Frequency and predictors of implant-related complications after posterior cervical fusion.

STUDY DESIGN: Retrospective, observational study. PURPOSE: To determine the frequency and predictors of implant-related complications in adults after posterior cervical fusion. OVERVIEW OF LITERATURE: Published literature on lumbosacral fusion suggest that implant-related complications are not uncommon. Although posterior cervical fusion is a common operation, data on frequency and predictors of implant-related complications after posterior cervical fusion is still scarce. METHODS: 86 patients (with 740 screws) who underwent posterior cervical fusion were included. Implant-related complications were identified by the presence of: (1) halo sign, (2) screw pull-out/breakage (3) post-operative kyphosis and (4) implant-related complications requiring revision surgery. These were stratified into two groups: (a) minor - isolated halo sign or screw pull-out/breakage (b) major - post-operative kyphosis > 10 degrees, and revision surgery. Demographic, operative and radiological data was collected. Rates of implant-related complications were determined and associated risk factors identified. RESULTS: 33 (38.4%) patients had signs of implant-related complications. Of these, 29 (87.9%) had minor complications and 4 (12.1%) had major complications. Charlson Comorbidity Index (CCI) (p = 0.03179) and pre-op C2-C7 sagittal vertical alignment (SVA) (p = 0.02449) were the only significant risk factors for all-cause implant-related complications during multivariate logistic regression. Other intraoperative parameters (type of screw, length of fusion, levels decompressed, and extension of fusion beyond the levels decompressed) were not significantly associated with implant-related complications. CONCLUSIONS: Implant-related complications are not uncommon but rarely require revision surgery. Higher pre-operative SVA and CCI were significant risk factors; length of construct and extent of decompression were not. These findings may assist clinicians when deciding the extent of fusion and in selecting patients for closer follow-up.

We assessed the frequency and predictors of implant-related complications in adults after posterior cervical fusion. Implant-related complications (halo sign, screw pull-out/breakage, post-operative kyphosis) are not uncommon but rarely require revision surgery. Higher pre-operative SVA and CCI were significant risk factors; length of construct and extent of decompression were not.

Correction of degenerative lumbar coronal deformity using asymmetrical interbody cages: Surgical technique and case report.

In adult degenerative spondylosis, much emphasis has been placed upon recognizing the sagittal plane deformity and techniques to restore this alignment. However, the coronal plane deformity has not received much attention and, if left uncorrected, may lead to poorer outcomes. Here, we present a case of degenerative lumbar scoliosis with a rigid coronal malalignment secondary to a dysplastic sacrum. We performed staged T11-pelvis lateral and posterior approach to address this deformity. For the first stage, a lateral lumbar interbody fusion was performed at the concavity of the curve from L3 to L5. For the second stage, through posterior approach, a long-segment instrumentation from T11 to pelvis was done along with bilateral asymmetrical posterior lumbar interbody fusion of L5-S1 to level the L5 vertebra at the hemi-curve, thereby leveling the coronal deformity. We propose, for cases with a rigid coronal deformity due to bony dysplasia, correction through the disc space using asymmetrical interbody cages as in this case offers the surgeon an option to achieve a desired correction, without the need for vertebral osteotomy.

Numbness after medial unicompartmental knee arthroplasty: Prevalence and effect on functional outcome.

BACKGROUND: The prevalence of skin sensation alteration after total knee arthroplasty is well established but less so in medial unicompartmental knee arthroplasty (MUKA). The aim of this study was to determine the prevalence, extent of numbness and its effect on mid-term functional outcomes after MUKA. METHODS: A level 2 prospective cohort study was conducted. Twenty patients (21 knees) were recruited. Demographics, length of surgical incision and the thigh-to-calf ratio was recorded. At the 1-year postoperative period, the extent of numbness was measured using a quantifiable grid-based system for both pinprick and fine touch. Preoperative, 3 months and 1 year postoperative Knee Society Scores (KSS) and 36-Item Short Form Health Survey (SF-36) scores were recorded. RESULTS: At the 1-year postoperative period, the prevalence of numbness to both fine touch and pin prick was 58% and 66%, respectively. The mean area of numbness to fine touch and pin prick was 336 mm2 and 521 mm2, respectively. The prevalence and extent of numbness was not significantly associated with surgical factors such as incision length and thigh-to-calf ratio. Prevalence and extent of numbness was not significantly associated with SF-36 scores and KSS at the 1-year postoperative period. CONCLUSIONS: There is a high prevalence of numbness around the knee 1 year after MUKA. Surgical incision length and thigh-to-calf ratio was not associated with the extent of numbness. The presence and extent of numbness did not affect functional outcomes scores at the 1-year postoperative period. This study finding allows for accurate preoperative counselling with regards to numbness and its effects for patients undergoing MUKA.

Reliability of the new modified Moro's classification and oblique corridor grading to assess the feasibility of oblique lumbar interbody fusion.

INTRODUCTION: The modified Moro's classification (MMC) of psoas morphology and oblique corridor (OC) grading were recently proposed. Their reliability needs to be tested. METHODS: T2 weighted lumbar disc level axial-cut MRI images of patients with degenerative spondylosis were distributed to five spine surgeons. The inter and intra-rater reliability of MMC and OC grading were calculated based on their ratings. RESULTS: Based on kappa statistics, we inferred that both MMC and OC grading are reliable measures. CONCLUSION: Both MMC and OC grading, in combination, can be used to predict the feasibility of oblique lumbar interbody fusion and aid in patient selection.