Complications and Complication Avoidance With Cervical Total Disc Replacement

Complications with cervical arthroplasty can be generalized to errors in patient selection or surgical technique. Patients with advanced spondylosis or osteophytic disease, severe facet arthropathy, osteoporosis, sagittal deformity, or preoperative instability are poor candidates for arthroplasty and are more prone to complications. Poor surgical technique can result in subsidence, expulsion, and kyphosis, and it can contribute to heterotopic ossification. Additionally, all of the inherent complications from an anterior cervical approach may occur with cervical artificial disc placement. This article will focus on the complications uniquely associated with cervical arthroplasty.

Efficacy and safety of Mobi-C cervical artificial disc versus anterior discectomy and fusion in patients with symptomatic degenerative disc disease: A meta-analysis

BACKGROUND

Total disc replacement (TDR) using Mobi-C cervical artificial disc might be promising to treat symptomatic degenerative disc disease. However, the results remained controversial. We conducted a systematic review and meta-analysis to compare the efficacy and safety of Mobi-C cervical artificial disc and anterior cervical discectomy and fusion (ACDF) in patients with symptomatic degenerative disc disease.

METHODS

PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases were systematically searched. Randomized controlled trials (RCTs) assessing the effect of Mobi-C versus ACDF on the treatment of symptomatic degenerative disc disease were included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. The primary outcomes were neck disability index (NDI) score, patient satisfaction, and subsequent surgical intervention. Meta-analysis was performed using the random-effect model.

RESULTS

Four RCTs were included in the meta-analysis. Overall, compared with ACDF surgery for symptomatic degenerative disc disease, TDR using Mobi-C was associated with a significantly increased NDI score (Std. mean difference = 0.32; 95% CI = 0.10-0.53; P = .004), patient satisfaction (odds risk [OR] = 2.75; 95% confidence interval [CI] = 1.43-5.27; P = .002), and reduced subsequent surgical intervention (OR = 0.20; 95% CI = 0.11-0.37; P < .001). Mobi-C was found to produce comparable neurological deterioration (OR = 0.77; 95% CI = 0.35-1.72; P = .53), radiographic success (OR = 1.18; 95% CI = 0.39-3.59; P = .77), and overall success (OR = 2.13; 95% CI = 0.80-5.70; P = .13) compared with ACDF treatment.

CONCLUSION

Among the 4 included RCTs, 3 articles were studying patients with 1 surgical level, and 1 article reported 2 surgical levels. When compared with ACDF surgery in symptomatic degenerative disc disease, TDR using Mobi-C cervical artificial disc resulted in a significantly improved NDI score, patient satisfaction, and reduced subsequent surgical intervention. There was no significant difference of neurological deterioration, radiographic success, and overall success between TDR using Mobi-C cervical artificial disc versus ACDF surgery. TDR using Mobi-C cervical artificial disc should be recommended for the treatment of symptomatic degenerative disc disease.

Cervical artificial disc extrusion after a paragliding accident

Background:

Cervical total disc replacement (TDR) is an established alternative to anterior cervical discectomy and fusion (ACDF) with excellent long-term outcomes and low failure rates. Cases of implant failure and migration are scarce and primarily limited to several years postoperatively. The authors report a case of anterior extrusion of a C4-C5 ProDisc-C (DePuy Synthes, West Chester, PA, USA) cervical artificial disc (CAD) 14 months after placement due to minor trauma.

Case Description:

A 33-year-old female who had undergone C4-C5 CAD implantation presented with neck pain and spasm after experiencing a paragliding accident. A 4 mm anterior protrusion of the CAD was seen on x-ray. She underwent removal of the CAD followed by anterior fusion. Other cases of CAD extrusion in the literature are discussed and the device's durability and testing are considered.

Conclusion:

Overall, CAD extrusion is a rare event. This case is likely the result of insufficient osseous integration. Patients undergoing cervical TDR should avoid high-risk activities to prevent trauma that could compromise the disc's placement, and future design/research should focus on how to enhance osseous integration at the interface while minimizing excessive heterotopic ossification.

Biomechanical analysis of single- and double-level cervical disc arthroplasty using finite element modeling

Recently, many different types of artificial discs have been introduced to persevere the biomechanical behavior of the cervical spine. This study compares the biomechanical behavior of single- and double-level cervical disc arthroplasty, that is "Prestige LP and Mobi-C" on the index and adjacent segment. A three-dimension finite element model of C2-C7 was developed and validated. In single-level prostheses, the Prestige LP or Mobi-C was implanted in the segment C5-C6, while the double-level arthroplasty was integrated at both segments C4-C5 and C5-C6 in the FE model. The intact FE and prosthesis-modified models were constrained from the inferior endplate of the vertebra C7 and applied a compressive load of 73.6 N with a moment load of 1 Nm on the odontoid process of the vertebra C2 to produce flexion/extension, lateral bending, and axial rotation. The prosthesis-modified model's range of motion and intradiscal pressure were determined and compared to the intact model. Also examined the impact of the prostheses on the stress at the bone-implant interface. The range of motion of the implanted segments in both single- and double-levels arthroplasty was increased while that of the adjacent segment of implanted segments decreased. The intradiscal pressure in both levels of arthroplasty was greater than in the intact model. In conclusion, Mobi-C's cervical prostheses could better preserve the normal range of motion and maintain intradiscal pressure than the Prestige LP.

Myelopathy after cervical disc arthroplasty due to progression of spondylosis at the index level: case report

Cervical disc arthroplasty (CDA) has emerged as a popular alternative to anterior cervical discectomy and fusion (ACDF) for the surgical treatment of cervical degenerative disc disease. CDA has been well studied, with efficacy reported to be equivalent to or better than that seen with ACDF, and it is associated with a consistently low incidence of adverse events. The development or progression of myelopathy after CDA is a particularly rare occurrence. In this report, the authors describe the first known case of recurrence of myelopathy at the index level of surgery after CDA implantation due the continuation of the spondylitic process after placement of the artificial disc.