Anterior Dislodgement of a Fusion Cage after Transforaminal Lumbar Interbody Fusion for the Treatment of Isthmic Spondylolisthesis

Transforaminal lumbar interbody fusion (TLIF) is commonly used procedure for spinal fusion. However, there are no reports describing anterior cage dislodgement after surgery. This report is a rare case of anterior dislodgement of fusion cage after TLIF for the treatment of isthmic spondylolisthesis with lumbosacral transitional vertebra (LSTV). A 51-year-old man underwent TLIF at L4-5 with posterior instrumentation for the treatment of grade 1 isthmic spondylolisthesis with LSTV. At 7 weeks postoperatively, imaging studies demonstrated that banana-shaped cage migrated anteriorly and anterolisthesis recurred at the index level with pseudoarthrosis. The cage was removed and exchanged by new cage through anterior approach, and screws were replaced with larger size ones and cement augmentation was added. At postoperative 2 days of revision surgery, computed tomography (CT) showed fracture on lateral pedicle and body wall of L5 vertebra. He underwent surgery again for paraspinal decompression at L4-5 and extension of instrumentation to S1 vertebra. His back and leg pains improved significantly after final revision surgery and symptom relief was maintained during follow-up period. At 6 months follow-up, CT images showed solid fusion at L4-5 level. Careful cage selection for TLIF must be done for treatment of spondylolisthesis accompanied with deformed LSTV, especially when reduction will be attempted. Banana-shaped cage should be positioned anteriorly, but anterior dislodgement of cage and reduction failure may occur in case of a highly unstable spine. Revision surgery for the treatment of an anteriorly dislodged cage may be effectively performed using an anterior approach.

Effect of lumbar angular motion on central canal diameter: positional MRI study in 491 cases / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lumbar spinal stenosis is a common problem that is receiving attention with the advent of novel treatment procedures. Prior positional MRI studies demonstrated lumbar canal diameter changes with flexion and extension. There have not been any studies to examine the amount of spinal canal diameter change relative to the amount of angular motion. The purpose of this study was to evaluate the correlation between the lumbar canal diameter change and the angular motion quantitatively.</p><p><b>METHODS</b>Positional MRI (pMRI) images for 491 patients, including 310 males and 181 females (16 years-85 years of age), were obtained with the subjects in sitting flexion 40 degree, upright, and with extension of 10 degrees within a 0.6 T Positional MRI scanner. Quantitative measurements of the canal diameter and segmental angle of each level in the sagittal midline plane were obtained for each position. Then the diameter change and angular motion were examined for correlation during flexion and extension with linear regression analysis.</p><p><b>RESULTS</b>The lumbar segmental angles were lordotic in all positions except L1-2 in flexion. The changes of canal diameters were statistically correlated with the segmental angular motions during flexion and extension (P < 0.001). The amount of canal diameter change correlated with the amount of angular change and was expressed as a ratio.</p><p><b>CONCLUSIONS</b>Positional MRI demonstrated the amount of spinal canal diameter change that was statistically correlated with the segmental angular motion of the spine during flexion and extension. These results may be used to predict the extent of canal diameter change when interspinous devices or positional changes are used to treat spinal stenosis and the amount of increased canal space may be predicted with the amount of angular or positional change of the spine. This may correlate with symptomatic relief and allow for improved success in the treatment of spinal stenosis.</p>

Old Atlantoaxial Rotary Subluxation Associated with High-riding Vertebral Arteries: Arthrodesis Using C1 Lateral Mass Screws and C2 Laminar Screws: A Case Report

To the best of our knowledge, there has been no domestic report on posterior atlantoaxial fusion with segmental screw fixation using C2 laminar screws and C1 lateral mass screws for atlantoaxial subluxation. We report the result of this operation performed in a patient with old atlantoaxial rotary subluxation who required posterior fusion. We chose this technique in this patient because wire fixation was not suitable due to osteoporosis, and transarticular screw fixation and use of C2 pedicle screws were not feasible due to the peculiar bony anatomy of the axis.

Revision of Atlantoaxial Fusion using Segmental Screw Fixation: Experience in Bilateral Posterior Arch Fracture of the Atlas Complicating Atlantoaxial Halifax Clamp Fixation: A Case Report / 대한척추외과학회지

A fracture of the posterior arch of the atlas is a rare complication of Halifax clamp fixation for atlantoaxial fusion. To the best of our knowledge, there is only one case reported reporting the English literature. Revision for this condition is challenging because of the difficulty in the surgical approach, internal fixation, and fusion. We report a case of bilateral fractures and nonunion of the posterior arch of the atlas and atlantoaxial nonunion after an atlantoaxial fusion procedure using Halifax clamp fixation, which resulted in persistent atlantoaxial instability and progressive myelopathy. Segmental screw fixation was performed using C1 lateral mass screws and C2 subarticular screws, along with intraarticular and extraarticular atlantoaxial inter-facet fusion.

Atlanto-occipital Assimilation Associated with Basilar Invagination, C1-2 Instability, C2-3 Block Vertebra,and C3-4 Retrolisthesis : A Case Report / 대한정형외과학회잡지

Congenital atlanto-occipital assimilation is frequently accompanied by basilar invagination and C1-2 instability. Occipitocervical fusion is required if these conditions cause neurological symptoms. Recently posterior fusion using occipitocervical screw fixation in the extension position has been introduced for the simultaneous decompression of the cervicomedullary junction compressed by basilar invagination, a reduction of atlantoaxial subluxation, and rigid fixation. However, it is a technically demanding procedure, and there is no domestic report of an experience with this procedure. We report a case of a patient with C2-3 block vertebra and C3-4 retrolisthesis in addition to congenital atlanto-occipital assimilation, basilar invagination and C1-2 instability. The patient underwent posterior fusion using occipitocervical screw fixation in the extension position.

External Fixation Of Lower Limb Fractures In Children / 대한정형외과학회잡지

PURPOSE: To evaluate the results and the usefulness of the external fixator for the treatment of the lower limb fractures in children. MATERIALS AND METHODS: We used 22 children fractures of lower limb treated with external fixator. There were 14 isolated femur or tibia fractures, 2 both femur and tibia fractures, 1 bilateral tibial fractures, 5 fractures associated with others, and were 10 open and 16 closed fracture. We assessed the axial alignment and leg-length discrepancy, and the range of motion of the joints and complications. RESULTS: The average union and fixation time were 8.1 and 9.5 weeks. Average of 2.4 degrees of varus or valgus and 3.8 degrees of anterior or posterior angulation were obtained. At follow-up, the range of LLD was -1.3 to +1.5cm. CONCLUSION: External fixator in lower limb fractures of children is useful to open fractures, multiple fractures, and unstable fractures to minimize complications.

Detection of Synovial Hypertrophy in Idiopathic Carpal Tunnel Syndrome Using Ultrasongraphy / 대한정형외과학회잡지

OBJECTS: Synovial thickness in carpal tunnel was measured by high-resolution ultrasonography to evaluate the relation of synovial hypertrophy in idiopathic carpal tunnel syndrome. MATERIALS AND METHODS: Thickness of synovium of flexor tendons in 46 hands of idiopathic carpal tunnel syndrome and 50 hands of normal control were measured quantitatively by high-resolution ultrasonography. The patients were classified into three groups according to the clinical severity: Group I had typical clinical symptoms and positive provocation test (17 cases) , Group II had sensory decreation on the dermatome of median nerve (21 cases) , and Group III had sensory decreation and thenar muscle weakness. The thickness of flexor tendons in the three groups and control group were statistically compared. RESULTS: The mean value of thickness of carpal tunnel syndrome was 1.06mm and that of control group was 0.87mm (p=0.012) . Positive correlation was revealed according to the clinically classified three groups. CONCLUSION: Synovial hypertrophy in carpal tunnel has positive relationships with idiopathic carpal tunnel syndrome, and it reveal possibly the progression of the disease.

Arthroscopic Treatment of Meniscal Cysts

PURPOSE: To assess the efficacy of arthroscopic decompression of the meniscal cyst. MATERIAL AND METHOD: From January 1996 to December 1997, 8 patients with meniscal cyst were treated by arthroscopic cyst decompression as well as partial meniscectomy of torn menisci. The average follow-up was 18.8 months(range: 12~35 months). There were 6 men and 2 women and the average age was 38.1 years(range: 26 to 56 years). Six(75%) patients had no history of trauma associated with their symptoms. All the meniscal cysts were associated with horizontal tear of the menisci. The arthroscopic partial meniscectomy consisted of gentle trimming of leading edge of the superior leaf and excision out to peripheral rim of the inferior leaf, followed by intraarticular cyst decompression using probe, punch for-ceps or shaver with pressure over the cyst. Postoperative results were assessed according to the evaluation form of Glasgow et al. RESULT: The ratio of medial-to-lateral cyst formation was 1:1. Meniscal cysts were always associated with horizontal tears of the meniscus. The patterns of horizontal tear consisted of 2 horizontal/cleav-age(25%), 2 horizontal/flap(25%), and 4 horizontal/ degenerative complex tears(50%). The sites of meniscal tears were the posterior horn-midbody junction of the medial meniscus in 4, the anterior horn-midbody junction of the lateral meniscus in 3 and the midbody of the lateral meniscus in 1. We could get excellent or good results in all the patients with no recurrence of the cyst. CONCLUSIONS: The treatment of the meniscal cyst can be entirely arthroscopic(partial meniscectomy and intraarticular decompression of the cyst) with predictable success.

Treatment of Brachymetatatsia / 대한정형외과학회잡지

A total of 16 metatarsal bones were treated for ten with brachymetatarsia using two different methods: single staged lengthening by bone graft(2 cases) and gradual distraction lengthening using unilateral external fixator(14 cases). Three cases of first metatasal bone and thirteen cases of fourth metatarsal bone were operated. All of the cases of the brachymetatarsia were congenital. The average amount of lengthening was 16.1 mm in gradual distraction lengthening while 10.5mm in single staged lengthening. Average percentile increase was 38.8% in gradual distraction lengthening and 23% in single staged lengthening. The average healing index of gradual distraction lengthening was 1.7(months/cm). Although single staged lengthening has advantage of cosmetics, gradual distraction lengthening using unilateral external fixator was thought to be effective functionally for metatarsal lengthening.

Treatment of Comminuted Trochanteric Fractures with Dynamic Hip Screw and DHS Trochanter Stabilizing Plate / 대한정형외과학회잡지

It has been emphasized that the treatment of choice for the trochanteric fracture of the femur is open reduction and rigid internal fixation. Regarding the stability of the fracture, most reports were focused on the comminution of the medial cortex, but few reports were paid attention to the additional fracture of the greater trochanter. This paper was aimed to evaluate the fragment of the greater trochanter on the maintenance of reduction. We treated 23 cases of unstable trochanteric fractures in which 16 cases were treated with Dynamic Hip Screw (DHS) alone, and 7 cases were treated with DHS and additional DHS Trochanter Stabilizing Plate (TSP). We compared the two groups and the results were as follows: 1. The average lag screw slipping distance was 17.1mm in DHS Group and 10.0mm in TSP Group. 2. The average distance of lateral displacement of greater trochanter over the trochantric fractures was 11.5mm in DHS Group and no change in TSP Group. The above results suggested that the comhined use of DHS Trochanter Stabilizing Plate with Dynamic Hip Screw provided good results in the treatment of uristable intertrochanteric fractures with completely detached greater trochanter and reverse oblique fracture.

Effects of RGD Protein on the Bone Resorptive Activity of Osteoclast / 대한정형외과학회잡지

Osteoclasts resorb bone by the hydrogen ions and proteolytic enzymes in the localize environment under the ruffled border. Before releasing hydrogen ion and enzymes, osteoclast should attach to bone surface very tightly and make a room to release enzymes and hydrogen ion in the center. Specialized attachment molecule in the cell membrane, such as integrin, is associated with specific noncollagenous protein in the matrix, which has specific amino acid sequence (Arginine-Glycine- Aspartic acid sequence). We may speculate that osteoclast action would be decreased if the integrin is blocked by antibody or RGD protein. In this study, the osteoclasts were cultured on the coverslip or bone slice with or without RGD protein in the culture medium, and numbers of growing giant cells were much less in group with RGD protein. The number resorption pits, formed on mineralized bone slice, was also lower in the group adding RGD protein in the medium. And we made a conclusion that the osteoclastic bone resorption was inhibited by soluble RGD protein.