Surgical technique of spine-shortening vertebral osteotomy for adult tethered cord syndrome: a case report and review of the literature.

BACKGROUND: Miyakoshi et al. reported three cases of tethered cord syndrome treated by spine-shortening vertebral osteotomy, which provided relief of the patients' symptoms with no complications. Although the details of these cases were described in a previous report, the surgical technique was not thoroughly explained. In the present report, we describe the details of our procedure with reference to a fourth case. CASE PRESENTATION: A 47-year-old Asian woman was admitted to our hospital with a 1-year history of worsening leg numbness and urinary dysfunction. Magnetic resonance imaging revealed a low-lying conus medullaris extending to the level of S2 and surrounded by fat tissue at that level. We diagnosed her condition as adult tethered cord syndrome, and spine-shortening vertebral osteotomy was planned. The target level for the osteotomy was L2. Bilateral pedicle screw implants were placed at L1 and L3 using an anterior-posterior image intensifier. In this procedure, it is essential to use monoaxial screws inserted exactly parallel to the rostral endplates of each vertebral body; this ensures appropriate alignment between the L1 caudal endplate and the L2 osteotomy surface. The upper one-third of the lamina of L2 was resected, and the bilateral two-thirds of the pedicle of L2 was removed with a surgical air drill. After exposure of the lateral side of the L1-2 disc, discectomy was performed with a knife and curette. Following complete discectomy of L1-2, the upper vertebral body of L2 was removed with a surgical air drill. After complete removal of the vertebral body, a straight rod was connected to two screws and applied pressure between the screws. Two polyethylene tapes were applied to the L2 lamina and bilateral rods. CONCLUSION: Spine-shortening osteotomy that preserves the caudal one-third of the pedicle and lamina with one-above and one-below instrumentation successfully reduced the spinal cord tension without causing neural damage.

How Much Experience is Required to Acquire the Skills to Independently Perform Spine Surgery? What Milestones are Needed for Successful Surgery?

Purpose: To assess the number of surgeries needed to acquire the necessary skills to perform spine surgery independently. Patients and Methods: A questionnaire on 12 different spinal procedures was sent to orthopedic surgeons affiliated with the spine teams of orthopedic departments at either the Akita University or Sapporo Medical University. Participants were asked to identify whether they (A) could independently perform each procedure, (B) could perform each procedure with the assistance of a senior doctor, or (C) were unable to perform each procedure. Those whose response was (A) were asked how many surgeries were required to acquire the necessary skills. Those who responded to (B) or (C) were asked how many surgeries they believed were required to acquire the skills necessary to operate independently. Participants also responded to 10 questions on surgical training techniques and rated the usefulness of each method. Results: A total of 55 spine surgeons responded to the questionnaire. Group A required significantly fewer surgeries in the following categories to become independent than required Group C: upper cervical spine surgery (7.3/19.3), anterior cervical decompression/fusion (6.7/28.8), posterior cervical decompression/fusion (9.5/27.3), lumbar discectomy (12.6/26.7), endoscopic lumbar discectomy (10.2/24.2), spinal tumor resection (6.5/37.2), and spinal kyphosis surgery (10.3/32.3). Over 80% of participants responded that the following were effective methods: "surgeries where a senior doctor is the main surgeon, and the respondent is the assistant and observer"; "surgeries where the respondent is the main surgeon, and a senior doctor is an assistant"; "self-study using surgery manuals, articles, and textbooks"; and "training through video surgery sessions". Conclusion: Surgeons who do not perform specific procedures independently require more surgical experience than those who operate independently. Our results may help develop more efficient training methods for spine surgeons.

Degenerative Lumbar Spondylolisthesis Patients With Movement-related Low Back Pain Have Less Postoperative Satisfaction After Decompression Alone.

STUDY DESIGN: Retrospective analysis of prospectively collected multicenter observational data. OBJECTIVE: The aim was to examine the preoperative factors affecting postoperative satisfaction following posterior lumbar interbody fusion (PLIF) and microendoscopic muscle-preserving interlaminar decompression (ME-MILD) in patients with degenerative lumbar spondylolisthesis (DLS). SUMMARY OF BACKGROUND DATA: The technique involved in DLS surgery may either be decompression alone or decompression-fixation. Poor performance may occur after either of these surgical treatments. The author hypothesized that evaluating the correlation between preoperative quality of life and postoperative performance would aid in determining the optimal procedure. MATERIALS AND METHODS: This study included 138 patients who underwent surgery for 1-level mild DLS. The authors performed PLIF for 79 patients and ME-MILD for 59 patients. When the satisfaction subscale of the Zurich Claudication Questionnaire exceeded 2 points, postoperative satisfaction was considered poor. The clinical characteristics were investigated. Responses to preoperative health-related quality of life questionnaires, such as the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), short form-36 health survey (SF-36), and visual analog scale, were compared between the satisfied and unsatisfied groups. RESULTS: In the PLIF group, no endogenous factors influenced postoperative satisfaction. The ME-MILD cohort's satisfied and unsatisfied patients differed significantly in terms of preoperative lumbar spine dysfunction ( P <0.001) items of the JOABPEQ, role physical ( P =0.03), and role emotional ( P =0.03) items of the SF-36. A strong correlation ( r =-0.609 P =0.015) was found between preoperative lumbar spine dysfunction and postoperative satisfaction. CONCLUSIONS: In the ME-MILD group, preoperative lumbar spine function was correlated with postoperative satisfaction. Decompression alone may be ineffective in cases with decreased lumbar spine function prior to surgery. The degree of low back pain on movement should be considered before selecting the surgical method. LEVEL OF EVIDENCE: 3.

Deep Angiomyxoma of the Thigh That Is Difficult to Diagnose: A Case Report and Literature Review.

We present an extremely rare case of deep angiomyxoma (DAM) in the thigh that was misdiagnosed as desmoid-type fibromatosis. A 40-year-old Japanese woman presented with a mass on the left thigh. The histological diagnosis by needle biopsy was desmoid-type fibromatosis; the tumor grew slowly and was resected 4 years later. The histological diagnosis from the resected tumor was DAM. As of 16 months post-surgery, the patient has not noticed any local recurrence. Although DAM in a lower extremity is extremely rare, clinicians must be aware of its possible occurrence in areas relatively close to the pelvis.

Tumor Lysis Syndrome due to Eribulin Administration for Metastatic Undifferentiated Pleomorphic Sarcoma of the Buttock.

Tumor lysis syndrome (TLS) is a complication of cancer treatment that requires urgent intervention. It is extremely rare in the treatment of soft tissue sarcoma (STS) of the limbs or trunk, and there are currently no reports of TLS occurrence from eribulin therapy. We report the case of a 78-year-old woman with an undiffer-entiated pleomorphic sarcoma on the right buttock. We initiated chemotherapy with intravenous eribulin mesylate. Deterioration of renal function, mild hyperkalemia, hyperuricemia, hypocalcemia, and hyperphos-phatemia were confirmed on examination, suggesting the presence of TLS. We present an extremely rare case of TLS from eribulin for STS.

Changes in Invasiveness and Latent Infection Rate Associated with Switching the Approach in Total Hip Replacement.

PURPOSE: Muscle-sparing approaches for total hip replacement (THR) involve learning curves. This study aimed to clarify changes in invasiveness and infection rate with changes in approach. METHODS: One surgeon changed the approach of THR from Dall's approach (Dall) to anterolateral modified Watson-Jones approach (OCM). Another changed from Dall to a direct anterior approach (DAA). Another 3 surgeons changed from posterolateral approach (PL) to OCM. Subjects were 150 cases, comprising the last 25 cases with conventional approaches and the first 25 cases with new approaches (Dall to OCM: 25 + 25; Dall to DAA: 25 + 25; PL to OCM: 25 + 25 cases). Differences in operative time, bleeding volume, hospital stay, haemoglobin (Hb), white blood cell count, lymphocyte count, creatine kinase (CK) and C-reactive protein (CRP) were investigated. RESULTS: In the change from Dall to OCM, only hospital stay decreased. In the change from Dall to DAA, hospital stay and CRP decreased, but bleeding volume increased. In the change from PL to OCM, operative time, CRP and CK decreased, but Hb also decreased. Cases with lymphocyte count <1000/µL or lymphocytes comprising <10% of total white blood cells at around day 4 after surgery were defined as latent infection cases. In these cases, operative time was longer, Hb was lower and CK was higher. CONCLUSION: Introducing muscle-sparing approaches improved many markers of invasiveness, but some items deteriorated. In the early stages of introducing a new approach, choosing cases without obesity and without high muscle volume may reduce the risk of infection.

Open tibial shaft fracture in a boy with autism spectrum disorder treated using a ring external fixator: A case report.

Autism spectrum disorder covers a group of behaviorally defined disorders that may result in the patient having difficulty staying calm during medical treatments, due to anxiety-related overreactions. Tibial fractures are the third most common pediatric long-bone fracture. Conservative treatment is selected in many cases, but surgical treatment may be selected in cases of open fracture and no treatment policy has been established. We described the case of a 6-year-old boy with autism spectrum disorder who was unable to stay calm due to anxiety and required sedation. We diagnosed open tibial shaft fracture (Orthopaedic Trauma Association classification 42A1, 4F2A; Gustilo classification type 1). On the day of injury, we performed osteosynthesis using a ring external fixator and primary closure of the open wound. Full weight-bearing was permitted from immediately after surgery. No significant complications were observed postoperatively, and the external fixator was removed 84 days postoperatively. No abnormal alignment of the lower leg, leg-length discrepancy or range of motion disorder was identified. To the best of our knowledge, no other reports have described use of a ring external fixator for open tibial shaft fractures in children with autism spectrum disorder. Using a ring external fixator appears helpful for open tibial shaft fractures in children who are unable to stay calm due to autism spectrum disorder, because there is no need to limit weight-bearing immediately after surgery. For Gustilo classification type 1 pediatric open fracture, primary closure of the open wound is safe after sufficient bone fixation.

Ultrasound-Guided Peripheral Nerve Blocks Performed by Orthopedic Surgeons: A Retrospective, Multicenter Study in Akita Prefecture, Japan.

The shortage of doctors is a societal problem, especially in rural areas such as Akita Prefecture, Japan. Therefore, it is not unusual in Akita for orthopedic surgeons to perform upper and lower limb surgeries under ultrasound-guided peripheral nerve blocks managed by the operators themselves. Multicenter studies of ultrasound-guided peripheral nerve blocks performed by orthopedic surgeons have not been reported. The purpose of this study was to clarify the safety and reliability of ultrasound-guided peripheral nerve blocks performed by orthopedic surgeons in Akita. A total of 1,674 upper extremity surgery cases operated under ultrasound-guided peripheral nerve blocks at 8 hospitals in Akita prefecture from April 2016 to April 2018 were investigated retrospectively. These blocks were performed by a total of 37 orthopedic surgeons, including senior surgeons and residents. In 321 of the 1,674 cases (19%), local anesthetics were added to the surgical field. Two cases with special factors were converted to general anesthesia. There were 2 cases of complications associated with the nerve block, but they were all transient and recovered promptly. The block site and the hospital where the block was performed showed a significant relationship with the addition of local anesthetics to the surgical site (P < 0.001). Surgery time, age at surgery, and surgical site showed no significant relationships with the addition of local anesthetics. The volume of the anesthetic used for the nerve block showed a significant inverse relationship with the addition of local anesthetics (P=0.040). Many orthopedic surgeons in Akita prefecture began to perform ultrasound-guided peripheral nerve blocks, which had a reliable anesthesia effect with no noticeable complications, whether performed by residents or senior orthopedic surgeons, and this is a useful anesthetic technique for orthopedic surgeons.

Herniation of the cauda equina into the facet joint through a pseudomeningocele: A case report and literature review.

BACKGROUND: Incidental durotomy is a well-known complication of spinal surgery. It can lead to persistent cerebrospinal fluid leakage resulting in significant secondary complications. Here, we present a case in which the cauda equina herniated into a pseudomeningocele that penetrated a facet joint, leading to lower extremity radiculopathy warranting surgical correction. CASE DESCRIPTION: One year ago, a 67-year-old male underwent a partial left L4-L5 laminectomy. At surgery, a durotomy was repaired with a nylon suture and reinforced with a fat patch. He subsequently presented with severe left lower extremity radiculopathy and a partial cauda equina syndrome. On MR, the cauda equina had herniated into a pseudomeningocele that penetrated the left facet joint. Once the defect was repaired at surgery, the patient's symptoms improved. CONCLUSION: It is critical to correctly repair an intraoperative durotomy to avoid further neurological deficits that may include cauda equina herniation into pseudomeningoceles penetrating facet joints.

Preoperative medications is one of the factor affecting patient-reported outcomes after total hip arthroplasty.

Although the reported clinical outcomes of total hip arthroplasty (THA) for hip osteoarthritis are satisfactory, not all patients are completely satisfied. Thus, there is interest in predicting postoperative satisfaction before surgery. The influence of comorbidities and preoperative medications on the incidence of complications and duration of hospitalization following THA has become apparent. However, studies about the associations of preoperative medication with clinical outcomes of THA are limited. Therefore, this study aimed to clarify the relationship between preoperative medications and postoperative patient-reported outcomes. This retrospective cross-sectional multicenter study enrolled post-THA patients (79 patients, 90 hips) who were examined from February to March 2019 in eight general hospitals. Outcome measures included patient-reported outcome as Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) score. Preoperative medications were investigated from medical records. Medications were categorized, and analgesics were categorized into non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, pregabalin, duloxetine, neurotropin (an extract from inflammatory rabbit skin inoculated by vaccinia virus), and opioid. To identify the factors associated with JHEQ score, the patients were divided into lower (<55 score) and higher (≥55) JHEQ score groups. Spearman rank correlation coefficient (r) showed significant difference between the total number of preoperative medications and postoperative JHEQ movement subscale (r = -0.37, p < 0.01), mental subscale (r = -0.29, p < 0.01), and JHEQ (r = -0.30, p < 0.01) scores. In the multiple logistic regression analysis, only the total number of preoperative medications was identified as a risk factor for lower JHEQ score (p < 0.01). This study clarified an inverse correlation between the total preoperative medication count and postoperative outcomes and found that larger total count of preoperative medications is a risk factor of poor postoperative patient-reported outcomes of THA.

Proximal junctional fracture and kyphosis after long spinopelvic corrective fixation for adult spinal deformity.

BACKGROUND: Proximal junctional fractures (PJFx) are the main cause for proximal junctional kyphosis (PJK), a complication of adult spinal deformity surgery. This study investigated risk factors for PJFx when performing long spinopelvic corrective fixation with lateral interbody fusion from T9 to ilium. METHODS: This was a retrospective study of 43 patients with a minimum follow-up of 2 years. Radiographic measurements including thoracic kyphosis (TK), sagittal vertical axis (SVA), T1 pelvic angle (TPA), proximal junctional angle (PJA), lumbar lordosis (LL), lower LL, and pelvic tilt were measured preoperatively, one-month postoperatively, and at final follow up. TK and LL were also measured in a fulcrum backward-bending position preoperatively. RESULTS: At final follow-up, PJK was found in 30/43 patients (69.8%); 20.9% of the cases had PJFx (9 patients). TPA (preoperative, and one-month postoperative) was significantly higher in the PJFx group than in the other groups. The differences in TPA, TK, and PJA between preoperative and one-month postoperative measurements in the PJFx group were significantly higher than those in the other groups. At final follow up, SVA was significantly higher in the PJFx group than in the "PJK without PJFx" group. TPA and TK were significantly higher in the PJFx group than in the other groups. PJA was significantly different between all groups. CONCLUSION: Preoperative large TPA was the only risk factor for PJFx. Preoperative flexibility of the thoracolumbar spine and overcorrection of sagittal deformity were not related to PJFx or PJK.

Thin Cervical Spinal Cord Between Ossifications of the Ligamentum Flavum and the Posterior Longitudinal Ligament: Case Report and Literature Review.

BACKGROUND: Cervical ossification of the ligamentum flavum (OLF) is a rare condition; however, the coexistence of OLF and ossification of the posterior longitudinal ligament (OPLL) is extremely uncommon. These can exist simultaneously and cause thinning of the cervical spinal cord. Sufficient decompression, dural ossification, semispinalis dissection, and postoperative kyphosis were evaluated. We report the successful treatment of coexisting cervical OLF and OPLL. CASE DESCRIPTION: A 70-year-old man had been experiencing weakness in the left knee and clumsiness in the left hand for 6 months. Hemiparesis was considered; however, magnetic resonance imaging revealed a cervical spinal lesion. Hence a spine surgeon diagnosed the patient with severe stenosis with OLF at the C2-C3 levels and OPLL at the C2-C4 levels. The patient presented with spastic gait and left-hand motor weakness. Computed tomography scan revealed the disappearance of the black line, indicating dural ossification surrounding the OLF. OPLL was observed in 61.5% of the C2 spinal canal. The K-line was (-); however, the alternative K-line between the C1 and C7 level was (+). Posterior laminectomy at the C2-C3 levels and laminoplasty at the C4-C7 levels with muscle preservation resulted in sufficient decompression. The patient's symptoms improved, and cervical alignment was maintained 2 years after surgery. CONCLUSIONS: An alternative K-line comprised successful treatment for coexisting cervical OLF and OPLL. Surgeons must evaluate the severity of adhesion, damage of the paraspinal muscles, and necessity of posterior corrective surgery along with the patient's comorbidities and possible postoperative complications.

Successful treatment of valgus knee osteoarthritis involving external tibial torsion with a double level osteotomy: A case report.

INTRODUCTION: Abnormal torsion of the lower leg affects the alignment of the knee joint and foot, and causes impairment of both knee joint function and gait. We here present a successful adult case treated with a double level osteotomy at the distal femur and tibia. PRESENTATION OF CASE: A 59-year-old woman complained of right knee pain for three years and had a deformity of her right lower limb since childhood. An advanced right tibial external torsion deformity with valgus alignment was revealed. We performed a double level osteotomy to correct both the valgus knee osteoarthritis and the external tibial torsional deformity. At the 2 year follow-up, the patient could run without pain and sit normally. DISCUSSION: The indications for surgery for abnormal rotation in the lower extremity are also not clear. In addition, most prior surgical reports on torsional deformity of the lower leg have been on childhood cases. Surgical treatment of valgus knee osteoarthritis involving external tibial torsion in adult has been rarely reported. CONCLUSIONS: In our current report, we present an adult case of valgus knee osteoarthritis involving external tibial torsion that was successfully treated using a double level osteotomy. A longer follow-up is still needed however despite these positive outcomes. LEVEL OF EVIDENCE: Ⅴ.

Diagnosis and Surgical Treatment of Thoracic Dorsal Arachnoid Web: A Report of Two Cases.

INTRODUCTION: An arachnoid web (AW) is a relatively rare disease and shows clinical symptoms and radiological findings similar to those of an arachnoid cyst (AC) or spinal cord herniation (SCH). Since the operative procedures for an AW are generally different from those intrathecal disorders, correct preoperative differential diagnosis is important. The purposes of this study were to report the usefulness of magnetic resonance imaging (MRI) and computed tomography (CT) myelography for diagnosing AW and to show the histological findings and clinical results. Case Description. Two patients, a 79-year-old man and a 43-year-old woman, are presented. The primary diagnoses were AC with ossification of the ligamentum flavum and epidural hematoma, respectively, in previous hospitals. They were finally diagnosed by the characteristic MRI and CT myelogram finding called the "scalpel sign." Histological findings showed epithelial cells and fibrous tissue derived from arachnoid tissues and microcalcifications. After surgery, the scalpel sign has vanished, and aggravation of their symptoms was prevented. CONCLUSION: An AW is refractory, but early detection by MRI and CT myelography and early treatment improve outcomes after surgery.

Initial Rotational Instability of the Tapered Wedge-Shaped Type Cementless Stem.

BACKGROUND: Because the tapered wedge-shaped type cementless stem has a small anteroposterior width and a low occupation rate in the medullary space, postoperative rotational instability and stem subsidence due to inadequate proximal fixation are concerns. The purpose of this study was to clarify the relationship between the rotational instability of the tapered wedge-shaped type cementless stem and femoral canal shape. METHODS: A total of 61 primary total hip arthroplasties with the tapered wedge-shaped type cementless stem Accolade® TMZF (11 males, 50 females; mean age 60 years) from January 2012 to June 2015 who underwent computed tomography before surgery and within 4 weeks and 1 year after surgery were evaluated. The preoperative femoral neck anteversion angle, preoperative femoral canal flair index, the degree of postoperative stem subsidence within 1 year after operation, and the degree of rotational change in the stem setting angle within 1 year after operation were investigated. RESULTS: The mean preoperative femoral neck anteversion angle was 32.2° ± 17.8° (0°-69°), and the mean preoperative canal flair index was 3.68 ± 0.58 (2.44-5.55). There were no stem subsidence cases within 1 year after operation. The mean degree of rotational change in the stem from immediately to 1 year after surgery was -0.4° ± 1.7° (-3°-3°). There was no significant correlation between the canal flair index and the rotational change in the stem. In addition, the mean difference between the preoperative femoral neck anteversion angle and the stem rotational angle immediately after surgery was only 1.3° ± 5.3° (-29°-15°). CONCLUSIONS: In all cases, including stove-pipe cases, the degree of rotational change in the Accolade® TMZF stem from immediately to 1 year after surgery was within 3°. In other words, regardless of femoral canal shape, the tapered wedge-shaped type cementless stem has little initial rotational instability.

Cervical meningioma resection including the inner dura through an open-door laminoplasty using hydroxyapatite spacers: A case report.

BACKGROUND: The ideal surgery for spinal cord tumors is complete resection to prevent recurrence. However, it should be accomplished safely/effectively without risking increased morbidity. Here, we report a cervical meningioma that was totally resected, including the inner dura, through a laminoplasty performed with hydroxyapatite (HA) spacers. CASE DESCRIPTION: A 61-year-old Asian male presented with a symptomatic intradural extramedullary C4-C6 cervical meningioma. At surgery, this required resection of the inner dural layer through an open-door laminoplasty. Preservation of the outer dural layer facilitated a watertight closure and the avoidance of a postoperative cerebrospinal fluid (CSF) fistula. Notably, the laminoplasty utilized HA spacers which were magnetic resonance (MR) compatible allowing for future follow-up studies to evaluate for tumor recurrence. At 5-year follow-up, the tumor had not recurred, the patient was asymptomatic, and alignment was maintained. CONCLUSION: Gross total resection of an intradural extramedullary C4-C6 cervical meningioma was performed with removal of just the inner dural layer. Preservation of the outer dural layer allowed for a watertight closure and the avoidance of a postoperative CSF leak. Further, laminoplasty using HA spacers allowed for successful tumor resection, adequate fusion/stabilization, while not interfering with future MR studies (e.g., HA MR compatible).

Impact of Acridine Orange in Patients With Local Recurrent Soft Tissue Sarcoma.

BACKGROUND/AIM: Local recurrence in soft tissue sarcoma (STS) is a risk factor of worse prognosis. Although a few studies have shown that adjuvant therapy with acridine orange (AO) is effective for local control of primary STS, there have been no reports examining its effectiveness for local recurrence. PATIENTS AND METHODS: This retrospective study included 36 patients with first local recurrence of STS. Of them, 23 patients received wide excision without AO therapy (Wide group); the other 13 patients received marginal excision with AO therapy (AO group). We compared re-recurrence rates between these two groups. RESULTS: The total re-recurrence rate was 43.5% in the Wide group and 46.2% in the AO group. There was no significant difference in local re-recurrence-free survival and overall survival between the two groups. CONCLUSION: Adjuvant AO therapy combined with a marginal excision suppresses local re-recurrence rates of individuals with local STS recurrence.

Effectiveness of circular hexapod external fixation with soft tissue reconstruction in treating severe knee dislocation due to burn scarring: a case report.

BACKGROUND: Severe varus deformity and soft tissue injury caused by a burn around a complex knee dislocation is a rare injury. Soft tissue reconstruction and deformity correction with circular hexapod external fixation of the knee and hinged total knee arthroplasty (TKA) are challenging and can lead to major complications if not performed appropriately. We present a case in which a combination of soft tissue reconstruction, circular hexapod external fixation, and TKA was used treat severe knee dislocation due to burn scarring. CASE PRESENTATION: We report the case of a 58-year-old woman who presented for knee surgery with soft tissue reconstruction, deformity correction with circular hexapod external fixation, and hinged TKA for a severe complex deformity and soft tissue injury caused by a burn injury at 6 months of age. The left leg was shorter by 35 mm in terms of functional leg length discrepancy. She walked with a limp, with a marked varus deformity of the left knee during the stance phase of walking. After a 3-stage repair, the patient was able to walk without assistance, confirming improvement of mobility. CONCLUSION: The treatment method was an effective use of a combination of soft tissue reconstruction, circular hexapod external fixation, and rehearsal surgery using a 3D printed bone model of the modular rotating hinge component of TKA, which was successfully used to treat a severe knee dislocation due to burn scarring. This staged surgery maintained the leg length and ultimately achieved a satisfactory alignment.

Pyogenic Atlantoaxial Rotational Dislocation Representing Adult Torticollis with Vertebral Artery Occlusion: A Case Report and Review.

BACKGROUND: Pyogenic atlantoaxial rotational dislocation is a rare but life-threatening condition. Disease progression damages the soft tissue and bony structure, resulting in spinal cord or brain stem compression. Rapid and correct diagnosis could enable successful treatment. However, few studies have been reported, and the characteristics of a successful treatment course are not well known. In addition, our case presented with vertebral artery (VA) occlusion. Here we present a report of successful treatment of pyogenic atlantoaxial rotational dislocation representing adult torticollis with VA occlusion. CASE DESCRIPTION: A 67-year-old woman with neck pain and high fever was treated for suspected meningitis. Although her fever improved, pain persisted for several weeks. Examinations mostly showed characteristics of an infection with destructive atlantoaxial rotational dislocation; however, positive uptake with positron emission tomography, no anomalies with diffusion-weighted magnetic resonance imaging, and VA occlusion indicated the presence of a tumor lesion. After VA embolization and Halo reduction/stabilization, biopsy and blood culture revealed pyogenic infection. Antibiotics with rigid stabilization improved the inflammation and allowed definitive occipitocervical fixation, resulting in an uneventful postoperative course and painless bony fusion 2 years postoperatively. CONCLUSIONS: VA involvement should be examined for safe treatment. Stabilization is warranted to improve chronic inflammation. Knowledge regarding the characteristic treatment course could enable successful treatment planning and may prove to be lifesaving.