Congenital dislocation of the knee complicated with bilateral hip dislocation: a case report and literature review.

BACKGROUND: Congenital dislocation of the knee is characterised by excessive knee extension or dislocation and anterior subluxation of the proximal tibia, and this disease can occur independently or coexist with different systemic syndromes. Nevertheless, significant controversy surrounds treating this disease when combined with hip dislocation. This paper presents a case of a 4-month-old patient diagnosed with bilateral hip dislocation combined with this disease. The study discusses the pathophysiology, diagnosis, and treatment methods and reviews relevant literature. CASE PRESENTATION: We reported a case of a 4-month-old female infant with congenital dislocation of the right knee joint, which presented as flexion deformity since birth. Due to limitations in local medical conditions, she did not receive proper and effective diagnosis and treatment. Although the flexion deformity of her right knee joint partially improved without treatment, it did not fully recover to normal. When she was 4 months old, she came to our hospital for consultation, and we found that she also had congenital dislocation of both hip joints and atrial septal defect. We performed staged treatment for her, with the first stage involving surgical intervention and plaster orthosis for her congenital dislocation of the right knee joint, and the second stage involving closed reduction and plaster fixation orthosis for her congenital hip joint dislocation. Currently, the overall treatment outcome is satisfactory, and she is still under follow-up observation. CONCLUSIONS: Early initiation of treatment is generally advised, as nonsurgical methods prove satisfactory for mild cases. However, surgical intervention should be considered in cases with severe stiffness, unresponsive outcomes to conservative treatment, persistent deformities, or diagnoses and treatments occurring beyond the first month after birth.

Traumatic proximal tibiofibular fracture and dislocation.

BACKGROUND: Traumatic proximal tibiofibular fracture and dislocation (PTFD) have been rarely studied and are easily missed in clinical practice. PTFD is considered a marker of severely traumatized knees. The purpose of this study was to retrospectively analyze the incidence and impact of PTFD in traumatized knees with vascular injury. METHODS: Patients with knee trauma and vascular injury were included from January 2022 to October 2023. X-rays and CT scans of included patients were retrospectively analyzed to determine the presence of PTFD. Patients were further divided into PTFD group and non-PTFD group for further comparative analysis. RESULTS: A total of 27 patients (28 limbs) were included. Incidence of PTFD was 39.3% (11/28) in traumatic knee with vascular injury, including 8 anterolateral dislocations and 3 posteromedial dislocations. PTFD group had significantly more limbs with open injuries compared with non-PTFD group (10/11 VS 7/17, p<0.05). Amputation rate of PTFD group was as high as 40% (4/10), compared to 23.5% (4/17) in non-PTFD group. However, the difference between two groups was not statistically significant (p>0.05). CONCLUSIONS: PTFD was easily overlooked or missed. In traumatized knees with vascular injury, incidence of PTFD was high. The presence of PTFD might indicate severe knee trauma and the possibility of open injury. Although there was no significant difference compared with non-PTFD group, PTFD group had a relatively high amputation rate of 40%.

Magnetic resonance imaging quality in the context of a knee-spanning external fixator placed inside the MR bore: a literature review.

After emergent assessment of potentially limb-threatening injuries in knee dislocation or multi-ligament knee injury patients, magnetic resonance imaging is necessary to visualize ligamentous structures and plan for soft tissue repair. However, the application of a knee-spanning external fixator may introduce artifact and reduce overall image quality, which can limit the evaluation of soft tissue injury. As a result, the utility of MRI in the context of a knee-spanning external fixator has been called into question. Signal-to-noise ratio, contrast-to-noise ratio, and qualitative scales have been used to assess image quality of MRI in the context of a knee-spanning external fixator. Despite the potential for artifact, studies have demonstrated that useful diagnostic information may be obtained from MRI in the presence of an external fixator. This review examines the general principles of anatomical assessment, magnetic field strength, device composition and design, radiofrequency coil use, and MRI sequences and artifact reduction as they pertain to MRI in the presence of a knee-spanning external fixator.

No effect of dislocation status at arrival in emergency department on outcome of knee joint dislocations.

PURPOSE: Knee dislocation is a rare but severe injury of the lower extremities. The aim of this study was to report on the epidemiology, diagnostics and treatment of such injuries and to identify negative predictors of clinical outcomes. METHODS: This retrospective analysis included all knee dislocations treated at a Level I Trauma Centre in Germany between 2009 and 2021. Medical records were categorised, collected and analysed in a standardised manner. A follow-up visit 1 year after the injury focused on limitations in knee mobility. RESULTS: A total of 120 knee dislocations were included in the study. 29.3% of patients presented to the emergency department with a dislocated joint, and 17.5% (n = 21) had a neurovascular lesion. At follow-up 12 months after the injury, 65.8% of the patients reported limitations in the range of motion, and 11.7% (n = 14) reported severe limitations in daily activities. Site infections due to surgery occurred in 3.3% of patients. Increased body weight (r = 0.294; p < 0.001 and r = 0.259; p = 0.004), an increased body mass index above 25 kg/m2 (body mass index, r = 0.296; p < 0.001 and r = 0.264; p = 0.004) and deficits in peripheral perfusion as well as sensory and motor function (r = 0.231; p = 0.040 and r = -0.192; p = 0.036) were found to be negative predictive factors for clinical outcome. For posttraumatic neurovascular injury, lack of peripheral perfusion, insufficient sensory and motor function (r = -0.683; p < 0.0001), as well as a higher Schenck grade (r = 0.320; p = 0.037), were identified as independent risk factors. The status of dislocation at the site of the accident and on arrival at the emergency department had no impact on the outcome or neurovascular injury. CONCLUSION: Knee dislocation is a rare injury with a high rate of severe complications such as neurovascular lesions. In particular, the initial status of neurovascular structures and injury classification showed a relevant negative correlation with the posttraumatic status of nerves and vessels. In particular, patients with these characteristics need close monitoring to prevent negative long-term consequences. LEVEL OF EVIDENCE: Level III.

Long-term Outcomes of Surgically Treated Congenital Dislocation of the Knee.

BACKGROUND: Congenital dislocation of the knee (CDK) may be idiopathic or associated with another condition, such as Larsen syndrome or arthrogryposis. Surgical reduction of type-3 dislocation may require quadricepsplasty (QP) or femoral diaphyseal shortening (FS). Because it is unknown which treatment is more effective, we evaluated long-term outcomes using patient-reported questionnaires and gait analysis, comparing results by surgery type and underlying diagnosis. METHODS: Twelve patients (mean age, 19 mo) were treated surgically for CDK from 1985 to 2015 and studied 9 to 30 years postoperatively. Three participants had idiopathic CDK, 5 had Larsen syndrome, and 4 had arthrogryposis. Eleven knees underwent QP and 7 underwent FS. Participants were evaluated in our movement science laboratory and completed patient-reported outcome questionnaires. Data were compared with healthy, age-matched control values at the same visit. RESULTS: Surgically treated knees had less flexion during swing ( P <0.01), less overall motion ( P <0.01), greater coronal instability ( P <0.04), and slower gait ( P <0.01) compared with controls. QP knees had more instability in midstance ( P =0.03) and less flexion during gait compared with FS knees, less sagittal power generation than controls ( P <0.01), and trended toward lower scores on Knee Injury and Osteoarthritis Outcome and Lysholm Knee Questionnaires than FS patients did. The idiopathic group had the gait most similar to that of controls, followed by the Larsen syndrome group and then the arthrogryposis group. The idiopathic group also had a better UCLA Activity Score ( P =0.03) than the arthrogryposis group did. CONCLUSIONS: Surgical treatment of type-3 CDK will not likely restore normal knee function, suggesting teratologic joint abnormality. In this small series, FS produced better gait mechanics and patient-reported outcomes compared with QP. Not surprisingly, patients with idiopathic CDK had better outcomes than those with a syndromic diagnosis, likely related to having only a single joint affected. LEVEL OF EVIDENCE: Level III.

Knee dislocations and associated fractures: risk factors for surgical reduction.

INTRODUCTION: Dissociation of the knee joint, or knee dislocations (KD), can lead to severe complications, often resulting in multiligament injuries. A subset of these injuries are irreducible by closed reduction and require open reduction. Identifying KDs that necessitate surgical intervention is crucial for optimal outcomes. While previous studies have explored various risk factors, the influence of associated fractures is less understood. MATERIALS AND METHODS: We queried the Trauma Quality Improvement Program (TQIP) database from 2017 to 2021, for non-congenital closed knee dislocations requiring surgery. Demographic variables were collected, and ICD-10 codes were used to identify associated tibia, femur, acetabular, and fibula fractures. ICD-10 codes were also used to identify nerve injuries and vascular injuries. Multivariate logistic regression was used to assess factors influencing the need for surgical reduction (SR). RESULTS: A total of 1,467 patients with KDs were included in the study, of which 411 (28.0%) underwent open surgical reduction (SR) while 1,056 (72.0%) were treated with nonsurgical closed reduction (nSR). Factors associated with SR included concomitant tibia fracture (OR = 1.683, C.I: 1.255-2.256, p < 0.001) and fibula fracture (OR = 1.457, C.I: 1.056-2.011, p = 0.022). Vascular injury had lower odds of SR (OR = 0.455, C.I: 0.292-0.708, p < 0.001). CONCLUSION: Our study demonstrated that KDs presenting with concomitant tibia and/or fibula fractures are more likely to require SR. The difficulty posed to closed reduction may be due to the influence of these fracture patterns on surrounding soft tissue as well as the lack of a stable bone structure necessary for achieving proper reduction. Physicians should be aware of the potential risk of this fracture pattern when caring for patients with KDs.

Irreducible knee dislocation: improved clinical outcomes of open and arthroscopic surgical treatment. A systematic review of the literature.

PURPOSE: Irreducible knee dislocations (IKDs) are a rare rotatory category of knee dislocations (KDs) characterized by medial soft tissue entrapment that requires early surgical treatment. This systematic review underlines the need for prompt surgical reduction of IKDs, either open or arthroscopically. It describes the various surgical options for ligament management following knee reduction, and it investigates their respective functional outcome scores to assist orthopedic surgeons in adequately managing this rare but harmful KD. METHODS: A comprehensive search in four databases, PubMed, Scopus, Embase, and MEDLINE, was performed, and following the PRISMA guidelines, a systematic review was conducted. Strict inclusion and exclusion criteria were applied. Studies with LoE 5 were excluded, and the risk of bias was analyzed according to the ROBINS-I tool system. This systematic review was registered on PROSPERO. Descriptive statistical analysis was performed for all data extracted. RESULTS: Four studies were included in the qualitative analysis for a total of 49 patients enrolled. The dimple sign was present in most cases. The surgical reduction, either open or arthroscopically performed, appeared to be the only way to disengage the entrapped medial structures. After the reduction, torn ligaments were addressed in a single acute or a double-staged procedure with improved functional outcome scores and ROM. CONCLUSIONS: This systematic review underlines the importance of promptly reducing IKDs through a surgical procedure, either open or arthroscopically. Moreover, torn ligaments should be handled with either a single acute or a double-staged procedure, leading to improved outcomes. LEVEL OF EVIDENCE: IV.

Multiligament knee injuries. Ten years' experience at a public university, level I Trauma Center.

PURPOSE: To describe our institutional experience and results in the surgical management of multiligament knee injuries (MLKI). MATERIALS AND METHODS: Retrospective series of MLKI consecutively operated on at a single, level I Trauma Center. Data on patients' baseline characteristics, injuries, treatments, and outcomes were recorded up to one-year follow-up. Recorded outcomes included the Tegner-Lysholm Knee Scoring Scale (TLKSS), return to work, and patient satisfaction. RESULTS: MLKI incidence was 0.03% among 9897 orthopedic trauma admissions. Twenty-four patients of mean age 43.6 years were included in analysis. The mean Injury Severity Score was 12.6. Five patients presented with knee dislocations and six had fracture-dislocations, two of them open fractures. There was one popliteal artery injury requiring a bypass and four common peroneal nerve palsies. Staged ligamental reconstruction was performed in all cases. There were seven postoperative complications. The median TLKSS was 80 and, though patient satisfaction was high, and dissatisfaction was largely restricted to recreational activities (only 58.3% satisfied). Seventeen patients returned to their previous employment. CONCLUSIONS: We found a high aggregation of fracture-dislocations secondary to road traffic accidents. One in four patients experienced complications, particularly stiffness. Complications were more common in cases involving knee dislocation. Most patients had good functional results, but 25% were unable to return to their previous work, which demonstrates the long-lasting sequelae of this injury.

Frailty is a predictor of immediate postoperative complications following surgical management of knee dislocations.

PURPOSE: To assess the utility of frailty in predicting outcomes following surgical intervention for KDs. METHODS: The NIS database was queried for non-congenital knee dislocations from 2015 to 2019 that underwent ligament repair or surgical reduction. Patients were assigned frailty scores using the mFI-11, and outcomes were compared. Multivariate regression and ROC curve analysis were used to assess the independent association of obesity, frailty, VI, and age with adverse outcomes. RESULTS: A total of 3797 patients who underwent surgical management were included. Frailty was associated with extended LOS (OR 1.353, 95% CI 1.212-1.510, p < 0.001), adverse discharge (OR 1.716, 95% CI 1.515-1.946, p < 0.001), and complications (OR 1.449, 95% CI 1.352-1.553, p < 0.001). Severely frailty was associated with extended LOS (OR 1.838, 95% CI 1.611-2.097, p < 0.001), adverse discharge (OR 2.756, 95% CI 2.394-3.171, p < 0.001), and complications (OR 1.603, 95% CI 1.453-1.768, p < 0.001). Additionally, VI was a risk factor for extended LOS (OR 7.647 (6.442-9.076) p < 0.001), complications (OR 2.065 (1.810-2.341) p < 0.001), and adverse discharge (OR 1.825 (1.606-2.075), p < 0.001). Obesity was a risk factor for extended LOS (OR 1.599 (1.470-1.739), p < 0.001) and complications (OR 1.235 (1.108-1.377), p < 0.001). AUC analysis showed that frailty was the most accurate predictor of all outcomes when compared to VI, obesity, and age. CONCLUSIONS: Frailty is superior to age and obesity, and comparable to VI, at predicting adverse outcomes following surgical management of KDs. These findings suggest that frailty assessment might play a role in risk stratification and preoperative planning for KD patients that require surgical intervention.

Higher success rate observed in reconstruction techniques of acute posterolateral corner knee injuries as compared to repair: an updated systematic review.

PURPOSE: There remains controversy regarding the optimal surgical treatment for acute complete (grade III) posterolateral corner (PLC) injuries. The purpose of this article is to systematically review the contemporary literature regarding surgical options and subsequent outcomes of acute grade III PLC injuries. METHODS: A systematic review was performed using the following search terms: posterolateral corner knee, posterolateral knee, posterolateral instability, multi-ligament knee, and knee dislocation. Inclusion criteria consisted of studies with level I-IV evidence, reporting on human patients with acute grade III PLC injuries undergoing operative management within 4 weeks from injury, with subjective and/or objective outcomes (including varus stress examinations or varus stress radiographs) reported at a minimum 2-year follow-up. Two investigators independently performed the search by sequentially screening articles. Accepted definitions of varus stability on examination or stress radiographs and revision surgery were used to determine success and failure of treatment. RESULTS: A total of 12 studies, consisting of 288 patients were included. Ten studies reported primary repair, while reconstruction techniques were reported in seven studies. Overall, 43% (n = 125/288) of injuries involved the PLC, ACL and PCL. Staged reconstruction was reported in 25% (n = 3/12) of studies. The Lysholm score was the most commonly reported outcome measure. An overall failure rate of 12.4% (n = 35/282) was observed. Surgical failure was significantly higher in patients undergoing repair (21.9%; n = 21/96) compared to reconstruction (7.1%; n = 6/84) (p = 0.0058). Return to sport was greater in patients undergoing reconstruction (100%; n = 22/22) compared to repair (94%; n = 48/51) (n.s). The most common post-operative complication was arthrofibrosis requiring manipulation under anesthesia (8.7%; n = 25/288). A total of 3.8% (n = 11/288) of patients underwent revision PLC reconstruction. CONCLUSION: There remains substantial heterogeneity in the surgical techniques of acute, grade III PLC injuries with an overall failure rate of 12.4%. Failure rates were significantly lower, and return to sport rates higher in patients undergoing PLC reconstruction compared to repair. The most common postoperative complication was arthrofibrosis requiring manipulation under anesthesia. LEVEL OF EVIDENCE: Level IV.

Outside-in repair technique is effective in traumatic tears of the meniscus in active adults: a systematic review.

PURPOSE: Meniscal injuries are common. Outside-in meniscal repair is one of the techniques advocated for the management of traumatic meniscal tears. This systematic review investigated the outcomes of the outside-in repair technique for the management of traumatic tears of the menisci. The outcomes of interest were to investigate whether PROMs improved and to evaluate the rate of complications. METHODS: Following the 2020 PRISMA statement, in May 2023, PubMed, Web of Science, Google Scholar, and Embase were accessed with no time constraints. All the clinical investigations which reported data on meniscal repair using the outside-in technique were considered for inclusion. Only studies which reported data on acute traumatic meniscal tears in adults were considered. Only studies which reported a minimum of 24 months of follow-up were eligible. RESULTS: Data from 458 patients were extracted. 34% (155 of 458) were women. 65% (297 of 458) of tears involved the medial meniscus. The mean operative time was 52.9 ± 13.6 min. Patients returned to their normal activities at 4.8 ± 0.8 months. At a mean of 67-month follow-up, all PROMs of interest improved: Tegner scale (P = 0.003), Lysholm score (P < 0.0001), International Knee Documentation Committee (P < 0.0001). 5.9% (27 of 458) of repairs were considered failures. Four of 186 (2.2%) patients experienced a re-injury, and 5 of 458 (1.1%) patients required re-operation. CONCLUSION: Meniscal repair using the outside-in technique can be effectively performed to improve the quality of life and the activity level of patients with acute meniscal tears. LEVEL OF EVIDENCE: Level IV.

Subchondral insufficiency fracture is a predictive factor of osteoarthritis progression and conversion to arthroplasty in non-surgically treated medial meniscus root tear.

PURPOSE: To investigate the radiographic and clinical outcomes of non-surgical treatment for medial meniscus posterior root tear (MMPRT), and prognostic factors for osteoarthritis (OA) progression and clinical failure. METHODS: A prospectively collected database was retrospectively reviewed for patients who were diagnosed with acute medial meniscus posterior root tear (MMPRT) between 2013 and 2021 and treated non-surgically for more than 2 years. Patient demographic characteristics and clinical outcomes including pain numeric rating scale (NRS), International Knee Documentation Committee (IKDC) subjective score, Lysholm score, and Tegner activity scale were evaluated. For radiographic evaluation, knee radiographs were obtained to assess the angle of knee alignment and Kellgren-Lawrence (K-L) grade during the first and annually follow-up visits. Baseline magnetic resonance (MR) images were reviewed for the presence of medial meniscus extrusion, bone marrow edema, subchondral insufficiency fracture of medial femoral condyle, and cartilage lesion. The OA progression group was defined as patients who experienced a worsening of one or more grades in the K-L classification system. Prognostic factors were evaluated for OA progression and conversion to total knee arthroplasty (TKA). RESULTS: Ninety-four patients (90 female and 4 male) with a mean age of 67.0 ± 7.3 years (range, 53-83 years) were followed for a mean of 46.1 ± 22.1 months (range, 24.1-170.5). During the follow-up period, no significant differences in clinical scores were observed, and there were also no significant differences between the groups with and without OA progression. Overall, 12 patients (13%) underwent TKA at a mean of 20.7 ± 16.5 months (range, 8-69 months) and 34 patients (36%) demonstrated OA progression at a mean time of 24 ± 15 months (range, 12-62). The subchondral insufficiency fracture was a prognostic factor for OA progression (p = 0.045 for knee radiograph and p = 0.019 for MR) and conversion to TKA (RR, 4.08 [95% CI 1.23-13.57]; p = 0.022). CONCLUSIONS: Non-surgical treatment for acute medial meniscus posterior root tear did not result in any significant change in clinical outcomes from the initial to the final follow-up. The rate of conversion to arthroplasty was 13%, and the rate of osteoarthritis progression was 36%. Furthermore, subchondral insufficiency fracture was found to be a concomitant prognostic factor correlated with OA progression and conversion to arthroplasty. This information can provide insights for physicians when discussing treatment options with patients, particularly regarding the use of non-surgical treatment and may contribute as a source for future studies of medial meniscus posterior root tear. LEVEL OF EVIDENCE: IV.

Two-stage ligament reconstruction with remnant preservation as treatment of knee dislocation.

OBJECTIVE: The purpose of this study was to evaluate the clinical outcomes of two-stage reconstruction (peripheral reconstruction in phase I and central anterior cruciate ligament (ACL) / posterior cruciate ligament (PCL) reconstruction in phase II) with remnant preservation for patients with knee dislocation. METHODS: A total of 70 patients (10 IIIM, 17 IIIL, and 43 IV) with knee dislocation were randomly divided into the remnant-preserved group and the simple reconstruction group. Patients underwent two-stage reconstruction, including the reconstruction of collateral ligament in phase I and the reconstruction of ACL/PCL in phase II (12 weeks after phase I). Grafts were harvested from the semitendinosus and gracilis tendons from both lower limbs. After the surgery, the joint flexion and extension, bone tunnel and ligament healing, and joint stability were evaluated. RESULTS: After the surgery, the lateral stability recovered in all patients, and X-ray revealed a good position of bone tunnel. Follow-up was performed at 12 months postoperatively and ranged from 24 to 91 months. At the final follow-up, knee flexion angle, IKDC, Lysholm, and Tegner scores were all higher in both groups compared to the preoperative period. Notably, the remnant-preserved group showed superior results in these parameters compared to the simple reconstruction group. There was statistical significance between the two groups in terms of the Lachman test. CONCLUSION: The knee function was well recovered after two-stage ligament reconstruction with remnant preservation.

A Young Skier with Leg Pain.

BACKGROUND: Proximal tibiofibular joint (PTFJ) dislocation is a rare injury that can disrupt the proximal tibia-fibula joint. The abnormalities in knee x-ray imaging can be subtle and difficult to detect, requiring careful assessment. This rare cause of lateral knee pain requires a high level of suspicion for diagnosis. Treatment is closed reduction; unstable PTFJ dislocations often require surgical intervention. CASE REPORT: A 17-year-old young man presented to the emergency department (ED) with right lateral knee pain and difficulty walking after colliding with another skier 2 days prior. The examination showed right lateral ecchymosis and tenderness over the lateral proximal fibula. He remained neurovascularly intact with a full passive and active range of motion. X-ray studies were obtained. The patient was referred by his outpatient orthopedic surgeon after the initial knee x-ray study was concerning for PTFJ dislocation and unsuccessful reduction. In the ED, the patient underwent moderate sedation and successful orthopedic-guided reduction via medial force on the lateral fibular head, while hyper-flexing the knee and holding the foot dorsiflexed and everted. Post-reduction radiographs showed improved proximal tibiofibular alignment without fracture. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: PTFJ dislocation is a rare injury that can be missed easily and requires a high level of suspicion when presented with an acute traumatic knee pain. Closed reduction of PTFJ dislocation can be achieved in the ED and early identification can prevent long-term sequelae.

Clinical, functional, and patient-reported outcome of traumatic knee dislocations: a retrospective cohort study of 75 patients with 6.5-year follow-up.

INTRODUCTION: At present, limited knowledge regarding clinical, functional, and patient-reported outcomes at mid- and long-terms after surgical treatment of traumatic knee dislocations is available. This study aimed to investigate the mid-term recovery regarding clinical, functional, and patient-reported outcomes in patients following knee dislocation with associated multi-ligament injuries. MATERIALS AND METHODS: The study design was a cross-sectional cohort study. Data were collected by retrospective chart review, clinical examination, and interview of patients. All patients treated surgically following a knee dislocation between January 2000 and December 2011 were included. The surgical technique was up to the decision of the individual surgeon. The main outcome was the Lysholm knee score. Secondary outcomes consist of clinical knee examination, functional performance test, pain, and patient-reported outcome across several domains in function, sport, pain, and quality of life. RESULTS: Seventy-five patients (66.3%) accepted the invitation to participate. The mean age at the time of knee dislocation was 33.5 years, with a range of 16-65 years of age. The mean follow-up time was 78 months (R: 17-147). 75% of patient a Schenck's type 1 lesion and 23% a type 3. The median Lysholm knee score was 83 (R: 18-100). The mean KOOS for the five subscales were pain 84.5 (95% CI 80.5-88.5), symptoms 75.1 (95% CI 70.7-79.4), ADL 87.0 (95% CI 83.1-90.9), sport 59.9 (95% CI 53.3-66.4), and QOL 71.3 (95% CI 67.0-75.6). The mean Tegner activity level was 5.1 (95% CI 4.5-5.7). The median single assessment numeric evaluation (SANE) was 93 (R: 0-100). The pain intensity score for pain (VAS) during activity was reported with a mean of 2.7 (95% CI 2.1-3.3). The objective IKDC examination showed 76% of patients grouped by Grade A (normal knee function) or Grade B (nearly normal). CONCLUSION: With a mean follow-up of 6.5 years, combined repair and reconstruction surgery following a knee dislocation shows good to excellent patient-reported outcome and more than 75% of patients experiencing normal knee functioned evaluated by the IKDC score.

ACL reconstruction provides superior stability than ACL repair in patients with Schenck III and IV knee joint dislocations: first results of a 12 month follow-up study.

PURPOSE: Acute knee dislocation is a rare but devastating multi-ligamentous knee injury with only limited evidence-based surgical technique recommendations. The aim of this study was a comparison of two different anterior cruciate ligament (ACL) restoration techniques as part of an early total surgical care concept: (1) repair of ACL with additional internal bracing (ACLIB) compared to; (2) ACL reconstruction with autograft (ACLR). METHODS: Retrospective, clinical-study of patients with an acute type III or IV knee dislocation (according to Schenck classification), in which the ACL was treated with ACLIB or ACLR within 12 days. The PCL was sutured and internally braced in all cases. Medial and lateral complex injuries were repaired and additionally laterally augmented by an Arciero reconstruction. After a minimum 12 months follow-up different patient-reported outcome measurements (IKDC, Lysholm, VAS, Tegner Score) and instrumental stability assessment by Rolimeter -test and stress radiographs (Telos™) were analyzed. Groups were compared by t test with p < 0.05 considered significant. RESULTS: In total, 20 patients (5 IIIM, 5 IIIL and 10 IV) were included in this study with an average follow-up of 13.7 ± 2.6 months. There were significant differences in instrumental stability testing (side-to-side difference (SSD) of anterior tibial translation: ACLIB 2.7 ± 1.5 mm vs. ACLR 1.3 ± 1.3; p = 0.0339) and stress radiography (SSD ACL: ACLIB 3.4 ± 2.2 mm vs. ACLR 0.4 ± 2.7; p = 0.0249) between groups. ACLIB group showed greater ROM in terms of flexion (SSD Flexion: ACLIB 7.8 ± 9.9° vs. ACLR 16 ± 7.0°; p = 0.0466; Total Flexion overall 125.5 ± 11.8°). No clinically relevant differences in patient-reported outcome scores (Lysholm Score: ACLIB 82 ± 16.4 vs. ACLR 85 ± 10.4; IKDC subjective score: ACLIB 70.4 ± 17 vs. ACLR 76.6 ± 8.3) were determined. CONCLUSION: ACLR provides superior translational stability than ACLIB in terms of instrumental testing and stress radiography. Both techniques were equivalent with respect to PROMS and led to good and excellent clinical results. LEVEL OF EVIDENCE: Retrospective cohort study, III.

The diagnostic accuracy of MRI for evaluating the posterolateral corner in acute knee dislocation.

OBJECTIVE: To investigate the diagnostic performance of preoperative MRI in evaluating posterolateral corner (PLC) structures after acute knee dislocation (KD) and determine the correlation of MRI with operative findings for grading structure integrity. METHODS: Acute knee (femorotibial) dislocations between 2005 and 2020 with preoperative MRI and surgical posterolateral corner repair were identified from a single academic institution. From MRI, integrity was evaluated for PLC structures: lateral collateral ligament (LCL), popliteus tendon (PT), biceps femoris tendon (BFT), and ligamento-capsular complex (LCC). Frequency of injury to each structure and number of PLC structures torn in each case were tabulated. Diagnostic performance of MRI was determined using surgery as the reference standard. Correlation between MRI and surgery for each PLC structure was determined using kappa. RESULTS: Thirty-nine KD cases (19 right) in 39 patients (28 male) were included, with mean age of 33 years. Mechanism of injury was as follows: high energy 52%, low energy 38%, ultra-low energy 10%. LCL was most frequently torn, in 95% (37/39) of cases. Most commonly, three of four PLC structures were torn in 54% (21/39) of cases. Diagnostic accuracy of MRI was high for LCL 95%, BFT 87%, PT 82%, and LCC 92%. Correlation between MRI and surgical findings was variable: substantial for BFT, moderate for LCL and PT, and fair for LCC. CONCLUSION: MRI has high accuracy for detecting tears of posterolateral corner stabilizers in the setting of acute KD. However, for grading structure integrity, the correlation of MRI with surgical findings is variable, ranging from fair to substantial. KEY POINTS: • In acute knee dislocation, MRI has high diagnostic accuracy for detecting tears of posterolateral corner (PLC) structures. • Preoperative MRI should be considered by orthopedic surgeons when there is clinical concern for posterolateral corner instability following acute knee dislocation. • Although MRI is valuable in the preoperative investigation of knee dislocation, clinical assessment and intraoperative exploration may still be required for definitive diagnosis.

Proximal tibiofibular joint dislocation in young children: Is this the nursemaid's elbow of the lower extremity?

Anterolateral dislocation of the Proximal Tibiofibular Joint (PTFJ) is a rare injury of the knee commonly resulting from violent athletic injuries in adults. Reported here are examples of this injury in a 19 month old and a 4 year old following trivial mechanisms of injury. These cases raise the question of whether this injury may be an unrecognized cause of refusal to bear weight in children in this age group.

Open knee dislocation, triple intra-articular fractures and patellar tendon rupture: case report of a knee disaster treated with aggressive irrigation/debridement, early anatomic reduction and internal fixation.

BACKGROUND: Open knee fracture-dislocation is a rare orthopedic injury. However, the importance of its correct management could not be overstated. To the best of our knowledge, this is the fifth study reporting a case with simultaneous Hoffa fracture and knee dislocation and the 1st study describing a patient with open plateau fracture-dislocation accompanied with Hoffa fracture, patella fracture, and patellar tendon tear. In addition, this report is noticeable as our case had no gross ligament injury unlike frequent association of knee dislocation with knee collateral ligament damage. CASE PRESENTATION: In this study, we describe a 34-year-old motorcyclist referred to our center following a motor car accident. Further work-up revealed an open irreducible posterolateral knee dislocation, type 5 Hohl and Moore plateau fracture, lateral femoral condyle Hoffa's fracture, patellar fracture, and patellar tendon tear of his right knee. During an open reduction, it turned out that an entrapped lateral meniscus prevented the joint to be reduced by closed means. After applying a temporary external fixator, the patient was finally managed with open reduction and internal fixation. CONCLUSION: Irreducible knee dislocation needs further work up to rule out any interposed soft tissue into the joint. Aggressive irrigation/ debridement, early anatomic reduction, and internal fixation may help reduce open fracture complications including infection, non-union, and stiffness.

The accuracy of routine knee MR imaging in detection of acute neurovascular injury following multiligamentous knee injury.

OBJECTIVE: To assess the accuracy of routine knee MRI in detecting acute popliteal artery and/or common peroneal nerve (CPN) dysfunction following multiligamentous knee injury (MLKI), with correlation of MRI findings to clinical outcome. MATERIALS AND METHODS: Routine MRI knee examinations in 115 MLKI patients (54/115 with acute neurovascular injury, 61/115 without neurovascular injury) were retrospectively reviewed. Cases were classified by injury mechanism and ligamentous injuries sustained. MRI examinations were reviewed by two readers for vascular (arterial flow void, arterial calibre, intimal flap, perivascular hematoma) and CPN (intraneural T2-hyperintensity, calibre, discontinuity, perineural hematoma) injuries. Accuracy of routine knee MRI in the diagnosis of acute neurovascular injury and correlation of MRI findings to clinical outcome were evaluated. RESULTS: Patients included 86/115 males, mean age 33 years. The accuracy of MRI in diagnosis of acute CPN injury was 80.6%, 83.6% (readers 1 and 2): sensitivity (78%, 79.7%), specificity (80%, 86.7%), PPV (78%, 82.5%), and NPV (82.7%, 84.4%). Increased intraneural T2 signal showed a significant correlation to acute CPN dysfunction (p < 0.05). MRI was 75%, 69.8% (readers 1 and 2) accurate in detecting acute vascular injury: sensitivity (73.3%, 86.7%), specificity (75.2%, 67.3%), PPV (30.5%, 36.1%), and NPV (95%, 97.1%). No MRI features of vascular injury showed a statistical correlation with clinical outcome. Neurovascular complications were more common in ultra-low-energy injuries and KD-V3L pattern of ligament disruption. CONCLUSION: Routine MRI is of limited accuracy in assessing vascular complication, but higher accuracy in assessing CPN injury following MLKI. Increased intraneural T2 signal on conventional knee MR imaging shows statistically significant association with clinically documented acute CPN dysfunction following MLKI.