Continuous neural control of a bionic limb restores biomimetic gait after amputation.

For centuries scientists and technologists have sought artificial leg replacements that fully capture the versatility of their intact biological counterparts. However, biological gait requires coordinated volitional and reflexive motor control by complex afferent and efferent neural interplay, making its neuroprosthetic emulation challenging after limb amputation. Here we hypothesize that continuous neural control of a bionic limb can restore biomimetic gait after below-knee amputation when residual muscle afferents are augmented. To test this hypothesis, we present a neuroprosthetic interface consisting of surgically connected, agonist-antagonist muscles including muscle-sensing electrodes. In a cohort of seven leg amputees, the interface is shown to augment residual muscle afferents by 18% of biologically intact values. Compared with a matched amputee cohort without the afferent augmentation, the maximum neuroprosthetic walking speed is increased by 41%, enabling equivalent peak speeds to persons without leg amputation. Further, this level of afferent augmentation enables biomimetic adaptation to various walking speeds and real-world environments, including slopes, stairs and obstructed pathways. Our results suggest that even a small augmentation of residual muscle afferents restores biomimetic gait under continuous neuromodulation in individuals with leg amputation.

A Pearl for Pretibial and Forearm Repair Following Mohs Micrographic Surgery.

Wound repair of the pretibial and forearm regions presents a challenge during dermatologic surgery as these areas are under significant tension and exhibit increased skin fragility. Various methodologies have been proposed for the closure and repair of such wounds, however, the use of the bilayered suture technique may be simpler and more effective than other techniques such as the pinch stitch, pully stitch, slip-knot stitch, pulley set-back dermal suture, horizontal mattress suture, pully stitch, and tandem pulley stitch. Our objective was to describe a novel method for the repair of pretibial and forearm wounds following Mohs micrographic surgery utilizing bilayered closure followed by tissue adhesive application.  J Drugs Dermatol. 2024;23(5):380.     doi:10.36849/JDD.7139  .

[Ischemia-related compartment syndromes in vascular surgery]. / Ischämisch bedingte Kompartmentsyndrome in der Gefäßchirurgie.

Even after the endovascular revolution, acute compartment syndrome (CS) remains an important and frequently present differential diagnosis after many operations. Based on a qualitative review this article gives an overview of the most frequent forms of CS as well as some less frequent entities that require attention in the routine clinical practice. Additionally, the pathophysiology, diagnostics and treatment as well as current research topics for CS, especially concerning the lower leg, are dealt with in detail. In summary, nothing has essentially changed ever since the first description of CS in that the clinical estimation remains the gold standard. The detection and the adequate treatment especially of abdominal CS and CS of the lower leg remain a key competence of vascular surgeons.

Endovascular repair of an abdominal aortic aneurysm with external iliac artery occlusion using VBX as the contralateral leg via axillary delivery: A case report.

RATIONALE: A hostile iliac access route is an important consideration when enforcing endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA). Herein, we report a case of AAA with unilateral external iliac artery occlusion, for which bifurcated EVAR was successfully performed using a single femoral and brachial artery access. PATIENT CONCERNS: A 76-year-old man who had undergone surgery for lung cancer 4.5 years prior was diagnosed AAA by computed tomography (CT). DIAGNOSIS: Two and a half years before presentation, CT revealed an infrarenal 48 mm AAA, which had enlarged to 57 mm by 2 months preoperatively. CT identified occlusion from the right external iliac artery to the right common femoral artery, with no observed ischemic symptoms in his right leg. The right external iliac artery, occluded and atrophied, had a 1 to 2 mm diameter. INTERVENTION: Surgery was commenced with the selection of a Zenith endovascular graft (Cook Medical) with an extended body length. Two Gore Viabahn VBX balloon expandable endoprosthesis (VBX; W.L. Gore & Associate) were delivered from the right axilla as the contralateral leg. OUTCOMES: CT scan on the 2nd day after surgery revealed no endoleaks. LESSONS: While the long-term results remain uncertain, this method may serve as an option for EVAR in patients with unilateral external iliac artery occlusion.

[Molecular mechanism of residual lumbago and leg pain after transforaminal endoscopic treatment of lumbar disc herniation].

OBJECTIVE: To observe the residual of lumbago and leg pain with contained type （CT） and non-contained type （NCT） lumbar disc herniation （LDH） after transforaminal endoscopic treatment, and to explore the role of hypoxia-inducible factor-1α（HIF-1α） and transient receptor potential vanillate 1（TRPV1） pathway. METHODS: A total of 68 single-segment LDH patients were selected from July 2021 to October 2022, including 44 males and 24 females；aged 26 to 67 years old with an average of（43.63±11.94） years old；course of disease was 4 to 36 （18.91±10.34） months；body mass index was （24.45±4.00） kg·m-2；there were 7 cases of L3,4 segments, 32 cases of L4,5 segments, and 29 cases of L5S1 segments. All of them were performed with percutaneous intervertebral endoscopic extraction of nucleus pulposus and were divided into contained group（CT group） and non-contained group （NCT group） with 34 cases respectively according to the integrity of outer layer of fibrous annulus observed during operation. A total of 17 patients who underwent open surgery for scoliosis or vertebral fracture were selected as control group, including 12 males and 5 females；aged 21 to 65 years old with an average of （39.41±12.80） years old；body mass index was （24.86±4.11） kg·m-2. The relative mRNA expression quantity of HIF-1α, TRPV1 in nucleus pulposus were measured by quantitative real-time PCR. The contents of neurokinin 1 receptor （NK1R）, nerve growth factor （NGF）, vascular endothelial growth factor （VEGF） in nucleus pulposus and the serum substance P （SP） and calcitonin gene-related peptide （CGRP） were detected by enzyme linked immunosorbent assay （ELISA）. The threshold of lumbar tenderness was detected by a pressure pain meter. The degree of lumbago and lumbar function were evaluated by visual analog scale （VAS） and Oswestry disability index （ODI） separately. The residual rate of postoperative lumbago and leg pain was assessed. RESULTS: The mRNA relative expression quantity of HIF-1α and TRPV1, and the contents of NK1R, NGF and VEGF in nucleus pulposus, and the levels of serum SP and CGRP before surgery in the NCT group were higher than those in the CT group（P<0.05）, and those in the CT group were higher than the control group（P<0.05）. At day 7 after surgery, the serum SP and CGRP levels, lumbago and leg pain VAS scores and lumbar ODI index in two LDH groups were lower than before surgery （P<0.05）, and those in the NCT group were higher than the CT group（P<0.05）, and the threshold of lumbar tenderness in the NCT group was lower than the CT group（P<0.05）. The differences of lumbago and leg pain VAS scores, lumbar ODI index and lumbar tenderness threshold between preoperative and postoperative 7 days in the NCT group were lower than those in the CT group（P<0.05）. The residual rate of lumbago and leg pain at 7 days after surgery in the NCT group was higher than that in the CT group（P<0.05）. CONCLUSION: HIF-1α and TRPV1 pathway promoted the excessive production of NGF, VEGF, NK1R in nucleus pulposus and serum neuropeptides SP and CGRP, which may lead to the higher residual rate of lumbago and leg pain with non-contained lumbar disc herniation postoperative.

An innovative staged prosthetic lengthening reconstruction strategy for osteosarcoma-related leg discrepancy.

Correction of leg length discrepancy (LLD) in skeletally mature patients with osteosarcoma was rarely reported and quite challenging. This study aimed to propose a treatment strategy of staged lengthening and reconstruction with a standard static prosthesis to address LLD and restore limb function. It also evaluated the effectiveness of the strategy in terms of leg lengthening, functional outcomes, and complications. The strategy for lengthening included three stages. In stage 1, the previous prosthesis was removed and an external fixator with a temporary rod-cement spacer was placed. In this stage, the external fixator was used to lengthen the limb to the appropriate length. In stage 2, the external fixator was removed and the old rod-cement spacer was replaced with a new one. In stage 3, the rod-cement spacer was removed and the standard static prosthesis was planted. Nine skeletally mature distal femoral osteosarcoma patients with unacceptable LLD were treated in our institution from 2019 to 2021. We performed a chart review on nine patients for the clinical and radiographic assessment of functional outcomes, LLD, and complications. The mean (range) leg lengthening was 7.3 cm (3.6-15.6). The mean (range) LLD of the lower limbs decreased from 7.6 cm (4.1-14.2) before the lengthening to 0.3 cm (- 0.3 to 2.1) at the final follow-up with statistical significance (P = 0.000). The mean (range) Musculoskeletal Tumor Society score improved from 30.3% (16.7%-53.3%) before the lengthening to 96.3% (86.7%-100%) at the final follow-up with statistical significance (P = 0.000). Three patients (33.3%) had a minor complication; none needed additional surgical intervention. In the short term, the current staged lengthening and reconstruction with standard static prosthesis provided satisfactory functional outcomes and LLD correction with few complications. The long-term effects of this method need further exploration.

Mechanical energy flow analysis in athletes with and without anterior cruciate ligament reconstruction during single-leg drop landing.

Techniques that reduce mechanical energy have been linked to lower chances of experiencing an Anterior Cruciate Ligament (ACL) injury. Although there is evidence that movement patterns are altered in athletes who have undergone Anterior Cruciate Ligament Reconstruction (ACLR), energy transfer mechanisms have not been examined. This study aimed to compare energy flow mechanisms during single-leg drop landing between athletes with and without history of ACLR. A total of 20 female athletes were included in this study. Ten participants underwent ACLR 12 months ago (mean age, 21.57 ± 0.41 years) and 10 were healthy controls (mean age, 20.89 ± 0.21 years). Participants executed the single-leg drop landing (SLL) maneuver by descending from a 30 cm wooden box and landing on the tested leg on an embedded force plate. Information collected during the SLL trials was refined using rigid-body analysis and inverse dynamics within Nexus software, ultimately allowing construction of skeletal models of the athletes. Ankle and knee mechanical energy expenditure (MEE) was higher in the control participants during landing. However, the result for the hip MEE demonstrated that MEE of the control group was significantly lower compared with the ACLR group, but MEE of the control subjects was higher as compared to ACLR group (p ˂ 0.05). Results suggest the avoidant use of the quadriceps muscle post ACLR leads to knee-avoidant mechanics and loss of knee joint power generation during a SLL task.

A large preoperative pelvic oblique angle affects perception of leg length discrepancy after total hip arthroplasty.

BACKGROUND: In some cases, patients feel a perceived leg length discrepancy (P-LLD) despite no radiographic leg length discrepancy (R-LLD) after total hip arthroplasty (THA). We aimed to investigate the rate of postoperative P-LLD and the factors that cause postoperative P-LLD. METHODS: A retrospective study was conducted on 100 patients with R-LLD ≤5 mm after THA. Patients were classified into two groups based on P-LLD post-THA: group P (with P-LLD) and group E (without P-LLD). Relevant data on the general characteristics and radiological findings between the two groups were compared. RESULTS: We observed that 25 & 75% of patients belonged to group P and group E, respectively, with no significant difference in patient background. Postoperative Japanese Orthopedic Association (JOA) classification of pain and activities of daily living scores were significantly lower in group P than in group E (37.2 ± 3.9 vs. 39.1 ± 2.2, respectively; P = 0.013, and 16.2 ± 4.2 vs. 18.2 ± 2.2, respectively; P = 0.011). The preoperative pelvic oblique angle (POA) was significantly larger in group P than in group E (3.3 ± 2.3° vs. -0.2 ± 2.1°; respectively; P < 0.01). The pelvis tilted toward the surgical side was significantly higher in group P than in group E(88% vs 57%; respectively; P = 0.013). The preoperative C7 coronal vertical axis (C7 CVA) was significantly larger in group P than in group E (6.7 ± 14.7 mm vs. -0.2 ± 10.3 mm; respectively; P = 0.028). Multivariate logistic analysis revealed that preoperative POA (OR, 3.71; 95% CI: 1.86-8.12; P < 0.01) and the pelvis tilted toward the surgical side (OR, 4.14; 95% CI: 2.07-9.71; P = 0.022) were independent risk factors for P-LLD after THA. CONCLUSION: Even though there was no postoperative R-LLD, 25% of patients had P-LLD. A large preoperative POA and the pelvis tilted toward the surgical side were independent risk factors for P-LLD after THA.

Paresthesia Is Predictive of Symptom Recurrence After Fasciotomy for Exertional Compartment Syndrome of the Leg.

BACKGROUND: Exertional compartment syndrome (ECS) is an underdiagnosed cause of lower extremity pain among athletes. The condition can be managed operatively by fasciotomy to relieve excess compartment pressure. However, symptom recurrence rates after fasciotomy are considerable, ranging from 3% to 17%. HYPOTHESIS: Leg paresthesia and its distribution during ECS episodes would be a significant predictor of outcomes after fasciotomy. STUDY DESIGN: Retrospective cohort study. LEVEL OF EVIDENCE: Level 4. METHODS: We conducted a retrospective chart review of patients who underwent fasciotomy for ECS at our center from 2010 to 2020 (institutional review board no. 21-00107). We measured postoperative outcomes including pain frequency and severity, Tegner activity level, and return to sport. Significant predictors of outcomes were identified using multivariable linear and logistic regression. P values <0.05 were considered significant. RESULTS: A total of 78 legs (from 42 male and 36 female participants) were included in the study with average follow-up of 52 months (range, 3-126 months); 33 participants (42.3%) presented with paresthesia. Paresthesia was an independent predictor of worse outcomes, including more severe pain at rest (P = 0.05) and with daily activity (P = 0.04), reduced postoperative improvement in Tegner scores (P = 0.04), and lower odds of return to sport (P = 0.05). Those with paresthesia symptoms in the tibial nerve distribution had worse outcomes than those without paresthesia in terms of preoperative-to-present improvement in pain frequency (P < 0.01), pain severity at rest (P < 0.01) and with daily activity (P = 0.04), and return to sport (P = 0.04). CONCLUSION: ECS patients who present with paresthesia have worse pain and activity outcomes after first-time fasciotomy, but prognosis is worst among those with tibial nerve paresthesia. CLINICAL RELEVANCE: Paresthesia among ECS patients is broadly predictive of more severe recurrent leg pain, reduced activity level, and decreased odds of return to sport after fasciotomy.

Alteration of the calf strength by heel cord lengthening, gastrocnemius recession through tenotomy or fasciotomy. A retrospective clinical force analysis before and after surgery.

BACKGROUND: Indications for surgical corrections about the Achilles tendon are increasing as additional measures in reconstructive interventions about the foot. These indications include shortened gastrocnemii, which cause a so-called 'functional pes equinus' and secondary forefoot imbalances, as well as corrections of pes planus and cavus. Surgery about the heel cord may also be indicated for achillodynia and diabetic pressure ulcers. However, there is a lack of evidence that quantifies the results of lengthening procedures about the heel cord. The aim of this study was to quantify the exact changes in calf strength one year after elongating the triceps surae, by measuring flexion forces in 90 degrees knee flexion and knee extension. METHODS: This study involves 69 patients who were examined for calf strength preoperatively and 1 year after gastrocnemius release. A new device, the Leonardo Mechanograph® (Novotec Medical) was used to measure calf strength. Measurements were performed with the knee flexed and extended. RESULTS: The operated leg had an overall statistically significant reduction in strength after surgery. Changes were similar on the contralateral leg. The difference in force reduction between the operated and non-operated leg was not statistically significant CONCLUSION: A correlation between measured plantar flexion forces of the foot after a reconstructive foot operation with or without a lengthening procedure about the calf musculature could not be established. LEVEL OF EVIDENCE: Level III: retrospective cohort study.

A Nasal Columellar Base Stabilizing Suture Technique.

SUMMARY: To achieve a more aesthetic and narrower columella, most of the required changes concern the middle and base of the columella. Narrowing and reshaping the columellar base require a sequential approach with good anatomical knowledge and aesthetics analysis. The columellar base is a three-dimensional structure that must be analyzed following three axes: transverse (thickness or width), frontal (height), and sagittal (nasolabial angle). Sutures that aim to close the distance between the medial crura footplates frequently result in modifying the nasolabial angle because of caudal protrusion of the columellar soft tissue. Methods to keep an adequate nasolabial angle are needed. A transverse columellar base stabilizing suture acting on these three axes, which enables maintenance of results after columellar base management, is described in this article.

[The value of the medial plantar flap in the repair of loss of soft tissue in the distal quarter of the leg]. / Intérêt du lambeau plantaire médial dans la réparation des pertes de substance du quart distal de la jambe.

OBJECTIVE: Soft tissue repair of the distal leg is a challenge for the surgeon. The objective of our work is to evaluate the interest of medial plantar flaps in the repair of soft tissue loss in the distal quarter of the leg, by highlighting the advantages and disadvantages of this technique. METHODS: We conducted a retrospective study over 4 years in the Department of Plastic, Reconstructive and Burn Surgery of the Mohammed V Military Teaching Hospital of Rabat, including 8 patients admitted for coverage of a distal quarter of the leg with a medial plantar flap. RESULTS: Eight patients were included, 5 men and 3 women with an average age of 45.5 years. All patients received coverage with a medial plantar flap. The functional and aesthetic results were very good with a low complication rate. CONCLUSION: The medial plantar flap should no longer be reserved for covering loss of substance of the foot only, but should be integrated into the therapeutic arsenal of reconstruction of the distal quarter of the leg.

Magnitude of Change in Leg Length and Clinical Impact Following Medial Unicompartmental Knee Arthroplasty.

BACKGROUND: Change in leg length and leg-length discrepancy (LLD) are common concerns among patients undergoing medial unicompartmental knee arthroplasty (UKA). This study aimed to quantify the magnitude of leg-length change, prevalence of postoperative LLD, and their clinical implications following medial UKA. METHODS: Leg length and mechanical hip-knee-ankle angle (mHKA) were retrospectively measured in 332 patients following unilateral robotic-arm assisted medial UKA for medial compartment osteoarthritis, using calibrated long-leg radiographs. The Knee Injury and Osteoarthritis Otcome Score for Joint Replacement and patient satisfaction were analyzed to assess impact of leg-length change and LLD on outcomes. RESULTS: Following medial UKA, median leg-length change was 2.0 mm (interquartile range, -1.0 to 5.0 mm; P < .001) with a mean correction in mHKA of 4.4° ± 2.7 (P < .001). A total of 158 patients (48%) had a leg-length increase by 0 to 5 mm, 64 (19%) by 6 to 10 mm, and 11 (3%) by >10 mm. Leg-length change was positively correlated with mHKA correction (R = 0.44, P < .001). Postoperatively, moderate (5 to 10 mm) and substantial LLD (≥10 mm) were present in 49% and 17% of patients, respectively. Four-year Knee Injury and Osteoarthritis Outcome Score for Joint Replacement were comparable between patients with and without substantial postoperative LLD (P = .976). Proportions of satisfied patients were similar between groups (P = .687). CONCLUSION: Following medial UKA, the majority of patients had a moderate increase in leg length, the magnitude of which was positively correlated to the correction in mechanical alignment. Postoperative substantial LLD was not uncommon (17% prevalence); however, it had no significant impact on patient-reported outcomes or satisfaction at 4 years follow-up.

Intraoperative Ultrasound for Extracting Deep-Seated Radio-Opaque Foreign Body from Calf: A Case Report.

CASE: A 50-year-old man presented with chronic refractory symptoms of radiating leg pain with muscle cramps because of a retained bullet in the calf after being shot in 1990. Radiographs confirmed the bullet lodged in posterolateral aspect of calf abutting proximal fibula. An intraoperative point-of-care ultrasound aided in accurate localization of bullet, thereby facilitating precise planning of surgical incision and subsequent removal. CONCLUSIONS: Ultrasound can be used as an alternative tool for safe surgical extraction of deep-seated metallic object with minimal tissue dissection, obviating the need for C-arm.

[Anatomical study of the architecture of the cutaneous branch-chained blood vessels in the medial lower leg in adult].

Objective: To investigate the architecture of the cutaneous branch-chained blood vessels in the medial lower leg and provide the anatomical basis for design and clinical application of the cutaneous branch-chained flap from this region. Methods: The experimental research method was used. From March to May 2023, the anatomical study was conducted on the 5 voluntarily donated fresh adult (aged 50 to 70 years, all male) cadaveric specimens from Hangzhou Normal University School of Basic Medical Sciences. The fine anatomy under microscope was performed on each lower leg specimens of 5 corpses (1 lower leg specimen was conducted with digital radiography (DR) scan before fine anatomy), to observe, measure, and record the course of posterior tibial artery, quantity of perforator, the distance between the perforating point of each perforator and the medial condyle of tibia, the external diameter of posterior tibial artery perforator, the length of perforator pedicle, the horizontal distance between the posterior tibial artery perforator and the saphenous nerve, and the course of each perforator within superficial fascia after crossing the deep fascia and the distribution of the cutaneous branch-chains. The DR scan under the perfusion of barium sulfate was conducted in one lower leg specimen to observe the distribution of cutaneous branch-chained vascular network (hereinafter referred to as vascular chain) between perforators. Transparent skin specimen was made from one leg specimen after anatomy to observe the distribution of perforators and vascular chains between perforators. Results: In 5 lower leg specimens, the upper part of posterior tibial artery was located deep in soleus muscle, and the lower part was located between the medial edge of gastrocnemius muscle and flexor digitorum longus muscle. A total of 28 posterior tibial artery perforators were identified, with an average of 5.6 branches in each lower leg. The distance between the perforating point of perforator and the medial condyle of tibia ranged from 6.5 to 36.0 cm, mainly distributed at 22.0 (15.1, 28.1) cm from the medial condyle of tibia, in zones 3 to 6. The external diameters of perforators of posterior tibial arteries were 0.7-1.1 mm. The length of perforator pedicle was 1.0-4.5 cm, and the horizontal distance between the posterior tibial artery perforator and the saphenous nerve was 0.5-3.0 cm. The fine anatomy under microscope showed that the posterior tibial artery perforators had long upward and downward branches after crossing the deep fascia, and the ascending branches and descending branches were anastomosed longitudinally to form the nutrient cutaneous branch-chain in the medial lower leg. DR scan and transparent skin specimen both showed that longitudinal vascular chain was formed between the posterior tibial artery perforators, the transparent skin specimen also showed that longitudinal blood vessel chains included the direct connecting vessels in the adipose layer and the indirect connecting vessels in the subdermal layer. Conclusions: The cutaneous branch-chained vessels in the medial lower leg are constructed by posterior tibial artery perforators, direct connecting vessels, indirect connecting vessels, and traffic branches. The cutaneous branch-chained flap is reliable in terms of vascular anatomy, and can carry the saphenous nerve for partial restoration of its sensation, thus it is an ideal flap.

[Effects of low position lateral supramalleolar flap carrying periosteum and proximal leg propeller flap in relay repair of electric burn wounds of forefoot].

Objective: To explore the effects of low position lateral supramalleolar flap carrying periosteum and proximal leg propeller flap in relay repair of electric burn wounds of forefoot. Methods: A retrospective observational study was conducted. From January 2019 to January 2022, 12 patients with electric burn wounds of forefoot meeting the inclusion criteria were admitted to the Sixth Hospital of Shanxi Medical University, including 10 males and 2 females, aged 23-65 years. After debridement, the wound with an area of 6.0 cm×3.0 cm to 15.0 cm×7.0 cm was repaired with the lateral supramalleolar flap carrying part of the periosteum of the distal tibia and fibula with the rotation point moved down to the front of the ankle joint. The area of the cutted flap was 6.5 cm×3.5 cm-15.5 cm×7.5 cm. At the same stage, the donor site wound of lateral supramalleolar flap was repaired with peroneal artery or superficial peroneal artery perforator propeller flap in relay, with the relay flap area of 3.0 cm×1.5 cm-15.0 cm×4.0 cm. After operation, the survival of the lateral supramalleolar flap and relay flap, and the wound healing of the relay flap donor site were observed. During follow-up, the shapes of the lateral supramalleolar flap and its donor site were observed. Results: After operation, one patient developed secondary blisters in the superficial skin distal to the lateral supramalleolar flap, which healed after dressing change, and the lateral supramalleolar flap and relay flaps survived well in the other patients; the donor site wound of the relay flap healed well. During follow-up of 12-18 months, the lateral supramalleolar flaps were in good shape and not bloated, with only linear scar left in the donor site of the flap. Conclusions: The low position lateral supramalleolar flap carrying periosteum can repair electric burn wounds of forefoot with advantages including reliable blood supply, low rotation point, and better repair effects. The use of relay flap to repair the donor site of lateral supramalleolar flap can reduce the damage to the appearance and function of the donor site.

Risk factor of residual leg numbness after lumbar microdiscectomy for lumbar disc herniation.

Although patients with lumbar disc herniation (LDH) can achieve significant relief from lower back and leg pain after lumbar microdiscectomy, a few patients complain of discomfort due to residual leg numbness (RLN). This study aimed to identify potential risk factors for RLN after lumbar microdiscectomy. We prospectively collected and analyzed patients with LDH who underwent microdiscectomy between September 2016 and December 2020. All included patients had preoperative LN symptoms. Patients with RLN were defined as those with LN at the last follow-up. The relationships between RLN and sex, age, body mass index (BMI), current smoking status, diabetes mellitus, revision surgery, preoperative LN Numeric Rating Scale (NRS) score, duration of preoperative LN, RLN at discharge, sagittal range of motion (SROM), Modic change, disc Pfirrmann grade were analyzed. The RLN was observed in 33.5% (112/334) of patients at the last follow-up. No significant differences were observed in age, sex, BMI, current smoking status, or diabetes between the RLN and non-RLN groups. The preoperative LN NRS score, preoperative LN duration, rate of RLN at discharge, and revision surgery were significantly higher in the RLN group than those in the non-RLN group. Multivariate logistic regression analysis identified the preoperative LN NRS score, duration of preoperative LN, RLN at discharge, revision surgery, and SROM as risk factors for RLN in the long-term follow-up. Patients with higher preoperative LN NRS scores and SROM, longer preoperative LN duration, RLN at discharge, and revision surgery were more likely to experience RNL after lumbar microdiscectomy.