Thuan V. Ly

The anatomy of the medial part of the knee.

BACKGROUND While the anatomy of the medial part of the knee has been described qualitatively, quantitative descriptions of the attachment sites of the main medial knee structures have not been reported. The purpose of the present study was to verify the qualitative anatomy of medial knee structures and to perform a quantitative evaluation of their anatomic attachment sites as well as their relationships to pertinent osseous landmarks. METHODS Dissections were performed and measurements were made for eight nonpaired fresh-frozen cadaveric knees with use of an electromagnetic three-dimensional tracking sensor system. RESULTS In addition to the medial epicondyle and the adductor tubercle, a third osseous prominence, the gastrocnemius tubercle, which corresponded to the attachment site of the medial gastrocnemius tendon, was identified. The average length of the superficial medial (tibial) collateral ligament was 94.8 mm. The superficial medial collateral ligament femoral attachment was 3.2 mm proximal and 4.8 mm posterior to the medial epicondyle. The superficial medial collateral ligament had two separate attachments on the tibia. The distal attachment of the superficial medial collateral ligament on the tibia was 61.2 mm distal to the knee joint. The deep medial collateral ligament consisted of meniscofemoral and meniscotibial portions. The posterior oblique ligament femoral attachment was 7.7 mm distal and 6.4 mm posterior to the adductor tubercle and 1.4 mm distal and 2.9 mm anterior to the gastrocnemius tubercle. The medial patellofemoral ligament attachment on the femur was 1.9 mm anterior and 3.8 mm distal to the adductor tubercle. CONCLUSIONS The medial knee ligament structures have a consistent attachment pattern.

The Posterolateral Attachments of the Knee A Qualitative and Quantitative Morphologic Analysis of the Fibular Collateral Ligament, Popliteus Tendon, Popliteofibular Ligament, and Lateral Gastrocnemius Tendon*

Background: Quantitative descriptions of the attachment sites of the main posterolateral knee structures have not been performed. Purpose: To qualitatively and quantitatively determine the anatomic attachment sites of these structures and their relationships to pertinent bony landmarks. Study Type: Cadaveric study. Methods: Dissections were performed and measurements taken on 10 nonpaired fresh-frozen cadaveric knees. Results: The fibular collateral ligament had an average femoral attachment slightly proximal (1.4 mm) and posterior (3.1 mm) to the lateral epicondyle. Distally, it attached 8.2 mm posterior to the anterior aspect of the fibular head. The popliteus tendon had a constant broad-based femoral attachment at the most proximal and anterior fifth of the popliteal sulcus. The popliteus tendon attachment on the femur was always anterior to the fibular collateral ligament. The average distance between the femoral attachments of the popliteus tendon and fibular collateral ligament was 18.5 mm. The popliteofibular ligament had two divisions—anterior and posterior—in all cases. The average attachment of the posterior division was 1.6 mm distal to the posteromedial aspect of the tip of the fibular styloid process and the anterior division attached 2.8 mm distal to the anteromedial aspect of the tip of the fibular styloid process. Conclusions: These structures had a consistent attachment pattern. This information will prove useful in the study of anatomic repair and reconstruction of the posterolateral structures of the knee.

Treatment of primarily ligamentous Lisfranc joint injuries: primary arthrodesis compared with open reduction and internal fixation. A prospective, randomized study.

BACKGROUND Open reduction and internal fixation is currently the accepted treatment for displaced Lisfranc joint injuries. However, even with anatomic reduction and stable internal fixation, treatment of these injuries does not have uniformly excellent outcomes. The objective of this study was to compare primary arthrodesis with open reduction and internal fixation for the treatment of primarily ligamentous Lisfranc joint injuries. METHODS Forty-one patients with an isolated acute or subacute primarily ligamentous Lisfranc joint injury were enrolled in a prospective, randomized clinical trial comparing primary arthrodesis with traditional open reduction and internal fixation. The patients were followed for an average of 42.5 months. Evaluation was performed with clinical examination, radiography, the American Orthopaedic Foot and Ankle Society (AOFAS) Midfoot Scale, a visual analog pain scale, and a clinical questionnaire. RESULTS Twenty patients were treated with open reduction and screw fixation, and twenty-one patients were treated with primary arthrodesis of the medial two or three rays. Anatomic initial reduction was obtained in eighteen of the twenty patients in the open-reduction group and twenty of the twenty-one in the arthrodesis group. At two years postoperatively, the mean AOFAS Midfoot score was 68.6 points in the open-reduction group and 88 points in the arthrodesis group (p < 0.005). Five patients in the open-reduction group had persistent pain with the development of deformity or osteoarthrosis, and they were eventually treated with arthrodesis. The patients who had been treated with a primary arthrodesis estimated that their postoperative level of activities was 92% of their preinjury level, whereas the open-reduction group estimated that their postoperative level was only 65% of their preoperative level (p < 0.005). CONCLUSIONS A primary stable arthrodesis of the medial two or three rays appears to have a better short and medium-term outcome than open reduction and internal fixation of ligamentous Lisfranc joint injuries.

Treatment of primarily ligamentous Lisfranc joint injuries: primary arthrodesis compared with open reduction and internal fixation. Surgical technique.

BACKGROUND Open reduction and internal fixation is currently the accepted treatment for displaced Lisfranc joint injuries. However, even with anatomic reduction and stable internal fixation, treatment of these injuries does not have uniformly excellent outcomes. The objective of this study was to compare primary arthrodesis with open reduction and internal fixation for the treatment of primarily ligamentous Lisfranc joint injuries. METHODS Forty-one patients with an isolated acute or subacute primarily ligamentous Lisfranc joint injury were enrolled in a prospective, randomized clinical trial comparing primary arthrodesis with traditional open reduction and internal fixation. The patients were followed for an average of 42.5 months. Evaluation was performed with clinical examination, radiography, the American Orthopaedic Foot and Ankle Society (AOFAS) Midfoot Scale, a visual analog pain scale, and a clinical questionnaire. RESULTS Twenty patients were treated with open reduction and screw fixation, and twenty-one patients were treated with primary arthrodesis of the medial two or three rays. Anatomic initial reduction was obtained in eighteen of the twenty patients in the open-reduction group and twenty of the twenty-one in the arthrodesis group. At two years postoperatively, the mean AOFAS Midfoot score was 68.6 points in the open-reduction group and 88 points in the arthrodesis group (p < 0.005). Five patients in the open-reduction group had persistent pain with the development of deformity or osteoarthrosis, and they were eventually treated with arthrodesis. The patients who had been treated with a primary arthrodesis estimated that their postoperative level of activities was 92% of their preinjury level, whereas the open-reduction group estimated that their postoperative level was only 65% of their preoperative level (p < 0.005). CONCLUSIONS A primary stable arthrodesis of the medial two or three rays appears to have a better short and medium-term outcome than open reduction and internal fixation of ligamentous Lisfranc joint injuries.

The Assessment of Intraobserver and Interobserver Error in the Measurement of Noncongenital Scoliosis in Children * 10 Years of Age

Study Design. Retrospective review of scoliosis radiographs. Objectives. To determine measurement variability in children ≤ 10 years of age with noncongenital scoliosis. Summary of Background Data. Measurement variability in congenital and adolescent idiopathic scoliosis has been studied. There is no study of measurement variability in young children with noncongenital scoliosis. Methods. A retrospective review of children ≤ 10 years of age followed for noncongenital scoliosis was performed. End vertebrae were identified on radiographs, and the curves were measured (Cobb method) twice by each of six observers. The same soft lead pencil and goniometer was used. Intraobserver and interobserver variability for continuous data was determined. Results. There were 64 children. The diagnosis was infantile/juvenile idiopathic scoliosis in 42, neuromuscular scoliosis in 7, scoliosis associated with mesenchymal disorders or other syndromes in 12, and unknown in 3 children. The curve was thoracic in 54, thoracolumbar in 8, and lumbar in 2. There were 19 left and 45 right curves. The average age was 6.6 ± 2.6 years. There were a total of 768 Cobb angle measurements with an average Cobb angle of 38 ± 22° (range, 10°–115°). Intraobserver variability was ± 6°; interobserver variability was ± 7°. Conclusion. In children ≤10 years of age with noncongenital scoliosis, intraobserver measurement variability in Cobb angle measurement is ± 6° and interobserver variability is ±7°. To be certain that there is a significant difference between Cobb angle measurements in children with noncongenital scoliosis and ≤ 10 years of age there must be a change of at least ±7°.

Anterior pelvic external fixator versus subcutaneous internal fixator in the treatment of anterior ring pelvic fractures.

Objectives: To compare the short-term results of anterior pelvic external fixation (APEF) versus anterior pelvic internal fixation (APIF) applied subcutaneously in the context of surgical treatment of pelvic ring injuries. Design: A single center retrospective chart review. Setting: A level 1 trauma center. Methods: A consecutive series of 48 patients who underwent surgical stabilization of their anterior pelvic ring (24 utilizing APIF and 24 utilizing APEF) by 2 surgeons at a single hospital were studied. The choice to use either APEF or APIF was left up to each surgeon, the indications for use are the same. Data collected included surgical or postoperative complications including infection, implant failure, reoperation, documented surgical site pain persisting to clinical follow-up visits, and radiographic union. Measurements on inlet and outlet pelvic radiographs were made immediately postoperation and at all follow-up clinic visits to determine whether there were differences in maintaining pelvic fracture reduction. Statistical analysis was performed to evaluate significant differences between the 2 groups with regard to each of these variables. Results: The APIF group was found to have a significantly lower incidence of wound complication (P < 0.05) and a lower occurrence of associated morbidity events as compared with the APEF group. In addition, the APIF group was found to have a significantly lower rate of surgical site pain persisting through all clinical follow-up intervals (P = 0.05). There was no difference between the 2 groups in terms of maintenance of pelvic reduction in the early postoperative phase or at final follow-up. No other significant differences were observed between the 2 groups. Conclusions: The present study, which was based on our initial experience with the subcutaneous anterior pelvic fixator, demonstrated encouraging clinical outcomes in terms of a lower wound complication rate and associated morbidity, and surgical site symptoms, although maintaining equivalent reduction. These findings suggest that further analysis of this technique is warranted to determine if it can be definitively recommended for general use. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Management of femoral neck fractures in young adults

Femoral neck fractures in young adults are uncommon and often the result of high-energy trauma. They are associated with higher incidences of femoral head osteonecrosis and nonunion. Multiple factors can play a significant role in preventing these devastating complications and contribute to a good outcome. While achieving an anatomic reduction and stable internal fixation are imperative, other treatment variables, such as time to surgery, the role of capsulotomy and the fixation methods remain debatable. Open reduction and internal fixation through a Watson-Jones exposure is the recommended approach. Definitive fixation can be accomplished with three cannulated or noncannulated cancellous screws. Capsulotomy in femoral neck fractures remains a controversial issue and the practice varies by trauma program, region and country. Until there is conclusive data (i.e. prospective and controlled) we recommend performing a capsulotomy. The data available is inconclusive on whether this fracture should be operated emergently, urgently or can wait until the next day. Until there is conclusive data available, we recommend that surgery should be done on an urgent basis. The key factors in treating femoral neck fractures should include early diagnosis, early surgery, anatomic reduction, capsular decompression and stable internal fixation.

The External Rotation Recurvatum Test Revisited Reevaluation of the Sagittal Plane Tibiofemoral Relationship

Background Posterolateral corner injuries can be difficult to diagnose. The external rotation recurvatum test was one of the first clinical tests described to diagnose these injuries. Since its earliest description, it has been reported that a positive test result occurred with posterior translation of the proximal tibia with respect to the distal femur as the knee went into recurvatum, external rotation, and varus angulation. Purpose To document the sagittal plane relationship of the tibiofemoral joint in patients with posterolateral knee instability and a positive external rotation recurvatum test finding, and to determine possible injury patterns associated with this test. Study Design Case series; Level of evidence, 4. Materials and Methods In a series of 134 consecutive patients with posterolateral knee injuries, all patients demonstrating a Positive external rotation recurvatum test result were identified, and bilateral hyperextension lateral radiographs were subsequently obtained to assist with preoperative planning for surgical reconstruction of their knee injuries. Results Of the 134 patients with posterolateral knee injuries, 10 demonstrated a positive external rotation recurvatum test finding. All 10 patients were noted to have a combined anterior cruciate ligament and posterolateral knee injury, with the proximal tibia noted to be subluxated anterior with respect to the distal femur on all hyperextension lateral knee radiographs. The percentage of patients with combined anterior cruciate ligament and posterolateral knee injuries with a positive external rotation recurvatum test result was 30%. Conclusion Posterolateral corner knee injuries are often difficult to diagnose, and as a result, correct interpretation of pertinent clinical knee examination findings is essential. Regarding posterolateral knee injuries, the interpretation of a positive external rotation recurvatum test result needs to be redefined to demonstrate that the tibia actually subluxates anterior to the femur, which produces an increase in genu recurvatum clinically. Moreover, the presence of a positive external rotation recurvatum test finding should alert the clinician to the presence of a probable combined posterolateral knee and anterior cruciate ligament injury.

A to p screw versus posterolateral plate for posterior malleolus fixation in trimalleolar ankle fractures.

Objectives: To compare radiographic and clinical midterm outcomes of posterior malleolar fractures treated with posterior buttress plating versus anterior to posterior lag screw fixation. Design: Retrospective case series. Setting: Level I trauma center. Patients/Participants: Between January 2002 and December 2010, patients with posterior malleolar fractures were identified by Current Procedural Terminology code and their charts reviewed for eligibility. Intervention: Posterior malleolar fixation using either anterior to posterior (AP) lag screws or posterior buttress plating. Main Outcome Measurements: Demographic data, length of follow-up, range of motion, and postoperative Short Musculoskeletal Function Assessment (SMFA) scores were the main outcome measurements. Immediate postoperative radiographs for residual gap/step-off and final follow-up radiographs for the degree of arthritis that developed were evaluated. Results: Thirty-seven patients were eligible for the study, and 27 chose to participate. Sixteen patients underwent posterior buttress plating, and 11 underwent AP screw fixation with mean follow-up times of 54.9 and 32 months, respectively. Demographic data were similar between groups. The posterolateral plating group demonstrated superior postoperative SMFA scores compared with the AP screw group with statistically significant differences in the SMFA bother index (26.7 vs. 9.2, P = 0.03) and trends toward improvement in the mobility (28.3 vs. 12.9, P = 0.08) and functional indices (20.2 vs. 9.4, P = 0.08). There were no significant differences in the range of motion or the development of ankle arthritis over time. Conclusions: Patients with trimalleolar ankle fractures in whom the posterior malleolus was treated with posterolateral buttress plating had superior clinical outcomes at follow-up compared with those treated with AP screws. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Use of an Algorithm for Classifying Acetabular Fractures: A Role for Resident Education?

BackgroundThe Letournel and Judet classification system is commonly used for classifying acetabular fractures. However, for orthopaedic surgeons with less experience with these fractures, correct classification can be more difficult. A stepwise approach has been suggested to enhance the inexperienced observer’s ability to properly classify acetabular fractures, but it is unclear whether this actually improves one’s ability.Questions/purposesWe asked (1) whether the use of a step-by-step algorithm improves residents’ ability to classify acetabular fractures, (2) whether resident experience influenced ability to correctly classify acetabular fractures, and (3) which acetabular fractures were the most difficult to classify?MethodsForty-six residents reviewed 15 sets of plain radiographs of 10 acetabular fracture patterns. Residents used the Letournel and Judet classification with only a diagram for reference. Three weeks later they were asked to classify the fractures a second time with the use of the algorithm. We then compared the number of correct responses from the two sessions and determined whether resident experience and use of the algorithm influenced correct classification.ResultsWe found an improvement in the number of correctly classified fractures between the first (348/690 [50%]) and second (409/690 [59%]) sessions. Thirty-two of 46 participants improved their score with the use of the algorithm. There was a tendency for participants with more residency training to correctly classify the fractures.ConclusionsThe algorithm provided modest improvement to the residents’ ability to classify acetabular fractures. This or other such algorithms could provide residents with a basic tool to better evaluate standard radiographs and classify acetabular fractures.