Foot drop caused by lumbar degenerative disease: clinical features, prognostic factors of surgical outcome and clinical stage

Risk factors for reoperation after discectomy of lumbar herniated intervertebral disc disease

Objectives

Discectomy is the most common surgery for lumbar herniated intervertebral disc (HIVD) disease. However, 5%-24% of patients undergo a second surgery due to recurrent disc herniation.

Materials and Methods

This study was aimed to identify the risk factors for reoperation after discectomy of lumbar HIVD and recommend treatment for patients with a high risk of reoperation. We recruited patients diagnosed as having single-level lumbar HIVD who underwent open discectomy from January 1, 2000, to December 31, 2012 in our hospital. We used a survival curve to inspect the survival time and reoperation rate after surgery. We discussed the correlation of reoperation rate with discectomy level, body mass index, heavy lifting after surgery, sex, and age. Furthermore, we investigated the correlation between the experience of a surgeon and the reoperation rate.

Results

A total of 619 patients were enrolled in our study. Most patients were 40-60 years old (48.8%), and most of them had herniation at L4/5 level (48.9%). The 8-year survival rate was 92%. Weight lifting after surgery may increase the reoperation rate by 115 and 18 times for those >60 years and <40 years, respectively. In addition, less experience of the surgeon and female sex had a high reoperation rate.

Conclusion

Postoperative working modification may be very important for preventing patients from recurrent HIVD. For elderly people with HIVD, a more conservative therapy could be selected. If patients with lumbar spine hypermobility or severe degeneration require wide laminectomy, primary fusion should be considered.

Foot drop in critically ill patients: a narrative review of an elusive complication with intricate implications for recovery and rehabilitation

Foot drop is a condition characterized by the inability to lift the foot upwards towards the shin bone. This condition may affect a proportion of critically ill patients, impacting on their recovery after the acute phase of the illness. The occurrence of foot drop in critical care patients may result from various underlying causes, including neurological injuries, muscular dysfunction, nerve compression, or vascular compromise. Understanding the etiology and assessing the severity of foot drop in these patients is essential for implementing appropriate management strategies and ensuring better patient outcomes. In this comprehensive review, we explore the complexities of foot drop in critically ill patients. We search for the potential risk factors that contribute to its development during critical illness, the impact it has on patients' functional abilities, and the various diagnostic techniques adopted to evaluate its severity. Additionally, we discuss current treatment approaches, rehabilitation strategies, and preventive measures to mitigate the adverse effects of foot drop in the critical care setting. Furthermore, we explore the roles of critical care physical therapists, neurologists, and other healthcare professionals in the comprehensive care of patients with foot drop syndrome and in such highlighting the importance of a multidisciplinary approach.

Differential Diagnosis of "Foot Drop": Implications for Peripheral Nerve Surgery

BACKGROUND

 At least 128,000 patients in the United States each year suffer from foot drop. This is a debilitating condition, marked by the inability to dorsiflex and/or evert the affected ankle. Such patients are rendered to a lifetime of relying on an ankle-foot orthosis (AFO) for walking and nighttime to prevent an equinovarus contracture.

METHODS

 This narrative review explores the differential diagnosis of foot drop, with a particular focus on clinical presentation and recovery, whether spontaneously or through surgery.

RESULTS

 Contrary to popular belief, foot drop can be caused by more than just insult to the common peroneal nerve at the fibular head (fibular tunnel). It is a common endpoint for a diverse spectrum of nerve injuries, which may explain its relatively high prevalence. From proximal to distal, these conditions include lumbar spine nerve root damage, sciatic nerve palsy at the sciatic notch, and common peroneal nerve injury at the fibular head. Each nerve condition is marked by a unique clinical presentation, frequency, likelihood for spontaneous recovery, and cadre of peripheral nerve techniques.

CONCLUSION

 The ideal surgical technique for treating foot drop, other than neurolysis for compression, remains elusive as traditional peripheral nerve procedures have been marred by a wide spectrum of functional results. Based on a careful understanding of why past techniques have achieved limited success, we can formulate a working set of principles to help guide surgical innovation moving forward, such as fascicular nerve transfer.

Persistent Radiculopathy Subsequent to Selective Nerve Root Block

Transforaminal selective nerve root blocks are commonly performed for low back pain but are not without risk. This case report describes a 55-year-old man who underwent transforaminal selective nerve root block at the left lumbar (L) 4, L5, and sacral (S) 1 levels for radiating low back pain in the setting of moderate narrowing of the left L4-L5 foramen with impingement on the exiting left L4 nerve roots seen on magnetic resonance imaging (MRI). He developed left foot drop immediately after the procedure and presented to the acupuncture clinic two weeks later with persistent pain, left foot drop, and paresthesia of the left lateral shin. A repeat MRI of the lumbar spine showed mild enhancement of the left cauda equina, including the L5 and possibly L4 nerve roots. The large volume of injection into an area with neuroforaminal narrowing as well as the cytotoxicity of the contrast and anesthetic agents may have contributed to axon damage and left foot drop.

A meta-analysis of prognostic factors in surgical treatment of foot drop due to lumbar degenerative diseases

Objective

Lumbar decompression surgery is an effective treatment for foot drop caused by LDD, but there is controversy about the prognostic factors affecting its efficacy. This study aimed to investigate the factors influencing the surgical outcome of foot drop due to LDD.

Methods

A systematic database search of PubMed, Embase, Web of Science, Cochrane Library and Clinical Trials was performed for relevant articles published until May 2022. Two reviewers independently screened the literature, extracted data, and evaluated the quality of the studies based on the inclusion and exclusion criteria. The quality of the studies was evaluated using the Newcastle-Ottawa Scale (NOS), and STATA 16.0 software was used for meta-analysis.

Results

A total of 730 relevant articles were initially identified and 9 articles were finally included in this study for data extraction and mea-analysis. The results of metaanalysis showed that patients with preoperative moderate muscle strength (2-3/5 on the Medical Research Council scale) had better prognosis compared to those with severe muscle weakness. Additionally, the presence of diabetes mellitus was associated with a poorer prognosis for patients with foot drop due to LDD. The OR values (95%CI) of these two factors were 5.882 (4.449, 7.776) and 5.657 (2.094,15.280) respectively.

Conclusions

Patients with moderate muscle strength have a better prognosis compared to those with severe muscle weakness. The presence of diabetes mellitus is associated with a poorer prognosis for patients with foot drop due to LDD. These factors should be considered when predicting the surgical outcome of foot drop due to LDD.

Can MR neurography of the common peroneal nerve predict a residual motor deficit in patients with foot drop?

OBJECTIVE

To determine if MR neurography of the common peroneal nerve (CPN) predicts a residual motor deficit at 12-month clinical follow-up in patients presenting with foot drop.

MATERIALS AND METHODS

A retrospective search for MR neurography cases evaluating the CPN at the knee was performed. Patients were included if they had electrodiagnostic testing (EDX) within 3 months of imaging, ankle and/or forefoot dorsiflexion weakness at presentation, and at least 12-month follow-up. Two radiologists individually evaluated nerve size (enlarged/normal), nerve signal (T2 hyperintense/normal), muscle signal (T2 hyperintense/normal), muscle bulk (normal/Goutallier 1/Goutallier > 1), and nerve and muscle enhancement. Discrepancies were resolved via consensus review. Multivariable logistical regression was used to evaluate for association between each imaging finding and a residual motor deficit at 12-month follow-up.

RESULTS

Twenty-three 3 T MRIs in 22 patients (1 bilateral, mean age 52 years, 16 male) met inclusion criteria. Eighteen cases demonstrated common peroneal neuropathy on EDX, and median duration of symptoms was 5 months. Six cases demonstrated a residual motor deficit at 12-month follow-up. Fourteen cases underwent CPN decompression (1 bilateral) within 1 year of presentation. Three cases demonstrated Goutallier > 1 anterior compartment muscle bulk. Multivariable logistical regression did not show a statistically significant association between any of the imaging findings and a residual motor deficit at 12-month follow-up.

CONCLUSION

MR neurography did not predict a residual motor deficit at 12-month follow-up in patients presenting with foot drop, though few patients demonstrated muscle atrophy in this study.

Management strategies for the painless foot drop: a systematic review of the literature

PURPOSE

Foot drop can uncommonly be a painless presenting symptom of degenerative spinal disorders. This systematic review aimed to summarise the literature on the management and outcomes of patients with a painless foot drop.

METHODS

We performed a systematic review of PubMed, EMBASE and Medline according to PRISMA guidelines. All studies published after 1980 in English referring to adult patients with a painless foot drop were included. Exclusion criteria included opinion based reports, review articles and articles in which foot drop was not caused by degenerative pathology of the thoracolumbar spine.

RESULTS

Of 62 included patients, 30 (48.4%) were male with an average age of 48.7 years (range 27-84). The mean duration of symptoms was 69.0 days (1-700). 98.8% were managed operatively. 46 (74.2%) patients had symptomatic improvement, with 41 (66.1%) having a post-intervention MRC power grading of 3 or above. Patients with a pre-procedure MRC 0 had a higher median increase in MRC post-procedure than those with MRC > 0. Of two studies comparing painful and painless symptoms, painless foot drop patients were less likely to recover to MRC equal to or over 3 than those with painful symptoms OR 0.31 (95% CI 0.04-2.65).

CONCLUSION

This systematic review and meta-analysis demonstrates a role for surgery in facilitating the neurological recovery of patients with a painless foot drop. Large randomised controlled studies are required to characterise the role of operative intervention in these patients and compare outcomes between patients with painless and painful foot drop.

The treatment effect of posterior lumbar fusion surgery on patients suffering from lumbar disc herniation concurrent with peroneal nerve paralysis

Purpose

The purpose of this study is to investigate the clinical effect of posterior lumbar fusion surgery on patients who suffer from lumbar disc herniation concurrent with peroneal nerve paralysis.

Methods

The patients suffering from peroneal nerve paralysis and undergoing posterior lumbar fusion surgery between January 2012 and December 2019 were retrospectively reviewed. The data of the identified patients were then collected and processed. All patients were followed up post-operatively after discharge from the hospital. The data was analyzed in terms of Oswestry disability index (ODI), visual analogue scale (VAS) score, and relative lower-limb muscle strength.

Results

A total of 87 patients (52 males and 35 females) aged 54 ± 11 years met the inclusion criteria for this study. These patients stayed in hospital for 16 ± 6 days and were followed up for 81 ± 24 months. Data analysis showed that muscle strength of the tibialis anterior and extensor digitorum significantly recovered at the last follow-up with a grade of 3 (median), compared to grade 0 at admission (p < 0.001). Furthermore, the median VAS score decreased to 1 at the last follow-up from 6 at admission (p < 0.001), and the ODI greatly improved with 10% (median) at the last follow-up, while it was 58% at admission (p < 0.001). The ODI improvement rate was 60% on average at the last follow-up. Multivariate regression analysis regarding the ODI and muscle strength improvement rates showed that advanced age was a risk factor for postoperative recovery.

Conclusions

Most of the patients suffering from lumbar disc herniation concurrent with peroneal nerve paralysis can improve after undergoing posterior lumbar fusion surgery, but few can reach full recovery. Advanced age might be a risk factor that affects the prognosis of these patients after surgery.

Time-course gait pattern analysis in a rat model of foot drop induced by ventral root avulsion injury

Foot drop is a common clinical gait impairment characterized by the inability to raise the foot or toes during walking due to the weakness of the dorsiflexors of the foot. Lumbar spine disorders are common neurogenic causes of foot drop. The accurate prognosis and treatment protocols of foot drop are not well delineated in the scientific literature due to the heterogeneity of the underlying lumbar spine disorders, different severities, and distinct definitions of the disease. For translational purposes, the use of animal disease models could be the best way to investigate the pathogenesis of foot drop and help develop effective therapeutic strategies for foot drops. However, no relevant and reproducible foot drop animal models with a suitable gait analysis method were developed for the observation of foot drop symptoms. Therefore, the present study aimed to develop a ventral root avulsion (VRA)-induced foot drop rat model and record detailed time-course changes of gait pattern following L5, L6, or L5 + L6 VRA surgery. Our results suggested that L5 + L6 VRA rats exhibited changes in gait patterns, as compared to sham lesion rats, including a significant reduction of walking speed, step length, toe spread, and swing phase time, as well as an increased duration of the stance phase time. The ankle kinematic data exhibited that the ankle joint angle increased during the mid-swing stage, indicating a significant foot drop pattern during locomotion. Time-course observations displayed that these gait impairments occurred as early as the first-day post-lesion and gradually recovered 7-14 days post-injury. We conclude that the proposed foot drop rat model with a video-based gait analysis approach can precisely detect the foot drop pattern induced by VRA in rats, which can provide insight into the compensatory changes and recovery in gait patterns and might be useful for serving as a translational platform bridging human and animal studies for developing novel therapeutic strategies for foot drop.

A national survey on the management of foot drop secondary to lumbar degenerative disease in the United Kingdom

PURPOSE

There is considerable variation in the management of foot drop secondary to lumbar degenerative disease (LDD) that occurs between centres and surgeons (spinal surgeons and neurosurgeons). The lack of standardised practice reflects the paucity in evidence base for management of this condition. In this survey, we aimed to assess current practice in the UK and identify the areas of variation.

METHODS

A case-based survey was distributed to members of the Society of British Neurological Surgeons and British Association of Spine Surgeons through an online questionnaire. The survey consisted of 10 questions designed to determine the management of foot drop secondary to LDD.

RESULTS

A total of 163 responses were collected among UK neurosurgeons and spinal surgeons with good geographical representation. 92% were Consultants. 86% of the respondents would offer surgery. The indication for offering surgery varied but 54% of respondents would offer surgery to patients who present with a painful foot drop. There was a huge variation in offering surgery dependent on the grade of weakness. The strongest prognostic indicator predicted was duration of weakness (92%). The timing of intervention was wide-ranging in the responses received. Almost all responded that they would be willing to participate in a prospective study in the future to determine best practice.

CONCLUSIONS

This survey highlights the significant variability in management of foot drop secondary to LDD amongst consultant surgeons within the UK. It is also suggestive of a weak evidence base and indicates an urgent need for a high quality national prospective study.

Surgical Treatment of Foot Drop: Pathophysiology and Tendon Transfers for Restoration of Motor Function

Foot drop is a common condition that may impact physical function and health-related quality of life. A detailed clinical history and physical examination are critical components of the initial evaluation of patients presenting with foot drop. Patients with refractory foot drop without spontaneous recovery of motor deficits, delayed presentation greater than 12 months from injury, or neural lesions that are not amenable to or have failed nerve reconstruction may be candidates for tendon transfers to restore active ankle dorsiflexion. The modified Bridle procedure is a dynamic tendon transfer that has demonstrated excellent functional outcomes in patients with refractory foot drop.

A Novel Capsule Lumbar Interbody Fusion (CLIF) in Treating Foot Drop due to Lumbar Degenerative Diseases: a Prospective, Observational Study

Objective

This present study aimed to explore the clinical effects of a novel capsule lumbar interbody fusion (CLIF) on foot drop due to lumbar degenerative diseases.

Methods

Between June 2018 and January 2019, a total of 27 patients admitted to our department with lumbar degenerative diseases with associated foot drop were prospectively enrolled. Given the selection of surgical technique, patients were divided into traditional TLIF group and CLIF group. We assessed patients' neurological status using JOA and VAS score, tibialis anterior muscle strength using MMT score, diameter and hemodynamic parameters of the L5 nerve root using intraoperative ultrasonography (IoUS), and related radiological parameters of the lumbar spine. Operation time, blood loss, and surgery-associated complications were also recorded.

Results

The median duration of follow-up was 150 (6–1460) months. At the final follow-up, all patients acquired satisfactory improvement of neurological function. However, patients in the CLIF group showed better early recovery of foot drop three months after operation than those in the TLIF group, with 75% excellent rate. In addition, IoUS suggested that the diameter and hemodynamic parameters of the L5 nerve root were improved better in the CLIF group, which may suggest the correlation between the recovery of foot drop and the status of L5 nerve root. No severe complications were encountered with CLIF.

Conclusions

Our preliminary study revealed that the axial tension of L5 nerve root may be involved in the pathological mechanism of foot drop. The novel technique of CLIF can shorten the lumbar spine and can be effective and safe for the treatment of foot drop due to lumbar degeneration-related diseases.

Surgical decompression timing for patients with foot drop from lumbar degenerative diseases: a meta-analysis

OBJECTIVE

To compare the outcomes of early (within 1 month after foot drop) decompression versus late (1 month or more after foot drop) decompression in order to determine the optimal surgical intervention timing for lumbar degenerative diseases.

METHODS

The MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science and SCOPUS electronic databases were searched for relevant articles published until May 2021 were conducted. Cochrane Collaboration guidelines were used for data extraction and quality assessment. Outcomes of interest were manual muscle testing (MMT) and recovery rate (MMT ≥ 4) for foot drop in lumbar degenerative diseases.

RESULTS

Six clinical studies were retrieved, including 312 randomized participants. One hundred fifty-seven patients underwent early decompression surgery, and 155 underwent late decompression surgery. There were significant differences between the two groups in recovery rate (95% confidence interval [CI] 1.59, 2.57) and neurological improvement (95% confidence interval [CI] 0.21, 1.66). Early surgical decompression provided better recovery rate and neurological improvement for foot drop in lumbar degenerative diseases than late surgical decompression.

CONCLUSION

Early surgical decompression within was beneficial in terms of recovery rate and neurological improvement compared with late surgery. Early surgical decompression (within 1 month) is recommended for patients with foot drop in lumbar degenerative diseases.

Prognostic indicators of surgical outcome in painful foot drop: a systematic review and meta-analysis

PURPOSE

Foot drop is a relatively uncommon presentation of lumbar degenerative disease and there is currently a paucity of evidence on management and outcomes which is reflective of the lack of standardised treatment provided to patients. The purpose of this systematic review and meta-analysis is to determine the effectiveness of surgical management and the factors that predict surgical outcome.

METHODS

A systematic database search of Cochrane Library, Ovid Medline, Pubmed, Embase and Google Scholar was undertaken from inception through August 2018. Only studies reporting on surgical outcome in adult patients who had a painful foot drop and underwent decompression were included. Case reports and studies with surgical fixation were excluded. Study quality was assessed using the Newcastle-Ottawa Scale. Data were pooled using a random-effects model.

RESULTS

797 studies were screened and 9 observational studies met the inclusion criteria. This resulted in a total of 431 patients who underwent decompression for foot drop. Pooled rates of outcome for improvement in foot drop MRC grade were 84.5% (range 67.9-96%). Sub-group meta-analyses of studies revealed a statistically significant association between duration of foot drop (pooled 4.95 [95% CI 1.13-21.74]), severity of preoperative weakness (pooled 0.38 [95% CI 0.15-0.93]) on post-operative outcome and age (pooled 6.28 [1.33-29.72]).

CONCLUSION

This is the first systematic review and meta-analysis to explore the outcome and prognostic indicators of lumbar decompression for foot drop. Findings indicate that age, duration of foot drop weakness and MRC grade of foot drop prior to intervention were strong predictors of surgical outcome.

Transpedicular or Transthoracic Approach: An Outcome Comparison Study on Patients with Neurological Manifestation

Background: Approach to lower-thoracic spine for discectomy remains controversial. In this study, we compare primary and secondary outcomes of transpedicular (TP) and transthoracic (TT) approach for discectomy at lower thoracic levels in patients with neurological manifestations. Methods: In this retrospective study, 12 patients with TP or TT approach for lower thoracic discectomy with neurological manifestation, mainly foot drop, were included. During TP approach, cord manipulation was kept at minimum. Posterior fusion was performed in all patients. TT approach was performed by intended level thoracotomy, anterio-lateral fusion was achieved in this group. The postoperative primary and secondary outcomes of the approach were compared in these patients. SPSS software version 20 was used for analysis, and a P-value < 0.005 was considered significant. Results: Twelve patients with neurological manifestation were operated using either of the approaches. Six patients in TP group and four in TT group attained complete neurological recovery after 10.2 and 7.6 weeks, respectively. The mean operative time was 50% more in TT approach. Blood loss in TP approach was less than half, and patients were mobilized earlier with decreased hospital stay. All patients with TT approach needed postoperative intensive care unit (ICU) admission, two of them developed pulmonary complications and postsurgical intercostal neuralgia, and one had cerebrospinal fluid (CSF) leak and readmission within 30 days of discharge. Conclusions: Although TT approach offers excellent exposure for discs in lower thoracic levels, it is associated with increased morbidity and higher complication rates. On the other hand, TP approach offers ample exposure with reduced operative time and blood loss, as well as early mobilization and discharge.

The Clinical Effect of a Combination of Mouse Nerve Growth Factor and Methylcobalamin to Treat Lumbar Disc Herniation with Foot Drop: A Retrospective Cohort Study

Objective

To investigate the clinical effect of mouse nerve growth factor (mNGF) and methylcobalamin (MeCbl) for the treatment of lumbar disk herniation (LDH) with foot drop.

Methods

A total of 46 patients suffering from LDH with foot drop who underwent transforaminal lumbar interbody fusion (TLIF) surgery in our department from January 2015 to December 2017 were retrospectively analyzed. We divided these patients into two groups according to the different postoperative treatment which independently selected by patients after signing informed consent form: one group of 25 patients was treated with MeCbl alone (Group MeCbl), the other group of 21 patients was treated with a combination of mNGF and MeCbl (Group MeCbl+mNGF). Patient demographics, the visual analogue scale (VAS) scores, sensory and muscular strength improvement statistics at 1 week, 4 weeks, 12 weeks, and 12 months postoperatively were recorded. Motor/sensory deficits, sciatica and overall neurological outcome after treatment of MeCbl alone and combination of mNGF and MeCbl were retrospectively analyzed.

Results

The follow‐up ranged between 12 and 42 months (mean 20.8 months). There were no significant differences between these two groups of patients with respect to sex ratio, age, smoking, diabetes, disease course, section of protruding disc(s), muscular strength of foot dorsiflexion or preoperative visual analogue scale (VAS) score (P > 0.05). The VAS scores of Group MeCbl+mNGF were significantly lower than Group MeCbl at 1 week, 4 weeks, 12 weeks, and 12 months postoperatively (4.32 ± 0.75 vs 5.25 ± 0.79,2.65 ± 0.48 vs 3.42 ± 0.52, 1.72 ± 0.36 vs 2.45 ± 0.39, 1.12 ± 0.22 vs 1.52 ± 0.24, P < 0.05). The effective rates of sensory improvement were significantly higher in Group MeCbl+mNGF compared with Group MeCbl at 12‐week/12‐month follow‐up time point (90.48% vs 52.00%,95.24% vs 68.00%, P < 0.05). The effective rate of muscular strength improvement of the two groups did not differ significantly at 1 week after surgery but exhibited statistically significant differences at subsequent time points (61.90% vs 32.00%, 76.19% vs 44.00%, 80.95% vs 48.00%, P < 0.05).

Conclusions

Application of mNGF had clinical effects on promoting the recovery of neurological function in patients suffering from LDH with foot drop.

Amelioration of lower limb pain and foot drop with 10 kHz spinal cord stimulation: A case series

There are limited treatment options for patients with foot drop and associated lower back and/or leg pain. We present a case series of three patients who received permanent implantation of 10 kHz spinal cord stimulation (10 kHz SCS) devices. Following treatment, all patients reported sustained improvements in lower back and leg pain, foot mechanics and function which resulted in increased mobility and cessation of opioid use for pain management. Patients were followed up for approximately four years. Treatment with 10 kHz SCS may be a promising alternative to other interventional procedures commonly used for these patients.

Drop foot due to lumbar degenerative disease: Painless drop foot is difficult to recover

OBJECTIVE

To evaluate the improvement of drop foot following lumbar decompression surgery and determine the prognostic factors that might influence the recovery of drop foot.

SUMMARY AND BACKGROUND DATE

Drop foot is a common but serious problem that can lead to deteriorate patient's daily activities. There are numerous studied regarding the prognostic factors for the recovery of drop foot. However a few reports have been described the pathophysiological etiology of not only drop foot but also Trendelenburg's sign due to the L5 nerve root palsy. Therefore, there is a possibility drop foot caused by peroneal nerve palsy is included. In addition, none have evaluated the presence or absence of radicular leg pain with drop foot patients. The purpose of this study was to evaluate the improvement of paretic leg muscles and determine the prognostic factors that might influence the recovery of drop foot.

METHODS

Fifty-five drop foot patients were included in the study. Prognostic factors were retrospectively studied.Patients were assessed in terms of 10 items: 1) age, 2) sex, 3) diagnosis (LDH or LSS), 4) muscle strength of tibialis anterior, 5) muscle strength of extensor halluces longus, 6) muscle strength of gluteus medius, 7) presence or absence of radicular leg pain, 8) duration before surgery, 9) surgical treatment (spinal fusion or not), 10) anamnesis of diabetes mellitus.

RESULTS

Thirty-two (58.2%) of 55 patients recovered from their drop foot (manual muscle test of tibialis anterior ≥ 4 at final follow-up), while 23 (41.8%) did not (manual muscle test of tibialis anterior ≤ 3 at final follow-up). The strength of all muscles that were innervated and controlled by the L5 nerve root had recovered at the final follow-up when evaluated as averages. Multivariate logistic regression analysis revealed significant differences in terms of 2 items: "duration before surgery" and "presence or absence of radicular leg pain".

CONCLUSIONS

"Duration before surgery" and "presence or absence of radicular leg pain" are important to predict the recovery of drop foot. Painless drop foot patients with lumbar degenerative disease are difficult to recover their paralysis.

Classification and prognostic factors of residual symptoms after minimally invasive lumbar decompression surgery using a cluster analysis: a 5-year follow-up cohort study

PURPOSE

Residual symptoms indicating incomplete remission of lower leg numbness or low back pain may occur after spine surgery. The purpose was to elucidate the pattern of residual symptoms 5 years after minimally invasive lumbar decompression surgery using a cluster analysis.

METHODS

The study comprised 193 patients with lumbar spinal stenosis (LSS) (108 men, 85 women) ranging in age from 40 to 86 years (mean, 67.9 years). Each patient underwent 5-year follow-up. The Japanese Orthopedic Association score and visual analog scale scores for low back pain, leg pain, and leg numbness at 5 years were entered into the cluster analysis to characterize postoperative residual symptoms. Other clinical data were analyzed to detect the factors significantly related to each cluster.

RESULTS

The analysis yielded four clusters representing different patterns of residual symptoms. Patients in cluster 1 (57.0%) were substantially improved and had few residual symptoms of LSS. Patients in cluster 2 (11.4%) were poorly improved and had major residual symptoms. Patients in cluster 3 (17.6%) were greatly improved but had mild residual low back pain. Patients in cluster 4 (14.0%) were improved but had severe residual leg numbness. Prognostic factors of cluster 2 were a short maximum walking distance, motor weakness, resting lower leg numbness, cofounding scoliosis, and high sagittal vertical axis.

CONCLUSIONS

This is the first study to identify specific patterns of residual symptoms of LSS after decompression surgery. Our results will contribute to acquisition of preoperative informed consent and identification of patients with the best chance of postoperative improvement.

Evaluation and Treatment of Foot Drop Using Nerve Transfer Techniques

Foot drop represents a complex pathologic condition, requiring a multidisciplinary approach for appropriate evaluation and treatment. Multiple etiologic factors require recognition before considering invasive/operative intervention. When considering surgical management for the treatment of foot drop, it is first and foremost imperative to establish the cause of the condition. Not all causes resulting in clinical foot drop have surgical options. Establishing a cause allows the provider to more appropriately curtail a multidisciplinary approach to working-up, and ultimately, treating the patient. The authors offer an algorithm for evaluating and treating foot drop conditions associated with lumbar spine radiculopathy and peripheral nerve lesions.

Percutaneous Discectomy Followed by CESI Might Improve Neurological Disorder of Drop Foot Patients Due to Chronic LDH

(1) Introduction: Epiconus and conus medullary syndromes that consisted of drop foot, pain, numbness, bladder or bowel dysfunction are serious problems might be caused by lumbar disc(s) herniation (LDH) compression. (2) Objective: To evaluate percutaneous discectomy effectivity for decompressing LDH lesions. (3) Case Report: Three patients suffered from drop feet, numbness, and bowel and bladder problems due to LDH compression. Patient #1 is a male (35 years old, basal metabolism index (BMI) = 23.9), point 1 on manual muscle test (MMT), with protrusion on L3 to S1 discs; Patient #2 is a female (62 years old, BMI = 22.4), point 3 on MMT, with protrusion on L2-4 and L5-S1 discs; Patient #3 is a female (43 years old, BMI = 26.6), point 4 on MMT, with extrusion on T12-L1 and L1-2 and L3-4 protruded discs. Six months follow-up showed of stand and walkability improvement with Patient #1 and #2. Patient #3 showed improvement in bowel and bladder problems within 10 weeks, without suffering of postoperative pain syndromes. (4) Discussion: Patient #1 and #2 showed better outcomes than Patient #3 who affected epiconus and cauda equina syndromes. Triamcinolone and lidocaine have analgesic and anti-inflammatory properties for improving intraepidural circulation adjacent to the lesion sites. (5) Conclusion: Drop foot caused by mechanical compression of LDH ought to be treated immediately. Lateral or posterolateral compression has better outcomes associated with anatomical structures. Discectomy through transforaminal approach that is followed by caudal epidural steroid injection (CESI) under fluoroscopic guidance is a safer and minimally invasive treatment with promising outcomes.

A review on the orthotics and prosthetics and the potential of kenaf composites as alternative materials for ankle-foot orthosis

Since ancient Egypt, orthosis was generally made from wood and then later replaced with metal and leather which are either heavy, bulky, or thick decreasing comfort among the wearers. After the age of revolution, the manufacturing of products using plastics and carbon composites started to spread due to its low cost and form-fitting feature whereas carbon composite were due to its high strength/stiffness to weight ratio. Both plastic and carbon composite has been widely applied into medical devices such as the orthosis and prosthesis. However, carbon composite is also quite expensive, making it the less likely material to be used as an Ankle-Foot Orthosis (AFO) material whereas plastics has low strength. Kenaf composite has a high potential in replacing all the current materials due to its flexibility in controlling the strength to weight ratio properties, cost-effectiveness, abundance of raw materials, and biocompatibility. The aim of this review paper is to discuss on the possibility of using kenaf composite as an alternative material to fabricate orthotics and prosthetics. The discussion will be on the development of orthosis since ancient Egypt until current era, the existing AFO materials, the problems caused by these materials, and the possibility of using a Kenaf fiber composite as a replacement of the current materials. The results show that Kenaf composite has the potential to be used for fabricating an AFO due to its tensile strength which is almost similar to polypropylene's (PP) tensile strength, and the cheap raw material compared to other type of materials.

Factors Affecting Early and 1-Year Motor Recovery Following Lumbar Microdiscectomy in Patients with Lumbar Disc Herniation: A Prospective Cohort Review

Study Design

Prospective cohort study.

Purpose

The study was aimed at evaluating clinicoradiological factors affecting recovery of neurological deficits in cases of lumbar disc herniation (LDH) treated by lumbar microdiscectomy.

Overview of Literature

The majority of the available literature on neurological recovery following neurodeficit is limited to retrospective series. The literature is currently limited regarding variables that can help predict the recovery of neurodeficits following LDH.

Methods

A prospective analysis was performed on 70 consecutive patients who underwent lumbar microdiscectomy (L1–2 to L5–S1) owing to neurological deficits due to LDH. Patients with motor power ≤3/5 in L2–S1 myotomes were considered for analysis. Follow-up was performed at 2, 6, and 12 months to note recovery of motor deficits. Clinicoradiological parameters were compared between the recovered and nonrecovered groups.

Results

A total of 65 patients were available at the final follow-up: 41 (63%) had completely recovered by 2 months; four showed delayed recovery at the 6-month follow-up; and 20 (30.7%) showed no recovery at 1 year. Clinicoradiological factors, including diabetes, complete initial deficit, areflexia, multilevel disc prolapse, longer duration since initial symptoms, and ≥2 previous symptomatic episodes were associated with a significant risk of poorer recovery (p<0.05 for all). Age, sex, occupation, smoking, level/type or location of disc herniation, primary canal stenosis, disc fragment dimensions, precipitating factors, bladder involvement, bilaterality of symptoms, and the presence or absence of anal reflex did not affect neurological recovery (p>0.05 for all). Diabetes mellitus (p=0.033) and complete initial motor deficit (p=0.028) were significantly associated with delayed recovery in the multivariate analysis.

Conclusions

The overall neurological recovery rate in our study was 69%. Diabetes mellitus (p=0.033) and complete initial motor deficit were associated with delayed motor recovery.

Spontaneous Recovery of Complete Foot Drop in Case of Lumbar Disk Herniation: Catcher in the Rye?

BACKGROUND

Foot drop is defined as inability to dorsiflex the foot at the ankle joint. Although a well-documented entity with a myriad of causes along the neuraxis, starting from parasagittal intracranial pathologies to peripheral nerve lesions, treatment has always remained uniform (i.e., elimination of the causative pathology. A conservative approach with complete recovery has never been documented with video evidence).

CASE DESCRIPTION

A 74-year-old female presented with dorsiflexion weakness of the left ankle secondary to a prolapsed disk at the L4-5 level. The duration of the foot drop was short (3 days). She was planned for surgery but kept under close observation considering the consistent recovery of the symptoms. To our astonishment she had rapid pain relief in the next 5 days. Motor power improved over 3 weeks, and she had complete recovery in 4 weeks. Video recordings were made to document the improved power at both stages.

CONCLUSIONS

Spontaneous recovery of complete foot drop is possible, and there is a role for the conservative management even with dense neurologic deficit in cases of lumbar disk herniation. Careful repeated examination is the key for conservative management before jumping to aggressive surgical intervention.

Metachronous Bilateral Painless Foot Drop Secondary to Spinal Stenosis: Case Report

Foot drop (FD) is an uncommon manifestation of nerve root compression secondary to lumbar degenerative disease (LDD). In most of these patients, FD is unilateral and is associated with low back pain and leg pain. A small number of cases have been described with bilateral FD, which is reported to occur simultaneously in a synchronous fashion. A 63-year-old male with a remote history of spinal surgery due to left painless FD presented with a new episode of right FD, this new FD initiated suddenly and it was not associated with low back pain or radicular pain. Magnetic resonance imaging (MRI) showed bilateral lumbar stenosis at L3-4 and subarticular stenosis at right L4-5 level causing compression of right L5 nerve root. Fenestrations, removal of flavum ligament and medial facetectomy were performed bilaterally at L3-4 and on the right side at L4-5 level. Postoperatively, the patient experienced progressive improvement on right foot dorsiflexion. The occurrence of bilateral painless FD presenting in a metachronous way as observed in the present case is a very unusual scenario. To the best of author’s knowledge, cases with these characteristics have not been previously reported.

Development of a Predictive Score for Discharge Disposition After Lumbar Fusion Using the Quality Outcomes Database

BACKGROUND

Lumbar fusion remains the treatment of choice for many degenerative pathologies. Healthcare costs related to the procedure are a concern, and postdischarge needs often contribute to greater expenditure. The Quality Outcomes Database (QOD) is a prospective, multicenter clinical registry designed to analyze outcomes after neurosurgical procedures.

OBJECTIVE

To create a simple scoring system to predict discharge needs after lumbar fusion.

METHODS

Institutional QOD data from 2 high-volume neurosurgical centers were collected retrospectively. Univariate and multivariable logistic regression analyses were used to identify factors for our model. A receiver operating characteristic curve was used to set cutoff scores for patients likely to discharge home without ongoing services and those likely to require additional services/alternative placement after discharge.

RESULTS

Two hundred seventeen patients were included. Five variables—osteoporosis, predominant preoperative symptom, need for assistive ambulation device, American Society of Anesthesiologist grade, and age—were included in our final scoring system. Patients with higher scores are less likely to need additional services. In patients with high scores (8-10), our scale correctly predicted discharge needs in 88.7% of cases. In patients with low scores (0-5), our scale predicted discharge needs (additional home services/alternative placement) in 75% of cases. For our final instrument, the area under the receiver operating characteristic curve was 0.809 (95% confidence interval 0.720-0.897).

CONCLUSION

We present a simple scoring system to assist in predicting postdischarge needs for patients undergoing lumbar fusion for degenerative disease. Further validation studies are needed to assess the generalizability of our scale.

Differential diagnosis and recovery of acute bilateral foot drop in a patient with a history of low back pain: A case report

BACKGROUND AND PURPOSE

Acute bilateral foot drop is rare and may be due to peripheral or central lesions. The purpose of this case report was to describe the differential diagnosis and recovery of a patient with low back pain (LBP) that awoke with bilateral foot drop.

CASE DESCRIPTION

A 39-year-old man with a history of LBP awoke with a steppage gait pattern. Spinal imaging and tapping were negative for sinister pathologies. A subsequent history taken by the physical therapist uncovered that the patient had previously taken a narcotic and slept in a kneeling position to relieve his LBP. Strength and sensory testing revealed isolated impairments in the fibular nerve distribution, and bilateral fibular palsy was suspected and later confirmed with electrophysiological studies. Surgical fibular nerve decompression was performed, and the patient underwent physical therapy.

OUTCOMES

Five months later the patient demonstrated antigravity strength and a partial return of sensation. By 17 months, his Lower Extremity Functional Scale had improved from 17/80 to 78/80, revealing a near complete recovery.

DISCUSSION

The patient's history of LBP was a "red herring" that delayed the diagnosis and caused undue stress to the patient. This case stresses the importance of a thorough history and clinical examination.

Prediction of Postoperative Clinical Recovery of Drop Foot Attributable to Lumbar Degenerative Diseases, via a Bayesian Network

BACKGROUND

Drop foot resulting from degenerative lumbar diseases can impair activities of daily living. Therefore, predictors of recovery of this symptom have been investigated using univariate or/and multivariate analyses. However, the conclusions have been somewhat controversial. Bayesian network models, which are graphic and intuitive to the clinician, may facilitate understanding of the prognosis of drop foot resulting from degenerative lumbar diseases.

QUESTIONS/PURPOSES

(1) To show a layered correlation among predictors of recovery from drop foot resulting from degenerative lumbar diseases; and (2) to develop support tools for clinical decisions to treat drop foot resulting from lumbar degenerative diseases.

METHODS

Between 1993 and 2013, we treated 141 patients with decompressive lumbar spine surgery who presented with drop foot attributable to degenerative diseases. Of those, 102 (72%) were included in this retrospective study because they had drop foot of recent development and had no diseases develop that affect evaluation of drop foot after surgery. Specifically, 28 (20%) patients could not be analyzed because their records were not available at a minimum of 2 years followup after surgery and 11 (8%) were lost owing to postoperative conditions that affect the muscle strength evaluation. Eight candidate variables were sex, age, herniated soft disc, duration of the neurologic injury (duration), preoperative tibialis anterior muscle strength (pretibialis anterior), leg pain, cauda equina syndrome, and number of involved levels. Manual muscle testing was used to assess the tibialis anterior muscle strength. Drop foot was defined as a tibialis anterior muscle strength score of less than 3 of 5 (5 = movement against gravity and full resistance, 4 = movement against gravity and moderate resistance, 3 = movement against gravity through full ROM, 3- = movement against gravity through partial ROM, 2 = movement with gravity eliminated through full ROM, 1 = slight contraction but no movement, and 0 = no contraction). The two outcomes of interest were postoperative tibialis anterior muscle strength (posttibialis anterior) of 3 or greater and posttibialis anterior strength of 4 or greater at 2 years after surgery. We developed two separate Bayesian network models with outcomes of interest for posttibialis anterior strength of 3 or greater and posttibialis anterior strength of 4 or greater. The two outcomes correspond to "good" and "excellent" results based on previous reports, respectively. Direct predictors are defined as variables that have the tail of the arrow connecting the outcome of interest, whereas indirect predictors are defined as variables that have the tail of the arrow connecting either direct predictors or other indirect predictors that have the tail of the arrow connecting direct predictors. Sevenfold cross validation and receiver-operating characteristic (ROC) curve analyses were performed to evaluate the accuracy and robustness of the Bayesian network models.

RESULTS

Both of our Bayesian network models showed that weaker muscle power before surgery (pretibialis anterior ≤ 1) and longer duration of neurologic injury before treatment (> 30 days) were associated with a decreased likelihood of return of function by 2 years. The models for posttibialis anterior muscle strength of 3 or greater and posttibialis anterior muscle strength of 4 or greater were the same in terms of the graphs, showing that the two direct predictors were pretibialis anterior muscle strength (score ≤ 1 or ≥ 2) and duration (≤ 30 days or > 30 days). Age, herniated soft disc, and leg pain were identified as indirect predictors. We developed a decision-support tool in which the clinician can enter pretibialis anterior muscle strength and duration, and from this obtain the probability estimates of posttibialis anterior muscle strength. The probability estimates of posttibialis anterior muscle strength of 3 or greater and posttibialis anterior muscle strength of 4 or greater were 94% and 85%, respectively, in the most-favorable conditions (pretibialis anterior ≥ 2; duration ≤ 30 days) and 18% and 14%, respectively, in the least-favorable conditions (pretibialis anterior ≤ 1; duration > 30 days). On the sevenfold cross validation, the area under the ROC curve yielded means of 0.78 (95% CI, 0.68-0.87) and 0.74 (95% CI, 0.64-0.84) for posttibialis anterior muscle strength of 3 or greater and posttibialis anterior muscle strength of 4 or greater, respectively.

CONCLUSIONS

The results of this study suggest that the clinician can understand intuitively the layered correlation among predictors by Bayesian network models. Based on the models, the decision-support tool successfully provided the probability estimates of posttibialis anterior muscle strength to treat drop foot attributable to lumbar degenerative diseases. These models were shown to be robust on the internal validation but should be externally validated in other populations.

LEVEL OF EVIDENCE

Level III, therapeutic study.