[Application of anterior region suture of popliteal hiatus in treatment of discoid lateral meniscus injury with instability in popliteal tendon region].

Objective: To discuss the application of anterior region suture of the popliteal hiatus (PH) under arthroscopy in the treatment of discoid lateral meniscus (DLM) injury with instability in the popliteal tendon region. Methods: The clinical data of 53 patients (56 knees) with DLM injury who met the selection criteria between March 2014 and November 2022 were retrospectively analyzed. There were 15 males and 38 females, aged 8-55 years with an average age of 36.5 years. Fourteen cases had a history of trauma, while the remaining 39 cases had no clear history of trauma. The disease duration ranged from 1 day to 6 years, with an average duration of 15.6 months. According to the Watanabe classification, there were 40 knees of complete type and 16 knees of incomplete type. The preoperative International Knee Documentation Committee (IKDC) knee joint score was 51.2±8.3, the Lysholm score was 59.6±11.2, and the visual analogue scale (VAS) score was 4.7±1.3. After the arthroscopic meniscal plasty, the instability of the popliteal tendon region meniscus was checked by probing traction. Subsequently, the Out-inside technique or a combination of Out-inside and All-inside techniques was used to suture the anterior region of the PH. The stability of the meniscus after suturing was assessed, and if necessary, further suturing using the All-inside technique at the posterior region of the PH, the posterior horn of the meniscus, and using the Out-inside technique at the anterior horn of the meniscus was performed. Postoperative complications were recorded. The effectiveness was evaluated using pre- and post-operative IKDC scores, Lysholm scores, and VAS scores. Results: After operation, knee joint pain, crepitus, and locking disappeared, with McMurray and grinding tests turning negative. All patients were followed up 12-93 months with an average of 57.5 months. There was no complication such as common peroneal nerve injury, deep vein thrombosis of the lower limbs, joint infection, or joint stiffness. At last follow-up, the IKDC knee joint score was 76.7±5.5, the Lysholm score was 94.0±4.1, and the VAS score was 1.1±0.8. The differences compared with preoperative scores were significant ( t=-22.090, P<0.001; t=-23.704, P<0.001; t=19.767, P<0.001). Conclusion: Suturing of the anterior region of the PH is crucial in the treatment of DLM injury with instability in the popliteal tendon region.

[A study on repair method of type â ¡c injury in lateral meniscus popliteal tendon area of porcine knee].

Objective: To investigate the repair method of type Ⅱc injury in the lateral meniscus popliteal tendon area based on the porcine knee joint. Methods: Eighteen commercially available fresh porcine knee joints were randomly divided into 3 groups ( n=6). After preparing a type Ⅱc injury in the lateral meniscus popliteal tendon area, and the anterior (group A), posterior (group B), or anterior and posterior (group C) of the popliteal hiatus (PH) was sutured by vertical mattress. The tension meter was used to apply gradient tensions of 2, 4, 6, 8, and 10 N along the tibial plateau horizontally, respectively, to pull the midpoint of the lateral meniscus popliteal tendon area. The displacement values before modeling, after modeling, and after suture were recorded. The reduction value of lateral meniscus displacement and reduction rate after suture were calculated and compared between groups. Results: There was no significant difference between groups ( P>0.05) in the displacement values before modeling, after modeling, and after suture under different tensions. There was no significant difference between groups A and C ( P>0.05) in the reduction value of lateral meniscus displacement and reduction rate after suture under different tensions. The reduction value of lateral meniscus displacement and reduction rate after suture in group B were lower than those in groups A and C. The reduction value of lateral meniscus displacement under tension of 2 N and the reduction rates under tensions of 2, 4, and 6 N between groups A and B showed significant differences ( P<0.05). The reduction value of lateral meniscus displacement and the reduction rate under tensions of 2, 4, and 6 N between groups B and C showed significant differences ( P<0.05). Conclusion: Suturing the anterior area of PH is the key to repairing type Ⅱc injury of lateral meniscus popliteal tendon area.

The continuous structure of the joint capsule and meniscus in the pig knee.

The knee joint capsules composed of a fibrous layer and a synovial layer. The knee meniscus consists of the superficial network, lamellar layer, tie fibre and circumferential bundles. However, the continuous structure of the knee joint capsule and meniscus has not been reported. Fetal and adult pigs were used to investigate the structural relationship between the stifle joint capsule and meniscus based on the gross anatomy and histological findings. In the gross anatomical examination, the joint capsule appeared to have separated attachments to the meniscus, except for the lower aspect of the popliteal hiatus. Histologically, the lower half of the popliteal hiatus was found to have separated attachments, with vessels running between the attachments of the joint capsules. The synovial layer of the joint capsule continued to the superficial network, and the fibrous layer of the joint capsule continued to the lamellar layer and tie fibres. There were two routes of arterial entry into the meniscus: intracapsular and intercapsular. It appeared that the presence of separated attachments of the joint capsule was necessary to allow the intercapsular route. This study clarified for the first time the routes of feeding vessels entering the meniscus and proposed to call this entry point the meniscus hilum. We consider that this detailed anatomical information is important for understanding the continuation between the joint capsule and the meniscus.

A study on repair method of type Ⅱc injury in lateral meniscus popliteal tendon area of porcine knee / 中国修复重建外科杂志

OBJECTIVE@#To investigate the repair method of type Ⅱc injury in the lateral meniscus popliteal tendon area based on the porcine knee joint.@*METHODS@#Eighteen commercially available fresh porcine knee joints were randomly divided into 3 groups ( n=6). After preparing a type Ⅱc injury in the lateral meniscus popliteal tendon area, and the anterior (group A), posterior (group B), or anterior and posterior (group C) of the popliteal hiatus (PH) was sutured by vertical mattress. The tension meter was used to apply gradient tensions of 2, 4, 6, 8, and 10 N along the tibial plateau horizontally, respectively, to pull the midpoint of the lateral meniscus popliteal tendon area. The displacement values before modeling, after modeling, and after suture were recorded. The reduction value of lateral meniscus displacement and reduction rate after suture were calculated and compared between groups.@*RESULTS@#There was no significant difference between groups ( P>0.05) in the displacement values before modeling, after modeling, and after suture under different tensions. There was no significant difference between groups A and C ( P>0.05) in the reduction value of lateral meniscus displacement and reduction rate after suture under different tensions. The reduction value of lateral meniscus displacement and reduction rate after suture in group B were lower than those in groups A and C. The reduction value of lateral meniscus displacement under tension of 2 N and the reduction rates under tensions of 2, 4, and 6 N between groups A and B showed significant differences ( P<0.05). The reduction value of lateral meniscus displacement and the reduction rate under tensions of 2, 4, and 6 N between groups B and C showed significant differences ( P<0.05).@*CONCLUSION@#Suturing the anterior area of PH is the key to repairing type Ⅱc injury of lateral meniscus popliteal tendon area.

Preoperative Magnetic Resonance Imaging as a Diagnostic Aid for Hypermobile Lateral Meniscus.

BACKGROUND: Hypermobile lateral meniscus is difficult to diagnose with imaging due to its absence of tears or anomalies. We aimed to clarify the accuracy of the preoperative diagnosis using magnetic resonance imaging (MRI). METHODS: The preoperative MRI status of the posterosuperior popliteomeniscal fascicle (sPMF), anteroinferior popliteomeniscal fascicle (iPMF), and popliteal hiatus were examined retrospectively on sagittal images in the hypermobile lateral meniscus group (n = 22) and an age- and gender-matched control group (n = 44). These statuses were evaluated by a logistic regression analysis to assess their degree of diagnostic accuracy. RESULTS: The area under the curve (AUC) of the sPMF, iPMF, popliteal hiatus, and all three criteria combined was 0.66, 0.74, 0.64, and 0.77, respectively (low, moderate, low, and moderate accuracy, respectively). The odds ratios of the most severe type 3 forms of the sPMF, iPMF, and popliteal hiatus for hypermobile lateral meniscus were significantly high (5.50, 12.20, and 5.00, respectively). Although the diagnostic accuracy was not high enough, the significantly higher odds ratio for type 3 may indicate a hypermobile lateral meniscus. CONCLUSION: a definitive diagnosis of hypermobile lateral meniscus is difficult with MRI findings alone; however, MRI evaluations of the iPMF, sPMF, and the widening of popliteal hiatus can be used as an adjunct to diagnosis.

[Arthroscopic classification and management for the popliteal hiatus of the lateral meniscus tears].

OBJECTIVE: To bring forward an arthroscopic classification of the popliteal hiatus of the lateral meniscus (PHLM) tears and to assess the effects of arthroscopic all-inside repair with suture hook in management of such injuries. METHODS: This study involved 146 patients who underwent arthroscopic operation because of PHLM tears from April 2014 to October 2017, eliminating the patients who had discoid lateral meniscus. There were 81 males and 65 females, with 54 left knees and 92 right knees. The average ages were (34.7±3.7) years. Among the selected participants, there were 107 patients with anterior cruciate ligament (ACL) injuries, 39 patients with medial collateral ligament (MCL) injuries, and 48 patients with medial meniscus tears. The average preoperative Lysholm and International Knee Documentation Committee (IKDC) scores were 57.7±9.2 and 54.1±8.9, respectively. The arthroscopic classification was based on the extent and degree of PHLM tears and using the arthroscopic all-inside repair with suture hook for such injuries. For the patients associated with ACL injuries, the ipsilateral autograft hamstring tendons use as the reconstruction graft for single bundle ACL reconstructions. The suture anchors were used for treatment of MCL Ⅲ injuries, and the arthroscopic all-inside repair for medial meniscus tears. RESULTS: A total of 146 PHLM tears in 146 patients were divided into type Ⅰ (tears not involved in popliteus tendon incisura; n=86, 58.9%), type Ⅱ (tears involved in popliteomeniscal fascicles; n=36, 24.7%), and type Ⅲ (tears involved in popliteus tendon incisura; n=24, 16.4%). For type Ⅰ, there were three subtypes, including type Ⅰa: longitudinal tear (n=53, 61.6%), type Ⅰb: horizontal tear (n=27, 31.4%), and type Ⅰc: radial tear (n=6, 7.0%). For type Ⅱ, there were also three subtypes, including type Ⅱa: anterosuperior popliteomeniscal fascicle tear (n=5, 13.9%), type Ⅱb: posterosuperior popliteomeniscal fascicle tear (n=20, 55.6%), and type Ⅱc: both tears (n=11, 30.6%). For type Ⅲ, there were two subtypes, including type Ⅲa: horizontal tear (n=9, 37.5%), type Ⅲb: radial tear (n=15, 62.5%). In the follow-up for an average of 15.3±2.6 months, all the patients had done well with significantly improved Lysholm (84.6±14.3) and IKDC (83.2±12.8) scores at the end of the last follow-up relative to preoperative scores (P > 0.01). CONCLUSION: We propose that it is possible to classify lateral meniscus tears at the popliteal hiatus region for three types, which can summarize the injury characteristics of this area. The arthroscopic all-inside repair with suture hook for the PHLM tears can avoid stitching to popliteal tendon or narrowing popliteal hiatus and have satisfactory clinical results.

Anatomy, magnetic resonance and arthroscopy of the popliteal hiatus of the knee: normal aspect and pathological conditions.

The popliteal hiatus is a complex region, formed by the confluence of various structures connecting the meniscus, popliteal tendon, tibia and fibula.The main structures that can be found are the three popliteomeniscal fascicles (anterior, postero-inferior and postero-superior), the lateral and posterior meniscotibial ligaments, the popliteofibular ligament and the meniscofibular fascicle.These structures can be identified in most cases using magnetic resonance imaging, and their 'static' assessment can be performed.Arthroscopic assessment is useful in identifying and testing 'dynamically' the integrity of the structures around the popliteal hiatus.Injuries or abnormalities of the popliteal hiatus and its structures could result in meniscal hypermobility and subluxation; however, these injuries are often unrecognized.Possible abnormalities in this region, apart from the well-known bucket-handle meniscal tear, are the Wrisberg Type III discoid meniscus, and meniscal fascicles tears. Cite this article: EFORT Open Rev 2021;6:61-74. DOI: 10.1302/2058-5241.6.200089.

Widening of the popliteal hiatus on sagittal MRI view plays a critical role in the mechanical signs of discoid lateral meniscus.

PURPOSE: This study was undertaken to elucidate the clinical significance of widening of the popliteal hiatus on magnetic resonance imaging (MRI) after a torn discoid lateral meniscus (DLM). METHODS: Included are 125 knees with meniscal disorders after arthroscopic surgery, divided according to preoperative MRI and symptoms into group A (torn DLM with mechanical symptoms,11 knees); group B (torn DLM without mechanical symptoms,41 knees); group C (asymptomatic DLM, 19 knees); and group D (medial meniscal tears, 54 knees). Popliteal hiatus width was measured on sagittal and coronal MRI. During arthroscopy, total meniscectomy or central partial meniscectomy combined repair of the remaining part was performed in group A and group B. Outcomes were evaluated with MRI, the Tegner, Lysholm Knee Scoring Scale, and visual analog scale (VAS) scores. RESULTS: The preoperative width of the popliteal hiatus was significantly larger in group A than in groups C and D (P < 0.05) on both views. Group A had a wider popliteal hiatus on sagittal view compared with group B (P < 0.05); group B had a wider popliteal hiatus on coronal view compared with group D (P < 0.05). The width of the popliteal hiatus on sagittal view was significantly reduced after surgery in group A (P < 0.05). In groups A and B, Lysholm and Tegner scores were improved, while VAS scores were reduced (all P < 0.05). CONCLUSION: Widening of the popliteal hiatus on MRI was correlated with torn DLM and accompanied mechanical symptoms. Arthroscopic central partial menisectomy and stabilization of the posterior part of the middle body anterior to the popliteus tendon were effective for the treatment of torn DLM. These findings may help guide appropriate treatment for torn DLM. LEVEL OF EVIDENCE: II.

Tears of the Popliteomeniscal Fascicles of the Lateral Meniscus: An Arthroscopic Classification.

OBJECTIVE: To bring forward an arthroscopic classification of the popliteomeniscal fascicles of the lateral meniscus (PFLM) tears. DESIGN: Six fresh frozen knee joint samples of adult males were chosen, and the lateral meniscus at the popliteal hiatus region were measured to analyze their anatomic relationship. Patients who had received magnetic resonance imaging scan at knee joint before the surgery and diagnosed as PFLM tears by arthroscopy from April 2014 to October 2017 were selected. Data regarding the integrity of PFLM were prospectively recorded in a data registry. Tear morphology and treatment received were subsequently extracted by 2 independent reviewers from operative notes and arthroscopic surgical photos. RESULTS: The average length and thickness of the popliteal hiatus of the lateral meniscus were 2.09 ± 0.21 cm and 0.43 ± 0.08 cm, respectively. The average length of anterosuperior popliteomeniscal fascicle (APF) was 0.87 ± 0.18 cm, and the posterosuperior popliteomeniscal fascicle (PPF) was 0.72 ± 0.15 cm. A total of 36 PFLM tears in 36 patients were divided as type I (APF tear; n = 5, 13.9%), type II (PPF tear; n = 20, 55.6%), and type III (both APF and PPF tears; n = 11, 30.6%). All patients were treated with arthroscopic all-inside repair using a suture hook for the PFLM tears and follow-up for 21.1 months. All patients have done well with significantly improved Lysholm and International Knee Documentation Committee scores at the last follow-up relative to preoperative scores (P < 0.01). CONCLUSION: This study suggests to possibly classify the PFLM tears for clinical practice.

Arthroscopic classification and management for the popliteal hiatus of the lateral meniscus tears / 北京大学学报(医学版)

OBJECTIVE@#To bring forward an arthroscopic classification of the popliteal hiatus of the lateral meniscus (PHLM) tears and to assess the effects of arthroscopic all-inside repair with suture hook in management of such injuries.@*METHODS@#This study involved 146 patients who underwent arthroscopic operation because of PHLM tears from April 2014 to October 2017, eliminating the patients who had discoid lateral meniscus. There were 81 males and 65 females, with 54 left knees and 92 right knees. The average ages were (34.7±3.7) years. Among the selected participants, there were 107 patients with anterior cruciate ligament (ACL) injuries, 39 patients with medial collateral ligament (MCL) injuries, and 48 patients with medial meniscus tears. The average preoperative Lysholm and International Knee Documentation Committee (IKDC) scores were 57.7±9.2 and 54.1±8.9, respectively. The arthroscopic classification was based on the extent and degree of PHLM tears and using the arthroscopic all-inside repair with suture hook for such injuries. For the patients associated with ACL injuries, the ipsilateral autograft hamstring tendons use as the reconstruction graft for single bundle ACL reconstructions. The suture anchors were used for treatment of MCL Ⅲ injuries, and the arthroscopic all-inside repair for medial meniscus tears.@*RESULTS@#A total of 146 PHLM tears in 146 patients were divided into type Ⅰ (tears not involved in popliteus tendon incisura; n=86, 58.9%), type Ⅱ (tears involved in popliteomeniscal fascicles; n=36, 24.7%), and type Ⅲ (tears involved in popliteus tendon incisura; n=24, 16.4%). For type Ⅰ, there were three subtypes, including type Ⅰa: longitudinal tear (n=53, 61.6%), type Ⅰb: horizontal tear (n=27, 31.4%), and type Ⅰc: radial tear (n=6, 7.0%). For type Ⅱ, there were also three subtypes, including type Ⅱa: anterosuperior popliteomeniscal fascicle tear (n=5, 13.9%), type Ⅱb: posterosuperior popliteomeniscal fascicle tear (n=20, 55.6%), and type Ⅱc: both tears (n=11, 30.6%). For type Ⅲ, there were two subtypes, including type Ⅲa: horizontal tear (n=9, 37.5%), type Ⅲb: radial tear (n=15, 62.5%). In the follow-up for an average of 15.3±2.6 months, all the patients had done well with significantly improved Lysholm (84.6±14.3) and IKDC (83.2±12.8) scores at the end of the last follow-up relative to preoperative scores (P > 0.01).@*CONCLUSION@#We propose that it is possible to classify lateral meniscus tears at the popliteal hiatus region for three types, which can summarize the injury characteristics of this area. The arthroscopic all-inside repair with suture hook for the PHLM tears can avoid stitching to popliteal tendon or narrowing popliteal hiatus and have satisfactory clinical results.

Arthroscopic all-inside repair with suture hook for horizontal tear of the lateral meniscus at the popliteal hiatus region: a preliminary report.

BACKGROUND: Arthroscopic surgery procedures vary depending on the types of meniscus tear, including meniscectomy and meniscus repair. Among the several types of meniscus tear, the horizontal tear of the lateral meniscus at the popliteal hiatus region is a common injury, and its surgical treatment is still inconsistent. METHODS: Between January 2018 and October 2018, 20 patients who underwent all-inside repair with suture hook for the horizontal tear of the lateral meniscus at the popliteal hiatus region were recruited. Any operative complication was recorded, and postoperative MRI scans were conducted at the 6 months. The clinical results were graded based on the scale of the Lysholm knee score preoperatively and at follow-up. RESULTS: No operative complications were recorded. Postoperative MRIs at the 6 months showed that there was no re-tear for all patients, though signal intensity remained high in T2-weighted MRI in the lateral meniscus for nine cases. The average preoperative Lysholm knee score was 58.6 ± 10.1, which increased significantly to 89.3 ± 7.8 (t = - 11.01, p = 0.001) at the last follow-up. Recurrence or aggravation of symptoms was not noted at the final follow-up. CONCLUSION: All-inside repair with suture hook may be a good option for the horizontal tear of the lateral meniscus at the popliteal hiatus region which preserves the meniscus; avoids iatrogenic injury on the adjacent popliteal tendon, common peroneal nerve, and inferior lateral geniculate artery.

Widening of the popliteal hiatus on magnetic resonance imaging leads to recurrent subluxation of the lateral meniscus.

PURPOSE: This study was undertaken to elucidate the clinical significance of widening of the popliteal hiatus on magnetic resonance imaging (MRI), and to document the clinical results and technical aspects of arthroscopic repair of this finding. METHODS: Included are 82 knees after arthroscopic surgery, divided according to arthroscopic diagnosis into group A, hypermobility of lateral meniscus, 8 knees; group B, tear of the anterior horn of the lateral meniscus, 32 knees; and group C, no abnormality of the lateral meniscus, 36 knees with medial meniscal tears and 6 with other conditions. Popliteal hiatus diameter was measured and the popliteal hiatus/lateral tibial plateau (LTP) ratio was calculated on preoperative sagittal and coronal MRI. At arthroscopy, the widened popliteal hiatus in group A was tightened anteriorly by outside-in or all-inside suture and posteriorly with all-inside suture. Outcomes were evaluated with MRI, Lysholm, Tegner and VAS scores. RESULTS: The preoperative diameter of the popliteal hiatus and the popliteal hiatus/LTP ratio were significantly larger in group A than in groups B and C (p < 0.05) on both views. Threshold popliteal hiatus/LTP values of 0.16 and 0.18 on the sagittal and coronal views demonstrated diagnostic discrimination, and these values were significantly reduced after arthroscopy in Group A. Lysholm and Tegner scores were improved after tightening of the popliteal hiatus, while VAS scores reduced (all p < 0.05). CONCLUSION: Widening of the popliteal hiatus on MRI may lead to recurrent subluxation of the lateral meniscus. Arthroscopic anterior and posterior tightening of the popliteal hiatus was a safe and effective treatment. LEVEL OF EVIDENCE: II.

Arthroscopic meniscus repair for recurrent subluxation of the lateral meniscus.

PURPOSE: This study was undertaken to diagnose and to document the clinical results and technical aspects of arthroscopic meniscus repair for recurrent subluxation with peripheral tears around the popliteal hiatus of the lateral meniscus. METHODS: Twenty-three patients (24 knees) with symptomatic recurrent subluxation of the lateral meniscus treated by arthroscopic meniscus repair were included. The inclusion criteria were: (1) patients with knee pain, locking or snapping symptoms despite 3 months of conservative treatment; (2) non-discoid lateral meniscus; (3) stable knee, and (4) tears involving the red-white or red-red zone. All tears were repaired by either the modified all-inside suture technique only or a combination of the modified all-inside and modified outside-in suture techniques. Clinical results were evaluated preoperatively and at final follow-up according to Tegner activity level, Lysholm knee, and Hospital for Special Surgery (HSS) scores. RESULTS: No reoperations were required after a median follow-up of 41 months (range 24-124). Although recurrence of a locking episode was documented in one knee and catching sensations were experienced in three knees, those patients did not require reoperation. At the last follow-up, the median Tegner activity level had improved significantly from 4 (range 2-6) to 7 (range 3-10, p < 0.0001), the median Lysholm knee score improved from 76 (range 25-90) preoperatively to 94 (range 76-100) at final follow-up (p < 0.0001), and the median preoperative HSS score improved from 86 to 95 at final follow-up (p < 0.0001). CONCLUSION: The described arthroscopic meniscus suture technique is effective for treating symptomatic recurrent subluxation of the lateral meniscus without any complications or recurrence. Clinical suspicion and understanding of recurrent subluxation with lateral meniscus are important to diagnose the disease especially when definite meniscal tear signs are absent on magnetic resonance imaging. LEVEL OF EVIDENCE: IV.

Arthroscopic Evaluation of Posterolateral Rotatory Instability of the Knee / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to confirm the efficacy of arthroscopic findings for the diagnosis of posterolateral rotatory instability (PLRI) of the knee. MATERIALS AND METHODS: We retrospectively evaluated 27 patients (28 cases) who had been operated upon for PLRI between February 1998 and June 2001. All patients underwent preoperative or intraoperative arthroscopic examinations including anterior/posterior cruciate ligament, popliteus tendon, inferior and superior popliteomeniscal fascicle, popliteofibular ligament, lateral meniscus, instability and abnormal popliteomeniscal motion for internal and external rotation. RESULTS: Instability, which means popliteal hiatus widening during internal rotation of the tibia, was identified in all cases (100%). Tear of the inferior and superior popliteomenical fascicle was identified in 24 cases (86%) and abnormal popliteomeniscal motion during rotation was identified in 20 cases (71%). Popliteus tendons were abnormal in 18 cases (65%) with 5 cases (19%) of complete tear and 13 cases (46%) of partial tear or elongation. CONCLUSION: These results suggest that arthroscopic evaluation of the popliteal hiatus structures in the patients suspected for PLRI of the knee is helpful for diagnosis and the determination of treatment modality.