Effectiveness of bone substitute materials in opening wedge high tibial osteotomy: a systematic review and meta-analysis

Abstract

Background: A meta-analysis of eligible studies was performed to evaluate the effectiveness of bone substitute materials (BSMs) in opening wedge high tibial osteotomy (OWHTO) for knee osteoarthritis.

Methods: A systematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). A comprehensive literature search was performed, and studies comparing BSM with bone graft (BG) and without bone graft (WG) were included. The Cochrane risk of bias tool (version 1.0) and Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) tool were used to assess the risk of bias for randomized controlled trials (RCTs) and non-randomized studies (NRSs), respectively. The outcomes measured were the osteotomy gap size, the occurrence rates of non-union and lateral hinge fractures, knee functional score, infection and the Visual Analogue Scale (VAS). The quality of evidences was evaluated by Grades of Recommendation, Assessment, Development and Evaluation (GRADE) Working Group system.

Results: Five RCTs and eight NRS including 769 participants were included in our meta-analysis. The BSM group had a larger osteotomy gap size than the control group (MD: 0.41 mm, 95% confidence interval (CI): [0.06, 0.76], p=.02, I²=0%), with a significant difference. No significant difference was found between BSM and control group in main analysis in terms of bone non-union, but with a higher non-union rate when BSM combined with long locking plate was used. No significant differences were found in other outcome measures except for VAS from NRS subgroup. The quality of evidence for outcomes was low.

Conclusions: BSM combined with locking plate techniques offers a safe and efficient alternative option in OWHTO for osteotomy gap larger than 10 mm, but be aware of the possibility of bone non-union. Given the inherent heterogeneity and low quality of the included studies, future well-designed RCTs are essential to verify the findings.KEY MESSAGEThe treatment of the osteotomy gap is still controversial.BSM combined with a locking plate offers a safe and efficient alternative option for OWHTO with an over 10 mm of osteotomy gap over 10 mm.Due to the inherent heterogeneity and low quality of the included studies, the results should be cautiously interpreted in clinical practice.

Keywords: Knee osteoarthritis; bone substitute material; graft; opening wedge high tibial osteotomy.

Figure 1.

PRISMA flow diagram of studies identified, included and excluded.

Figure 2.

Summary of risk of bias. (A) Risk of bias for RCTs based on the Cochrane Collaboration tool (version 1.0). (B) Risk of bias for NRS based on ROBINS-I tool.

Figure 3.

Forest plot of comparison: osteotomy gap size between BSM and BG and WG groups after OWHTO. OWHTO: opening wedge high tibial osteotomy; KOA: knee osteoarthritis; CI: confidence interval; SD: standard deviation; BSM: bone substitute material; BG: bone graft; WG: without graft.

Figure 4.

Forest plot of the incidence of non-union in osteotomy gap filled with BSM and BG or WG. Subgroup analysis conducted by plate types (LLP and SLP). OWHTO: opening wedge high tibial osteotomy; KOA: knee osteoarthritis; CI: confidence interval; SD: standard deviation; BSM: bone substitute material; BG: bone graft; WG: without graft.

Figure 5.

Forest plot of secondary outcomes between BSM and BG and WG groups after OWHTO. (A) LHFs, (B) KSS, (C) infection and (D) VAS. OWHTO: opening wedge high tibial osteotomy; KOA: knee osteoarthritis; CI: confidence interval; SD: standard deviation; BSM: bone substitute material; BG: bone graft; WG: without graft; LHFs: lateral hinge fracture.