Arthroscopy-Assisted Reduction in the Management of Isolated Medial Malleolar Fracture.

PURPOSE: To evaluate the feasibility of arthroscopic reduction percutaneous fixation (ARPF) in the treatment of isolated medial malleolar fracture and compare the results with those of conventional open reduction internal fixation (ORIF). METHODS: This prospective study enrolled 77 patients with isolated medial malleolar fracture between November 2011 and February 2016. The patients were assigned to the ARPF (n = 34) and ORIF (n = 43) groups. The Olerud-Molander ankle score (OMAS), ankle range of motion (ROM), visual analog scale, and radiographic evaluation were determined at the scheduled follow-up. RESULTS: In the ARPF group, 11 of 34 patients (32.4%) had chondral lesions. Tears of the deltoid ligament and anterior inferior tibiofibular ligament were noted in 3 (8.8%) and 15 (44.1%) patients, respectively. The mean follow-up was 5 years. The mean OMAS was higher in the ARPF group than in the ORIF group. The differences were statistically significant at 6 months (mean ± standard deviation, 80.2 ± 4.0 for ARPF vs 77.2 ± 4.1 for ORIF, P = .005) and 1 year (92.9 ± 4.9 vs 88.1 ± 4.6, P < .001), but not at the latest follow-up (P = .081). Ankle ROM was markedly improved in the ARPF group, unlike in the ORIF group at 6 months (dorsiflexion, P = .025; plantarflexion, P < .001) and 1 year (dorsiflexion and plantarflexion, P < .001). The improvement remained at the latest follow-up in plantarflexion (P = .001) but not in dorsiflexion (P = .354). CONCLUSIONS: Arthroscopy-assisted reduction is a feasible alternative modality with superior short-term outcomes for treating isolated medial malleolar fracture, but its superiority may be attenuated in the intermediate term. LEVEL OF EVIDENCE: Level III, comparative study.

Effect of pure muscle retraction on multifidus injury and atrophy after posterior lumbar spine surgery with 24 weeks observation in a rabbit model.

PURPOSE: To evaluate the effect of pure muscle retraction on multifidus injury and atrophy. MATERIALS AND METHODS: Sixty-three adult New Zealand white rabbits were divided evenly into three groups: 1-h retraction (group R1), 2-h retraction (R2), and sham surgery (C). The multifidus muscle was evaluated using magnetic resonance imaging (MRI) and histology after 3 and 48 h, and 1, 3, 6, 12, and 24 weeks after surgery. RESULTS: Multifidus muscle injury and atrophy were not observed in group C, but were obvious in groups R1 and R2. Edema, necrosis, and inflammation mainly occurred in the first week postoperatively, and were more severe in R2 than in R1 (P < 0.01). Muscle fiber regeneration began at week 1, fibrotic changes mainly occurred at weeks 3 and 6, and fat degeneration became obvious at weeks 12 and 24 postoperatively. The fibrosis and fat degeneration scores of R2 were higher than those of R1 (P < 0.01). Decreased acetylcholine activity and granular degeneration of the neuromuscular junction were observed in both retraction groups, but was more severe in R2 than in R1 (P < 0.01). CONCLUSION: Muscle retraction was an important factor not only for multifidus injury, but also for long-term multifidus atrophy after posterior lumbar surgery; a longer retraction time caused more severe multifidus injury and atrophy. Muscle fibers can be regenerated postoperatively, and denervation might be the reason for muscle atrophy.

PHD/HIF-1 upregulates CA12 to protect against degenerative disc disease: a human sample, in vitro and ex vivo study.

Intervertebral disc degeneration is a major cause of low back pain. The nucleus pulposus (NP) is an important intervertebral disc component. Recent studies have shown that carbonic anhydrase 12 (CA12) is a novel NP marker. However, the mechanism by which CA12 is regulated and its physiological function are unclear. In our study, CA12, hypoxia-inducible factor 1α (HIF-1α) and HIF-2α expression levels were examined in 81 human degenerated NP samples using real-time RT-PCR, immunohistochemistry and western blot. Rat NP cells were cultured in a hypoxic environment, and hypoxia-induced CA12 expression was examined. Rat NP cells were treated with HIF-1α siRNA or the prolyl hydroxylase (PHD) inhibitor dimethyloxalylglycine (DMOG) to evaluate the role of PHD/HIF-1 in regulating CA12 expression. Rat NP cells were treated with CA12 siRNA to determine the function of CA12. A rat ex vivo model was established to confirm that PHD, HIF-1, and CA12 have important roles in disc degeneration. We found that CA12 was significantly downregulated in degenerated human NP samples at the mRNA and protein levels. CA12 expression sharply increased by ~30-fold in response to hypoxia. The expression of HIF-1α, but not HIF-2α, also decreased in degenerated human NP samples and was positively correlated with CA12 expression. HIF-1α knockdown under hypoxia reduced the CA12 mRNA and protein expression levels. DMOG treatment increased HIF-1α and CA12 expression. CA12 knockdown significantly inhibited anabolic protein expression, whereas catabolic enzymes remained unchanged. The ex vivo experiments supported our in vitro studies of the role of PHD/HIF-1/CA12. In conclusion, CA12 is downregulated in degenerated NPs, and its expression may be regulated by the PHD/HIF-1 axis. Decreased CA12 expression may lead to decreased extracellular matrix synthesis, which contributes to degenerative disc disease progression.

The NLRP3/Caspase-1/Interleukin-1ß Axis Is Active in Human Lumbar Cartilaginous Endplate Degeneration.

BACKGROUND: Modic changes are the MRI signal changes of degenerative lumbar vertebral endplate and which lead to or accelerate intervertebral disc degeneration. NLRP3, caspase-1, and interleukin-1ß (IL-1ß) play a pivotal role in the pathogenesis of many inflammatory diseases, such as osteoarthritis. However, the roles of IL-1ß and its activators caspase-1 and NLRP3 are unclear in the degenerative endplate. QUESTIONS/PURPOSES: We asked: (1) What are the degenerative changes of the histologic features and chondrogenic markers' gene expressions between the cartilaginous endplates of patients with Modic changes and trauma (control)? (2) How does the NLRP3/caspase-1/IL-1ß axis in the cartilaginous endplates of patients with Modic changes compare with control (trauma) specimens? METHODS: Surgical specimens of cartilaginous endplates were divided into Modic changes (n = 56) and the trauma control (n = 16) groups. Hematoxylin and eosin and safranin O staining of cartilaginous endplate tissues were done to evaluate the extracellular matrix. Reverse transcription-polymerase chain reaction was performed on these tissues to investigate mRNA expression of type II collagen (Col II), SOX-9, matrix metalloproteinase-3, and a disintegrin like and metalloproteinase thrombospondin type I motifs-5. NLRP3, caspase-1, and IL-1ß were evaluated by reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: Hematoxylin and eosin and safranin O staining showed the extracellular matrix degraded in the cartilaginous endplates of patients with Modic changes but not in the control cartilaginous endplates. Chondrogenic Col II (p = 0.024) and SOX9 (p = 0.053) were downregulated in the Modic changes group compared with the control group. In contrast to the control group, the transcriptional levels of NLRP3 (p < 0.001), caspase-1 (p = 0.054), and IL-1ß (p = 0.001) were all upregulated in the Modic changes group. CONCLUSIONS: The expression of NLRP3, caspase-1, and IL-1ß was upregulated in the patients with low back pain and Modic changes on MRI compared with patients with vertebral burst fracture without degenerative changes on MRI. The data suggest the NLRP3/caspase-1/IL-1ß axis may be implicated in lumbar cartilaginous endplate degeneration. CLINICAL RELEVANCE: The NLRP3/caspase-1/IL-1ß axis is active in cartilaginous endplates of patients with Modic changes and inflammatory cascades can exacerbate the cartilaginous endplate degeneration which may act as a trigger for intervertebral disc degeneration and low back pain. If these findings can be confirmed by others, we hope that new and effective therapy could be developed directed against this target.

Iatrogenic injury to the erector spinae during posterior lumbar spine surgery: underlying anatomical considerations, preventable root causes, and surgical tips and tricks.

The approach-related morbidity resulting from iatrogenic erector spinae injury in posterior lumbar surgery has become an increasing concern for spine surgeons. Many studies have explained the injury mechanisms and reported new surgical approaches to prevent this iatrogenic injury from their own point of views, but there is still no systemic information for a thorough understanding of this iatrogenic erector spinae injury that may give spine surgeons practical advices in their individual operations. We consequently reviewed the literature on the anatomy of erector spinae, causes of injury, and relative minimally invasive approaches. We found that the local anatomic structures make the erector spinae vulnerable to injury during posterior lumbar surgery, especially the medial multifidus which is innervated only by the medial branch of the dorsal ramus, with no intersegmental nerve supply as in the other paraspinal muscles, and the injury factors mainly include dissection, retraction, denervation, and immobility. Studies suggest that the goal of prevention is to preserve the physiological structure of erector spinae and to avoid or limit the injury causes: approaches through spatium intermusculare and approaches with endoscope and tubular retractor system can prevent the erector spinae from injury by less dissection and retraction; non-fusion techniques may prevent the erector spinae from disuse atrophy by preserving the segmental motion and the adjacent erector spinae activity.

[Analysis of the causes of cage subsidence after oblique lateral lumbar interbody fusion].

OBJECTIVE: To observe the cage subsidence after oblique lateral interbody fusion (OLIF) for lumbar spondylosis, summarize the characteristics of the cage subsidence, analyze causes, and propose preventive measures. METHODS: The data of 144 patients of lumbar spine lesions admitted to our hospital from October 2015 to December 2018 were retrospectively analyzed. There were 43 males and 101 females, and the age ranged from 20 to 81 years old, with an average of (60.90±10.06) years old. Disease types:17 patients of lumbar intervertebral disc degenerative disease, 12 patients of giant lumbar disc herniation, 5 patients of discogenic low back pain, 33 patients of lumbar spinal stenosis, 26 patients of lumbar degenerative spondylolisthesis, 28 patients of lumbar spondylolisthesis with spondylolisthesis, 11 patients of adjacent vertebral disease after lumbar internal fixation, 7 patients of primary spondylitis in the inflammatory outcome stage, and 5 patients of lumbar degenerative scoliosis. Preoperative dual-energy X-ray bone mineral density examination showed 57 patients of osteopenia or osteoporosis, and 87 patients of normal bone density. The number of fusion segments:124 patients of single-segment, 11 patients of two-segment, 8 patients of three-segment, four-segment 1 patient. There were 40 patients treated by stand-alone OLIF, and 104 patients by OLIF combined with posterior pedicle screw. Observed the occurrence of fusion cage settlement after operation, conducted monofactor analysis on possible risk factors, and observed the influence of fusion cage settlement on clinical results. RESULTS: All operations were successfully completed, the median operation time was 99 min, and the median intraoperative blood loss was 106 ml. Intraoperative endplate injury occurred in 30 patients and vertebral fracture occurred in 5 patients. The mean follow-up was (14.57±7.14) months from 6 to 30 months. During the follow-up, except for the patients of primary lumbar interstitial inflammation and some patients of lumbar spondylolisthesis with spondylolisthesis, the others all had different degrees of cage subsidence. Cage subsidence classification:119 patients were normal subsidence, and 25 patients were abnormal subsidence (23 patients were gradeⅠ, and 2 patients were gradeⅡ). There was no loosening or rupture of the pedicle screw system. The height of the intervertebral space recovered from the preoperative average (9.48±1.84) mm to the postoperative average (12.65±2.03) mm, and the average (10.51±1.81) mm at the last follow-up. There were statistical differences between postoperative and preoperative, and between the last follow-up and postoperative. The interbody fusion rate was 94.4%. The low back pain VAS decreased from the preoperative average (6.55±2.2 9) to the last follow-up (1.40±0.82), and there was statistically significant different. The leg pain VAS decreased from the preoperative average (4.72±1.49) to the final follow-up (0.60±0.03), and the difference was statistically significant (t=9.13, P<0.000 1). The ODI index recovered from the preoperative average (38.50±6.98)% to the latest follow-up (11.30±3.27)%, and there was statistically significant different. The complication rate was 31.3%(45/144), and the reoperation rate was 9.72%(14/144). Among them, 8 patients were reoperated due to fusion cage subsidence or displacement, accounting for 57.14%(8/14) of reoperation. The fusion cage subsidence in this group had obvious characteristics. The monofactor analysis showed that the number of abnormal subsidence patients in the osteopenia or osteoporosis group, Stand-alone OLIF group, 2 or more segments fusion group, and endplate injury group was higher than that in the normal bone mass group, OLIF combined with pedicle screw fixation group, single segment fusion group, and no endplate injury group, and the comparison had statistical differences. CONCLUSION: Cage subsidence is a common phenomenon after OLIF surgery. Preoperative osteopenia or osteoporosis, Stand-alone OLIF, 2 or more segments of fusion and intraoperative endplate injury may be important factors for postoperative fusion cage subsidence. Although there is no significant correlation between the degree of cage subsidence and clinical symptoms, there is a risk of cage migration, and prevention needs to be strengthened to reduce serious complications caused by fusion of cage subsidence, including reoperation.

[Comparison of clinical effect and muscle injury imaging between oblique lateral lumbar interbody fusion and transforaminal lumbar interbody fusion in the treatment of single-segment degenerative lumbar spinal stenosis].

OBJECTIVE: To compare the efficacy and muscle injury imaging between oblique lateral lumbar interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in the treatment of single-segment degenerative lumbar spinal stenosis. METHODS: The clinical data of 60 patients with single-segment degenerative lumbar spinal stenosis who underwent surgical treatment from January 2018 to October 2019 was retrospectively analyzed. The patients were divided into OLIF groups and TLIF group according to different surgical methods. The 30 patients in the OLIF group were treated with OLIF plus posterior intermuscular screw rod internal fixation. There were 13 males and 17 females, aged from 52 to 74 years old with an average of (62.6±8.3) years old. And 30 patients in the TLIF group were treated with TLIF via the left approach. There were 14 males and 16 females, aged from 50 to 81 years old with an average of (61.7±10.4) years old. General data including operative time, intraoperative blood loss, postoperative drainage volume, and complications were recorded for both groups. Radiologic data including disc height (DH), the left psoas major muscle, multifidus muscle, longissimus muscle area, T2-weighted image hyperintensity changes and interbody fusion or nonfusion were observed. Laboratory parameters including creatine kinase (CK) values on postoperative 1st and 5th days were analyzed. Visual analogue scale(VAS) and Oswestry disability index(ODI) were used to assess clinical efficacy. RESULTS: There was no significant difference in the operative time between two groups(P>0.05). The OLIF group had significantly less intraoperative blood loss and postoperative drainage volume compared to the TLIF group(P<0.01). The OLIF group also had DH better recovery compared to the TLIF group (P<0.05). There were no significant differences in left psoas major muscle area and the hyperintensity degree before and after the operation in the OLIF group (P>0.05). Postoperativly, the area of the left multifidus muscle and longissimus muscle, as well as the mean of the left multifidus muscle and longissimus muscle in the OLIF group, were lower than those in the TLIF group (P<0.05) .On the 1st day and the 5th day after operation, CK level in the OLIF group was lower than that in the TLIF group(P<0.05). On the 3rd day after operation, the VAS of low back pain and leg pain in the OLIF group were lower than those in the TLIF group (P<0.05). There were no significant differences in the ODI of postoperative 12 months, low back and leg pain VAS at 3, 6, 12 months between the two groups(P>0.05). In the OLIF group, 1 case of left lower extremity skin temperature increased after the operation, and the sympathetic chain was considered to be injured during the operation, and 2 cases of left thigh anterior numbness occurred, which was considered to be related to psoas major muscle stretch, resulting in a complication rate of 10% (3/30). In the TLIF group, one patient had limited ankle dorsiflexion, which was related to nerve root traction, two patients had cerebrospinal fluid leakage, and the dural sac was torn during the operation, and one patient had incision fat liquefaction, which was related to paraspinal muscle dissection injury, resulting in a complication rate of 13% (4/30). All patients achieved interbody fusion without cage collapse during the 6- month follow-up. CONCLUSION: Both OLIF and TLIF are effective in the treatment of single-segment degenerative lumbar spinal stenosis. However, OLIF surgery has obviously advantages, including less intraoperative blood loss, less postoperative pain, and good recovery of intervertebral space height. From the changes in laboratory indexes of CK and the comparison of the left psoas major muscle, multifidus muscle, longissimus muscle area, and high signal intensity of T2 image on imaging, it can be seen that the degree of muscle damage and interference of OLIF surgery is lower than that of TLIF.

[Application of oblique lateral interbody fusion in the treatment of lumbar intervertebral disc degeneration in patients with Modic change and endplate sclerosis].

OBJECTIVE: To explore the feasibility and clinical effect of Stand-alone oblique lateral interbody fusion (OLIF) in the treatment of lumbar intervertebral disc degeneration with Modic changes and endplate sclerosis. METHODS: A retrospective analysis was performed on 16 cases with lumbar intervertebral disc degeneration with Modic changes and endplate sclerosis admitted to three medical centers from January 2015 to December 2018. There were 6 males and 10 females, the age ranged from 45 to 67 years old with an average of (55.48±8.07) years old, the medical history ranged from 36 to 240 months with an average of (82.40±47.68) months. The lesion sites included L2,3 in 2 cases, L3,4 in 5 cases, and L4,5 in 9 cases. All patients presented with chronic low back pain with lower limb neurological symptoms in 3 cases. All patients were treated by Stand-alone oblique lateral lumbar interbody fusion. Clinical and radiological findings and complications were observed. RESULTS: There was no vascular injury, endplate injury and vertebral fracture during the operation. The mean incision length, operation time, and intraoperative blood loss were(4.06±0.42) cm, (45.12±5.43) min, (33.40±7.29) ml, respectively. The mean visual analogue scale (VAS) of the incision pain was (1.14±0.47) at 72 hours after operation. There was no incision skin necrosis, poor incision healing or infection in patients. Sympathetic chain injury occurred in 1 case, anterolateral pain and numbness of the left thigh in 2 cases, and weakness of the left iliopsoas muscle in 1 case, all of which were transient injuries with a complication rate of 25%(4/16). All 16 patients were followed up from 12 to 36 months with an average of (20.80±5.46) months. The intervertebral space height was significantly recovered after operation, with slight lost during the follow-up. Coronal and sagittal balance of the lumbar spine showed good improvement at the final follow-up. There was no obvious subsidence or displacement of the cage, and the interbody fusion was obtained. At the final follow-up, Japanese Orthopaedic Association(JOA) score and Oswestry disability index(ODI) were significantly improved. CONCLUSION: As long as the selection of case is strict enough and the preoperative examination is sufficients, the use of Stand-alone OLIF in the treatment of lumbar intervertebral disc degeneration with Modic changes and endplate sclerosis has a good results, with obvious clinical advantages and is a better surgical choice.

[Analysis of the causes and clinical results of vertebral fracture during oblique lateral lumbar interbody fusion].

OBJECTIVE: To analyze the causes of vertebral fracture during oblique lateral interbody fusion in the treatment of lumbar spondylopathy, summarize the clinical results, and propose preventive measures. METHODS: Retrospective analysis was made on the data of 8 cases of lumbar spondylopathy and vertebral fracture treated by oblique lateral interbody fusion in three medical centers from October 2014 to December 2018. All were female, aged from 50 to 81 years with an average of 66.4 years. Disease types included 1 case of lumbar degenerative disease, 3 cases of lumbar spinal stenosis, 2 cases of lumbar degenerative spondylolisthesis and 2 cases of lumbar degenerative scoliosis. Preoperative dual energy X-ray bone mineral density test showed that 2 cases had T-value >-1 SD, 2 cases had T-value -1 to -2.5 SD, and 4 cases had T-value <-2.5 SD. Single segment fusion was in 5 cases, two segment fusion in 1 case and three segment fusion in 2 cases. Four cases were treated with OLIF Stand-alone and 4 cases were treated with OLIF combined with posterior pedicle screw fixation. Postoperative imaging examination showed vertebral fracture, and all of them were single vertebral fracture. There were 2 cases of right lower edge fracture of upper vertebral body at fusion segment, 6 cases of lower vertebral body fracture at fusion segment, and 6 cases with endplate injury and fusion cage partially embedded in vertebral body. Three cases of OLIF Stand-alone were treated with pedicle screw fixation via posterior intermuscular approach, while one case of OLIF Stand-alone and four cases of OLIF combined with posterior pedicle screw fixation were not treated specially. RESULTS: The 5 cases of initial operation and 3 cases of reoperation did not show wound skin necrosis or wound infection. The follow-up time was from 12 to 48 months with an average of 22.8 months. Visual analogue scale (VAS) of low back pain was preoperative decreased from 4 to 8 points (averagely 6.3 points) and postoperative 1 to 3 points (averagely 1.7 points) at the final follow-up. Oswestry disability index (ODI) was preoperative 39.7% to 52.4% (averagely 40.2%), and postoperative 7.9% to 11.2% (averagely 9.5%) at the final follow-up. During the follow-up, there was no loosening or fracture of the pedicle screw system, and no lateral displacement of the fusion cage;however, the fusion cage at the vertebral fracture segment had obvious subsidence. The intervertebral space height of vertebral fracture segment was preoperaive 6.7 to 9.2 mm (averagely 8.1 mm), and postoperative 10.5 to 12.8 mm (averagely 11.2 mm). The improvement rate after operation was 37.98% compared to preoperative. The intervertebral space height at final follow-up was 8.4 to 10.9 mm (averagely 9.3 mm), and the loss rate was 16.71% compared with that after operation. At the final follow-up, interbody fusion was achieved in all cases except for one that could not be identified. CONCLUSION: The incidence of vertebral fracture during oblique lateral interbody fusion in the treatment of lumbar spondylopathy is lower, and there are many reasons for fracture, including preoperative bone loss or osteoporosis, endplate injury, irregular shape of endplate, excessive selection of fusion cage, and osteophyte hyperplasia at the affected segment. As long as vertebral fracture is found in time and handled properly, the prognosis is well. However, it still needs to strengthen prevention.

Quantitative MRI analysis of the surface area, signal intensity and MRI index of the central bright area for the evaluation of early adjacent disc degeneration after lumbar fusion.

PURPOSE: The aim of this study was to evaluate early ASD at short-term follow-up in fused and unoperated patients with degenerative disc disease, using quantitative magnetic resonance imaging (MRI) analysis of the area, signal intensity and their product, i.e., MRI index of the central bright area of the disc as well as measures of intervertebral disc height and Pfirrmann grading scale. The further purpose was to determine whether fusion accelerates ASD compared with non-surgical treatment in short-term follow-up. METHODS: One hundred and eight chronic low back patients diagnosed as L4/L5 degeneration undertook either one-level instrumented posterior lumbar interbody fusion or conservative treatment. They were followed up for about 1 year. Finally 46 fused and 45 conservatively treated patients with MRI follow-up were included. Pre- and post-treatment MRIs were compared to determine the progression of disc degeneration at the two cranial adjacent segments. RESULTS: The area, signal intensity and MRI index of the central bright area of the adjacent discs decreased in the operated and unoperated groups from pre-treatment to follow-up, except for an insignificant decrease of signal intensity at the second adjacent segment in the unoperated group. The changes in these parameters were statistically greater at the first than the second adjacent segment in the fused group, but not in the unoperated group. And the changes in the fused group were more pronounced than those at both neighbouring levels in the unoperated group. However, the Pfirrmann grading scale and intervertebral disc height did not detect any changes at adjacent discs in either group. CONCLUSIONS: Decrease in the parameters of quantitative MRI analysis indicated early degeneration at discs adjacent to lumbar spinal fusion. Fusion had an independent effect on the natural history of ASD during short-term follow-up. Continued longitudinal follow-up is required to determine whether these MRI changes lead to pathologic changes.

Comparison of Oblique Lateral Interbody Fusion (OLIF) and Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) for Treatment of Lumbar Degeneration Disease: A Prospective Cohort Study.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: To assess the differences in the clinical and radiological outcomes between oblique lateral interbody fusion (OLIF) and minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). SUMMARY OF BACKGROUND DATA: Nowadays, there is still a controversy regarding whether OLIF is superior to MI-TLIF in the management of degenerative lumbar disease. METHODS: Between August 3, 2019 and February 3, 2020, 137 patients were assigned to OLIF or MI-TLIF at their request and the surgeon's discretion: 71 in the OLIF group and 66 in the MI-TLIF group. The perioperative data, patient-reported outcomes, radiographic outcomes, and complications were compared between the two groups. RESULTS: The OLIF group showed shorter operation time (110.5 vs.183.8 minutes, P < 0.001), lesser estimated blood loss (123.1 vs. 232.0 mL, P < 0.001), shorter length of hospital stay (5.5 vs. 6.7 days, P < 0.001), and lower serum creatine kinase (CK) (1 day postoperatively) (376.0 vs. 541.8 IU/L, P < 0.01) than that of MI-TLIF group. Both groups showed no significant differences in the visual analog scale (VAS) scores of lower back and leg pain and the Oswestry Disability Index (ODI) scores preoperatively and at 1, 3, and 12 months postoperatively, respectively (P > 0.05). Compared with the MI-TLIF group, the OLIF group showed better restoration of disc height (DH) (4.7/4.6/4.7 vs. 3.7/3.7/3.7 mm, P < 0.01) and lumbar lordosis angle (LLA) (10.5°/10.8°/11.1° vs. 5.8°/5.7°/5.3°, P < 0.001), but not the value of segmental lordosis angle (SLA) (P > 0.05) at 1 day, 1 month, and 1 year postoperatively, respectively. The complication rate of OLIF was higher than that of MI-TLIF (29.4% vs. 9.7%, P < 0.01). CONCLUSION: Compared with MI-TLIF, OLIF showed similar results in terms of patient-reported outcomes, restoration of SLA and fusion rate, and superior results with respect to restoration of DH and LLA, operation time, estimated blood loss, length of hospital stay, and serum CK levels (1 day postoperatively). Even though the complication rate of OLIF is higher than that of MI-TLIF, it does not bring persistent and substantial damage to the patients.Level of Evidence: 3.

Spontaneous epidural hematoma of thoracic spine presenting as Brown-Séquard syndrome: report of a case with review of the literature.

BACKGROUND: Spontaneous spinal epidural hematoma (SSEH) is an uncommon clinical entity. It produces a severe neurological deficit and prompt decompression is usually the first choice of treatment. Brown-Séquard syndrome is commonly seen in the setting of spinal trauma or an extramedullary spinal neoplasm, but rarely caused by SSEH. METHODS: Case report and literature review. FINDINGS: A previously healthy man presented with Brown-Séquard syndrome below T5-T6 cord segment secondary to spontaneous epidural hematoma. He opted for conservative treatment, which was followed by rapid resolution. CONCLUSIONS: Although Brown-Séquard syndrome as a presenting feature of SSEH is rare, it does exist in exceptional case, which should be taken into consideration for differential diagnosis. Prompt surgical decompression is an absolute surgical indication widely accepted for patient with progressive neurological deficit. However, SSEH presenting with incomplete neurological insult such as Brown-Séquard syndrome might have a benign course. Successful non-operative management of this problem does not make it a standard of care, and surgical decompression remains the standard treatment for SSEH.

[Current advances in research of semaphorin 3A:a potential target for the treatment of nospecific low back pain].

Nonspecific low back pain is closely associated with afferent nerve ingrowth into degenerated IVDs and increasing the inflammatory response. Members of the class 3 semaphorins signal their response through two prominent receptors; the NRP (Neuropilin-1) and the Plexin A. Sema3A (Semaphorin3A) is primarily known for their role in modulating neuronal survival as well as neurite outgrowth and guidance via regulation of Sema3A-NRP-1-plexinA signal pathway. Also, sema3A is shown to be conductive to innervate the inner painful degenerated IVDs (Intervertebral discs). Furthermore, sema3A is thought to act as a barrier to endothelial cells survival and migration on vascular endothelial growth factor (VEGF) and inhibition of KLF5-induced (Krüppel-like factor 5) inflammatory mediators within degenerated IVDs. Therefore, Sema3A produce a new perspective of dual-action therapeutic agent for attenuating the regulator of innervation and angiogenesis into degenerated IVDs and inhibition of KLF5-induced inflammation.

Anteroinferior Psoas Technique for Oblique Lateral Lumbar Interbody Fusion.

Oblique lateral lumbar interbody fusion (OLIF) has been extensively used, with satisfactory outcomes for the treatment of degenerative lumbar disease. This article aims to demonstrate a modified lateral approach, also known as the anteroinferior psoas (AIP) technique for OLIF, which is expected to enhance security by operating under direct vision. The core procedures of our technique are as follows. First, a minimal skin incision is recommended 2 cm backward compared with the normal incision of OLIF, facilitating the oblique placement of the working channel and the orthogonal maneuver for the cage placement. Second, two special custom-made retractors, as an alternative to the index finger, are used to pull the psoas muscle to the dorsal side and pull the abdominal organs together with extraperitoneal fate to the ventral side under direct visualization, making the exposure of the working channel convenient and safe and avoiding radiation exposure. Third, the anterior border of the psoas is bluntly dissected and retracted backwards, obviously enlarging the retroperitoneal anatomic corridor and then expanding clinical indications of OLIF. The benefits of this technique include that it has a short learning curve, satisfactory clinical outcomes, and low risk of perioperative complications.

[Short-segment pedicle screw fixation combined with vertebroplasty for the treatment of Kümmell disease with kyphosis].

OBJECTIVE: To explore the clinical effects of posterior short-segment pedicle screw internal fixation combined with vertebroplasty for the treatment of Kümmell disease with kyphosis. METHODS: Twenty-four patients with Kümmell disease complicated with kyphosis treated by posterior short-segment pedicle screw internal fixation combined with vertebroplasty from January 2016 to December 2018 were retrospectively analyzed, including 6 males and 18 females, aged 63 to 85 (73.1±6.5) years old. The clinical effect was evaluate by visual analogue scale (VAS), Oswestry Disability Index (ODI), the anterior height of injured vertebral body, and the sagittal Cobb angle of the affected segment beforeoperation, at 3 days and final follow up after operation. And the surgical complications were observed. RESULTS: All 24 patients were followed up from 12 to 24 months with an average of (15.5±3.2) months. The VAS score was decreased from 5.21±1.06 preoperatively to 2.38±0.58 at 3 days postoperatively and 1.71±0.75 at final follow-up;ODI was decreased from (50.4±13.5)% preoperatively to (20.9±8.0)% at 3 days postoperatively and (16.7±9.6)% at final follow-up;the anterior height of injured vertebral body was restored from (8.0±4.2) mm before surgery to (18.1±5.0) mm at 3 days after surgery and (16.8±5.1) mm at final follow up;the sagittal Cobb angle of affected segment was decreased from (19.5±6.3)° preoperatively to (7.6±2.1)° at 3 days after surgery and(8.4±1.7)° at final follow-up. VAS, ODI, anterior height of injured vertebral body, and sagittal Cobb angle of affected segment were significantly improved at 3 days after operation and at final follow-up (P<0.05). Two patients had complications, including asymptomaticcement leakage in 1 patient and superficial wound infection in 1 patient. CONCLUSION: Posterior short-segment pedicle screw internal fixation combined with vertebroplasty for the treatment of Kümmell disease with kyphosis has relatively small surgical trauma, excellent clinical results, good vertebral height recovery, satisfactory correction of kyphotic angle, and fewer complications, etc. It is a safe and effective surgical method to treat Kümmell disease with kyphosis.

Endplate injury as a risk factor for cage retropulsion following transforaminal lumbar interbody fusion: An analysis of 1052 cases.

ABSTRACT: Although transforaminal lumbar interbody fusion (TLIF) is a widely accepted procedure, major complications such as cage retropulsion (CR) can cause poor clinical outcomes. Endplate injury (EI) was recently identified as a risk factor for CR, present in most levels developing CR. However, most EIs occurred in non-CR levels, and the features of EIs in CR levels remain unknown.The aim of this study was to identify risk factors for CR following TLIF; in particular, to investigate the relationship between EIs and CR, and to explore the features of EIs in CR.Between October 2010 and December 2016, 1052 patients with various degenerative lumbar spinal diseases underwent bilateral instrumented TLIF. Their medical records, radiological factors, and surgical factors were reviewed and factors affecting the incidence of CR were analyzed.Twenty-one patients developed CR. Nine had back pain or leg pain, of which six required revision surgery. A pear-shaped disc, posterior cage positioning and EI were significantly correlated with CR (P < .001, P = .001, and P < .001, respectively). Computed tomography (CT) scans revealed the characteristics of EIs in levels with and without CR. The majority of CR levels with EIs exhibited apparent compression damage in the posterior part of cranial endplate on the decompressed side (17/18), accompanied by caudal EIs isolated in the central portion. However, in the control group, the cranial EIs involving the posterior part was only found in four of the total 148 levels (P < .001). Most of the injuries were confined to the central portion of the cranial or caudal endplate or both endplates (35 in 148 levels, 23.6%). Additionally, beyond cage breaching into the cortical endplate on lateral radiographs, a characteristic appearance of coronal cage misalignment was found on AP radiographs in CR levels with EIs.A pear-shaped disc, posterior cage positioning and EI were identified as risk factors for CR. EI involving the posterior epiphyseal rim had influence on the development of CR. Targeted protection of the posterior margin of adjacent endplates, careful evaluation of intraoperative radiographs, and timely remedial measures may help to reduce the risks of CR.

Anteroinferior Psoas Technique for Oblique Lateral Lumbar Interbody Fusion: Technical Note and Case Series.

OBJECTIVE: The aim of the present paper was to evaluate cases of lumbar degenerative diseases treated with oblique lateral interbody fusion (OLIF) using a modified lateral approach (i.e. anteroinferior psoas exposure under direct vision) and to analyze the effect and safety of this approach. METHODS: From June 2016 to April 2019, a total of 226 patients with an average age of 65.5 ± 16.2 years (98 men and 128 women) with degenerative lumbar diseases who underwent the AIP approach of OLIF were followed up and analyzed retrospectively. Data concerning operative and clinical parameters were collected, including operative time, intraoperative estimated blood loss, duration of postoperative hospital stay, and time to ambulation after surgery. For the assessment of clinical outcomes, the visual analogue scale (VAS) score (for back pain) and the Oswestry disability index (ODI) were calculated. Complications were also recorded as surgical exposure approach-related complications. More than 6 months after surgery, 132 patients consented to having MRI examinations to evaluate the psoas muscle atrophy when they were followed up. RESULTS: The mean operative time was 82.5 ± 31.6 min. The mean operative time for each segment of OLIF was 43.3 ± 15.5 min. The mean blood loss was 48.0 ± 11.6 mL. The mean blood loss for each segment of OLIF was 25.3 ± 10.1 mL. No patients needed blood transfusion intraoperatively or postoperatively. The mean hospital stay was 4.1 ± 2.1 days. All patients were followed up for 12-31 months (mean 18.2 months). Clinical assessment showed that the VAS and ODI scores at 6 months after surgery were markedly lower than the preoperative scores (P < 0.001) but did not differ from the scores at the final follow-up (P > 0.05). There was no significant difference in percentage changes of the cross-sectional area of the lean psoas muscle and the T2 signal intensity ratio of gross psoas to quadratus lumborum muscles between the left side (operative side) and the right side (nonoperative side) (P > 0.05). A total of 11 surgical exposure approach-related complications were reported, with an incidence of 4.9%: transient thigh pain/numbness, psoas weakness (2.2%), sympathetic chain injury (1.3%), cage subsidence (0.9%), and segmental artery injury (0.4%). There was no permanent motor neurological deficit, and no injury of vascular, ureter or peritoneal membranes. CONCLUSION: The anteroinferior psoas approach for OLIF is safe and can preserve the psoas and lumbar plexus.

Symptomatic Postoperative Discal Pseudocyst After Percutaneous Endoscopic Interlaminar Discectomy: Case Report and Literature Review.

BACKGROUND: A postoperative discal pseudocyst (PDP) is a cystic lesion that is formed in the operation area of the intervertebral disc, leading to recurrence or even worse symptoms. To our knowledge, to date, there is no research focusing specifically on PDP following percutaneous endoscopic interlaminar discectomy (PEID). CASE PRESENTATION: We present the case of a 27-year-old man with L5 S1 intervertebral disc herniation who was treated with PEID after failed conservative treatment. His leg pain was relieved immediately but reoccurred on the 40th day. MRI showed a PDP. Because loxoprofen and bedrest were ineffective and the patient was anxious, we performed a cystectomy. The patient's symptoms were significantly relieved, and a 6-month follow up showed no recurrence both clinically and on MRI. CONCLUSION: A PDP is more likely to form using the interlaminar approach than the transforaminal approach. For patients with mental stress, severe pain, and neurological symptoms, surgery is suggested to remove the cyst. Discectomy cannot be performed when disc degeneration is mild.

Nontraumatic acute paraplegia associated with cervical disk herniation.

BACKGROUND: Acute paraplegia is a true emergency. It is often the result of trauma but is rarely reported in association with cervical disk herniation in patients without antecedent injury. METHODS: Case report. FINDINGS: This 75-year-old man presented with acute paraplegia due to severe compression of the spinal cord by herniation of the C4-C5 cervical disk. He underwent emergency diskectomy and anterior fusion. Postoperatively, his neurologic functions improved gradually. CONCLUSIONS: Cervical disk herniation should be considered in the differential diagnosis of nontraumatic acute paraplegia. Pre-existing narrowed canal is an important predisposing factor and excessive neck movements are believed to be triggering factors. Immediate early decompressive surgery is recommended to avoid irreversible progression of neurologic deficit.

[Establishment of a novel mouse mode of elastase-induced chronic obstructive pulmonary disease related osteoporosis].

OBJECTIVE: To establish and evaluate the model of chronic obstructive pulmonary disease (COPD) with osteoporosis induced by elastase in mice. METHODS: Twenty four healthy female 8-week-old C57BL / 6 mice (weighing about 18 g) were randomly divided into three groups. The control group was given intratracheal drip of normal saline, the experimental group 1 and the experimental group 2 were given intratracheal drip of elastase, the control group and the experimental group 1 were kept for 8 weeks and then killed, the experimental group 2 was kept for 12 weeks and then killed. HE staining was used to evaluate the histopathological changes of lung and tibia in the control and experimental groups. The levels of serum inflammatory factors and broncho alveolar lavage factors (BALF) were detected by ELISA. Micro CT was used to detect the bone mass related parameters of mouse femur. The expression of osteoclastic and osteogenic genes was detected by real-time fluorescence quantitative PCR. RESULTS: Lung histopathology showed that the structure of alveoli in the experimental group was disordered, the walls of alveoli became thin or broken, and the alveoli cavity expanded. IL-6 and TNF-α in BALF were significantly higher than those in control group (P<0.001), while IL-1ß and TNF-α in serum inflammatory factors were significantly higher than those in control group (P<0.001). BV / TV(bone volume fraction), TB.Th(average bone trabecular thickness) and TB.N(average bone trabecular number) in the experimental group were significantly lower than those in the control group (P<0.05), TB.Sp (average bone trabecular separation) and BS / BV (bone surface area fraction) in the experimental group were significantly higher than those in the control group (P<0.01). Compared with the control group, the expression of osteoclast related marker genes increased in the experimental group (P<0.05), but decreased in the experimental group(P<0.05). The results of experiment 1 and experiment 2 were time-dependent. CONCLUSION: In this study, elastase was used to construct a COPD model with osteoporosis successfully, which provides a suitable animal model for the future study of the pathogenesis of COPD with osteoporosis.