Percutaneous short-segment pedicle screw placement without fusion in the treatment of thoracolumbar burst fractures: is it effective?: comparative study with open short-segment pedicle screw fixation with posterolateral fusion

Background

Since introduction of the pedicle screw-rod system, short-segment pedicle screw fixation has been widely adopted for thoracolumbar burst fractures (TLBF). Recently, the percutaneous pedicle screw fixation (PPSF) systems have been introduced in spinal surgery; and it has become a popularly used method for the treatment of degenerative spinal disease. However, there are few clinical reports concerning the efficacy of PPSF without fusion in treatment of TLBF. The purpose of this study was to determine the efficacy and safety of short-segment PPSF without fusion in comparison to open short-segment pedicle screw fixation with bony fusion in treatment of TLBF.

Methods

This study included 59 patients, who underwent either percutaneous (n?=?32) or open (n?=?27) short-segment pedicle screw fixation for stabilization of TLBF between December 2003 and October 2009. Radiographs were obtained before surgery, immediately after surgery, and at the final follow-up for assessment of the restoration of the spinal column. For radiologic parameters, Cobb angle, vertebral wedge angle, and vertebral body compression ratio were assessed on a lateral thoracolumbar radiograph. For patient’s pain and functional assessment, the visual analogue scale (VAS), the Frankel grading system, and Low Back Outcome Score (LBOS) were measured. Operation time, and the amount of intraoperative bleeding loss were also evaluated.

Findings

In both groups, regional kyphosis (Cobb angle) showed significant improvement immediately after surgery, which was maintained until the last follow up, compared with preoperative regional kyphosis. Postoperative correction loss showed no significant difference between the two groups at the final follow-up. In the percutaneous surgery group, there were significant declines of intraoperative blood loss, and operation time compared with the open surgery group. Clinical results showed that the percutaneous surgery group had a lower VAS score and a better LBOS at three months and six months after surgery; however, the outcomes were similar in the last follow-up.

Conclusions

Both open and percutaneous short-segment pedicle fixation were safe and effective for treatment of TLBF. Although both groups showed favorable clinical and radiologic outcomes at the final follow-up, PPSF without bone graft provided earlier pain relief and functional improvement, compared with open TPSF with posterolateral bony fusion. Despite several shortcomings in this study, the result suggests that ongoing use of PPSF is recommended for the treatment of TLBF.     

One-stage anterior debridement,bone grafting and posterior instrumentation vs. single posterior debridement,bone grafting,and instrumentation for the treatment of thoracic and lumbar spinal tuberculosis

Purpose

The aim of this study was to compare single posterior debridement, interbody fusion and instrumentation with one-stage anterior debridement, interbody fusion and posterior instrumentation for treating thoracic and lumbar spinal tuberculosis.

Method

From January 2006 to January 2010, we enrolled 115 spinal tuberculosis patients with obvious surgical indications. Overall, 55 patients had vertebral body destruction, accompanied by a flow injection abscess or a unilateral abscess volume greater than 500 ml. The patients underwent one-staged anterior debridement, bone grafting and posterior instrumentation (group A) or single posterior debridement, bone grafting and instrumentation (group B). Clinical and radiographic results for the two groups were analyzed and compared.

Results

Patients were followed 12–36 months (mean 21.3 months), Fusion occurred at 4–12 months (mean 7.8 months). There were significant differences between groups regarding the post-operative kyphosis angle, angle correction and angle correction rate, especially if pathology is present in thoracolumbar and lumbar regions. Operative complications affected five patients in group A, and one patient in group B. A unilateral psoas abscess was observed in three patients 12 months postoperatively. In one of them, interbody fusion did not occur, and there was fixation loosening and interbody absorption. All of them were cured by an anterior operation.

Conclusion

Anterior debridement and bone grafting with posterior instrumentation may not be the best choice for treating patients with spinal tuberculosis. Single posterior debridement/bone grafting/instrumentation for single-segment of thoracic or lumbar spine tuberculosis produced good clinical results, except in patients who had a psoas abscess.     

Anterior debridement and bone grafting with posterior single-segment internal fixation for the treatment of mono-segmental spinal tuberculosis

BackgroundsShort-segment or long-segment fixation is the most commonly used method for treating spinal tuberculosis with damage to a single motor segment (mono-segmental spinal tuberculosis). However, these methods incorporate several of the normal adjacent motor segments surrounding the damaged motor segments during surgery and subsequent healing, leaving them prone to adjacent segment degeneration. A single-segment fixation approach may offer an alternative solution for the surgical treatment of mono-segmental spinal tuberculosis.Patients and methods102 Retrospectively studied patients with mono-segmental spinal tuberculosis were divided into two groups: single-segment (the fixed/fused range was limited to only one damaged motion segment n = 54) and short-segment (the fixed/fused range included both the damaged segment and the normal motion segment located above and below the damaged motion segment, respectively n = 48). Responses to postoperative chemotherapy and changes in the Cobb angle for kyphosis, fusion time, and Frankel grading were recorded. Each patient's quality of life and ability to return to work, as determined by the Oswestry Disability Index (ODI), were also evaluated.ResultsAt the end of the final follow-up, the degree of correction was 12.69 ± 4.56° and 13.44 ± 4.53° for the single-segment and short-segment groups, respectively, with a loss of 1.80 ± 1.19° and 1.60 ± 1.16°, respectively. The differences between the two groups were not significant (P > 0.05). The average bone healing time was 4.4 ± 0.9 months in the single-segment group and 4.4 ± 1.0 months in the short-segment group. The Frankel grade for neurologic function returned to normal in >94% of patients. The ODI was 13.5 ± 2.8 and 14.1 ± 3.7 for the single-segment and short-segment groups, respectively. The rates of improvement were 64.0 ± 5.5% and 65.9 ± 4.9% for the single-segment and short-segment groups, respectively. The differences between the two groups were not significant (P > 0.05).ConclusionAfter bone fusion, single-segment fixation is effective in restoring and maintaining spinal stability and retains normal motion segment more than short-segment fixation approach. Strict adherence to the clinical indications must occur in order to optimize the overall outcome.     

Surgical management for multilevel noncontiguous thoracic spinal tuberculosis by single-stage posterior transforaminal thoracic debridement, limited decompression, interbody fusion, and posterior instrumentation (modified TTIF)

Purpose

Multilevel noncontiguous thoracic spinal tuberculosis has rarely been reported in the literature. We present a retrospective clinical study of 14 patients with multilevel noncontiguous thoracic spinal tuberculosis treated by single-stage posterior transforaminal thoracic debridement, limited decompression, interbody fusion, and posterior instrumentation (modified TTIF) and determine the clinical effectiveness of such surgical treatment for MNTST.

Methods

Fourteen patients with multilevel noncontiguous thoracic spinal tuberculosis were treated with modified TTIF. The mean follow-up was 27.36?±?10.46?months (range 13–42?months). The kyphotic angle ranged from ?2° to 47° before operation, with an average of 19.21°?±?12.63°. The erythrocyte sedimentation rate (ESR) of patients upon admission ranged from 30 to 62?mm/h before operation, with an average of 46.43?±?10.77?mm/h. The Frankel Grade was used to evaluate the neurological deficits.

Results

The average ESR got normal (8.14?±?5.89?mm/h) within 3?months in all patients. The average kyphotic angle decreased to 8.07°?±?6.91° postoperatively. Mean deformity angle was measured as 8.79°?±?7.29° at the last visit. Solid fusion was achieved in all cases. Neurologic status of the 12 patients with preoperative neurologic deficit was 6 with grade D recovered to normal; 2 with grade B, both of them to grade D; 4 with grade C, 2 to grade D, 1 to grade E, and 1 still in grade C.

Conclusions

Modified TTIF can be an effective treatment method of multilevel noncontiguous thoracic spinal tuberculosis.     

Surgical approach and management outcomes for junction tuberculous spondylitis: a retrospective study of 77 patients

Background

Junction tuberculous spondylitis involves the stress transition zone of the spine and has a high risk of progression to kyphosis or paraplegia. Problems still exist with treatment for spinal junction tuberculosis. This study investigated the surgical approach and clinical outcomes of junction spinal tuberculosis.

Methods

From June 1998 to July 2014, 77 patients with tuberculous spondylitis were enrolled. All patients received 2–3?weeks of anti-tuberculous treatment preoperatively; treatment was prolonged for 2–3?months when active pulmonary tuberculosis was present. The patients underwent anterior debridement and were followed up for an average of 29.4?months clinically and radiologically.

Results

The cervicothoracic junction spine (C7-T3) was involved in 15 patients. The thoracolumbar junction spine (T11-L2) was involved in 39 patients. The lumbosacral junction spine (L4-S1) was involved in 23 patients. Two patients with recurrence underwent reoperation; the drugs were adjusted, and all patients achieved bone fusion. The preoperative cervicothoracic and thoracolumbar kyphosis angle and lumbosacral angle were 31.4?±?10.9°, 32.9?±?9.2°, and 19.3?±?3.7°, respectively, and the corresponding postoperative angles were ameliorated significantly to 9.1?±?3.2°, 8.5?±?2.9°, and 30.3?±?2.8°. The preoperative ESR and C-reactive protein level of all patients were 48.1?±?11.3?mm/h and 65.5?±?16.2?mg/L which decreased to 12.3?±?4.3?mm/h and 8.6?±?3.7?mg/L at the final follow-up, respectively. All patients that had neurological symptoms achieved function status improvement at different degrees.

Conclusion

For spinal tuberculosis of spinal junctions, anterior debridement, internal fixation, and fusion can be preferred and achieved. If multiple segment lesions are too long or difficult for operation of anterior internal fixation, combining posterior pedicle screw fixation is appropriate.

     

Biomechanical comparison of different fixation techniques for reconstruction of tibial avulsion fractures of the anterior cruciate ligament

Purpose

The most common fixation techniques for tibial avulsion fractures of the anterior cruciate ligament (ACL) described in the literature are screw and suture fixation. The fixation of these fractures with the TightRope® device might be an alternative. Up to now it has been commonly used in other injuries, such as acromioclavicular joint or syndesmosis ruptures. The purpose of this study was to evaluate the biomechanical properties of different fixation techniques for the reconstruction of tibial avulsion fractures.

Methods

Type III tibial avulsion fractures were simulated in 40 porcine knees. Each specimen was randomly assigned to one of four groups: (1) anterograde screw fixation, (2) suture fixation, (3) TightRope® fixation or (4) control group. The initial displacement, strength to failure and the failure mode were documented.

Results

The maximum load to failure was 1,345?±?155.5 N for the control group, 402.5?±?117.6 N for the TightRope® group, 367?±?115.8 N for the suture group and 311.7?±?120.3 N for the screw group. The maximum load to failure of the control group was significantly larger compared to all other groups. The initial dislocation was 0.28?±?0.09 mm for the control group, 0.55?±?0.26 mm for the TightRope® group, 0.84?±?0.15 mm for the screw group and 1.14?±?0.9 mm for the suture group. The initial dislocation was significantly larger for the suture group compared to the TightRope® and control groups.

Conclusions

The TightRope® fixation shows significantly lower initial displacement compared to the suture group. The TightRope® fixation might be an alternative for the repair of ACL tibial avulsion fractures that can be used arthroscopically.     

Surgical treatment of thoracic spinal tuberculosis with adjacent segments lesion via one-stage transpedicular debridement, posterior instrumentation and combined interbody and posterior fusion, a clinical study

Purpose

To investigate the clinical efficacy and feasibility of one-stage surgical treatment for thoracic spinal tuberculosis with adjacent segments lesion by internal fixation, transpedicular debridement, and combined interbody and posterior fusion via a posterior-only approach.

Materials and methods

Twenty-one patients (thirteen males, eight females) with thoracic tuberculosis whose lesions were confined to two adjacent segments were studied retrospectively. All patients were treated with one-stage surgical treatment by internal fixation, transpedicular debridement, and combined interbody and posterior fusion via a posterior-only approach. The American Spinal Injury Association (ASIA) impairment scale was used to assess neurological function. Thoracic Cobb angle was used to assess thoracic kyphosis. Operating time, blood loss, complications, neurological function, deformity correction and interbody fusion were investigated.

Results

Average mean operating time was 231.4 ± 31.9 min, and evaluated blood loss during operation was 880.2 ± 112.7 ml. All patients were followed up for 22–41 months postoperatively (average 29.8 ± 5.4 months). All patients had significant postoperative improvement in ASIA classification scores. The thoracic kyphotic angles were significantly decreased to 9°–25° postoperatively (average 16.7° ± 4.4°), and at final follow-up were 10°–27°(average 17.7° ± 4.4°). No severe complications or spinal cord injury occurred. The erythrocyte sedimentation rate recovered to normal within 3 months postoperatively in all patients. All patients got bony fusion within 6–9 months after surgery.

Conclusions

One-stage transpedicular debridement, posterior instrumentation and combined interbody and posterior fusion via a posterior-only approach can be an effective and feasible treatment method for thoracic spinal tuberculosis.     

Operative treatment of scoliosis in proximal spinal muscular atrophy: results of 41 patients

Introduction

The early development of progressive scoliosis with pelvic obliquity is the most significant orthopaedic problem for non-ambulatory children with spinal muscular atrophy (SMA).

Patients

24 SMA patients were operated on for scoliosis using the ISOLA^? system and 17 patients using a telescopic rod. The average age at spinal surgery was 12.3?years (6.5?C22.7) in the ISOLA^? group and 6.7?years (4.8?C10.9) in the telescopic rod group.

Results

The Cobb angle was corrected on average from pre-operative 83°(54°?C120°) to post-operative 39°(5°?C70°) in the ISOLA^? group and, respectively, from 62°(28°?C86°) to 18°(0°?C34°) in the telescopic rod group. Mean loss of correction at mean follow-up of 6?years (3?C10) was 6°(0°?C33°) in the ISOLA^? group and at mean follow-up of 8.6?years (3?C12) 13°(0°?C49°) in the telescopic rod group excluding the patients with rod failure. The vital capacity is not worsened by these operations in comparison to the natural course. After telescopic rods were implanted, there were some unsatisfactory results due to crankshaft phenomenon and an increase of pelvic obliquity.

Conclusion

Our recommendation for non-ambulatory SMA patients is to have definitive stabilisation using multisegmental instrumentation, starting from the age of 10 to 12?years.     

Increase in spinal longitudinal length by correction surgery for adolescent idiopathic scoliosis

Purpose

One of the downsides of spinal correction surgery for adolescent idiopathic scoliosis (AIS) is the cessation of spinal longitudinal growth within the fused levels in growing children. However, the surgery itself has the potential to increase spinal longitudinal length by correcting the curvature. The purpose of this study was to evaluate the correlation between curve correction and increased spinal longitudinal length by corrective surgery for AIS.

Methods

This study included 208 consecutive patients (14 male, 194 female) with AIS who underwent posterior or anterior correction and fusion surgeries. Mean age at the time of surgery was 15.7 ± 3.3 years (range 10–20 years). Patients with hyperkyphosis of more than 40° were excluded. All patients had main curves in the thoracic spine (Lenke type 1 or 2). Forty-three patients underwent anterior spinal correction and fusion (ASF) and 164 underwent posterior spinal correction and fusion (PSF). The mean preoperative height was 154.7 ± 6.9 cm (range 133–173 cm). Pre and postoperative PA standing X-ray films were used to measure the Cobb angle and spinal length between the end vertebrae of the main thoracic curve, and between T1 and L5. The patients were divided into ASF and PSF groups, within which correlations between the Cobb angle correction and spinal length increase were evaluated.

Results

In the ASF group, the mean preoperative Cobb angle of the main thoracic curve was 54.9 ± 8.3° (range 41–83°) and it was corrected to 19.7 ± 9.5° (range 0–47°) with a mean correction of 35.2 ± 11.1° (range 10–74°) after surgery. The mean increase in the length of the main thoracic curve was 1.5 ± 4.6 mm (range ?8 to 13 mm), and the mean increase in T1–L5 length was 16.6 ± 7.7 mm (range ?3 to 51 mm). Significant correlation between the correction of the Cobb angle and increase in T1–L5 length was observed, with a correlation coefficient of 0.44. In the PSF group, the mean preoperative Cobb angle of the main thoracic curve was 58.8 ± 11.6° (range 36–107°) and it was corrected to 17.1 ± 7.6° (range 10–49°), with a mean correction of 41.7 ± 10.2° (range 21–73°) after surgery. The mean increase in the length of the main thoracic curve was 14.0 ± 5.2 mm (range 0–42 mm), and the mean increase in T1–L5 length was 32.4 ± 10.8 mm (10–61 mm). Correlation between the correction of the Cobb angle and increase in T1–L5 length was high, with a correlation coefficient of 0.64. The increase in T1–L5 length could be calculated by the following formula based on linear regression analysis: increase in T1–L5 length (mm) = correction of the Cobb angle (º) × 0.77.

Conclusion

Spinal longitudinal length was significantly increased after surgery in both the ASF and PSF groups. Correction of the Cobb angle and increase in T1–L5 length were highly correlated with each other, especially in the PSF group.     

Percutaneous fixation of acetabular fractures: computer-assisted determination of safe zones, angles and lengths for screw insertion

Introduction

Percutaneous retrograde screw fixation for acetabular fractures is a demanding procedure due to the complex anatomy of the pelvis and the varying narrow safe bony corridors. Limited information is available on optimal screw placement and the geometry of safe zones for screw insertion in the pelvis.

Methods

Three-dimensional reconstructions of 50 consecutive CT scans of polytrauma patients (35 males, 15 females) were used to introduce three virtual CAD bolts (representing screws) into the anterior column (superior ramus of the pubic bone), posterior column (the ischial bone) and the supraacetabular region, as performed during percutaneous screw fixation. The three-dimensional (3D) position of these screws was evaluated with a computer software (MIMICS) after virtual optimal insertion. The 3D position, the narrowest zone and the distance to the hip joint of the two columns and the supraacetabular region were defined.

Results

The mean maximal screw length for the three virtual screws measured between 107.4 and 148?±?18.7?mm. The narrowest zone of the pelvic bone (superior pubic ramus) had a width of 9.2?±?2.4?mm. The average distances between the bolts and the hip joint were 3.9 and 19.4?±?7.4?mm. For the anterior column (superior pubic ramus) screw, the mean lateral angle to the sagittal midline plane was 39.0?±?3.2° and the mean posterior angle to the transversal midline plane was 15.1?±?4.0°. The mean supraacetabular screw angles measured 22.4?±?3.4° (medial), 35.3?±?4.6° (cranial) and the mean angles for the ischial screw were 12.0?±?5.4° (posterior) and 18.4?±?4.0° (lateral).

Conclusions

The zones for safe screw positioning are very narrow, making percutaneous screw fixation of the acetabulum a challenging procedure. The predefined angles for the most frequently positioned percutaneous screws may aid in preoperative planning, decrease operative and radiation times and help to increase safe insertion of screws.     

Thoracic curve correction after posterior fusion and instrumentation of structural lumbar curves in patients with adolescent idiopathic scoliosis

Introduction

Spontaneous thoracic curve correction may occur following selective anterior spinal fusion in patients with adolescent idiopathic scoliosis (AIS). However, a few reports have described outcomes in patients following selective posterior fusion. The aim of this retrospective study was to assess curve correction in AIS patients with major lumbar curves and secondary thoracic curves after selective posterior fusion of the major curve.

Methods

The records of 42 AIS patients with major lumbar and minor thoracic curves who had received selective posterior lumbar fusion with segmental pedicle screw fixation were examined. Preoperative and follow-up radiographs were examined and the following were determined: curve flexibility, Cobb angle measurements of the major and minor curves, thoracolumbar/lumbar and thoracic Cobb measurements. Also, thoracolumbar/lumbar to thoracic Cobb ratios were determined. Minimum follow-up was 2?years. Patients were compared with respect to whether final thoracic curve improvement was (group A) or was not (group B) apparent. Improvement was indicated by a final thoracic curve that was less than the preoperative thoracic curve.

Results

Thoracic curve improvement was apparent in 32 of 42 patients after surgery. The mean preoperative thoracic curve in group A was 22.5° and 15.0° at follow-up, while corresponding values in group B were 35.0° and 39.8°. There were no cases in group A and eight cases in group B in which the preoperative thoracic curve was >30°. All patients in group B had preoperative thoracic curves on lateral bending >20°. Thoracic curvature at final follow-up was strongly correlated with preoperative thoracic curvature (r?=?0.911) and thoracic curvature on lateral bending (r?=?0.948).

Conclusions

Selective posterior fusion with segmental pedicle screw fixation in patients with major lumbar AIS resulted in curve correction in the majority of cases. Preoperative thoracic curvature and thoracic curvature on lateral bending were strongly correlated with the final thoracic curvature.     

患椎间短椎弓根螺钉在单节段腰骶椎结核稳定性重建中的临床研究

目的证明后路患椎间短椎弓根螺钉固定治疗单节段腰骶椎结核的可行性,并探讨其适应证及疗效。方法 204例诊断明确、脊柱后凸畸形35°,符合纳入标准的单节段腰、骶椎结核患者,随机分为2组,均先进行后路矫形、内固定手术,同期或二期进行前路彻底病灶清除、椎体间自体髂骨支撑植骨融合术。其中短钉组104例,选用长20~35 mm的短椎弓根钉置于患椎椎弓根。如1个患椎剩余骨质1/3,而另1个患椎剩余骨质1/3,则行短钉、常规螺钉固定。长钉组:常规椎弓根螺钉置于患椎相邻的正常椎骨中,固定范围跨越患椎上、下各1个正常间隙。所有患者均采用四联化疗方案。结果 2组患者平均随访62.1个月。术后均无严重并发症发生,末次随访时,所有患者均治愈,无内固定松动及断裂现象。植骨平均愈合时间,短钉组4.3个月,长钉组4.6个月,Cobb角矫正度及丢失率2组分别为13.26°±3.76°,6.22%和16.35°±2.63°,5.24%,2组比较差异无统计学意义(P0.05),组内术前术后比较差异有统计学意义(P0.05)。血沉与C反应蛋白的术前术后差异无统计学意义。2组患者术后2年生活、工作基本恢复正常。短钉组患者术后功能恢复较长钉组好。结论腰、骶椎结核后路患椎间短椎弓根钉固定、前路病灶彻底清除术具有仅融合、固定病变节段,保留相邻正常的脊柱运动单元功能,术后脊柱功能恢复好等优点,具有很高的临床应用价值。     

Surgical management by one-stage posterior transforaminal lumbar debridement, interbody fusion, and posterior instrumentation for lumbo-sacral tuberculosis in the aged

Purpose

To evaluate the clinical study efficacy and feasibility of 17 aged patients with lumbo-sacral tuberculosis treated by one-stage posterior transforaminal lumbar debridement, interbody fusion, and posterior instrumentation.

Methods

17 aged patients who suffered from lumbo-sacral tuberculosis were admitted into our hospital between March 2003 and October 2010. All of them were treated by one-stage posterior transforaminal lumbar debridement, interbody fusion, and posterior instrumentation. Then the clinical efficacy with statistical analysis was evaluated based on the materials on the lumbo-sacral angle, neurological status that was recorded by Frankel grade system, and erythrocyte sedimentation rate (ESR), which were collected at certain time.

Results

The average follow-up period was 47.5?±?17.1?months (17?C71?months), In the 17 cases, no postoperative complications related to instrumentation occurred and neurologic function was improved in various degrees. The mean preoperative lumbo-sacral angle was 20.5°?±?1.7° (range 18.0°?C23.0°). The lumbo-sacral angle became 29.1°?±?1.5° (range 26.4°?C31.0°) postoperatively. The average pretreatment ESR was 57.4?±?16.8?mm/h (33?C95?mm/h), which got normal (9.2?±?3.1?mm/h) within 3?months in all patients. All patients got bony fusion within 6?C8?months after surgery.

Conclusions

One-stage posterior transforaminal lumbar debridement, interbody fusion, and posterior instrumentation can be an effective treatment method for the treatment of lumbo-sacral tuberculosis in the aged patients.     

Reattachment of the endopelvic fascia to the apex during anterior colporrhaphy: does the type of suture matter?

Introduction and hypothesis

We aimed to determine if the use of permanent suture for the apical fixation during traditional anterior colporrhaphy results in improved outcomes compared to delayed absorbable suture.

Methods

A retrospective case-control study was performed in patients who underwent traditional non-grafted anterior colporrhaphy with reattachment of the anterior endopelvic fascia to the apex/cervix comparing permanent (group 1) or absorbable suture (group 2). Patients were matched based on age, body mass index, and presenting stage of prolapse. The primary outcome assessed was anterior wall vaginal prolapse recurrence defined as Pelvic Organ Prolapse Quantification (POP-Q) points Aa or Ba?≥??1 cm. Secondary outcome measures included overall prolapse stage, subjective reporting of satisfaction, and any healing abnormalities or complications resulting from suture type.

Results

A total of 230 patients were reviewed (80 in group 1 and 150 in group 2) and median follow-up was 52 (24–174) weeks. A statistically significant improvement in anterior wall anatomy was seen in group 1 compared to group 2 [(Aa ?2.70?±?0.6 cm vs ?2.5?±?0.75 cm, p?=?0.02) and Ba (?2.68?±?0.65 cm vs ?2.51?±?0.73 cm, p?=?0.03), respectively]. Comparing prolapse stage, there were no observed differences between the groups. Exposure of the permanent suture occurred in 12 patients (15 %) and 5 (6.5 %) required suture trimming to treat the exposure.

Conclusions

Reattachment of endopelvic fascia to the apex at the time of anterior colporrhaphy results in low recurrence rates. Use of permanent suture for apical fixation is associated with improved anatomic correction at the expense of increased suture exposures.     

The biomechanical characteristics of arthroscopic tibial inlay techniques for posterior cruciate ligament reconstruction: in vitro comparison of tibial graft tunnel placement

Purpose

The hypothesis of the present study was that the biomechanical properties of arthroscopic tibial inlay procedures depend on tibial graft bone block position.

Methods

Five paired fresh-frozen human cadaveric knee specimens were randomized to a reconstruction with quadriceps tendon placing the replicated footprint either to the more proximal margin of the remnants of the anatomical PCL fibrous attachments (group A) or to the distal margin of the anatomical PCL fibrous attachments at the edge of the posterior tibial facet to the posterior tibial cortex in level with the previous physis line (group B). The relative graft-tibia motions, post cycling pull-out failure load and failure properties of the tibia-graft fixation were measured. Cyclic displacement at 5, 500 and 1,000 cycles, stiffness and yield strength were calculated.

Results

The cyclic displacement at 5, 500 and 1,000 cycles measured consistently more in group A without statistically significant difference (4.11?±?1.37, 7.73?±?2.73 and 8.18?±?2.75 mm versus 2.81?±?1.33, 6.01?±?2.37 and 6.46?±?2.37 mm). Mean ultimate load to failure (564.6?±?212.3) and yield strength (500.2?±?185.9 N) were significantly higher in group B (p?Conclusion Replicating the anatomical PCL footprint at the posterior edge of the posterior tibial facet yields higher pull-out strength and less cycling loading displacement compared to a tunnel position at the centre of the posterior tibial facet.     

Superior border of the arcuate line: Three dimension reconstruction and digital measurements of the fixation route for pelvic and acetabular fractures

Purpose

To obtain a series of parameters describing the shape and bone thickness of the fixation route along the superior border of the arcuate line, so as to provide references for pelvic and acetabular surgery and design pelvic anatomic internal fixators.

Method

A total of 175 complete pelvic computed tomography (CT) scans of normal adult pelvises were collected. Each person’s CT scans were reconstructed to create a three-dimensional pelvic model. A curve of the fixation route was delineated and divided into 11 equal parts. The total length of the curve, the radius of curvature, and the bone thickness at each decile point were all measured. The position of the pelvic inlet, the anterior and posterior sagittal diameter were measured.

Results

The radius of curvature at each decile point were 29.18?±?15.53, 55.27?±?29.48, 43.04?±?14.42, 59.62?±?21.02, 91.67?±?52.01, 78.9?±?38.66, 75.76?±?25.87, 61.75?±?16.68, 54.62?±?14.88, and 43.61?±?19.10 mm, respectively. The anterior and posterior sagittal diameter of the pelvic inlet was 66.01?±?9.15 and 41.36?±?8.19 mm, respectively. For all groups divided by the ratio of the posterior and the anterior sagittal diameter, the decile points 1, 3, and 10 had smaller radii of curvature than the before and after points, respectively.

Conclusions

The curve of the fixation route along superior border of arcuate line has a relatively greater bending degree at the pubic tubercle, iliopubic eminence and close to the sacroiliac joint. With the transition of the pelvic inlet shape from android to gynecoid and platypelloid type, the bone surface at the iliopubic eminence becomes flatter. Pelvic and acetabular surgery could be more accurate by referring to the previous key bending points and the change of the pelvic inlet shape.     

Evaluation of a knitted polytetrafluoroethylene mesh placed intraperitoneally in a New Zealand white rabbit model

Background

The intraperitoneal application of surgical mesh remains a controversial issue because of possible complications, especially adhesion and fistula formation. This study aimed to assess the potential of a knitted polytetrafluoroethylene (PTFE) mesh for intraabdominal implantation.

Methods

Twenty-eight 5?×?5?cm samples of knitted macroporous PTFE mesh and light-weight polypropylene mesh (LW-PP) were implanted intraperitoneally in 14 New Zealand white rabbits in a randomized manner and fixed using eight polypropylene stitches. After 90?days, the adhesion formation, adhesion score, shrinkage, strength of fixation to the abdominal wall, and histologic biocompatibility were assessed.

Results

No intraoperative or anesthesia-related complications or mesh infection were recorded. The average area covered by adhesions was 4.7?±?7.2% for the PTFE and 36.4?±?36.1% for the LW-PP. The median adhesion score was 0 for the PTFE and 8 for the LW-PP. Shrinkage was 36.9?±?12.9% for the PTFE mesh and 12.6?±?8.72% for the LW-PP. The mesh-to-abdominal wall fixation strength was almost the same for both materials (PTFE 3.6?±?1.9 vs. LW-PP 3.6?±?2.9). The inflammatory cell count was almost the same for the two groups, with no statistically significant difference. The width of the inner granuloma was equal (PTFE 10.5?±?0.9 vs. LW-PP 11.1?±?0.9). The outer granuloma was reduced significantly in the PTFE group (PTFE 23.0?±?2.1 vs. LW-PP 33.6?±?7.9). One of the animals in the PTFE group died on postoperative day 12 because of ileus. The reason was an adhesion of the small intestine to the polypropylene fixation stitch, which caused small intestine strangulation.

Conclusions

The knitted PTFE mesh induces fewer intraperitoneal adhesions of lower density than the light-weight polypropylene mesh. The strength of the knitted PTFE mesh fixation to the abdominal wall is comparable with that of the light-weight polypropylene mesh, but the shrinkage is greater. The biocompatibility of the knitted PTFE mesh is comparable with that of the light-weight polypropylene implant.     

Internal fixation with percutaneous kyphoplasty compared with simple percutaneous kyphoplasty for thoracolumbar burst fractures in elderly patients: a prospective randomized controlled trial

Purpose

The impact of percutaneous internal fixation as a supplement to percutaneous kyphoplasty (PKP) for the management of thoracolumbar burst fractures in elderly patients is unclear. We conducted a clinical controlled trial to investigate the effect and outcomes of this technique in such patients.

Methods

Forty-three patients over 65 years old with thoracolumbar burst fractures without nerve injuries were enrolled. They were randomly assigned to treatment with simple PKP (control group, n = 22) or percutaneous short-segment pedicle screw internal fixation with PKP (treatment group, n = 21). The patients were followed for at least 2 years postoperatively and were assessed with regard to clinical and radiological outcomes. Clinical outcomes were evaluated mainly with use of visual analog scale (VAS) for pain and the Oswestry Disability Index (ODI) questionnaire. Radiological outcomes were assessed mainly on the basis of Cobb kyphosis angle and loss of kyphosis correction.

Results

There were no significant differences between the two groups with regard to preoperative indices. The treatment group had better VAS scores and greater postoperative improvement on the ODI compared with the control group (P < 0.05). Postoperative kyphosis angle correction in the treatment group was superior to that in the control group, and loss of correction postoperatively was significantly less (P < 0.05). In the control group, two patients suffered refractures of the injured vertebra postoperatively and one had a fracture in the adjacent vertebra. No postoperative complications needing management were noted in either group.

Conclusions

Compared with simple PKP, percutaneous internal fixation with PKP is a valuable surgical option for the treatment of selected elderly patients with thoracolumbar burst fractures.     

Angulated locking plate in periprosthetic proximal femur fractures: biomechanical testing of a new prototype plate

Introduction

To improve proximal plate fixation of periprosthetic femur fractures, a prototype locking plate with proximal posterior angulated screw positioning was developed and biomechanically tested.

Methods

Twelve fresh frozen, bone mineral density matched human femora, instrumented with cemented hip endoprosthesis were osteotomized simulating a Vancouver B1 fracture. Specimens were fixed proximally with monocortical (LCP) or angulated bicortical (A-LCP) head-locking screws. Biomechanical testing comprised quasi-static axial bending and torsion and cyclic axial loading until catastrophic failure with motion tracking.

Results

Axial bending and torsional stiffness of the A-LCP construct were (1,633?N/mm?±?548 standard deviation (SD); 0.75?Nm/deg?±?0.23?SD) at the beginning and (1,368?N/mm?±?650?SD; 0.67?Nm/deg?±?0.25?SD) after 10,000 cycles compared to the LCP construct (1,402?N/mm?±?272?SD; 0.54?Nm/deg?±?0.19?SD) at the beginning and (1,029?N/mm?±?387?SD; 0.45?Nm/deg?±?0.15) after 10,000 cycles. Relative movements for medial bending and axial translation differed significantly between the constructs after 5,000 cycles (A-LCP 2.09°?±?0.57?SD; LCP 5.02°?±?4.04?SD; p?=?0.02; A-LCP 1.25?mm?±?0.33?SD; LCP 2.81?mm?±?2.32?SD; p?=?0.02) and after 15,000 cycles (A-LCP 2.96°?±?0.70; LCP 6.52°?±?2.31; p?=?0.01; A-LCP 1.68?mm?±?0.32; LCP 3.14?mm?±?0.68; p?=?0.01). Cycles to failure (criterion 2?mm axial translation) differed significantly between A-LCP (15,500?±?2,828?SD) and LCP construct (5,417?±?7,236?SD), p?=?0.03.

Conclusion

Bicortical angulated screw positioning showed less interfragmentary osteotomy movement and improves osteosynthesis in periprosthetic fractures.     

Unilateral versus bilateral pedicle screw fixation in short-segment lumbar spinal fusion: a meta-analysis of randomised controlled trials

Objective

We performed this meta-analysis of randomised controlled trials to compare the efficacy and safety of unilateral with bilateral fixation in short-segment lumbar spinal fusion.

Methods

Predefined terms were used to search electronic databases to identify relevant research. Randomised controlled trials (RCTs) published in English and Chinese during 1990–2015 investigating efficacy and safety of unilateral and bilateral fixation in short-segment lumbar spinal fusion were included. Data of fusion rate, complications, visual analogue scale (VAS), Oswestry Disability Index (ODI), estimated blood loss (EBL) and length of hospital stay were extracted and analysed. Two reviewers independently searched information sources, selected eligible research, analysed data and evaluated risk of bias.

Results

Eleven RCTs comprising 756 participants were analysed. There was no significant difference in fusion rate, device-related complication, ODI, VAS and length of hospital stay between bilateral and unilateral groups. The unilateral group had the obvious advantage of reduced blood loss [mean difference (MD)??143.57, 95 % confidence interval (Cl) -206.61 to -80.54, P?<?0.0001) and operation time (MD -52.72, 95 % Cl -73.58 to -31.87, P?<?0.00001).

Conclusion

Unilateral pedicle screw fixation is equally as effective as bilateral pedicle screw fixation in short-segment lumbar spinal fusion and may reduce operation time and blood loss.