Authors: Daniel G. Cobian, DPT, PhD, CSCS

Study Design
Descriptive, prospective single-cohort longitudinal study.

Background
Rapid torque development is essential in activities of daily living and sports, but isn’t specifically tested by most physical therapists or incorporated into rehabilitation programs until late in the treatment process. Little evidence is available on quadriceps rate of torque development capacity before and after arthroscopic knee surgery.

Objectives
To study knee extensor rate of torque development, contributing mechanisms, and associations with strength and patient-reported outcomes, before and during the first six weeks after arthroscopic partial meniscectomy.

Methods
Twenty subjects (age 42.3 ± 13.7, BMI 26.6 ± 3.1 kg/m2) were tested before and about two and five weeks after surgery. Quadriceps muscle volume, strength, activation, rate of torque development, and patient-reported outcomes were evaluated at each interval and across the study period.

Results
Significant side-to-side differences in quadriceps strength and voluntary rate of torque development were observed at each time point (P<.05). Changes in muscle activity were associated with changes in rapid torque development capacity. Side-to-side rate of torque development deficits after surgery were associated with lower patient-reported outcomes scores. Conclusion Diminished rapid torque development capacity is common in arthroscopic meniscal debridement patients. This reduced capacity is associated with an inability to quickly recruit and drive the quadriceps muscles (neural mechanisms) and not muscle atrophy or other peripheral factors tested. Patient-reported outcomes are associated with quadriceps rate of torque development, but not strength or muscle size. Rapid torque development warrants greater attention in rehabilitation. J Orthop Sports Phys Ther, Epub 9 Oct 2017. doi:10.2519/jospt.2017.7310 Journal Reference