Anterior Cervical Infection: Presentation and Incidence of an Uncommon Postoperative Complication.

STUDY DESIGN: Retrospective multi-institutional case series. OBJECTIVE: The anterior cervical discectomy and fusion (ACDF) affords the surgeon the flexibility to treat a variety of cervical pathologies, with the majority being for degenerative and traumatic indications. Limited data in the literature describe the presentation and true incidence of postoperative surgical site infections. METHODS: A retrospective multicenter case series study was conducted involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network, selected for their excellence in spine care and clinical research infrastructure and experience. Medical records for 17 625 patients who received cervical spine surgery (levels from C2 to C7) between January 1, 2005, and December 31, 2011, inclusive, were reviewed to identify the occurrence of 21 predefined treatment complications. Patients who underwent an ACDF were identified in the database and reviewed for the occurrence of postoperative anterior cervical infections. RESULTS: A total of 8887 patients were identified from a retrospective database analysis of 21 centers providing data for postoperative anterior cervical infections (17/21, 81% response rate). A total of 6 postoperative infections after ACDF were identified for a mean rate of 0.07% (range 0% to 0.39%). The mean age of patients identified was 57.5 (SD = 11.6, 66.7% female). The mean body mass index was 22.02. Of the total infections, half were smokers (n = 3). Two patients presented with myelopathy, and 3 patients presented with radiculopathic-type complaints. The mean length of stay was 4.7 days. All patients were treated aggressively with surgery for management of this complication, with improvement in all patients. There were no mortalities. CONCLUSION: The incidence of postoperative infection in ACDF is exceedingly low. The management has historically been urgent irrigation and debridement of the surgical site. However, due to the rarity of this occurrence, guidance for management is limited to retrospective series.

Rare Complications of Cervical Spine Surgery: Horner's Syndrome.

STUDY DESIGN: A multicenter retrospective case series. OBJECTIVE: Horner's syndrome is a known complication of anterior cervical spinal surgery, but it is rarely encountered in clinical practice. To better understand the incidence, risks, and neurologic outcomes associated with Horner's syndrome, a multicenter study was performed to review a large collective experience with this rare complication. METHODS: We conducted a retrospective multicenter case series study involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network. Medical records for 17 625 patients who received subaxial cervical spine surgery from 2005 to 2011 were reviewed to identify occurrence of 21 predefined treatment complications. Descriptive statistics were provided for baseline patient characteristics. Paired t test was used to analyze changes in clinical outcomes at follow-up compared to preoperative status. RESULTS: In total, 8887 patients who underwent anterior cervical spine surgery at the participating institutions were screened. Postoperative Horner's syndrome was identified in 5 (0.06%) patients. All patients experienced the complication following anterior cervical discectomy and fusion. The sympathetic trunk appeared to be more vulnerable when operating on midcervical levels (C5, C6), and most patients experienced at least a partial recovery without further treatment. CONCLUSIONS: This collective experience suggests that Horner's syndrome is an exceedingly rare complication following anterior cervical spine surgery. Injury to the sympathetic trunk may be limited by maintaining a midline surgical trajectory when possible, and performing careful dissection and retraction of the longus colli muscle when lateral exposure is necessary, especially at caudal cervical levels.

Misplaced Cervical Screws Requiring Reoperation.

STUDY DESIGN: A multicenter, retrospective case series. OBJECTIVE: In the past several years, screw fixation of the cervical spine has become commonplace. For the most part, this is a safe, low-risk procedure. While rare, screw backout or misplaced screws can lead to morbidity and increased costs. We report our experiences with this uncommon complication. METHODS: A multicenter, retrospective case series was undertaken at 23 institutions in the United States. Patients were included who underwent cervical spine surgery from January 1, 2005, to December 31, 2011, and had misplacement of screws requiring reoperation. Institutional review board approval was obtained at all participating institutions, and detailed records were sent to a central data center. RESULTS: A total of 12 903 patients met the inclusion criteria and were analyzed. There were 11 instances of screw backout requiring reoperation, for an incidence of 0.085%. There were 7 posterior procedures. Importantly, there were no changes in the health-related quality-of-life metrics due to this complication. There were no new neurologic deficits; a patient most often presented with pain, and misplacement was diagnosed on plain X-ray or computed tomography scan. The most common location for screw backout was C6 (36%). CONCLUSIONS: This study represents the largest series to tabulate the incidence of misplacement of screws following cervical spine surgery, which led to revision procedures. The data suggest this is a rare event, despite the widespread use of cervical fixation. Patients suffering this complication can require revision, but do not usually suffer neurologic sequelae. These patients have increased cost of care. Meticulous technique and thorough knowledge of the relevant anatomy are the best means of preventing this complication.

Esophageal Perforation Following Anterior Cervical Spine Surgery: Case Report and Review of the Literature.

STUDY DESIGN: Multicenter retrospective case series and review of the literature. OBJECTIVE: To determine the rate of esophageal perforations following anterior cervical spine surgery. METHODS: As part of an AOSpine series on rare complications, a retrospective cohort study was conducted among 21 high-volume surgical centers to identify esophageal perforations following anterior cervical spine surgery. Staff at each center abstracted data from patients' charts and created case report forms for each event identified. Case report forms were then sent to the AOSpine North America Clinical Research Network Methodological Core for data processing and analysis. RESULTS: The records of 9591 patients who underwent anterior cervical spine surgery were reviewed. Two (0.02%) were found to have esophageal perforations following anterior cervical spine surgery. Both cases were detected and treated in the acute postoperative period. One patient was successfully treated with primary repair and debridement. One patient underwent multiple debridement attempts and expired. CONCLUSIONS: Esophageal perforation following anterior cervical spine surgery is a relatively rare occurrence. Prompt recognition and treatment of these injuries is critical to minimizing morbidity and mortality.

Sagittal alignment as a predictor of clinical adjacent segment pathology requiring surgery after anterior cervical arthrodesis.

BACKGROUND CONTEXT: Postoperative malalignment of the cervical spine may alter cervical spine mechanics and put patients at risk for clinical adjacent segment pathology requiring surgery. PURPOSE: To investigate whether a relationship exists between cervical spine sagittal alignment and clinical adjacent segment pathology requiring surgery (CASP-S) following anterior cervical fusion (ACF). STUDY DESIGN: Retrospective matched study. PATIENT SAMPLE: A total of 122 patients undergoing ACF between 1996 and 2008 were identified, with a minimum of 2 years of follow-up. OUTCOME MEASURES: Radiographs were reviewed to measure the sagittal alignment using C2 and C7 sagittal plumb lines, distance from the fusion mass plumb line to the C2 and C7 plumb lines, the alignment of the fusion mass, caudally adjacent disc angle, the sagittal slope angle of the superior end plate of the vertebra caudally adjacent to the fusion mass, T1 sagittal angle, overall cervical sagittal alignment, and curve patterns by Katsuura classification. METHODS: A total of 122 patients undergoing ACF between 1996 and 2008 were identified, with a minimum of 1 year of follow-up. Patients were divided into groups according to the development of CASP (control/CASP-S) and by number/location of levels fused. Radiographs were reviewed to measure the sagittal alignment using C2 and C7 sagittal plumb lines, distance from the fusion mass plumb line to the C2 and C7 plumb lines, the alignment of the fusion mass, caudally adjacent disc angle, the sagittal slope angle of the superior end plate of the vertebra caudally adjacent to the fusion mass, T1 sagittal angle, overall cervical sagittal alignment, and curve patterns by Katsuura classification. Appropriate statistical tests were performed to calculate relationships between the variables and the development of CASP-S. No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this article. RESULTS: The groups were similar with regard to demographic and surgical variables. Lordosis was preserved in 82% (50/61) of the control group but in only 66% (40/61) of the CASP-S group (p=.033). More patients with a straight curve pattern developed CASP-S. The distance from the C2 to the C7 plumb line and T1 sagittal slope angle were lower in the CASP-S group with C5-C6 fusions compared with the control group. Also, the distance from C5-C6 fusion mass to C7 plumb line and C7 sagittal slope angle were lower in the CASP-S group with C5-C6 fusions. CONCLUSIONS: Our results suggest that malalignment of the cervical spine following an ACF at C5-C6 has an effect on the development of clinical adjacent segment pathology requiring surgery.

Surgical treatment of C3 and C4 cervical radiculopathies.

STUDY DESIGN: Case series study. OBJECTIVE: To report the results of surgical intervention in a series of patients with high cervical radiculopathy. SUMMARY OF BACKGROUND DATA: Although midcervical (C5-C7) radiculopathy is common and well recognized, high cervical (C3 and C4) radiculopathy is relatively rare and can be missed clinically. To our knowledge, there are few reports regarding the operative treatment of high cervical radiculopathy. METHODS: Two spine surgeons independently reviewed the charts and radiographs of all patients with high cervical radiculopathy or myeloradiculopathy that were surgically treated by the senior author. Dates of inclusion were from July 1997 to March 2008. All patients were observed for either a minimum of 2 years or until they achieved a fusion. Neck Disability Index scores were calculated pre- and postoperatively, when available, and Odom criteria were assessed for all patients. RESULTS: Twenty-three patients met the inclusion criteria. The mean follow-up period was 4.2 years (1-11.3 yr). The levels involved were C2-C3 (2 patients), C2-C4 (4 patients), and C3-C4 (17 patients). The most common symptom was suboccipital neck pain/headache with or without radiation to the retroauricular or retro-orbital region (21 patients). Preoperative neuroradiological findings were central stenosis with herniated nucleus pulposus, foraminal stenosis with uncinate hypertrophy or facet arthrosis, spondylolisthesis, and pseudarthrosis. Operative treatments included anterior cervical discectomy and fusion, posterior foraminotomy, posterior laminectomy-foraminotomy with fusion, posterior laminoplasty with fusion, and anterior/posterior combined decompression and fusion. By Odom criteria, 12 had excellent results, 8 had good results, 2 had satisfactory results, and 1 had a poor result. One patient underwent a reoperation for pseudarthrosis. CONCLUSION: Surgical treatment of high cervical radiculopathies resulted in acceptable outcomes. To our knowledge, this is the largest series of this relatively rare condition.

Elbow medial collateral ligament injuries.

Elbow medial collateral ligament sprain occurs when the elbow is subjected to a valgus force exceeding the tensile properties of the medial collateral ligament (MCL). This is an injury seen more often in throwing athletes. Understanding the differential diagnosis of medial elbow pain is paramount to diagnose MCL injury as well as addressing other medial elbow pathology. A natural evolution regarding MCL injury has occurred over the past 20 years, with modifications of the original surgical procedure, specificity and sensitivity analysis of imaging modalities, and physical exam maneuvers to diagnose MCL pathology. In order for the MCL literature to advance further, more biomechanical and long-term clinical outcome data for the respective surgical modifications are needed. This review describes MCL injury pathophysiology, patient evaluation, reconstruction indications/contraindications, and current and evolving surgical techniques.