Secondary outcomes of scoliosis surgery in disease-modifying treatment-naïve patients with spinal muscular atrophy type 2 and nonambulant type 3.

INTRODUCTION/AIMS: Available studies on scoliosis surgery in spinal muscular atrophy (SMA) have focused on the primary outcome of the procedure-the correction of the curve-whereas research focusing on secondary outcomes is scarce. We aimed to investigate postsurgical changes in respiratory function, motor function, weight, pain, and satisfaction. METHODS: We retrospectively reviewed the clinical notes of 32 disease-modifying treatment-naïve patients (26 SMA2, 6 nonambulant SMA3). We also performed investigator-developed phone interviews and conducted a focus group with families on postsurgical satisfaction. RESULTS: Mean annual rate of forced vital capacity percent decline improved in SMA2: -3.2% postsurgery versus -6.9% presurgery (p < .001), with similar trajectories in SMA3. Gross motor functional scores (Hammersmith Functional Motor Scale) available in 12/32 dropped immediately after surgery: median loss of 6.5 points, with relatively spared upper limb function. Weight z-scores postsurgery dropped in 16/32, requiring food supplements (5/16); one/16 lost >5% of total weight requiring gastrostomy. Postsurgical pain was frequently reported, especially hip pain (13/32). Overall, 10/10 patients/parents participating in the phone interview rated the procedure as very successful for posture and physical appearance. Nonetheless, 7/10 reported postsurgical pain, reduced mobility, and unmet care needs. The seven patients/parents attending the focus group highlighted lack of intensive physiotherapy programs, occupational therapy assistance, and psychological support as postsurgical unmet care needs. DISCUSSION: This study reports a positive impact of scoliosis surgery on respiratory function and overall satisfaction with posture and physical appearance. The observed negative impact on the other outcomes highlights the importance of multidisciplinary approaches to improve postoperative management.

Anterior cervical discectomy and fusion for the treatment of pediatric Hirayama disease.

PURPOSE: Hirayama disease, a rare cervical myelopathy in children and young adults, leads to progressive upper limb weakness and muscle loss. Non-invasive external cervical orthosis has been shown to prevent further neurologic decline; however, this treatment modality has not been successful at restoring neurologic and motor function, especially in long standing cases with significant weakness. The pathophysiology remains not entirely understood, complicating standardized operative guidelines; however, some studies report favorable outcomes with internal fixation. We report a successful surgically treated case of pediatric Hirayama disease, supplemented by a systematic review and collation of reported cases in the literature. METHODS: A review of the literature was performed by searching PubMed, Embase, and Web of Science. Full-length articles were included if they reported clinical data regarding the treatment of at least one patient with Hirayama disease and the neurologic outcome of that treatment. Articles were excluded if they did not provide information on treatment outcomes, were abstract-only publications, or were published in languages other than English. RESULTS: Of the fifteen articles reviewed, 63 patients were described, with 59 undergoing surgery. This encompassed both anterior and posterior spinal procedures and 1 hand tendon transfer. Fifty-five patients, including one from our institution, showed improvement post-treatment. Eleven of these patients were under 18 years old. CONCLUSION: Hirayama disease is an infrequent yet impactful cervical myelopathy with limited high-quality evidence available for optimal treatment. The current literature supports surgical decompression and stabilization as promising interventions. However, comprehensive research is crucial for evolving diagnosis and treatment paradigms.

Laminoplasty with tented duraplasty for Hirayama disease.

BACKGROUND: Hirayama disease (HD) is a characterized by progressive amyotrophy of the upper limbs due to a forward displacement of the cervical dura during neck flexion. METHODS: Unlike other treatment options aiming at preventing cervical flexion (e.g., collar or arthrodesis), laminoplasty with tented duraplasty addresses dural dysplasia. Technically, the procedure consists in enlarging the dural sac by performing an expansile duraplasty that is secured to the yellow ligaments, in association with an open-book laminoplasty. CONCLUSION: Laminoplasty with tented duraplasty is a surgical option addressing the cause of HD to prevent further neurological deterioration while preserving cervical motion.

Impact of Spinal Surgery on Intrathecal Nusinersen Injections in Pediatric Spinal Muscular Atrophy.

BACKGROUND: Complex spinal deformities necessitate surgical interventions that may intervene with intrathecal injections in patients with spinal muscular atrophy (SMA). This study aimed to determine the effect of spinal deformity correction surgery on nusinersen administration. METHODS: Pediatric patients with SMA, operated by a single surgeon, either via magnetically controlled growing rod (MCGR) or definitive fusion (DF) with skip instrumentation, were evaluated retrospectively in terms of safety and feasibility of intrathecal injections. Patients' and their parents' perspectives were evaluated through a questionnaire regarding any shift in the setting of injections. RESULTS: Fourteen patients with 15 spinal surgeries (10 MCGR and 5 DF) were included. Eleven patients received intrathecal treatment both before and after the surgery. Preoperative (n=3) and postoperative (n=9) fluoroscopic guidance was required leading to a shift in the application settings in 6 patients. Of 106 preoperative injections, 15% required fluoroscopy and 2% required anesthesia. Postoperatively, of 88 injections, 73% required fluoroscopy and 26% required anesthesia. No patients discontinued intrathecal injections due to technical difficulties associated with the spinal surgery. CONCLUSIONS: This study demonstrates that spinal surgery does not prevent safe and successful intrathecal nusinersen injections. In the DF group, the skip instrumentation technique provided access to interlaminal space for intrathecal injections. In either surgical group, no further auxillary approach was required. Modifications in the injection technique require an institutional approach, and concerns of patients and their families should be addressed accordingly. LEVEL OF EVIDENCE: IV.

Procedural sedation for paediatric patients with spinal muscular atrophy undergoing intrathecal treatment.

AIMS: Nusinersen is administered intrathecally for treating spinal muscular atrophy (SMA). Procedural sedation is common with intrathecal treatment in children. The purpose of this study is to emphasize that intrathecal treatment of paediatric patients with SMA I, II and III can be tolerated with procedural sedation instead of general anaesthesia. METHODS: Data were collected the from the anaesthesia charts and electronic medical records of 14 paediatric patients with SMA types I, II and III who underwent procedural sedation for repeated intrathecal treatments for SMA. Intravenous induction was performed, and patients were oxygenated with a face mask or nasal cannula while spontaneous breathing continued. RESULTS: Fourteen patients were included in the study: one SMA I, eight SMA II and five SMA III. They underwent 88 intrathecal nusinersen injections in total. In the one SMA I patient, of 8 months, the procedure was performed under local anaesthesia. In all other patients, the treatments were performed under procedural sedation. Different combinations of midazolam, ketamine, propofol, fentanyl and remifentanil were used. The mean doses of the agents used were 0.03 mg kg-1 , 0.97 mg kg-1 , 2.71 mg kg-1 , 0.84 µg kg-1 and 0.5 µg kg-1 , respectively. There were no intraoperative or postoperative complications. CONCLUSION: We found the procedural sedation to be sufficient, safe and effective in SMA II and III paediatric patients who underwent nusinersen treatment intrathecally, provided anaesthetic agents are titrated and administered carefully.

Outcome of Tendon Transfer for Monomelic Amyotrophy (Hirayama Disease).

Hirayama disease is a motor neuron disease predominantly affecting adolescent males. The identifying feature of Hirayama disease is unilateral forearm and intrinsic muscle weakness that spares the brachioradialis, termed "oblique atrophy." Hirayama disease progresses slowly over several years, followed by an abrupt arrest. The pathognomonic finding is the anterior displacement of the cervical spinal cord with the detachment of the posterior dura. Systematic clinical evaluation and appropriate diagnostic studies are crucial to rule out a variety of compressive, immune-mediated, and genetic disorders. We present a patient with Hirayama disease whose hand function was improved dramatically by a tendon transfer after nearly 3 years without a definitive diagnosis and call attention to the hand surgeon's role in identifying this rare disease to enable timely functional restoration.

Spinal Muscular Atrophy Type III Recognized After Delayed Recovery From Neuromuscular Blockade After an Orthognathic Surgery.

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by the degeneration of alpha motor neurons in the spinal cord, resulting in progressive proximal muscle weakness and paralysis. SMA is classified into types I-IV based on the age at symptom onset or maximum motor function achieved, and its clinical manifestations vary. SMA affects maxillofacial growth because of muscle dysfunction and results in abnormal maxillofacial morphology. In addition, definitive diagnosis is not often made because of the older onset age and symptoms are rarely severe. Therefore, the possibility of undiagnosed SMA in craniofacial surgeries must be considered. This report described a case of an SMA type III recognized after delayed recovery from the neuromuscular blockade in an orthognathic surgery under general anesthesia.

Impact of various cervical surgical interventions in patients with Hirayama's disease-a narrative review and meta-analysis.

Hirayama disease (HD) is a relatively uncommon cause of lower cervical myelopathy. A number of surgical approaches have been described in patients with HD in literature. We reviewed the literature and did a systematic review and meta-analysis of the studies which presented the clinical outcome following surgical intervention in HD. A systematic search of literature was performed with the keywords "Surgical treatment in Hirayama Disease", "Surgical approach in Hirayama Disease" and "Hirayama disease surgery". Data related to clinical outcome following surgery was pooled to calculate the pooled proportion of clinical improvement following anterior and posterior surgical approach. Thirty-four articles met the inclusion criteria and were included in the final review. Altogether, there were 10 types of surgical procedures performed for Hirayama disease. The most commonly described surgical technique was anterior cervical discectomy and fusion with cervical plating. The pooled proportion of patients experiencing clinical improvement following all cervical approaches was 80% (95% confidence interval 76 to 84%). Pooled proportion was maximum for anterior cervical plating (96% (95% confidence interval 62 to 100%)) and minimum for ACDF without plating (57% (95% confidence interval 20 to 88%)). Subgroup analysis based on different surgical approaches was not significant (p value = 0.61). The pooled proportion of patients experiencing clinical improvement following anterior and posterior cervical approach was 80% (95% confidence interval 76 to 84%) and 81% (95% confidence interval 66 to 91%). The indications of surgical treatment in patients with HD include poor patient compliance for neck collar or rapidly progressing severe disease. Good results with more than 80% chances of clinical improvement have been reported following various anterior and posterior surgical approaches. However, there was no significant difference in the pooled outcome of different surgical approaches. Most common technique used in literature is anterior cervical discectomy and fusion with plating.

Hirayama Disease in a Patient with a History of Late-Onset Symptomatic Vein of Galen Aneurysmal Malformation.

INTRODUCTION: The purpose of this report is to present a rare case of Hirayama disease (HD) in a patient with a history of late-onset symptomatic vein of Galen aneurysmal malformation (VGAM). This report may provide new insights into the pathophysiology of HD, a rare disorder consisting of insidious onset of unilateral weakness and atrophy of the forearm and intrinsic hand muscles. These symptoms are believed to result from cervical myelopathy affecting the anterior horn cells due to abnormal compressive forces on the spinal cord from adjacent anatomical structures (i.e., dura and/or epidural veins), but this has not been proven. VGAM is a rare congenital cerebral vascular malformation, consisting of high-flow arteriovenous shunting between a persistent median prosencephalic vein and arterial feeders, which most frequently presents in the early neonatal period with congestive heart failure. CASE PRESENTATION: We report the case of an otherwise healthy boy who presented with heart failure due to VGAM at 7 years and subsequently presented at 14 years with left-sided HD. His cervical MRI with neck flexion revealed enlarged epidural veins at the C5-C6 spinal level with anterior, leftward displacement of the posterior dura and spinal cord as well as left hemicord flattening and/or atrophy at this level. He underwent successful surgical treatment by C5-C6-C7 osteoplastic laminotomies and tenting and expansile autologous duraplasty, during which enlarged, engorged epidural veins were confirmed and coagulated. This halted the progression of his left hand weakness and atrophy and allowed significant functional improvement. Postoperative catheter angiogram showed no anatomical connection between the persistent VGAM and the engorged epidural veins, and genetic testing revealed no genetic predisposition of vascular malformations. DISCUSSION/CONCLUSION: In this patient, a combined surgical technique was performed that included epidural venous plexus coagulation with posterior autologous duraplasty and dural fixation using tenting sutures. This combined approach led to a favorable clinical and radiographic outcome with no complications or limitations and has not been previously proposed in the literature, to our knowledge. Although not completely ruled out, we found no angiographic connection or genetic predisposition to suggest there is a pathophysiological link between HD and VGAM.

Improvement of Pulmonary Function Measured by Patient-reported Outcomes in Patients With Spinal Muscular Atrophy After Growth-friendly Instrumentation.

BACKGROUND: Children with spinal muscular atrophy (SMA) sustain a progressive reduction in pulmonary function (PF) related to both muscular weakness and the concomitant effects of spinal deformity on the thorax. Growth-friendly instrumentation is commonly utilized for younger patients with scoliosis and SMA to halt the progression of spinal curvature, but its effect on PF in these patients has not previously been investigated. Using the change in Early Onset Scoliosis 24-Item Questionnaire (EOSQ-24) PF subdomain scores, the authors will investigate whether PF improves in patients with SMA after a growth-friendly intervention. METHODS: This was a multicenter retrospective cohort study from 2 international registries of patients with SMA undergoing spinal deformity surgery from 2005 to 2015. Data collected were age, sex, degree of major coronal curve, type of growth-friendly construct, forced vital capacity (FVC), and EOSQ-24 scores at the patient's preoperative, 1-year postoperative, and 2-year postoperative visits. Differences in EOSQ-24 PF scores and FVC between baseline and postoperative assessment were examined by paired tests. RESULTS: A total of 74 patients were identified (mean age, 7.6±2.3 y, major curve 68.1±22.4 degrees, 51.4% female individuals). The mean EOSQ-24 PF scores improved significantly from 70.6 preoperatively to 83.6 at 1 year (P=0.092) and 86.5 at 2 years postoperatively (P=0.020). The scores in patients with rib-based constructs showed steeper increases at 1-year assessments than those in patients with spine-based constructs. The mean paired FVC value decreased from 63.9% predicted preoperatively, to 57.6% predicted at 1 year postoperatively (P=0.035), and 61.9% predicted preoperatively, to 56.3% predicted at 2 years postoperatively (P=0.178). CONCLUSIONS: Patients with SMA who received growth-friendly instrumentation did experience improvements in PF as measured by EOSQ-24 assessing the caregivers' perception. Given the uncertain reliability of PFTs in this young population, EOSQ-24 is an important tool for measuring improvements in health-related quality of life. LEVEL OF EVIDENCE: Level III-retrospective study.

Early Results of a Management Algorithm for Collapsing Spine Deformity in Young Children (Below 10-Year Old) With Spinal Muscular Atrophy Type II.

BACKGROUND: Progressive C-shaped scoliosis with marked pelvic obliquity is common to spinal muscular atrophy (SMA). Reducing the number of procedures with effective deformity control is critical to minimize the risk of pulmonary complications. This study reports the preliminary results of magnetically controlled growing rods (MCGR) in SMA-related collapsing spine deformity. METHODS: Inclusion criteria for this retrospective review were: (1) SMA type 2 patients, (2) early onset scoliosis (below 10 y), (3) collapsing spine deformity with pelvic obliquity, (4) growth-friendly scoliosis treatment with MCGR, (5) in between 2014 and 2017. Extracted data included demographic and clinical information, radiologic parameters, surgical details, and final status of the patients. RESULTS: A total of 11 patients (7 boys, 4 girls) were included. The average age at index surgery was 8.2 (6 to 10) years. Dual MCGR was implanted in 8 patients. In 3 patients, because of curve rigidity and inability of apex to be brought into the stable zone, apical fusion with gliding connectors (convexity) and a single MCGR (concavity) was preferred. Instrumentation included the pelvis in 9 and stopped at the lumbar spine (L3) in 2 patients at the index procedure. Average preoperative deformity of 81.8 degrees (66 to 115) decreased to 29 degrees (11 to 57) postoperatively and was 26 degrees at average 35 months (16 to 59). Pelvic obliquity of 20.9 degrees (11 to 30) decreased to 4.9 degrees (2 to 8) after index surgery and was 6.5 degrees (2 to 16) at the last follow-up. T1-S1 height of 329 mm (280 to 376) after index surgery increased to 356 mm (312 to 390) after 9.2 (4 to 20) outpatient lengthening. No neurologic, infectious, or implant-related complication was recorded. Distal adding-on deformity occurred in 2 patients without initial pelvic fixation.One patient deceased secondary to pneumonia at 16 months after surgery. CONCLUSIONS: Short-term results indicate that MCGR may be a good option in SMA-associated collapsing spine deformity to reduce the burden of repetitive lengthening procedures. The authors recommend apical deformity control in the convex side in case of curve rigidity. In addition, including the pelvis in the instrumentation at index surgery is critical to prevent distal adding-on. LEVEL OF EVIDENCE: Level IV-retrospective case series.

VEPTR: Are We Reducing Respiratory Assistance Requirements?

BACKGROUND: The assisted ventilation rating (AVR) indicates the degree of external respiratory support required in children with thoracic insufficiency syndrome (TIS) and early onset scoliosis. For skeletally immature patients with TIS, the vertical expandable prosthetic titanium rib (VEPTR) device can be used to improve lung volume and growth. We hypothesized that patients who underwent early thoracic reconstruction by VEPTR treatment had an improved respiratory status. METHODS: Preoperative and postoperative AVR ratings were prospectively collected in a multicenter study group and compared to determine change after VEPTR treatment. Patients under 10 years of age at initial implant with minimum of 2-year follow-up data were included. Patients were excluded if there were incomplete data or if initial AVR was normal (breathing on room air). Statistical analysis was performed on groups which had stable, declined, and improved AVR at final follow-up. RESULTS: Database search yielded 77 patients with initial abnormal AVR. Average follow-up was 5.6 years. The most frequent primary diagnoses were congenital scoliosis (n=14) and spinal muscular atrophy (n=14). In total, 19 (24%) demonstrated improvement, 9 (12%) patients deteriorated, and 49 (64%) remained at the same level. The average preoperative major curve in those with improvement (58.4 degrees) and those with no change (63.5 degrees) was less than in those with deterioration (85.5 degrees) (P=0.014). The average age in years at implant of those with improvement (4) was less than those declined (6.7) and those with no change (5.5). In total, 16 (84.2%) of those that improved had a normal AVR and did not require respiratory support at last follow-up. CONCLUSIONS: There is evidence that a subset of patients with early onset scoliosis and TIS who received early thoracic reconstruction with VEPTR treatment show complete resolution of pulmonary support at final follow-up. In total, 89% of 79 patients did not experience respiratory deterioration. A total of 24% (n=19) had a positive change with over 84% (n=16) of this group no longer requiring support. LEVEL OF EVIDENCE: Level III-prognostic.

[Midterm clinical outcomes and radiological results of surgical treatment for Hirayama disease].

OBJECTIVE: To assess the midterm clinical and radiological outcomes of internal fixation and fusion for the treatment of Hirayama disease and to evaluate the clinical significance and value of this procedure. METHODS: In the study, 36 patients were treated with anterior cervical internal fixation and fusion. The clinical outcomes including muscle strength and atrophy were recorded. The radiological outcomes including range of motion of cervical spine and the cross-sectional area of spinal cord at each level on MRI scan were measured before and at 3 month, 1 year and 2 years follow-up time points after surgery. RESULTS: (1) Clinical outcomes: all the patients showed no further progression of symptoms except one patient with mild progression of muscular weakness and atrophy. As the time passed by, the ratio of the patients with muscle strength and atrophy improvement increased. There were 26.5% of patients in 3 months, 36.0% in 1 year and 85.7% in 2 years who experienced muscle strength improvement. 8.8% of patients in 3 months, 24.0% in 1 year and 35.8% in 2 years felt muscle atrophy improvement. And 12 of the 14 patients showed improved muscle strength and atrophy at the end of 2 years period follow-up. (2) Radiological outcomes: the range of motion (ROM) of C2-C7 was significantly decreased after the operation. The ROM of preoperation was 62.25°±2.10° and that of 2 years postoperation was 13.67°±7.51°(P<0.01). The spinal cord was of no compression on flexion MRI. The cross-section area of spinal cord on MRI was significantly increased only at C6 level (P<0.05) at the end of three months follow-up. The level of increased cross-section area rose to C4-C5-C6 levels (P<0.01) in 1 year and to C4-C5-C6-C7 levels at the end of 2 years follow-up (P<0.05). The cross-section area increased 15.60% at C4, 19.08% at C5, 21.60% at C6 and 23.91% at C7 with significant difference (P<0.05) 2 years after the operation. CONCLUSION: Anterior cervical internal fixation and fusion is an effective surgical treatment for Hirayama disease and may provide preferable midterm clinical and radiological outcomes. This procedure has clinical significance and value in terms of control of the progression and outcome of this disease.

Self-growing Instrumentation With Gliding Connectors for Collapsing Spine Deformities in Children: A Novel Technique.

BACKGROUND: The optimal management of young children with neuromuscular spinal deformities is currently unknown. A number of spinal instrumentation techniques have been proposed in early-onset scoliosis to achieve "guided growth," each with its drawbacks. OBJECTIVE: To report a novel self-growing spinal instrumentation technique, designed to avoid recurrent surgeries in children with neuromuscular disease. METHODS: The technique is based on the control of apical and end vertebrae by pedicle screw fixation and limited fusion. Standard 4.5 to 5.5 mm side-to-side rod connectors are used as gliding connections. Three children with neuromuscular disease underwent the described procedure. The patients were followed for an average of 36 months (range, 24 to 60 mo). RESULTS: All patients who underwent the procedure showed an average spinal growth of 1.1 mm/year, which is comparable with normative growth data and previous reports using growing rods. One patient required the exchange of dislodged rods, secondary to the amount of growth of the spine. There were no other complications or unplanned surgeries during the follow-up period. CONCLUSIONS: This novel method provided growth in a group of 3 patients with collapsing neuromuscular spine deformities. LEVEL OF EVIDENCE: Level IV-case series.

Hirayama disease: Is surgery an option?

INTRODUCTION: Hirayama disease is a rare cervical myelopathy, predominantly affecting young males, which presents with distal atrophy of the upper limbs as its first and main symptom. It must be differentiated from motor neuron diseases because its natural history is different and because HD tends to stabilise in less than 5 years. Diagnosis is based on clinical findings and dynamic flexion MRI showing segmental spinal muscular atrophy, detachment of the posterior dura mater and venous congestion in the epidural space. The tendency is to indicate conservative treatment and no indications for surgery have been established. PATIENTS: We present 4 cases meeting both clinical criteria and dynamic MRI imaging criteria for a diagnosis of Hirayama disease. Two have stabilised spontaneously over the course of many years, and MRI scans show that typical changes have disappeared. Another case also remains stable following a shorter observation time. The fourth case is a young man who developed severe myelopathy in just over a year, and therefore underwent surgery. While his follow-up time is still short, his condition remains stable. CONCLUSIONS: Our 4 cases suggest that the condition of most patients with Hirayama stabilises naturally; patients should be evaluated for surgery on an individual basis, and surgery should probably be limited to the most severe cases that have progressed quickly.

[A clinical study of laryngotracheal separation in spinal muscular atrophy type I patients].

Artificial respiration by tracheostomy is necessary for long-term survival in spinal muscular atrophy (SMA) Type I patients. There are two types of tracheostomy: i )simple tracheostomy and ii) tracheostomy plus aspiration prevention surgery, including laryngotracheal separation. We experienced three cases of SMA type I patients that had good outcomes after undergoing laryngotracheal separation. The patients' ages at onset were 14 days, two months and one and a half months. Laryngotracheal separation was performed at five months, seven months, and 15 years and five months respectively, and the times from diagnosis to surgery were a month, three months and 15 years. The aspiration pneumonia disappeared in all three cases. This study suggests that laryngotracheal separation is an effective surgery to prevent aspiration in SMA type I cases, and also contributes to the improved quality of life of patients and their families.

Multilevel anterior cervical discectomy and fusion with plate fixation for juvenile unilateral muscular atrophy of the distal upper extremity accompanied by cervical kyphosis.

STUDY DESIGN: A retrospective clinical study was conducted and related literatures were reviewed. OBJECT: This study aimed to evaluate outcome of multilevel anterior cervical discectomy and fusion with plate fixation for juvenile unilateral muscular atrophy of the distal upper extremity accompanied by cervical kyphosis. SUMMARY OF BACKGROUND DATA: Juvenile unilateral muscular atrophy of the distal upper extremity is a rare disease. Traditional treatment uses a neck collar to immobilize neck motion. However, if the disease is accompanied by cervical kyphosis, conservative treatment is difficult to correct cervical kyphosis and the prognosis is worsened. Therefore, it is important to initially apply surgical treatment for juvenile unilateral muscular atrophy accompanied with cervical kyphosis. METHODS: From March 2008 to May 2010, 4 patients were transferred to our spine medical center because of a history of slowly progressive distal weakness and atrophy of their hands and forearms. Four patients were diagnosed with Hirayama disease accompanied with cervical kyphosis based on their clinical representations and radiologic findings. After conservative treatment failed, these patients underwent multilevel anterior cervical discectomy and fusion with plate fixation. The clinical outcomes were retrospectively evaluated with follow-up ranging from 1.5 to 3 years. RESULTS: The clinical and radiologic follow-up indicated satisfactory clinical relief from symptoms, cervical sagittal alignment and cervical spinal canal volume, for all the patients. Within 6 months after surgery, the JOA score improved from a preoperative average of 14 to a postoperative average of 16.3; JOA recovery rates of all patients were more than good level. The muscle strengths of intrinsic muscles, wrist flexors and extensors, and biceps and triceps muscle improved on average by 1 grade. No complications occurred. CONCLUSIONS: Hirayama disease is a rare disease, a proper diagnosis of which can be made based on significant clinical symptoms and neurological imaging (dynamic MRI). The primary results from this study showed the tendency that multilevel anterior cervical discectomy and fusion with plate fixation is a preferred treatment for patients showing anterior effacement and apparent cervical kyphosis.

Monomelic Amyotrophy/Hirayama Disease: Surgical Outcome in a Large Cohort of Indian Patients.

BACKGROUND: Hirayama disease (HD) is a cervical compressive myelopathy. Anterior cervical discectomy and fusion (ACDF) is identified as the best surgical approach. We evaluated surgical outcomes and factors influencing ACDF in HD. METHODS: Between 2015 and 2019, 126 patients with HD underwent ACDF. Contrast magnetic resonance imaging of the cervical spine in full flexion was performed. Clinical examination and preoperative/postoperative assessment of hand function using Fugl-Meyer assessment, Jebsen-Taylor hand function test, and handheld dynamometry were performed at 3-monthly intervals for 1 year. Surgical outcomes were assessed as per the Odom criteria and Hirayama outcome questionnaire. RESULTS: Age at onset and duration of illness were 12-31 years (mean, 18 ± 2.7) and 1-96 months (32.7 ± 24.4), respectively. All patients had progressive weakness and wasting of the affected limb. Cord atrophy was seen in 97.1%, with epidural detachment and engorgement of the posterior epidural venous plexus in all. All patients underwent ACDF. Of these patients, 54% had an excellent/good outcome and 39% had a satisfactory outcome as per the Odom scale at last follow-up (mean, 44.9 ± 16.5 months) after surgery. Handheld dynamometry showed improvement from preoperative values to 1 year follow-up. Duration of illness and age at onset had a negative correlation and the preoperative Fugl-Meyer score had a positive correlation with improvement. CONCLUSIONS: ACDF resulted in remarkable improvement or stabilization in neurologic deficits in many patients with HD. Because motor disability ensues over time, early surgical intervention during the progressive phase is advocated.

Single-institution Series of Hirayama Disease in North America.

STUDY DESIGN: A retrospective chart review. OBJECTIVE: The aims of this study were to review pathophysiology, workup, and treatment for Hirayama disease (HD); and to assess outcomes from a single institution. SUMMARY OF BACKGROUND DATA: HD is a rare, painless, cervical myelopathy with distal upper extremity weakness, muscle wasting, and spinal cord atrophy. Disease progression-a consequence of repeat flexion injury-occurs up to 5 years from the initial diagnosis. METHODS: Single-institution review of pediatric HD patients from 2010 to 2020. RESULTS: Patients (n=10 male, n=2 female) presented in the second decade (14-20 y) with painless progressive distal upper extremity weakness and atrophy without sensory loss. Electromyography (n=12) demonstrated denervation in C7-T1 myotomes and flexion/extension magnetic resonance imaging showed focal cord atrophy and anterior displacement of the posterior dura with epidural enhancement in flexion. Treatment included observation and external orthoses (n=9) and anterior cervical discectomy with fusion (n=3). One of the 9 patients managed conservatively experienced further deterioration; no patient who underwent anterior cervical discectomy with fusion progressed. CONCLUSIONS: Patients with HD require a multidisciplinary approach to diagnosis and treatment to preserve function. Treatment is preventive and aims to minimize flexion injury by inhibiting motion across involved joints. First-line management is avoidance of neck flexion and use of rigid orthosis; in cases of failed conservative management and/or rapid clinical deterioration, surgical fixation can be offered.