Muscle recovery following knee arthroplasty

Investigators assessed changes in quadriceps and hamstring strength and flexibility through 12 months following total knee arthroplasty.

Category	Detail
Condition	Knee osteoarthritis
Key Mechanisms	Quadriceps and hamstring strength and flexibility decline post-surgery, with gradual recovery but persistent deficits.
Target Population	Patients aged 50 to 80 years with primary, severe Kellgren-Lawrence grade 4 knee osteoarthritis.
Care Setting	Postoperative rehabilitation following total knee arthroplasty.

Quadriceps strength decreased from 12 lbs preoperatively to 7 lbs at 6 weeks, then increased to 43 lbs at 12 months.
Hamstring strength decreased from 20 lbs preoperatively to 13 lbs at 6 weeks, then increased to 58 lbs at 12 months.
At 12 months, quadriceps and hamstring strength remained lower compared to healthy controls.
Standardized postoperative rehabilitation included progressive strengthening, mobility, stretching, functional training, balance training, and aerobic conditioning.
Persistent quadriceps deficits at 12 months suggest potential inadequacy of conventional rehabilitation programs.

Evaluate strength and flexibility preoperatively and at multiple postoperative intervals.

Assess muscle strength and flexibility at 6 weeks, 3 months, 6 months, and 12 months post-surgery.

Attrition at 12 months may limit generalizability; absence of blinded outcome assessment may introduce bias.

Patients undergoing total knee arthroplasty due to severe knee osteoarthritis.

Rehabilitation programs may need to be adjusted to address persistent muscle function deficits.

Conduct regular assessments of quadriceps and hamstring strength post-surgery.
Tailor rehabilitation programs to address specific deficits observed in muscle strength.