The posterior cruciate ligament and rotatory knee instability. An experimental study

The importance of the posterior cruciate ligament in relation to valgus-varus and axial rotatory stability in the knee joint was investigated. Mobility patterns were drawn from 20 osteoligamentous preparations after successive transection of the posterior cruciate ligament (PCL), the medial and lateral collateral ligaments, and the posterior joint capsule. The knee joint remained grossly stable after isolated transection of the PCL, and further cutting of either one of the collateral ligaments or of the posterior capsule yielded no greater instability than one should expect from isolated cutting of each of these structures. The posterior cruciate ligament was the stabilizing factor in flexion and external rotation after injury to the lateral collateral ligament and the posterolateral capsule, and it restricted internal rotation after cutting of the medial cruciate ligament and the posteromedial capsule. Valgus instability was markedly increased during the whole range of movement when PCL was included in injury to the medial compartment ligaments, and when included in a lateral compartment injury a further varus instability was found, though only in the flexed or semiflexed knee. No hyperextension could be demonstrated after these injuries.     

The risk of anterior cruciate ligament rupture with generalised joint laxity

We assessed hyperextension of the knee and joint laxity in 169 consecutive patients who underwent an anterior cruciate ligament reconstruction between 2000 and 2002 and correlated this with a selected number of age- and gender-matched controls. In addition, the mechanism of injury in the majority of patients was documented. Joint laxity was present in 42.6% (72 of 169) of the patients and hyperextension of the knee in 78.7% (133 of 169). All patients with joint laxity had hyperextension of their knee. In the control group only 21.5% (14 of 65) had joint laxity and 37% (24 of 65) had hyperextension of the knee. Statistical analysis showed a significant correlation for these associations. We conclude that anterior cruciate ligament injury is more common in those with joint laxity and particularly so for those with hyperextension of the knee.     

The anterior cruciate ligament: a review of recent concepts

The anterior cruciate ligament (ACL) consists of a small anteromedial band and a larger posterolateral band. Recent findings have shown the ACL to play a major role in the function of the knee joint. The ACL prevents anterior luxation of the tibia, limits tibial rotation, and resists valgus and varus stress to the knee. The most common mechanism of ACL injury involves hyperextension of the knee with a rotational component. Diagnosis of an ACL lesion consists of an accurate history, clinical tests and often, arthroscopic investigation. Treatment of an ACL injury may consist solely of a rehabilitation program, may involve surgical intervention, or a combination of the two. Many surgical procedures both intra-articular and extra-articular, have been used in the past. The most successful approach at this time appears to be a combination of intra-articular and extra-articular procedures. A contemporary trend in rehabilitation following surgery is the use of graduated stages of treatment beginning immediately postsurgery and continuing through to full return to activity. J Orthop Sports Phys Ther 1986;8(3):110-122.     

Management of ACL elongation in the surgical treatment of congenital knee dislocation

Congenital knee dislocation is a rare anomaly associated with a variety of neuromuscular diseases and deformities. The etiology of this condition remains unclear, but it is usually associated with a variety of disorders, such as Larsen's syndrome, arthrogryposis, spondyloepiphyseal dysplasia, Ehlers-Danlos syndrome, Down syndrome, and Streeter's dysplasia. It is rarely an isolated entity, and 60% of patients with congenital knee dislocation had additional congenital anomalies, most commonly hip dysplasia. The ideal method of treatment is debated. No current treatment algorithms address anterior cruciate ligament (ACL) elongation and its role in recurrent deformity or hyperextension. This article describes 2 patients who underwent open reduction of the knee for recurrent and neglected congenital knee dislocations. An ACL shortening and reinforcement technique is described. Both patients' treatment consisted of V-Y advancement of the extensor mechanism, soft tissue release, anterior capsulotomy, and posterior capsulorrhaphy. Anterior cruciate ligament shortening and reinforcement using an iliotibial band physeal-sparing technique was performed. The technique improved maintenance of reduction and prevented hyperextension of the knee. Anterior cruciate ligament elongation is an underemphasized anatomical feature associated with congenital knee dislocation. Due to its role in the prevention of anterior subluxation of the tibia and its effect on knee stability, incompetence should be addressed at the time of open reduction. The presence of an intact ACL with a congenital knee dislocation does not preclude management of anterior instability. Competence of the intact ACL should be addressed following reduction.     

Incomplete avulsion of the femoral attachment of the posterior cruciate ligament with an osteochondral fragment in a twelve-year-old boy

Summary Isolated avulsion of the posterior cruciate ligament from the femoral attachment of the knee as a hyperextension injury is rare. We saw a young child with an incomplete avulsion of the posterior cruciate ligament that occurred after a blow to the anterior tibial surface of a flexed knee; the child revealed a lack of knee extension due to a pinch of the osteochondral fragment connected to the anterior band of the posterior cruciate ligament in the knee joint. Arthroscopic extirpation of a fragment was undertaken.     

Does Severity or Specific Joint Laxity Influence Clinical Outcomes of Anterior Cruciate Ligament Reconstruction?

It generally is believed generalized joint laxity is one of the risk factors for failure of anterior cruciate ligament (ACL) reconstruction. However, no consensus exists regarding whether adverse effects on ACL reconstruction are attributable to joint-specific laxity or are related to the severity of generalized joint laxity. We therefore asked whether knee stability and functional outcomes would be related to joint-specific laxity and would differ according to the severity of generalized joint laxity. The Beighton and Horan criteria were used to assess joint laxity in 272 subjects. All elements are added to give an overall joint laxity score ranging from 0 to 5. Knee translation did not increase in proportion to the severity of the generalized joint laxity. Patients with scores less than 4 showed similar knee stability. When all variables, including the severity of generalized joint laxity, were considered, only hyperextension of the knee independently predicted knee stability and function. In patients with knee hyperextension, a bone-patellar tendon-bone autograft provided superior stability and function compared with a hamstring tendon autograft. Our data suggest knee hyperextension predicts postoperative stability and function regardless whether patients have severe generalized joint laxity.     

Transsection of the peroneal nerve complicating knee arthroscopy: case report and cadaver study

We report the case of a 36-year-old male patient who sustained a hyperextension trauma of the left knee. After performing diagnostic arthroscopy (partial tear of the anterior cruciate ligament) and partial resection of the anterior cruciate ligament, the patient experienced a complete paralysis of the peroneal nerve. One year after the first surgical procedure, a reconstructive repair of the peroneal nerve and a transfer of the anterior tibial muscle was performed. This complication is reported for the first time in literature.Arthroscopy 1998 Mar;14(2):221-3     

Fracture of the radial sesamoid bone of the thumb: an unusual fracture

The hand consists of five sesamoids. Two of them are present at the metacarpophalangeal (MCP)joint of the thumb. Fracture of the sesamoid bones of the thumb is a rare injury and the literature on the radial side is seldom reported. We reported a case of a patient with a fracture of the radial sesamoid at the MCP joint of the thumb in order to increase attention regarding this type of injuries. A 44-year-old male, high level gymnastic trainer, was helping one of his athletes during an exercise while he reported a hyperextension trauma to the MCP joint of the right thumb.One week after trauma, he presented to the hand surgeon complaining of a painful thumb at the MCP joint level on its palmar aspect. Standard A-P and lateral X-rays revealed a fracture of the radial sesamoid and the fracture was treated with a splint for 3 weeks. He was able to resumed his entire work 6 weeks after the injury. The sesamoid fractures is an indicator of the magnitude of the hyperextension injury and sometimes associated with tears of the volar plate ligament of the MCP joint. And a failure to recognize the ligament injury may lead to a long-term hyperextension instability on pinching.     

膝关节周围骨折术后关节不稳的危险因素分析

目的：探讨造成膝关节周围骨折术后关节不稳的危险因素。方法从我科2010年10月至2013年7月住院患者中选取符合纳入标准的膝关节周围骨折病例116例,其中男67例,女49例,平均年龄(47.3±14.4)岁。车祸伤54例,摔伤50例,高处坠落伤6例,机器绞伤3例,殴打伤2例,重物砸伤1例。所有患者均随访12个月。选取年龄、性别、糖尿病史、原发暴力、骨折程度、开放性损伤、韧带损伤、关节囊损伤、术中出血量、手术时间、冠状位胫股角、伸直受限、屈曲受限为初筛因素,先纳入一元Logistic回归模型,再将有关联性的因素纳入多元Logistic回归模型,寻求造成膝关节周围骨折术后关节不稳的危险因素。结果一元Logistic回归分析发现,骨折程度、开放性骨折、韧带损伤、关节囊损伤情况、术中出血量和关节屈曲受限与术后关节不稳有关,差异均有统计学意义(均P<0.05)。多元Logistic回归分析发现,上述关联因素中,关节囊损伤和屈曲受限是造成膝关节周围骨折术后关节不稳的危险因素,差异均有统计学意义(均P<0.05)。结论关节囊损伤和屈曲受限是造成膝关节周围骨折术后关节不稳的主要危险因素。因此,在膝关节周围骨折的外科治疗过程中,积极修复损伤的关节囊,避免术中切开关节囊,术后早期功能锻炼,避免关节屈曲受限,能降低术后关节不稳的发生率,促进关节功能的恢复。     

A case of extensive heterotopic ossification following multiple ligament reconstruction after severe knee trauma

We present a case of extensive heterotopic ossification (HO) around the knee joint following multiple ligament reconstruction after severe trauma. A 50-year-old female sustained a motor vehicle accident and underwent multiple trauma. The initial diagnosis of the knee included avulsion fracture of the tibial attachment of the posterior cruciate ligament, multiple ligament injury including the anterior cruciate ligament and medial collateral ligament, medial and lateral meniscal tears, and the fracture of the inferior pole of the patella. The surgical treatment was delivered in 2 stages including reconstructions of the anterior and posterior cruciate ligaments reconstruction, and repair of the medial collateral ligament and menisci. At postoperative 2 months, HO was observed around the knee joint, especially on the medial and posterior aspect, and proceeded gradually. At postoperative 1 year, the ossification appears matured with clear trabeculation and round margin. The motion arc was fairly preserved from 20° to 70°. Considering the benefits and risks of the further operative management, the patient opted for conservative management. The etiology of HO is not thoroughly known, and its therapy is empiric. Although prevention is not always possible, feasible preventive measure should be exerted to avoid the irreversible pathology. This unique sequelae should be kept in mind of orthopedic surgeon to devise pertinent management plan and deliver it to the injured.     

The posterior cruciate ligament and rotatory knee instability

Summary The importance of the posterior cruciate ligament in relation to valgus-varus and axial rotatory stability in the knee joint was investigated. Mobility patterns were drawn from 20 osteoligamentous preparations after successive transection of the posterior cruciate ligament (PCL), the medial and lateral collateral ligaments, and the posterior joint capsule. The knee joint remained grossly stable after isolated transection of the PCL, and further cutting of either one of the collateral ligaments or of the posterior capsule yielded no greater instability than one should expect from isolated cutting of each of these structures. The posterior cruciate ligament was the stabilizing factor in flexion and external rotation after injury to the lateral collateral ligament and the posterolateral capsule, and it restricted internal rotation after cutting of the medial cruciate ligament and the posteromedial capsule. Valgus instability was markedly increased during the whole range of movement when PCL was included in injury to the medial compartment ligaments, and when included in a lateral compartment injury a further varus instability was found, though only in the flexed or semiflexed knee. No hyperextension could be demonstrated after these injuries

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Zusammenfassung Der Einfluß des hinteren Kreuzbandes (PCL) in bezug auf Valgus-Varus- und axialer Rotationsinstabilität wurde untersucht. Anhand von osteoligamentären Präparaten wurden Bewegungsabläufe nach schrittweiser Durchtrennung des PCL, des MCL, des LCL und der posterioren Gelenkkapsel aufgezeichnet. Nach isolierter Durchtrennung des PCL blieb das Kniegelenk im großen und ganzen stabil, auch eine kombinierte Durchtrennung eines Kollateralligamentes oder der posterioren Kapsel erzeugte keine Instabilität, die sich von der nach isolierter Durchtrennung der erwähnten Strukturen unterscheiden ließ. Nach der Durchtrennung des LCL und der lateralen posterioren Kapsel zeigte sich das PCL als stabilisierender Faktor bei Flexion und Außenrotation, und bei Innenrotation nach Durchtrennung des MCL und der medialen posterioren Kapsel. Valgus-Instabilität wurde wesentlich verstärkt während des vollen Bewegungsausschlages, wenn das PCL bei Verletzung des medialen Bandapparates mitbetroffen war. Varus-Instabilität nahm von der semiflektierten Stellung an zu, wenn das PCL bei Verletzung des lateralen Bandapparates mitbetroffen war. Nach isolierter oder kombinierter Verletzung des PCL trat in keinem Fall eine Hyperextension auf.

     

Static stabilizers of the shoulder joint

Anatomic dissection of 220 cadaver shoulders was performed to find out more about the static stabilizers of the shoulder joint. The static stabilizers, i.e. the glenohumeral ligaments, were always found to be present and strong in healthy shoulders. It was revealed that in anatomic preparations with all the organs removal except the synovial capsule, the capsule ligaments completely stabilized the joint. Anterior dislocation at 45 degrees of abduction was prevented by the superior and medial glenohumeral ligaments, while at 90 degrees of abduction the inferior glenohumeral ligament prevented dislocation. When anterior dislocation has occurred even the coracohumeral ligament must be ruptured. A new finding recorded is that the glenoid labrum is the origin of the inferior glenohumeral ligament and not a triangular static organ enlarging the socket and having a similar function to the menisci in the knee. This ligament is the most important ventral stabilizer of the humeral joint. With the conventional arthrotomy technique the medial and inferior ligaments are immediately cut through and therefore cannot be seen. The inferior glenohumeral ligament must be reconstructed in cases of anterior recurrent dislocation.     

Verdrehtrauma an Schulter- und Kniegelenk

Indirect trauma to the shoulder and knee joint often results in injuries to the ligaments and the capsule, and more rarely in fractures. Anterior shoulder dislocation is common. Over the last few years arthroscopic repair of the torn labrum has become established as the therapy of choice. Isolated ruptures of the collateral ligaments of the knee can be treated functionally. A torn anterior cruciate ligament of the knee joint can be compensated by the quadriceps muscle if this is adequately prepared by special exercises. Chronic or combined instabilities should be treated surgically by ACI grafting techniques. Menisceal injuries are treated arthroscopically.     

The anatomy of the posterolateral aspect of the rabbit knee.

The purpose of this study was to determine the anatomy of the posterolateral aspect of the rabbit knee to serve as a basis for future in vitro and in vivo posterolateral knee biomechanical and injury studies. Twelve nonpaired fresh-frozen New Zealand white rabbit knees were dissected to determine the anatomy of the posterolateral corner. The following main structures were consistently identified in the rabbit posterolateral knee: the gastrocnemius muscles, biceps femoris muscle, popliteus muscle and tendon, fibular collateral ligament, posterior capsule, ligament of Wrisberg, and posterior meniscotibial ligament. The fibular collateral ligament was within the joint capsule and attached to the femur at the lateral epicondyle and to the fibula at the midportion of the fibular head. The popliteus muscle attached to the medial edge of the posterior tibia and ascended proximally to give rise to the popliteus tendon, which inserted on the proximal aspect of the popliteal sulcus just anterior to the fibular collateral ligament. The biceps femoris had no attachment to the fibula and attached to the anterior compartment fascia of the leg.This study increased our understanding of these structures and their relationships to comparative anatomy in the human knee. This knowledge of the rabbit's posterolateral knee anatomy is important to understand for biomechanical and surgical studies which utilize the rabbit knee as a model for human posterolateral knee injuries.     

Luxationen im oberen Sprunggelenk ohne Knochenbeteiligung

Report on 3 cases of luxation in the ankle joint without fracture. It is supposed that this injury is much more freuquent than generally assumed. The fundamental pathogenetics of these injuries are discussed. There was always immobilisation in a cast following operative treatment. In one case the talus was fixed additionally by a transarticular Kirschner-wire. Because of splitting, the common suture of a ligament is problematical. It is proposed to fix the ligament under a small screw.     

Cruciate injury patterns in knee hyperextension: a cadaveric model.

We created an experimental model to evaluate the effects of strain rate on the mechanism of combined cruciate ligament injuries in knee hyperextension. Using straight knee hyperextension to rupture the anterior and posterior cruciates, two strain rates (approximately 100% per second and 5400% per second) were applied to reproduce two clinical injury patterns of the knee: low energy (sporting) and high energy (pedestrian-motor vehicle accident). Ten pairs of fresh-frozen cadaveric knees were injured to 45 degrees of hyperextension. Strain rate sensitivity of the posterior cruciate ligament was shown in this model, with midsubstance tears occuring in specimens tested at a low rate and avulsion "stripping" injuries from the femoral side occuring at a high rate. A variable pattern of anterior cruciate ligament tears at both high and low rates suggests that the specific injury mechanism may also involve other factors including notch morphology. We present a simplified mathematic model used to estimate posterior cruciate ligament strain during knee hyperextension.     

Traumatic boutonniere deformity of the thumb

We report three patients who presented 3 to 8 months after sustaining a closed injury to the dorsoradial aspect of the metacarpophalangeal joint of the thumb. All three patients had an extensor lag of the metacarpophalangeal joint and paradoxical hyperextension of the interphalangeal joint. There were no collateral ligament injuries. The patients required surgical treatment which included advancement and reattachment of the extensor pollicis brevis insertion and imbrication of the dorsoradial capsule to restore the anatomical alignment of the extensor pollicis longus. Surgical treatment of dorsoradial injuries to the thumb metacarpophalangeal joint may be required for injuries that result in subluxation of the extensor pollicis longus tendon and a boutonnière deformity of the thumb.     

Post-traumatic disorders of the jaw joint.

A group of 165 patients with surgical diseases of the temporomandibular joint treated in 3 Australian university hospitals is reviewed. A facial trauma is relatively common patients have been included in the post-traumatic group only if there was an undisputed history of injury requiring medical or dental treatment or admission to hospital. In 38.3% of patients with histologically proven osteoarthritis there was an undisputed history of trauma. In a further group with recurrent mandibular dislocation 62.6% were post-traumatic. Trauma was the cause of 62.5% of cases of mandibular ankylosis. There is a general tendency to underdiagnose degenerative joint disease and to perpetuate conservative treatment when it is crystal clear that these measures are not being successful. It is probable that intracapsular fractures of the jaw joint are frequently undiagnosed and a higher index of suspicion is required. Mandibular ankylosis continues to pose some difficulty of management and a critical review confirms that wide surgical exposure of the joint is essential; the importance of long-term review is stressed. The outcome of the surgical treatment of recurrent luxation is excellent and an operation of commendable simplicity is advocated.     

Minimally Invasive Technique for Reduction and Stabilization of Radial Head and Radial Neck Fractures in Children A Description of a Modified Technique and an Overview of the Literature

Integrity of soft tissues plays a major role in the final outcome of fractures of the proximal radius. Numerous minimally invasive operative techniques were developed to avoid additional trauma during surgical procedure. An overview over the literature is given in the present paper. We report a modified technique of Kapandji for percutaneous reduction and stabilization of displaced radial neck and radial head fractures in children. Functional results in 5 cases were good, and the children had no complaints. In one case with a luxation of the elbow and a fracture of the lateral epicondyle of humerus persitent rotation deficit was oberseved. The modified percutaneous method described here demonstrates an alternative procedure to reduce and stabilize displaced radial head and radial neck fractures. In contrast to open reduction this method avoids impairment of the anular ligament and joint capsule. Associated complex injuries of the elbow with soft tissue trauma, however, may lead to unsatisfactory functional results despite minimal operative technique and anatomic reduction.     

Irreducible open posterolateral knee dislocation due to medial meniscus interposition

Posterolateral knee dislocations are generally irreducible due to the interposition of the medial capsule and retinaculum. These injuries have a 'dimple sign' which shows the invagination of the tissues in the medial joint line. We present an unusual case of an open posterolateral traumatic knee dislocation (KD-4 [ACL/PCL/MCL/LCL-PLC torn] open knee dislocation) without a 'dimple sign'. Closed reduction attempts were unsuccessful. In surgery, it was found that the medial meniscus was detached from the meniscocapsular junction and entrapped in the joint. The medial meniscus was extracted from the joint, and the joint was reduced. The medial meniscus was sutured to the meniscocapsular junction with anchors. This is the first study reporting medial meniscus interposition in an open posterolateral knee dislocation. Moreover, the presented case is peculiar because although it was a posterolateral knee dislocation, the posterolateral ligament complex was also torn.