OBJECTIVE: To identify the factors that are associated with rod slippage and to study the pattern of achieved length gain with a standard distraction methodology.
SUMMARY OF BACKGROUND DATA: Ability to achieve successful magnetically controlled growing rod (MCGR) distraction is crucial for gradual spine lengthening. Rod slippage has been described as a failure of internal magnet rotation leading to a slippage and an inability to distract the rod. However, its onset, significance, and risk factors are currently unknown. In addition, how this phenomenon pertains to actual distracted lengths is also unknown.
METHODS: A total of 22 patients with MCGR and at least six distraction episodes were prospectively studied. Patients with rod slippage occurring less than six distraction episodes were considered early rod slippage whereas those with more than six episodes or have yet to slip were grouped as late rod slippage. The association of parameters including body habitus, maturity status, age of implantation, total number of distractions, months of distraction from initial implantation, initial and postoperative Cobb angle, T1-T12, T1-S1, T5-T12 kyphosis, curve flexibility, instrumented length, and distance between magnets in dual rods and between the magnets and apex of the curve with early or late onset of rod slippage were studied. Differences between expected and achieved distraction lengths were assessed with reference to rod slippage episodes and rod exchanges to determine any patterns of diminishing returns.
RESULTS: Patients had mean age of 7.1 years at diagnosis with mean follow-up of 49.8 months. A mean 32.4 distractions were performed per patient. Early rod slippage occurred in 14 patients and late rod slippage occurred in eight patients. Increased height, weight, body mass index, older age, increased T1-12 and T1-S1 lengths, and less distance between magnets were significantly associated with early rod slippage. Expected distraction lengths did not translate to achieve distraction lengths and reduced gains were only observed after achieving one-third of the allowable distracted length in the MCGR. Length gains return to baseline after rod exchange.
CONCLUSION: This is the first study to specifically analyze the impact of rod slippage on distraction lengths and the risk factors associated with its onset and frequency. Increased body habitus and reduced distance between internal magnets significantly influenced rod slippage events. Diminishing returns in distracted length gains were only observed after a period of usage.
LEVEL OF EVIDENCE: 3.
METHODS: We prospectively recruited patients with Adolescent Idiopathic Scoliosis (AIS) scheduled for PSF surgery. The anatomical locations of pain were divided into four: (1) surgical wound pain; (2) shoulder pain; (3) neck pain; and (4) low back pain. The anatomical locations of pain were charted using the visual analogue pain score at intervals of 12, 24, 36, 48 hours; and from day-3 to -14. Patient-controlled analgesia (morphine), use of celecoxib capsules, acetaminophen tablets and oxycodone hydrochloride capsule consumption were recorded.
RESULTS: A total of 40 patients were recruited. Patients complained of surgical wound pain score of 6.2±2.1 after surgery. This subsequently reduced to 4.2±2.0 by day-4, and to 2.4±1.3 by day-7. Shoulder pain scores of symptomatic patients peaked to 4.2±2.7 at 24 hours and 36 hours which then reduced to 1.8±1.1 by day-8. Neck pain scores of symptomatic patients reduced from 4.2±1.9 at 12 hours to 1.8±1.1 by day-4. Low back pain scores of symptomatic patients reduced from 5.3±2.3 at 12 hours to 1.8±1.1 by day- 12.
CONCLUSIONS: Despite the presence of different anatomical locations of pain after surgery, surgical wound was the most significant pain and other anatomical locations of pain were generally mild. Surgical wound pain reduced to a tolerable level by day-4 when patients can then be comfortably discharged. This finding provides useful information for clinicians, patients and their caregivers.
PURPOSE: To report the outcome of 50 patients with spinal metastases treated with minimally invasive stabilization (MISt) using fluoroscopic guided percutaneous pedicle screws with/without minimally invasive decompression.
OVERVIEW OF LITERATURE: The advent of minimally invasive percutaneous pedicle screw stabilization system has revolutionized the treatment of spinal metastasis.
METHODS: Between 2008 and 2013, 50 cases of spinal metastasis with pathological fracture(s) with/without neurology deficit were treated by MISt at our institution. The patients were assessed by Tomita score, pain score, operation time, blood loss, neurological recovery, time to ambulation and survival.
RESULTS: The mean Tomita score was 6.3±2.4. Thirty seven patients (74.0%) required minimally invasive decompression in addition to MISt. The mean operating time was 2.3±0.5 hours for MISt alone and 3.4±1.2 hours for MISt with decompression. Mean blood loss for MISt alone and MISt with decompression was 0.4±0.2 L and 1.7±0.9 L, respectively. MISt provided a statistically significant reduction in visual analog scale pain score with mean preoperative score of 7.9±1.4 that was significantly decreased to 2.5±1.2 postoperatively (p=0.000). For patients with neurological deficit, 70% displayed improvement of one Frankel grade and 5% had an improvement of 2 Frankel grades. No patient was bed-ridden postoperatively, with the average time to ambulation of 3.4±1.8 days. The mean overall survival time was 11.3 months (range, 2-51 months). Those with a Tomita score <8 survived significantly longer than those a Tomita score ≥8 with a mean survival of 14.1±12.5 months and 6.8±4.9 months, respectively (p=0.019). There were no surgical complications, except one case of implant failure.
CONCLUSIONS: MISt is an acceptable treatment option for spinal metastatic patients, providing good relief of instability back pain with no major complications.
METHODS: A modified Delphi study was used. A total of 70 statements were presented, using an online platform, over three consensus-seeking rounds, to participants with experience in the hospital care of patients with acute vertebral fragility fractures from UK-based specialist societies. Participants rated the level of their agreement with each statement on a 5-point Likert scale. Consensus was defined at 70% of respondents choosing either agree/strongly agree or disagree/strong disagree. Over the first two rounds, statements not reaching consensus were modified in subsequent rounds, and new statements proposed by participants and agreed by the research team could be added.
RESULTS: There were 71 participants in the first round, 37 in the second round and 28 (most of whom were geriatricians) in the third round. Consensus was reached in 52 statements covering fracture diagnosis, second-line imaging, organisation of hospital care, pain management and falls and bone health assessment. Consensus was not achieved for whether vertebral fragility fractures should be managed in a specific clinical area.
DISCUSSION: These findings provide the basis for the development of clinical guidelines and quality improvement initiatives. They also help to justify research into the merits of managing acute vertebral fragility fracture patients in a specific clinical area.
OBJECTIVE: This study looked into whether crossbar can reliably measure Upper Instrumend Vertebra (UIV) tilt angle intraoperatively and accurately predict the UIV tilt angle postoperatively and at final follow-up.
SUMMARY OF BACKGROUND DATA: Postoperative shoulder imbalance is a common cause of poor cosmetic appearance leading to patient dissatisfaction. There were no reports describing the technique or method in measuring the UIV tilt angle intraoperatively. Therefore, this study was designed to look into the reliability and accuracy of the usage of intraoperative crossbar in measuring the UIV tilt angle intraoperatively.
METHODS: Lenke 1 and 2 Adolescent Idiopathic Scoliosis patients who underwent instrumented Posterior Spinal Fusion using pedicle screw constructs with minimum follow-up of 24 months were recruited for this study. After surgical correction, intraoperative UIV tilt angle was measured using a crossbar. Immediate postoperative and final follow up UIV tilt angle was measured on the standing anteroposterior radiographs.
RESULTS: A total of 100 patients were included into this study. The reliability of the intraoperative crossbar to measure the optimal UIV tilt angle intraoperatively was determined by repeated measurements by assessors and measurement by different assessors. We found that the intra observer and inter observer reliability was very good with intraclass correlation coefficient values of >0.9. The accuracy of the intraoperative crossbar to measure the optimal UIV tilt angle intraoperatively was determined by comparing this measurement with the postoperative UIV tilt angle. We found that there was no significant difference (P>0.05) between intraoperative, immediate postoperative, and follow-up UIV tilt angle.
CONCLUSIONS: The crossbar can be used to measure the intraoperative UIV tilt angle consistently and was able to predict the postoperative UIV tilt angle. It was a cheap, simple, reliable, and accurate instrument to measure the intraoperative UIV tilt angle.
Purpose: To report the perioperative and radiological outcomes of single-stage posterior passive correction and fusion (SSPPCF) in adolescent patients who present with congenital scoliosis.
Overview of Literature: The surgical treatment for congenital scoliosis is complex. There is no definitive guide on surgical options for skeletally matured adolescent patients who have congenital scoliosis.
Methods: Patients with congenital scoliosis who underwent SSPPCF using a pedicle screw system were reviewed. We identified the following three surgical indications: (1) hemivertebra or wedge vertebra over the thoracic or thoracolumbar region with structural lumbar curves, (2) hemivertebra or wedge vertebra at the lumbar region with significant pelvic obliquity or sacral slanting, and (3) mixed or complex congenital scoliosis. The demographic, perioperative, and radiographic data of these patients were collected.
Results: Thirty-four patients were reviewed. The mean patient age was 14.6±3.4 years. There were 13 hemivertebrae, three wedged vertebrae, two butterfly vertebrae, three hemivertebrae with butterfly vertebra, eight unsegmented bars, and five multiple complex lesions. The average surgical duration was 219.4±68.8 minutes. The average blood loss was 1,208.4±763.5 mL. Seven patients required allogeneic blood transfusion. The mean hospital stay duration was 6.1±2.5 days. The complication rate was 11.8% (4/34): one patient had severe blood loss, one had rod breakage, and two had distal adding-on. The Cobb angle reduced from 65.9°±17.4° to 36.3°±15.3° (p<0.001) with a correction rate (CR) of 44.8%±17.4%. The regional kyphotic angle decreased from 39.9°±20.5° to 27.5°±13.9° (p=0.001) with a CR of 19.3%±49.6%. Radiographic parameters (radiographic shoulder height, clavicle angle, T1 tilt, cervical axis, pelvic obliquity, coronal balance, and apical vertebral translation) showed significant improvement postoperatively.
Conclusions: SSPPCF was a feasible option for adolescent patients with congenital scoliosis who were skeletally matured.