# Network meta-analysis of high tibial osteotomy combined with different bone defect filler materials for medial compartment knee osteoarthritis

## TL;DR

This study compares different bone filler materials used with high tibial osteotomy for knee osteoarthritis, finding autografts effective but risky, while synthetic and allografts offer better balance.

## Contribution

A network meta-analysis comparing various bone defect filler materials in high tibial osteotomy for knee osteoarthritis.

## Key findings

- Autogenous iliac bone grafting shows superior efficacy but has higher donor site morbidity.
- Synthetic grafts and allografts provide a more favorable risk-benefit profile.
- Outcomes like WOMAC score and lateral cortical fracture favor synthetic and allografts.

## Abstract

This study aims to systematically review and analyze the clinical and radiographic outcomes of high tibial osteotomy (HTO) combined with various bone defect filler materials for the treatment of medial compartment knee osteoarthritis (MCKOA). In light of the increasing adoption of enhanced recovery after surgery (ERAS) principles, we further seek to refine treatment strategies for MCKOA by comparing the therapeutic effects of different filler materials.

We performed a comprehensive literature search of studies published from database inception to July 1, 2024, across PubMed, Medline, Embase, the Cochrane Library, Web of Science, and Scopus. Using a network meta-analysis framework, we systematically assessed clinical comparative studies involving two or more bone defect filler materials in patients undergoing medial open-wedge high tibial osteotomy. Evidence was synthesized through a Bayesian random-effects network meta-analysis. Methodological quality and risk of bias of included studies were evaluated using the Cochrane Risk of Bias Tool 2.0 and a modified Newcastle–Ottawa scale.

After rigorous screening, 29 eligible trials were identified from 2755 references, including 10 randomized controlled trials (RCTs) and 19 non-randomized comparative trials (NCTs), involving a total of 1549 participants. These trials evaluated six intervention types: autografts, allografts, synthetic grafts, composite grafts, xenografts, and no grafts. Analyses based on outcomes such as clinical bone healing time, percentage of complete bone union, Lysholm knee score, infection, and delayed union, autogenous iliac bone grafting showed potential as a favorable option. However, considering correction of osteotomy defects and donor site morbidity, autogenous iliac bone grafting should be avoided. In contrast, synthetic grafts or allografts appeared more favorable when assessed using outcomes like WOMAC score, lateral cortical fracture, and donor site morbidity.

Taking into account postoperative prognosis and complication profiles in HTO patients, autogenous iliac bone grafting may demonstrates superior efficacy in treating MCKOA, though its associated risks warrant careful consideration. Synthetic grafts and allografts offer a more balanced risk–benefit profile and represent recommended alternatives.

Level III, a meta-analysis of Level I RCTs and Level II-III non-randomized controlled trials.

The online version contains supplementary material available at 10.1186/s13018-025-06306-w.