The Osteoarthritis Research Society International recommends evaluating physical function in gonarthrosic patients after a total knee arthroplasty using tests such as timed up and go (TUG) and six-minute walking test (6MWT). In 1991, Berman et al. found that strength was not fully recovered until two years after surgery.

Our aim was to demonstrate the results in physical function and isokinetic muscular strength of gonarthrosis patients prior to undergoing surgery and three months after a total knee arthroplasty (TKA).

Prospective study (September 2016–December 2017) of patients with gonarthrosis awaiting a total knee arthroplasty surgery. Variables recorded: gender, age, dominant hand, operated side, body mass index (BMI), walking aids. Measured outcomes before surgery and three months afterwards: Visual Analogue Scale (VAS) at rest and active, TUG, 6MWT and mean peak torque (PT) of isokinetic strength of quadriceps and hamstrings between the TKA side and the unaffected knee at 60°/s. Data analysis of means and percentages. Means compared using Student t and non-parametric tests. Statistical significance was set at P<0.05.

Forty-four patients, 36.4% male. Mean age 67.8±6.5. Mean BMI 30.3±6.7; 63.6% of the individuals used walking aids before surgery and 84.1% did not use them after surgery. The results obtained on VAS and physical function prior to surgery and three months after the intervention were. A decrease of strength in the affected quadriceps and a significant decrease of strength in the affected hamstrings were observed. However the strength of the unaffected quadriceps increased slightly and the unaffected hamstrings strength did not vary.

Three months after a TKA surgery, even though there was a descent in muscular strength in the affected limb, our patients experienced an improvement in physical function possibly due to pain decrease.