ACL reconstruction vs rehab

https://pubmed.ncbi.nlm.nih.gov/38940695/

ACL SNNAP Trial (Beard et al., 2022)

Rehabilitation versus ACL Reconstruction for Persistent Instability

Beard DJ, Davies L, Cook JA, Stokes J, Leal J, Fletcher H, Abram S, Chegwin K, Greshon A, Jackson W, Bottomley N, Dodd M, Bourke H, Shirkey BA, Paez A, Lamb SE, Barker K, Phillips M, Brown M, Lythe V, Mirza B, Carr A, Monk P, Morgado Areia C, O’Leary S, Haddad F, Wilson C, Price A; ACL SNNAP Study Group. Rehabilitation versus surgical reconstruction for non-acute anterior cruciate ligament injury (ACL SNNAP): a pragmatic randomised controlled trial. Lancet. 2022 Aug 20;400(10352):605-615. doi: 10.1016/S0140-6736(22)01424-6. PMID: 35988569.

Key Points

  • This large UK randomised controlled trial compared surgery versus physiotherapy for ACL injuries that had not settled over time
  • Patients who had ACL reconstruction had better outcomes at 18 months
  • Surgery improved knee function by around 8 points more on a validated outcome score
  • Around 30% of patients initially treated with physiotherapy eventually required surgery
  • Complication rates were low and similar between both groups
  • Surgery was also found to be cost-effective in the NHS setting

What was studied?

This was a high-quality multicentre trial involving 316 patients across 29 NHS hospitals in the UK

All patients had:

  • An ACL injury that was no longer acute
  • Ongoing symptoms such as instability or the knee “giving way”

They were randomly assigned to:

  • ACL reconstruction surgery
  • Structured rehabilitation (physiotherapy), with surgery later if needed

What were the results?

Overall improvement

Both groups improved, but surgery gave better outcomes:

  • Surgery group improved from ~46 to 73
  • Rehabilitation group improved from ~43 to 65

This represents:

  • An average advantage of 7.9 points for surgery
  • A statistically and clinically meaningful difference

Need for later surgery

A key finding was how many patients needed delayed surgery:

  • 31% of patients in the physiotherapy group went on to have ACL reconstruction
  • Patients who eventually had surgery ended up with similar outcomes to those who had early surgery, but took longer to improve

This highlights that:

  • Physiotherapy alone works well for some patients
  • But many will still require surgery to restore stability

Symptoms, function, and activity

Across multiple measures, surgery performed better:

  • Less pain
  • Better knee function
  • Higher activity levels
  • Better quality of life scores

Patient satisfaction was also higher:

  • 83% of surgical patients felt their knee was better
  • Compared to 68% in the rehabilitation group

Return to sport

Return to pre-injury sport was limited in both groups:

  • 28% after surgery
  • 24% after rehabilitation

This reflects the challenging nature of ACL injuries, regardless of treatment

Safety and cost

  • Complication rates were low and similar between groups
  • Surgery was more expensive upfront but considered cost-effective overall
  • There were no major safety concerns identified

What does this mean for patients?

For patients with ongoing instability after an ACL injury:

  • ACL reconstruction is more likely to restore stability and function
  • Physiotherapy is still a valid first approach, particularly for less demanding activity levels
  • However, many patients may ultimately need surgery

The decision should be individual, based on:

  • Activity level and sporting goals
  • Degree of instability
  • Personal preferences