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Effect of Disc Height and Degree of Distraction on Heterotopic Ossification After Cervical Disc Replacement
Xiaofei Wang1, Hao Liu1, Yang Meng1
1Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu, China.
Insights
Preoperative disc height loss and postoperative distraction impact heterotopic ossification (HO) after cervical disc replacement (CDR). Identifying these factors can help reduce HO complications in CDR patients.
Area of Science:
- Spine surgery
- Orthopedics
- Biomaterials science
Background:
- Heterotopic ossification (HO) is a severe complication following cervical disc replacement (CDR).
- The precise mechanisms linking CDR, disc height loss (DHL), and postoperative distraction to HO remain incompletely understood.
- This study investigates the predictive value of preoperative DHL and postoperative distraction for HO development after CDR.
Purpose of the Study:
- To determine if preoperative disc height loss (DHL) and postoperative degree of distraction predict heterotopic ossification (HO) after cervical disc replacement (CDR).
- To establish quantitative thresholds for DHL and distraction that indicate an increased risk of HO.
- To evaluate the combined predictive value of DHL and distraction for HO development.
Main Methods:
- Analysis of lateral radiographs from 127 patients undergoing single-level CDR with a minimum 2-year follow-up.
- Measurement of preoperative disc height loss (DHL) and adjusted degree of distraction (ADD).
- Evaluation of HO occurrence and statistical analysis using receiver operating characteristic (ROC) curves to assess predictive values.
Main Results:
- Both DHL and ADD were significantly greater in patients who developed HO compared to those who did not (P < 0.05).
- DHL ≥24.97% increased HO risk by 5 times (P=0.003), and ADD ≥36.67% increased HO risk by 3.87 times (P<0.001).
- A combined parameter (DHL + ADD) cutoff of 60.36 demonstrated a sensitivity of 87.18% and specificity of 67.35% (AUC=0.77) for predicting HO.
Conclusions:
- Preoperative disc height loss (DHL) and postoperative distraction (ADD) are significantly associated with HO development after CDR.
- Specific cutoff values for DHL and ADD can help identify patients at higher risk for HO.
- The combined parameter offers a valuable tool for surgeons to optimize implant selection and minimize HO prevalence.
Background:
Heterotopic ossification (HO) is a potential and severe complication of cervical disc replacement (CDR). However, the underlying mechanism of CDR and its association with preoperative disc height loss (DHL) and postoperative degree of distraction remain unclear. We hypothesized that DHL and postoperative degree of distraction could predict HO after CDR.
Methods:
Data were obtained from 127 patients who underwent single-level CDR with a minimum follow-up of 2 years. DHL and adjusted degree of distraction (ADD) were obtained from lateral radiographs, and HO was evaluated at the last follow-up appointment. Receiver operating characteristic curves were calculated to verify the diagnostic value of DHL and ADD in predicting HO.
Results:
Both DHL and ADD were significantly larger in the HO group than in the non-HO group (P < 0.05). DHL ≥24.97% increased the risk of HO by 5 times (P = 0.003, 95% confidence interval 1.62-15.49), and ADD ≥36.67% increased the risk of HO by 3.87 times (P < 0.001, 95% confidence interval 1.81-8.27). A combined DHL and ADD (combined parameter) cutoff of 60.36 had a sensitivity of 87.18%, specificity of 67.35%, and area under the curve of 0.77 for predicting HO.
Conclusions:
DHL and ADD are associated with the development of HO after CDR. The cutoff value of DHL may narrow the criteria for CDR with the aim of reducing HO formation. The combined parameter may help surgeons to select the most suitable implant height to reduce the prevalence of HO.
