Hip Flexor Weakness Research Articles

6424 From Hyperparathyroidism To Neurologic Crisis: A Tale Of Brown Tumor And Spinal Cord Compression

Abstract Disclosure: A. Kormanis: None. M. Anderson: None. M. McKnight: None. H. Darapu: None. Background/Objective: In this case, we present a rare and severe consequence of secondary hyperparathyroidism, a Brown tumor leading to spinal cord compression, in a young adult with end-stage renal disease. Case Report: A 26-year-old male with a medical history of polycystic kidney disease and IgA Nephropathy complicated by ESRD, history of brown cell tumors (s/p surgery) was admitted for hospitalization due to hypocalcemia after presenting to the Emergency Department with right lower extremity weakness. Examination revealed right hip flexor weakness and right foot clonus. Lab results showed serum calcium of 10.4 mg/dL . MRI displayed a 2.5cm X 3.7 cm soft tissue mass with circumferential encroachment of the epidural space leading to severe spinal canal stenosis of T4-T5 at the site of prior Brown tumor resection. Ultimately, the patient underwent subtotal parathyroidectomy with left cervical thymectomy, leading to an intra-operative PTH drop from >3500 to 247 pg/mL. Discussion: In the context of treating vertebral brown tumors, the consensus suggests that parathyroidectomy plays a crucial role in achieving both clinical and radiographical amelioration of the tumor. However, in cases like ours where paresis is present, surgical decompression of the tumor becomes imperative. Conclusion: The development of Brown tumors is a severe and rare long-term complication for hyperparathyroidism, and the location of a Brown tumor in the thoracic spine causing symptomatic cord compression is even more rare. Presentation: 6/2/2024

Clinical Outcomes of Prone Transpsoas Lumbar Interbody Fusion: A 1-Year Follow-Up.

Lateral lumbar interbody fusion (LLIF) is commonly used to address various lumbar pathologies. LLIF using the prone transpsoas (PTP) approach has several potential advantages, allowing simultaneous access to the anterior and posterior columns of the spine. The aim of this study was to report the 1-year outcomes of LLIF via PTP. This is a retrospective review of 97 consecutive patients who underwent LLIF via PTP. Radiographic parameters, including lumbar-lordosis, segmental-lordosis, anterior disc height, and posterior disc height, were measured on preoperative, initial-postoperative, and 1-year postoperative imaging. Patient-reported outcomes measures, including Oswestry Disability Index, visual analog scale (VAS), pain EQ5D, and postoperative complications, were reviewed. Ninety-seven consecutive patients underwent 161 levels of LLIF. Fifty-seven percent underwent 1-level LLIF, 30% 2-level LLIF, 6% 3-level LLIF, and 7% 4-level LLIF. The most common level was L4 to L5 (35%), followed by L3 to L4 (33%), L2 to L3 (21%), and L1 to L2 (11%). Significant improvements were noted at initial and 1-year postoperative periods in lumbar-lordosis (2° ± 10°, P = 0.049; 3° ± 9°, P = 0.005), segmental-lordosis (6° ± 5°, P < 0.001; 5° ± 5°, P < 0.001), anterior disc height (8 mm ± 4 mm, P < 0.001; 7 mm ± 4 mm, P < 0.001), and posterior disc height (3 mm ± 2 mm, P < 0.001; 3 mm ± 2 mm, P < 0.001). Significant improvements were seen in Oswestry Disability Index at 6 weeks (P = 0.002), 6 months (P < 0.001), and 1 year (P < 0.001) postoperatively; pain EQ5D at 6 weeks (P < 0.001), 6 months (P < 0.001), and 1 year (P < 0.001) postoperatively; and leg and back visual analog scale at 2 weeks (P < 0.001), 6 months (P < 0.001), and 1 year (P < 0.001) postoperatively. The average length of stay was 2.5 days, and the most common complications were ipsilateral hip flexor pain (46%), weakness (59%), and contralateral hip flexor pain (29%). PTP is a novel way of performing LLIF. These 1-year data support that PTP is an effective, safe, and viable approach with similar patient-reported outcome measures and complications profiles as LLIF performed in the lateral decubitus position.

1070 Muscle Mechanomyography (MMG) for Peripheral Nerve Monitoring During Lateral Lumbar Fusion: The New Kid on the Block?

INTRODUCTION: The lateral transpsoas approach has become a valuable minimally invasive option in lumbar spine surgery to achieve fusion, decompression, and deformity correction. However, femoral nerve injury during psoas retraction remains a significant concern, especially in the lower spinal levels. A newer alternative to electromyography (EMG), muscle mechanomyography (MMG) measures muscle fiber oscillation during contraction, providing a more specific and quantifiable response with a high signal to noise ratio. These characteristics make MMG an attractive option for intraoperative neuromonitoring (ION) in minimally invasive spine surgery. METHODS: Patients who underwent LLIF between 2018-2021 with MMG ION were included and compared to a historical cohot of patients who underwent LLIF from 2016-2021 with EMG ION. The femoral nerve palsy rate defined by ipsilateral thigh numbness, hip flexor, or quadricep weakness immediately post operatively were collected for both groups. Patients were re-evaluated at 3 month and 1 year follow up intervals. RESULTS: The rate of ipsilateral thigh numbness, hip flexor, and quadricep weakness at hospital discharge were 14.6% (6/41), 9.8% (4/41), and 7.3% (3/41) respectively for the MMG group, comparable to 14.8% (9/61), 23% (14/61), and 14.8% (9/61) observed in the EMG control group. Improvement in thigh numbness and leg weakness was observed for both groups at 3 month and 1 year follow up. No patients with leg weakness had less than antigravity strength. There were no statistically significant difference amongst patient demographics for both cohorts. CONCLUSIONS: In conclusion, MMG appears to be clinically equivalent to EMG as an intraoperative modality for femoral nerve monitoring in LLIF procedures. Further research is needed to evaluate the additional clinical advantages proposed by mechanomyography, such as low signal interference and quantifiable nerve localization.

Clinical and oncologic outcomes of posterior only total en bloc spondylectomy for spinal metastasis involving third lumbar vertebra: A case series.

A posterior-only total en bloc spondylectomy (TES) of the L3 level was deemed a highly intricate surgical procedure, necessitating the preservation of the L3 nerve root to prevent neurological deterioration. Despite bilateral preservation efforts of the L3 nerve roots, neurological deterioration proved unavoidable. This study aims to present the clinical, neurologic, and oncologic outcomes of spinal metastasis patients who underwent a posterior-only approach TES, encompassing the L3 vertebra. All patients with L3-involved spinal metastasis undergoing posterior TES between January 2018 and January 2022 were investigated. The primary outcomes considered were the local recurrence rate and manual muscle testing of the lumbar myotome. Secondary outcomes included Frankel neurological status, operative time, blood loss, perioperative and postoperative complications, and Eastern Cooperative Oncology Group score. Five patients with TES involving L3 (three females) met the inclusion criteria. All patients had solitary metastases (three in the lungs, 2 in the breasts). Postoperatively, all patients experienced weakness of the hip flexors, but they were able to ambulate independently 12 months after surgery. One patient exhibited adjacent segment (L2) disease progression and underwent corpectomy 18 months after TES. No local recurrences at the surgical site were detected on magnetic resonance imaging at the 1-year follow-up. Posterior-only TES for L3-involved vertebrae yielded excellent results in the local control of metastatic disease. Despite hip flexor weakness, all patients were able to regain independent ambulation after 12 months. TES can offer favorable clinical and oncological outcomes in patients with solitary spinal metastases.

FRI226 Ectopic Cushing’s Syndrome Of Unknown Primary Origin With Etomidate Use

Abstract Disclosure: C. Ohammah: None. J. Lloyd: None. T. Abdulwahid: None. R. Tangri: None. C. Musgrove: None. K. Selk: None. Background: Ectopic Cushing's syndrome (ECS) is rare and requires adrenolytic agents to control hypercortisolism until a definitive plan can be made to treat the underlying cause. We present a case of ECS of unknown primary origin causing immunosuppression due to the hypercortisolism that responded with etomidate infusion. Case: A 61-year-old male who presented to the hospital after a few weeks of increasing weakness, dyspnea, and hemoptysis. In the months prior to his admission, he was found to have persistent hypokalemia, COVID pneumonia, and new onset diabetes mellitus. On admission, his examination was remarkable for proximal hip flexor weakness. Labs were significant for metabolic alkalosis, hyperglycemia (A1c 7.7%) and persistent hypokalemia requiring about 300 mEq of potassium daily. CT chest, abdomen and pelvis was remarkable for aspiration pneumonia, vertebral compression fracture, and bilateral adrenal enlargement. Blood cultures grew Staphylococcus Aureus (MSSA) (suspected lung source) and Candida albicans. Treatment with vancomycin and caspofungin was initiated and narrowed to cefazolin after speciation. His MSSA cleared rapidly however, fungemia was persistent after 1.5 weeks of treatment. MRI brain was unremarkable for causative lesion. Further testing revealed elevated morning cortisol (136.2ug/dL) confirmed on repeated testing and elevated ACTH (653pg/mL). Serum metanephrines were normal. A high-dose dexamethasone suppression was unremarkable. In the following days, he developed respiratory failure secondary to a spontaneous hemothorax requiring intubation and ICU admission. He was started on an etomidate infusion given abnormal liver enzymes and unavailability of metyrapone. The infusion was titrated every 6 hours based on cortisol levels. His liver enzymes improved and ketoconazole was added but later discontinued due to development of thrombocytopenia. His cortisol level decreased (21.5ug/dL) and fungemia cleared. Arrangement for bilateral adrenalectomy was made but the patient decompensated and developed shock requiring pressors. After a goals of care discussion, he was transitioned to comfort measures and eventually passed. Conclusion: ECS is rare, and the diagnosis is challenging and often delayed. Ectopic ACTH can result from various malignancies. Medical management with adrenolytic agents should be considered early in the management of ECS until a definitive plan is made. Etomidate, ketoconazole, metyrapone, and mitotane can be used to treat hypercortisolism to achieve medical adrenalectomy. Bilateral adrenalectomy should be considered in patients without adequate response to adrenolytic agents. This case describes the severity of hypercortisolism from an ectopic ACTH production causing refractory hypokalemia and immunosuppression resulting in fatal infections. We highlight the use of etomidate to control hypercortisolism. Presentation: Friday, June 16, 2023

489 Complications Associated With Single Position Prone Lateral Lumbar Interbody Fusion: A Systematic Review and Meta-Analysis

INTRODUCTION: Lateral lumbar interbody fusion (LLIF) is a workhorse surgical approach for lumbar arthrodesis. There is now emerging interest in performing single position surgery in which both LLIF and pedicle screw fixation are performed in the prone position. To date, most studies of prone LLIF are of poor quality and without long-term follow up; and as such, the complication profile related to this novel approach is not well known. METHODS: A systematic review of the literature and a meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All studies reporting prone LLIF were assessed for inclusion. Studies not reporting complication rates were excluded. RESULTS: A total of 10 studies met inclusion criteria and were included in the analysis. Overall, 286 patients were treated with prone LLIF across these studies with an average of 1.3 (0.2) levels per patient. There were 18 reported intra-operative complications including cage subsidence (3.8%), rupture of the anterior longitudinal ligament (ALL) (2.3%), cage repositioning (2.1%), aborted prone interbody placement (0.82%), and durotomy (0.6%). There were no reported major vascular or peritoneal injuries. A total of 68 post-operative complications occurred. These included thigh/groin sensory symptoms (13.3%), hip flexor weakness (17.8%), wound infection (1.9%), psoas hematoma (1.3%), motor neural injury (1.2%), and revision surgery (3.8%). CONCLUSIONS: Single position LLIF in the prone position appears to be a safe surgical approach with a low complication profile. Longer term follow up and prospective studies are needed in order to better characterize long-term complication rates related to this approach.

184 Clinical Outcomes of the Prone Transpsoas Lateral Lumbar Interbody Fusion for Degenerative Lumbar Spine Disease: A Multicentre Study

INTRODUCTION: The prone transpsoas lateral lumbar interbody fusion (PTP) is a novel technique for degenerative lumbar spine disease. However, there is a paucity of the literature on the clinical outcomes of this procedure, with all the published being of a small sample size. METHODS: A retrospective electronic medical records review was conducted in ten centers for patients who underwent PTP. We collected the intraoperative data (operative time, estimated blood loss [EBL], intraoperative complications [anterior longitudinal ligament (ALL) rupture, cage subsidence, vascular and visceral injuries), postoperative complications, the patient-reported outcome measures (PROMS) such as back pain visual analogue scale (VAS), and hospital stay. RESULTS: A total of 350 patients were included in the study. There was a significant improvement in the mean VAS by 4.4 ± 6.7 (p &lt; 0.001). 2.8% had ALL rupture, 1.2% had cage subsidence, 0.4% had a vascular injury, and none had visceral injuries. The mean operative time was 229.9 ± 144 minutes, the mean EBL was 134.3±210.2 mL, and the mean hospital stay was 2.6 ± 2.2. In regard to postoperative complications, there was 8.9% new sensory symptoms, 6% transient hip flexor weakness, 1.4% wound infection, 1.4% cage subsidence, 0.6% psoas hematoma, 0.3% ureteric injury, 0.3% small bowel obstruction/ischemia, and 1.6% 90-days readmission. CONCLUSIONS: Multicenter consecutive case series show that PTP is well tolerated and has satisfactory clinical outcomes.

Early Clinical Outcomes of the Prone Transpsoas Lumbar Interbody Fusion Technique.

The prone transpsoas (PTP) approach for lateral lumbar interbody fusion (LLIF) is a relatively novel technique. Currently, little is known about its associated complications and early patient-reported outcomes. The aim of this study was to investigate the effect of LLIF performed via the PTP approach on sagittal radiographic parameters, patient-reported outcome measures (PROMs), and rates of complications. A retrospective review was performed of 82 consecutive patients who underwent LLIF via a PTP technique. Lumbar lordosis (LL), segmental lordosis (SL), anterior disc height (ADH), and posterior disc height (PDH) were measured on preoperative, initial postoperative, and 3-month postoperative radiographs. PROMs including the Oswestry Disability Index (ODI); the visual analog scale (VAS); and pain portions of the EQ5D, VAS back, and VAS leg ratings were collected at the preoperative and subsequent postoperative visits. Length of hospital stay and postoperative complications related to the procedure were recorded. Significant improvements were seen at the initial (4.5° ± 8.6°, P < 0.001) and 3-month (4.4° ± 7.2°, P < 0.001) postoperative periods for LL, as well as SL (6.8° ± 4.8°, P < 0.001; 6.7° ± 4.4°, P < 0.001), ADH (8.0 mm ± 3.6, P < 0.001; 7.4 mm ± 3.6, P < 0.001), and PDH (3.3 mm ± 2.4, P < 0.001; 3.1 mm ± 2.5, P < 0.001). Significant improvements were seen at 3 months postoperatively for ODI (P < 0.001), EQ5D pain (P = 0.016), VAS leg (P < 0.001), and VAS back (P < 0.001). The average length of stay was 2.7 ± 4.5 days. The most common complications were ipsilateral thigh pain/numbness (45.1%), ipsilateral hip flexor weakness (39.0%), and contralateral thigh pain/numbness (14.6%). While early PROMs and correction of sagittal radiographic parameters show promising results for the PTP approach for LLIF, it is not without risks. PTP interbody fusion is an emerging technique that allows for simultaneous access to the anterior and posterior columns of the lumbar spine. This early case series demonstrates significant improvement in functional outcomes and lumbar lordosis with a safety profile comparable to other well-established techniques.

Comparison of Posterior Pedicle Screw Fixation and Lateral Fixation in the Extreme Lateral Interbody Fusion in Lumbar Degenerative Disease Patients with Osteopenia or Osteoporosis.

Nowadays, with the increasing proportion of osteoporosis in patients with lumbar degenerative diseases, doctors are facing the choice of intraoperative internal fixation methods. The purpose of this study was to compare and assess the clinical results of posterior bilateral pedicle screw fixation and lateral fixation in the extreme lateral interbody fusion (XLIF) in patients with osteopenia or osteoporosis. The retrospective review was performed on 67 degenerative lumbar diseases patients with osteopenia or osteoporosis who underwent XLIF in our hospital from January 2018 to July 2021. Patients in this study were classified into lateral screw (LS) group, lateral self-locking plate (LP) group, and bilateral pedicle screw (BPS) group. The functional evaluation factors containing Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) of leg pain, and VAS of low back pain, radiological factors such as disc height (DH), lumbar lordotic (LL) angle, segmental lordotic (SL) angle, cage subsidence degree and interbody fusion degree were compared. Primary outcomes: no differences were observed with regards to the incidence of complications among LS, LP and BS group (P < 0.05). The JOA and leg pain VAS were significantly improved after operation (P < 0.05) and all groups demonstrated similar improvements in the leg pain VAS and JOA score (P > 0.05). When comparing VAS of leg pain and JOA scores, no differences were identified among LS, LP and BPS groups (P > 0.05). There are four thigh sensory complaint, one hip flexor weakness and one thigh pain occurred and no death was observed. There were significantly better DH, LL angle, SL angle, cage subsidence degree and interbody fusion degree in the BPS group than in LS and LP groups 1 year after surgery (P < 0.05). The DH loss ratio, LL angle loss ratio, SL angle loss ratio in the BPS group was significantly lower than in the LP and LS groups (P < 0.05). The 12-month SL angle improvement rate in the BPS group was significantly higher than in the LP and LS groups (20.20± 14.69, 0.73 ± 4.68, 6.20 ± 12.31, P < 0.05). the BPS patients had significantly worse intraoperative blood loss and operation time than LS and LP patients (P < 0.05). In lumbar diseases patients with osteopenia or osteoporosis, the bilateral pedicle screw fixation has better orthopedic effect than lateral internal fixation, and can better maintain the stability of the spine in the long-term follow-up, which is a better choice in XLIF surgery.

Rates of Postoperative Complications and Approach-related Neurological Symptoms After L4-L5 Lateral Transpsoas Lumbar Interbody Fusion Compared With Upper Lumbar Levels.

This was a retrospective comparative study. To compare the likelihood of approach-related complications for patients undergoing single-level lateral lumbar interbody fusion (LLIF) at L4-L5 to those undergoing the procedure at upper lumbar levels. LLIF has been associated with a number of advantages when compared with traditional interbody fusion techniques. However, potential risks with the approach include vascular or visceral injury, thigh dysesthesias, and lumbar plexus injury. There are concerns of a higher risk of these complications at the L4-L5 level compared with upper lumbar levels. A retrospective cohort review was completed for consecutive patients undergoing single-level LLIF between 2004 and 2019 by a single surgeon. Indication for surgery was symptomatic degenerative lumbar stenosis and/or spondylolisthesis. Patients were divided into 2 cohorts: LLIF at L4-L5 versus a single level between L1 and L4. Baseline characteristics, intraoperative complications, postoperative approach-related neurological symptoms, and patient-reported outcomes were compared and analyzed between the cohorts. A total of 122 were included in analysis, of which 58 underwent LLIF at L4-L5 and 64 underwent LLIF between L1 and L4. There were no visceral or vascular injuries or lumbar plexus injuries in either cohort. There was no significant difference in the rate of postoperative hip pain, anterior thigh dysesthesias, and/or hip flexor weakness between the cohorts (53.5% L4-L5 vs. 37.5% L1-L4; P =0.102). All patients reported complete resolution of these symptoms by 6-month postoperative follow-up. LLIF surgery at the L4-L5 level is associated with a similar infrequent likelihood of approach-related complications and postoperative hip pain, thigh dysesthesias, and hip flexor weakness when compared with upper lumbar level LLIF. Careful patient selection, meticulous use of real-time neuromonitoring, and an understanding of the anatomic location of the lumbar plexus to the working corridor are critical to success.

Femoral Neuropathy Following Extreme Lateral Interbody Fusion (XLIF) Procedure: A Case Report

Background The extreme lateral interbody fusion approach (XLIF) is a surgical technique introduced two decades ago for spinal fusions. However, little has been published on the particular complications associated with this surgical technique and the rehabilitation. The purpose of this report is to describe a case of post-operative complication of retroperitoneal hematoma following XLIF with subsequent femoral neuropathy and the physical therapy intervention approach applying the repetitions in reserve (RIR) concept. Case Presentation A 60-year-old female presented with severe right hip flexor and quadriceps weakness from a retroperitoneal hematoma following a right-sided XLIF procedure for severe right L4-5 radiculopathy. Post-surgical physical therapy treatment and 6-month outcomes are described. Outcome and Follow Up By post-operative week 12, the patient obtained a knee brace that eliminated her falls due to quadriceps weakness. At 6 months post-operatively, she demonstrated significantly improved quadriceps and hip flexor strength (from 1/5 and 2+/5, respectively, to 3+/5), and improved lower extremity functional scale score, from 30 to 58. She was also able to complete a 6-minute walk test and ambulated 128 m. Discussion Significant improvement in motor function and functional outcomes was noted by post-operative month six. The role of physical therapy was to focus on the timing of muscle reactivation using electrical stimulation and progressive resistance exercises using the RIR concept as nerve function returned. JOSPT Cases 2022;2(3):162–165. Epub: 21 June 2022. doi:10.2519/josptcases.2022.10895

Towards a More Realistic Appraisal of Complications Following Staged Lateral Lumbar Interbody Fusion: A Single Institution Series.

Retrospective cohort study. With steadily increasing implementation of far lateral approaches in spine surgery, surgeons can utilize the advantages of different approaches synergistically to ensure an optimal patient outcome. Our single institution study aimed to assess the complication rates of patients who underwent a lateral interbody fusion as the index procedure and additional anterior or posterior instrumentation as part of a planned staged surgical reconstruction effort. This study was approved by our institutional review board (STUDY2021000113). We included 576 patients who received a lateral lumbar interbody fusion (LLIF) as the index procedure followed by transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF) or anterior lumbar interbody fusion (ALIF) between 2016 and 2020. Primary outcomes were complications identified during the initial inpatient stay, which were categorized into approach-related and secondary complications. Secondary outcomes tracked up to 6 years post-surgery. The overall complication rate was 19.2% (10.5% approach related, 8.7% secondary complications). Significant intraoperative hemorrhage (mean 659.3mL vs 131.4mL, P < .01) was the most common approach related complication with an incidence of 4%, followed by temporary hip flexor weakness in 2.6%. A permanent (femoral) nerve damage was verified in 1 patient. The most common secondary complication was impaired wound healing in 12 patients (2.1%). We identified a 7.1% (41 of 576 patients) rate of revision surgery, on average after 372 days (±34 days). We recorded an overall complication rate of 19.2% for staged adult deformity corrective surgeries utilizing far lateral interbody fusions at several lumbar levels followed by a more comprehensive posterior surgical reconstruction.

Arthroscopic Ischial Tuberoplasty: Treatment of Ischiofemoral Impingement

Background: Ischiofemoral impingement is a rare but increasingly recognized as a source of hip pain. Its etiology is often multifactorial and can be due to congenital, iatrogenic, or extra-articular pathology. Prior literature has described lesser trochanter osteoplasty and iliopsoas release for the treatment of ischiofemoral impingement, but postoperative hip flexor weakness has been noted with this technique. We present a novel technique for the treatment of ischiofemoral impingement, with resection of the ischial tuberosity. Indications: Patients with ischiofemoral impingement that remain symptomatic despite nonsurgical management, or patients with persistent gait abnormalities, are considered for surgery. Technique Description: In the prone position, direct posterior and posterolateral arthroscopic portals are created in the gluteal fold. The posterior femoral cutaneous and sciatic nerve are identified. Fluoroscopy is used to identify the region of impingement on the ischial tuberosity and the overlying hamstring tendon is elevated off the tuberosity. An arthroscopic burr is used to resect the tuberosity. Fluoroscopy is utilized to confirm adequate resection. This is combined with a dynamic examination under direct arthroscopic visualization with the hip in an extended, adducted, and externally rotated position. To repair the hamstring tendon, 2 double-loaded anchors are placed into the ischium, the sutures of which are used to repair the hamstring tendons using a horizontal mattress configuration. Patients undergo a stepwise postoperative physical therapy protocol, followed by a functional testing profile prior to return to competitive sport. Results: Significant improvements in patient-reported outcomes have been reported following treatment of ischiofemoral impingement, with some studies reporting Hip Outcome Score—Activities of Daily Living (HOS-ADL) &gt;90 at 2 years postoperatively. Athletes have been able to return to sport at a mean 5.6 months after surgery. Large studies have yet to report on outcomes compared with nonsurgical or open techniques. Discussion/Conclusion: Recent advancements in endoscopic techniques have allowed for adequate visualization and release of ischiofemoral impingement. We present our endoscopic technique of ischial tuberoplasty, which, compared to lesser trochanter osteoplasty and iliopsoas release, may reduce the incidence of postoperative hip flexor weakness.

Ataxia and Parkinsonism in a Woman With a VCP Variant and Long-Normal Repeats in the SCA2 Allele.

We present the case of a 46-year-old woman with gradually progressive ataxia, parkinsonism, and neuropathy. Symptoms started at age 29 years with speech impairment and difficulty walking. At presentation, she had mild midline ataxia and dysarthria. Left hand rest tremor began at age 33 years. Over the next decade, she developed parkinsonism and lower extremity weakness, which was more prominent than ataxia (Videos 1 and 2 ). Her parkinsonism was responsive to levodopa, and over time, she developed motor fluctuations. She also developed urinary retention and constipation. Medical history was otherwise notable for lumbar radiculopathy, ankylosing spondylitis, elevated anti-nuclear antibodies, migraine, and depression. Current examination reveals appendicular and gait ataxia, dysarthria, parkinsonism (left predominant), bilateral hip flexor weakness and foot drop, length-dependent decrease in pinprick sensation, and hyperreflexia (bilateral Babinski and jaw jerk reflexes). She is adopted and has 2 healthy teenaged sons. She is apparently of European descent but does not know her family history. The authors thank Christopher Gomez, MD, PhD (University of Chicago, IL), for providing ataxia exome and RFC-1 expansion data and discussing the case.

Reliability and sensitivity of radiographic measures of hip dysplasia in childhood Charcot-Marie-Tooth disease.

Hip dysplasia is a lack of femoral head coverage and disruption of hip and acetabular alignment and congruency, with severity ranging from mild subluxation in nascent at-risk hips to complete dislocation. Presentation of hip dysplasia in neuromuscular conditions can be sub-clinical or associated with a limp with or without hip pain, abductor and flexor weakness and reduced hip range of motion. Untreated hip dysplasia leads to early onset osteoarthritis requiring hip arthroplasty in early adulthood. Hip dysplasia occurs in 6-20% of children with Charcot-Marie-Tooth disease, however little is known about the reliability and sensitivity of detection on plain film pelvic radiographs. 14 common measures of hip dysplasia on anteroposterior pelvis radiographs were independently assessed by 2 orthopaedic specialists in 30 ambulant children with Charcot-Marie-Tooth disease. Hip health was also categorised based on clinical impression to assess the sensitivity of radiographic measures to identify hip dysplasia status. 8 measures (acetabular index, head width, lateral centre-edge angle, lateral uncoverage, medial joint width, migration percentage, neck shaft angle, triradiate status) exhibited 'excellent' reliability between clinical evaluators. 5 of the 30 patients (17%) were identified as having nascent hip dysplasia. Reliable radiographic measures that significantly distinguished between nascent hip dysplasia and healthy hips were acetabular index, lateral centre edge angle, medial joint width and migration percentage. We have identified a subset of reliable and sensitive radiographic hip measures in children with Charcot-Marie-Tooth disease to prioritise during hip screening to mitigate the deleterious effects of hip dysplasia, pain and disability in adulthood.

Complications in Extreme Lateral Interbody Fusion (XLIF®): A Retrospective Study in Siriraj Hospital

Background: Extreme Lateral Interbody Fusion (XLIF®) is a well-known transpsoas approach technique that confers advantages including excellent visualization, easy access to the lumbar disc, accommodation for a large anterior graft, restoration of disk height and lumbar alignment, and indirect decompression. However, no study in Thailand has investigated early postoperative complications after spinal fusion with XLIF surgery. Objective: To determine the early postoperative complication rates among Thai patients that underwent spinal fusion with XLIF procedure. Materials and Methods: The present study was a retrospective chart review to evaluate perioperative and early postoperative complications in patients that underwent spinal interbody fusion with XLIF procedure and were followed-up for a minimum of three months at the Department of Orthopedic Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand between 2015 and 2019. Results: One hundred eighteen patients, including 82 females and 36 males, with a mean age of 64.2 years and 165 levels, that were operated upon, were included. Eighty patients (67.8%) underwent one-level fusion, 29 (24.6%) had two-level fusion, and 9 (7.6%) underwent three-level fusion. Immediate postoperative complications occurred in 66 patients (55.9%), consisting of eight (6.7%) with medical complications, 57 (48.3%) with surgical complications, and one (0.8%) with combined medical and surgical complications. Postoperative complications were resolved within three months after surgery in 48 patients. Forty-one patients (34.7%) had postoperative proximal lower limb neuropathy. Only 10 patients (24.4%) still had neuropathy at the 3-month follow-up, but it did not affect their function. Conclusion: Postoperative proximal limb neuropathy, including thigh numbness, pain, or hip flexor weakness, had a high prevalence in the present study despite intraoperative neurophysiologic monitoring; however, most cases resolved by the 3-month follow-up. Patient education about potential nerve irritation complication is recommended, and meticulous preoperative radiographic assessment and careful step-by-step intraoperative surgical approach may reduce the rates of these postoperative complications. Keywords: Extreme lateral interbody fusion; Complications; Neuropathy; Postoperative

Navigation and Robotic-Assisted Single-Position Prone Lateral Lumbar Interbody Fusion: Technique, Feasibility, Safety, and Case Series

Single-position prone lateral interbody fusion is a recently introduced technical modification of the minimally invasive retroperitoneal transpsoas approach for lateral lumbar interbody fusion (LLIF). Several technical descriptions of single-position prone LLIF have been published with traditional fluoroscopy for guidance. However, there has been no investigation of either three-dimensional computed tomography-based navigation for prone LLIF or integration with robotic assistance platforms with the prone lateral technique. This study evaluated the feasibility and safety of spinal navigation and robotic assistance for single-position prone LLIF. Retrospective review of medical records and a prospectively acquired database for a single center was performed to examine immediate and 30-day clinical and radiographic outcomes for consecutive patients undergoing single-position prone LLIF with spinal navigation and/or robotic assistance. Nine patients were treated, 4 women and 5 men. Mean age was 65.4 years (range, 46-75 years), and body mass index was 30.2 kg/m2 (range, 24-38 kg/m2). The most common surgical indication was adjacent segment disease (44.4%), followed by pseudarthrosis (22.2%), spondylolisthesis (11.1%), degenerative disc disease (11.1%), and recurrent stenosis (11.1%). Postoperative approach-related complications included pain-limited bilateral hip flexor weakness (4/5) and pain-limited left knee extension weakness (4/5) in 1 patient (11.1%) and right lateral thigh numbness and dysesthesia in 1 patient (11.1%). All cages were placed within quarters 2-3, signifying the middle portion of the disc space. There were no instances of misguidance by navigation. Integration of spinal navigation and robotic assistance appears feasible, accurate, and safe as an alternative to fluoroscopic guidance for single-position LLIF.

Complications associated with L4-5 anterior retroperitoneal trans-psoas interbody fusion: a single institution series.

Lateral lumbar interbody fusion (LLIF), first described in the literature in 2006 by Ozgur et al., involves direct access to the lateral disc space via a retroperitoneal trans-psoas tubular approach. Neuromonitoring is vital during this approach since the surgical corridor traverses the psoas muscle where the lumbar plexus lies, risking injury to the lumbosacral plexus that could result in sensory or motor deficits. The risk of neurologic injury is especially higher at L4-5 due to the anatomy of the plexus at this level. Here we report our single-center clinical experience with L4-5 LLIF. A retrospective chart review of all patients who underwent an L4-5 LLIF between May 2016 and March 2019 was performed. Baseline demographics and clinical characteristics, such as body mass index (BMI), medical comorbidities, surgical history, tobacco status, operative time and blood loss, length of stay (LOS), and post-op complications were recorded. A total of 220 (58% female and 42% male) cases were reviewed. The most common presenting pathology was spondylolisthesis. The average age, BMI, operative time, blood loss, and LOS were 64.6 years, 29 kg/m2, 214 min, 75 cc, and 2.5 days respectively. A review of post-operative neurologic deficits revealed 31.4% transient hip flexor weakness and 4.5% quadricep weakness on the approach side. At 3-week follow-up, 9.1% of patients experienced mild hip flexor weakness (4 or 4+/5), 0.9% reported mild quadricep weakness, and 9.5% reported anterior thigh dysesthesias; 93.2% of patients were discharged home and 2.3% were readmitted within the first 30 days post discharge. Female sex, higher BMI and longer operative time were associated with hip flexor weakness. LLIF at L4-5 is a safe, feasible, and versatile approach to the lumbar spine with an acceptable approach-related sensory and motor neurologic complication rates.

Rectus-sparing approach to the periacetabular osteotomy in adolescents preserves hip flexion strength.

PurposeThe classic periacetabular osteotomy (PAO) approach can result in hip flexor weakness in adolescents. The rectus-sparing approach (PAO-RS) preserves the origin of the rectus femoris tendon which may prevent hip flexor weakness and improve functional outcome.MethodsThis is a prospective analysis of adolescents treated with a PAO or PAO-RS. The PAO group included 24 hips/21 patients (18 female, meanage 16 years (sd 4)); the PAO-RS group included ten hips (eight female, mean age 16 years (sd 1)). Preoperatively, the PAO group had decreased hip flexion strength compared with the PAO-RS group (83 Nm/kg versus 102 Nm/kg). A subset of PAO patients (n = 13 hips/12 patients, nine female, mean age 15 years (sd 3)) were matched for preoperative flexion strength to the PAO-RS group. Radiographic parameters, modified Harris hip score (mHHS), isokinetic hip strength and instrumented motion analysis preoperatively, six months and one-year postoperatively were compared.ResultsThere were no differences in preoperative deformity, postoperative correction or degree of correction between groups. Hip flexor strength decreased significantly at six months in the PAO group compared with the PAO-RS group (-35 Nm/kg versus -7 Nm/kg; p = 0.012), as did hip flexion pull-off power (1.33 W/kg PAO versus 1.76 W/kg PAO-RS; p = 0.010). Hip flexion strength improved from six months to one year in the PAO group, with no significant differences in strength at one year between groups (80 Nm/kg versus 90 Nm/kg). There were no differences between groups in mHHS any time point; both groups improved significantly postoperatively.ConclusionPreserving the rectus femoris may lead to improved short-term hip flexor strength and pull-off power. Further assessment at long-term follow-up is needed to determine if this strength leads to improved functional outcomes.Level of EvidenceII

Reoccurring discogenic low back pain (LBP) after discoblock treated by oblique lumbar interbody fusion (OLIF)

ObjectiveTo determine the efficacy of OLIF in the treatment of reoccurring discogenic low back pain (LBP) after discoblockMethodsWe included 108 patients with LBP that was suspected to be discogenic (such as high intensity zone, Schmorl’s nodes, Modic changes Type I, etc.), from August 2015 to August 2017. All patients underwent discography, and patients whose LBP was confirmed to be discogenic received discoblock. Patients who had reoccurring pain after discoblock underwent OLIF. Perioperative parameters and complications were recorded. The VAS and Oswestry Disability Index (ODI) were assessed at preoperation, and 1 week and 1, 3, 6, and 12 months after the surgery. The fusion rate was evaluated.ResultsOf 108 patients, 89 were confirmed to have discogenic LBP, and 32/89 patients with reoccurring LBP pain after discoblock underwent OLIF. Twenty-eight patients were followed up for ≥ 1 year. The OLIF operation lasted for 92 ± 34 min. Blood loss during the operation was 48 ± 15 ml. The mean incision length was 3.0 ± 0.6 cm. The average length of stay was 4.8 ± 1.9 days. The VAS and ODI scores decreased from 8.1 ± 1.7 preoperatively to 0.9 ± 0.4, and from 71.2 ± 11.3 to 9.3 ± 3.1, 12 months postoperatively, respectively. The total incidence of complications was 15.6%, including 2 cases of cage subsidence, 2 cases of ipsilateral hip flexor weakness, and 1 case of ipsilateral anterior thigh pain. All symptoms relieved or disappeared during follow-up. The fusion rate was 96.9%.ConclusionsReoccurring discogenic LBP after discoblock should be considered as a suitable group for treatment by OLIF.