Arthroscopic inferior leaf meniscectomy of the involved anterior horn in the lateral meniscus horizontal tear via an accessary extreme far anteromedial portal

BACKGROUND

An accessory extreme far anteromedial portal can improve visualisation and ease inferior leaf meniscectomy in patients with lateral meniscal anterior horn horizontal tears. However, the therapeutic outcomes of adding an accessory extreme far anteromedial portal remain unclear. This study aimed to evaluate the clinical efficacy of adding an accessory extreme far anteromedial portal for treating lateral meniscal horizontal tears involving the anterior horns.

METHODS

This retrospective study included 101 patients with anterior horn involvement in lateral meniscal horizontal tears who underwent arthroscopic unstable inferior leaf meniscectomy between January 2016 and December 2020. The pathologies were diagnosed using physical examinations and magnetic resonance imaging. The anterior horn involved in the lateral meniscal horizontal tears was treated using inferior leaf meniscectomy. The primary endpoints were changes in the visual analogue scale, Lysholm, International Knee Documentation Committee, and Tegner scores at the final follow-up. The secondary endpoint was meniscal cure rate at 3 months postoperatively. The preoperative and postoperative functional scores were compared. The occurrence of complications was recorded.

RESULTS

All patients were followed up for an average of 4.9 ± 1.2 years (range 2.3-7.5 years). After 4 months, none of the patients experienced pain, weakness, instability, or tenderness in the lateral joint line, achieving an imaging cure rate of 98%. At the final follow-up, significant postoperative improvements were observed in the average values of the visual analogue scale score (3.5 ± 0.7 vs. 0.7 ± 0.6), Lysholm score (62.7 ± 4.4 vs. 91.8 ± 3.1), International Knee Documentation Committee score (61.9 ± 3.7 vs. 91.7 ± 9.5), and Tegner score (2.0 ± 0.7 vs. 6.1 ± 0.7). Excellent Lysholm scores were obtained in 81 patients, and good outcomes were obtained in 18 patients, with an excellent-to-good rate of 98.0%.

CONCLUSIONS

Inferior leaf resection via the accessory far anteromedial portal is a safe treatment option for the involved anterior horn in lateral meniscal horizontal tears. This approach enhances visibility and facilitates surgical procedures, with minimal complications.

Myelitis with flaccid paralysis due to Japanese encephalitis: case report and review of the literature

Background

Japanese encephalitis is an arthropod-borne zoonotic flavivirus infection endemic to tropical and subtropical Asia. A minority of infections leads to a symptomatic course, but affected patients often develop life-threatening encephalitis with severe sequelae.

Literature review

Myelitis with flaccid paralysis is a rare complication of Japanese Encephalitis, which—according to our literature search—was reported in 27 cases, some of which were published as case reports and others as case series. Overall, there is a broad clinical spectrum with typically asymmetric manifestation and partly severe motor sequelae and partly mild courses. Lower limb paralysis appears to be more frequent than upper limb paralysis. An encephalitic component is not apparent in all cases

Case presentation

We herein add the case of a 29 year-old female who developed encephalitis and myelitis with flaccid paralysis during a long-time stay in Indonesia. Diagnostic workup in Indonesia did not clearly reveal an underlying cause. Upon clinical stabilization, the patient was evacuated to her home country Germany, where further diagnostics confirmed Japanese encephalitis virus as the causative agent. The patient has partly recovered, but still suffers from residual paralysis of the upper limb.

Conclusion

Flaccid paralysis is a rare, and likely underdiagnosed complication of Japanese encephalitis, which, to the best of our knowledge, has never been diagnosed outside endemic areas before.

Application of assisted portal under anterior horn of lateral meniscus for the treatment of discoid meniscus injury

PURPOSE

The assisted inferior anterolateral portal under anterior horn of the lateral meniscus (UAHLM portal) was applied to treat the lateral discoid meniscus injury conveniently and the clinical outcomes were evaluated.

METHODS

A retrospective review was conducted on 60 patients who underwent arthroscopic surgery with a symptomatic discoid lateral meniscus. Normal anterolateral/anteromedial portals assisted with UAHLM portal (1-2 cm inferior to the anterolateral portal) were used. All patients were followed up for 24-48 months (median, 33 months) and evaluated by MRI images and clinical outcomes including clinical findings, Lysholm scores and IKDC scores.

RESULTS

After meniscus plasty with or without repair, most of the upper layer of lateral meniscuses was retained. A total of 54 patients (16 males and 38 females, 42 ± 17.8 years old) showed satisfactory clinical results without requiring reoperation after a median follow-up time of 33 months. At final follow-up, a full range of motion was achieved in all patients. MRI indicated the thickness of anterior horn of lateral meniscus was (5.38 ± 1.09 mm) before the operation and (4.04 ± 0.71 mm) after the operation at the 2-year follow-up; clinical outcomes were improved significantly than the baseline: positive McMurray test (50 vs. 2, P< 0.001), Lysholm score (64.9 ± 9.0 vs. 94.7 ± 4.9, P< 0.001), and IKDC score (54.4 ± 7.7 vs. 92.6 ± 4.3, P< 0.001). No significant complication was observed during the follow-up.

CONCLUSION

Thus, this technique with assisted UAHLM portal was convenient for arthroscopic discoid meniscus plasty and meniscus repair and served as an effective method in patients with a symptomatic discoid lateral.

Visualization of the periventricular Virchow-Robin spaces with ependymal openings

PURPOSE

The morphological relationships between the periventricular Virchow-Robin spaces (VRSs) and cerebral ventricles have been poorly documented. The present study aimed to explore the issue using magnetic resonance imaging.

METHODS

A total of 211 patients were included in this study. T2-weighted and constructive interference in steady state (CISS) sequences were performed in thin-sliced, coronal sections.

RESULTS

On T2-weighted sequence, the periventricular VRSs with ependymal openings were identified in 34% of 139 subjects. All the openings were located in the lateral wall of the anterior horn. In CISS sequences, such VRSs were found in 39% of 72 subjects. The mean age was significantly higher in the population with such VRSs compared to those without VRSs (p = 0.0047). Of the 58 periventricular VRSs with ependymal openings identified on T2-weighted images, 16% were located in the upper, 36% in the middle, and 48% in the lower part of the lateral wall. Of the 38 such VRSs identified on CISS images, 32% were located in the upper, 24% in the middle, and 42% in the lower part of the lateral wall, and 3% in the upper part of the medial wall.

CONCLUSIONS

The ependymal openings of the periventricular VRSs may be centered in the lateral wall of the anterior horn. The coronal CISS sequence can sensitively delineate the VRSs with ependymal openings.

Evaluation of the size and position of the insertion of the anterior medial meniscus root in varus osteoarthritic knees

PURPOSE

Recent studies have suggested radial displacement of the medial meniscus as a cause of varus knee osteoarthritis (OA). Two anatomical studies reported that such displacement may be associated with anterior insertion of the medial meniscus anterior horn. It was aimed to evaluate the location and area of this insertion in patients with advanced knee OA.

METHODS

Medial meniscus anterior horn insertions were classified into four types, as described in a previously reported classification during 225 total knee arthroplasty (TKA) in 184 patients. The incidence rates of insertion type were compared with previously reported rates in nearly normal or non-arthritic knees. The insertion surface area was also measured during 158 TKAs.

RESULTS

Of the 225 knees, 82 (36.4 %), 93 (41.3 %), 35 (15.6 %), and 15 (6.7 %) were classified as I, II, III, and IV, respectively. An anteriorly inserted anterior horn was not more frequent in advanced varus OA knees than in previously reported nearly normal or non-arthritic knees. The insertion surface areas were 57.5 ± 18.9, 56.1 ± 16.0, and 56.4 ± 14.4 mm² for types I, II, and III, respectively; these areas did not differ significantly.

CONCLUSION

Since the incidence of an anteriorly inserted medial meniscus anterior horn was not higher in advanced varus OA knees than in normal or non-arthritic knees, an anteriorly inserted anterior horn may have little or no effect on the aetiology of varus OA knees. This study provides some information for clarifying the aetiology of knee OA.

LEVEL OF EVIDENCE

IV.