Irreducible posterolateral dislocation of the knee: a case report

Abstract

Irreducible posterolateral dislocations of the knee are rare lesions, generally caused by high-energy trauma inducing rotational stress and a posterior and lateral displacement of the tibia. In these conditions, the interposition of abundant soft tissue inside the enlarged medial joint space prevents spontaneous reduction or non-surgical treatment by manipulation of the dislocation. Surgical treatment is therefore compulsory. We report the clinical case of a woman who suffered a subluxation of the knee while jogging. The case we describe is of interest because it shows that even less severe knee dislocations, like this subluxation caused by a low-velocity sports trauma, may present in an irreducible form requiring open surgery. Clinicalinstrumental monitoring did not reveal any signs of vascular or nerve injury. Owing to the irreducibility of the lesion we were obliged to perform open surgery in order to free the joint from the interposed muscle tissue and repair medial capsule-ligament lesions. Repair of the damaged cruciate ligaments was deferred to a second stage, but ultimately rendered necessary by the persistence of joint instability and the need to address the patient's functional needs. In the literature, different one-and two-step surgical options, performed by arthroscopy or arthrotomy, are reported for such related problems. The Authors discuss these various options and examine and discuss their own decision taken during the surgical work-up of this case.Key Words: knee, posterolateral, dislocation, anterior cruciate ligament, injury. IntroductionDislocation of the knee is a rare orthopaedic emergency that requires appropriate monitoring and treatment. It has a low estimated annual incidence, accounting for less than 0.01% of trauma episodes, even if the true number of cases is unknown because many dislocations reduce spontaneously already at the site of the traumatic event (1). Most lesions of this kind are caused by high-velocity sports traumas (2), in which traumatic forces produce stress in the sagittal plane of the knee in the anteroposterior direction and in the frontal plane in varus-valgus angulation (3), inducing a rotational dislocation of the tibia in relation to the femoral condyles. This causes lesions of the ligament structures, also involving the popliteal artery in 20% of cases and the common peroneal or tibial nerve in 19% (4). In the literature, the role of non-surgical "closed" reduction is emphasized (5), while surgical treatment should be reserved for irreducible cases or those in which vesselnerve complications arise or there are signs of immediate joint instability (6). Case reportA healthy 51-year-old woman suffered a traumatic sprain of her left knee when she fell while jogging. Unable to stand or walk, she was immediately transfer-

One-Stage Arthroscopic Reduction Combined with Multiligament Reconstruction or Repair for Irreducible Posterolateral Knee Dislocation: A Retrospective Case Series with Minimum 2-Year Follow-Up

“…[1][2][3] This injury typically occurs when a valgus force is applied to a flexed knee with external rotation of the tibia. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] The medial femoral condyle button-holes through the torn medial capsuloligament complex as a flexed knee is forced into severe valgus. As the deforming force dissipates, the knee partially reduces.…”

“…Over the past two decades, open reduction has been the most widely used method for the management of irreducible posterolateral knee dislocation. [4][5][6][7][8][9][10][11][12][13][14] Although this method is simple and reportedly yields satisfactory clinical outcomes, it can cause further damage to the torn medial structures and could result in fluid extravasation into the soft tissues around the joint during cruciate ligament reconstruction.…”

“…31 No. 10/2018divided into three categories:(1) open reduction combined with ligament reconstruction or repair, (2) arthroscopic reduction combined with ligament reconstruction or repair, and(3)total knee replacement, which is more suitable for elderly patients with advanced joint osteoarthritis [4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Kilicogluet al reported a patient who underwent a onestage procedure of open reduction combined with ACL/PCL reconstruction and simultaneous MCL repair for irreducible posterolateral knee dislocation.…”

Traumatic Dislocation of Three Major Joints in the Lower Limb: Management and Outcome

“…X-ray: LL view the surgical repair and then bone stabilization (14) The second factor is the association between knee dislocation and open fractures (15). The third factor is represented by irreducible dislocation of the knee (16,17). Knee dislocation is usually treated in a cast or brace for weeks.…”

Irreducible Posterolateral Fracture Dislocation of the Knee in an Elderly Patient Treated with Rotating Hinge Total Knee Replacement

“…Irreducible posterolateral knee dislocation is a rare but well-documented entity. [3][4][5][6][7][8]12,14,[24][25][26][27][28][29] Surgical repair or reconstruction of soft tissue and ligament at the time of open reduction can be performed, but treatment algorithm is variable in the case report. Malik et al 30 have recently proposed an algorithm for the management of irreducible posterolateral knee dislocation without vascular injury.…”