Intervertebral Fusion with Mobile Microendoscopic Discectomy for Lumbar Degenerative Disc Disease

Supplementary decompression and extended surgical time contribute to hidden blood loss In percutaneous endoscopic lumbar discectomy

Background

It is widely believed that the Percutaneous endoscopic lumbar discectomy (PELD) is associated with minimal blood loss. However, significant perioperative hidden blood loss (HBL) is frequently unaccounted for. This study aimed to investigate HBL and peri-operative factors contributing to HBL in a series of individuals undergoing PELD.

Method

ology: A total of 156 consecutive patients with a mean age of 43.6 years (ranging from 18 to 80 years) who underwent PELD at our department from May 2019 to November 2020, were included in the study. Factors including gender, age, body mass index, symptom duration, operation approach/technique, operation duration, the presence of associated chronic diseases, and improvements in the Visual Analog Scale (VAS) score, Japanese Orthopaedic Association (JOA) score and the Oswestry Disability Index (ODI) were analyzed, and Gross's formula was applied to calculate blood loss, which was used to determine HBL.

Results

The average total blood loss (TBL) was 221.0 ± 126.2 mL, while the average HBL was 181.7 ± 119.0 mL (82.2 % of TBL). There was no statistically significant difference in HBL between the transverse surgical approach and the interlayer approach. Additionally, no significant differences were observed in improvements in VAS, JOA, and ODI scores between the two surgical approaches. However, the multivariate linear regression analysis revealed that longer surgical time and foraminal decompression were factors contributing to the increase in HBL, which subsequently led to the occurrence of post-operative anemia.

Conclusion

HBL is significant in PELD cases with long surgical time and lumbar foraminal decompression.

"In-situ" formation of elastin-like recombinamer hydrogels with tunable viscoelasticity through efficient one-pot process

Despite the remarkable progress in the generation of recombinant elastin-like (ELR) hydrogels, further improvements are still required to enhance and control their viscoelasticity, as well as limit the use of expensive chemical reagents, time-consuming processes and several purification steps. To alleviate this issue, the reactivity of carboxylic groups from glutamic (E) acid distributed along the hydrophilic block of an amphiphilic ELR (coded as E50I60) with amine groups has been studied through a one-pot amidation reaction in aqueous solutions, for the first time. By means of this approach, immediate conjugation of E50I60 with molecules containing amine groups has been performed with a high yield, as demonstrated by the 1H NMR and MALDI-TOF spectroscopies. This has resulted in the preparation of viscoelastic irreversible hydrogels through the "in-situ" cross-linking of E50I60 with another ELR (coded as VKV24) containing amine groups from lysines (K). The rheology analysis demonstrated that the gelation process takes place following a dual mechanism dependent on the ELR concentration: physical cross-linking of I60 block through the hydrophobic interactions, and covalent cross-linking of E50I60 with VKV24 through the amidation reaction. While the chemical network formed between the hydrophilic E50 block and VKV24 ELR preserves the elasticity of ELR hydrogels, the self-assembly of the I60 block through the hydrophobic interactions provides a tunable physical network. The presented investigation serves as a basis for generating ELR hydrogels with tunable viscoelastic properties promising for tissue regeneration, through an ''in-situ", rapid, scalable, economically and feasible one-pot method.

Percutaneous transforaminal endoscopic decompression for the treatment of intraspinal tophaceous gout: A case report

RATIONALE

Intraspinal tophaceous gout is relatively rare condition presenting with major clinical manifestations, such as spinal cord or nerve roots compressions (radiculopathy). It is usually difficult to differentiate intraspinal tophaceous gout, lumbar disc herniation, stenosis of spinal canal, ossification of ligamentum flavum, and other degenerative spinal disorders from each other.

PATIENT CONCERNS

A 64-year-old man was admitted with a history of progressive low back pain for 11 months. He also presented with radiculopathy and numbness of his left lower extremity.

DIAGNOSES

Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) showed L4/5 disc herniation and lateral recess stenosis on the left side. During the operation of percutaneous transforaminal endoscopic decompression, intraspinal chalky white material was seen. Post-operative pathologic results confirmed the diagnosis of gouty tophi.

INTERVENTIONS

Percutaneous transforaminal endoscopic decompression was performed as treatment. Intraspinal chalky white material was seen. We removed most of the chalky white material and extruded nucleus.

OUTCOMES

His symptom subsided rapidly and no deterioration was noted 1 year post-operatively.

LESSONS

Although intraspinal tophaceous gout is not commonly seen, clinicians should take it into consideration as a possible differential diagnosis when the patient exhibits axial pain or neurological deficits with risk factors of gout. We identified and treated this case with percutaneous transforaminal endoscopic decompression for the first time and got an excellent outcome. Percutaneous transforaminal endoscopic surgery proved to be an effective and minimally invasive alternative for identifying and treating intraspinal tophaceous gout.

Revision Surgery after Percutaneous Endoscopic Transforaminal Discectomy Compared with Primary Open Surgery for Symptomatic Lumbar Degenerative Disease

Objective

To evaluate the clinical outcome of reoperation after percutaneous endoscopic lumbar discectomy (PELD) as compared with primary spinal decompression and fusion.

Methods

A retrospective study from December 2014 to December 2017 was conducted at Peking Union Medical College Hospital and comprised 39 patients with symptomatic lumbar degenerative disease (LDD): 13 post‐PELD who underwent reoperation (revision surgery group) and 26 who received primary spinal decompression and fusion (primary open surgery group). The two groups were compared regarding: operative time, blood loss, transfusion, hospitalization, postoperative visual analog scale (VAS) scores, Oswestry Disability Index (ODI) scores, Japanese Orthopedic Association (JOA) improvement rate, and postoperative complications. The Mann–Whitney U‐test was applied to analyze continuous parameters, and the χ²‐test for categorical parameters. Fisher's exact test was used for small data subsets.

Results

There was no statistically significant difference between the two groups in mean age (52.7 years vs 52.9 years), gender ratio (6 men‐to‐7 women vs 12 men‐to‐14 women), body mass index, medical history, preoperative diagnosis, or surgical spine level (P > 0.05). The mean operative time of the revision surgery group was significantly longer than that of the primary open surgery group (160.0 min vs 130.2 min, P < 0.05). The revision surgery group also had a significantly higher mean estimated blood loss, postoperative drainage, and length of hospital stay (P < 0.05). However, no significant differences were found between the two groups in terms of hemoglobin and hematocrit values, preoperatively and postoperatively. The rate of transitional neurological irritation was higher in the revision surgery group (61.5% vs 3.8%; P < 0.05), as was intraoperative durotomy and cerebrospinal fluid leakage (30.8% vs 3.8%, P < 0.05). At 1 month, the VAS and ODI scores of the primary open surgery group were significantly better than those of the revision surgery group, while the improvement in JOA scores was similar. After 6 and 12 months’ follow‐up, the VAS and ODI scores and the rates of JOA improvement were comparable.

Conclusion

Patients with LDD who received primary spinal decompression and fusion experienced lower rates of perioperative complications and shorter hospitalization compared with patients who underwent revision surgery after PELD, but the clinical outcomes at the last follow‐up of both groups were satisfactory.