Impairments and rehabilitation outcomes in patients with traumatic meniscal tears and meniscectomy

Traumatic meniscal tears often occur during sports activities. Many patients receive meniscectomy to re-establish normal knee function and facilitate return to sport participation. However, quadriceps weakness is a common impairment after meniscectomy. As quadriceps weakness is related to poor knee function and articular cartilage degradation, restoring quadriceps strength after meniscectomy is imperative. In addition, psychosocial factors can be altered after knee injury. The overall goal of this dissertation was to compare the effects of targeted quadriceps strengthening and standard rehabilitation on knee function and impairments over 1-year after meniscectomy, to explore the interaction between quadriceps strength and psychosocial factors after meniscectomy, and to examine the contributions of quadriceps strength and psychosocial factors to function and movement patterns of the knee. No differences were found between the targeted quadriceps strengthening group and standard rehabilitation group in self-reported knee function, tibial cartilage volume and defect score, and quadriceps impairments. Pain catastrophizing and fear of movement/re-injury improved from pre-surgery to post-intervention. Pre-surgical pain catastrophizing was positively associated with knee pain at 1-year post-surgery. Pre-surgical fear of movement/re-injury was positively associated with knee function at 1-year post-surgery in the targeted quadriceps strengthening group, but negatively associated with knee function at 1-year post-surgery in standard rehabilitation group. In both groups combined, the surgical limb showed reduced knee flexion excursion compared to the non-surgical limb during the weight acceptance phase of gait, and the change in pain catastrophizing was negatively associated with the change in peak vertical ground force from pre-surgery to post-intervention. In addition, the surgical limb showed reduced peak knee flexion angle and knee extension moment compared to the non-surgical limb during the landing phase of a single leg hop. Rate of knee extensor torque development was positively associated with single leg hop performance, as well as the peak knee flexion angle and knee extension moment. Self-efficacy for knee activity was also positively associated with single leg hop performance. In summary, the targeted quadriceps strengthening intervention did not result in better knee function and less impairments. Psychosocial factors and rate of knee extensor torque development may influence functional performance and movement patterns after meniscectomy.