Intramedullary holocord abscess secondary to infected dermoid cyst.

In the literature, less than ten cases of holocord intramedullary abscess in children have been described. A 15-month-old girl presented with flaccid paraplegia and dermal sinus in the sacral region. MRI highlighted an infected lumbar dermoid cyst. The child underwent surgery to remove the cyst and purulent collection. Five days after surgery, she developed upper limbs paresis. An MRI showed a holocord abscess. A catheter was inserted through a cervical myelotomy into the abscess for drainage with a good postoperative recovery. A rapid management, even for extended or recurrent intramedullary abscess, can prevent potential severe neurological dysfunctions.

A Rare Case of Streptococcus cristatus Spondylodiscitis Identified by Bacterial 16S rRNA Polymerase Chain Reaction Sequencing: A Case Report and a Review of the Literature.

We report here a rare case of spondylodiscitis due to Streptococcus cristatus in a healthy 66-year-old male. Due to an abscess causing neurological deficit, which required immediate surgical intervention, a PCR targeting 16S rRNA was performed on the surgical samples as all blood and tissue cultures remained negative. This molecular assay allowed for the identification of this rare Streptococcus, a member of the mitis group and commensal of the oral cavity, whose pathogenicity remains uncertain although it has been seldom reported in cases of human infections, mostly bacteremia and endocarditis. Notably, our case is distinguished by the absence of comorbidities, although the patient's history was compatible with a dental portal of entry. This case illustrates once more that 16S rRNA PCR can be of great help for documenting the causative pathogen in osteoarticular infections when cultures remain inconclusive. We reviewed in this article the data regarding osteoarticular infections due to S. cristatus and discussed the role of molecular technique in the diagnosis of spondylodiscitis.

Tubular Microdiscectomy for Recurrent Lumbar Disc Herniation: A Valuable Alternative to Endoscopic Techniques.

OBJECTIVE: The efficacy of tubular microdiscectomy (TMD) in the treatment of recurrent lumbar disc herniation (rLDH) is still unclear, especially compared with the endoscopic technique. We performed a retrospective study to analyze this question. METHODS: We retrospectively included all patients with an rLDH confirmed by magnetic resonance imaging who underwent TMD between January 2012 and February 2019. The general data included sex, age, body mass index, level of rLDH, first surgical approach, reoperation interval, occurrence of dural leak, re-recurrence, and re-reoperation. The clinical outcome was evaluated using a visual analog scale for leg pain, and the modified MacNab criteria were used to evaluate patient satisfaction. RESULTS: The visual analog scale score for leg pain was statistically significantly reduced from 7.46 preoperatively to 0.80 postoperatively (P < 0.00001), and the patient satisfaction was good or excellent in 85.7% of cases, according to the modified MacNab criteria. Complications occurred in 3 of the 15 included patients: 2 dural tears (13.3%) and 2 re-recurrence (13.3%), but none of the patients underwent a third surgical procedure. CONCLUSIONS: TMD seems to be an efficient technique for the surgical treatment of leg pain caused by rLDH. In the literature, this technique seems to be at least as good as the endoscopic technique and is easier to master.

Natural history and surgical outcome of incidentally discovered clinically nonfunctioning pituitary macroadenomas.

Objectives: The incidental diagnosis of nonfunctioning pituitary macroadenomas (NFPMAs) is becoming more prevalent with the spread of modern brain imaging techniques. We sought to uncover new data about their natural history and surgical outcome. Design: This is a retrospective single-center observational study. Methods: Among 210 patients seen for a NFPMA between 2010 and 2019, 70 (33%) were discovered incidentally (i-NFPMA). We analyzed outcomes in a total of 65 patients with available follow-up data. Results: Mean age at diagnosis (± s.d.) was 60 ± 14 years and mean maximal diameter was 20.0 ± 7.3 mm. At diagnosis, 29 patients (45%) had pituitary hormone deficits (LH/FSH 41%, TSH 29%, ACTH 15%) and 12% had visual field deficits. 26 patients underwent initial surgery, while 12 had delayed surgery after initial surveillance. In the surveillance group, the risk of tumor growth was estimated at 10%/year. Patients with hormonal deficits at diagnosis experienced earlier growth at 24 months (P < 0.02). Overall, surgical resection of the i-NFPMA led to stable or improved endocrine function in 91% of patients, with only 6% postoperative permanent diabetes insipidus. Moreover, surgery was more effective in preserving intact endocrine function (10/12) than restoring altered endocrine function to normal (6/22, P = 0.03). Conclusion: About one-third of NFPMAs are now discovered incidentally and a significant subset may be responsible for unrecognized endocrine and visual deficits. Under surveillance the risk of further tumor growth is significant (10%/year) and seems to occur faster in patients already harboring an endocrine deficit. Early surgical removal before onset of endocrine deficits appears to lead to better endocrine outcome.

Outcome of pituitary hormone deficits after surgical treatment of nonfunctioning pituitary macroadenomas.

OBJECTIVES: Nonfunctionning pituitary macroadenomas (NFPMA) are benign tumors that cause symptoms of mass effects including hypopituitarism. Their primary treatment is transsphenoidal surgery. We aimed to determine the outcome of pituitary hormone deficits after surgical treatment of NFPMA and to identify factors predicting hormonal recovery. DESIGN: We retrospectively included 246 patients with NFPMA diagnosed and operated in one of the two participating centers. All hormonal axes were evaluated except growth hormone (GH). Postoperative improvement of pituitary endocrine function was considered if at least one hormonal deficit had recovered and a lower total number of deficits was observed 1 year after surgery. RESULTS: 80% (n = 197) of patients had one or more pituitary deficits and 28% had complete anterior hypopituitarism. Besides GH, the gonadotropic and thyrotropic axes were the most commonly affected (68% and 62%, respectively). The number of hypopituitary patients dropped significantly to 61% at 1 year (p < 0.001) and a significant improvement was observed for all hormonal axes, except central diabetes insipidus. Among patients with preoperative hypopituitarism, 88/175 (50%) showed improved pituitary function at 1 year. Both hyperprolactinemia at diagnosis and a lower tumor diameter independently predicted favorable endocrine outcome. CONCLUSIONS: Hypopituitarism is present in 80% of patients with NFPMA and nearly half of them will benefit from sustained improvement after surgery. Hyperprolactinaemia at diagnosis and lower tumor dimensions are associated with favorable endocrine prognosis. This supports the option of early surgery in NFPMA patients with pituitary deficits independent of the presence of visual disturbances.

Long-term survival after glioblastoma resection: hope despite poor prognosis factors.

BACKGROUND: In spite of aggressive multimodal treatment, survival for patients with glioblastoma (GBM) remains short. Nevertheless, some patients survive much longer than expected and become long-term survival patients. The extent of resection (EoR), Karnofsky Performance Scale (KPS), age and methyl-guanine methyltransferase gene (MGMT) methylation are well-defined prognostic factors, but the characteristics of patients with long-term survival (LTS, survival of at least three years after diagnosis) has not been fully determined yet. That is the reason why we analyzed the GBM patients with LTS at our center. METHODS: We retrospectively reviewed all consecutive patients who underwent surgery for GBM between January 2002 and November 2011, including patients treated with surgical resection under neuronavigation with or without intraoperative MRI (ioMRI) and those who had stereotactic biopsy. We identified and further analyzed those patients with LTS. RESULTS: A total of 127 patients underwent surgery for GBM during the study period. 101 (79.6%) of whom had surgical resection and 26 (20.4%) of whom had stereotactic biopsy. Of the 101 patients who were treated with surgical resection, 12 had LTS. After two other pathologists reviewed the patients' cases, they confirmed that 11 (11%) of the 12 patients had a GBM (female/male ratio 4.5; average age 50 years; preoperative Karnofsky Score 82%), and one patient had an anaplastic glioma. The mean survival in the LTS patients with confirmed GBM was 74 (36-150) months. Seven of the LTS patients (63.6%) had a gross total resection (GTR), including two with an additional resection after ioMRI. Three (27.3%) had a near total resection (NTR: residue ≤5%) and one (9.1%) had a partial resection. Ten (90.9%) patients had a methylation of MGMT, only two (18.8%) had an IDH1 mutation, and seven (63.6%) received a full Stupp protocol. CONCLUSIONS: Among patients with a GBM who were treated with one or more resections, 11% had LTS with 90.9% with at least a near total resection (36% with ioMRI) and a methylated MGMT. 50% of the patients with a second surgery survived at least two years postoperatively. Those encouraging observations emphasize the importance of maximizing the resection by using, if possible, an intraoperative guidance method like ioMRI with an analysis of biomarkers such as MGMT and if necessary, multiple surgical procedures.

Long term outcome of anterior cervical discectomy and fusion using coral grafts.

BACKGROUND: To determine the long term efficacy of coral grafts in anterior cervical discectomy and fusion. METHODS: In this prospective longitudinal study, All patients presenting with myelopathy and/or radiculopathy due to discal hernia or cervical spondylosis underwent anterior cervical microdiscectomy, arthrodesis with coral, and stabilization with anterior cervical locking plates. Clinical and radiological post-operative evaluations were performed at 2 days, 3, 6, and 12 months, and then yearly. The visual analogue scale was used for the evaluation of pain. Fusion was defined as the absence of motion on dynamic imaging combined with the disappearance of radio-lucent lines around the graft. The mean follow-up period was 44 months. In 83.3%, 91.2% and 93.7% of patients there was a satisfactory outcome for neck pain, arm pain, and motor deficit, respectively. The overall complication rate was 17.5%, all of which were transient. Additional surgery was required in nine cases. The occurrence of complications is correlated with less satisfactory outcomes for both neck and arm pain. While 95.5% of patients expressed overall satisfaction with their surgery, 70.5% stated that they had returned to their previous activities. The fusion rate was 45%; which was not correlated with clinical outcome and more likely in patients with of cervical spondylosis and one-level arthrodesis. CONCLUSIONS: Despite satisfactory clinical results and a long follow-up period, coral implants yield low fusion rates, particularly in patients with discal hernia of two-level arthrodesis. The use of coral grafts cannot be recommended when fusion is one of the post-operative endpoints.

Comparative Cohort Study of Percutaneous Pedicle Screw Implantation without Versus with Navigation in Patients Undergoing Surgery for Degenerative Lumbar Disc Disease.

BACKGROUND: The major limitation of computer-based three-dimensional fluoroscopy is increased radiation exposure of patients and operating room staff. Combining spine navigation with intraoperative three-dimensional fluoroscopy (io3DF) can likely overcome this shortcoming, while increasing pedicle screw accuracy rate. We compared data from a cohort of patients undergoing lumbar percutaneous pedicle screw placement using io3DF alone or in combination with spine navigation. METHODS: This study consisted of 168 patients who underwent percutaneous pedicle screw implantation between 2009 and 2016. The primary endpoint was to compare pedicle screw accuracy between the 2 groups. Secondary endpoints were to compare radiation exposure of patients and operating room staff, duration of surgery, and postoperative complications. RESULTS: In group 1, 438 screws were placed without navigation guidance; in group 2, 276 screws were placed with spine navigation. Mean patient age in both groups was 58.6 ± 14.1 years. The final pedicle accuracy rate was 97.9% in group 1 and 99.6% in group 2. Average radiation dose per patient was significantly larger in group 1 (571.9 mGym2) than in group 2 (365.6 mGym2) (P = 0.000088). Surgery duration and complication rate were not significantly different between the 2 groups (P > 0.05). CONCLUSIONS: io3DF with spine navigation minimized radiation exposure of patients and operating room staff and provided an excellent percutaneous pedicle screw accuracy rate with no permanent complications compared with io3DF alone. This setup is recommended, especially for patients with a complex degenerative spine condition.

Outcome of Transsphenoidal Surgery for Cushing Disease: A Single-Center Experience over 20 Years.

BACKGROUND: This study investigated the outcome of transsphenoidal surgery (TSS) for Cushing disease (CD) and the influence of our surgical strategy on remission rates and postoperative pituitary function. PATIENTS AND METHODS: We retrospectively reviewed data from 71 patients with CD who underwent microscope navigation TSS (MN-TSS) in Saint-Luc Hospital between 1996 and 2017. True remission was defined as normal fasting cortisol level, normal 24-hour urinary free cortisol, or continued need for hydrocortisone replacement for 1 year after surgery. RESULTS: Overall remission rate after 1 or repeated MN-TSS was 83%. Highest remission rate was found in patients with macroadenomas (92%). Successful first MN-TSS was correlated with a high final remission rate (95%), whereas failed first MN-TSS was correlated with a low final remission rate (36%). Although day 1 cortisol levels were significantly lower in patients with long-term remission, high levels were still observed in a few patients, especially those who had had CD for many years. We found a low rate of postoperative pituitary long-term hypofunction (9.7%). CONCLUSIONS: MN-TSS is a safe and effective procedure to treat CD, allowing remission rates of 83%. One-year remission period after first surgery is correlated with a final remission rate of 95%. Although day 1 morning cortisol value is the most significant predictor for long-term remission, some patients with CD for many years may keep high postoperative cortisol levels and be in later remission, likely because of secondary adrenal hyperplasia. Our focused approach with microscope navigation resulted in low rates of postoperative pituitary hypofunction and kept a recurrence rate comparable to that in the literature.

Both invasiveness and proliferation criteria predict recurrence of non-functioning pituitary macroadenomas after surgery: a retrospective analysis of a monocentric cohort of 120 patients.

INTRODUCTION: Additional robust criteria to predict early postoperative recurrence of non-functioning pituitary macroadenomas (NFMAs) are needed. Recently, a new classification of pituitary tumors has been proposed, which is based on both radiological and histological criteria and allows the grading into 5 groups of different potential aggressiveness. The aim of this study was to use this classification to further characterize predictive factors of recurrence in an independent series of NFMA. CASES AND METHODS: 120 patients operated for a NFMA were analyzed retrospectively. For each of them, the invasion of the cavernous and/or sphenoidal sinuses by the tumor was studied on the preoperative MRI and the proliferative character was based on precise histological and immunohistological examination. RESULTS: 26% (n = 31) of the adenomas were proliferative and 57% (n = 68) were invasive. The invasive lesions were larger (P < 0.001) and their removal was complete in only 82% of the cases. The distribution of NFMAs was as follows: 32% grade 1a, 11% (proliferative) grade 1b, 42% (invasive) grade 2a and 15% (proliferative and invasive) grade 2b. Their probability of recurrence at 5 years was 20, 39, 44 and 66%, respectively. A young age, the atypical character and the presence of postoperative residual tumor were all independent risk factors of recurrence (P < 0.025). DISCUSSION: The new clinicopathological classification proves to be very useful in predicting the risk of recurrence of non-functioning pituitary macroadenomas after a first surgery. In particular, grade 2b lesions showed an overall likelihood of recurrence that was 8.6 times greater than those of grade 1a.

An Unusual Case of Ureteral Perforation in Minimally Invasive Pedicle Screw Instrumentation: Case Report and Review of the Literature.

BACKGROUND: Injury of the ureter is a potentially devastating complication most often reported in gynecologic, colorectal, or vascular pelvic surgery or endoscopic procedures for ureteric diseases. We report a rare case of ureteral rupture occurring as a complication of percutaneous pedicle screw placement. CASE DESCRIPTION: A 60-year-old man reported unbearable abdominal pain on the day after right L4-L5 transforaminal intervertebral fusion and percutaneous pedicle screw placement. A computer tomography workup showed contrast media extravasation outside the excretory system consistent with a left ureteral traumatic perforation. The patient underwent left nephrostomy and a double-J stent insertion and subsequently fully recovered. The ureter completely healed, enabling stent removal 5 months later. METHODS: PubMed and EMBASE were screened for ureteral injury caused by posterior lumbar surgery. RESULTS: We found 27 other reports with only 1 other case after minimally invasive transforaminal lumbar interbody. CONCLUSIONS: Complications of minimally invasive pedicle screw placement are often described as dural tear of neurologic impairment. This report shows that unexpected side effects are still possible and spine surgeons should be aware especially when performing minimally invasive procedures, in which, by definition, pedicles are concealed from direct visualization.

Pituitary stalk hemangioblastoma: the fourth case report and review of the literature.

Supratentorial hemangioblastomas (HBL) have been rarely described in the literature. Herein we report the fourth case of pituitary stalk HBL diagnosed concurrently with cerebellar HBLs in a 51-year-old woman with von Hippel-Lindau disease. Complete resection of the lesion was achieved using left frontopterional craniotomy and no recurrence was observed after 8 years of follow-up. The clinical presentation, radiological features, pathological findings, and the management of this particular case are discussed in the light of the available literature. To our knowledge, this case is the only pituitary stalk HBL with total resection, and a long follow-up fully documented.

Spine Navigation Based on 3-Dimensional Robotic Fluoroscopy for Accurate Percutaneous Pedicle Screw Placement: A Prospective Study of 66 Consecutive Cases.

BACKGROUND: Minimally invasive spine surgery is associated with obstructed visibility of anatomic landmarks and increased radiation exposure, leading to higher incidence of pedicle screw mispositioning. To address these drawbacks, intraoperative 3-dimensional fluoroscopy (io3DF) and navigation are being increasingly used. We aimed to present our dedicated multifunctional hybrid operating room (HyOR) setup and evaluate the accuracy and safety of io3DF image-guided spinal navigation in transforaminal lumbar interbody fusion with percutaneous pedicle screw (PPS) placement. METHODS: The HyOR includes a fixed 3D multiaxis robotic fluoroscopy arm that moves automatically to the preprogrammed position when needed. An initial io3DF assessment is performed to collect intraoperative images, which are automatically transferred into the navigation system. These data are used to calibrate the PPSs and insert them under computer-assisted navigation. A second io3DF is performed for verifying PPS position. RESULTS: Between January 2014 and December 2016, 66 consecutive patients (age, 58.6 ± 14.1 years) were treated for refractory lumbar degenerative pain. Seventy-three spinal levels were treated, and 276 screws were placed, with 4.2 ± 0.76 screws per patient. There was no measurable radiation to the HyOR staff, whereas the mean radiation dose per patient was 378.3 µGym2. The overall accuracy rate of PPS placement was 99.6%. There were no significant procedure-related complications. CONCLUSIONS: Spine navigation based on io3DF images enabled us to avoid radiation exposure to the operating room team while delivering minimal but sufficient radiation doses to our patients. This approach achieved an accuracy rate of 99.6% for PPS placement in the safe zone, without significant complications.

Unusual association between lysinuric protein intolerance and moyamoya vasculopathy.

INTRODUCTION: Lysinuric protein intolerance (LPI) is a form of inherited aminoaciduria caused by a deficiency in the cationic amino acid transport process on the basolateral membrane of enterocytes and renal tubular cells. Clinical signs include gastrointestinal symptoms, failure to thrive, hepatosplenomegaly, osteoporosis, episodes of coma, intellectual deficiency, lung and renal involvement, bone marrow abnormalities, as well as altered immune response. Moyamoya disease is a cerebrovascular disorder predisposing sufferers to stroke through progressive stenosis of the intracranial internal carotid arteries and their proximal branches. Patients with characteristic moyamoya vasculopathy who also exhibit well-recognized associated conditions, such as Down syndrome or sickle-cell disease, are diagnosed with moyamoya syndrome, whereas those with no known associated risk factors are said to suffer from moyamoya disease. CASE STUDY: A 5-year-old girl exhibiting aversion to protein-rich food and splenomegaly presented with a history of recurrent ischemic strokes. Cerebral angiography confirmed moyamoya vasculopathy. Metabolic investigation revealed abnormalities characteristic of LPI. This diagnosis was confirmed by the detection of a mutation within the SLC7A7 gene upon molecular investigation. CONCLUSION: To the best of our knowledge, this is the first reported case of an association between moyamoya vasculopathy and LPI. While the question of association or coincidence cannot yet be answered, several pathophysiological consequences of LPI can be defined as separate, such as links between the impact of low arginine levels on the function of vascular endothelium and brain nitric oxide metabolism, as well as hemophagocytic syndrome associated with the risk of vasculitis, thus accounting for the development of moyamoya vasculopathy.

Intraoperative 3T MRI for pituitary macroadenoma resection: Initial experience in 73 consecutive patients.

OBJECTIVE: To report a single-center experience with a 3T intraoperative magnetic resonance imaging (iMRI) to assess transsphenoidal microsurgery on pituitary macroadenomas. METHODS: In a dual, independent operating room (OR) magnetic resonance imaging (MRI) suite, the operating table with the anesthetized patient was moved on rail tracks once a supposed maximized resection was reached to the MRI room for intraoperative image acquisition and interpretation. After the assessment of the iMRI images, the neurosurgeon evaluated whether additional resection was still possible. The resection rates were assessed on iMRI and postoperative MRI at 3 months. RESULTS: A total of 73 macroadenomas benefited from an iMRI from March 2006 to October 2011. The gross total resection (GTR) rate at the time of the first iMRI was 58.9% (n=43). Based on the iMRI, eight patients (10.9%) underwent a second surgical resection. In 3 cases, the intraoperative imaging results were suspicious for a minor residue but not convincing enough for further surgery. Fortunately, the 3 months postoperative MRI control did not disclose any residual tumor in these cases. Finally, the GTR rate at the 3-month postoperative MRI increased to 72.6% (n=53). CONCLUSIONS: 3T intraoperative MRI offered excellent quality images. Its use during transsphenoidal microsurgery on pituitary macroadenomas led to an increase not only in the extent of tumor resection (in 8 patients) but also in the rate of radical resections (69% instead of 60%). No complications due to the iMRI procedure were observed.

Outcome of transsphenoidal surgery for Cushing's disease: a high remission rate in ACTH-secreting macroadenomas.

OBJECTIVE: Although numerous studies have shown that transsphenoidal surgery is the best initial treatment for Cushing disease offering 59-95% of success, fewer information is available on the long-term outcome in the subgroup of patients harboring ACTH-secreting macroadenomas. The aims of this study were to analyze our 10-year experience with transsphenoidal surgery in Cushing's disease and to examine whether remission rates were different between micro- and macroadenomas. PATIENTS AND METHODS: Forty consecutive patients with proven Cushing's disease (28 microadenomas, 12 macroadenomas [diameter: 10-25 mm], 3 patients with no visible adenoma at MRI) underwent transsphenoidal surgery (TSS) assisted by neuronavigation in our center between 1996 and 2007. The diagnosis was made using standard endocrinological criteria including bilateral inferior petrosal sinus sampling (BIPSS) with CRH stimulation in all patients with discordant or equivocal biochemical and radiological testing. Morning serum cortisol was measured during the first week postoperatively, and a complete endocrine evaluation was made in all patients at 6-8 weeks. Remission at follow-up was defined as a normal postoperative 24-h urinary free cortisol (UFC) or continued need for glucocorticoid hormone replacement after TSS. RESULTS: Overall, 32/40 patients (80%) were in remission after one or more TSS. Interestingly, a very good remission rate (92%) was observed in the subset of macroadenomas, similar to that found in the group of microadenomas (84%, NS), while no post-surgical remission was observed in the 3 patients with no visible adenoma at MRI (p<0.01). Of the 8 patients not in remission after repeated TSS surgery, 3 underwent radiation therapy and three had bilateral adrenalectomy, allowing remission of their hypercortisolism. There was minor morbidity and no death. CONCLUSION: While our overall results are in accordance with other published series, we show here that ACTH-secreting pituitary macroadenomas are usually not associated with a bad outcome, in contrast with patients with no visible adenoma at preoperative MRI.

Refractory High Intracranial Pressure following Intraventricular Hemorrhage due to Moyamoya Disease in a Pregnant Caucasian Woman.

Intraventricular hemorrhage during pregnancy is usually followed by a poor recovery. When caused by moyamoya disease, ischemic or hemorrhagic episodes may complicate the management of high intracranial pressure. A 26-year-old Caucasian woman presented with generalized seizures and a Glasgow Coma Score (GCS) of 3 during the 36th week of pregnancy. The fetus was delivered by caesarean section. The brain CT in the mother revealed bilateral intraventricular hemorrhage, a callosal hematoma, hydrocephalus and right frontal ischemia. Refractory high intracranial pressure developed and required bilateral ventricular drainage and intensive care treatment with barbiturates and hypothermia. Magnetic resonance imaging and cerebral angiography revealed a moyamoya syndrome with rupture of the abnormal collateral vascular network as the cause of the hemorrhage. Intracranial pressure could only be controlled after the surgical removal of the clots after a large opening of the right ventricle. Despite an initially low GCS, this patient made a good functional recovery at one year follow-up. Management of refractory high intracranial pressure following moyamoya related intraventricular bleeding should require optimal removal of ventricular clots and appropriate control of cerebral hemodynamics to avoid ischemic or hemorrhagic complications.

Quantitative assessment of anaesthetic nerve block and neurotomy in spastic equinus foot: a review of two cases.

OBJECTIVE: To quantitatively evaluate the effect of motor nerve branch block and neurotomy of the soleus nerve on triceps surae spasticity, reviewing 2 cases. METHODS: Beside clinical assessment, we carried out a quantitative measurement of the stiffness of the ankle flexor muscles. The path length of the phase diagram between elastic and viscous stiffness quantifies the reflex response to movement and reflects the importance of the spasticity. The assessments were carried out before and 30 min after motor nerve branch block of the upper soleus nerve and more than 7 months after neurotomy. RESULTS: Both patients presented with pronounced ankle plantar flexor spasticity: their path lengths were more than 6 times greater than normal values at baseline (#1: 354 N m rad(-1); #2: 409 N m rad(-1)). Motor nerve branch block and neurotomy allowed a near-normalization of elastic and viscous stiffness of ankle plantar flexor muscles in the 2 patients. Their path length was almost similarly improved by motor nerve branch block (#1: 127 N m rad(-1); #2: 231 N m rad(-1)) and neurotomy (#1: 60 N m rad(-1); #2: 162 N m rad(-1)). CONCLUSION: These case reports highlight the fundamental role of the soleus muscle in triceps surae spasticity in our patients, the predictivity of motor nerve branch block in the preoperative assessment, and the effectiveness of soleus neurotomy in spastic equinus foot.