Posteromedial Corner Injuries Research Articles

Posteromedial Corner Injuries of the Knee: Imaging Findings.

The posteromedial corner (PMC) of the knee is an anatomical region formed by ligamentous structures (medial collateral ligament, posterior oblique ligament, oblique popliteal ligament), the semimembranosus tendon and its expansions, the posteromedial joint capsule, and the posterior horn of the medial meniscus. Injuries to the structures of the PMC frequently occur in acute knee trauma in association with other ligamentous or meniscal tears. The correct assessment of PMC injuries is crucial because the deficiency of these supporting structures can lead to anteromedial rotation instability or the failure of cruciate ligaments grafts. This article reviews the anatomy and biomechanics of the PMC to aid radiologists in identifying injuries potentially involving PMC components.

MR evaluation of the posteromedial corner of the knee: association of posterior horn medial meniscus tear with posterior oblique ligament and distal semi-membranosus tendon tear.

To assess if posterior oblique ligament and distal semi-membranosus tendon tears are associated with posterior horn medial meniscus tears on MRI. From January 1, 2018 to December 31, 2019, 56 patients who met the inclusion criteria were enrolled in this study. Of the 56 patients, 43 patients who had a posterior horn of medial meniscus tear were included in the study group. A control group of 13 individuals was formed for comparison. Two radiologists reviewed the MR images and recorded the presence and grades of posterior oblique ligament and distal semi-membranosus tendon tears. We used the independent t-test and one-way ANOVA to compare the tear grades. Interobserver agreement was analyzed using a Cohen's κ coefficient (κ value) for categorical variables. The mean grades for the posterior oblique ligament and distal semi-membranosus tendon tears were significantly higher in the study group (all, p < 0.001). Interobserver agreement between the two readers was substantial in assessing the grade of posterior oblique ligament tear (κ = 0.653±0.087) and almost perfect in assessing the grade of distal semi-membranosus tendon tear (κ = 0.876±0.060). Posterior oblique ligament and distal semi-membranosus tendon tears are significantly associated with posterior horn of medial meniscus tear and medial meniscus posterior root tears, and the peel-back mechanism could be related to this association. Presenting this paper could adjust radiologist search patterns and potentially help orthopedists with management and pre-surgical planning for the posteromedial corner injury of the knee.

Surgical Principles for Medial and Posteromedial Knee Injuries

Injuries to the medial side of the knee are among the most common knee ligament injuries. Treatment of these injuries require a thorough clinical workup and an intricate knowledge of the anatomy and biomechanics involving this region of the knee. Low grade injuries and isolated injuries to the medial collateral ligament (MCL) are treated nonoperatively with bracing and functional rehabilitation. Surgical treatment is recommended for high grade (Grade III) posteromedial corner injuries, distal MCL tears, including Stener lesions, knee dislocations and multiple ligament knee injuries involving the posterolateral corner (PLC) because of high risk of residual instability if treated non-operatively. When indicated, surgical treatment should be performed in the acute phase followed by early protected range of motion and functional rehabilitation. Preoperative planning should include stress radiographs and MRI. Important considerations for surgical technique include avoiding graft tunnel convergence in the setting of multiple ligament reconstruction and anatomic placement of the tunnels to recreate the native kinematics of the medial compartment. Postoperative rehabilitation focusing on quadriceps activation and protected range of motion is recommended beginning postoperative day one to minimize the risk of arthrofibrosis. Anatomic reconstruction of the superficial medial collateral ligament and posterior oblique ligament have been shown to produce good subjective and objective patient outcomes. Further level one studies are recommended to reinforce these findings.

Anatomic medial knee reconstruction restores stability and function at minimum 2 years follow-up.

Chronic grade 3 tears of the medial collateral ligament and posterior oblique ligament may result in valgus laxity and anteromedial rotational instability after an isolated or multiligament injury. The purpose of this study was to prospectively analyze the restoration of physiologic medial laxity as assessed on stress radiography and patient reported subjective functional outcomes in patients who undergo an anatomic medial knee reconstruction. This was a prospective study which included patients with chronic (> 6weeks old) posteromedial corner injury with or without other ligament and meniscus lesions. Pre- and post-operative valgus stress radiographs were performed in 20° knee flexion and functional outcomewas recorded as per the International Knee Documentation Committee (IKDC) and Lysholm scores. All patients underwent anatomic medial reconstruction with two femoral and two tibial sockets using ipsilateral hamstring tendon autograft. Simultaneous ligament and meniscus surgery was performed as per the associated injury pattern. All patients were followed up for a minimum of 24months post-surgery. Thirty-four patients (23 males, 11 females) were enrolled in the study and all were available till final follow-up of mean 49.7 ± 14.9months. The mean age was 30.6 ± 7.9 (18-52years). Two patients had isolated medial sided lesions and 23 had associated ligament injuries. The mean follow up was 49.7 (24-72) months. The mean IKDC score improved from 58 ± 8.3 to 78.2 ± 9.5 (p < 0.001). Post-operatively there were 15 excellent, 11 good and 8 fair outcomes on Lysholm score. The mean pre-operative valgus side-to-side opening improved from 7.5 ± 2.5mm to 1.2 ± 0.7mm on stress radiography (p < 0.001). Anatomic reconstruction of the superficial medial collateral and posterior oblique ligaments restore stability in a consistent manner cases of chronic grade 3 instability. The objective functional results, subjective outcomes and measures of static medial stability are satisfactory in the short term. IV.

The posteromedial corner of the knee: an international expert consensus statement on diagnosis, classification, treatment, and rehabilitation.

PurposeTo establish recommendations for diagnosis, classification, treatment, and rehabilitation of posteromedial corner (PMC) knee injuries using a modified Delphi technique.MethodsA list of statements concerning the diagnosis, classification, treatment and rehabilitation of PMC injuries was created by a working group of four individuals. Using a modified Delphi technique, a group of 35 surgeons with expertise in PMC injuries was surveyed, on three occasions, to establish consensus on the inclusion or exclusion of each statement. Experts were encouraged to propose further suggestions or modifications following each round. Pre-defined criteria were used to refine item lists after each survey. The final document included statements reaching consensus in round three.ResultsThirty-five experts had a 100% response rate for all three rounds. A total of 53 items achieved over 75% consensus. The overall rate of consensus was 82.8%. Statements pertaining to PMC reconstruction and those regarding the treatment of combined cruciate and PMC injuries reached 100% consensus. Consensus was reached for 85.7% of the statements on anatomy of the PMC, 90% for those relating to diagnosis, 70% relating to classification, 64.3% relating to the treatment of isolated PMC injuries, and 83.3% relating to rehabilitation after PMC reconstruction.ConclusionA modified Delphi technique was applied to generate an expert consensus statement concerning the diagnosis, classification, treatment, and rehabilitation practices for PMC injuries of the knee with high levels of expert agreement. Though the majority of statements pertaining to anatomy, diagnosis, and rehabilitation reached consensus, there remains inconsistency as to the optimal approach to treating isolated PMC injuries. Additionally, there is a need for improved PMC injury classification.Level of evidenceLevel V.

Effect of posteromedial corner injury on stability and second-look arthroscopic findings after posterior cruciate ligament reconstruction using allograft

PurposeThe purpose of our study was to assess effect of posteromedial corner(PMC) injury on clinical outcomes and second-look arthroscopic findings after posterior cruciate ligament(PCL) reconstruction using Achilles tendon allograft. MethodsA total of 51 patients who underwent arthroscopic PCL reconstruction for PCL rupture and second-look arthroscopy were retrospectively enrolled in our study from 2009 to 2019. The subjects were divided into two groups: PMC intact group included 31 patients; and PMC injured group included 18 patients. At least 1 years follow-up, clinical outcomes and arthroscopic findings including synovial coverage, tension were evaluated. ResultsArthroscopic findings including the synovial coverages, tension showed significantly better at PMC intact group. (p < 0.005) but, no statistic difference was seen in clinical outcomes including KT-2000 value, last Lysholm score, posterior drawer test. ConclusionFor PCL ruptures with PMC injuries, treatment for PMC should be considered due to graft status. Level of studyIV.

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.

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

To evaluate the mid-term outcomes of anatomic medial complex reconstruction in cases of serious medial knee instability. 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). The mean follow-up duration was 77.2 ± 10.8months. 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 ± 0.7mm postoperatively compared to 8.5 ± 1.6mm 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 ± 39.4Nm/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. 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. Case series, level IV.

Posteromedial Corner Knee Injuries: Diagnosis, Management, and Outcomes: A Critical Analysis Review.

* The posteromedial corner of the knee comprises the superficial medial collateral ligament (MCL), deep MCL, posterior oblique ligament, oblique popliteal ligament, and posterior horn of the medial meniscus. The main medial knee structure is the superficial MCL.* Injuries to the medial knee are the most common knee ligament injuries. A comprehensive history and physical examination are key to the diagnosis of a posteromedial corner injury. Patients often present with swelling and pain over the medial joint line after an injury involving a valgus and external rotation force. The valgus stress and anteromedial drawer tests can aid the clinician in deciphering whether an isolated medial structure was injured or if a complete posteromedial corner injury is likely.* Valgus stress radiographs can be utilized to quantify the amount of medial joint gapping. A side-to-side difference in gapping of 3.2 mm is consistent with an isolated superficial MCL tear, and a side-to-side difference of ≥9.8 mm is consistent with a complete posteromedial corner injury. Magnetic resonance imaging is also a useful tool in the detection of medial-sided injuries and has been reported to have an 87% accuracy.* Although a large number of medial knee injuries can be treated nonoperatively, complete posteromedial corner injuries may require surgical treatment to restore joint stability and biomechanics. There is heterogeneity between techniques with regard to the type of graft, the tibial and femoral tunnel position, and the tensioning protocol. Anatomic techniques have been reported to better restore knee kinematics and function.

The Posteromedial Corner of the Knee: Anatomy, Pathology, and Management Strategies.

The posteromedial corner of the knee encompasses five medial structures posterior to the medial collateral ligament. With modern MRI systems, these structures are readily identified and can be appreciated in the context of multiligamentous knee injuries. It is recognized that anteromedial rotatory instability results from an injury that involves both the medial collateral ligament and the posterior oblique ligament. Like posterolateral corner injuries, untreated or concurrent posteromedial corner injuries resulting in rotatory instability place additional strain on anterior and posterior cruciate ligament reconstructions, which can ultimately contribute to graft failure and poor clinical outcomes. Various options exist for posteromedial corner reconstruction, with early results indicating that anatomic reconstruction can restore valgus stability and improve patient function. A thorough understanding of the anatomy, physical examination findings, and imaging characteristics will aid the physician in the management of these injuries.

Posteromedial Corner Reconstruction

Objective:Report the experience, after 1-year follow-up, of 30 patients who underwent anatomical knee reconstruction of posteromedial corner (PMC) injuries, using La Prade´s Technique.Methods:Retrospective cohort study of 30 consecutive patients with PMC injuries operated between November 2010 and May 2014 by the same surgical team. Inclusion criteria: patients with clinical presentation and images (stress radiographs and MRI) compatible with PMC injury, who maintained a grade III chronic instability in spite of at least 3 months of orthopedic treatment, who were reconstructed using La Prade’s anatomical technique, and completed at least 12 months of follow-up. Exclusion criteria: discordance between clinical and image studies, grade I or II medial instability, and surgery performed through a different technique. Data was collected by reviewing the electronic files and images. Functional scores (IKDC and Lysholm) were applied and registered in the preoperative evaluation, and then 6 and 12 months after surgery.Results:Thirty patients (28 men and 2 women) met the inclusion criteria. Mean age was 43 years (24-69). The vast majority (28 patients) had a high-energy mechanism of injury. Twenty patients were diagnosed in the acute setting, while 10 had a delayed diagnosis after poor results of concomitant ligament reconstructions. With the exception of 2 patients, who presented with isolated PMC injury, the majority had associated injuries as detailed: 11 cases had PMC + anterior cruciate ligament (ACL) injury, 3 patients had PMC + posterior cruciate ligament (PCL) injury, 3 patients had PMC + meniscal tears, 9 patients had PMC + ACL + PCL injuries, and there were 2 cases of PMC + ACL + PCL + lateral collateral ligament injuries. Mean time for PMC reconstruction surgery was 5 months (range 2-32). Lysholm and IKDC scores were 18,2 (2-69) and 24,3 (9,2-52,9) respectively in the preoperative setting, improving to 76,7 (44-94) and 70,7 (36,8-95,4) after 1-year follow-up. At the end of follow-up, average ROM was 113º (90-140) the majority (24 patients) had type A IKDC stability, and the remaining 6 patients type D IKDC stability.Conclusion:Acceptable results were achieved following reconstruction of PMC injuries in patients with chronic posteromedial knee instability. Improvement in stability and functional scores were observed in all the patients of this cohort after surgery.

Posterior cruciate ligament reconstruction with �all-inside� technique: a technical note

posterior cruciate ligament (PCL) injuries are an increasingly recognized cause of knee instability in the practice of orthopaedic surgery and sports medicine. Clinical interest in these injuries has been increasing over the last several decades as knowledge and understanding of the biomechanical consequences and surgical reconstruction options have progressed. These injuries can be extremely challenging for the treating physician as substantial controversy exists regarding the optimal management of this problem. There has also been increasing interest and recognition of the importance of secondary stabilizing structures, including the posterolateral and posteromedial corner injuries as well as the issues with malalignment that must also be addressed at the time of PCL surgery to optimize results. Thanks to the continuous research for a correct anatomical placement and new systems of fixation, we can now perform the tibial and femoral bone tunnel more easily and safely by retrograde out-in approach with a special "drill-pin". this technique provides a graduated precise execution of the tunnels. New methods were also developed to determine the so-called "second-generation cortical suspensory fixations" that have the feature of being "Adjustable": shortens implant by pulling on strands to allow cinching graft passing and tensioning button to regulate their length after fixation and then to create tension in the new graft, once introduced into the joint.

Posteromedial Corner Injury in Knee Dislocations

Surgeons are often faced with very limited data available to make informed decisions regarding the appropriate treatment of patients with posteromedial corner (PMC) injuries of the knee. This study compared the outcomes of surgical repair versus reconstruction in knee dislocation patients who have sustained injury to the PMC of the knee. Senior author treated 113 consecutive knee dislocations with 115 PMC injuries over 7 years. A total of 71 knee dislocation patients with 73 PMC tears qualified for the study and were followed for a mean of 43 months. Patients who had a PMC repair were assigned to treatment Group A. Group B included patients who had autograft reconstruction of the PMC. Patients who had an allograft PMC were assigned to Group C. A total of 25 patients had a repair, with 5 failures (20%), whereas 48 patients had reconstruction of the PMC with 2 failures (4%). There was a significant difference between the failure rate of PMC repairs and PMC reconstructions. Reconstruction of the PMC using a technique that reestablishes the critical triangle of the medial collateral ligament, the posterior oblique ligament, and the semitendinosus yielded better stability than repair in patients with a knee dislocation that included PMC instability.

Management of Medial-Sided Knee Injuries, Part 2

Injury to the posteromedial corner (PMC) of the knee differs anatomically and biomechanically from isolated injury to the medial collateral ligament. Newer anatomic and biomechanical studies are refining the field’s understanding of the medial side of the knee, as well as its role in multiple ligament injuries. Valgus instability places additional strain on a reconstructed anterior or posterior cruciate ligament, which can contribute to late graft failure. Injuries to the PMC may not heal without surgical repair or reconstruction, particularly when part of a multiple-ligament injury. Identification of PMC injury before cruciate reconstruction is important so that appropriate repair or reconstruction of the PMC and medial collateral ligament can be undertaken at the same time. This article reviews the relevant literature on the PMC, discusses reasons for selective operative management, and illustrates reconstructive strategies for PMC injuries occurring as part of a medial-sided or multiligament injury to the knee.

Medial and Posteromedial Instability of the Knee: Evaluation, Treatment, and Results

Medial-sided knee ligament injuries are complex and require a thorough understanding of the anatomy and the scope of injury to successfully treat. Patients with isolated medical collateral ligament (MCL) tears can normally be treated with bracing followed by physical therapy with outstanding results. Patients with isolated Grade III injuries to the MCL are controversial. A reason for the disparity in results reported may be due to the fact that many (if not most) Grade III MCL tears have associated injuries to the anterior cruciate ligament and/or posteromedial corner injury. Patients with combination injuries should be treated surgically with repair or reconstruction in most cases. Either allograft or autograft reconstructions of both the MCL and posteromedial corner can be successful. Successful elimination of anteromedial rotary instability is the key to successfully treating posteromedial corner injuries.

Injury patterns to the posteromedial corner of the knee in high-grade multiligament knee injuries: a MRI study

Injury patterns to the posteromedial corner of the knee have not been previously studied in the context of multiligament knee injuries. We performed a retrospective magnetic resonance imaging and clinical review of a consecutive series of 27 dislocatable knees presenting to a single level-one trauma center from 2005 to 2008. Post-injury magnetic resonance imaging studies were reviewed by two fellowship-trained musculoskeletal radiologists to assess injury patterns to the posteromedial corner. In our series, injury to at least one structure within the posteromedial corner was observed in 81% (22/27) of cases while injury to the superficial medial collateral ligament alone was seen in 63% (17/27) of cases. Furthermore, injuries to the posterior horn of the medial meniscus were associated with a tear of the meniscotibial ligaments in all cases and with a tear of the posterior oblique ligament in 67% of cases. All patients with grade III laxity (>10 mm medial opening) under an examination under anesthesia had a complete tear of the posterior oblique ligament and meniscotibial ligament in addition to a medial collateral ligament injury. Injury to the semimembranosus attachment alone was not associated with clinically significant laxity under an examination under anesthesia. Our findings demonstrate that injuries to the posteromedial corner are common in the setting of traumatic knee dislocations. Interestingly, high-grade medial instability during an examination under anesthesia and injury to the posterior horn of the medial meniscus may be important indicators for further posteromedial corner injury.

Single Soft Tissue Graft Reconstruction of the Fibular Collateral Ligament and Posterolateral Corner (SS-48)

We report outcomes of a new technique utilizing a single soft tissue graft for FCL and posterolateral corner reconstruction, followed by a posterolateral capsular shift. Our technique takes into account the three main static posterolateral corner stabilizers (popliteofibular ligament, fibular collateral ligament, and posterolateral capsule). 19 knees in 19 patients were identified. Average follow-up was 19 months (range 12-29 months). Mean IKDC subjective score was 67, mean Lysholm score was 76. Complications included manipulation in two patients, and superficial wound infection requiring antibiotics in one patient. Only one patient has required revision reconstruction. Our series demonstrated satisfactory clinical and functional results. The purpose of this study is to present the functional and clinical outcomes of a consecutive series of patients who underwent fibular collateral ligament (FCL) and posterolateral corner reconstruction (PLC) utilizing a single soft tissue allograft construct. All patients were identified through our prospective sports medicine database. Only patients who had undergone FCL and PLC reconstruction (as opposed to repair) were included. All patients underwent identical surgical technique and followed a standard postoperative rehabilitation protocol. Functional and clinical outcomes were assessed utilizing physical exam, Lysholm scores, and International Knee Documentation Committee (IKDC) subjective scores. Between August 2004 and September 2006, 19 knees in 19 patients were identified. There were 16 males and 3 females. Average age was 28 years (range 20 to 61 years). All patients were followed for a minimum of 1 year with a mean clinical follow-up of 19 months (range 12-29 months). All patients sustained injuries to other ligaments in addition to the posterolateral corner. In total, there were 16 anterior cruciate ligament injuries, 13 posterior cruciate ligament injuries, and 4 posteromedial corner injuries which required reconstruction. Mean IKDC subjective score was 67 (range 24-99), and mean Lysholm score was 76 (range 38-99). Average knee range of motion was 104 degrees (range 80-150 degrees). Complications included stiffness requiring manipulation in two patients, and superficial wound infection requiring antibiotics in one patient. One posterolateral corner reconstruction has required revision to date. Numerous posterolateral corner techniques have been reported in the literature with varying degrees of success. We describe a technique that takes into account the three main static posterolateral corner stabilizers (popliteofibular ligament, fibular collateral ligament, and posterolateral capsule) which has not beenpreviously reported. Our series demonstrated satisfactory clinical and functional outcomes.

Posteromedial corner injuries of the knee

Posteromedial corner injuries of the knee

Double-Bundle Transtibial Posterior Cruciate Ligament Reconstruction With a Tendon–Patellar Bone–Semitendinosus Tendon Autograft: Clinical Results With a Minimum of 2 Years’ Follow-Up

The purpose of this study was to evaluate the clinical and subjective outcomes after arthroscopic-assisted double-bundle posterior cruciate ligament (PCL) reconstruction. A series of 15 patients with grade III isolated chronic PCL tears underwent double-bundle PCL reconstruction. Of these patients, 8 (53%) had simultaneous fractures. The mean time from accident to surgery was 10.8 months (range, 8 to 15 months). The mean age at the time of surgery was 28.2 years (range, 17 to 43 years). All of the patients reported knee insecurity during activities of daily living or light sporting activities, with associated anterior knee pain in 5 patients. Preoperatively, posterolateral or posteromedial corner injuries were ruled out through accurate clinical examination. The knees were assessed before surgery and at a mean follow-up of 3.2 years (range, 2 to 5 years) with a physical examination, 4 different rating scales, and stress radiographs obtained with a Telos device (Telos, Marburg, Germany). Postoperative physical examination revealed a reduction of the posterior drawer and tibial step-off in all cases, although the posterior laxity was not completely normalized. Nevertheless, the patients were subjectively better after surgery. The subjective International Knee Documentation Committee score was significantly ameliorated. With regard to the objective International Knee Documentation Committee score, 6 knees (40%) were graded as abnormal because of posterior displacement of 6 mm or greater on follow-up stress radiographs with the Telos device. On the Lysholm knee scoring scale, the score was excellent in 13% of patients and good in 87%. The mean score on the Hospital for Special Surgery knee ligament rating scale was 85.8. The Tegner activity score showed an amelioration after surgery, but no patient resumed his or her preinjury level of activities. The postoperative stress radiographs revealed an improvement in posterior instability of 50% or more in all but 3 knees (20%). Our technique of double-bundle PCL reconstruction produced a significant reduction in knee symptoms and allowed the patients to return to moderate or strenuous activity, although the posterior tibial translation was not completely normalized and our results appear to be no better than the results of single-bundle PCL reconstruction. Level IV, therapeutic case series.

Physical Examination and Imaging of the Medial Collateral Ligament and Posteromedial Corner of the Knee

The medial side is one of the most commonly injured areas of the knee. The anatomy, diagnosis, and treatment of medial collateral ligament and posteromedial corner (PMC) injuries can be challenging. Understanding the mechanism of injury and performing a thorough physical examination and radiographic evaluation is essential. Frequently, there are concomitant meniscal and other ligament injuries associated with medial-side injuries. Correct identification of all injured structures is important, as missed diagnoses can lead to significant disability. Unrecognized PMC injuries have been implicated in anteromedial rotary instability and failed anterior cruciate ligament reconstructions. Valgus stress testing is the cornerstone for the identification of medial-side knee injuries. Coronal sequences from magnetic resonance imaging are the most useful tool to view the medial collateral ligament and posteromedial structures. Stress x-rays and ultrasound may also be helpful. Thorough physical examination and imaging of injuries to the PMC should dictate the appropriate treatment for optimal results.