Lateral lumbar interbody fusion at L4-L5 has a low rate of complications in appropriately selected patients when using a standardized surgical technique.

Aims: The aim of this study was to reassess the rate of neurological, psoas-related, and abdominal complications associated with L4-L5 lateral lumbar interbody fusion (LLIF) undertaken using a standardized preoperative assessment and surgical technique. Methods: This was a multicentre retrospective study involving consecutively enrolled patients who underwent L4-L5 LLIF by seven surgeons at seven institutions in three countries over a five-year period. The demographic details of the patients and the details of the surgery, reoperations and complications, including femoral and non-femoral neuropraxia, thigh pain, weakness of hip flexion, and abdominal complications, were analyzed. Neurological and psoas-related complications attributed to LLIF or posterior instrumentation and persistent symptoms were recorded at one year postoperatively. Results: A total of 517 patients were included in the study. Their mean age was 65.0 years (SD 10.3) and their mean BMI was 29.2 kg/m2 (SD 5.5). A mean of 1.2 levels (SD 0.6) were fused with LLIF, and a mean of 1.6 (SD 0.9) posterior levels were fused. Femoral neuropraxia occurred in six patients (1.2%), of which four (0.8%) were LLIF-related and two (0.4%) had persistent symptoms one year postoperatively. Non-femoral neuropraxia occurred in nine patients (1.8%), one (0.2%) was LLIF-related and five (1.0%) were persistent at one year. All LLIF-related neuropraxias resolved by one year. A total of 32 patients (6.2%) had thigh pain, 31 (6.0%) were LLIF-related and three (0.6%) were persistent at one year. Weakness of hip flexion occurred in 14 patients (2.7%), of which eight (1.6%) were LLIF-related and three (0.6%) were persistent at one year. No patients had bowel injury, three (0.6%) had an intraoperative vascular injury (not LLIF-related), and five (1.0%) had ileus. Reoperations occurred in five patients (1.0%) within 30 days, 37 (7.2%) within 90 days, and 41 (7.9%) within one year postoperatively. Conclusion: LLIF involving the L4-L5 disc level has a low rate of persistent neurological, psoas-related, and abdominal complications in patients with the appropriate indications and using a standardized surgical technique.

Single-Position Prone Lateral Lumbar Interbody Fusion Increases Operative Efficiency and Maintains Safety in Revision Lumbar Spinal Fusion.

STUDY DESIGN: Multi-centre retrospective cohort study. OBJECTIVE: To evaluate the feasibility and safety of the single-position prone lateral lumbar interbody fusion (LLIF) technique for revision lumbar fusion surgery. BACKGROUND CONTEXT: Prone LLIF (P-LLIF) is a novel technique allowing for placement of a lateral interbody in the prone position and allowing posterior decompression and revision of posterior instrumentation without patient repositioning. This study examines perioperative outcomes and complications of single position P-LLIF against traditional Lateral LLIF (L-LLIF) technique with patient repositioning. METHOD: A multi-centre retrospective cohort study involving patients undergoing 1 to 4 level LLIF surgery was performed at 4 institutions in the US and Australia. Patients were included if their surgery was performed via either: P-LLIF with revision posterior fusion; or L-LLIF with repositioning to prone. Demographics, perioperative outcomes, complications, and radiological outcomes were compared using independent samples t-tests and chi-squared analyses as appropriate with significance set at P <0.05. RESULTS: 101 patients undergoing revision LLIF surgery were included, of which 43 had P-LLIF and 58 had L-LLIF. Age, BMI and CCI were similar between groups. The number of posterior levels fused (2.21 P-LLIF vs. 2.66 L-LLIF, P =0.469) and number of LLIF levels (1.35 vs. 1.39, P =0.668) was similar between groups.Operative time was significantly less in the P-LLIF group (151 vs. 206 min, P =0.004). EBL was similar between groups (150mL P-LLIF vs. 182mL L-LLIF, P =0.31) and there was a trend toward reduced length of stay in the P-LLIF group (2.7 vs. 3.3d, P =0.09). No significant difference was demonstrated in complications between groups. Radiographic analysis demonstrated no significant differences in preoperative or postoperative sagittal alignment measurements. CONCLUSION: P-LLIF significantly improves operative efficiency when compared to L-LLIF for revision lumbar fusion. No increase in complications was demonstrated by P-LLIF or trade-offs in sagittal alignment restoration. LEVEL OF EVIDENCE: Level 4.

Lateral decubitus single position anterior posterior surgery improves operative efficiency, improves perioperative outcomes, and maintains radiological outcomes comparable with traditional anterior posterior fusion at minimum 2-year follow-up.

BACKGROUND CONTEXT: The advantages of lateral single position surgery (LSPS) in the perioperative period has previously been demonstrated, however 2-year postoperative outcomes of this novel technique have not yet been compared to circumferential anterior-posterior fusion (FLIP) at 2-years postoperatively. PURPOSE: Evaluate the safety and efficacy of LSPS versus gold-standard FLIP STUDY DESIGN/SETTING: Multicenter retrospective cohort review. PATIENT SAMPLE: Four hundred forty-two patients undergoing lumbar fusion via LSPS or FLIP OUTCOME MEASURES: Levels fused, operative time, estimated blood loss, perioperative complications, and reasons for reoperation at 30-days, 90-days, 1-year, and 2-years. Radiographic outcomes included lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), PI-LL mismatch, and segmental lumbar lordosis. METHODS: Patients were grouped as LSPS if anterior and posterior portions of the procedure were performed in the lateral decubitus position, and FLIP if patients were repositioned from supine or lateral to prone position for the posterior portion of the procedure under the same anesthetic. Groups were compared in terms of demographics, intraoperative, perioperative and radiological outcomes, complications and reoperations up to 2-years follow-up. Measures were compared using independent samples or paired t-tests and chi-squared analyses with significance set at p<.05. RESULTS: Four hundred forty-two patients met inclusion, including 352 LSPS and 90 FLIP patients. Significant differences were noted in age (62.4 vs 56.9; p≤.001) and smoking status (7% vs 16%; p=.023) between the LSPS and FLIP groups. LSPS demonstrated significantly lower Op time (97.7min vs 297.0 min; p<.001), fluoro dose (36.5mGy vs 78.8mGy; p<.001), EBL (88.8mL vs 270.0mL; p<.001), and LOS (1.91 days vs 3.61 days; p<.001) compared to FLIP. LSPS also demonstrated significantly fewer post-op complications than FLIP (21.9% vs 34.4%; p=.013), specifically regarding rates of ileus (0.0% vs 5.6%; p<.001). No differences in reoperation were noted at 30-day (1.7%LSPS vs 4.4%FLIP, p=.125), 90-day (5.1%LSPS vs 5.6%FLIP, p=.795) or 2-year follow-up (9.7%LSPS vs 12.2% FLIP; p=.441). LSPS group had a significantly lower preoperative PI-LL (4.1° LSPS vs 8.6°FLIP, p=.018), and a significantly greater postoperative LL (56.6° vs 51.8°, p = .006). No significant differences were noted in rates of fusion (94.3% LSPS vs 97.8% FLIP; p=.266) or subsidence (6.9% LSPS vs 12.2% FLIP; p=.260). CONCLUSIONS: LSPS and circumferential fusions have similar outcomes at 2-years post-operatively, while reducing perioperative complications, improving perioperative efficiency and safety.

Single-position circumferential lumbar spinal fusion: an overview of terminology, concepts, rationale and the current evidence base.

PURPOSE: To provide definitions and a conceptual framework for single position surgery (SPS) applied to circumferential fusion of the lumbar spine. METHODS: Narrative literature review and experts' opinion. RESULTS: Two major limitations of lateral lumbar interbody fusion (LLIF) have been (a) a perceived need to reposition the patient to the prone position for posterior fixation, and (b) the lack of a robust solution for fusion at the L5/S1 level. Recently, two strategies for performing single-position circumferential lumbar spinal fusion have been described. The combination of anterior lumbar interbody fusion (ALIF) in the lateral decubitus position (LALIF), LLIF and percutaneous pedicle screw fixation (pPSF) in the lateral decubitus position is known as lateral single-position surgery (LSPS). Prone LLIF (PLLIF) involves transpsoas LLIF done in the prone position that is more familiar for surgeons to then implant pedicle screw fixation. This can be referred to as prone single-position surgery (PSPS). In this review, we describe the evolution of and rationale for single-position spinal surgery. Pertinent studies validating LSPS and PSPS are reviewed and future questions regarding the future of these techniques are posed. Lastly, we present an algorithm for single-position surgery that describes the utility of LALIF, LLIF and PLLIF in the treatment of patients requiring AP lumbar fusions. CONCLUSIONS: Single position surgery in circumferential fusion of the lumbar spine includes posterior fixation in association with any of the following: lateral position LLIF, prone position LLIF, lateral position ALIF, and their combination (lateral position LLIF+ALIF). Preliminary studies have validated these methods.

Postoperative spinal alignment comparison of lateral versus supine patient position L5-S1 anterior lumbar interbody fusion.

PURPOSE: Over the past decade, alternative patient positions for the treatment of the anterior lumbar spine have been explored in an effort to maximize the benefits of direct anterior column access while minimizing the inefficiencies of single or multiple intraoperative patient repositionings. The lateral technique allows for access from L1 to L5 through a retroperitoneal, muscle-splitting, transpsoas approach with placement of a large intervertebral spacer than can reliably improve segmental lordosis, though its inability to be used at L5-S1 limits its overall adoption, as L5-S1 is one of the most common levels treated and where high levels of lordosis are optimal. Recent developments in instrumentation and techniques for lateral-position treatment of the L5-S1 level with a modified anterior lumbar interbody fusion (ALIF) approach have expanded the lateral position to L5-S1, though the positional effect on L5-S1 lordosis is heretofore unreported. The purpose of this study was to compare local and regional alignment differences between ALIFs performed with the patient in the lateral (L-ALIF) versus supine position (S-ALIF). METHODS: Retrospective, multi-center data and radiographs were collected from 476 consecutive patients who underwent L5-S1 L-ALIF (n = 316) or S-ALIF (n = 160) for degenerative lumbar conditions. Patients treated at L4-5 and above with other single-position interbody fusion and posterior fixation techniques were included in the analysis. Baseline patient characteristics were similar between the groups, though L-ALIF patients were slightly older (58 vs. 54 years), with a greater preoperative mean L5-S1 disk height (7.8 vs. 5.8 mm), and with less preoperative slip (6.6 vs. 8.5 mm), respectively. 262 patients were treated with only L-ALIF or S-ALIF at L5-S1 while the remaining 214 patients were treated with either L-ALIF or S-ALIF at L5-S1 along with fusions at other thoracolumbar levels. Lumbar lordosis (LL), L5-S1 segmental lordosis, L5-S1 disk space height, and slip reduction in L5-S1 spondylolisthesis were measured on preoperative and postoperative lateral X-ray images. LL was only compared between single-level ALIFs, given the variability of other procedures performed at the levels above L5-S1. RESULTS: Mean pre- to postoperative L5-S1 segmental lordosis improved 39% (6.6°) and 31% (4.9°) in the L-ALIF and S-ALIF groups, respectively (p = 0.063). Mean L5-S1 disk height increased by 6.5 mm (89%) in the L-ALIF and 6.4 mm (110%) in the S-ALIF cohorts, (p = 0.650). Spondylolisthesis, in those patients with a preoperative slip, average reduction in the L-ALIF group was 1.5 mm and 2.2 mm in the S-ALIF group (p = 0.175). In patients treated only at L5-S1 with ALIF, mean segmental alignment improved significantly more in the L-ALIF compared to the S-ALIF cohort (7.8 vs. 5.4°, p = 0.035), while lumbar lordosis increased 4.1° and 3.6° in the respective groups (p = 0.648). CONCLUSION: Use of the lateral patient position for L5-S1 ALIF, compared to traditional supine L5-S1 ALIF, resulted in at least equivalent alignment and radiographic outcomes, with significantly greater improvement in segmental lordosis in patients treated only at L5-S1. These data, from the largest lateral ALIF dataset reported to date, suggest that-radiographically-the lateral patient position can be considered as an alternative to traditional ALIF positional techniques.

Rate of failure of indirect decompression in lateral single-position surgery: clinical results.

OBJECTIVE: Lateral single-position surgery (LSPS) of the lumbar spine generally involves anterior lumbar interbody fusion (ALIF) performed in the lateral position (LALIF) at L5-S1 with or without lateral lumbar interbody fusion (LLIF) at L4-5 and above, followed by bilateral pedicle screw fixation (PSF) without repositioning the patient. One obstacle to more widespread adoption of LSPS is the perceived need for direct decompression of the neural elements, which typically requires flipping the patient to the prone position. The purpose of this study was to examine the rate of failure of indirect decompression in a cohort of patients undergoing LSPS from L4 to S1. METHODS: A multicenter, post hoc analysis was undertaken from prospectively collected data of patients at 3 institutions who underwent LALIF at L5-S1 with or without LLIF at L4-5 with bilateral PSF in the lateral decubitus position between March 2018 and March 2020. Inclusion criteria were symptoms of radiculopathy or neurogenic claudication, central or foraminal stenosis (regardless of degree or etiology), and indication for interbody fusion at L5-S1 or L4-S1. Patients with back pain only; those who were younger than 18 years; those with tumor, trauma, or suspicion of infection; those needing revision surgery; and patients who required greater than 2 levels of fusion were excluded. Baseline patient demographic information and surgical data were collected and analyzed. The number of patients in whom indirect decompression failed was recorded and each individual case of failure was analyzed. RESULTS: A total of 178 consecutive patients underwent LSPS during the time period (105 patients underwent LALIF at L5-S1 and 73 patients underwent LALIF at L5-S1 with LLIF at L4-5). The mean follow-up duration was 10.9 ± 6.5 months. Bilateral PSF was placed with the patient in the lateral decubitus position in 149 patients, and there were 29 stand-alone cases. The mean case time was 101.9 ± 41.5 minutes: 79.3 minutes for single-level cases and 134.5 minutes for 2-level cases. Three patients (1.7%) required reoperation for failure of indirect decompression. CONCLUSIONS: The rate of failure of indirect decompression in LSPS from L4 to S1 is exceedingly low. This low risk of failure should be weighed against the risks associated with direct decompression as well as the risks of the extra operative time needed to perform this decompression.

The Evaluation of Donor Site Pain After Harvest of Tricortical Anterior Iliac Crest Bone Graft for Spinal Surgery: A Prospective Study.

STUDY DESIGN: A prospective cohort. OBJECTIVE: The aim of this study was to prospectively observe donor site pain, health-related quality-of-life outcomes, and complications following harvest of tricortical anterior iliac crest bone graft (AICBG) for anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: Persistent donor site pain from the anterior iliac crest has been reported to range between 2% and 40%. This morbidity has led surgeons to consider interbody alternatives for ACDF, which carry additional costs. METHODS: We prospectively enrolled 50 patients from 2 tertiary care centers over the course of 1 year observing complications and patient-reported outcomes. Patients filled out SF-12 and numeric rating scale (NRS) for pain in the arm, neck, and donor site pre-operatively and at 1 week, 2 weeks, 6 weeks, 3 to 6 months, and 1 year postoperatively. Outcomes were compared with a control group undergoing ACDF with allograft or Polyether ether ketone cages at 1 year. RESULTS: The mean ±â€ŠSD donor site pain at 1 week was 5.6 ±â€Š2.8 but decreased to 2.2 ±â€Š2.4 at 6 weeks and 1.1 ±â€Š1.8 at 1 year (P < 0.001). Including the 3 patients who were lost to follow-up, 10% of patients may have experienced persistent moderate or worse pain at 1 year. Linear regression analysis demonstrated that preoperative opioid use was an independent risk factor for increased donor site pain at 1 and 2 weeks (P < 0.05). There were no differences in outcomes at 1 year compared with the nonautograft group. There were 2 (4%) minor wound complications, both treated successfully with oral antibiotics. CONCLUSION: Tricortical AICBG for ACDF is not associated with major complications and only 4% of patients (potentially, maximum of 10%) experienced moderate, persistent donor site pain at 1 year. There is no difference in health-related outcomes between patients who have autograft with those who did not at 1 year. Preoperative opioid use is associated with increased donor site pain within the first 2 weeks postoperatively but not in the long term. At 6 weeks postoperatively, patients can expect the majority of their donor site pain to be resolved. LEVEL OF EVIDENCE: 2.

Operative treatment of cervical myelopathy: cervical laminoplasty.

Cervical spondylotic myelopathy (CSM) is a degenerative process which may result in clinical signs and symptoms which require surgical intervention. Many treatment options have been proposed with various degrees of technical difficulty and technique sensitive benefits. We review laminoplasty as a motion-sparing posterior decompressive method. Current literature supports the use of laminoplasty for indicated decompression. We also decribe our surgical technique for an open-door, or "hinged", laminoplasty.

Does smoking influence fusion rates in posterior cervical arthrodesis with lateral mass instrumentation?

BACKGROUND: Smoking is associated with reduced fusion rates after anterior cervical decompression and arthrodesis procedures. Posterior cervical arthrodesis procedures are believed to have a higher fusion rate than anterior procedures. QUESTIONS/PURPOSES: We asked whether smoking (1) would reduce the fusion rate in posterior cervical procedures; and (2) be associated with increased pain, decreased activity level, and a decreased rate of return of work as compared with nonsmokers. METHODS: We retrospectively reviewed 158 patients who had a posterior cervical fusion with lateral mass instrumentation and iliac crest bone grafting between 2003 and 2008. Fusion rates and Odom Criteria grades were compared among smokers and nonsmokers. The minimum followup was 3 months (average, 14.5 months; range, 3-72 months). RESULTS: Smokers and nonsmokers had similar fusion rates (100%). Although 80% of patients had Odom Criteria Grade I or II, smokers were five times more likely to have Grade III or IV with considerable limitation of physical activity. Age, gender, and diagnosis did not influence fusion rates or the Odom Criteria grade. CONCLUSIONS: In contrast to the effect of smoking on anterior cervical fusion, we found smoking did not decrease posterior cervical fusion with lateral mass instrumentation and iliac crest bone grafting. Posterior cervical fusion with lateral mass instrumentation should be considered over anterior procedures in smokers if the abnormality can appropriately be addressed from a posterior approach. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Anatomic and structural evaluation of the hip: a cross-sectional imaging technique combining anatomic and biomechanical evaluations.

To describe a technique of cross-sectional imaging of the adult hip designed to evaluate for anatomic anomalies that may predispose to internal derangement in addition to the routine anatomic assessment. Magnetic resonance (MR) imaging, MR arthrography, and multidetector computed tomography (MDCT) scanning protocols utilize high-resolution imaging, and the surrounding anatomy is also assessed using these scanning techniques. Various measurements may be obtained to assess the overarching anatomic configuration including the caput caput collum diaphysis angle, the femoral angle of torsion, the acetabular angle of torsion, the center edge angle, and the femur length.

The function of the hip capsular ligaments: a quantitative report.

PURPOSE: Our purpose was to analyze the anatomy and quantitative contributions of the hip capsular ligaments. METHODS: The stabilizing roles of the medial and lateral arms of the iliofemoral ligament, pubofemoral ligament, and ischiofemoral ligament were examined in 12 matched pairs of fresh-frozen cadaveric hips (6 male and 6 female hips). The motion at the hip joint was measured in internal and external rotation through ranges of motion from 30 degrees flexion to 10 degrees extension along a neutral swing path. The motion was standardized by use of frame stabilization and motion tracking. RESULTS: There is a clear and consistent ligamentous pattern within the hip corresponding to a distinct function and contribution to internal and external rotation. On releasing the ischiofemoral ligament, the greatest gain in range of motion was that of internal rotation. The largest increase of motion by releasing the pubofemoral ligament was observed in external rotation, especially during extension. The release of the medial and lateral arms of the iliofemoral ligament each gave the greatest increase of motion in external rotation, with the lateral arm release providing more range of motion in flexion and in a neutral position. The lateral arm release also showed a significant motion increase in internal rotation, primarily in extension. CONCLUSIONS: The ischiofemoral ligament controls internal rotation in flexion and extension. The lateral arm of the iliofemoral ligament has dual control of external rotation in flexion and both internal and external rotation in extension. The pubofemoral ligament controls external rotation in extension with contributions from the medial and lateral arms of the iliofemoral ligament. Together, these findings can have significant clinical applications. CLINICAL RELEVANCE: When abnormal muscular and osseous pathology can be eliminated as a cause of instability or restrictive range of motion, the understanding of the independent functions of the hip ligaments will aid in defining accurate assessment and nonsurgical and arthroscopic treatment techniques.

Clinical examination of the athletic hip.

This article provides a succinct and complete method for the clinical evaluation of the hip. Included are descriptions of examination tests as well as their relationships to possible pathology of the hip. The examination is divided into five stages: seated, standing, supine, lateral, and prone; with a total of 11 assessment points. The method for evaluation outlined will assist physicians in determining the location and etiology of presenting hip pathologies. As with any examination, practice and repetition are essential to gain an appreciation of what constitutes a normal as well as an abnormal examination.