An examination from 1990 to 2019: investigating the burden of knee dislocation on a global scale.

Background: The literature on the disease burden of knee dislocation is lacking. The aim of the study is to systematically assess the global burden, trends, causes, and influencing factors of knee dislocation. Methods: The incidence and years lived with disability (YLDs) of knee dislocation were assessed globally, as well as at the regional and national levels from 1990 to 2019. Subsequent analyses focused on the age and gender distribution related to knee dislocation. An investigation into the main causes of knee dislocation followed. Finally, the Pearson correlation between age-standardized rates and social-demographic index (SDI) was calculated. Results: Although the age-standardized incidence and YLDs rate of knee dislocation decreased over the past 30 years, the incidence and YLDs number increased. The disease burden remained higher in males compared to females. Males and females showed different patterns of incidence rates in each age group, but their YLDs rates were similar. Over the past 30 years, the disease burden of knee dislocation increased in the older population while declining in the younger population. Falls had consistently emerged as the most important cause for both incidence and YLD rates. Additionally, a positive correlation between SDI and the disease burden of knee dislocation was found. Conclusion: The disease burden of knee dislocation remains heavy. It is essential to recognize the evolving epidemiology of knee dislocation. Utilizing data-driven assessments can assist in formulating public health policies and strategies to improve overall well-being.

Neurologic Assessment and Management of the Multiple Ligament Injured Knee: A Review and Synthesis of Current Evidence.

Knee dislocations are rare but devastating injuries that can often be associated with concomitant nerve injury, most often of the common peroneal nerve. Prompt diagnosis, investigation, and appropriate treatment are important in this subset of patients. This article provides an overview of relevant injury demographics, anatomy, diagnosis, and prognosis, and suggests a treatment algorithm for nerve injury associated with multiligament knee injury.

Multiple Ligament Injured Knee: Initial Assessment and Treatment.

The multiple ligament injured knee (knee dislocation) is oftentimes part of a multisystem injury complex that can include injuries not only to knee ligaments but also to blood vessels, skin, nerves, bones (fractures), head, and other organ system trauma. These additional injuries can affect surgical timing for knee ligament reconstruction and also affect the results of treatment. This article presents the author's approach and experience to the initial assessment and treatment of the multiple ligament injured (dislocated) knee.

Initial Assessment and Implications for Surgery: The Missed Diagnosis of Irreducible Knee Dislocation.

Irreducible knee dislocation is a rare but devastating orthopedic emergency. Limited discussion about its characteristics has been undertaken due to its low incidence. The purpose of this study was to present a series of irreducible dislocated knees and cumulatively reviewed all existing publications in this filed. A retrospective case series study was undertaken in patients with irreducible knee dislocation. Patients' data were carefully collected and presented. Historical cases of irreducible knee dislocation in published papers were reviewed, and their diagnosis, treatment, and prognosis were summarized. Six patients with six irreducible knee dislocations were enrolled with an average age of 51.2 ± 9.7 years. Patterns of injuries were classified into KD-III M (three cases), KD-IV (two cases), and KD-V (one case). Dimple sign was presented in all cases on both physical examination and MRI. All patients received single-stage arthrotomy together with cruciate ligament reconstruction acutely. In cumulative literature review, 34 papers with 45 irreducible knee dislocations were included. KD-III M was the most familiar type of ligamentous injury (75.0%). Dimple sign was recorded in 83.7% occasions and the most frequent two trapped structures were medial retinaculum (31.8%) and MCL (43.1%). Open reduction was conducted in all cases to reduce the knee, and the prognosis of 88.0% cases was considered to be acceptable after different staged surgery. The "dimple" sign is pathognomonic but not necessary for diagnosis of irreducible knee dislocations. The general consensus for treatment is immediate neurovascular status assessment and acute open reduction.

Assessment of clinical outcome of percutaneous needle quadriceps tenotomy in the treatment of congenital knee dislocation.

PURPOSE: Treatment of congenital knee dislocation (CDK) depends on the severity and flexibility of the deformity. Various modalities of treatment ranging from serial cast, open quadricepsplasty and minimally invasive quadricepsplasty have been described. We describe percutaneous needle quadriceps tenotomy for treatment of flexible CDK and present our result of retrospective case series. METHODS: This was a retrospective study of 12 patients (20 knees) with flexible CDK. Eight patients with bilateral and four with unilateral deformities. The mean age of intervention was 14.5 days (range, 4-55 days). None of the patients were syndromic. All procedures were done within eight weeks of age. The outcome was measured using knee evaluation score and complications in view of extensor lag, instability and knee flexion deformity. Ultrasound was performed to check for integrity of quadriceps mechanism. RESULTS: The mean pre-operative hyperextension was 50° (range, 30-70°). All patients were able to achieve >90° flexion intra-operatively. The mean knee flexion at walking age was 135° (range, 130-140°). Knee evaluation score showed good results in nine patients and fair result in three patients. There was no extensor lag, knee flexion deformity or infection. One patient of anterior instability had ACL aplasia which was documented on MRI. Ultrasound performed at walking age showed normal functioning of quadriceps mechanism. CONCLUSIONS: Percutaneous needle tenotomy of quadriceps is a effective, simple and safe procedure for flexible, non syndromic CDK presenting early. It avoids complications associated with the open surgical procedure and causes less extensor scarring. However its effectiveness in stiff/hyperlax variants associated with syndromes is yet to be determined.

Ultrasound assessment of medial meniscal extrusion: a validation study using MRI as reference standard.

OBJECTIVE. The purpose of this article is to validate both semiquantitative and quantitative ultrasound assessment of medial meniscal extrusion using MRI assessment as the reference standard. SUBJECTS AND METHODS. Ninety-three consecutive patients with chronic knee pain referred for knee MRI were evaluated by ultrasound and MRI on the same day. Two musculoskeletal radiologists assessed meniscal extrusion on ultrasound and MRI separately and independently and graded it semiquantitatively as follows: 0 (< 2 mm), 1 (≥ 2 mm and < 4 mm), and 2 (≥ 4 mm). Agreement between the ultrasound and MRI evaluations was determined using weighted kappa statistics. Intraclass correlation coefficients were used to evaluate agreement using the absolute values of extrusion (quantitative assessment). We further evaluated the diagnostic performance of ultrasound for the detection of medial meniscal extrusion using MRI as the reference standard. RESULTS. For semiquantitative grading, agreement between ultrasound and MRI was moderate for reader 1 (κ = 0.57) and substantial for reader 2 (κ = 0.64). Substantial agreement was found for both readers (intraclass correlation coefficients, 0.73 and 0.70) when comparing quantitative assessment of meniscal extrusion between ultrasound and MRI. Ultrasound showed excellent sensitivity (95% and 96% for each reader) and good specificity (82% and 70% for each reader) in the detection of meniscal extrusion. CONCLUSION. Ultrasound assessment of meniscal extrusion is reliable and can be used for both quantitative and semiquantitative assessment, exhibiting excellent diagnostic performance for the detection of meniscal extrusion compared with MRI.

Radiological assessment of irreducible posterolateral knee subluxation after dislocation due to interposition of the vastus medialis: a case report.

Knee dislocation is a serious and relatively uncommon traumatism that every emergency room is supposed to diagnose and treat rapidly. Most of the time these dislocations reduce spontaneously or with closed reduction. If a subluxation persists, an incarceration of soft tissue in the joint must be suspected. Irreducible knee subluxations after dislocation are rare entities better described in the orthopaedic than in the radiological literature. However, the initial radiological assessment is an important tool to obtain the correct diagnosis, to detect neurovascular complications, and to plan the most suitable treatment. In cases of delayed diagnosis, the functional prognosis of the joint and even the limb may be seriously compromised primarily because of vascular lesions. Thereby, vascular imaging is essential in cases of dislocation of the knee, and we will discuss the role of angiography and the more recent use of computed tomography angiography or magnetic resonance angiography. Our patient presented with an irreducible knee subluxation due to interposition of the vastus medialis, and we will review the classical clinical presentation and 'do not miss' imaging findings on conventional radiography, computed tomography angiography, and magnetic resonance imaging. Finally, we will also report the classical imaging pathway indicated in knee dislocation, with a special emphasis on the irreducible form.

Medial patellofemoral ligament reconstruction: a prospective outcome assessment of a large single centre series.

We report a prospective analysis of clinical outcome in patients treated with medial patellofemoral ligament (MPFL) reconstruction using an autologous semitendinosus graft. The technique includes superolateral portal arthroscopic assessment before and after graft placement to ensure correct graft tension and patellar tracking before fixation. Between October 2005 and October 2010, a total of 201 consecutive patients underwent 219 procedures. Follow-up is presented for 211 procedures in 193 patients with a mean age of 26 years (16 to 49), and mean follow-up of 16 months (6 to 42). Indications were atraumatic recurrent patellar dislocation in 141 patients, traumatic recurrent dislocation in 50, pain with subluxation in 14 and a single dislocation with persistent instability in six. There have been no recurrent dislocations/subluxations. There was a statistically significant improvement between available pre- and post-operative outcome scores for 193 patients (all p < 0.001). Female patients with a history of atraumatic recurrent dislocation and all patients with history of previous surgery had a significantly worse outcome (all p < 0.05). The indication for surgery, degree of dysplasia, associated patella alta, time from primary dislocation to surgery and evidence of associated cartilage damage at operation did not result in any significant difference in outcome. This series adds considerably to existing evidence that MPFL reconstruction is an effective surgical procedure for selected patients with patellofemoral instability.

Initial assessment of the acute and chronic multiple-ligament injured (dislocated) knee.

Multiple-ligament injured knees resulting from knee dislocations are uncommon but serious injuries. These injuries can present to the emergency room acutely or in clinic on a delayed basis, but regardless of the setting they require a complete and detailed assessment to evaluate the extent of the injury. Complicating the diagnosis of a knee dislocation is the fact that acute knee dislocations often spontaneously reduce or are reduced by paramedics in the field before evaluation by a physician. In most cases, pain in the knee, a large knee effusion, and swelling of the effected limb are the only signs and symptoms of a knee dislocation. Quick and accurate assessment of these injuries is required to determine the presence of any limb threatening arterial injuries. In this chapter, we present the complete assessment of acute and chronic multiple ligament knee injuries.

Posterior dislocation in total knee replacement: a price for deep flexion?

INTRODUCTION: Post-cam dislocation in TKA is a rare complication after posterior stabilized TKA. PURPOSE: Four cases of posterior dislocation of the tibia relative to the femur are described in one current posterior stabilized design. CONCLUSION: Specific design features in one contemporary high flexion TKA design contribute to high dislocation rates.

MR imaging of patellar instability: injury patterns and assessment of risk factors.

First-time patellar dislocation typically occurs with twisting knee motions, during which the medial ligamentous stabilizers rupture, and the patella strikes against the lateral femoral condyle. The typical injury pattern is a tear of the medial patellofemoral ligament (MPFL) and bone bruises of the patella and the lateral femoral condyle. Additionally, complex injuries to bone, cartilage, and ligaments may occur. The ensuing loss of medial restraint favors future patellar dislocations, especially if additional risk factors are present. Recurrent patellar dislocations usually occur in individuals with anatomic variants of the patellar stabilizers, such as trochlear dysplasia, patella alta, and lateralization of the tibial tuberosity. Magnetic resonance (MR) imaging is reliable in identifying risk factors for chronic patellar instability and in assessing knee joint damage associated with patellar dislocation. MR imaging can thus provide important information for individually tailored treatment. Patients with primary patellar dislocation without severe internal derangement who lack major risk factors can be treated conservatively. Patients with pronounced ligamentous tears or large osteochondral lesions require prompt surgery. In addition, surgical correction of anatomic variants will help reduce the potential for chronic instability. The most common procedures, in addition to MPFL reconstruction, include trochleoplasty, medialization of the tibial tuberosity, and medial capsular plication. For comprehensive assessment of patellar dislocation, a radiologist should be able to identify typical injury patterns, know standard methods to assess risk factors for patellar instability, and be familiar with surgical options.

Dislocation and bicruciate lesions of the knee: epidemiology and acute stage assessment in a prospective series.

INTRODUCTION: Knee dislocation and bicruciate lesions are rare. Assessments of results from retrospective series carry an insufficient level of evidence. A prospective multicenter study was therefore set up, under the auspices of the French Society of Orthopedic Surgery. MATERIAL AND METHODS: The inclusion period covered the whole of 2007. Clinical, imaging (dynamic X-ray and MRI) and vascular (angioscan and arteriography) assessment was performed systematically. In patients over the age of 60 years, ligament lesions were always managed non-surgically; in those under the age of 60 years, surgery was considered in the absence of associated vascular lesion or open dislocation and if there was frontal laxity exceeding 15 degrees or a posterior drawer test greater than 10mm. The posterior cruciate ligament (PCL) and peripheral ligament tears were repaired or reinforced under arthroscopy or by arthrotomy. The anterior cruciate ligament was never operated on. In all other cases, management was conservative. RESULTS: Sixty-seven knees were included (55 male, 11 female; mean age: 37 years). Fifteen patients (25.4%) had bicruciate lesion, and 44 (74.6%) knee dislocation. Mean trauma-to-reduction interval was 3 hrs 50 min. Only one of the nine cases of popliteal artery lesion exhibited discernible distal pulse wave. Only three of these patients underwent vascular surgical repair. Twelve knees (five bicruciate lesions, seven dislocations) had isolated common peroneal nerve damage. DISCUSSION: This prospective study detailed the epidemiology and treatment of the lesions encountered, with the option of PCL and peripheral ligament reconstruction. The results, however, still require long-term analysis.

Knee dislocations with vascular injury: outcomes in the Lower Extremity Assessment Project (LEAP) Study.

OBJECTIVES: The purpose of this study is to report the clinical and functional results of a cohort of patients with knee dislocations associated with vascular injury. METHODS: Patients with knee dislocation and associated vascular injury were prospectively assessed for outcome of severe lower extremity trauma during 2 years. The Sickness Impact Profile was used to assess the functional recovery of the patient. Surgeon and therapist assessments documented clinical metrics and treatment, including salvage or amputation, neurologic recovery, knee stability, and knee motion. RESULTS: Eighteen patients sustained a knee dislocation and an associated popliteal artery injury. Seven patients were found to have an additional vascular injury. All patients underwent repair of the vascular injury. At the time of final follow-up, 14 knees were successfully salvaged and four required amputation (1 below knee amputation, 2 through knee amputation, and 1 above knee amputation). Eighteen patients had at least a popliteal injury and underwent repair of the vascular injury. The patients with a limb-threatening knee dislocation that was successfully reconstructed had Sickness Impact Profile scores of 20.12 at 3 months, 13.18 at 6 months, 12.08 at 1 year, and 7.0 at 2 years after injury. CONCLUSIONS: Patients who sustain a limb-threatening knee dislocation have a moderate to high level of disability 2 years after injury. Nearly one in five patients who present to a Level I trauma center with a dysvascular limb associated with a knee dislocation will require amputation. Prolonged warm ischemia time was associated with a high rate of amputation. Patients who sustain vascular injuries associated with a knee dislocation need immediate transport to a trauma hospital, rapid assessment and diagnosis at presentation, and revascularization. Patients with these injuries can be effectively treated without angiography before surgery.