Exploring the Link Between Manipulation Under Anesthesia and Revision Surgery
An Insight into the Potentially Disruptive Complication Associated with Manipulation Under Anesthesia Following Total Knee Arthroplasty.
Knee replacement surgery is a frequent and successful procedure, with over 100,000 cases done annually in the United Kingdom alone. The primary objectives of total knee arthroplasty (TKA) are pain alleviation and knee function improvement, and post-operative range of motion is one of the numerous parameters that may influence patient satisfaction following TKA.1
Eighty to eighty-five to ninety-five per cent of patients have a good result and an enhanced quality of life. In general, the functional range of motion of the knee is considered to be 0°–90°, as this allows the patient to sit in a chair with the knee flexed and utilize stairs without difficulty. Studies show that gait and slopes require less than 90 degrees of knee flexion, stairs and chairs 90–120 degrees of flexion and a bath approximately 135 degrees of flexion. The data suggests that 110 degrees of flexion would seem a suitable goal for the rehabilitation of motion in the knee. The majority of patients may obtain ROM arcs within 10°–15° of their pre-operative values. As was previously stated, around 80% to 85% of persons achieve their targeted goals2.
However, not everything is rainbows and sunshine. Despite being a highly popular surgical procedure with great results, stiffness in the knee joints after surgery is a typical consequence that affects around 15 to 20% of the population. A limited range of motion below functional criteria can reduce the patient’s ability to conduct daily activities, potentially resulting in unhappiness with the knee joint. Several studies have looked into what characteristics increase the likelihood of developing post-operative joint stiffness after TKA, and common ones include being overweight, being under the age of 65, smoking, and having a smaller pre-operative range of motion3,4.
To combat the issue of post-operative stiffness following knee arthroplasty, manipulation under anesthesia (MUA) is frequently used. Within the first six months following the MUA, this minimally invasive technique has been proven to enhance functional outcomes5. Range of motion after TKA surgery may plateau early on, but this technique can help break through that barrier. The result has typically been more knee flexion and happier patients in the long run. Whether post-operative MUA necessitates an increased risk for revision TKA is one of many potential complications that have not yet been adequately defined. The cost of revision TKA is high for the patient and the healthcare system as a whole. Also, the outcomes are worse for patients who require a second TKA due to post-operative stiffness6.
1.51% of patients within 90 days postoperatively and 4.9% of patients within two years postoperatively have been documented to undergo MUA following TKA7. Patients younger than 40 and with a lower body mass index have been identified in the research to be more likely to undergo MUA. In addition to smokers and people of African American and female gender, those who have been the subject of a revision have been found to have a greater chance of requiring an MUA.
Various studies have documented the risk of requiring a revision surgery following MUA. Werner reported that the risk of needing revision surgery was 2.4 times higher in patients who underwent MUA compared to patients who did not require MUA. There has been no shortage of conflicting evidence as well. A cohort study published in 2012 showed that of the 48 patients who underwent MUA after TKA, only one patient required revision surgery at 7.5 years follow-up.
Despite the risk of revision surgery, MUA has been an important tool for orthopedic surgeons dealing with stiffness post-total knee arthroplasty. Studies have suggested that MUA has improved flexion by 22 degrees to 39 degrees and extension by an average of 2 to 5 degrees in patients who suffered stiffness post-TKA. This clearly shows that the importance of MUA cannot and should not be ignored due to a risk of revision, a risk that is present but has not been fully established. This begets the question of what should be done to minimize this risk.
One of the essential aspects is patient education. The patients should be informed of the recent research and aware that MUA, albeit associated with a slight risk of revision surgery, carries a far greater benefit in the long run. We have already stated earlier that younger patients tend to have a greater risk of revision surgery. The authors hypothesized that higher patient expectations and the need for more post-operative flexibility in younger patients may be to blame for the higher rate observed in this demographic.
In conclusion, after a total knee replacement, there is a small increase in the likelihood of revision if an MUA is performed. Despite this, the value and significance of MUA in the clinic cannot be overstated. Not to mention, satisfactory clinical and functional outcomes may still be achieved if an MUA and even a subsequent revision arthroplasty are required
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References
1. Choi YJ. Patient satisfaction after total knee arthroplasty. Knee Surgery & Related Research (구 대한슬관절학회지). 2016;28(1):1-5.
2. Choi HR, Siliski J, Malchau H, Freiberg A, Rubash H, Kwon YM. How often is functional range of motion obtained by manipulation for stiff total knee arthroplasty?. International orthopaedics. 2014 Aug;38(8):1641-5.
3. Issa K, Rifai A, Boylan MR, Pourtaheri S, McInerney VK, Mont MA. Do various factors affect the frequency of manipulation under anesthesia after primary total knee arthroplasty?. Clinical Orthopaedics and Related Research®. 2015 Jan;473(1):143-7.
4. Pfefferle KJ, Shemory ST, Dilisio MF, Fening SD, Gradisar IM. Risk factors for manipulation after total knee arthroplasty: a pooled electronic health record database study. The Journal of arthroplasty. 2014 Oct 1;29(10):2036-8.
5. Gu A, Michalak AJ, Cohen JS, Almeida ND, McLawhorn AS, Sculco PK. Efficacy of manipulation under anesthesia for stiffness following total knee arthroplasty: a systematic review. The Journal of arthroplasty. 2018 May 1;33(5):1598-605.
6. Keeney JA, Clohisy JC, Curry M, Maloney WJ. Revision total knee arthroplasty for restricted motion. Clinical Orthopaedics and Related Research®. 2005 Nov 1;440:135-40.7. Pfefferle KJ, Shemory ST, Dilisio MF, Fening SD, Gradisar IM. Risk factors for manipulation after total knee arthroplasty: a pooled electronic health record database study. The Journal of arthroplasty. 2014 Oct 1;29(10):2036-8.
