Timing Of Peak Knee Flexion Research Articles

Local Anesthesia of the Sole of the Foot Alters Lower Limb Kinematics and Kinetics During Running

1649 PURPOSE: The purpose of this study was to investigate whether local anesthesia of the sole of the foot would alter lower limb kinematics, kinetics and perceptions of comfort during running. METHODS: The study was conducted as a randomised double blind placebo controlled crossover clinical trial (n = 10). Either a topical anaesthetic cream (EMLA™, lignocaine and prilocaine 25 mg/g) or placebo (CON) was applied after which subjects rested in sitting for 60 minutes and then performed 10 running trials in the Motion Analysis Laboratory to determine their kinetics and lower limb kinematics during running. Thereafter, they were required to run 840 metres on an indoor tartan track and rate their perceived comfort (Scale 0–10) during the run. RESULTS: The step length (m) (EMLA: 0.68 ± 0.065, CON: 0.718 ± 0.081: p = 0.0036) and stride length (m) (EMLA: 1.375 ± 0.146, CON: 1.43 ± 0.18: p = 0.026) in the laboratory and mean velocity (m/sec) (EMLA: 3.87 ± 0.358, CON: 4.07 ± 0.317: p = 0.0036) on the indoor track decreased significantly following EMLA™. Peak horizontal propulsive force (BW) was significantly reduced during the EMLA trial compared with the CON trial (EMLA: 0.162 ± 0.044 BW, CON: 0.177 ± 0.049 BW: p = 0.043). There was a significant increase (p = 0.0053) in dorsiflexion of the ankle at heelstrike (Ahs) during the EMLA trial (degrees) (EMLA: −3.23 ± 4.19, CON: 0.233 ± 4.9) compared with CON. There was also a significant increase of dorsiflexion of the ankle at the time of peak knee extension (Asw) (degrees) (EMLA: −4.113 ± 4.55, CON: −1.59 ± 4.55: p = 0.0078) and at the time of peak knee flexion in the stance phase (Ast) (degrees) (EMLA: −9.69 ± 5.43, CON: −7.2 ± 6.3: p = 0.028) during the EMLA trial compared with CON. CONCLUSION: The application of a topical local anesthetic cream to the sole of the foot reduced self-selected running speed and altered selected kinetic and kinematic variables during running. Sensory input from cutaneous afferents in the foot alters gait mainly by changing running speed.

Local Anesthesia of the Sole of the Foot Alters Lower Limb Kinematics and Kinetics During Running

1649 PURPOSE: The purpose of this study was to investigate whether local anesthesia of the sole of the foot would alter lower limb kinematics, kinetics and perceptions of comfort during running. METHODS: The study was conducted as a randomised double blind placebo controlled crossover clinical trial (n = 10). Either a topical anaesthetic cream (EMLA™, lignocaine and prilocaine 25 mg/g) or placebo (CON) was applied after which subjects rested in sitting for 60 minutes and then performed 10 running trials in the Motion Analysis Laboratory to determine their kinetics and lower limb kinematics during running. Thereafter, they were required to run 840 metres on an indoor tartan track and rate their perceived comfort (Scale 0–10) during the run. RESULTS: The step length (m) (EMLA: 0.68 ± 0.065, CON: 0.718 ± 0.081: p = 0.0036) and stride length (m) (EMLA: 1.375 ± 0.146, CON: 1.43 ± 0.18: p = 0.026) in the laboratory and mean velocity (m/sec) (EMLA: 3.87 ± 0.358, CON: 4.07 ± 0.317: p = 0.0036) on the indoor track decreased significantly following EMLA™. Peak horizontal propulsive force (BW) was significantly reduced during the EMLA trial compared with the CON trial (EMLA: 0.162 ± 0.044 BW, CON: 0.177 ± 0.049 BW: p = 0.043). There was a significant increase (p = 0.0053) in dorsiflexion of the ankle at heelstrike (Ahs) during the EMLA trial (degrees) (EMLA: −3.23 ± 4.19, CON: 0.233 ± 4.9) compared with CON. There was also a significant increase of dorsiflexion of the ankle at the time of peak knee extension (Asw) (degrees) (EMLA: −4.113 ± 4.55, CON: −1.59 ± 4.55: p = 0.0078) and at the time of peak knee flexion in the stance phase (Ast) (degrees) (EMLA: −9.69 ± 5.43, CON: −7.2 ± 6.3: p = 0.028) during the EMLA trial compared with CON. CONCLUSION: The application of a topical local anesthetic cream to the sole of the foot reduced self-selected running speed and altered selected kinetic and kinematic variables during running. Sensory input from cutaneous afferents in the foot alters gait mainly by changing running speed.

Predictive Value of the Duncan-Ely Test in Distal Rectus Femoris Transfer

Fifty-six patients who underwent 94 distal rectus femoris transfers and pre- and postoperative gait analyses were retrospectively reviewed. The patients were divided into three groups based on pre- and postoperative Duncan-Ely tests. Group A (34 limbs) had positive tests both before and after surgery. Group B (46 limbs) had positive tests before surgery and negative tests after surgery. Group C (13 limbs) had negative tests both before and after surgery. One limb had a negative test before surgery and a positive test after surgery and was not included in any group. Knee arc increased significantly in both groups with positive preoperative Duncan-Ely tests (groups A and B), but not in the group with negative preoperative tests (group C). The timing of peak knee flexion in swing improved in all groups, but the change was smaller and not statistically significant in the group with negative preoperative tests (group C). The findings of the current study indicate that the Duncan-Ely test may be a helpful predictor of outcome in children for whom distal rectus femoris transfer is being considered. Caution should be exercised when patients have weak quadriceps and a negative Duncan-Ely test before surgery, particularly when concurrent calf lengthening procedures are planned.

Predictive value of the Duncan-Ely test in distal rectus femoris transfer.

Fifty-six patients who underwent 94 distal rectus femoris transfers and pre- and postoperative gait analyses were retrospectively reviewed. The patients were divided into three groups based on pre- and postoperative Duncan-Ely tests. Group A (34 limbs) had positive tests both before and after surgery. Group B (46 limbs) had positive tests before surgery and negative tests after surgery. Group C (13 limbs) had negative tests both before and after surgery. One limb had a negative test before surgery and a positive test after surgery and was not included in any group. Knee arc increased significantly in both groups with positive preoperative Duncan-Ely tests (groups A and B), but not in the group with negative preoperative tests (group C). The timing of peak knee flexion in swing improved in all groups, but the change was smaller and not statistically significant in the group with negative preoperative tests (group C). The findings of the current study indicate that the Duncan-Ely test may be a helpful predictor of outcome in children for whom distal rectus femoris transfer is being considered. Caution should be exercised when patients have weak quadriceps and a negative Duncan-Ely test before surgery, particularly when concurrent calf lengthening procedures are planned.

Clinical utility of the Duncan‐Ely test for rectus femoris dysfunction during the swing phase of gait

The Ely Test (or Duncan‐Ely test) has been accepted as a clinical tool to assess rectus femoris spasticity by passively flexing the knee rapidly while the patient lies prone in a relaxed state. In this retrospective review, patients’dynamic knee range of motion (ROM) during gait and an electromyogram (EMG) were compared with the results of the Ely test. Data for 70 patients (44 males, 26 females; 104 limbs) were included. Mean age of patients was 13 years, SD 9 years, range 4 years 5 months to 54 years. All patients were diagnosed with cerebral palsy (spastic diplegia, n=42; spastic quadriplegia, n=15, and hemiplegia, n=13). All patients were ambulatory (50 independent, 20 with assistive devices). A standard matrix was used to calculate sensitivity and specificity of the Ely test as well as its positive and negative predictive value. For the gait variables examined (decreased dynamic knee ROM, timing of peak knee flexion, and abnormal EMG in swing) the sensitivity of the Ely test ranged from 56 to 59% and the specificity ranged from 64 to 85%. For the same variables the positive predictive value ranged from 91 to 98% and the negative predictive value ranged from 4 to 19%. The Ely test was shown to have a good positive predictive value (i.e. the certainty about the presence of rectus spasticity in patients with a positive Ely test result) for rectus femoris dysfunction during gait.

Clinical utility of the Duncan-Ely test for rectus femoris dysfunction during the swing phase of gait.

The Ely Test (or Duncan-Ely test) has been accepted as a clinical tool to assess rectus femoris spasticity by passively flexing the knee rapidly while the patient lies prone in a relaxed state. In this retrospective review, patients' dynamic knee range of motion (ROM) during gait and an electromyogram (EMG) were compared with the results of the Ely test. Data for 70 patients (44 males, 26 females; 104 limbs) were included. Mean age of patients was 13 years, SD 9 years, range 4 years 5 months to 54 years. All patients were diagnosed with cerebral palsy (spastic diplegia, n = 42; spastic quadriplegia, n = 15, and hemiplegia, n = 13). All patients were ambulatory (50 independent, 20 with assistive devices). A standard matrix was used to calculate sensitivity and specificity of the Ely test as well as its positive and negative predictive value. For the gait variables examined (decreased dynamic knee ROM, timing of peak knee flexion, and abnormal EMG in swing) the sensitivity of the Ely test ranged from 56 to 59% and the specificity ranged from 64 to 85%. For the same variables the positive predictive value ranged from 91 to 98% and the negative predictive value ranged from 4 to 19%. The Ely test was shown to have a good positive predictive value (i.e. the certainty about the presence of rectus spasticity in patients with a positive Ely test result) for rectus femoris dysfunction during gait.

Outcome of Hamstring Lengthening and Distal Rectus Femoris Transfer Surgery

To evaluate the outcome of hamstring lengthening and distal rectus femoris transfer, a retrospective study was performed comparing preoperative and postoperative gait analysis data from 16 children with neurologic involvement. Postoperatively, the timing of peak knee flexion during swing and the total arc of knee motion significantly improved. Hamstring range of motion and knee extension at terminal swing significantly improved, but stride length and gait velocity did not for the overall population. Patients who used braces postoperatively showed an improvement in stride length and velocity when wearing orthoses. This suggests that postoperative bracing may be needed in some patients to maximize the surgical outcome.

Gait Pattern in Patients With Spastic Diplegic Cerebral Palsy Who Underwent Staged Operations

Fifteen patients with spastic diplegic cerebral palsy (CP) were monitored for a mean length of 9.5 years after they underwent staged operations and were evaluated by gait analysis, including joint motion in the sagittal plane and the ground reaction force (GRF) in three dimensions. Results showed an increased hip flexion (132%) at midstance, a reduction of peak knee flexion (PKF) during swing (45%) accompanied by an augmented time of PKF during swing (50%), and an increased dorsiflexion of the ankle during swing (293%) as well as its time during the gait cycle, in comparison with normal values. Moreover, significant decreases of the vertical GRF at the terminal stance and the forward and backward GRF were present. Additionally, it was found that a bilateral popliteal angle < 20 degrees is acceptable in spastic CP. Staged operations gave unpredictable results in the correction of contracture of the hamstrings, the Achilles tendon, and the iliopsoas. The authors are convinced that gait analysis is useful in evaluating these patients and enhances the results of operative treatment, and they have since changed their approach toward multilevel simultaneous corrections.

Prosthetic weight acceptance mechanics in transtibial amputees wearing the Single Axis, Seattle Lite, and Flex Foot.

Loading response challenges the limb with the dual demands of accepting rapidly moving body weight to both absorb the shock of floor contact and create a stable limb over which the body can advance. Delay in achieving foot flat contact with the floor causes a prolonged period of heel only support and results in an unstable base of support for those persons with transtibial amputations. The purpose of this study was to identify mechanical causes of instability during weight acceptance with three different prosthetic foot designs, Single Axis, Seattle Lightfoot, and Flex Foot. Ten male individuals with transtibial amputations were tested on three separate occasions wearing each prosthetic foot. A comparison group of ten individuals without transtibial amputations was also examined. Mean free walking speed was significantly slower for those with transtibial amputations regardless of the prosthetic foot worn (p < 0.05). Contralateral toe off times were significantly later for each prosthetic foot (p < 0.01). The timing of peak knee flexion was found to be significantly later than normal for each prosthetic foot (p < 0.01). To minimize the impact of initial floor contact, persons with an intact limb used rapid plantar flexion, followed by a slower lowering of the foot to the floor. Dorsiflexion then stimulated knee flexion and foot flat. Two altered functions were found for all three prosthetic feet, reduced knee flexion and prolonged heel only support. Diminished knee flexion reflected delayed dorsiflexion and tibial advancement as a result of the cushioned heel. Lateness in reaching foot flat was also found. To improve the walking abilities of those persons with transtibial amputations, prosthetic foot designs need to incorporate mechanisms which promote early foot flat while preserving limb stability.

General gait patterns in spastic diplegia

Stiff-knee gait (SKG) is commonly encountered in clinic; many other gait abnormalities are seen together with this pathology. Simulation studies revealed that diminished knee flexion (KF) velocity and increased knee extension moments are strongly related with SKG. This study aimed to determine whether tiptoe walking and hip-knee flexion velocity reduction causes SKG pattern in healthy participants.Fourteen able-bodied adults’ (Av. age: 23.0 ± 2.4) heel–toe (N), tiptoe (T), and walking with 5% body weight on both shanks (W) were analyzed using 3D gait analysis by controlling cadence (90 step/min). Repeated measures analysis of variance was used followed by Bonferroni correction (p < 0.05).Walking velocity and cadence were similar for all conditions (p > 0.1). Maximum hip flexion velocity was reduced (15%) significantly as well as the KF velocity (10%) in the W condition. The peak knee flexion (PKF) (8.3% for T, 8.6% for W) and total knee range (10.9% for T, 13% for W) were reduced for both conditions (p < 0.05). The knee range in early swing and the duration between toe-off and PKF were reduced only in the weighted-leg condition (p < 0.05).Slow hip and knee flexion diminished all SKG parameters except timing of PKF. Tiptoe gait itself generated a borderline SKG pattern by reducing the PKF and total knee range. By considering that tiptoe gait and SKG commonly seen together, some of the SKG contributors can be treated by normalizing the ankle motion in the stance and increasing the hip–knee flexion velocity by rigorously planned muscle lengthening procedures and effective strengthening exercises.