Greater fear of re-injury and increased tibial translation in patients who later sustain an ACL graft rupture or a contralateral ACL rupture: a pilot study.

The aim was to compare fear of re-injury, patient reported function, static and dynamic tibial translation and muscle strength assessed before and 5 weeks after an anterior cruciate ligament (ACL) reconstruction between individuals who sustained a subsequent ACL graft rupture or a contralateral ACL injury within 5 years after the reconstruction, and individuals with no subsequent injury. Nineteen patients were investigated before, and 5 weeks after an ACL reconstruction with a quadruple hamstring tendon graft. At 5 years follow up, 3 patients had sustained an ACL graft rupture and 2 patients had sustained a contralateral ACL rupture. Fear of re-injury, confidence with the knee, patient reported function, activity level, static and dynamic tibial translation and muscle strength were assessed. The re-injured group reported greater fear of re-injury and had greater static tibial translation in both knees before the ACL reconstruction compared to those who did not sustain another ACL injury. There were no other differences between groups. In conclusion, fear of re-injury and static tibial translation before the index ACL reconstruction were greater in patients who later on suffered an ACL graft rupture or a contralateral ACL rupture. These factors may predict a subsequent ACL injury.

Static and dynamic tibial translation before, 5 weeks after, and 5 years after anterior cruciate ligament reconstruction.

PURPOSE: To evaluate static and dynamic tibial translation before, 5 weeks after, and 5 years after anterior cruciate ligament (ACL) reconstruction. To explore whether static and dynamic tibial translation are correlated. METHODS: Ten patients undergoing quadruple hamstring tendon graft ACL reconstruction were evaluated before, 5 weeks after, and 5 years after ACL reconstruction. Sagittal tibial translation was measured during the Lachman test (static translation) and during gait (dynamic translation) using a CA-4000 electrogoniometer. RESULTS: Five years after ACL reconstruction, static tibial translation did not differ between knees (Lachman test 90 N and 134 N n.s.). In contrast, there was greater maximal anterior tibial translation during gait in ACL-reconstructed knees than in uninjured knees (5.5 ± 1.4 vs. 4.5 ± 1.6 mm, P = 0.028). There were no differences in static or dynamic tibial translation between the 5-year follow-up and before ACL reconstruction or between the 5-year follow-up and the 5-week follow-up. There were no correlations between static and dynamic tibial translation. CONCLUSION: Although static tibial translation did not differ between knees 5 years after ACL reconstruction, dynamic tibial translation during gait was greater in ACL-reconstructed knees than in uninjured knees. Neither static nor dynamic tibial translation changed 5 years after ACL reconstruction as compared to before surgery and 5 weeks after surgery. Static tibial translation did not correlate with dynamic tibial translation. CLINICAL RELEVANCE: This study indicates that although the knee is stable during static measurements, kinematics during gait is impaired 5 years after ACL reconstruction. This may affect the return to sport and risk of osteoarthritis. LEVEL OF EVIDENCE: Case series, Level IV.

The impact of psychological readiness to return to sport and recreational activities after anterior cruciate ligament reconstruction.

BACKGROUND: This cross-sectional study aimed to examine whether appraisal of knee function, psychological and demographic factors were related to returning to the preinjury sport and recreational activity following anterior cruciate ligament (ACL) reconstruction. METHOD: 164 participants completed a questionnaire battery at 1-7 years after primary ACL reconstruction. The battery included questionnaires evaluating knee self-efficacy, health locus of control, psychological readiness to return to sport and recreational activity, and fear of reinjury; and self-reported knee function in sport-specific tasks, knee-related quality of life and satisfaction with knee function. The primary outcome was returning to the preinjury sport or recreational activity. RESULTS: At follow-up, 40% (66/164) had returned to their preinjury activity. Those who returned had more positive psychological responses, reported better knee function in sport and recreational activities, perceived a higher knee-related quality of life and were more satisfied with their current knee function. The main reasons for not returning were not trusting the knee (28%), fear of a new injury (24%) and poor knee function (22%). Psychological readiness to return to sport and recreational activity, measured with the ACL-Return to Sport after Injury scale (was most strongly associated with returning to the preinjury activity). Age, sex and preinjury activity level were not related. CONCLUSIONS: Less than 50% returned to their preinjury sport or recreational activity after ACL reconstruction. Psychological readiness to return to sport and recreation was the factor most strongly associated with returning to the preinjury activity. Including interventions aimed at improving this in postoperative rehabilitation programmes could be warranted to improve the rate of return to sport and recreational activities.

Changes in knee motion pattern after anterior cruciate ligament injury - case report.

BACKGROUND: After an anterior cruciate ligament injury, the contra-lateral non-injured leg has been found to adapt towards the injured leg. Accordingly, in order to study changes in knee motion pattern after an anterior cruciate ligament injury, the ideal is to compare the same leg prior to and after the injury. However, this is very seldom possible. The purpose of the present study was to describe changes in static and dynamic sagittal tibial translation, electromyographic activity and muscle torque relevant to an anterior cruciate ligament tear in one patient evaluated both before and after the injury. METHODS: A male soccer player was examined 11 weeks before and eight weeks after an anterior cruciate ligament injury. Sagittal tibial translation was measured with the CA-4000 electrogoniometer; statically during Lachman's test, and dynamically during isokinetic muscle testing, one-legged squat and level walking. The electromyographic activity of mm. quadriceps and hamstrings, was registered simultaneously during the one-legged squat test. FINDINGS: Static tibial translation was increased by approximately 2 mm, while dynamic tibial translation was decreased by 0.4 mm at isokinetic testing, 0.9 mm at one-legged squat and 2.4 mm during level walking compared to before the injury. Muscle torque decreased 30% and 35% for the quadriceps and the hamstrings muscle, respectively. The electromyographic activity revealed similar activation levels in quadriceps and a doubled level of activation in hamstring compared to before the injury. INTERPRETATION: In spite of an increase in static tibial translation eight weeks after an anterior cruciate ligament injury, the tibial translation decreased during activity, thus indicating that the patient could stiffen the knee in order to protect it against increased shear forces.

Differences in knee joint stabilization between children and adults and between the sexes.

BACKGROUND: Differences in knee joint stabilization between children and adults and between the sexes are not fully understood. PURPOSE: To compare the knee laxity and the dynamic tibial translation between (1) children and adults, (2) girls and boys, and (3) women and men. STUDY DESIGN: Controlled laboratory study. METHODS: Sixty-seven children (aged 8-13 years) and 63 adults (aged 18-30 years) without previous knee injuries participated. Sagittal tibial translation was measured during the instrumented Lachman test at 90 N and 134 N (knee laxity) and during gait (dynamic translation). Tibial translation was recorded with an electrogoniometer. RESULTS: Knee laxity was greater in children than in adults (Lachman test at 90 N: 9.1 ± 2.9 vs 7.3 ± 2.7, respectively; P < .001). In contrast, dynamic tibial translation during gait did not differ between children and adults. Girls and boys did not differ in knee laxity or maximum anterior tibial translation during gait, and men and women did not differ in knee laxity. Women had greater dynamic tibial translation during gait than men (7.8 ± 2.7 vs 5.7 ± 3.0, respectively; P = .004). CONCLUSION: Children had greater knee laxity than adults, whereas the dynamic tibial translation did not differ. In adults, knee laxity did not differ between the sexes, but dynamic tibial translation was greater in women. CLINICAL RELEVANCE: Children and men had less dynamic tibial translation during gait in proportion to their maximum knee laxity. The observed less dynamic tibial translation in children and adult men might be related to their reduced risk of sustaining an anterior cruciate ligament injury.

A comprehensive rehabilitation program with quadriceps strengthening in closed versus open kinetic chain exercise in patients with anterior cruciate ligament deficiency: a randomized clinical trial evaluating dynamic tibial translation and muscle function.

BACKGROUND: There is no consensus regarding the optimal rehabilitation regimen for increasing quadriceps strength after anterior cruciate ligament (ACL) injury. HYPOTHESIS: A comprehensive rehabilitation program supplemented with quadriceps strengthening in open kinetic chain (OKC) exercise will increase quadriceps strength and improve knee function without increasing static or dynamic sagittal tibial translation, compared with the same comprehensive rehabilitation program supplemented with quadriceps strengthening in closed kinetic chain (CKC) exercise, in patients with acute ACL deficiency. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Forty-two patients were tested a mean of 43 days (range, 20-96 days) after an ACL injury. Patients were randomized to rehabilitation with CKC quadriceps strengthening (11 men and 9 women) or OKC quadriceps strengthening (13 men and 9 women). Aside from these quadriceps exercises, the 2 rehabilitation programs were identical. Patients were assessed after 4 months of rehabilitation. Sagittal static translation and dynamic tibial translation were evaluated with a CA-4000 electrogoniometer. Muscle strength, jump performance, and muscle activation were also assessed. Functional outcome was evaluated by determining the Lysholm score and the Knee Injury and Osteoarthritis Outcome Score. RESULTS: There were no group differences in static or dynamic translation after rehabilitation. The OKC group had significantly greater isokinetic quadriceps strength after rehabilitation (P = .009). The hamstring strength, performance on the 1-repetition-maximum squat test, muscle activation, jump performance, and functional outcome did not differ between groups. CONCLUSIONS: Rehabilitation with OKC quadriceps exercise led to significantly greater quadriceps strength compared with rehabilitation with CKC quadriceps exercise. Hamstring strength, static and dynamic translation, and functional outcome were similar between groups. Patients with ACL deficiency may need OKC quadriceps strengthening to regain good muscle torque.

Intra- and interrater reliability of the establishment of one repetition maximum on squat and seated knee extension.

The purpose of the present study was to develop a systematic procedure for the establishment of 1 repetition maximum (1RM) in order to describe an easily accessible test procedure that is applicable for physical therapists and athletic trainers who manage strength training for healthy individuals and patients. Another purpose was to investigate the intra- and interrater reliability of 1RM of squat on 1 leg and seated knee extension on 1 leg. Estimates of leg strength and ratings of perceived exertion formed the basis of the amount of load selected. The reliability of the procedure was assessed by a test-retest design. One RM was established for 16 and 27 healthy individuals, for squat and knee extension, respectively. The intrarater reliability of 1RM of squat on 1 leg was questionable (intraclass correlation [ICC] 0.64, measurement error 13.1 kg). The interrater reliability of 1RM of squat on 1 leg was clinically acceptable (ICC 0.94, measurement error 5.2 kg). The intrarater and interrater reliability of 1RM of seated knee extension on 1 leg was clinically acceptable (ICC 0.90, measurement error 5.1 kg and ICC 0.96, measurement error 3.2 kg, respectively). In conclusion, both exercises can be used to determine the load in exercise programs. In addition, seated knee extension may be used to evaluate strength. In contrast, squat on 1 leg is more uncertain to use at assessments between different days, which may be due to the complexity of this exercise. The test, performed in the described manner, is suitable for physical therapists, athletic trainers, and strength and conditioning coaches in clinical practice working with strength training and rehabilitation.

Passive and dynamic translation in the knee is not influenced by knee exercises in healthy individuals.

No evidence exists that repeated isolated quadriceps contractions lead to increased sagittal plane tibial translation. The purpose was to analyze passive and dynamic tibial translation before, during and after a specific exercise session, including cycling and a maximum number of knee extensions and heel-raises, in healthy individuals. Passive and dynamic sagittal tibial translation was measured on 18 healthy individuals (nine men and nine women) before, during and after a specific exercise session with heavy load, including cycling and maximum number of knee extensions and heel-raises. Sagittal tibial translation during the Lachman test, maximal isometric quadriceps contraction, one-legged squat and gait was registered with the CA-4000 electrogoniometer. The electromyographic (EMG) activity of m. vastus medialis and lateralis, m. gastrocnemius and mm. hamstrings was registered. There was no difference in passive or dynamic sagittal tibial translation during or after the exercise session. No difference could be detected in EMG activity during squat after compared with before the exercise session. In conclusion, the knee exercises did not influence the amount of translation in healthy individuals. The findings indicate that isolated strength training of quadriceps may be included in anterior cruciate ligament rehabilitation programs, even if further specific studies on injured individuals most be performed.