Assessment of the distribution of load on the lower limbs and balance before and after ankle arthrodesis with the Ilizarov method

Developments in circular external fixators: A review

Circular external fixators (CEFs) are successfully used in orthopedics owing to their highly favorable stiffness characteristics which promote distraction osteogenesis. Although there are different designs of external fixators, how these features produce optimal biomechanics through structural and component designs is not well known. Therefore, the aim of this study was to conduct a review on CEFs following the PRISMA statement. A search for relevant research articles was performed on Scopus and PubMed databases providing the related keywords. Furthermore, a patent search was conducted on the Google Patent database. 126 records were found to be eligible for the review. Different designs of CEFs were summarized and tabulated based on their specific features. A bibliometric analysis was also performed on the eligible research papers. Based on the findings, the developments of CEFs in terms of materials, automation, adjustment methods, component designs, wire-clamping, and performance evaluation have been extensively discussed. The trends of the CEF design and future directions are also discussed in this review. Significant research gaps include a lack of consideration towards ease of assembly, effective wire-clamping methods, and CEFs embedded with online patient-monitoring systems, among others. An apparent lack of research interest from low-middle and low-income countries was also identified.

Kinematic parameters after tibial nonunion treatment using the Ilizarov method

Background

Analysis of the outcomes of Ilizarov treatment of tibial nonunion shows functional deficits in the lower limbs of some patients. Biomechanical gait parameters are an important measure for assessing musculoskeletal disorder treatments that aim to restore normal gait. The purpose of our study was to compare the kinematic parameters in patients with tibial nonunion treated using the Ilizarov method and those in a control group of healthy volunteers.

Methods

The study population consisted of 23 patients (age 54.9 ± 16.4 years) who were treated for tibial nonunion using the Ilizarov method, as well as 22 healthy adult controls (age 52.7 ± 10.6 years). Kinematic parameters were measured using a Noraxon MyoMOTION System. We measured hip flexion and abduction, knee flexion, ankle dorsiflexion, inversion, and abduction during walking.

Results

Our analysis showed significant differences between the patients’ operated limbs (OLs) and the controls’ nondominant limbs (NDLs) in the ranges of hip flexion, hip abduction, and knee flexion. We observed no significant differences in knee flexion between the OL and the NOL in patients or between the dominant limb (DL) and NDL in controls. Our evaluation of the kinematic parameters of the ankle joint demonstrated significant differences between the patients’ OLs and the controls’ NDLs in the ranges of ankle dorsiflexion, ankle inversion, and ankle abduction. There were also significant differences in the range of ankle dorsiflexion and ankle abduction between the patients’ NOLs and the controls’ DLs.

Conclusion

Tibial nonunion treatment using the Ilizarov method does not ensure complete normalization of kinematic parameters assessed 24–48 months following the completion of treatment and rehabilitation.

Impairments and Compensations of Static Balance and Plantar Load Distribution in Patients With Chronic Stroke: An Observational Study

OBJECTIVES

The purpose of this study was to explore impairment and compensation characteristics of static balance and plantar load distribution in patients with chronic stroke.

METHODS

We recruited 68 patients who had chronic stroke who could stand independently (stroke group) and 30 healthy individuals (control group) with the Zebris FDM platform. Static balance parameters, including center of pressure (COP) ellipse sway area, COP path length, and angle-θ between y and major axis, were compared between 2 groups under standard standing posture. In the stroke group, balance parameters were re-tested under their preferring standing posture. Plantar load distribution was also assessed. Another 8 patients with chronic stroke who could not stand independently and had to rely on a crutch were enrolled to analyze the characteristics of balance compensation.

RESULTS

In the stroke group, the ellipse sway area, COP path length, and angle-θ were significantly larger than those of the control group. Sixty-one (89.7%) patients preferred standing with the affected foot outward-forward supporting, and their preferring standing balance was better than that of standard standing. All patients who could not stand independently tended to compensate for balance with a crutch supporting laterally and also preferred standing with a typical posture- the affected foot was outward-forward.

CONCLUSIONS

In patients post stroke, static balance is impaired mainly at the lateral direction, and patients commonly locate the crutch laterally for compensation of lateral balance. Patients preferred standing with the affected foot outward-forward supporting, and their preferring standing balance was better than that of standard standing, which challenged the necessity of training standing symmetrically.

Kinematic Parameters Following Pilon Fracture Treatment with the Ilizarov Method

Background: The purpose of our study was to analyze kinematic parameters following pilon fracture treatment with the Ilizarov method. Methods: Our study assessed kinematic parameters of gait in 23 patients with pilon fractures treated with the Ilizarov method. Patients had completed their treatment 24−48 months prior to measurements. The range-of-motion values in the non-operated limb (NOL) and operated limb (OL) were compared. Kinematic parameters were measured using the Noraxon MyoMOTION System. Results: We observed no significant differences in hip flexion, hip abduction, or knee flection between the OLs and NOLs in patients after treatment with the Ilizarov method. We observed significant differences in the ranges of ankle dorsiflexion, inversion, and abduction (p < 0.001; p < 0.001; p < 0.003, respectively) between the OLs and the NOLs. Conclusion: Following pilon fracture treatment with the Ilizarov method, we observed no differences in terms of knee or hip joint mobility between the OL and the NOL, whereas the range of motion in the ankle joint of the OL was significantly limited. The treatment of pilon fractures with the Ilizarov method does not ensure the complete normalization of ankle joint kinematic parameters. Therefore, intense personalized rehabilitation of the ankle joint is recommended.

Impairment characteristics of static balance and plantar load distribution of patients undergoing tibial cortex transverse distraction for diabetic foot ulcers

Objective

Tibial cortex transverse distraction (TCTD) has been recently reported for the treatment of diabetic foot ulcers. Herein, we explored the characteristics of the impairments in static balance and plantar load distribution in patients.

Methods

We performed a retrospective study of 21 patients with diabetic foot ulcers who underwent TCTD, who were regularly followed up for > 1 year after surgery, and 20 healthy individuals (control group). A pressure platform was used to assess the standing balance functions of the lower extremities and the plantar load distribution.

Results

One patient underwent amputation because of severe infection. In patient group, center of pressure (COP) ellipse sway area, COP path length and angle θ were all larger, compared with those of control group (250.15 ± 98.36 mm² vs. 135.67 ± 53.21 mm², 145.15 ± 67.43 mm vs. 78.47 ± 34.15 mm, 39.75 ± 17.61° vs. 22.17 ± 14.15°), with statistically significant differences (P < 0.01). The average plantar load and backfoot load of the unaffected side was significantly larger than that of the affected side (58.4 ± 5.5% vs. 41.6 ± 5.5%, 45.3 ± 6.4% vs. 36.5 ± 5.6%), but they were similar for the two feet of members of the control group.

Conclusions

Although TCTD may represent an appropriate method for the treatment of diabetic foot ulcers, postoperative impairments in static balance and plantar load distribution remain in the long term. These potential long-term problems should be taken into account in further rehabilitation planning.

Type of study/level of evidence: Therapeutic III.

Dynamic Gait Parameters in Patients With Nonunion of the Tibia Following Treatment With the Ilizarov Method

The purpose of this study was a comprehensive assessment of the dynamic parameters of gait in patients who underwent Ilizarov treatment for nonunion of the tibia. The experimental group consisted of 24 individuals treated with the Ilizarov method for nonunion of the tibia. The control group comprised 31 healthy individuals, matched for BMI, sex, and age. The dynamic gait parameters in patients and in the control group were measured with a Zebris pedobarographic platform. The treatment group and the control group showed statistically significant differences in terms of the following gait parameters: maximum force during braking nonoperated-limb (NOL), time maximum force during braking operated-limb (OL), time maximum force during braking NOL, maximum force during push-off NOL, time maximum force during push-off OL, and maximum force forefoot OL. Most of the evaluated gait parameters were bilaterally similar in patients group. The only significant differences between the operated and nonoperated limb were seen in terms of Time maximum force during push-off and Maximum force forefoot. The most pronounced abnormalities in dynamic gait parameters were observed in the forefoot (maximum force forefoot OL was 13.3% lower than in the control group, maximum force forefoot OL was 12.4% lower than in NOL). The patients treated with the Ilizarov method did not achieve a complete normalization of dynamic gait parameters, as their gait parameters did not equal those measured in the control group. The Ilizarov method for the treatment of tibial nonunion helps restore a symmetrical distribution of gait parameter values between the affected limb and the healthy limb. Patients continue to show the following abnormalities in their dynamic gait parameters after treatment: higher values maximum force during braking NOL, Time maximum force during braking OL, time maximum force during braking NOL, maximum force during push-off NOL, contact time forefoot NOL, contact time midfoot NOL, contact time heel NOL and smaller values of time maximum force during push-off OL.

3D-printed models improve surgical planning for correction of severe postburn ankle contracture with an external fixator

Gradual distraction with an external fixator is a widely used treatment for severe postburn ankle contracture (SPAC). However, application of external fixators is complex, and conventional two-dimensional (2D) imaging-based surgical planning is not particularly helpful due to a lack of spatial geometry. The purpose of this study was to evaluate the surgical planning process for this procedure with patient-specific three-dimension-printed models (3DPMs). In this study, patients coming from two centers were divided into two cohorts (3DPM group vs. control group) depending on whether a 3DPM was used for preoperative surgical planning. Operation duration, improvement in metatarsal-tibial angle (MTA), range of motion (ROM), the American Orthopedic Foot and Ankle Society (AOFAS) scores, complications, and patient-reported satisfaction were compared between two groups. The 3DPM group had significantly shorter operation duration than the control group ((2.0±0.3) h vs. (3.2±0.3) h, P<0.01). MTA, ROM, and AOFAS scores between the two groups showed no significant differences pre-operation, after the removal of the external fixator, or at follow-up. Plantigrade feet were achieved and gait was substantially improved in all patients at the final follow-up. Pin-tract infections occurred in two patients (one in each group) during distraction and were treated with wound care and oral antibiotics. Patients in the 3DPM group reported higher satisfaction than those in the control group, owing to better patient-surgeon communication. Surgical planning using patient-specific 3DPMs significantly reduced operation duration and increased patient satisfaction, while providing similar improvements in ankle movement and function compared to traditional surgical planning for the correction of SPAC with external fixators.

Body Balance after Fascial Therapy in Athletes with Soft Lower Limb Muscle Injuries

Background: Most injuries in competitive sports are due to overstrain and excessive muscular and fascial tension. This study aimed to assess the effects of a single session of fascial therapy on balance and lower limb weight-bearing in professional athletes following a lower limb soft-tissue injury. Methods: A pedobarographic platform was used to assess the weight-bearing on both lower limbs and corporal balance. A total of 41 athletes with an acute soft-tissue injury involving the quadriceps femoris muscle were included in the study. Each patient underwent myofascial therapy in the injured limb only. The therapy was intended to release tension and improve proprioception. Results: The injured and healthy limbs showed significant asymmetry in body weight distribution. Before treatment, the patients bore less weight on the injured limb than on the healthy limb. After fascial therapy, eyes-closed tests showed an improved weight distribution symmetry between the two lower limbs. There were no significant differences in the values of the evaluated balance parameters between those measured at baseline and those measured after the therapy, measured after the rehabilitation session. Conclusions: A single fascial therapy session has a beneficial effect on corporal balance in runners with an injured lower limb.

Assessment of Lower Limb Load Distribution in Patients Treated with the Ilizarov Method for Tibial Nonunion

Background

Successful treatment of tibial nonunion should lead to a complete bone union, lack of pain, and pathological mobility of the lower extremity, as well as to the achievement of satisfactory joint mobility and muscle strength, which in turn improves its biomechanics. The objective of this study was to assess the load placed on the lower limbs in patients subjected to treatment with the Ilizarov method due to aseptic tibial nonunion.

Material/Methods

This research involved 24 participants (average age, 55 years). All were diagnosed with aseptic tibia nonunion and treated with the Ilizarov external fixator between 2000 and 2017. The control group was matched to the treated group in terms of sex and age. This study used pedobarography evaluation to assess lower limb load distribution.

Results

No differences were found in the distribution of the load over the entire foot or of the forefoot and hindfoot of the treated limb in comparison to the non-dominant limb of the controls, or in the healthy limb of the treated group compared to the dominant limb of the control group. Similarly, differences in load distribution between the operated and healthy limbs of the treated group were insignificant.

Conclusions

Patients subjected to treatment with the Ilizarov external fixator for aseptic tibial nonunion show symmetrical load distribution on both lower limbs following treatment, which does not differentiate them in this respect from healthy individuals. Treated patients presented with a symmetrical distribution of the load on the lower extremities over the entire foot surface, including the forefoot and hindfoot. Finally, the Ilizarov external fixator enables restoration of correct static biomechanics of the treated limbs over the period of aseptic tibial nonunion therapy.

Auto Strut: a novel smart robotic system for external fixation device for bone deformity correction, a preliminary experience

PURPOSE

Several hexapod external fixators are used in the treatment of bone fracture and deformity corrections. One characteristic of all of them is the requirement for manual adjustment of the fixator struts. The purpose of this study was to introduce a novel robotic system that executes automatic adjustment of the struts.

METHODS

Ten patients were treated for various bone deformities using a hexapod external fixator with the Auto Strut system. This new system automatically adjusts the fixator struts according to a hexapod computer-assisted correction plan. During each visit, the progress of the correction was assessed (clinically and radiographically) and reading of the strut scale numbers was performed and compared with the original treatment plan.

RESULTS

All patients completed treatment during the follow-up period, achieving all planned correction goals, except from one patient who switched to manual struts due to personal preference. The device alarm system was activated once with no device-related adverse events. Duration of distraction ranged between ten and 90 days with a distraction index ranging between eight and 15 days/cm. Regenerate consolidation time between one and seven months. In total, 48 struts of eight patients were recorded and analyzed. In all, 94% of the final strut number readings presented a discrepancy of 0 mm to 1 mm between planned and actual readings, indicating high precision of the automatic adjustment.

CONCLUSION

This study presents preliminary results, showing that Auto Strut can successfully replace the manual strut adjustment providing important advantages that benefit the patient, the caregiver and the surgeon.

LEVEL OF EVIDENCE

Level II.

Assessment of Gait after Treatment of Tibial Nonunion with the Ilizarov Method

Background: Tibial nonunion is a common bone union disorder leading to abnormal gait, and thus reducing quality of life in the social dimension. Research question: The aim of our work was to comprehensively assess gait parameters of patients who had undergone Ilizarov treatment for tibial nonunion compared to a control group of healthy individuals. Methods: This study evaluated patients treated for aseptic tibial nonunion with the Ilizarov method. 24 patients with a mean age of 55.0 years were included in the study. The control group consisted of 32 healthy volunteers with no significant medical history who were selected to match the gender and age of patients in the study group so that the groups were homogeneous. A Zebris Medical GmbH pedobarographic platform was used to assess the gait parameters. Results: For all gait parameters examined, force forefoot max, force backfoot max, step length, stance phase, swing phase and step time, we observed statistically significant differences between the group that had undergone treatment and the control group. In the group of patients, statistically significant differences between the operated lower limb and the non-operated limb were only observed for the force forefoot max and step time parameters (p = 0.029 and p = 0.045, respectively). Patients presented a longer loading of the operated limb (0.720 s) than the non-operated limb (0.635 s). For the stride time, step cadence and gait velocity parameters, healthy subjects achieved much better results during locomotion, and these differences were statistically significant at p < 0.001. Significance: Treatment of tibial nonunion with the Ilizarov method did not restore normal gait parameters in our group of patients. In fact, the gait parameters of patients were significantly worse than the healthy individuals in the control group. Furthermore, gait parameters following treatment were not symmetrical, and the dynamics of the musculoskeletal system remained impaired.

Gait Symmetry Analysis in Patients after Treatment of Pilon Fractures by the Ilizarov Method

The aim of this study was to comprehensively assess the gait parameters in patients who had undergone treatment of pilon fractures by the Ilizarov method. We analyzed gait parameters in patients who had undergone treatment for pilon fractures by the Ilizarov method; 20 patients aged 47.0 years (25.2–78.6) were included in the study. The control group consisted of 32 healthy volunteers. Gait examination was performed using the pedobarographic platform. Statistically significant differences in the following gait parameters: maximum forefoot force (%), step length (cm), and step time (s) were found between the study group and the control group, between the nonoperated leg, and both the operated leg and the dominant limb. Statistically significant differences in the study group between the treated lower limb and the healthy lower limb were only observed in the case of the maximum forefoot force parameter (%). Healthy subjects from the control group obtained significantly higher values during locomotion for stride time, cadence step, and velocity than the patients, with stride time being statistically significantly shorter and the velocity and the cadence step higher. We observed symmetry in the gait parameters after treating pilon fractures by the Ilizarov method. This method of stabilization allows the restoration of gait parameters, with results similar to those obtained after the treatment of other motor organ pathologies described in the literature, although different from those observed in healthy subjects. In particular, the biomechanics of the lower limbs remain disturbed.

Contralateral seventh cervical nerve transfer can affect the pennation angle of the lower limb in spastic hemiplegia patients: An observational case series study

INTRODUCTION

We previously reported transferring seventh cervical (C7) nerve from unaffected side to affected side in patients with spastic hemiplegia due to chronic cerebral injury, to improve function and reduce spasticity of paralyzed upper limb. In the clinics, some patients also reported changes of spasticity in their lower limb, which could not be detected by routine physical examinations. Pennation angle of muscle can indirectly reflect the condition of spasticity. The purpose of this study was to evaluate whether this upper limb procedure may affect spasticity of lower limb, using ultrasonography to detect changes of muscle pennation angle (PA).

METHODS

Twelve spastic hemiplegia patients due to cerebral injury including stroke, cerebral palsy, and traumatic brain injury, who underwent C7 nerve transfer procedure, participated in this study. B-mode ultrasonography was used to measure PA of the gastrocnemius medialis (GM) muscle at rest preoperatively and postoperatively. The plantar load distribution of the lower limbs was evaluated using a Zebris FDM platform preoperatively and postoperatively.

RESULTS

The PA of the GM was significantly smaller on the affected side than that of unaffected side before surgery. On the affected side, the postoperative PA was significantly larger than preoperative PA. On the unaffected side, the postoperative PA was not significantly different compared to preoperative PA. The postoperative plantar load distribution of the affected forefoot was significantly smaller than preoperative load distribution, which was consistent with ultrasonography results.

CONCLUSIONS

This study indicates that C7 nerve transfer surgery for improving upper limb function can also affect muscle properties of lower limb in spastic hemiplegia patients, which reveals a link between the upper and lower limbs. The interlimb interactions should be considered in rehabilitation physiotherapy, and the regular pattern and mechanism need to be further studied.