and patients with PFP report increased fear-avoidance beliefs in addition to deficits in self-reported knee function. 13 , 14 Research suggests that there may be an association between psychological impairments and subjective appraisal of knee function. 5 There is moderate evidence to support that
Francesca Genoese, Shelby Baez and Johanna M. Hoch
Lori A. Bolgla and Douglas R. Keskula
To provide information on research investigating the relationship between a knee effusion and quadriceps inhibition
Peer-reviewed publications from 1965 to 1997 that investigated the effect of a knee effusion on quadriceps strength.
The studies reviewed involved human subjects. Researchers have used active motion, electromyographic equipment, and isokinetics to measure changes in quadriceps strength after a knee effusion.
Most studies reported that a knee effusion resulted in quadriceps inhibition and inferred that quadriceps inhibition would impair knee function.
The authors believe that additional research is needed to better understand the effect of a knee effusion on knee function. Although a knee effusion might lead to quadriceps inhibition, other factors contribute to normal knee function and might allow enough compensation so that knee function is not affected significantly in the presence of certain effusions.
Andrew E. Littmann, Masaki Iguchi, Sangeetha Madhavan, Jamie L. Kolarik and Richard K. Shields
There is conflicting evidence in the literature regarding whether women with anterior cruciate ligament reconstruction (ACLR) demonstrate impaired proprioception. This study examined dynamic-position-sense accuracy and central-nervous-system (CNS) processing time between those with and without long-term ACLR.
To compare proprioception of knee movement in women with ACLR and healthy controls.
Human neuromuscular performance laboratory.
11 women (age 22.64 ± 2.4 y) with ACLR (1.6–5.8 y postsurgery) and 20 women without (age 24.05 ± 1.4 y).
The authors evaluated subjects using 3 methods to assess position sense. During knee flexion at pseudorandomly selected speeds (40°, 60°, 80°, 90°, and 100°/s), subjects indicated with their index finger when their knee reached a predetermined target angle (50°). Accuracy was calculated as an error score. CNS processing time was computed using the time to detect movement and the minimum time of angle indication. Passive and active joint-position sense were also determined at a slow velocity (3°/s) from various knee-joint starting angles.
Main Outcome Measurements:
Absolute and constant error of target angle, indication accuracy, CNS processing time, and perceived function.
Both subject groups showed similar levels of error during dynamic-position-sense testing, despite continued differences in perceived knee function. Estimated CNS processing time was 260 ms for both groups. Joint-position sense during slow active or passive movement did not differ between cohorts.
Control and ACLR subjects demonstrated similar dynamic, passive, and active joint-position-sense error and CNS processing speed even though ACLR subjects reported greater impairment of function. The impairment of proprioception is independent of post-ACLR perception of function.
Pia Thomeé, Peter Währborg, Mats Börjesson, Roland Thomeé, Bengt I. Eriksson and Jon Karlsson
The Knee Self-Efficacy Scale (K-SES) has good reliability, validity, and responsiveness for patients’ perceived knee-function self-efficacy during rehabilitation after an anterior cruciate ligament (ACL) injury. Preoperative knee-function self-efficacy has also been shown to have a predictive ability in terms of outcome 1 y after ACL reconstruction.
To evaluate a new clinical rehabilitation model containing strategies to enhance knee-function self-efficacy.
A randomized, controlled study.
Rehabilitation clinic and laboratory.
40 patients with ACL injuries.
All patients followed a standardized rehabilitation protocol. Patients in the experimental group were treated by 1 of 3 physiotherapists who had received specific training in a clinical rehabilitation model. These physiotherapists were also given their patients’ self-efficacy scores after the initial and 4-, 6-, and 12-mo follow-ups, whereas the 5 physiotherapists treating the patients in the control group were not given their patients’ self-efficacy scores.
Main Outcome Measures:
The K-SES, the Tegner Activity Scale, the Physical Activity Scale, the Knee Injury and Osteoarthritis Outcome Score, and the Multidimensional Health Locus of Control.
Twenty-four patients (12 in each group) completed all followups. Current knee-function self-efficacy, knee symptoms in sports, and knee quality of life improved significantly (P = .05) in both groups during rehabilitation. Both groups had a significantly (P = .05) lower physical activity level at 12 mo than preinjury. No significant differences were found between groups.
In this study there was no evidence that the clinical rehabilitation model with strategies to enhance self-efficacy resulted in a better outcome than the rehabilitation protocol used for the control group.
Christopher A. Bailey and Patrick A. Costigan
The step-up-and-over test has been used successfully to examine knee function after knee injury. Knee function is quantified using the following variables extracted from force plate data: the maximal force exerted during the lift, the maximal impact force at landing, and the total time to complete the step. For various reasons, including space and cost, it is unlikely that all clinicians will have access to a force plate. The purpose of the study was to determine if the step-up-and-over test could be simplified by using an accelerometer. The step-up-and-over test was performed by 17 healthy young adults while being measured with both a force plate and a 3-axis accelerometer mounted at the low back. Results showed that the accelerometer and force plate measures were strongly correlated for all 3 variables (r = .90–.98, Ps < .001) and that the accelerometer values for the lift and impact indices were 6–7% higher (Ps < .01) and occurred 0.07–0.1 s later than the force plate (Ps < .05). The accelerometer returned values highly correlated to those from a force plate. Compared with a force plate, a wireless, 3-axis accelerometer is a less expensive and more portable system with which to measure the step-up-and-over test.
John A. Nyland, Dean P. Currier, J. Michael Ray and Mitchell J. Duby
This paper discusses function changes during an accelerated rehabilitation program at 6, 10, and 52 weeks postsurgery for a college athlete following anterior cruciate ligament reconstruction/meniscectomy of the left knee. The effects of combined pulsed electromagnetic field (PEMF) and neuromuscular electrical stimulation (NMES) on knee extensor torque, thigh girth, and pain level are presented. PEMF-NMES decreased stimulation pain by 76%. Knee extensor isometric torque increased by 23%, and thigh girth decreased less than 5% at 6 weeks. Knee extensor isokinetic torque was 13% and 3% deficient at 90°/s and 240°/s, and standing single-leg broad jump distance was 19% deficient at 10 weeks. Knee extensor isokinetic torque was 1% and 1.5% greater at 90°/s and 240°/s, and standing single-leg broad jump distance was 11% deficient at 52 weeks. Knee anterior laxity was 2 mm at 10 weeks and 3 mm at 52 weeks. PEMF-NMES appears to comfortably enhance knee extensor torque gains and diminish thigh girth loss. Despite early return to practice, functional deficit remained and anterior laxity was increased at 52 weeks.
Jay R. Ebert, Anne Smith, Peter K. Edwards and Timothy R. Ackland
Matrix-induced autologous chondrocyte implantation (MACI) is an established technique for the repair of knee chondral defects. Despite the reported clinical improvement in knee pain and symptoms, little is known on the recovery of knee strength and its return to an appropriate level compared with the unaffected limb.
To investigate the progression of isokinetic knee strength and limb symmetry after MACI.
Private functional rehabilitation facility.
58 patients treated with MACI for full-thickness cartilage defects to the femoral condyles.
MACI and a standardized rehabilitation protocol.
Main Outcome Measures:
Preoperatively and at 1, 2, and 5 y postsurgery, patients underwent a 3-repetition-maximum straight-leg raise test, as well as assessment of isokinetic knee-flexor and -extensor torque and hamstring:quadriceps (H:Q) ratios. Correlation analysis investigated the association between strength and pain, demographics, defect, and surgery characteristics. Linear-regression analysis estimated differences in strength measures between the operated and nonoperated limbs, as well as Limb Symmetry Indexes (LSI) over time.
Peak knee-extension torque improved significantly over time for both limbs but was significantly lower on the operated limb preoperatively and at 1, 2, and 5 y. Mean LSIs of 77.0%, 83.0%, and 86.5% were observed at 1, 2, and 5 y, respectively, while 53.4–72.4% of patients demonstrated an LSI ≤ 90% across the postoperative timeline. Peak knee-flexion torque was significantly lower on the operated limb preoperatively and at 1 year. H:Q ratios were significantly higher on the operated limb at all time points.
While peak knee-flexion and hip-flexor strength were within normal limits, the majority of patients in this study still demonstrated an LSI for peak knee-extensor strength ≤ 90%, even at 5 y. It is unknown how this prolonged knee-extensor deficit may affect long-term graft outcome and risk of reinjury after return to activity.
Francesca Genoese, Shelby E. Baez, Nicholas Heebner, Matthew C. Hoch and Johanna M. Hoch
subsequent reconstruction, and can affect self-perceived knee function. 3 – 5 However, limited research has examined the effect of injury-related fear on other disease-oriented, functional, and self-reported outcomes in individuals after ACLR. Increased injury-related fear, 2 , 6 decreased self
Christopher Kuenze, Lisa Cadmus-Bertram, Karin Pfieffer, Stephanie Trigsted, Dane Cook, Caroline Lisee and David Bell
. This is based on the premise that an individual reporting high levels of knee function, low levels of knee pain, and adequate quadriceps strength is well prepared to begin a reintegration of physical activity while minimizing the potential risk of reinjury or secondary musculoskeletal injury. Success
Gemma V. Espí-López, Pilar Serra-Añó, David Cobo-Pascual, Manuel Zarzoso, Luis Suso-Martí, Ferran Cuenca-Martínez and Marta Inglés
literature, and several papers report improvements in these variables through rehabilitation programs, 7 for example, previous research has shown that strength exercise programs are able to improve knee function. In addition, increased knee stability and proprioception have also been observed through the