Anatomic Ligament Research Articles

Correlation of Magnetic Resonance Imaging With Knee Anterolateral Ligament Anatomy: A Cadaveric Study.

Background:Anatomic and magnetic resonance imaging (MRI) studies have recently characterized the knee anterolateral ligament (ALL). So far, no study has focused on confirming whether the evaluated MRI parameters truly correspond with ALL anatomy.Purpose:To assess the validity of MRI in detecting the ALL using an anatomic evaluation as reference.Study Design:Descriptive laboratory study.Methods:A total of 13 cadaveric knees were subjected to MRI and then to anatomic dissection. Dissection was performed according to previous anatomic study methodology. MRIs were performed with a 0.6- to 1.5-mm slice thickness and prior saline injection. The following variables were analyzed: distance from the origin of the ALL to the origin of the lateral collateral ligament (LCL), distance from the origin of the ALL to its bifurcation point, maximum length of the ALL, distance from the tibial insertion of the ALL to the articular surface of the tibia, ALL thickness, and ALL width. The 2 sets of measurements were analyzed using the Spearman correlation coefficient (ρ) and Bland-Altman plots.Results:The ALL was clearly observed in all dissected knees and MRI scans. It originated anterior and distal to the LCL, close to the lateral epycondile center, and showed an anteroinferior path toward the tibia, inserting between the Gerdy tubercle and the fibular head, around 5 mm under the lateral plateau. The ρ values tended to increase together for all studied variables between the 2 methods, and all were statistically significant, except for thickness (P = .077). Bland-Altman plots showed a tendency toward a reduction of ALL thickness and width by MRI compared with anatomic dissection.Conclusion:MRI scanning as described can accurately assess the ALL and demonstrates characteristics similar to those seen under anatomic dissection.Clinical Relevance:MRI can accurately characterize the ALL in the anterolateral region of the knee, despite the presence of structures that might overlap and thus cause confusion when making assessments based on imaging methods.

Radiographic Identification of the Deltoid Ligament Complex of the Medial Ankle

Background: An injury to the deltoid ligament complex of the ankle can require surgical intervention in cases of chronic instability. There is an absence of data describing medial ankle ligament anatomy on standard radiographic views. Purpose: To quantitatively describe the anatomic origins and insertions of the individual ligamentous bands of the superficial and deep deltoid on standard lateral and mortise radiographic views with reference to osseous landmarks and anatomic axes. Study Design: Descriptive laboratory study. Methods: Twelve nonpaired, fresh-frozen cadaveric foot and ankle specimens were utilized. Specimens were dissected free of all overlying soft tissue to identify individual ligamentous bands of the superficial and deep deltoid ligaments and to isolate their distinct origins and insertions. Footprint centers were identified on standard lateral and mortise radiographs by 2-mm stainless steel spheres embedded at the level of the cortical bone. Distances to osseous landmarks were measured independently by 2 blinded reviewers to calculate mean distances and evaluate reliability and repeatability measures using intraclass correlation coefficients. Results: Varying subsets of the 4 superficial deltoid bands including the tibionavicular (12/12), tibiospring (12/12), tibiocalcaneal (9/12), and superficial posterior tibiotalar (9/12) ligaments were found across specimens. On the lateral view, the tibionavicular ligament was the most anterior and attached 7.6 ± 1.9 mm superior and anterior to the inferior tip of the medial malleolus. The tibiospring ligament attached 12.1 ± 2.2 mm superior and anterior to the inferior tip of the medial malleolus and attached to the spring ligament, which coursed from its origin 12.3 ± 1.6 mm anterior and slightly inferior to the posterior point of the sustentaculum tali to its insertion on the navicular tuberosity. The tibiocalcaneal ligament and superficial posterior tibiotalar ligament were found posteriorly in the majority of specimens. Two constituents of the deep deltoid, including the deep anterior tibiotalar (11/12) and deep posterior tibiotalar (12/12) ligaments, were found in the majority of specimens. The deep posterior was larger and coursed from the tibia, 8.1 ± 2.2 mm posterior and superior to the inferior tip of the medial malleolus, to its attachment on the talus, 15.5 ± 2.4 mm superior and anterior to the posterior inferior point of the talus on the lateral view. Conclusion: Quantitative radiographic relationships describing the anatomic origins and insertions of the individual superficial and deep deltoid constituents were defined with excellent reliability and reproducibility. Clinical Relevance: Radiographic parameters will augment current anatomic data by assisting with preoperative planning, intraoperative guidance, and postoperative assessment. These radiographic guidelines will facilitate the development of novel anatomic reconstructions and allow surgeons to plan the locations of reconstruction tunnels.

Assessment of the feasibility of arthroscopic visualization of the lateral ligament of the ankle: a cadaveric study.

An anatomical study was performed to assess the feasibility of arthroscopic visualization of the lateral ligaments of the ankle. The fibular, talar and calcanear insertions of the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) were identified by standard arthroscopy portals. After dissection of the ATFL and CFL, bone tunnels were created at the estimated centres of their footprints. Dissection was then performed to identify the footprints and their position in relation to bony landmarks. The distance from the real centre of the footprint to the corresponding tunnel entrance was measured. Fourteen fresh frozen ankles were included. The ATFL and CFL were identified in all cases. The centre of the fibular ATFL footprint was found to be 16.1±3.5mm from the tip of the fibula, and the talar footprint was 18.4±2.8mm from the apex of the lateral talar process. The centre of the fibular CFL footprint was 4.2±0.8mm from the tip of the fibula, and the calcaneal footprint was 18.4±2.5mm from the fibular process of the calcaneum. The fibular tunnel was 2.9±3mm proximally from the centre of the ATFL fibular footprint, the talar tunnel was 4.4±3.2mm proximally from the centre of the talar footprint, and the calcaneal tunnel was 3.3±2.8mm too anterior from the CFL calcaneal footprint. No iatrogenic lesions were noted. Arthroscopic identification of the ATFL, CFL and their corresponding footprints can be considered safe and reliable. Tunnels entrances, in preparation for arthroscopic ligament reconstruction, are precisely positioned. Arthroscopic anatomical ligament reconstruction is a feasible option.

Significance of medial patello-femoral ligament in support of patella stability: features of anatomy and biomechanics

The purpose of the study - anatomical and biomechanical substantiation of medial patellofemoral ligament (MPFL) reconstruction in cases of recurrent patella dislocation. Material and methods. Anatomical studies were performed in 27 fresh frozen cadaver knees. Biomechanical study was made using video capture system with 5 specimens of the knee. In the first stage we examined the lateral displacement of the patella when the knee was flexing, and in the second - isometric properties of the MPFL. Results. In all cases MPFL was found between the knee capsule and the superficial fascia. In 6 (22.2%) cases singlebundle structure was revealed, in 14 (51.8%) - two-bundle and in 2 (7.4%) - three-bundle structure. In 2 (7.4%) knee joints MPFL was presented in one thinned bundle, attached to the upper third of the patella. The degree of the MPFL isometry was indicated by changing in the distance between the optical markers located in the regions of attachment of MPFL ligament. For all of the knees this distance had reached 58.3±1.2 mm tibia in knee flexion at 20°; 57.8±,4 mm - when flexed by 30°; 56.9±1,3 mm - at 45°; 56.8±1,3 mm - at 60° of flexion and 53.0±0,7 mm - at 90°. Conclusion. There are several variants of MPFL anatomical structure, and in most cases it has two bundles oriented to the medial surface of the knee from posterior to anterior and from proximal to distal directions. MPFL has a streak of isometry, as a normal characteristic of each anatomical ligament and this isometry must be followed in MPFL reconstruction in case of recurrent patella dislocation.

Radiographic Identification of the Syndesmotic Structures of the Ankle

Objectives:Syndesmotic ligament sprains may result in significant time lost from sport and can lead to chronic pain and instability. While syndesmotic anatomy has been well-defined, quantitative radiographic guidelines for identifying the anatomic ligament attachment sites and tibiofibular cartilage surfaces have not been adequately defined. The purpose was to define quantitative radiographic guidelines for identifying the origins and insertions of the syndesmotic ligaments and tibiofibular articulating cartilage surfaces with respect to radiographic landmarks and standard reference lines.Methods:Twelve non-paired fresh-frozen ankles were dissected to identify the attachments of the anterior inferior tibiofibular ligament (AITFL), posterior inferior tibiofibular ligament (PITFL), interosseous tibiofibular ligament (ITFL), and the cartilage surfaces of the tibiofibular articulation. The center of each structure was marked with a 2 mm radiopaque sphere at the level of the cortex. Standard lateral and mortise radiographs were obtained using a fluoroscopy c-arm and calibrated using a 25.4 mm diameter radiopaque sphere positioned in the field of view. Using a picture archiving and communications system, measurements were performed twice by two independent raters to calculate intra- and inter-rater reliability via intraclass correlation coefficients (ICCs).Results:Measurements demonstrated excellent agreement between raters and across trials (All inter- and intra-rater ICCs ≥ 0.960) for all structures and radiographic views. On the lateral view, the AITFL tibial origin was 9.6 ± 1.5 mm superior and posterior to the anterior tibial plafond (Table 1). Its fibular insertion was 4.4 ± 1.7 mm superior and posterior to the anterior fibular tubercle. The superficial PITFL originated 7.4 ± 1.6 mm superior to the posterior plafond and inserted 22.0 ± 2.3 mm superior and posterior to the lateral malleolus. The corresponding measurements for the deep PITFL were 3.2 ± 1.5 mm superior and 15.4 ± 3.4 mm superior and posterior, respectively. The proximal and distal edges of the ITFL tibial origin were 45.9 ± 7.9 mm and 12.4 ± 3.4 mm proximal to the central aspect of the plafond respectively. The center of the tibiofibular contact area was 8.4 ± 2.1 mm posterior and superior to the anterior plafond. On the mortise view, the AITFL tibial attachment was 5.6 ± 2.4 mm medial and superior to the lateral extent of the plafond and its fibular insertion was 21.2 ± 2.2 mm superior and medial to the lateral malleolus. The corresponding superficial PITFL measurements were 2.7 ± 1.7 mm and 21.5 ± 3.2 mm respectively. The ITFL distal tibial margin was 11.1 ± 3.5 mm proximal to the tibial plafond.Conclusion:Radiographic measurements demonstrated excellent agreement among reviewers and across trials suggesting clinical reproducibility and surgical utility of the defined parameters. Regardless of the type of surgical treatment, these parameters will assist with preoperative planning, augment intraoperative navigation, and provide additional means for objective post-operative assessment of hardware and tunnel placement. Furthermore, radiographic landmarks may be of particular use in revision or arthroscopic assisted cases where surgical landmarks may be obscured or not readily visible.

The shoulder.

The shoulder.

Surgical Treatment of Acute Grade III Medial Collateral Ligament Injury Combined With Anterior Cruciate Ligament Injury: Anatomic Ligament Repair Versus Triangular Ligament Reconstruction

The purpose of this study was to evaluate the clinical results of medial collateral ligament (MCL) anatomic ligament repair (ALR) and triangular ligament reconstruction (TLR) in treating acute grade III MCL injury with respect to imaging and functional results. Between January 2009 and October 2011, a total of 69 patients with an acute grade III MCL tear combined with an anterior cruciate ligament tear were divided into 2 groups: those who underwent ALR and those who underwent TLR. Single-bundle anterior cruciate ligament reconstruction was also performed in all patients. A radiographic stress-position imaging test was performed to evaluate excessive medial opening of the knee. In addition, the Slocum test was carried out to assess anteromedial rotatory instability before surgery and at follow-up. The subjective symptoms and functional outcomes were evaluated preoperatively and postoperatively with International Knee Documentation Committee (IKDC) assessment. Sixty-four patients with a mean follow-up period of 34months were included in the final analysis. The measurement results for medial opening at the last follow-up appointment decreased significantly from the pretreatment measurements and fell within the normal range, without a statistically significant difference between the 2 groups (P > .05). The overall incidence of anteromedial rotatory instability was reduced to 21.9% compared with 62.5% preoperatively. However, the incidence of anteromedial rotatory instability in the TLR group (9.4%) decreased significantly compared with that in the ALR group (34.4%) (P < .05). All patients' IKDC subjective scores significantly improved after surgery. No statistically significant difference was found between the 2 groups at the last follow-up (P > .05). The comparison of IKDC extension and flexion deficit scores between the 2 groups showed no significant differences. Eleven patients in the ALR group and 4 in the TLR group complained of medial knee pain. The comparison between the 2 groups showed no significant difference (P > .05). The clinical outcomes of this study showed that no major difference existed in the ALR and TLR groups based on IKDC scores and medial opening evaluations in the short-term. However, TLR offered better rotatory stability than ALR at final follow-up. Level II, lesser-quality randomized controlled trial.

Ankle instability: presentation and management

Abstract The ankle joint is akin to a mortise. Damage to this mortise joint with injury to either the medial, lateral or syndesmotic complex can result in chronic ankle instability. In this article we discuss the management of ankle instability, most commonly arising from injuries to the lateral ligament complex. Chronic ankle instability may develop from an inversion-type ankle sprain, usually affecting the anterior talo-fibular ligament (ATFL). Most affected patients improve with conservative management following this injury, but up to 30% of patients can develop debilitating chronic ankle symptoms. In assessing ankle instability it is important to differentiate between patients with functional instability and those with mechanical instability. Clinical assessment is the cornerstone of diagnosis, although stress views performed under anaesthesia (including the contralateral ankle for comparison) are useful. MRI is helpful in the assessment of soft tissue and cartilage injury. Short periods of immobilisation and physiotherapy are the mainstay of acute treatment. Patients with functional instability may benefit from peroneal strengthening and proprioceptive rehabilitation. Surgery is recommended for patients with mechanical instability who fail conservative treatment. Anatomical ligament repair has the best results. Non-anatomic ligament reconstruction is reserved for revision cases although primary ligament reconstruction may have a role in selected cases.

Imaging of peritoneal ligaments by endoscopic ultrasound (with videos).

Double layered peritoneal folds or ligaments act as conduits for the passage of blood vessels in intraperitoneal organs and also provide a pathway for the spread of disease. It is difficult to identify these normal peritoneal folds at imaging. Computed tomography is the most common imaging modality used to detect diseases of the peritoneum. The ultrasound (US) has been also used for evaluation of diseases involving ligaments. Endoscopic ultrasound (EUS) is being increasingly used both for diagnostic and interventional purposes in abdomen. In this article, we have described the normal EUS anatomy of the peritoneal ligaments.

Arthroscopic assisted femoral tunnel drilling for the intra-articular anatomic cranial cruciate ligament reconstruction in dogs.

To develop and test an arthroscopic aiming device for extra- to intra-articular femoral tunnel drilling emerging at the center of the femoral insertion of the cranial cruciate ligament (CrCL) in medium to large breed dogs. Hindlimbs (n=12) of six cadaveric dogs (≥20kg bodyweight). One hindlimb from each cadaver was randomly chosen. On a standard medio-lateral stifle radiograph the caudo-cranial position of the CrCL center was measured and transferred onto an adjustable aiming device. After arthroscopic debridement of the CrCL the aiming device was hooked behind the lateral condyle and a 2.4mm guide pin was placed from extra- to intra-articular. The intra-articular position of the resulting bone tunnel was evaluated radiographically as well as compared to the anatomic CrCl center of the contralateral hindlimb using 3D renderings. According to the postoperative radiographs all six drill tunnels were located at or near the CrCL center. The median absolute 3D error from the anatomical center of the CrCL was 0.6mm (range: 0.2-0.9mm). Precise anatomic placement of the femoral tunnel for intra-articular repair of the CrCL was achieved using an adjustable aiming device. The proposed technique will reduce femoral tunnel misplacement when performing intra-articular CrCL repair in dogs. In combination with the published technique for arthroscopic tibial tunnel drilling using a similar aiming device, the technical requirements for arthroscopic assisted tunnel positioning for anatomical graft replacement are available.

Radiographic Anatomy of the Native Anterior Cruciate Ligament: a Systematic Review.

In an attempt to improve the accuracy and reproducibility of tunnel positioning, radiographs are being analyzed in an attempt to recreate the native anatomy of the ACL. Understanding the native ACL radiographic anatomy is an essential prerequisite to understand the relevance of postoperative tunnel position. We performed a systematic review of the literature to delineate the radiographic location of the native ACL femoral and tibial footprints. A search was performed in March 2014 in PubMed, the Cochrane Collaboration Library, and EMBASE to identify all studies that evaluated the native anterior cruciate ligament (ACL) anatomy on radiographs. Various measurement methods were used in each study, and averages were obtained of the data from studies with the same measurement methods. Fifteen papers were identified (which included data on 177 femora and 207 tibiae in total). Evaluation of the femoral footprint using the quadrant method on lateral knee radiographs showed that the average percent distance location of the anteromedial (AM) bundle and posterolateral (PL) bundle was 22.8% (95% confidence interval (CI) 16.59-28.90) and 32.5% (95% CI 27.71-37.26) from the posterior condyle, respectively, and 23.2% (95% CI 19.52-26.94) and 50.0% (95% CI 46.16-53.76) from Blumensaat's line, respectively. Using the Amis and Jacob method, the tibial footprint on the lateral knee radiograph average percent distances was 35.1% (95% CI 34.46-35.72) for the center of the AM bundle and 47.3% (95% CI 41.69-52.95) for the center of the PL bundle of the ACL. The femoral and tibial ACL footprints on the anteroposterior (AP) views of the knee were not well delineated by these studies. The information presented in this systematic review offers surgeons another important tool for accurate ACL footprint identification.

Arthroscopy for Bennett fractures: A prospective series of 8 cases

The Bennett fracture is a trauma associating an intra-articular fracture of the first metacarpal and a trapezio-metacarpal joint subluxation; the prognosis of this trauma depends on quality of reduction and preservation of ligamentous anatomy. This prospective case series aims at demonstrating that arthroscopic procedure for Bennett fractures can improve both the quality of reduction and the preservation of ligamentous anatomy. Over a period of 18 months, 8 intra-articular fractures of the first metacarpal were operated on with arthroscopy. We only retained recent (< 21 days) trauma without extra-articular fracture. We used 2 portals, a 1.9 mm arthroscope, percutaneous cannulated screws and an adhesive strip for closure, a gauntlet splint for 3 weeks followed by an active/passive physiotherapy. Physical examination and X-ray were performed after 3, 6 and 12 weeks. Analysis criteria were: – peroperative: ligament impairment, duration of surgery; – postoperative: pain, trapezio-metacarpal motion (Ant-Retropulsion, Abd-Adduction, Kapandji score), key pinch strength, time off work and sports, X-ray analysis (reduction, consolidation, secondary displacement). All patients were reviewed 3 times. The duration of surgery went down from 60 to 20 minutes; a partial fracture of the trapezium was found in 2 cases; the collateral volar-ulnar ligament was impaired in 2 cases. Active range of motion was: – 3 weeks: Ant 30° – Retro 0°, Abd 20° – Add 5°, Kapandji 4; – 6 weeks: Ant 50° – Retro 10°, Abd 40° – Add 15°, Kapandji 8, key pinch strength 70%; – 12 weeks: Ant 50° – Retro 10°, Abd 40° – Add 15°, Kapandji 10, strength 90%. One patient was still experiencing pain under strain after 12 weeks despite good joint stability. We noticed 7 anatomic reductions and no secondary displacement. Time off work was 4 weeks (1–6); time off upper limb sports was 8 weeks (6–12). Functional mobility was regained after 6 weeks, accompanied by good strength. Arthroscopy seems to be a reliable and efficient procedure for Bennett fractures. Recovery and functional outcomes are at least the same as with an open procedure, whereas arthroscopy reduces morbidity and duration of surgery.

Biological Solutions to Anatomical Acromioclavicular Joint Reconstruction

Acromioclavicular (AC) joint injuries are frequent injuries in athletes, typically resulting from a fall onto the lateral aspect of the acromion with the arm in an adducted position. AC joint stability depends primarily on the AC and coracoclavicular (CC) ligaments. Treatment is typically nonoperative for types I and II injuries and operative for types IV, V, and VI injuries. Type III injuries involve disruption of both the AC and CC ligaments, and controversy surrounds the indications for nonoperative vs operative treatment for these injuries. Multiple surgical options have been described for AC instability, including CC screw fixation, coracoacromial ligament transfer, and numerous methods of anatomical CC ligament reconstruction. CC ligament reconstruction can be performed either open or arthroscopically, with various combinations of allograft, autograft, synthetic ligaments, and suture materials. The purpose of this review is to discuss biological solutions to anatomical CC ligament reconstruction. In addition, the authorsʼ preferred techniques for biological AC reconstruction have been discussed.

Ankle Syndesmosis

Background: Syndesmosis sprains can contribute to chronic pain and instability, which are often indications for surgical intervention. The literature lacks sufficient objective data detailing the complex anatomy and localized osseous landmarks essential for current surgical techniques. Purpose: To qualitatively and quantitatively analyze the anatomy of the 3 syndesmotic ligaments with respect to surgically identifiable bony landmarks. Study Design: Descriptive laboratory study. Methods: Sixteen ankle specimens were dissected to identify the anterior inferior tibiofibular ligament (AITFL), posterior inferior tibiofibular ligament (PITFL), interosseous tibiofibular ligament (ITFL), and bony anatomy. Ligament lengths, footprints, and orientations were measured in reference to bony landmarks by use of an anatomically based coordinate system and a 3-dimensional coordinate measuring device. Results: The syndesmotic ligaments were identified in all specimens. The pyramidal-shaped ITFL was the broadest, originating from the distal interosseous membrane expansion, extending distally, and terminating 9.3 mm (95% CI, 8.3-10.2 mm) proximal to the central plafond. The tibial cartilage extended 3.6 mm (95% CI, 2.8-4.4 mm) above the plafond, a subset of which articulated directly with the fibular cartilage located 5.2 mm (95% CI, 4.6-5.8 mm) posterior to the anterolateral corner of the tibial plafond. The primary AITFL band(s) originated from the tibia 9.3 mm (95% CI, 8.6-10.0 mm) superior and medial to the anterolateral corner of the tibial plafond and inserted on the fibula 30.5 mm (95% CI, 28.5-32.4 mm) proximal and anterior to the inferior tip of the lateral malleolus. Superficial fibers of the PITFL originated along the distolateral border of the posterolateral tubercle of the tibia 8.0 mm (95% CI, 7.5-8.4 mm) proximal and medial to the posterolateral corner of the plafond and inserted along the medial border of the peroneal groove 26.3 mm (95% CI, 24.5-28.1 mm) superior and posterior to the inferior tip of the lateral malleolus. Conclusion: The qualitative and quantitative anatomy of the syndesmotic ligaments was reproducibly described and defined with respect to surgically identifiable bony prominences. Clinical Relevance: Data regarding anatomic attachment sites and distances to bony prominences can optimize current surgical fixation techniques, improve anatomic restoration, and reduce the risk of iatrogenic injury from malreduction or misplaced implants. Quantitative data also provide the consistency required for the development of anatomic reconstructions.

Breast ligaments: an anatomical study

Background Although the anatomy of the breast, and in particular the ligamentous system, has been widely studied for decades, there is still some controversy regarding some specific anatomical structures. The aims of this study were the ligamentous anatomy of the female breast through cadaveric dissection and to establish relationships with anthropometric and physiological data.

Arthroscopic Anatomic Reconstruction of the Lateral Ligaments of the Ankle With Gracilis Autograft

Lateral ankle sprains are common; if conservative treatment fails and chronic instability develops, stabilization surgery is indicated. Numerous surgical procedures have been described, but those that most closely reproduce normal ankle lateral ligament anatomy and kinematics have been shown to have the best outcomes. Arthroscopy is a common adjunct to open ligament surgery, but it is traditionally only used to improve the diagnosis and the management of any associated intra-articular lesions. The stabilization itself is performed open because standard anterior ankle arthroscopy provides only partial visualization of the anterior talofibular ligament from above and the calcaneofibular ligament attachments cannot be seen at all. However, lateral ankle endoscopy can provide a view of this area that is superior to open surgery. We have developed a technique of ankle endoscopy that enables anatomic positioning of the repair or fixation of the graft. In this article we describe a safe and reproducible arthroscopic anatomic reconstruction of the lateral ligaments of the ankle using a gracilis autograft. The aim of this procedure is to obtain a more physiological reconstruction while maintaining all the advantages of an arthroscopic approach.

Pelvic ring fractures: what the orthopedic surgeon wants to know.

Treating trauma patients with displaced pelvic fractures requires a multidisciplinary approach at a designated trauma center to reduce morbidity and mortality. Immediate recognition of pelvic ring disruption and determination of pelvic stability are critical components in the evaluation of such patients. Stability is achieved by the ability of the osseoligamentous structures of the pelvis to withstand physiologic stresses without abnormal deformation. The supporting pelvic ligaments, including the posterior and anterior sacroiliac, iliolumbar, sacrospinous, and sacrotuberous ligaments, play a crucial role in pelvic stabilization. Radiologists should be familiar with the ligamentous anatomy and biomechanics relevant to understanding pelvic ring disruptions, as well as the Young and Burgess classification system, a systematic approach for interpreting pelvic ring disruptions and assessing stability on the basis of fundamental force vectors that create predictable patterns. This system provides an algorithmic approach to interpreting images and categorizes injuries as anterioposterior (AP) compression, lateral compression, vertical shear, or combined. Opening and closing of the pelvis from rotational forces result in AP compression and lateral compression injuries, respectively, whereas vertical shear injuries result from cephalad displacement of the hemipelvis. AP and lateral compression fractures are divided into types 1, 2, and 3, with increasing degrees of severity. Knowledge of these injury patterns leads to prompt identification and diagnosis of other subtle injuries and associated complications at pelvic radiography and cross-sectional imaging, allowing the orthopedic surgeon to apply corrective forces for prompt pelvic stabilization.

Spectrum of carpal dislocations and fracture-dislocations: imaging and management.

The objectives of this article are to discuss the imaging of carpal dislocations and fracture-dislocations and to review the ligamentous anatomy of the wrist, mechanisms of injury, and routine management of these injuries. Perilunate dislocations, perilunate fracture-dislocations (PLFDs), and lunate dislocations are high-energy wrist injuries that can and should be recognized on radio-graphs. These injuries are a result of important sequential osseous and ligamentous injuries or failures. Prompt and accurate radiographic diagnosis aids in the management of patients with perilunate dislocations, PLFDs, and lunate dislocations while assisting orthopedic surgeons with subsequent surgical planning. CT may better show the extent of the injury and help in treatment planning particularly in cases of delayed treatment or chronic perilunate dislocation. A CT examination with coronal, sagittal, and 3D reformatted images is ordered at our institution in cases in which the extent of the carpal injuries is poorly shown on radiographic examination.

Anatomic double-bundle reconstruction with free tendon graft for chronic ulnar instability of the thumb metacarpophalangeal joint.

Failed primary treatment of thumb metacarpophalangeal ligament injuries may lead to chronic instability. Different treatments have been described such as secondary ligament suture, fusion, dynamic or static procedures. Techniques to restrain the joint stability with various grafts of different configurations have been published, but most of these address only the proper collateral ligament. Experimental data revealed the importance of the accessory collateral ligament in stabilizing the metacarpophalangeal joint. In a former, true anatomic ligament reconstruction a bone-tendon graft was used; the tendon was split longitudinally to reconstruct both parts of the collateral ligament. This technique was modified by the author: a resorbable interference screw was used to fix a free tendon graft double in the metacarpal head, creating 2 identical bundles for reconstruction of both the proper and the accessory collateral ligament. The results of the first 10 patients with chronic ulnar instability in their otherwise intact thumb are reported. The mean follow-up was 15 months. Eight patients had excellent result and 2 patients had good result according to the Glickel grading system. The mean loss of motion in the metacarpophalengeal joint was 9% and the mean loss of pinch strength was 9% compared with the contralateral thumb. The technical details, pitfalls, complications, and rehabilitation are described in this paper.

The 2014 ABJS Nicolas Andry Award: The puzzle of the thumb: mobility, stability, and demands in opposition.

The paradoxical demands of stability and mobility reflect the purpose and function of the human thumb. Its functional importance is underscored when a thumb is congenitally absent, injured, or afflicted with degenerative arthritis. Prevailing literature and teaching implicate the unique shape of the thumb carpometacarpal (CMC) joint, as well as its ligament support, applied forces, and repetitive motion, as culprits causing osteoarthritis (OA). Sex, ethnicity, and occupation may predispose individuals to OA. What evidence links ligament structure, forces, and motion to progressive CMC disease? Specifically: (1) Do unique attributes of the bony and ligamentous anatomy contribute to OA? (2) Can discrete joint load patterns be established that contribute to OA? And (3) can thumb motion that characterizes OA be measured at the fine and gross level? We addressed the morphology, load, and movement of the human thumb, emphasizing the CMC joint in normal and arthritic states. We present comparative anatomy, gross dissections, microscopic analysis, multimodal imaging, and live-subject kinematic studies to support or challenge the current understanding of the thumb CMC joint and its predisposition to disease. The current evidence suggests structural differences and loading characteristics predispose the thumb CMC to joint degeneration, especially related to volar or central wear. The patterns of degeneration, however, are not consistently identified, suggesting influences beyond inherent anatomy, repetitive load, and abnormal motion. Additional studies to define patterns of normal use and wear will provide data to better characterize CMC OA and opportunities for tailored treatment, including prevention, delay of progression, and joint arthroplasty.