MUA

What are the indications for an MUA?

An MUA (manipulation under anaesthesia) may be indicated when temporary stiffness is complicating recovery after knee injury or surgery. It is not relevant in long-standing stiffness of the knee, and may in these cases cause new damage.

• Quote from peer-reviewed paper:

  Stiffness can be defined "....as flexion contracture of > 15° and/or < 75° of flexion of the knee....[or]....an arc of knee motion < 70°."

  Citation: Mohammed R, Syed S, Ahmed N. Manipulation under anaesthesia for stiffness following knee arthroplasty. Ann R Coll Surg Engl. 2009 Apr;91(3):220-3. doi: 10.1308/003588409X359321. Epub 2008 Dec 19. PMID: 19102828; PMCID: PMC2765009.

• Quote from peer-reviewed paper:

  Up to 60° of flexion is needed for limpless walking on level ground [4], at least 83° of flexion is needed to climb stairs, and 93° flexion is necessary to sit comfortably"

  Citation: Randsborg PH, Tajet J, Negård H, Røtterud JH. Manipulation under Anesthesia for Stiffness of the Knee Joint after Total Knee Replacement. Arthroplast Today. 2020 Jun 28;6(3):470-474. doi: 10.1016/j.artd.2020.05.019. PMID: 32637518; PMCID: PMC7329891.

Back to top

What happens during an MUA?

An MUA allows the surgeon an opportunity to break adhesions in a joint that has recently been injured or operated on, and where stiffness has become a problem due to sticky adhesions locking up the tissue folds inside the joint. The patient is given a general anaesthetic, possibly with some muscle relaxation, and the surgeon gently rocks the joint through flexion, extension and rotation, trying with each effort to gain a few more degrees of range of motion. The anaesthetic is to ensure complete relaxation without pain interfering with the process.

After the procedure physiotherapy is re-instituted and continuous passive motion (CPM)

• Quote from peer-reviewed paper:

  Under adequate muscle relaxation....[the hip is flexed]....to 90°. With the leg held close to the knee joint (to decrease the lever arm), steady progressive loading was applied till palpable and audible break of adhesions were heard....no further pressure was applied."

  Citation: Mohammed R, Syed S, Ahmed N. Manipulation under anaesthesia for stiffness following knee arthroplasty. Ann R Coll Surg Engl. 2009 Apr;91(3):220-3. doi: 10.1308/003588409X359321. Epub 2008 Dec 19. PMID: 19102828; PMCID: PMC2765009.

Back to top

How effective is MUA?

There are a lot of variables when making the decision to perform an MUA, such as timing from the injury or surgery, age, sex, smoking, diabletes, experience of the surgeon - and different countries and establishments will follow different practices.

• Quote from peer-reviewed paper:

  The large variation in the incidence of MUA after primary TKA indicates that there are believers and nonbelievers among knee surgeons as regards the value of MUA."

  Citation: W-Dahl A. Manipulation under anesthesia: to do or not to do, that is the question. Acta Orthop. 2022 Jul 15;93:682-683. doi: 10.2340/17453674.2022.4344. PMID: 35848730; PMCID: PMC9290212.

Back to top

Forum discussions

• AF for 4 years + an unsuccessful LOA. Is there any hope for me?

  Patients discussing the timing of MUA when the knee has been stiff for some time.

Back to top