SLR - July 2022 - Ryan McGowan, DPM
Reference: Dilley JE, Everhart JS, Klitzman RG. Hyaluronic acid as an adjunct to microfracture in the treatment of osteochondral lesions of the talus: a systematic review of randomized controlled trials. BMC Musculoskelet Disord. 2022 Apr 2;23(1):313. doi: 10.1186/s12891-022-05236-6. PMID: 35366851; PMCID: PMC8976295.Level of Evidence: Level I Therapeutic
Reviewed By: Ryan McGowan, DPM
Residency Program: University Hospital - Newark, NJ
Podiatric Relevance:
An often overlooked injury seen by foot and ankle specialists is the osteochondral lesion of the talus (OLT). These injuries affect the articular cartilage layer and subchondral bone of the talus and frequently occur with ankle sprains and fractures. OLTs with fragmentation of bone in the tibiotalar joint that have failed conservative treatment warrant surgical intervention. A wide variety of treatment options have been described, with microfracture (MF) commonly used as a first line treatment due to its minimal invasiveness and low reported complications. Long term efficacy is questioned as MF leads to fibrocartilage regeneration rather than native hyaline cartilage. Hyaluronic Acid (HA) is a biologic compound that is produced in joints and is a major component of healthy synovial fluid, which can help restore this hyaline cartilage, as HA injections have been shown to be effective in treatment of osteoarthritis. This systematic review aims to analyze the results of high quality randomized controlled trials (RCTs) utilizing HA as an adjunct to MF as an intervention for OLT injuries with regard to functional outcomes when compared treatment using MF alone.
Methods:
A level I systematic review of literature across four databases (PubMed, SPORTDiscus, Scopus, and The Cochrane Library) was conducted for studies designed as RCTs using the American Orthopedic Foot and Ankle Society (AOFAS) Scale, Ankle/Hindfoot Scale (AHFS) and the Visual Analog Scale (VAS) as primary outcome measures for treatment groups. Three RCTs met this inclusion criteria, reviewing 132 total patients that underwent arthroscopic MF with or without HA injection. Baseline AOFAS/AHFS and VAS scores were pooled among studies, and then compared at final follow-up scores ranged from 10.5 to 25 months later. Statistical analysis of pooled data was compiled to evaluate functional and pain outcomes for treatment groups.
Results:
Patients in all treatment groups had significant improvement in both the AOFAS and VAS scores from baseline to final follow up. In the pooled analysis, there was a significant and moderate sized effect in favor of the HA in addition to MF treatment with regard to functional outcome, and a significant and large sized effect in regard to pain outcomes. The studies have some variance in the time to full weight-bearing as well as the timing of the HA injection administration, but overall results significantly favored treatment groups using HA in addition to MF.
Conclusions:
The magnitude of improvement in both pain and functional outcomes as a result of adding HA injections to MF treatment is clinically important. HA has already been shown to be an effective modality for treating osteoarthritis. The compilation of results from this review advocate for its usage in treatment of OLT. Literature has shown variable results in the many HA compounds available due to differences in molecular weight, viscoelasticity and other rheological properties. MF alone as a treatment often results in long term decline including post-traumatic arthritis. Long term results of HA in addition to MF need to be further investigated to build upon these optimistic short term findings.