Functional recovery after anterior cruciate ligament reconstruction: a longitudinal perspective.

OBJECTIVE: To evaluate functional hop performance in subjects with an anterior cruciate ligament (ACL) reconstruction with a bone-patellar tendon-bone graft during 12, 18, 26, 39, and 52 weeks. DESIGN: A longitudinal comparative study. SETTING: University research laboratory. PARTICIPANTS: Patients (N=19) were evaluated at 12, 18, 26, 39, and 52 weeks after ACL reconstruction surgery. INTERVENTION: Testing on 5 separate occasions. MAIN OUTCOME MEASURES: The Cincinnati Knee Rating System and analog scales, the 6-meter timed hop, crossover hop, stair hop, and vertical hop, and limb symmetry indices. RESULTS: The uninjured and injured legs and test order were randomized. There was a significant test occasion main effect for both the Cincinnati and analog scores (P=.001). Subjective rating scores improved over the 5 testing occasions. For all 4 hop tests, test occasion and limb main effects were significant (P=.001). Paired t test comparisons at each testing occasion indicated a significant difference between the reconstructed and uninjured limb (P<.05). Furthermore, significant test occasion main effects were noted for limb symmetry indices for the 4 hop tests (P=.001). Using a score of greater than or equal to 85% as a criterion for normative limb symmetry, normative scores were recorded in the 6-m timed hop at the week 18 test occasion, the stair hop and vertical hop at the week 26 test occasion, and the crossover hop at the week 39 test occasion. CONCLUSIONS: These hop tests showed different levels of imposed demands on the knee that could be used to assess functional recovery and readiness to resume sport.

Effect of ankle taping on angle and force matching and strength of the plantar flexors.

OBJECTIVE: Investigate the effect of ankle taping on plantar-flexion strength, angle matching and force matching. DESIGN: Single group, repeated measures. SETTING: Laboratory of an educational institution. PARTICIPANTS: Twenty uninjured females (22.9 ± 3.6 years). MAIN OUTCOME MEASURES: Tape was applied to the ankle using a conventional hindfoot technique. Angle and force matching, and plantar-flexor strength were assessed using the purpose built dual ankle dynamometer, and measures were taken prior to and following taping. Angle matching was assessed passively and actively at 10, 15 and 20° of plantar-flexion. Participants were required to match the angle of the reference leg with the contralateral leg. Force matching was assessed at 10° of plantar-flexion and participants matched the torque of the reference leg with the contralateral leg. RESULTS: Taping had no effect on absolute errors during active or passive angle matching. Regardless of taping, the ankle angle tested had a significant effect on passive angle matching (p < 0.001); subjects were most accurate at matching a plantar-flexion angle of 20°. Ankle taping had no effect on force matching. Taping significantly improved peak plantar-flexion strength by 20% (p = 0.028). CONCLUSION: Ankle taping has little effect on contralateral force and angle matching, but it can enhance peak plantar-flexion strength.

The effects of vestibular stimulation and fatigue on postural control in classical ballet dancers.

This study aimed to investigate the effects of ballet-specific vestibular stimulation and fatigue on static postural control in ballet dancers and to establish whether these effects differ across varying levels of ballet training. Dancers were divided into three groups: professional, pre-professional, and recreational. Static postural control of 23 dancers was measured on a force platform at baseline and then immediately, 30 seconds, and 60 seconds after vestibular stimulation (pirouettes) and induction of fatigue (repetitive jumps). The professional dancers' balance was unaffected by both the vestibular stimulation and the fatigue task. The pre-professional and recreational dancers' static sway increased following both perturbations. It is concluded that professional dancers are able to compensate for vestibular and fatiguing perturbations due to a higher level of skill-specific motor training.

Functional measurement of knee joint position sense after anterior cruciate ligament reconstruction.

OBJECTIVE: To examine for differences in joint position sense (JPS) between knees with reconstructed anterior cruciate ligaments (ACLs) and uninjured knees by using a functional weight-bearing measurement method. DESIGN: Two-way repeated-measures in a convenience sample. SETTING: An Australian university rehabilitation laboratory. PARTICIPANTS: Nine subjects presenting at 12 to 16 months after unilateral ACL reconstruction using the semitendinosus/gracilis graft who were recruited from 2 orthopedic surgeons. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: JPS of the reconstructed and uninjured knees was examined by using the Peak Motus motion measurement system to record target joint angles and to calculate reproduced angles after limb movement into flexion and extension, performed in a weight-bearing position. RESULTS: There were no significant differences in JPS between reconstructed and uninjured knees (P=.68) or between the flexion and extension tasks (P=.47). CONCLUSION: There was no deficit in knee JPS 12 to 16 months after ACL reconstruction, as measured by a functional weight-bearing method. Further studies should examine the clinical utility of the method as a way to evaluate functional aspects of knee joint proprioception.