Reoperation after lumbar disc surgery in two hundred and seven patients

Purpose

The purpose of this study was to compare the causes and characteristics of reoperations after different primary operations for lumbar disc herniation (LDH).

Methods

Out of a series of 5,280 patients who underwent operations for LDH between 2001 and 2012, 207 patients (135 male and 72 female, mean age 47.7 years) underwent primary and revision operations, which were included in this study. The following clinical parameters were retrospectively assessed: the primary surgical methods, the intervals between primary and revision operations, and surgical findings in the revisions.

Results

In total, 232 lumbar discs underwent reoperations. One hundred and nineteen reoperations were performed after microendoscopic discectomy (MED group), 68 after percutaneous endoscopic lumbar discectomy (PELD group) and 45 after open disc surgery (open group). The locations of revision operations had priority over those of primary surgery, with a moderate correlation (kappa coefficient = 0.533). A total of 46.6 % of reoperations were performed within 0.5 years after primary surgery, and 35.3 % were performed between one and five years. Real recurrent herniation (homolateral herniations at the same level) was significantly more common than other reoperative surgical findings (70.6 % in PELD group, 47.1 % in MED group, 37.8 % in open group). The overall mean interval until revision surgery was 18.9 months (8.1 months in the PELD group vs. 19.7 months in the MED group vs. 33.1 months in the open group, p < 0.01).

Conclusions

For LDH, real recurrent herniation was the most common cause of reoperations, and more reoperations for real recurrent herniations and shorter intervals were found after minimally invasive endoscopic discectomy than after open disc surgery.     

A systematic review and meta-analysis of biological treatments targeting tumour necrosis factor α for sciatica

Purpose

Systematic review comparing biological agents, targeting tumour necrosis factor α, for sciatica with placebo and alternative interventions.

Methods

We searched 21 electronic databases and bibliographies of included studies. We included randomised controlled trials (RCTs), non-RCTs and controlled observational studies of adults who had sciatica treated by biological agents compared with placebo or alternative interventions.

Results

We pooled the results of six studies (five RCTs and one non-RCT) in meta-analyses. Compared with placebo biological agents had: better global effects in the short-term odds ratio (OR) 2.0 (95 % CI 0.7–6.0), medium-term OR 2.7 (95 % CI 1.0–7.1) and long-term OR 2.3 [95 % CI 0.5 to 9.7); improved leg pain intensity in the short-term weighted mean difference (WMD) −13.6 (95 % CI −26.8 to −0.4), medium-term WMD −7.0 (95 % CI −15.4 to 1.5), but not long-term WMD 0.2 (95 % CI −20.3 to 20.8); improved Oswestry Disability Index (ODI) in the short-term WMD −5.2 (95 % CI −14.1 to 3.7), medium-term WMD −8.2 (95 % CI −14.4 to −2.0), and long-term WMD −5.0 (95 % CI −11.8 to 1.8). There was heterogeneity in the leg pain intensity and ODI results and improvements were no longer statistically significant when studies were restricted to RCTs. There was a reduction in the need for discectomy, which was not statistically significant, and no difference in the number of adverse effects.

Conclusions

There was insufficient evidence to recommend these agents when treating sciatica, but sufficient evidence to suggest that larger RCTs are needed.

Electronic supplementary material

The online version of this article (doi:10.1007/s00586-013-2739-z) contains supplementary material, which is available to authorized users.     

The safety and efficacy of minimally invasive discectomy: a meta-analysis of prospective randomised controlled trials

Purpose

The objective of this study was to compare the safety and efficacy of minimally invasive discectomy (MID) with standard discectomy (SD) and determine whether the use of the MID technique could decrease the recurrence of lumbar disc herniation (LDH) after the surgery.

Methods

In February 2014, a comprehensive search was performed in PubMed, EMBASE, Web of Science, Cochrane Library and the Chinese Biological Medicine Database. Only randomised controlled trials (RCT) that compared MID with SD for the surgical management of LDH were included. These trials were carefully picked out following the inclusion and exclusion criteria. Using the Cochrane Collaboration guidelines, two authors independently extracted data and assessed these trials’ quality. The age of the patients, size of incision, surgical time, blood loss, visual analogue scale (VAS) score after the surgery, hospital stay, disc herniation recurrence, X-ray exposure and surgical costs in these studies were abstracted and synthesised by a meta-analysis with RevMan 5.2.0 software, and the main results (VAS score after the surgery and disc herniation recurrence) of publication bias were examined by Stata 12.0.

Results

Overall, 16 trials involving 2,139 patients meeting our criteria were included and analysed. Comparing MID and SD, the former was more likely to increase disc herniation recurrence [relative risk (RR) = 1.95, 95 % confidence interval (CI) 1.19–3.19, p = 0.008], and it involved a smaller size of incision [mean difference (MD) = −1.91, 95 % CI −3.33 to −0.50, p = 0.008], shorter hospital stay, longer operating time (MD = 11.03, 95 %C I 6.62–15.44, p < 0.00001) and less blood loss (MD = −13.56, 95 % CI −22.26 to −4.87, p = 0.002), while no statistical difference appeared with regard to the age of the patients, VAS score after the surgery, X-ray exposure, hospital stay and surgical costs.

Conclusions

Based on available evidence, MID results in less suffering for patients during the hospital course with a similar clinical efficacy compared to SD. This makes MID a promising procedure for patients with LDH; however, to popularise it greater effort is required to reduce disc herniation recurrence.     

Incidence of Low Back Pain After Lumbar Discectomy for Herniated Disc and Its Effect on Patient-reported Outcomes

Background

Long-term postdiscectomy degenerative disc disease and low back pain is a well-recognized disorder; however, its patient-centered characterization and quantification are lacking.

Questions/purposes

We performed a systematic literature review and prospective longitudinal study to determine the frequency of recurrent back pain after discectomy and quantify its effect on patient-reported outcomes (PROs).

Methods

A MEDLINE search was performed to identify studies reporting on the frequency of recurrent back pain, same-level recurrent disc herniation, and reoperation after primary lumbar discectomy. After excluding studies that did not report the percentage of patients with persistent back or leg pain more than 6 months after discectomy or did not report the rate of same level recurrent herniation, 90 studies, which in aggregate had evaluated 21,180 patients, were included in the systematic review portion of this study. For the longitudinal study, all patients undergoing primary lumbar discectomy between October 2010 and March 2013 were enrolled into our prospective spine registry. One hundred fifteen patients were more than 12 months out from surgery, 103 (90%) of whom were available for 1-year outcomes assessment. PROs were prospectively assessed at baseline, 3 months, 1 year, and 2 years. The threshold of deterioration used to classify recurrent back pain was the minimum clinically important difference in back pain (Numeric Rating Scale Back Pain [NRS-BP]) or Disability (Oswestry Disability Index [ODI]), which were 2.5 of 10 points and 20 of 100 points, respectively.

Results Systematic Review

The proportion of patients reporting short-term (6–24 months) and long-term (> 24 months) recurrent back pain ranged from 3% to 34% and 5% to 36%, respectively. The 2-year incidence of recurrent disc herniation ranged from 0% to 23% and the frequency of reoperation ranged from 0% to 13%.

Prospective Study

At 1-year and 2-year followup, 22% and 26% patients reported worsening of low back pain (NRS: 5.3 ± 2.5 versus 2.7 ± 2.8, p < 0.001) or disability (ODI%: 32 ± 18 versus 21 ± 18, p < 0.001) compared with 3 months.

Conclusions

In a systematic literature review and prospective outcomes study, the frequency of same-level disc herniation requiring reoperation was 6%. Two-year recurrent low back pain may occur in 15% to 25% of patients depending on the level of recurrent pain considered clinically important, and this leads to worse PROs at 1 and 2 years postoperatively.     

Experimental Disc Herniation in the Rat Causes Downregulation of Serotonin Receptor 2c in a TNF-dependent Manner

Background

During recent decades, the knowledge of the pathophysiology of disc herniation and sciatica has drastically improved. What previously was considered a strict biomechanical process is now considered a more complex interaction between leaked nucleus pulposus and the tissue in the spinal canal. An inflammatory reaction, with tumor necrosis factor (TNF) playing an essential role, has been demonstrated. However, the exact mechanisms of the pathophysiology of disc herniation remain unknown.

Questions/purposes

In this study we use an animal model to investigate (1) if and/or how experimental disc herniation affects gene expression in the early phase (24 hours postsurgery) in the dorsal root ganglion; and (2) if TNF inhibition can reduce any observed changes.

Methods

A rat model of disc herniation was used. Twenty rats were evenly divided into four groups: naïve, sham, disc herniation, and disc herniation with TNF inhibition. The dorsal root ganglion of the affected nerve root was harvested 24 hours after surgery and analyzed with a TaqMan Low Density Array^® quantitative polymerase chain reaction assay. Gene expression levels in sham were compared with disc herniation to assess question 1 and disc herniation to disc herniation with TNF inhibition to assess question 2.

Results

Experimental disc herniation caused a decrease in the expression of the serotonin receptor 2c gene (p = 0.022). TNF inhibition was found to reduce the observed decrease in expression of serotonin receptor 2c (p = 0.037).

Conclusions

Our results suggest that a decrease in the expression of the serotonin receptor 2c gene may contribute to the pathophysiology of disc herniation. Further research on its involvement is warranted.

Clinical Relevance

This pilot study gives a brief insight into cellular changes that may contribute to the pathophysiology of disc herniation. This knowledge may contribute to the development of more and better treatment options for patients with disc herniation and sciatica.     

A decade’s experience in lumbar spine surgery in Belgium: sickness fund beneficiaries, 2000–2009

Purpose

The purpose is to study rates, trends, geographic variations and outcome of lumbar spine surgery in the Belgian population during the last decade.

Methods

This is a retrospective cohort study using administrative data of the largest Belgian sickness fund from January 1, 2000 through December 31, 2009. Cases included lumbar laminectomy, combined discectomy and fusion, posterior interarticular fusion, anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF) and standard discectomy. The main outcome measures were age- and sex-adjusted rates of lumbar spine surgery, 1-year mortality, 1-year iterative surgery, no return to work (RTW) rate 1 year after surgery and length of hospital stay. Multivariate logistic regression analysis was used to determine the association between age, sex, geographic region, type of surgery, year of intervention and duration of pre-operative sick leave on outcome.

Results

Spine surgery rates rose 44 % from 2001 through 2009 and data for 2009 showed twofold variations in spine surgery rates among 10 Belgian provinces. Reported 1-year mortality varied from 0.6 to 2.5 % among surgical procedures performed in 2008. The overall 5-year reoperation rate was 12 %. RTW rates 1 year after standard discectomy, ALIF, PLIF and combined discectomy and fusion for the follow-up sample of 2008 were 14.4, 22.7, 26.1 and 30.6 %, respectively. The median length of hospital stay significantly decreased throughout the decade. Type of surgery and geographic region were significantly related to patient outcomes.

Conclusions

Regional variations highlight professional uncertainty and controversy. The study results point to the need for peer comparisons and surgeon feedback.     

Medial patella retinaculum plasty for treatment of habitual patellar dislocation in adolescents

Purpose

The surgical technique, medial patellar retinaculum plasty, can almost restore both static and dynamic stability and verge on anatomical repair for the treatment of habitual patellar dislocation in adolescents.

Methods

In accordance with the injury patterns of the medial patellar retinaculum through knee MRI, we repaired different injury sites with this surgical procedure. We reviewed this technique in 16 patients with an average age of 15 years. Retrospective review of charts and radiographs immediately after the surgery up to the latest follow-up (range 12–36 months) was undertaken.

Results

All patients were evaluated clinically and radiologically over an average of 20.7 months. The recovery of knee mobility results were good. No recurrence of patellar instability has been found.

Conclusion

We think this could be a valid technique to treat habitual patellar dislocation in adolescents.     

Three- and four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct

Introduction

Three- or four-level anterior cervical discectomy and fusion with autograft and plate fixation have demonstrated relatively good fusion rates and outcomes, but donor site morbidity and the limitations of autograft harvest remain problematic. The purpose of this study is to assess the radiographic and clinical outcomes of three- or four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct.

Methods

This retrospective review included 43 consecutive patients who underwent three- or four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct (three level: 39 cases, four level: 4 cases). The fusion rate, time to fusion, Cobb angle and disc height were assessed radiographically. Clinical outcomes were evaluated with the VAS, NDI, and SF36 scores. Complications were also recorded.

Results

Solid fusion was achieved in all the patients, and mean time to fusion was 13.7 ± 5.1 weeks. The postoperative Cobb angle, lordotic angle, and disc height (5.6°, 10.5° and 3.15 mm, respectively) increased significantly compared to preoperative values (p = 0.038, p = 0.032, and p = 0.0004, respectively), and these improvements were maintained through final follow-up. The postoperative NDI (17.2), VAS (2.8), and SF36 (13.1) scores increased significantly compared to the preoperative scores (p = 0.026, p = 0.0007 and p = 0.041, respectively). Complications included three cases of respiratory difficulty, four cases of dysphagia and one case of hoarseness. There were no cases of donor site morbidity.

Conclusions

Three- or four-level anterior cervical discectomy and fusion with a PEEK cage, and plate construct provide good clinical and radiographic outcomes including high fusion rates, low complication rates, low donor site morbidity, and good maintenance of the lordotic angle and disc height in the treatment of multilevel cervical spondylosis.     

Outcomes of Lumbar Discectomy in Elite Athletes: The Need for High-level Evidence

Background

Although lumbar discectomy for treatment of lumbar disc herniation in the general population generally improves patients’ pain, function, and validated outcomes scores, results of treatment in elite athletes may differ because of the unique performance demands required of competitive athletes.

Questions/purposes

We performed a systematic review to answer the following questions: (1) What proportion of athletes return to play after lumbar discectomy, and what is the effect of sport? (2) What is the expected recovery time after lumbar discectomy in elite athletes? (3) What is the expected career length and performance of elite athletes after lumbar discectomy?

Methods

We performed a systematic literature review of articles of lumbar discectomy in the elite athlete population through the MEDLINE and EMBASE databases from 1947 to 2013. Elite athletes were defined as professional, Olympic, or National Collegiate Athletic Association Division I collegiate level. A hand search of the references of all key articles was performed to ensure inclusion of all relevant studies. Information regarding study design, types of athletes, level of sport, recovery time, return to sport, length of career after surgery, and career performance after surgery was extracted. Ten articles met the inclusion and exclusion criteria for this review. These articles consisted of levels III and IV data and were graded based on the Methodological Index for Non-Randomized Studies (MINORS) scale.

Results

Overall, the studies included in this review found that 75% to 100% of athletes were able to return to elite competition after operative treatment. In general, a higher proportion of baseball players returned to elite competition compared with other athletes. The reported recovery period after lumbar discectomy ranged from 2.8 to 8.7 months. The average career length after lumbar discectomy ranged from 2.6 to 4.8 years. Elite athletes reached an average of 64.4% to 103.6% of baseline preoperative statistics after lumbar discectomy with variable performance based on sport.

Conclusions

A high proportion of elite athletes undergoing lumbar discectomy return to play with variable performance scores on return. Future prospective studies are needed to compare the recovery time, career longevity, and performance for athletes undergoing lumbar discectomy versus nonoperative treatment for lumbar disc herniation.     

Morphological changes in disc herniation in the lower cervical spine: an ultrastructural study

Introduction

The basis of disc degeneration is still unknown, but is believed to be a cell-mediated process. Apoptosis might play a major role in degenerative disc disease (DDD). The aim of this study was to correlate the viability of disc cells with the radiological degeneration grades (rDG) in disc herniation.

Materials and methods

Forty anterior IVD’s (C4–C7) from 39 patients with DDD were studied histologically and ultrastructurally to quantify healthy, “balloon”, chondroptotic, apoptotic and necrotic cells. Patients were classified to their rDG, as having either prolapse (P: DGII + III) and/or osteochondrosis (O: DGIV + V). Similar studies were undertaken on eight control discs.

Results

Cell death by necrosis (mean 35%) was common but differed not significantly in both groups. All patients with a disc prolapse DGII + III revealed balloon cells (iAF: mean 32%). All appeared alive and sometimes were hypertrophic. However, significantly less balloon cells were found in the O-Group. Control samples revealed no evidence of “balloon” cells in DGII and only a minor rate in DGIII.

Conclusion

According to the different rDG, quantitative changes were obvious in healthy and “balloon” cells, but not for cell death. At the moment it can only be hypothesized if “balloon” cells are part of a repair strategy and/or cause of disc herniation.     

Is Unilateral Kyphoplasty as Effective and Safe as Bilateral Kyphoplasties for Osteoporotic Vertebral Compression Fractures? A Meta-analysis

Background

An osteoporotic vertebral compression fracture is a common condition in elderly people, especially women. The percutaneous kyphoplasty is an effective treatment for osteoporotic vertebral compression fractures. Controversy remains regarding whether a unilateral or a bilateral approach is superior, and to our knowledge, there have been no large studies comparing these two approaches, therefore a meta-analysis synthesizing the data on this question is warranted.

Questions/purposes

We asked the following questions: (1) Is there evidence to suggest a benefit in clinical outcome as assessed by the VAS and Oswestry Disability Index of a unilateral kyphoplasty or bilateral kyphoplasties? (2) Are the complications associated with the two approaches different? (3) Do the procedures result in different kyphosis angle reduction or anterior vertebral height restoration? (4) Is the surgical time for the procedures different?

Methods

We searched the Cochrane Library, PubMed MEDLINE, EMBASE, Web of Knowledge MEDLINE (January 1980 to June 2013), and reference lists of eligible prospective studies. The levels of the evidence and recommendations were assessed using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Five studies encompassing 253 patients met the inclusion criteria.

Results

The short- and long-term clinical outcomes as assessed by the VAS and Oswestry Disability Index showed no differences between unilateral and bilateral kyphoplasties (p = 0.41, p = 0.60 for VAS; p = 0.10, p = 0.36 for Oswestry Disability Index). There were no differences in complications such as cement leakage and adjacent vertebral fractures associated with the two approaches (p = 0.43 and p = 0.95). The kyphosis angle reduction and anterior vertebral height restoration showed no difference between the two approaches (p = 0.34 and p = 0.46). The unilateral approach was shorter in terms of surgical time (mean difference, −24.98; p < 0.0001). The overall GRADE system evidence quality was very low, with only high evidence for operation time, which lessens our confidence in recommendations.

Conclusions

Unilateral and bilateral percutaneous kyphoplasties appear to be safe and effective for treating osteoporotic vertebral compression fractures. No clinically important differences were found between them. Considering less operation time and less cost, we suggest that a unilateral percutaneous kyphoplasty is advantageous, but because of the poor quality of the evidence, high-quality randomized controlled trials are required to resolve this issue.     

Does Surgical Timing Influence Functional Recovery After Lumbar Discectomy? A Systematic Review

Background

The impact of the duration of preoperative symptoms on outcomes after lumbar discectomy has not been sufficiently answered in a single study but is a potentially important clinical variable.

Questions/purposes

A systematic review was performed to answer two questions: (1) Does symptomatic duration before surgery influence functional recovery after lumbar discectomy? (2) What is the time point for intervention beyond which the extent of postoperative recovery might be compromised?

Methods

The systematic review began with a query of PubMed using a structured algorithm comprised of medical subject heading terms. This was supplemented by a keyword search in PubMed along with queries of Embase, Scopus, and Web of Science and searches of reference lists as well as the tables of contents of relevant journals. Eligible studies were those that evaluated aspects of recovery after elective discectomy and stratified duration of symptoms before surgery. Included papers were abstracted by two authors and determinations regarding the period of symptom duration and its impact on outcome were recorded. Eleven studies met all inclusion criteria. No prospectively randomized trials addressed our study questions.

Results

Nine of 11 studies, four of which were prospective, maintained that longer symptom duration adversely impacted postsurgical recovery. There were substantial differences among the critical periods of symptom duration reported by individual studies, which ranged from 2 to 12 months. A preponderance of studies (five of nine) reported that surgical interventions could be performed at periods of 6 months or greater without impacting recovery.

Conclusions

Longer symptom duration had an adverse impact on results in most studies after lumbar discectomy. A possible point beyond which outcomes may be compromised is 6 months after symptom onset. Limitations in the literature surveyed, however, prevent firm conclusions.     

Prevalence of complications in neuromuscular scoliosis surgery: a literature meta-analysis from the past 15 years

Purpose

Our objectives were primarily to review the published literature on complications in neuromuscular scoliosis (NMS) surgery and secondarily, by means of a meta-analysis, to determine the overall pooled rates (PR) of various complications associated with NMS surgery.

Methods

PubMed and Embase databases were searched for studies reporting the outcomes and complications of NMS surgery, published from 1997 to May 2011. We focused on NMS as defined by the Scoliosis Research Society’s classification. We measured the pooled estimate of the overall complication rates (PR) using a random effects meta-analytic model. This model considers both intra- and inter-study variation in calculating PR.

Results

Systematic review and meta-analysis were performed for 68 cohort and case–control studies with a total of 15,218 NMS patients. Pulmonary complications were the most reported (PR = 22.71 %) followed by implant complications (PR = 12.51 %), infections (PR = 10.91 %), neurological complications (PR = 3.01 %) and pseudoarthrosis (PR = 1.88 %). Revision, removal and extension of implant had highest PR (7.87 %) followed by malplacement of the pedicle screws (4.81 %). Rates of individual studies have moderate to high variability. The studies were heterogeneous in methodology and outcome types, which are plausible explanations for the variability; sensitivity analysis with respect to age at surgery, sample size, publication year and diagnosis could also partly explain this variability. In regard to surgical complications affiliated with various surgical techniques in NMS, the level of evidence of published literature ranges between 2+ to 2−; the subsequent recommendations are level C.

Conclusion

NMS patients have diverse and high complication rates after scoliosis surgery. High PRs of complications warrant more attention from the surgical community. Although the PR of all complications are affected by heterogeneity, they nevertheless provide valuable insights into the impact of methodological settings (sample size), patient characteristics (age at surgery), and continual advances in patient care on complication rates.

Electronic supplementary material

The online version of this article (doi:10.1007/s00586-012-2542-2) contains supplementary material, which is available to authorized users.     

Four-level anterior cervical discectomies and cage-augmented fusion with and without fixation

Purpose

Anterior cervical decompression and fusion is a well-established procedure for the treatment of cervical spinal canal stenosis. In this study, we evaluated the necessity of spinal instrumentation after four-level anterior cervical decompression and cage fusion.

Methods

From January 2006 until August 2008, 25 patients (8 females and 17 males) (mean age 63.9 ± 7.9 years) suffering from spinal stenosis C3–C7 underwent anterior decompression and interbody fusion. The patients were divided into two groups. Four-level discectomy and cage fusion was performed in all patients. In group A including nine patients, posterior instrumentation with a lateral mass screw-rod system was added, while in group B including 16 patients, additional instrumentation was not performed. The mean duration of follow-up was 48.6 months (average 25–67 months).

Results

Clinically, the mean value for the Neck Disability Index improved from 40 ± 23.25 at presentation to 16.31 ± 15.09 at the final follow-up. The difference between the two groups was statistically not significant. Radiologically, the criteria for solid bony fusion were achieved successfully in all patients of group A, and in 87.5 % of patients in group B. The difference between the two groups was statistically not significant. The fused segment was then evaluated in the sagittal radiographs as regards the height and the lordosis angle. The loss in the height as well as the loss in the lordosis angle was more when posterior instrumentation was not added. However, the difference between the two groups was not statistically significant.

Conclusion

Stand-alone intersomatic cage fusion is an acceptable line of treatment for four-level cervical disc disease, both clinically and radiologically. Although the addition of posterior instrumentation yields better radiological results, the difference does not reach the statistical significance level.     

Efficacy of multilevel anterior cervical discectomy and fusion versus corpectomy and fusion for multilevel cervical spondylotic myelopathy: a minimum 5-year follow-up study

Purpose

We evaluated radiologic and clinical outcomes to compare the efficacy of anterior cervical discectomy and fusion (ACDF) and anterior corpectomy and fusion (ACCF) for multilevel cervical spondylotic myelopathy (CSM).

Methods

A total of 40 patients who underwent ACDF or ACCF for multilevel CSM were divided into two groups. Group A (n = 25) underwent ACDF and group B (n = 15) ACCF. Clinical outcomes (JOA and VAS scores), perioperative parameters (length of hospital stay, blood loss, operation time), radiological parameters (fusion rate, segmental height, cervical lordosis), and complications were compared.

Results

Both group A and group B demonstrated significant increases in JOA scores and significant decreases in VAS. Patients who underwent ACDF experienced significantly shorter hospital stays (p = 0.031), less blood loss (p = 0.001), and shorter operation times (p = 0.024). Both groups showed significant increases in postoperative cervical lordosis and achieved satisfactory fusion rates (88.0 and 93.3 %, respectively). There were no significant differences in the incidence of complications among the groups.

Conclusions

Both ACDF and ACCF provide satisfactory clinical outcomes and fusion rates for multilevel CSM. However, multilevel ACDF is associated with better radiologic parameters, shorter hospital stays, less blood loss, and shorter operative times.     

Contemporary femoral designs in total knee arthroplasty: effects on the patello-femoral congruence

Purpose

The objective of this study was to evaluate the radiological and clinical correlations between implant design and patellar positioning in patients who underwent TKA utilizing femoral implants with modern designs.

Methods

Thirty consecutive PFC PS Sigma TKAs, characterized by a new prolonged anterior flange and a “smoother” trochlea, were prospectively reviewed. All patellae were replaced. All patients were evaluated pre-operatively and prospectively at two years follow-up both clinically according to the Knee Society score as well as radiographically. This included computed tomography (CT); patellar tilt, patellar conformity angle, patellar lateralization, and femoral component external-rotation in relation to the clinical trans-epicondylar axis.

Results

Average patellar tilt at follow-up was 3° (±7.5°) with respect to a pre-operative 18.5° (±8.5°). Average patellar congruence angle at follow-up was −3° (range, −11° to +9°) with respect to a pre-operative 10.3° (range, + 1.5° to 25.5°). Average lateralization index at follow-up was 2.7 mm (range, −3.4 mm to +7.1 mm) with respect to a pre-operative 12.2 mm (± 4.8 mm). Femoral component positioning related to the trans-epicondylar axis showed an external rotation of 2.80° (± 2.10°) at follow-up with respect to 5.7° (± 1.80°). Clinically, two (6.6%) patients reported patello-femoral complications related to imperfections in the surgical technique more than the implant''s design.

Conclusions

This study highlighted that modern femoral designs in TKA allow for a correct reproducibility of a normal patello-femoral conformity. Strict surgical principles are paramount to avoid patello-femoral complications even when modern implants are used.