Late-Onset Esophageal Perforation After Salvage Anterior Cervical Spine Surgery in a Patient With Systemic Sclerosis

Systemic sclerosis (SSc) is a systemic, immune-mediated disease characterized by abnormal cutaneous and organ-based fibrosis that results in progressive organ dysfunction including the esophagus. We herein report our experience of a patient with SSc who underwent salvage anterior cervical spine surgery that led to late-onset esophageal perforation. A 57-year-old female had progressive cervical kyphosis after laminoplasty for cervical spondylotic myelopathy. We performed anterior cervical discectomy and fusion using a stand-alone cage. Despite prolonged use of a neck collar, migration of the anterior cage was noted three months after surgery. Rapid progression of kyphotic deformity prompted us to perform revision surgery of circumferential cervical correction. However, conventional posterior surgery was precluded due to the extremely poor condition of her neck, including severely sclerotic skin and atrophic muscles. To address this, she underwent a posterior fusion with the closed technique and C4-C5 corpectomy and bone grafting using a low-profile anterior plate. One year after the surgery, CT and routine upper gastrointestinal endoscopy (UGE) showed no evidence of esophagus injury. She remained asymptomatic thereafter. Over three years after her last surgery, however, follow-up CT incidentally revealed an abnormal air leak around the anterior plate. UGE demonstrated large esophagus perforation with the exposed metal plate. As she had already been on parenteral nutrition due to the disease progression of SSc, we decided not to remove the implant. Potential esophagus perforation after anterior cervical spine surgery, even years later, should be considered regardless of the patient's symptoms, such as chest pain and dysphagia. Spine surgeons need to be cognizant of the fragility of the esophagus, especially in patients with SSc. For patients with SSc, posterior reconstruction alone is recommended as a relatively safe option, even with a suboptimal skin condition.

The influence of sagittal deformity of the distal radius on pronosupination: a cadaver study

We performed a cadaver study using seven fresh-frozen adult upper limbs to assess the impact of increasingly larger distal radial deformity in the sagittal plane on the range of motion in pronation/supination. Three palmar (20°, 30° and 40° angulations) and three dorsal (10°, 20° and 30° angulations) tilt deformities, without any radial shortening, were simulated by performing a radial osteotomy and using custom-made three-dimensional-printed anterior plates. We measured the maximum unconstrained pronation and supination before the osteotomy and after each induced deformation. There was a decrease in the median pronation and supination values for all palmar and dorsal tilt deformities. The pronation range was more impaired than the supination range, and dorsal tilt deformities caused the greatest loss in forearm rotation. Our results suggest that forearm rotation in both pronation and supination is reduced as soon as 10° to 20° distal radial deformity occurs in the palmar or dorsal direction.

Biomechanical effects of different lateral mass injury patterns on subaxial cervical fracture dislocations after anterior cervical surgery: a finite element study

OBJECTIVE

The lateral mass joint plays an important role in maintaining the mechanical stability of the subaxial cervical spine. We first performed a three-dimensional finite element (FE) biomechanical study to evaluate the local mechanical stability of subaxial cervical fracture dislocations after anterior-only fixation for lateral mass injuries of varying severity.

METHODS

A three-dimensional FE model of the subaxial cervical spine with simple anterior fixation for C5-6 fracture dislocation was reconstructed. According to their different morphological characteristics of unilateral lateral mass injuries, the lateral mass injury was divided into six types. The range of motion (ROM) of each part and the stress of the cage, each intervertebral disc, titanium plate, and screw stress were recorded.

RESULTS

The ROM of C3-4, C4-5, C5-6, and C6-7 in type 4 was higher than that of the other five types. The maximum equivalent stress on C4-5 intervertebral discs, titanium plates, and screws in type 4 under various sports loads was higher than that produced by the other load types. In the stress cloud diagram of the front titanium plate and screws, the degree of stress was the highest in type 4. Stress placed on each part of the model, from high to low, was as follows: plate, screw, C6, C5, and C7.

CONCLUSION

Greater injury severity is associated with higher stress on the plate and screw with exercise loads. Type 4 lateral mass injuries, characterized by ipsilateral pedicle and lamina junction fractures, significantly affected biomechanical stability after simple anterior fixation.

Use of zero-profile device for contiguous three-level anterior cervical discectomy and fusion: comparison with cage and plate construct

OBJECTIVE

The aim of this study was to compare a traditional cervical cage with a zero-profile (ZP) fixation device in patients who underwent three-level anterior cervical decompression and fusion (ACDF) in terms of patient-reported outcomes (visual analog scale [VAS], Japanese Orthopaedic Association [JOA], and Neck Disability Index [NDI] scores), radiographic findings (sagittal alignment 2 years after surgery and likelihood of fusion), and complications.

METHODS

This study was a retrospective case series. Between January 2012 and December 2016, 58 patients with cervical spondylotic myelopathy (CSM) who required three-level ACDF procedures, as identified by spinal surgeons, were treated with three-level ACDF and an anterior cage-plate construct (ACPC) (n = 38) or a three-level stand-alone ZP device (n = 20). On the basis of patient choice, patients were divided into two groups (ACPC group and ZP group). All patients completed a minimum of 2 years of follow-up. Patient-reported outcome scores included VAS, JOA, and NDI scores. The radiographic findings included sagittal alignment and likelihood of fusion 2 years after surgery. Data related to patient-reported outcomes and sagittal alignment were collected preoperatively, postoperatively, and at the final follow-up. Intraoperative and postoperative complications were also documented and analyzed.

RESULTS

The clinical outcomes, including VAS, JOA, and NDI scores, showed improvement in both groups, and no significant difference was observed between the two groups. Sagittal alignment and height of the fused segments were restored in all patients. However, the authors found no differences between the ZP and ACPC groups, and the groups exhibited similar fusion rates. The authors found no differences in complications, including dysphagia, adjacent-segment degeneration, and postoperative hematoma, between the groups.

CONCLUSIONS

Use of ZP implants yielded satisfactory long-term clinical and radiological outcomes that were similar to those of the standard ACPC. Additionally, the rates of complications between the groups were not significantly different. Although the best surgical option for multilevel CSM remains controversial, the results of this work suggest that ACDF with the ZP device is feasible, safe, and effective, even for multilevel CSM.

Comparison of Clinical and Radiographic Outcomes After Standalone Versus Cage and Plate Constructs for Anterior Cervical Discectomy and Fusion

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) has conventionally been performed using an allograft cage with a plate-and-screw construct. Recently, standalone cages have gained popularity due to theorized decreases in operative time and postoperative dysphagia. Few studies have compared these outcomes. Here, we directly compare the outcomes of plated versus standalone ACDF constructs.

METHODS

A single-center retrospective review of patients undergoing ACDF after June 2011 with at least 6 months of follow up was conducted. Clinical outcomes were analyzed and compared between standalone and plated constructs. Multivariate regression analysis of the primary outcome, need for revision surgery, as well as several secondary outcomes, procedure duration, estimated blood loss (EBL), length of hospital stay, disposition, and incidence of dysphagia, hoarseness, or surgical site infection, was completed.

RESULTS

A total of 321 patients underwent ACDF and met inclusion-exclusion criteria, with mean follow-up duration of 20 months. Forty-six (14.3%) patients received standalone constructs, while 275 (85.7%) received plated constructs. Fourteen (4.4%) total revisions were necessary, 4 in the standalone group and 10 in the plated group, yielding revision rates of 8.7% and 3.6%, respectively (P = .125). Mean EBL was 98 mL in the standalone group and 63 mL in the plated group (P = .001). Mean procedure duration was 147 minutes in the standalone group and 151 minutes in the plated group (P = .800). Mean hospital stay was 3.6 days in the standalone group and 2.5 days in the plated group (P = .270). There was no significant difference in incidence of dysphagia (P = .700) or hoarseness (P = .700).

CONCLUSIONS

Standalone ACDF demonstrates higher, but not statistically significant, revision rates than plate-and-screw constructs, without the hypothesized decreased incidence of dysphagia or hoarseness and without decreased procedure duration or EBL. Surgeons may consider limiting use of these constructs to cases of adjacent segment disease. Larger studies with longer follow up are necessary to make more definitive conclusions.

LEVEL OF EVIDENCE

4.

CLINICAL RELEVANCE

This study will help spine surgeons decide between using standalone or cage-and-plate constructs for ACDF.

Staged Treatment of Infected Tibiotalar Fusion Using a Combination Antibiotic Spacer and Antibiotic-Coated Intramedullary Nail

Pilon fractures are notoriously difficult injuries to treat. The current published data on salvage procedures after failed pilon fractures includes both total ankle arthroplasty (TAA) and tibiotalar fusion, each with its own specific indications. However, no acceptable treatment algorithm addressing the complications of these limb salvage procedures is available. We present the case of a 23-year-old patient, who sustained a complex pilon fracture after a motor vehicle accident. The patient was referred to our institution after an initial fixation attempt, followed by subsequent failed TAA, which was complicated by an infected fusion attempt. We describe a staged treatment approach to clearing the infection and obtaining the final fusion goals.

Integrated Fixation Cage Loosening Under Fatigue Loading

BACKGROUND

Screw loosening is a well-known adverse event in traditional spinal fusion instrumentation. This phenomenon may hinder segmental stability of the spine leading to bony non-union. In recent years numerous lumbar integrated fixation cages (IFC) have been introduced that offer a low profile alternative to a standard cage with an anterior plate (AP+C). The fixation approach for IFCs is different than a traditional anterior approach; therefore, it is unclear whether IFCs may loosen from the surrounding bone over time. The purpose of this study was to quantify screw loosening of IFC devices compared to AP+C implants under fatigue loading using micro-CT and image processing techniques.

METHODS

L2-3 and L4-5 functional spinal units (FSUs) were obtained from nine human lumbar spines. These FSUs were then reconstructed with either AP+C or IFC implants designed to attach to vertebral bodies using four screws (two top and two bottom for AP+C; two medial and two lateral for IFC). The reconstructed specimens were fatigued in flexion-extension load of ±3 Nm at 1Hz for first 5,000 cycles and it was increased to ±5 Nm until 20,000 cycles. After removing screws to prevent image artifact, micro-CT scans were performed on all FSUs post-fatigue. These images were post-processed to calculate three-dimensional volumes around screw holes created due to damage at the screw-implant interface.

RESULTS

IFC screws had significantly greater (p=0.008) screw hole volumes compared to AP+C screws after fatigue testing. This increased screw hole volume for IFC devices was mainly due to loosening in medial screws. Medial screws had significantly greater (p<0.003) screw hole volumes compared to lateral IFC screws and all AP+C screws. There was no difference (p>0.888) between the screw hole volumes of lateral IFC, top AP+C, and bottom AP+C screws.

CONCLUSIONS

This study elucidated screw-loosening mechanisms in integrated fixation cages under simulated physiological loading. In particular, spatial differences in fixation was observed for IFC screws across the vertebra where medial screws loosened at a greater frequency compared to lateral screws post-fatigue. This novel technique may also be used to quantitatively investigate screw fixation post-fatigue testing in a variety of spinal devices.

Anterior Cervical Discectomy and Fusion (ACDF): Comparison Between Zero Profile Implants and Anterior Cervical Plate and Spacer

Introduction: Interposition grafts combined with anterior plating currently remain the gold standard for anterior cervical discectomy and fusion. The use of anterior plates increases fusion rates but may be associated with higher rates of postoperative dysphagia. The aim of the current study was to determine the clinical and radiological outcomes following anterior cervical discectomy and fusion (ACDF) using zero-profile anchored spacers versus standard interposition grafts with anterior plating.

Methods: This was a retrospective case series. A total of 53 male and 51 female consecutive patients (164 total operated levels) who underwent ACDF between 2007 and 2011 were included. The mean clinical follow-up was 15.7 ± 1.2 (SEM) months for patients with zero-profile implants and 14.8 ± 2.1 months for patients with conventional ACDF with anterior plating. Patient demographics, operative details, clinical outcomes, complications, and radiographic imaging were reviewed. Dysphagia was determined using the Bazaz criteria.

Results: Clinical outcome scores improved in both groups as measured by the modified Japanese Orthopedic Association and Nurick scores. Zero-profile constructs gave rise to significantly less prevertebral soft tissue swelling compared to constructs with anterior plates postoperatively (15.74 ± 0.52 as compared to 20.48 ± 0.85 mm, p < 0.001) and at the latest follow-up (10.88 ± 0.39 mm vs. 13.72 ± 0.67 mm, p < 0.001). There was a significant difference in the incidence of dysphagia at the latest follow-up (1.5% vs. 20%, p=0.001, zero-profile vs. anterior plate, respectively).

Conclusion: Zero-profile implants lead to functional outcomes similar to standard anterior plate constructs. Avoiding the use of an anterior locking plate may decrease the risk of persistent postoperative dysphagia.