Rheumatoid vertical and subaxial subluxation can be prevented by atlantoaxial posterior screw fixation

Purpose

Literature has described a risk for subsequent vertical subluxation (VS) and subaxial subluxation (SAS) following atlantoaxial subluxation in rheumatoid patients; however, the interaction of each subluxation and the radiographic findings for atlantoaxial fixation has not been described. The purpose of this study was to evaluate the effects of two different posterior atlantoaxial screw fixation on the development of subluxation in patients with rheumatoid atlantoaxial subluxation.

Methods

Between 1996 and 2006, rheumatoid patients treated with transarticular fixation and posterior wiring (TA) or C1 lateral mass–C2 pedicle screw fixations (SR) in the Nagoya Spine Group hospitals, a multicenter cooperative study group, were included in this study. VS, SAS, craniocervical sagittal alignment, and range of motion (ROM) at the atlantoaxial adjacent segments were investigated to determine whether posterior atlantoaxial screw fixation is a prophylactic or a risk factor for the development of VS and SAS.

Results

The mean follow-up was 7.2 years (4–12). No statistically significant difference was observed among the patients treated with either of the procedure during the follow-up period. Of 34 patients who underwent posterior atlantoaxial screw fixation, SAS was observed in 26.5 % during the follow-up period; however, VS was not observed. Postoperative C2–7 angle, and Oc–C1 and C2–3 ROM were significantly different between patients with and without postoperative SAS. The incidence of SAS was 38.9 % for TA and 12.5 % for SR; statistically significant differences were observed in the postoperative C1–2 and C2–7 angles, and C2–3 ROM.

Conclusions

Atlantoaxial posterior screw fixation may be an appropriate prophylactic intervention for VS and SAS if the atlantoaxial joint develops bony fusion following physiological alignment. Compared to TA, SR provided optimal atlantoaxial angle and prevented lower adjacent segment degeneration, thereby reducing SAS.     

Anterior C3 corpectomy and fusion for complex Hangman’s fractures

Purpose

The aim of this study was to assess the effectiveness and feasibility of anterior C3 corpectomy and fusion with screw-plate fixation of C2–4 for the treatment of Hangman’s fracture in which spinal cord compression comes from the posterosuperior part of C3 vertebral body and the intervertebral disc injury at the C2–3 level.

Methods

From August 2000 to December 2005, 11 patients (eight males and three females) with traumatic spondylolisthesis of the axis underwent the above surgery. Neurological status was evaluated by the Japanese Orthopaedic Association Score (JOA score). The fusion of the graft, healing of the fracture, and range of motion of the whole cervical spine were examined according to X-ray imaging.

Results

No patient received blood transfusion. There was no deterioration of the neurological function in any case postoperatively. The mean JOA score was significantly improved from 9.1 ± 2.3 preoperatively to 14.8 ± 1.2 at the 12-month postoperative visit. All patients were relieved of axial pain. Imaging evaluation confirmed a high fusion rate and healing rate in all patients. No patient complained of limited mobility of the cervical spine in flexion, extension and rotation. No graft or plate-related complication was observed in any patients during the whole follow-up period. The only postoperative complication was trouble in swallowing liquids in two cases which resolved three months after surgery without any treatment.

Conclusions

Anterior C3 corpectomy and fusion may prove to be safe and applicable for the treatment of complex Hangman’s fractures.     

Axial Lumbosacral Interbody Fusion Appears Safe as a Method to Obtain Lumbosacral Arthrodesis Distal to Long Fusion Constructs

Background

Current methods to achieve lumbosacral interbody fusion have been complicated by approach-related morbidity, nerve root or cauda equina injury, or difficulty in implanting a large lordotic graft posteriorly. There is little information in the literature evaluating the presacral axial approach to the lumbosacral disc space.

Questions/Purposes

What are the short-term clinical and radiographic outcomes in patients undergoing axial lumbosacral interbody fixation and fusion at the end of long fusion constructs using the AxiaLIF implant (Trans1 Inc., Wilmington, NC, USA)? Furthermore, what complications are associated with this procedure?

Patients and Methods

We performed a retrospective evaluation of nine patients who underwent presacral axial lumbosacral interbody fixation and fusion at the end of long fusion constructs using the AxiaLIF implant. Preoperative diagnoses included adjacent segment degeneration below a long fusion construct for adult scoliosis and progressive sagittal plane deformity.

Results

There were two pseudoarthroses, one at L4–5 and one at L5–S1. No major complications occurred. There were no significant differences in coronal or sagittal plane alignment at the time periods measured. There was no significant difference in implant position between immediate postoperative and final follow-up periods. There were significant postoperative improvements in Scoliosis Research Society-22 scores, specifically in the pain, self-image, and satisfaction with management domains.

Conclusions

The axial lumbosacral interbody fusion is a minimally invasive and safe method to obtain lumbosacral fixation and arthrodesis distal to a long fusion construct. Longer follow-up of larger numbers of patients are needed prior to recommending this procedure as a routine method to fuse L4–5 or L5–S1.     

Bilateral decompression using a unilateral pedicle construct for lumbar stenosis

Purpose

To determine the effectiveness of bilateral decompression via a unilateral approach using unilateral pedicle screw fixation for two-level lumbar stenosis with instability.

Methods

Between October 2006 and October 2010, 98 patients (61 men and 37 women) who had reached the three-year follow-up interval were treated with unilateral pedicle screw fixation at the authors’ institution. All patients underwent two-level transforaminal lumbar interbody fusion (TLIF), and the mean age was 59.6 years (range, 40–72). Visual analog scale (VAS) scores and Oswestry Disability Index (ODI) were used to assess the pre-operative and postoperative clinical results. Fusion status, the disc space height, and the whole lumbar lordotic angle were analysed for the radiological evaluation.

Results

The ODI scores decreased significantly in both early and late follow-up evaluations and the visual analog scale (VAS) score demonstrated significant improvement in late follow-up (P < 0.01). The disc space height (P < 0.05) and the whole lumbar lordotic angle (P < 0.05) were increased at the final follow-up. Successful fusion was achieved in all patients.

Conclusion

Bilateral decompression via a unilateral approach using unilateral pedicle screw fixation for two-level lumbar stenosis with instability, which can maintain the lumbar lordosis and the disc space height, is an effective and less invasive method than with bilateral constructs.     

Odontoid fractures: A retrospective analysis of 53 cases

Background:

The management of odontoid fracture has evolved but controversy persists as to the best method for Type II odontoid fractures with or without atlantoaxial (AA) instability. The anterior odontoid screw fixation can be associated with significant morbidity while delayed odontoid screw fixation has shown to be associated with reasonable good fusion rates. We conducted a retrospective analysis to evaluate the outcome of a trial of conservative management in type II odontoid fractures without atlantoaxial instability (Group A) followed by delayed odontoid screw fixation in cases in which fusion was not achieved by conservative treatment. The outcome of type II odontoid fracture with AA subluxation (Group B) was also analysed where closed reduction on traction could be achieved and in those atlantoaxial subluxations that were irreducible an intraoperative reduction was done.

Materials and Methods:

A retrospective evaluation of 53 cases of odontoid fractures treated over a 9-year period is being reported. All odontoid fractures without AA instability (n=29) were initially managed conservatively. Three patients who did not achieve union with conservative management were treated with delayed anterior screw fixation. Twenty-four cases of odontoid fractures were associated with AA instability; 17 of them could be reduced with skeletal traction and were managed with posterior fusion and fixation. Of the seven cases that were irreducible, the initial three cases were treated by odontoid excision followed by posterior fusion and fixation; however, in the later four cases, intra operative reduction was achieved by a manipulation procedure, and posterior fusion and fixation was performed.

Results:

Twenty-six of 29 cases of odontoid fracture without AA instability achieved fracture union with conservative management whereas the remaining three patients achieved union following delayed anterior odontoid screw fixation. 17 out of 24 odontoid fracture with atlantoaxial dislocation could be reduced on traction and these patients underwent posterior fusion and fixation. Optimal or near optimal reduction was achieved by on table manipulation in four cases which were irreducible with skeletal traction. Atlantoaxial stability was achieved in all cases. All cases were noted to be stable on evaluation with x-rays at six months.

Conclusions:

The initial conservative management and use of odontoid screw fixation only in cases where conservative management for 6–12 weeks has failed to provide fracture union have shown good outcome in type II odontoid fracture without AA instability rates. Intraoperative manipulation and reduction in patients where AA subluxation failed to reduce on skeletal traction followed by posterior fusion obviates the need for transoral odontoid excision.     

Temporary occipito-cervical stabilization of a unilateral occipital condyle fracture

IntroductionInjuries of the occipital condyles are rare. While the majority of occipital condyle fractures can be treated conservatively, surgery is recommended in craniocervical misalignment and instability. Open reduction and temporary occipito-cervical stabilization might be an alternative to fusion or halo treatment.

Materials and methods

This Grand Round case presentation describes temporary C0–C3 stabilization in a 29-year-old man who was involved in a car accident. Radiological examination revealed a rotational burst fracture (type AO C3.1) of C7, and a slight displaced right occipital condyle fracture (Anderson/Montesano type III) with rotational misalignment of the C0–C2 complex.

Results

The C7 fracture was stabilized and fused from anterior and posterior. The occipital condyle fracture was reduced and temporarily stabilized from C0–C3 from posterior. Bony healing occurred after 6 months and consequently the internal fixator was removed to preserve upper cervical mobility.     

Anterior cruciate ligament deficiency leads to early instability of scaffold for cartilage regeneration: a controlled laboratory ex-vivo study

Purpose

The affect of anterior cruciate ligament (ACL) integrity on the early postoperative stability of a collagen type-I gel scaffold was investigated. The value of fibrin glue for graft fixation in ACL deficient porcine knees over a simulated early postoperative period was also studied.

Methods

Full-thickness articular cartilage defects (11 × 6 mm) were created on the medial femoral condyle of 80 porcine knees. The ACL was left intact or completely transected in each of 40 knees. Gel plugs were tested in each group: press-fitting only in 20 specimens and press-fitting plus fibrin glue in 20 specimens. Each knee underwent 2,000 cycles in a validated ex-vivo continuous passive motion model.

Results

Press-fit-only fixation grafts in knee specimens with an intact ACL showed significantly superior stability than that in ACL deficient knees (p = 0.01). In ACL deficient knees, grafts fixed with press-fitting plus fibrin glue showed significantly superior stability than those using press-fit only fixation (p = 0.01). Press-fitting plus fibrin glue fixation showed no significant differences in worn surface area between knee specimens with intact and deficient ACL.

Conclusions

ACL deficiency led to early scaffold instability in an ex-vivo porcine knee model. Fibrin glue in ACL deficient knees led to additional graft stability. These findings indicated that cartilage regenerative techniques may give optimum results in ACL intact knees.     

Does atlantoaxial dislocation influence the subaxial cervical spine?

Introduction

Previous studies have reported that the alignments of the occipital-cervical and subaxial spine were closely interrelated in asymptomatic individuals; however, none have focused on a population with atlantoaxial dislocation.

Material and methods

From 2007 to 2011, 298 patients with atlantoaxial dislocation and atlas occipitalization were studied. Angles formed between Occiput-C2 and C2–C7 were measured. The relationship between the alignment of the occipital-cervical junction and the subaxial cervical spine was evaluated.

Results

The range of values for the angles measured was as followed: the Occiput-C2 angles were −35.2° to 44.8°, and the C2–C7 angles were −17.4° to 77.8°. Statistically significant negative correlations were observed between the Occiput-C2 and C2–C7 angles.

Conclusion

Anterior dislocations of the atlas are associated with diminished lordosis or even kyphosis of the occipital-cervical junction, and result in compensatory hyperlordosis of the subaxial cervical spine, collectively presenting as a “swan neck” deformity. Atlantoaxial dislocation may influence the global cervical alignment.     

Efficacy of interspinous process lumbar fusion with recombinant human bone morphogenetic protein-2 delivered with a synthetic polymer and β-tricalcium phosphate in a rabbit model

Introduction

As a powerful bone-inducing cytokine, rhBMP-2 has been used as a bone graft substitute in combination with animal-derived collagen to achieve interbody or posterolateral spinal fusion. Successful interspinous process fusion using rhBMP-2 in combination with synthetic carrier materials would offer a safe, minimally invasive spinal fusion option for the treatment of spinal disorders. The aims of the present study were to achieve interspinous process fusion by implanting rhBMP-2-retaining degradable material instead of bone grafting and to evaluate efficacy for vertebral stabilization.

Materials and methods

A polymer gel (200 mg), β-tricalcium phosphate powder (400 mg), and rhBMP-2 (0, 30, 60 or 120 μg) were mixed to generate a plastic implant, which was then placed during surgery to bridge the L5–6 interspinous processes of 58 rabbits. Control animals received implants either without rhBMP-2 or with autogenous bone chips from the iliac crest. L5–6 vertebrae were recovered 8 weeks postoperatively. Interspinous process fusion was evaluated by radiography, biomechanical bending test, intradiscal pressure (IDP) measurement, and histology.

Results

In bending tests, strength of fusion was significantly greater in BMP60 and BMP120 groups than in sham, BMP0, BMP30 or autogenous bone groups. IDP at L5–6 was significantly reduced in BMP60 and BMP120 groups compared to sham, BMP0, BMP30, and autograft groups. Histologically, coronal sections of the fusion mass showed a bone mass bridging both spinous processes.

Conclusion

Solid interspinous process fusion was achieved in rabbit models by 8 weeks after implanting the biodegradable bone-inducing material. These results suggest a potential new less-invasive option without bone grafting for the treatment of lumbar disorders.     

Improved outcomes after anterior cruciate ligament reconstruction with quadrupled hamstring autografts and additional bone plug augmentation at five year follow-up

Purpose

Hybrid fixation has been proposed to improve outcomes of anterior cruciate ligament (ACL) reconstructions. This study evaluated midterm outcomes after transfemoral graft fixation using either a conventional or a modified technique using additional bone plug augmentation (BPA) of the femoral tunnel aperture.

Methods

Seventy-one consecutive patients undergoing ACL reconstruction using a quadrupled hamstring autograft with transfemoral graft fixation and tibial interference screw fixation were included. Of these, 56 patients could be followed up 61 months (range 52–69 months) after ACL reconstruction both clinically and by magnetic resonance imaging (group A, conventional technique, n = 34; group B, modified technique, n = 22). Anteroposterior (AP) laxity measurements and International Knee Documentation Committee (IKDC), Lysholm and Tegner activity scoring were performed, while imaging included assessment of bone tunnel diameters, graft condition and graft filling at the femoral bone tunnel aperture.

Results

Patients with additional BPA had a significantly higher degree of graft filling at the femoral bone tunnel aperture (p = .0135) and ‘healthier’ grafts (p = .0495). They also tended to display less AP laxity difference in terms of mean differences and total patient numbers. Lysholm, IKDC and Tegner activity index scores and bone tunnel diameters were not significantly different.

Conclusions

Additional BPA is an easy-to-perform, cheap and safe manoeuvre, which has the capacity to improve morphological and clinical outcomes at five year follow-up. However, femoral tunnel widening is unaffected by additional BPA.     

Ulnar variance as a predictor of persistent instability following Galeazzi fracture-dislocations

Background

We investigated the radiographic parameters that may predict distal radial ulnar joint (DRUJ) instability in surgically treated radial shaft fractures. In our clinical experience, there are no previously reported radiographic parameters that are universally predictive of DRUJ instability following radial shaft fracture.

Materials and methods

Fifty consecutive patients, ages 20–79 years, with unilateral radial shaft fractures and possible associated DRUJ injury were retrospectively identified over a 5-year period. Distance from radial carpal joint (RCJ) to fracture proportional to radial shaft length, ulnar variance, and ulnar styloid fractures were correlated with DRUJ instability after surgical treatment.

Results

Twenty patients had persistent DRUJ incongruence/instability following fracture fixation. As a proportion of radial length, the distance from the RCJ to the fracture line did not significantly differ between those with persistent DRUJ instability and those without (p = 0.34). The average initial ulnar variance was 5.5 mm (range 2–12 mm, SD = 3.2) in patients with DRUJ instability and 3.8 mm (range 0–11 mm, SD = 3.5) in patients without. Only 4/20 patients (20 %) with DRUJ instability had normal ulnar variance (−2 to +2 mm) versus 15/30 (50 %) patients without (p = 0.041).

Conclusion

In the setting of a radial shaft fracture, ulnar variance greater or less than 2 mm was associated with a greater likelihood of DRUJ incongruence/instability following fracture fixation.     

SPECT/CT tracer uptake is influenced by tunnel orientation and position of the femoral and tibial ACL graft insertion site

Purpose

SPECT/CT is a hybrid imaging modality, which combines a 3D scintigraphy (SPECT) and a conventional computerised tomography (CT). SPECT/CT allows accurate anatomical localisation of metabolic tracer activity. It allows the correlation of surgical factors such as tunnel position and orientation with mechanical alignment, clinical outcome and biological factors. The purpose of this study was to investigate whether the SPECT/CT tracer uptake (intensity and distribution) correlates with the stability and laxity of the knee joint and the position and orientation of the tibial and femoral tunnels in patients after anterior cruciate ligament (ACL) reconstruction.

Methods

A consecutive series of knees (n = 66), with symptoms of pain and/or instability after ACL reconstruction were prospectively evaluated using clinical examination and 99mTc-HDP-SPECT/CT. Clinical laxity testing was performed using the Rolimeter (Ormed, Freiburg, Germany) including Lachman testing (0–2 mm, 3–5 mm, 6–10 mm, >10 mm), anterior drawer test (0–2 mm, 3–5 mm, 6–10 mm, >10 mm), pivot shift test (positive versus negative) and patient-based subjective instability (yes versus no).For analysis of SPECT/CT tracer uptake a previously validated SPECT/CT localisation scheme consisting of 17 tibial, nine femoral and four patellar regions on standardised axial, coronal, and sagittal slices was used. The tracer activity on SPECT/CT was localised and recorded using a 3D volumetric and quantitative analysis software.Mean, standard deviation, minimum and maximum of grading for each area of the localisation scheme were recorded. The position and orientation of the tibial and femoral tunnel was assessed using a previously published method on 3D-CT.

Results

Correlation of instability, pivot shift as well as clinical laxity testing with 99mTc-HDP-SPECT/CT tracer uptake intensity and distribution showed no significant correlation. 99mTc-HDP-SPECT/CT tracer uptake correlated significantly with the position and orientation of the ACL graft. A more horizontal femoral graft position showed significantly increased tracer uptake within the superior and posterior femoral regions. A more posteriorly-placed femoral insertion site showed significantly more tracer uptake within the femoral and tibial tunnel regions. A more vertical or a less medial tibial tunnel orientation showed significant increased uptake within the tibial and femoral tunnel regions. A more anterior tibial tunnel position showed significantly more tracer uptake in the femoral and tibial tunnel regions as well as the entire tibiofemoral joint.

Conclusions

SPECT/CT tracer uptake intensity and distribution showed a significant correlation with the femoral and tibial tunnel position and orientation in patients with symptomatic knees after ACL reconstruction. No correlation was found with stability or clinical laxity. SPECT/CT tracer uptake distribution has the potential to give us important information on joint homeostasis and remodelling after ACL reconstruction. It might help to predict ACL graft failure and improve our surgical ACL reconstruction technique in finding the optimal tunnel and graft position and orientation.     

Risk of graft fracture after dorso-ventral thoraco-lumbar spondylodesis: is there a correlation with graft size?

Study design

Retrospective clinical study in patients with dorso-ventral thoraco-lumbar spondylodesis.

Objective

To investigate whether the ratio between graft cross sectional area and the surface area of the adjacent endplates has any effect on the midterm stability of the spondylodesis.

Summary of background data

Dorso-ventral spondylodesis in the region of the thoraco-lumbar spine is one of the most frequent operations in orthopaedic surgery. Anterior stabilization with autologous iliac crest graft currently is a standard approach in many hospitals. Although numerous recommendations are given how to perform this technique, no clinical advice is available with regard to minimum graft size.

Methods

Sixty-four-slice CT-scans were obtained from 82 patients 4–12 months after posterior spondylodesis with anterior implantation of iliac crest graft and stabilization with an internal fixator. The scans were analyzed using image analysis software. First, the cross sectional area of the graft was calculated and then the surface area of the adjacent endplates. The ratio between graft cross sectional area and endplate surface area was then calculated from these two values. The grafts were then evaluated in sagittal reconstruction for signs of fracture.

Results

The probability for graft fracture in autologous tricortical grafts was >0.1% (p < 0.001) if the graft cross sectional area exceeded 23.9% of the surface area of the adjacent endplates. Patients with lower ratio values had a higher fracture risk and below a value of 10% all grafts fractured.

Conclusion

The relationship between graft cross sectional area and adjacent endplate area has an important effect on graft midterm stability in ventral spondylodesis of the thoraco-lumbar spine. In our opinion, the risk of graft fractures in dorso-ventral spondylodesis can be reduced by implantation of an appropriately sized graft without any additional procedures or instrumentation.     

Anterior decompression with single segmental spinal interbody fusion for Denis type B thoracolumbar burst fracture: a midterm follow-up study

Purpose

Our goal was to observe the midterm results of a case series of Denis type B thoracolumbar burst fracture treated with anterior decompression with single segmental spinal Interbody fusion.

Methods

Twenty patients with Denis type B thoracolumbar burst fractures underwent anterior decompression with single segmental spinal Interbody fusion. They underwent clinical and radiologic follow-up for at least three years after the surgery.

Results

The mean follow-up period lasted 57 months. To the last follow-up, there were no cases of internal fixation loosening, failure and other complications. Titanium mesh or interbody bone grafts were in good position. Spinal kyphosis was not observed. Interbody fusion was achieved for all cases. The average fusion time was 4.5 months. Based on visual analogue scale (VAS) pain scores, percentage of vertebral body height loss and Cobb angle, the difference was statistically significant between the preoperative period and postoperative one year or final follow-up (P < 0.05). Results at postoperative one year and final follow-up were better than the preoperative period. However, the difference was not significant between postoperative one year and final follow-up (P > 0.05).

Conclusions

Good midterm results on clinical and radiologic evaluation of anterior decompression with single segmental spinal Interbody fusion for suitable patients with Denis type B thoracolumbar burst fracture can be achieved. The incident rate of relative complications is low.     

Staged external and internal locked plating for open distal tibial fractures: A retrospective study of 16 patients

Background and purpose

Based on reported success with staged treatment of distal tibial fractures, we designed a 2-stage protocol including external/internal locked plating. We retrospectively assessed the outcome of open distal tibial fractures treated according to this protocol.

Patients and methods

From March 2006 through July 2008, 16 patients who sustained open distal tibial fractures were treated by a two-stage protocol. The first stage consisted of low-profile, locked plates for temporary external fixation after debridement and anatomic reduction, followed by soft tissue reconstruction. The second stage consisted of locked plates for definitive internal fixation, using minimally invasive percutaneous osteosynthesis. All fractures were followed for median 2 (1–3) years.

Results

The reduction was classified as being good in 15 patients and fair in 1 patient. All fractures united at a median of 6 (6–12) months. At the latest follow-up, 7 patients had excellent and 9 had good Iowa ankle scores; ankle motion ranged from a median of 10 (5–20) degrees of dorsiflexion to 40 (20–60) degrees of plantar flexion.

Interpretation

We believe that the 2-stage external/internal locked plating technique is an effective procedure for treatment of open distal tibial fractures in patients who need a long period of external fixation. We achieved good reduction with immediate ankle-sparing stable fixation. Soft tissue reconstruction and subsequent definitive fixation led to union of all fractures with good function.     

Reconstruction of iliac crest with bovine cancellous allograft after bone graft harvest for symphysis pubis arthrodesis

Purpose

The aim of this study was to evaluate the safety and efficiency, as well as the incorporation characteristics of a specific type of xenograft used for iliac crest defects post-harvesting tri-cortical iliac crest bone graft.

Methods

Sixteen patients diagnosed with chronic anterior pelvic pain were operated for pubic symphysis fusion. The tri-cortical graft harvested from the iliac crest was inserted into the pubic symphysis and compressed with a reconstruction plate. The defect in the iliac crest was filled with a block of cancellous bovine substitute (Tutobone®). The length of iliac crest defect, time to fusion of pubic symphysis, time to incorporation of the graft and complications were recorded. The postoperative pain and patients’ satisfaction were evaluated.

Results

The median age of patients was 36.5 years (range 27–75). Fusion was obtained in 15 patients (94 %). The median time to fusion was four months (range three to seven). The length of the iliac crest bone defect ranged from 40 to 70 mm. Integration of the bovine substitute was achieved in 15 patients (94 %) over a median period of three months (range two to six). The postoperative median pain score was 2 (range 1–5). Twelve patients (75 %) reported good satisfaction. No major complications or allergic reactions were observed.

Conclusions

The xenograft used in this study provided a safe and effective method of reconstruction of iliac crest donor site defects. It has satisfactory incorporation, high biocompatibility and no signs of inflammatory reactions. This new technique is simple and easily reproducible in routine clinical practice.     

Is Cervical Disc Arthroplasty Superior to Fusion for Treatment of Symptomatic Cervical Disc Disease? A Meta-Analysis

Background

As the current standard treatment for symptomatic cervical disc disease, anterior cervical decompression and fusion may result in progressive degeneration or disease of the adjacent segments. Cervical disc arthroplasty was theoretically designed to be an ideal substitute for fusion by preserving motion at the operative level and delaying adjacent level degeneration. However, it remains unclear whether arthroplasty achieves that aim.

Questions/purposes

We investigated whether cervical disc arthroplasty was associated with (1) better function (neck disability index, pain assessment, SF-36 mental and physical health surveys, neurologic status) than fusion, (2) a lower incidence of reoperation and major complications, and (3) a lower risk of subsequent adjacent segment degeneration.

Methods

We conducted a comprehensive search in MEDLINE^®, EMBASE, and Cochrane Central Register of Controlled Trials and identified 503 papers. Of these, we identified 13 reports from 10 randomized controlled trials involving 2227 patients. We performed a meta-analysis of functional scores, rates of reoperation, and major complications. The strength of evidence was evaluated by using GRADE profiler software. Of the 10 trials, six trials including five prospective multicenter FDA-regulated studies were sponsored by industry. The mean followups of the 10 trials ranged from 1 to 5 years.

Results

Compared with anterior cervical decompression and fusion, cervical disc arthroplasty had better mean neck disability indexes (95% CI, −0.25 to −0.02), neurologic status (risk ratio [RR], 1.04; 95% CI, 1.00–1.08), with a reduced incidence of reoperation related to the index surgery (RR, 0.42; 95% CI, 0.22–0.79), and major surgical complications (RR, 0.45; 95% CI, 0.27–0.75) at a mean of 1 to 3 years. However, the operation rate at adjacent levels after two procedures was similar (95% CI, 0.31–1.27). The three studies with longer mean followups of 4 to 5 years also showed similar superiority of all four parameters of cervical disc arthroplasty compared with fusion.

Conclusions

For treating symptomatic cervical disc disease, cervical disc arthroplasty appears to provide better function, a lower incidence of reoperation related to index surgery at 1 to 5 years, and lower major complication rates compared with fusion. However, cervical disc arthroplasty did not reduce the reoperation rate attributable to adjacent segment degeneration than fusion. Further, it is unclear whether these differences in subsequent surgery including arthroplasty revisions will persist beyond 5 years.     

A radiographic and clinical comparison of reamer–irrigator–aspirator versus iliac crest bone graft in ankle arthrodesis

Purpose

We evaluated radiographic fusion at follow-up and complication rates in patients who had either iliac crest (ICBG) or femoral reamer–irrigator–aspirator (RIA) bone graft for tibiotalar fusion.

Methods

We retrospectively reviewed charts and radiographs of all patients who had a tibiotalar fusion from August 2007 to February 2011. Records were analysed for patient demographics, complications, and clinical symptoms. Radiographs were reviewed in sequential order by two fellowship-trained foot and ankle surgeons and one orthopaedic surgeon who specialises in foot and ankle surgery to determine radiographic fusion at routine follow-up. Patients were contacted to determine current visual analog scores (VAS) at their graft site.

Results

Mean patient age was 49.4 ± 12.1 years in the RIA group and 49.3 ± 15.4 years in the ICBG group (p = .97). Pre-operative characteristics showed no significant differences between groups. The ICBG group had significantly more nonunions than the RIA group (six vs. one, p = 0.04). Two patients in the ICBG had chronic pain at their graft site based on their VAS score; there were none in the RIA group. Radiographic fusion at follow-up was similar between groups, with no significant difference (12.48 ± 3.85 weeks vs.12.21 ± 3.19 weeks, p = .80).

Conclusions

There was a significantly higher nonunion rate in the ICBG group, but both groups had a solid radiographic bony fusion at similar follow-up time points. Our results suggest RIA bone graft is a viable alternative to ICBG for tibiotalar fusion.     

Lumbopelvic fusion with a new fixation technique in lumbosacral agenesis: three cases

Purpose

Patients with lumbosacral agenesis characteristically sit on their iliac wings with their torsos bent forward, which yields an increase in intra-abdominal pressure and, subsequently, negative effects on their diaphragm. The sacrum is not available as an anchor point for instrumentation. Dunn-McCarthy rods or Galveston fixations cannot be performed due to these limited anatomic properties. On the other hand, the absence of necessary bone mass for fusion anteriorly limits the fusion interventions to the posterior. Therefore, a secure and rigid fixation is essential to preclude the need for an external support. There are limited publications discussing different techniques due to the relatively rare incidence of the disease. We report the clinical and radiological results of a new technique applied to three patients in which previously recommended methods are modified.

Methods

Two 6-year-old female patients and one 5-year-old male patient with lumbosacral agenesis underwent posterior lumbopelvic instrumentation and fusion. Together with standard pedicle screw spinal instrumentation, pelvic fixation is obtained with a combination of supero-inferior directed rod and/or screw to overcome deforming forces created at the flexion–extension pivot points of the lumbopelvic junction. Autogenic anterior tibial cortical structural graft is used for laminopelvic bridging, and demineralized bone matrix is used for the augmentation of osteoinduction. A single leg hip spica is applied for 4 months to protect the fixation.

Results

Total correction yielded an aligned spine with a posture that allows for sitting on the ischial spines for all three patients. Solid fusion was observed to maintain this correction at the final follow-up.

Conclusion

The use of new-generation pediatric spinal instrumentation systems with a new technique without knee disarticulation provides a safe and effective fixation and fusion in lumbosacral agenesis.