# The effect of Proprioceptive Neuromuscular Facilitation (PNF) therapy on functional recovery in patients with knee joint injury: a systematic review and meta-analysis

## TL;DR

This study finds that PNF therapy improves knee function and reduces pain in patients with knee injuries.

## Contribution

The novel contribution is a meta-analysis showing PNF's effectiveness in knee recovery with specific intervention parameters.

## Key findings

- PNF improves knee flexion and extension range of motion in patients with knee injuries.
- PNF significantly reduces pain and enhances balance and daily living activities.
- Combined PNF interventions of 8–12 weeks, 5–7 sessions per week, are most effective for pain reduction.

## Abstract

This study employed a meta-analytic approach to systematically evaluate the effects of proprioceptive neuromuscular facilitation (PNF) therapy on functional recovery in patients with knee joint injuries.

Randomized controlled trials investigating the effects of PNF on functional recovery in patients with knee joint injuries were retrieved from the China National Knowledge Infrastructure, PubMed, Embase, Cochrane Library, and Web of Science databases. The methodological quality of the included studies was assessed using the Cochrane Risk of Bias Assessment Tool. Meta-analysis was performed using RStudio, Review Manager 5.4 and Stata 17 software. Pooled effect sizes were calculated as weighted mean differences (WMDs) or standardized mean differences (SMDs) with corresponding 95% confidence intervals (CIs) and 95% prediction intervals (PIs). Heterogeneity was evaluated using the I² statistic. A fixed-effects model was applied when I² ≤ 50%, whereas a random-effects model was used when substantial heterogeneity was present (I² > 50%).

A total of 13 studies involving 762 participants were included. PNF demonstrated significant benefits in patients with knee injuries, including improvements in knee flexion range of motion (WMD = 11.09, 95%CI: 4.60–17.57, 95%PI: -10.73–32.90), extension range of motion (WMD = 5.42, 95% CI: 1.29–9.56, 95%PI: -40.77–51.61), pain reduction (SMD = -0.93, 95% CI: -1.68 – -0.19, 95%PI: -4.01–2.14)), Lysholm Knee Scoring Scale scores (WMD = 13.96, 95% CI: 6.44–21.49, 95%PI: -17.63–45.55), Berg Balance Scale scores (WMD = 2.83, 95% CI: 0.49–5.17, 95%PI: -21.54–27.20), and Activities of Daily Living scores (SMD = 0.51, 95% CI: 0.12–0.91, 95%PI: -0.79–1.81). Subgroup analyses suggested that combined PNF interventions of 8–12 weeks, performed six times per week for 10–30 min per session, were associated with the greatest improvements in knee joint range of motion during traumatic or postoperative recovery. Similarly, the most pronounced reductions in pain were observed with combined PNF programs of 8–12 weeks, delivered 5–7 times per week for 10–30 min per session, were more effective in alleviating pain in this population.

PNF can significantly improve the active flexion range, extension range, pain, knee joint function, balance ability, and activities of daily living in patients with knee disorders. More high-quality studies with larger samples are still needed for further research.

The online version contains supplementary material available at 10.1186/s12891-025-09407-z.