Effect of genu recurvatum on the anterior cruciate ligament-deficient knee during gait

Use of the Rehabilitation Treatment Specification System (RTSS) in the management of nitrous oxide (N2O)-induced spinal cord injury

Nitrous oxide (N₂O) is an inhaled anaesthetic gas and a popular intoxicant. Excessive recreational use can cause spinal cord myelopathy. Previous studies have discussed the medical management. However, none have specified the sensorimotor rehabilitation management. This case report documents the investigations, physical rehabilitation and functional outcomes in two cases of N₂O-associated myelopathy. Both presented with lower limb strength and sensorimotor integration impairments resulting in ataxic ambulation. Dorsal column signal abnormality was observed on T2-weighted MRI in one case. Myelopathy was diagnosed based on clinical presentation and both were treated with vitamin B₁₂ Rehabilitation was conceived and specified using the Rehabilitation Treatment Specification System (RTSS). Both cases achieved independent indoor gait on hospital discharge, and full function at 9 months in one case. Appropriate and timely medical management and reasoned rehabilitation provided excellent functional outcomes for N₂O-related myelopathy. By using the RTSS, reasoned rehabilitation efficacy can be tested in the future.

Asymptomatic Genu Recurvatum reshapes lower limb sagittal joint and elevation angles during gait at different speeds

BACKGROUND

Kinematic characteristics of walking with an asymptomatic genu recurvatum are currently unknown. The objective of this study is to characterize the lower limb sagittal joint and elevation angles during walking in participants with asymptomatic genu recurvatum and compare it with control participants without knee deformation at different speeds.

METHODS

The spatio-temporal parameters and kinematics of the lower limb were recorded using an optoelectronic motion capture system in 26 participants (n = 13 with genu recurvatum and n = 13 controls). The participants walked on an instrumented treadmill during five minutes at three different speeds: slow, medium and fast.

RESULTS

Participants with genu recurvatum showed several significant differences with controls: a narrower step width, a greater maximum hip joint extension angle, a greater knee joint extension angle at mid stance, a lower maximum knee joint flexion angle during the swing phase, and a greater ankle joint extension angle at the end of the gait cycle. Participants with genu recurvatum had a greater minimum thigh elevation angle, a greater maximum foot elevation angle, and a change in the orientation of the covariance plane. Walking speed had a significant effect on nearly all lower limb joint and elevation angles, and covariance plane parameters.

CONCLUSION

Our findings show that genu recurvatum reshapes lower limb sagittal joint and elevation angles during walking at different speeds but preserves the covariation of elevation angles along a plane during both stance and swing phases and the rotation of this plane with increasing speed.

The association between genu recurvatum angle and the strength of the hip and knee muscles in standing workers

BACKGROUND

Increased genu recurvatum (GR) angle is a risk factor for knee injury. Identification of factors causing GR is important for the prevention and rehabilitation of GR. Few studies have investigated the association between muscle strength and GR.

OBJECTIVE

To examine the association between GR angle and hip and knee muscle strength in standing workersMETHODS:The participants in this study were 110 healthy volunteers (59 male, 51 female) who performed standing work in a theme park. The GR angle, muscle strength, and strength ratio of the lower extremities were measured to determine their associations with GR. The GR angle was measured using a Smart KEMA motion sensor, and muscle strength was assessed using a Smart KEMA strength sensor. Stepwise multiple regression models were used to investigate which muscles contributed most to the extent of the GR angle.

RESULTS

Stepwise multiple regression analysis showed that the decreased hip external rotator to hip internal rotator ratio, increased knee extensor to knee flexor ratio, and young age were associated with an increased GR angle.

CONCLUSIONS

Many factors are known to increase the GR angle. However, this study investigated the roles of only hip and knee muscle strength. The results suggest that muscle strength ratios are more important than the weakness of any muscle.

Early weight-bearing after anterior cruciate ligament reconstruction with hamstring grafts induce femoral bone tunnel enlargement: a prospective clinical and radiographic study

BACKGROUND

Bone tunnel enlargement following primary anterior cruciate ligament (ACL) reconstruction with soft tissue graft might be a severe disadvantage for revision surgery. The postoperative rehabilitation protocol including the non-weight-bearing periods were different depending on the surgeon or institute. To determine the relationship between femoral bone tunnel enlargement and the postoperative non-weight-bearing period after double-bundle ACL reconstruction with hamstring grafts.

METHODS

Forty-two patients who underwent primary double-bundle ACL reconstruction with hamstring grafts were divided into two postoperative non-weight-bearing protocol groups: 1-week non-weight-bearing postoperatively (group A, n = 19); and 2-week non-weight-bearing (group B, n = 18). Five cases were excluded due to additional knee injury, pregnancy, and lost to follow-up. Bone tunnel enlargement was evaluated by computed digital radiographs (anteroposterior (A-P) and lateral views) taken on the first postoperative day and at 12 months. Each tunnel diameter was shown as a percentage to the maximum joint width of the proximal tibia in the A-P view, or a percentage of the maximum diameter of the patella in the lateral view. To determine the incidence of tunnel enlargement, percentage diameter changes of more than 10% were defined as an enlarged tunnel. The magnitude of tunnel enlargement and the standard clinical evaluation were also evaluated.

RESULTS

There were no significant differences between groups in the incidences of anteromedial and posterolateral bone tunnel enlargement, both in the A-P and lateral views (2 × 2 Chi-squared test). The magnitude of femoral posterolateral bone tunnel enlargement was significantly greater in group A in the A-P view (p = 0.01) and lateral view (p = 0.03) (Mann Whitney U-test). Twelve months after surgery, the Lysholm score and Tegner activity level scale were not significantly different between the groups.

CONCLUSIONS

This prospective, clinical and radiographical study showed that early weight-bearing protocol after double-bundle ACL reconstruction with hamstring grafts might have the potential risk of significant postoperative femoral bone tunnel enlargement of the posterolateral bundle. There was no significant difference in clinical outcomes by postoperative non-weight-bearing period. To reduce and prevent the femoral bone tunnel enlargement, the comprehensive management could be considered and required to establish the suitable early stage rehabilitation protocol after surgery.

TRIAL REGISTRATION

Trial registration number; UMIN000036212 . Scientific title: Prospective comparisons of femoral tunnel enlargement with two different postoperative non weight bearing periods after double-bundle anterior cruciate ligament reconstruction with hamstring grafts. Registered date: 15 Mar 2019 (retrospectively registered).

Three-dimensional knee kinematics in patients with a discoid lateral meniscus during gait

BACKGROUND

To date, the knee kinematics of a discoid lateral meniscus (DLM) has not been elucidated. The aim was to investigate the three-dimensional knee kinematics in knees with a DLM using gait analysis.

METHODS

Ten patients (mean: 14years) diagnosed with bilateral DLM and unilaterally symptomatic snapping as well as 10 healthy controls (mean: 23years) participated in the study. Each patient with a DLM had unilaterally snapping knee in full extension and deep flexion. The three-dimensional gait analysis was performed with the point cluster technique. All subjects were asked to walk on a level floor at the speed of their choice. In the sagittal plane, knee excursion was separately evaluated during the weight acceptance phase and the mid-stance phase. In the axial plane, knee excursion during the stance phase was assessed. Finally, knee excursion during the whole gait cycle was evaluated in the frontal plane. Statistical comparison was conducted between groups, and between both sides in the DLM group.

RESULTS

In the sagittal plane, knee excursions during the weight acceptance phase and the mid-stance phase were significantly smaller in the DLM group than in the control group; in addition, these were smaller on the symptomatic side than on the asymptomatic side in the DLM group. In the axial plane, knee excursion was also significantly smaller on the symptomatic side than on the asymptomatic side in the DLM group, whereas the frontal knee motion did not differ significantly.

CONCLUSION

Less knee motion in the sagittal plane may prevent snapping during extension and flexion in patients with a DLM.

LEVEL OF EVIDENCE

III.

Three-dimensional kinematic and kinetic gait deviations in individuals with chronic anterior cruciate ligament deficient knee: A systematic review and meta-analysis

BACKGROUND

Altered joint motion that occurs in people with an anterior cruciate ligament deficient knee is proposed to play a role in the initiation of knee osteoarthritis, however, the exact mechanism is poorly understood. Although several studies have investigated gait deviations in individuals with chronic anterior cruciate ligament deficient knee in the frontal and transverse planes, no systematic review has summarized the kinematic and kinetic deviations in these two planes.

METHODS

We searched five electronic databases from inception to 14th October 2013, with key words related to anterior cruciate ligament, biomechanics and gait, and limited to human studies only. Two independent reviewers assessed eligibility based on predetermined inclusion/exclusion criteria and methodological quality was evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology statement checklist.

FINDINGS

We identified 16 studies, totaling 183 subjects with anterior cruciate ligament deficient knee and 211 healthy subjects. Due to the variability in reported outcomes, we could only perform meta-analysis for 13 sagittal plane outcomes. The only significant finding from our meta-analysis showed that individuals with anterior cruciate ligament deficient knee demonstrated a significantly greater external hip flexor angular impulse compared to control (P=0.03).

INTERPRETATION

No consensus about what constitutes a typical walking pattern in individuals with anterior cruciate ligament deficient knee can be made, nor can conclusions be derived to explain if gait deviations in the frontal and transverse plane contributed to the development of the knee osteoarthritis among this population.

Gait changes of the ACL-deficient knee 3D kinematic assessment

PURPOSE

Static, one-dimensional testing cannot predict the behaviour of the anterior cruciate ligament (ACL)-deficient knee under realistic loading conditions. Currently, the most widely accepted method for assessing joint movement patterns is gait analysis. The purpose of the study was in vivo evaluation of the behaviour of the anterior cruciate ligament-deficient (ACLD) knees during walking, using 3D, real-time assessment tool.

METHODS

Biomechanical data were collected prospectively on 30 patients with ACL rupture and 15 healthy subjects as a control group, with KneeKg™ System. Kinematic data were recorded in vivo during treadmill walking at self-selected speed. Flexion/extension, abduction/adduction, anterior/posterior tibial translation and external/internal tibial rotation were compared between groups.

RESULTS

The ACLD patients showed a significant lower extension of the knee joint during stance phase (p < 0.05; 13.2° ± 2.1° and 7.3° ± 2.7°, for ACLD and control group, respectively). A significant difference in tibial rotation angle was found in ACLD knees compared to control knees (p < 0.05). The patients with ACLD rotated the tibia more internally (-1.4° ± 0.2°) during the mid-stance phase, than control group (0.2° ± 0.3°). There was no significant difference in anteroposterior translation and adduction-abduction angles.

CONCLUSION

Significant alterations of joint kinematics in the ACLD knee were revealed in this study by manifesting a higher flexion gait strategy and excessive internal tibial rotation during walking that could result in a more rapid cartilage thinning throughout the knee. The preoperative data obtained in this study will be useful to understand the post-ACL reconstruction kinematic behaviour of the knee.

CLINICAL RELEVANCE

The findings in this study indicate that ACLD knee may adapt functionally to prevent excessive anterior-posterior translation but they fail to avoid rotational instability.

Effect of unstable meniscal injury on three-dimensional knee kinematics during gait in anterior cruciate ligament-deficient patients

BACKGROUND

Our purpose was to clarify the differences of three-dimensional knee kinematics in anterior cruciate ligament (ACL)-deficient patients between with and without meniscal injury using gait analysis.

METHODS

A total of 72 knees in 36 young athletes with primary and unilateral ACL injury, with a mean age of 22 years, participated. Gait analysis was done before surgery. According to the arthroscopic findings, patients were divided into two groups. The patients with an unstable meniscal tear were allocated to the meniscal injury group (ACL+M group), and the patients without a meniscal tear were allocated to the no meniscal injury group (ACL group). In the gait analysis, three-dimensional knee kinematics was evaluated and compared.

RESULTS

The patients in both groups exhibited lower sagittal plane knee excursions and peak knee extension angles on the affected limb than on the unaffected limb during the mid-stance. In terms of the axial plane, a rotation angle was significantly smaller in the affected knees than in the unaffected knees in the ACL group. On the other hand, an opposite phenomenon was observed in the ACL+M group. Moreover, a significantly larger rotation angle in the affected knees during the stance phase and the whole gait cycle was observed in the ACL+M group than in the ACL group.

CONCLUSION

Increased rotational motion during the gait was observed in the ACL-deficient knees combined with unstable meniscal injuries. Meniscal condition may be a key factor for compensatory gait mechanics to prevent rotatory instability in ACL-deficient patients patients.

LEVEL OF EVIDENCE

III.

Prospective comparisons of femoral tunnel enlargement with 3 different postoperative immobilization periods after double-bundle anterior cruciate ligament reconstruction with hamstring grafts

PURPOSE

To determine the effect of differing postoperative immobilization periods on femoral bone tunnel enlargement and clinical outcome after double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring grafts.

METHODS

Fifty-one patients undergoing primary double-bundle ACL reconstruction with hamstring grafts were divided into 3 postoperative immobilization protocol groups: 2-day immobilization with the knee in 20° of flexion postoperatively (group A, n = 18); 1-week immobilization (group B, n = 17); and 2-week immobilization (group C, n = 16). Bone tunnel enlargement was determined by computed digital radiographs taken on the first postoperative day and at 24 months in the anteroposterior (AP) and lateral views. Each tunnel diameter was shown as a percentage of the maximum joint width of the proximal tibia on the AP view or a percentage of the maximum diameter of the patella on the lateral view. To determine the incidence of tunnel enlargement, a percentage diameter change of more than 10% was defined as an enlarged tunnel. The standard clinical evaluation was also performed. This study used nonrandomized procedures.

RESULTS

In each group there were no significant differences in the incidence and magnitude of anteromedial and posterolateral bone tunnel enlargement on both the AP and lateral views (1-factor analysis of variance). Group C showed significantly less muscle strength in knee extension compared with the contralateral knee (85.3% ± 18.4%) than group A (93.7% ± 13.1%, P = .049) and group B (96.8% ± 12.9%, P = .044).

CONCLUSIONS

This prospective radiographic study showed that femoral bone tunnel enlargement, in both the anteromedial and posterolateral tunnels, may occur after double-bundle ACL reconstruction with hamstring grafts despite different postoperative immobilization periods, with no significant difference in the incidence and magnitude among groups with differing postoperative immobilization periods. In addition, a 2-week immobilization period after surgery showed harmful effects, such as significantly less quadriceps muscle strength.

LEVEL OF EVIDENCE

Level II, prospective comparative study.