The pie-crusting release of the medial collateral ligament in arthroscopic partial meniscectomy is associated with improved clinical outcomes without altering radiological measurements.

PURPOSE: The aim of this study was to evaluate how the pie-crusting technique affects clinical and radiological outcomes in patients undergoing arthroscopic partial meniscectomy. METHODS: A total of 68 patients with Kellgren-Lawrence (K-L) grade 2 who underwent arthroscopic partial meniscectomy between 2015 and 2021 were evaluated and divided into two groups as arthroscopic partial meniscectomy (36 patients) and arthroscopic partial meniscectomy with pie-crusting (32 patients) according to whether the pie-crusting technique was applied or not. All patients were evaluated at a minimum 2-year follow-up in terms of Lysholm score, Tegner activity score, International Knee Documentation Committee (IKDC) score and Visual Analogue Scale (VAS) score. To assess the impact of the pie-crusting technique, radiological measurements were conducted using radiographs taken before and after pie-crusting, as well as postoperative radiographs. RESULTS: Lysholm, Tegner, IKDC and VAS scores exhibited statistically significant differences after surgery compared to preoperative evaluations in both groups (p < 0.05). Furthermore, these scores were significantly superior in the arthroscopic partial meniscectomy with pie-crusting group compared to the arthroscopic partial meniscectomy group at 24 months postoperatively (p < 0.05). While the radiological measurements in the arthroscopic partial meniscectomy with pie-crusting group showed statistically significant differences before and after pie-crusting (p < 0.05), no significant difference was observed between before pie-crusting and 12 and 24 months postoperatively (n.s.). CONCLUSION: The current study is the first to demonstrate the true effectiveness of the pie-crusting technique. The application of the pie-crusting technique when necessary results in a statistically significant improvement in clinical scores without affecting radiological measurements for patients undergoing arthroscopic partial meniscectomy compared to not utilising it. LEVEL OF EVIDENCE: Level III.

Ultrasound-guided treatment of medial collateral ligament calcification of the knee with TenJet™: a case report.

Calcification of the medial collateral ligament is a rare cause of medial knee pain along with functional impairment. Most cases are asymptomatic but those that are symptomatic typically respond to conservative management. However, in those instances with persistent symptoms that desire further intervention but want to minimize the risks associated with surgery, we present a novel approach for calcium removal with an ultrasound-guided percutaneous needle tenotomy with TenJet™ as a reasonable treatment modality.

Atelocollagen Injections Improve Outcomes in the Nonsurgical Treatment of Grade III Medial Collateral Ligament Injuries.

Background: The purpose of this study was to evaluate the clinical outcomes of atelocollagen injections in isolated grade III medial collateral ligament (MCL) injuries of the knee joint. Methods: A total of 50 participants were included in this retrospective study. Twenty-six patients underwent conservative treatment with a single atelocollagen injection, while the remaining patients underwent only typical conservative treatment. All participants underwent magnetic resonance imaging to identify and grade MCL injury. Valgus stress radiography was performed on both knees at 6 and 12 months after the injury. The visual analog scale (VAS) score was collected at the first visit and at 2 weeks, 6 weeks, 6 months, and 12 months after injury. The International Knee Documentation Committee (IKDC) formula activity level and Lysholm score were evaluated for patient-reported outcomes at the first visit and at 6 and 12 months after injury. The participant's return to the pre-injury activity level ratio was measured by comparing the IKDC formula activity level at 12 months after the injury with that before the injury. Results: The VAS and Lysholm scores improved over time in both groups. The VAS and Lysholm scores were significantly better in the collagen injection group than in the control group. Regarding the activity level, the collagen injection group showed significantly better results at the 6-month follow-up, but there was no significant difference at the 12-month follow-up. The medial gap in the injured knee and the side-to-side difference (SSD) in both groups gradually decreased over time. The SSD in the collagen injection group was significantly smaller than that in the control group. Conclusions: Atelocollagen injections resulted in better clinical and radiologic outcomes along with a higher rate of return to the pre-injury activity level, thereby exhibiting a positive effect in the nonsurgical treatment of grade III MCL injuries.

Medial collateral ligament injury of the knee: correlations between MRI features and clinical gradings.

OBJECTIVE: To evaluate the degree of correlation between MRI and clinical gradings of medial collateral ligament (MCL) injuries and assess for associated structures on MRI which may influence the clinical perception of MCL laxity. MATERIALS AND METHODS: All knee MRIs with acute MCL injuries between 2016 and 2020 at our centre were retrospectively reviewed by two blinded musculoskeletal radiologists. The clinic notes were reviewed for clinical gradings. RESULTS: One hundred and nineteen MRIs included. Forty-eight percent (57/119) agreement between MRI and clinical gradings (κ = 0.21, standard error (SE) 0.07). MRI grades: I 29% (34/119), II 50% (60/119), III 21% (25/119). Clinical grades: I 67% (80/119), II 26% (31/119), III 7% (8/119). In patients with clinical grade III MCL injury, there was waviness of the superficial MCL on MRI in 100% (8/8), deep meniscofemoral ligament tear in 75% (6/8), anterior cruciate ligament (ACL) partial or complete tear in 75% (6/8) and posteromedial corner (PMC) injury in 100% (8/8); compared with 0% (0/111), 34% (38/111), 44% (49/111) and 41% (46/111) respectively in clinical grade I or II injuries (p < 0.05). CONCLUSION: Agreement between MRI and clinical gradings of MCL injuries was only 'fair', with MRI almost always overestimating the grade of the injury when there was a mismatch. Waviness of the superficial MCL and injuries to the deep MCL, ACL and PMC correlate with clinical instability.

Arthroscopically assisted repair of the medial collateral ligament of the knee: A case report, description of a new technique.

Tears of the medial collateral ligament of the knee are common and often managed non-operatively [1]. Grade 3 tears that fail to heal are often treated with surgical repair through an open incision on the medial aspect of the knee. Many other ligament injuries of the knee are now managed with arthroscopic surgery. This has not yet been described for medial collateral ligament injuries of the knee. We describe a new arthroscopically assisted technique for MCL repair after grade III injury which avoids some of these complications.

Impact of intraoperative medial collateral ligament injury on outcomes after total knee arthroplasty: a meta-analysis and systematic review.

BACKGROUND: As an uncommon but severe complication, medial collateral ligament (MCL) injury in total knee arthroplasty (TKA) may be significantly under-recognized. We aimed to determine whether MCL injury influences postoperative outcomes of patients undergoing TKA. METHODS: Two independent reviewers searched PubMed, Cochrane Library, and EMBASE from their inception to July 1, 2021. The main outcomes were postoperative function, and secondary outcomes included the incidences of revision and complications. RESULTS: A total of 403 articles yielded 15 studies eligible for inclusion with 10 studies used for meta-analysis. This study found that there was a statistically significant difference in postoperative functional scores, range of motion (ROM), complications, and revision rates, with adverse outcomes occurring more commonly in patients with MCL injury. CONCLUSIONS: This meta-analysis highlights the complexity of MCL injury during TKA and shows the impact on postoperative function, joint mobility, complications, and revision. Surgeons need to prevent and put more emphasis on MCL injury during TKA.

Knee Dislocation With Acute Anterior Cruciate Ligament Reconstruction and Posterior Cruciate Ligament and Medial Collateral Ligament Repair.

SUMMARY: This video depicts the materials and steps for the repair of a Schenck classification KD III multiligamentous injury in a patient who had bilateral injuries after his car pinned him to a cabinet in his garage. The video demonstrates acute allograft reconstruction of anterior cruciate ligament and primary repair of the avulsions of posterior cruciate ligament and medial collateral ligament in the patient.

Measuring stiffness of normal medial collateral ligament in healthy volunteers via shear wave elastography.

PURPOSE: We aim to determine a reference data set for normal medial collateral ligament (MCL) stiffness values using shear wave elastography (SWE). METHODS: Quantitative stiffness of the MCL was measured at three levels: the proximal (MCL area from the level of the medial meniscus to the level of the femoral attachment), the middle (MCL area at the level of the medial meniscus), and the distal (MCL area from the level of the medial meniscus to the level of the tibial attachment) segments of the MCL at a knee position of 0°. RESULTS: A total of 60 MCL of 30 healthy volunteers (15 female, 15 male) were examined. The mean stiffness values of the proximal, middle, and distal MCL for observer 1 were 32.25 ± 6.44, 34.25 ± 6.84, and 35.47 ± 6.98, respectively. The mean stiffness values of the proximal, middle, and distal MCL for observer 2 were 33.56 ± 6.76, 35.44 ± 6.91, and 36.32 ± 7.04, respectively. CONCLUSION: SWE has a strong potential to be a method of choice for evaluating MCL stiffness. Our study participants were healthy volunteers and the data can be used as reference data for future studies.

Magnetic resonance imaging of medial collateral ligament avulsion fractures of the knee in children: a potentially underestimated injury.

BACKGROUND: Literature regarding medial collateral ligament (MCL) injuries is focused on adults with superficial MCL disruptions. However, children follow different injury patterns, with avulsion fractures at ligament attachment sites occurring commonly. Such avulsions have not been characterized for pediatric MCL injuries. OBJECTIVE: To elucidate imaging findings, and review management and outcomes of pediatric MCL avulsion fractures. MATERIALS AND METHODS: We conducted a 10-year retrospective review of knee magnetic resonance (MR) imaging reports for patients younger than 16 years old diagnosed with acute MCL avulsion fracture. MR imaging was reviewed to confirm and characterize the components of the avulsion (perichondrium without or with cartilage, and/or bone) and to identify additional knee injuries. Radiographs, if available, from the time of injury were reviewed. Clinical management and patient outcomes were recorded. RESULTS: Eighteen patients (13 boys, 5 girls) incurred an acute MCL avulsion fracture. All avulsions involved the deep MCL attachment: 17 meniscofemoral and 1 meniscotibial component. Two avulsions also included the superficial MCL attachment. Nine boys had non-osseous avulsions, all radiographically occult. All girls had radiographically apparent avulsions. Three girls and three boys sustained associated knee derangements, most commonly anterior cruciate ligament (ACL) injury (n=4). All MCL avulsions were initially treated conservatively; one child required subsequent surgery for ongoing pain. CONCLUSION: Pediatric MCL avulsion fractures in this study uniformly involve the attachment of the deep MCL and can be entirely non-osseous, particularly in boys who lag in skeletal maturity, making these injuries radiographically occult. MR imaging may be required to recognize these avulsions, which can impact the duration of rest and knee bracing.

Treatment of medial-sided injuries in patients with early bicruciate ligament reconstruction for knee dislocation.

PURPOSE: In knee dislocation with bicruciate ligament and medial side injury (KDIIIM), treatment method of medial side injuries is controversial. The purpose of this study was to evaluate the outcomes of non-operative treatment of proximal and midsubstance and operative treatment of distal avulsion medial collateral ligament (MCL) ruptures in patients with early bicruciate reconstruction. METHODS: One-hundred and forty-seven patients with a knee dislocation and bicruciate ligament injury (KDII-KDV) were identified. Sixty-two patients had KDIIIM injury. Of these, 24 patients were excluded and 13 were lost to follow-up. With a minimum of 2 years of follow-up, IKDC2000 (subjective and objective), Lysholm and Tegner scores and stress radiographs were recorded. RESULTS: Twenty-five patients were available for follow-up: 18 had a proximal or midsubstance grade-III MCL rupture (proximal MCL group) and 7 had a distal MCL avulsion (distal MCL group). In the proximal MCL and distal MCL groups, respectively, median IKDC2000 subjective scores were 80 (range 57-99) and 62 (range 39-87), and median Lysholm scores were 88 (range 57-99) and 75 (range 40-100). The median medial opening (side-to-side difference) was 2.4 mm (range 0.1-9.2) in the proximal MCL group and 2.5 mm (range 0.2-4.8) in the distal MCL group. CONCLUSION: We found acceptable recorded outcomes in patients who underwent non-operative treatment of proximal and midsubstance grade-III MCL rupture and operative treatment of distal MCL avulsion with early bicruciate ligament reconstruction. LEVEL OF EVIDENCE: Level IV.

Influence of Intraoperative Medial Collateral Ligament Bony Avulsion Injury on the Outcome of Primary Total Knee Arthroplasty.

BACKGROUND: The purpose of this study is (1) to find the clinical and radiological outcome of intraoperative bony avulsion of medial collateral ligament (MCL) treated with screw and washer construct and (2) to predict the preoperative factors which may contribute to the avulsion-type MCL injury during primary total knee arthroplasty (TKA). METHODS: Intraoperative MCL avulsion injury occurred in 46 (0.8%) of the 4916 consecutive primary TKA from January 2011 to December 2015. After exclusion, the 41 knees were matched 1:2 with controls without MCL injury and compared for the various clinical, radiological, and functional parameters. The clinical parameters analyzed were age, gender, body mass index, preoperative diagnosis like osteoarthritis or rheumatoid arthritis, range of motion, sagittal deformity, and vitamin D levels. The radiological parameters calculated were coronal deformity, proximal tibial varus angle, distal femur valgus angle, joint line congruence angle, posterior tibial slope, "cup and saucer" morphology, presence or absence of knee subluxation, tibia vara, and femoral bowing. The preoperative and postoperative Knee Society Score and Knee Society Functional Score were analyzed. Complications or revisions, if any, were noted during the follow-up. Multivariate logistic regression analysis was used to predict the preoperative risk factors for MCL avulsion injury. RESULTS: At a mean follow-up of 58.4 ± 19.3 months, there were no radiological or physical examination findings of instability. Compared to the preoperative disability, there was a statistically significant improvement in clinical scores (Knee Society Score and Knee Society Functional Score) in the final follow-up (P < .001) in both cases and the control group. The mean preoperative coronal deformity was 170.6 ± 6.96 in the study group and 167.7 ± 4.3 in the control group (P = .021). The mean preoperative tibial slope was 10.5 ± 4.9 in the study group and 7.91 ± 4.15 in the control group (P = .003). The preoperative knee subluxation was present in 48.8% knees (P < .001) and "cup and saucer" morphology in 68.3 knees (P < .001) in the study group. The adjusted odds of MCL avulsion injury were greater for severe varus deformity (odds ratio [OR] 1.462, 95% confidence interval [CI] 1.15-1.86), knee subluxation (OR 39.78, 95% CI 3.78-418.86), and "cup and saucer" morphology (OR 33.11, 95% CI 5.69-192.66). CONCLUSION: Intraoperative MCL bony avulsion injury can be managed successfully with screw and washer construct without the need for increased prosthetic constraint in primary TKA. The presence of severe varus deformity, knee subluxation, and "cup and saucer" morphology tend to have an increased chance of MCL avulsion injury.

The bone attachments of the medial collateral and posterior oblique ligaments are defined anatomically and radiographically.

PURPOSE: To define the bony attachments of the medial ligaments relative to anatomical and radiographic bony landmarks, providing information for medial collateral ligament (MCL) surgery. METHOD: The femoral and tibial attachments of the superficial MCL (sMCL), deep MCL (dMCL) and posterior oblique ligament (POL), plus the medial epicondyle (ME) were defined by radiopaque staples in 22 knees. These were measured radiographically and optically; the precision was calculated and data normalised to the sizes of the condyles. Femoral locations were referenced to the ME and to Blumensaat's line and the posterior cortex. RESULTS: The femoral sMCL attachment enveloped the ME, centred 1 mm proximal to it, at 37 ± 2 mm (normalised at 53 ± 2%) posterior to the most-anterior condyle border. The femoral dMCL attachment was 6 mm (8%) distal and 5 mm (7%) posterior to the ME. The femoral POL attachment was 4 mm (5%) proximal and 11 mm (15%) posterior to the ME. The tibial sMCL attachment spread from 42 to 71 mm (81-137% of A-P plateau width) below the tibial plateau. The dMCL fanned out anterodistally to a wide tibial attachment 8 mm below the plateau and between 17 and 39 mm (33-76%) A-P. The POL attached 5 mm below the plateau, posterior to the dMCL. The 95% CI intra-observer was ± 0.6 mm, inter-observer ± 1.3 mm for digitisation. The inter-observer ICC for radiographs was 0.922. CONCLUSION: The bone attachments of the medial knee ligaments are located in relation to knee dimensions and osseous landmarks. These data facilitate repairs and reconstructions that can restore physiological laxity and stability patterns across the arc of knee flexion.

Arthroscopic pie-crusting release of the posteromedial complex of the knee for surgical treatment of medial meniscus injury.

BACKGROUND: An arthroscopic narrow posteromedial gap of the knee may cause failure of a meniscus operation. The posteromedial complex (PMC) of the knee, including the posterior part of the medial collateral ligament (MCL) and the posterior oblique ligament (POL), has a restrictive effect on the opening of the posteromedial gap of the knee in the half-extension position. Thus, we evaluated the radiological and clinical results of pie-crusting release of the PMC for arthroscopic meniscal surgery in tight knees. METHODS: Sixty patients with posterior injury of the medial meniscus were reviewed. All patients accepted arthroscopic pie-crusting release of the PMC. Fourty patients accepted meniscoplasty, and 20 patients accepted meniscal suturing. To evaluate the arthroscopic opening of the medial gap in 20° half-extension under 11-kg valgus stress, the width of the medial space before and after release were measured. During follow-up, the medial stability was evaluated by radiographic measurements of the joint space width (JSW) in 20° half-extension. Magnetic resonance imaging (MRI) was conducted to evaluate healing of the MCL and meniscus. Knee functions were evaluated using VAS (visual analogy score), Lysholm, IKDC (International Knee Documentation Committee) and Tegner scoring systems. RESULTS: In all patients, meniscus operations were performed without iatrogenic cartilage injury. After PMC release, the arthroscopic width of the medial space was 5.7 ± 0.5 mm, larger than that before release (2.5 ± 0.5 mm, p < 0.01). The follow-up time was 21.93 ± 7.04 months, there was no residual valgus laxity of the knee. The radiographic JSW was 5.97 ± 0.8 mm preoperatively, 9.2 ± 1.1 mm in the 1st week postoperatively, and 6.1 ± 0.9 mm by the 3rd postoperative month, showing no differences between preoperative and 3 months postoperative measurement (p > 0.05). For sutured meniscus, MRI showed healing in 15 patients while five had two-grade abnormal signals. VAS, Lysholm, IKDC and Tegner scores were 1.80 ± 0.51, 80.08 ± 3.74, 82.17 ± 4.64 and 5.48 ± 0.59, respectively, showing significant differences compared with the preoperative scores (5.57 ± 0.69, 48.17 ± 4.22, 51.42 ± 4.02 and 3.20 ± 0.68, respectively, p< 0.01). CONCLUSIONS: Pie-crusting release of the PMC can increase the posteromedial space and improve the visual field of the knee under arthroscopy, while neither causing no residual valgus instability of the knee nor affecting the clinical outcome at the final follow-up.

Presence of magnetic resonance imaging verified soft tissue injuries did not significantly affect the patient-reported outcome 12 months following a lateral tibial plateau fracture: A 12-month prospective cohort study of 56 patients.

BACKGROUND: Soft tissue injuries following lateral tibial plateau fracture affect more than half of patients. Regardless of the type of soft tissue injured, it is still unclear how different treatment strategies influence postoperative outcome. The aim of this study was to report the 12-month Knee Injury and Osteoarthritis Outcome Score (KOOS5) of patients with surgically managed lateral tibial plateau fractures divided into groups with and without conservatively managed magnetic resonance imaging (MRI)-verified soft tissue injuries. METHODS: Prospective cohort study. Patients treated surgically following a lateral tibial plateau fracture (AO-41B) between December 2013 and November 2016 were included. Soft tissue injuries were evaluated with preoperative MRI scans. The primary outcome score was the 12-month KOOS5 score divided into groups with and without soft tissue injuries. RESULTS: A total of 56 patients were included. Average patient age was 56 years (range 22-86). Thirty-three patients (59%) were female. Fifty percent of patients presented with MRI-verified soft tissue injuries. At 12 months postoperatively, the mean KOOS5 score for patients with soft tissue injuries was 53.5 (95% confidence interval (CI): 44.8-62.1) and the KOOS5 score for patients without soft tissue injuries was 59.6 (95% CI: 50.7-68.6). No significant difference in the KOOS5 score between patients with and without soft tissue injuries was observed (P = .31). CONCLUSIONS: At 12-month follow-up the presence of MRI-verified soft tissue injuries did not significantly affect the patient-reported KOOS5 score. More research is needed to investigate the effects of surgical vs. non-surgical treatment strategies of associated soft tissue injuries following lateral tibial plateau fractures.

Medial-Sided Injuries in the Multiple Ligament Knee Injury.

Multiligament knee injuries (MLKI) are complex and challenging to treat. The posteromedial corner (PMC) structures are commonly torn in MLKI. A thorough and systematic evaluation is imperative to avoid a missed diagnosis and for planning treatment. With several structures injured, the treatment method (operative vs. nonoperative, repair vs. reconstruction), availability of allografts, timing of surgery, and rehabilitation are some of the factors that have to be considered in the decision-making. Persistent valgus instability because of untreated or not healed medial collateral ligament (MCL) tears will increase graft forces on the cruciate ligament grafts, thus increasing the risk of reconstruction graft failure. In recent years, there has been a growing body of literature on the anatomy and biomechanics of the medial structures that has aided in the development of biomechanically and clinically validated anatomic PMC reconstructions. Despite good healing potential of the MCL, in MLKI, surgical treatment is recommended for grade III PMC injuries to aid early rehabilitation and reduce the risk of surgical failure. Several studies have reported satisfactory outcomes after surgical treatment of MLKI involving the medial side. Early functional rehabilitation is imperative to reduce the risk of arthrofibrosis.

Collateral Ligament Knee Injuries in Pediatric and Adolescent Athletes.

BACKGROUND: The majority of research on medial (MCL) and lateral (LCL) collateral ligament injuries has focused on adults and combined collateral/cruciate injuries. The purpose of this study was to determine characteristics associated with isolated collateral ligament injuries in adolescents, and assess timing for return to sports. METHODS: Electronic medical records were queried to identify patients aged below 17 years who sustained a magnetic resonance imaging-confirmed isolated MCL or LCL injury over an 8-year period. Retrospective review then documented patient and injury characteristics and clinical course. General linear modeling was used to analyze risk factors for prolonged return to sports, continued pain or reinjury. RESULTS: Fifty-one knees (33 in males, 65%), mean age 13.8 years (range, 5 to 17), were identified, of which 40 (78%) had MCL injuries. Over half (29, 57%) of knees had an open distal femoral physis including all 5 bony avulsion injuries. Eleven (22%) had LCL injuries of which 3 (6%) had concurrent posterolateral corner injuries. Forty-two (82%) knees had injuries that occurred during sports. Eleven knees (28%) with MCL tears had a simultaneous patellar instability episode. Knee injuries that occurred during sports had 37% shorter recovery time (P=0.02). Eight knees (16%) experienced a reinjury and 12 (24%) were followed over an extended period of time for various knee issues. Football injuries were more likely to be grade 3 (P=0.03), and football and soccer accounted for all grade III injuries. The mean return to sports was 2.2 months, with grade III cases returning at 2.4 months, and 95% of cases within 4 months. CONCLUSIONS: Isolated collateral ligament injuries are rare in adolescent athletes. MCL injuries, one-quarter of which occurred in conjunction with patellar instability events, were 4 times more common than LCL injuries, one quarter of which have other posterolateral corner structures involved. Grade III injuries represent 20% to 25% of collateral ligament injuries and occurred most commonly in football and soccer. LEVEL OF EVIDENCE: Level IV-retrospective case series.

Tears in the distal superficial medial collateral ligament: the wave sign and other associated MRI findings.

OBJECTIVE: To analyze the MRI characteristics of distal superficial medial collateral ligament (sMCL) tears and to identify features of tears displaced superficial to the pes anserinus (Stener-like lesion (SLL)). MATERIALS AND METHODS: Knee MRI examinations at four institutions were selected which showed tears of the sMCL located distal to the joint line. MRIs were evaluated for a SLL, a wavy contour to the sMCL, and the location of the proximal sMCL stump. Additional coexistent knee injuries were recorded. RESULTS: The study included 51 patients (mean age, 28 years [sd, 12]). A SLL was identified in 20 of 51 cases. The proximal stump margin was located significantly (p < 0.01) more distal and more medial with a SLL (mean = 33 mm [sd = 11 mm] and mean = 6.5 mm [sd = 2.5 mm], respectively), than without a SLL (mean = 19 mm [sd = 16 mm] and mean = 4.8 mm [sd = 2.4 mm], respectively). Medial compartment osseous injury was significantly (p < 0.05) more common with a SLL (75%) than without a SLL (42%). The frequency of concomitant injuries in the group (ACL tear, 82%; PCL tear, 22%; deep MCL tear, 61%; lateral compartment osseous injury, 94%) did not differ significantly between patients with and without a SLL. CONCLUSION: A distal sMCL tear should be considered when MRI depicts a wavy appearance of the sMCL. Distal sMCL tears have a frequent association with concomitant knee injuries, especially ACL tears and lateral femorotibial osseous injuries. A SLL is particularly important to recognize because of implications for treatment.

Anatomic medial complex reconstruction in serious medial knee instability results in excellent mid-term outcomes.

PURPOSE: To evaluate the mid-term outcomes of anatomic medial complex reconstruction in cases of serious medial knee instability. METHODS: Between 2010 and 2013, 23 patients who underwent anatomic medial complex reconstruction with a minimum 5-year follow-up were included. The Lysholm score, International Knee Documentation Committee subjective knee form (IKDC SKF), and Tegner activity scale scores were evaluated. Clinical and functional tests included valgus and sagittal stress tests, isokinetic muscle strength test, single leg hop for distance test (SLDT), and single leg vertical jump test (SLVT). RESULTS: The mean follow-up duration was 77.2 ± 10.8 months. At final follow-up, the Lysholm score improved from 49.7 ± 10.2 to 93.4 ± 12.4; the IKDC SKF score, from 46.2 ± 8.7 to 90.5 ± 13.9; and median Tegner activity, from 5 (4-7) to 7 (4-10) (P < 0.001). The mean side-to-side difference on valgus stress radiographs was significantly reduced to 1.2 ± 0.7 mm postoperatively compared to 8.5 ± 1.6 mm preoperatively (P < 0.001). The mean side-to-side differences on anterior and posterior stress radiographs were significantly improved in concomitant ACL and PCL reconstructions, respectively (P < 0.001). Preoperatively, 17 patients (73.9%) had anteromedial rotatory instability (AMRI), but none had AMRI at the last follow-up. The extensor peak torque and Limb Symmetry Index (LSI, %) improved from 128.2 ± 42.9 to 225 ± 39.4 N m/kg and from 61.4 ± 19.6 to 88.7 ± 21.7%, respectively (P < 0.001). The LSI (%) for SLDT and SLVT improved from 56.8 ± 19.5 to 87.3 ± 14.2% and from 68.1 ± 21.1 to 91.1 ± 12.8%, respectively (P < 0.001). No patient had a restricted range of movement. CONCLUSION: Although posteromedial corner injuries that need medial complex reconstruction are extremely rare, proper anatomic medial complex reconstruction of the medial collateral and posterior oblique ligaments achieved satisfactory clinical and functional outcomes at mid-term follow-up in cases with chronic symptomatic valgus and rotatory laxity. LEVEL OF EVIDENCE: Case series, level IV.