody fusion success was evaluated based on radiographic, biomechanical, and histological analyses.

RESULTS

All goats survived surgery without incidence of vascular or infectious complications. Radiographic analysis by 3 independent observers indicated fusion rates ranging from 9 (43%) of 21 in the autograft-alone and autograft + cage groups to 12 (57%) of 21 in the autograft + anterior plate group. The sample size was not large enough to detect any statistical significance in these observed differences. Biomechanical testing revealed statistical differences (p < 0.05) between all treatments and the nonoperative controls under axial rotation and flexion and extension loading. Although the AGF + cage and autograft-alone treatments appeared to be statistically different from the intact spine during lateral bending, larger variances and smaller relative differences precluded a determination of statistical significance. Histomorphometric analysis of bone formation within the predefined fusion zone indicated quantities of bone within the interbody cage ranging from 21.3 +/- 14.7% for the AGF + cage group to 34.5 +/- 9.9% for the autograft-alone group.

CONCLUSIONS

The results indicated no differences in biomechanical findings among the treatment groups and comparable levels of trabecular bone formation within the fusion site between specimens treated with autogenous bone and those filled with the ultra-concentrated AGF extract. In addition, interbody cage treatments appeared to maintain disc space height better than autograft-alone treatments.

Return-to-play decisions after cervical spine injuries

This article summarizes the current evidence and expert opinion on making return-to-play decisions after cervical spine injuries. Injuries discussed include fractures, central cord neuropraxia, stringers, disc herniations, strains, sprains, and instability. Each of these injuries may be complicated by coexistence of other conditions making return-to-play decisions more complicated. The congenital, developmental, and disease processes discussed include spear tackler's spine, congenital and developmental stenosis, Klippel-Feil syndrome, odontoid abnormalities, rheumatoid arthritis, spina bifida, and Arnold-Chiari malformations. Postsurgical considerations are also discussed. This review represents an abundant amount of expert opinion that was overwhelmingly based on case series, case reports, and biomechanical studies to support the return-to-play guidelines.

Clinical outcomes and fusion success at 2 years of single-level instrumented posterolateral fusions with recombinant human bone morphogenetic protein-2/compression resistant matrix versus iliac crest bone graft

STUDY DESIGN

This is a prospective, randomized study comparing iliac crest bone graft to bone morphogenetic protein (BMP)/compression resistant matrix in instrumented posterolateral fusions for single-level lumbar degenerative disease. A higher recombinant human bone morphogenetic protein (rhBMP)-2 dose and a carrier specific for posterior spine applications were used.

OBJECTIVES

As part of a Food and Drug Administration IDE study, clinical outcomes and fusion rates of single-level instrumented posterolateral fusions using iliac crest bone graft or BMP/compression resistant matrix were evaluated.

SUMMARY OF BACKGROUND DATA

Although iliac crest graft is the gold standard for lumbar fusion, alternatives to obviate the morbidity of graft harvest have become available. Randomized clinical trials have demonstrated equivalent fusion rates and clinical outcomes with rhBMP-2 and a collagen sponge versus autograft in anterior lumbar fusions. A human pilot study using rhBMP-2 with biphasic calcium phosphate demonstrated similar results for posterolateral fusions.

METHODS

Demographic and perioperative data, Short Form 36, Oswestry Low Back Pain Disability Index, and leg and back pain scores were determined before surgery, and 1.5, 3, 6, 12, and 24 months after surgery. Independent neuroradiologists' evaluation of fine-cut computerized tomography scans with reconstructions were obtained at 6, 12, and 24 months.

RESULTS

There were 98 subjects, 45 in the iliac crest bone graft group and 53 in the BMP/compression resistant matrix group. There were no significant differences for age, weight, sex, smoking, or previous surgery between the groups. The average operative time (2.9 hours) and blood loss (465 cc) in the iliac crest bone graft group was greater than in the BMP/compression resistant matrix group (2.4 hours and 273 cc). There were no significant differences in any outcome measure at all time intervals. The fusion rate was lower in the iliac crest bone graft group (73%) than in the BMP/compression resistant matrix group (88%) at P = 0.051.

CONCLUSION

There was significant improvement of Short Form 36 (physical component score and pain), Oswestry Low Back Pain Disability Index, and leg and back pain scores in both groups over all time intervals. Surgical time and blood loss were significantly less in the BMP/compression resistant matrix group. The fusion rate in the BMP/compression resistant matrix group was significantly higher than the iliac crest bone graft group.

Estrogen-dependent actions of bone morphogenetic protein-7 on spine fusion in rats

STUDY DESIGN

Intertransverse process spinal fusion using recombinant human bone morphogenetic protein-7 (rhBMP-7) was performed in intact and ovariectomized female rats.

OBJECTIVES

To examine fusion rates in intact and ovariectomized female rats using rhBMP-7 to determine if spine fusion is dependent on estrogen status.

SUMMARY OF BACKGROUND DATA

Rat spinal fusion has been established as a consistent, efficient model for posterolateral intertransverse process fusion. Previous experiments have confirmed the efficacy of pellets containing the carrier, insoluble collagen bone matrix (ICBM), and rhBMP-7 to augment intertransverse process single level fusion in a rat model. Studying these implications in an osteoporosis model is of clinical value because there are many patients undergoing spinal fusion surgery that have osteoporotic bone disease, and there is a steady increase in this group of patients.

METHODS

A total of 15 ovariectomized and 15 intact Sprague-Dawley female rats were randomly assigned to groups receiving 25 mg ICBM alone, 25 mg ICBM + 10 microg rhBMP-7, and 25 mg ICBM + 30 microg rhBMP-7. Spinal fusion was evaluated by manual motion testing at each lumbar segment, radiographic evaluation using the Lenke grading system, and histology.

RESULTS

Ovariectomized and intact rats receiving 25 mg carrier ICBM alone did not show spinal fusion. With 25 mg ICBM + 10 microg rhBMP-7, there was not a significant difference in fusion rates between intact and ovariectomized rats (P = 0.63). Ovariectomized rats receiving 25 mg ICBM + 30 microg rhBMP-7 showed significantly lower fusion rates than intact rats (P = 0.013).

CONCLUSION

These data suggest that spinal fusion using rhBMP-7 is estrogen-dependent in rats. At the dosages used, rhBMP-7 was unable to overcome the inhibitory effects of estrogen deficiency on spinal fusion.

Management of Common Neurologic Conditions in Sports

Neurological conditions are common in athletes. Trauma can cause direct central (eg, concussion or hemorrhage) or peripheral (eg, stinger) injury. Also, as neurological conditions in athletes become better understood, more people who have pre-existing conditions are becoming involved in organized sports. This article reviews assessment and initial management of head injury, stingers, seizures, and headaches. Return-to-play criteria are also discussed.

Efficacy of autologous growth factors in lumbar intertransverse fusions

STUDY DESIGN AND OBJECTIVES

A retrospective, consecutive series with "blinded" radiographic review was performed to evaluate two groups undergoing lumbar fusion: one with and one without autologous growth factors (AGF).

SUMMARY OF BACKGROUND DATA

AGF has been shown to promote bone formation in vitro and in vivo in animal studies. Accordingly, it has been promoted to augment lumbar intertransverse fusions. To date, however, no controlled studies have been performed to assess its ability to do so in humans. This article presents the first such study.

MATERIALS AND METHODS

Two groups were studied. The control group consisted of 27 consecutive patients who underwent a single-level intertransverse lumbar fusion using iliac crest bone graft for either degenerative disk disease (DDD) or degenerative spondylolisthesis from January 1999 to November 1999. The AGF group consisted of 32 consecutive patients undergoing an identical procedure for the same indications with iliac crest bone graft augmented with AGF from January 2000 to November 2000. Fusions were assessed radiographically at 1 and 2 years by two independent spine surgeons on AP and lateral flexion/extension radiographs.

RESULTS

The fusion rate for the control group was 24 of 27, or 91%. The fusion rate for the AGF group was 18 of 32 or 62%.

CONCLUSIONS

In this study, the use of AGF resulted in inferior rates of arthrodesis compared with autogenous bone graft alone. Although it is important to note there are several techniques available to produce AGF and that the concentration of AGF may differ between individuals, based on the authors' findings, they cannot recommend the use of AGF for this indication until further clinical studies, perhaps altering these variables, prove otherwise.

Etiology, treatment, and prevention of athletic "stingers"

Stingers or burners are common in athletes, especially football players. They represent a traction, compression, or direct blow to the upper roots of the brachial plexus. They are usually transient and resolve quickly. Cervical canal stenosis with concurrent degenerative disc disease may predispose an athlete to this injury. Return-to-play criteria are largely based on the number of previous episodes and the duration of symptoms. These criteria also require appropriate consideration of any underlying pathological conditions. Appropriate counseling, including modification of tackling and addition of protective gear, in conjunction with complete rehabilitation, may be effective in preventing this condition or decreasing the rate of recurrence. The athlete, family, and coaches need to understand that recurrence remains unpredictable.

The effects of BMP-7 in a rat posterolateral intertransverse process fusion model

The use of autologous bone grafting is an essential component in spine fusion because it is the key factor in achieving long-term stable arthrodesis between spinal motion segments. However, harvesting autologous iliac crest bone graft can be associated with significant morbidity and its supply is limited. Although no current substitute for autologous graft is available, multiple studies have already established the success of bone morphogenetic proteins (BMPs) in augmenting spinal fusion in models using larger animals. The purpose of our study was to evaluate the ability of BMP to augment a posterolateral intertransverse process single-level fusion in a rat. To our knowledge, this model has not been used to evaluate the effects of recombinant BMPs. A posterolateral intertransverse process fusion was attempted in white male Sprague-Dawley rats. The following are the four study groups: insoluble collagen bone matrix (ICBM) alone, 3 microg BMP-7 + 25 mg ICBM, 10 microg BMP-7 + 25 mg ICBM, and a sham group with no implanted material. The animals were killed on postoperative day 21 and were evaluated for signs of clinical and/or radiographic fusion. All of the rats in the 10 microg BMP-7 + 25 mg ICBM group demonstrated clinical fusion and had solid bilateral fusion masses on radiographs. None of the rats in the sham group, ICBM group, or 3 microg BMP-7 + 25 mg ICBM group fused clinically; however, the rats in the 3 microg BMP-7 + 25 mg ICBM group did show evidence of new bone formation. Our study demonstrates that a rat posterolateral intertransverse process fusion model is inexpensive and efficient and produces consistent results. It also shows that BMP can augment fusion in a rat and that dosing plays a role in successful fusion. This is consistent with results that have been studied in larger animal models.

Recreational injuries in children: incidence and prevention

Participation in eight common types of recreational activities leads annually to more than 2 million medically treated musculoskeletal injuries in children aged 5 to 14 years. Many of these injuries could have been prevented if current safety guidelines and protective equipment had been used. Studies have demonstrated the value of safety education programs in preventing injuries. Parents consider their child's physician an important source of safety education, and orthopaedic surgeons have a unique opportunity to provide injury prevention counseling. The American Academy of Orthopaedic Surgeons recognizes the importance of injury prevention and has developed advocacy programs that are readily available to physicians and the public. Individual orthopaedists should be involved in injury prevention through patient education, research, community programs, and regulatory efforts that promote safe play for children.