THE CONUNDRUM OF CLAUDICATION

Spinal Cord Stimulation Improves the Microvascular Perfusion Insufficiency Caused by Critical Limb Ischemia

OBJECTIVE

This retrospective case-controlled study intended to identify the benefits and efficacy of spinal cord stimulation (SCS) as a therapeutic strategy for patients with perfusion problems caused by critical limb ischemia (CLI). The outcomes of patients who received SCS were compared with those of patients who did not receive SCS.

METHODS

This study recruited 78 patients who were diagnosed with perfusion problems over the period of 2003-2011. Lower-limb Thallium-201 (²⁰¹ Tl) scintigraphy revealed that the patients exhibited a perfusion difference of <0.95. Thirty-seven of the recruited patients received SCS treatment and 41 did not receive SCS treatment. All patients received the same medication: 100 mg aspirin once a day and 500 mg paracetamol thrice a day. The outcomes of walking distance, walking time, and sleeping quality were measured and recorded. Pain intensities were evaluated using the visual analog scale (VAS) scoring system.

RESULTS

Prior to SCS implantation, patients in the SCS treatment group had worse walking distance (64.86 ± 40.80 vs. 613.70 ± 535.00, p < 0.001), walking time (2.65 ± 1.64 vs. 13.90 ± 11.91, p < 0.001), and sleep quality (1.70 ± 0.78 vs. 3.32 ± 1.17, p < 0.001) than patients in the non-SCS treatment group. At the one-year follow-up, however, patients in the SCS treatment group had significantly better walking distance (1595.00 ± 483.60, p < 0.001), walking time (48.92 ± 14.10, p < 0.001), and sleep quality (4.65 ± 0.92, p < 0.001) than patients in the non-SCS treatment group. Moreover, the VAS score of patients in the SCS treatment group improved one week (8.63 ± 0.54 vs. 4.48 ± 0.59, p < 0.001) and one year after SCS implantation (2.35 ± 0.62, p < 0.001). By contrast, at the one-year follow-up, the walking distance (277.60 ± 374.80, p = 0.002), walking time (9.44 ± 10.73, p = 0.078), sleep quality (2.20 ± 1.10, p < 0.001), and VAS score (7.98 ± 0.43, p = 0.020) of patients in the non-SCS treatment group worsened. Furthermore, lower-limb ²⁰¹ Tl scintigraphy revealed that microcirculation intensity increased in the lower extremities of patients in the SCS treatment group after SCS implantation relative to that before SCS implantation. Most importantly, 10 of the 41 patients in the non-SCS treatment group required the use of wheelchairs, whereas none of the patients in the SCS treatment group required the use of wheelchairs.

CONCLUSION

Treatment of CLI patient with SCS improved patient's walking ability, pain severity, and sleep quality. SCS should be considered as an effective treatment toward limb salvage in CLI.

Insights Into Microcirculation Underlying Critical Limb Ischemia by Single-Photon Emission Computed Tomography

Perfusion difference is used as a parameter to evaluate microcirculation. This study aims to differentiate lower-limb perfusion insufficiency from neuropathy to prevent possible occurrence of failed back surgery syndrome (FBSS).Patients were retrospectively gathered from 134 FBSS cases diagnosed in the past 7 years. Up to 82 cases that were excluded from neuralgia by radiologic imaging, electrodiagnostic electromyography, and nerve conduction velocity were enrolled in this study. Perfusion difference was evaluated by single-photon emission computed tomography, and pain intensities were recorded via visual analog scale (VAS) score.Lower perfusion at the left leg comprises 51.2% (42 of 82) of the patients. The mean perfusion difference of the 82 patients was 0.86 ± 0.05 (range: 0.75-0.93). Patients with systemic vascular diseases exhibited significantly higher perfusion difference than that of patients without these related diseases (P < 0.05), except for renal insufficiency (P = 0.134). Significant correlation was observed between perfusion difference and VAS score (r = -0.78; P < 0.0001; n = 82).In this study, we presented perfusion difference as a parameter for evaluating microcirculation, which cannot be detected by ultrasonography or angiography.

Basic data underlying decision making in nonatherosclerotic causes of intermittent claudication

Although most cases of vasculogenic intermittent claudication are caused by atherosclerosis, there is an important minority of cases that are due to nonatherosclerotic causes. Because of their rarity and younger population affected, often without traditional atherosclerotic risk factors, there is frequently a significant delay in diagnosis of nonatherosclerotic peripheral arterial diseases by several months to years in some cases. Here, we review the literature on nonatherosclerotic causes of lower extremity claudication, symptoms, management including surgical and endovascular interventions, and outcomes. Conditions included are popliteal artery entrapment syndrome, cystic adventitial disease, pseudoxanthoma elasticum, persistent sciatic artery, fibromuscular disease, giant cell arteritis, iliac endofibrosis, neurogenic claudication, and chronic exertional compartment syndrome.

Lower limb pain caused by insufficient muscular microcirculation

Lumbar spinal surgery is a common procedure to treat low back pain. To remark that lower limb perfusion insufficiency may induce the similar syndrome as neuropathic pain, 1,076 cases of postspinal surgery was surveyed within 5 years, in which 51 cases had no obvious improvement 3 months after surgery; 27 cases received second operation because of instability, inadequate decompression, and wrong level; and the other 27 cases including 3 cases after twice spinal surgeries were enrolled. Physical examinations were presented with atypical neuropathic pain and muscle wasting at single lower limbs which deteriorated with long-distance walking. Computed tomography or magnetic resonance imaging scan was studied including the neural structure and lower limb angiography. The report showed degenerative change without definite neural structural compression or vascular occlusion. There was also no significant finding of electrodiagnostic study. The rest radionuclide study of lower limb muscle and myocardium was performed in these 27 cases using Thallium-201. All patients presented 9-24 % (~14%) muscle perfusion difference compared with two legs. Most of peripheral arterial occlusion disease cases presented the symptoms with ischemic pain and vascular claudication. In the study, the patients presented not only ischemic limb but also the bizarre symptoms, such as low back pain with or without radiating root pain and sensory disturbance. Physicians should be aware of the possibility of lower limb pain caused by lower perfusion syndrome.