Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CADAVER”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources

[Is computer navigation a useful tool in unicompartmental knee arthroplasty? A pilot cadaver study].

We conducted this pilot cadaver study to investigate whether the use of a navigation system during minimally invasive unicompartmental knee arthroplasty leads to more consistent results than the conventional hand-guided technique. We describe the accuracy of implant positioning in using standard instrumentation and computer navigation. Radiographic assessment showed that accurate component placement was achieved using both methods. These results were not statistically significant. The computer navigated femoral component placement without intramedullary (IM) rod was as accurate as the conventional method with IM rod. The study showed that computer navigation can produce accurate results even without an intramedullary rod. Image guidance can maintain the accuracy of the standard instrumentation and enhance 3D vision and the intraoperative orientation of the surgeon.

Arthroplasty, Replacement, Knee↗

Minimally invasive endoscopic reconstruction technique of acute AC-joint dislocations: a cadaver study.

The treatment of acute Rockwood type III AC-joint dislocations is controversial. Problems related to open surgery are soft tissue healing, residual instability and the necessity of hardware removal. After non-operative therapy the cosmetic result may be problematic and in some cases symptomatic instabilities occur. The goal of the present cadaver study was to develop a new, minimally invasive technique for acute AC-joint reconstructions and to analyse its potential risk for neurovascular injuries. The surgical technique was based on an arthroscopically assisted reconstruction of the coracoclavicular ligaments with a suture anchor (Arthrex, Naples, FL, USA) and a supplemental stabilization of the AC-joint capsule with a suture cerclage (Fibre Wire 2, Arthrex) performed on ten cadaveric shoulder specimens. After surgery all specimens were dissected to analyse the anatomy of the coracoclavicular ligament complex, the position of anchors and sutures and to measure the distance to the neurovascular structures at risk. The supraspinatus muscle was never injured by the Neviaser approach. The insertion of the suture anchors never failed, resulting in a secure and reproducible anchor position. The mean distance between the coracoid and suprascapular nerve was 1.8 cm (1.5-2.2), between the coracoid and the suprascapular artery 1.5 cm (1.3-1.9). These structures were never injured. The resulting force vector of the suture located between the anchor and the drill hole was close to the anatomic force vector of the coracoclavicular ligament complex. The suture cerclage was always correctly positioned. The presented technique is at minimal risk for the surrounding neurovascular structures and allows for a minimally invasive and anatomically correct reconstruction of the AC-joint. Further biomechanical analysis is needed to evaluate the strength of the reconstruction technique. The proposed technique might be a reasonable alternative to existing invasive techniques of open reconstruction of acute type III AC-joint dislocations in high-demand patients.

Arthroscopy↗

Partial release of the superficial medial collateral ligament for open-wedge high tibial osteotomy. A human cadaver study evaluating medial joint opening by stress radiography.

To perform an open-wedge high-tibial osteotomy (HTO), the medial proximal tibia is frequently exposed by partial distal release of the overlying insertion of the medial collateral ligament (MCL). Biomechanically, any release of the MCL can increase knee laxity when valgus stress is applied. Clinically however, post-surgical valgus instability following HTO with partial MCL release is an uncommon complication. It is known that the open-wedge procedure can re-tention an intact MCL by the width of the base of the wedge. However, this re-tentioning effect is uncertain in small wedge sizes, preexisting medial compartment laxity and in the presence of a partially detached MCL. Considering the good clinical results after HTO, we hypothesized that a partial release of the superficial MCL for HTO does not play a crucial role in stabilizing valgus forces in the human knee. We therefore measured the effect of partial versus complete release of the superficial MCL to determine medial knee laxity represented by the amount of medial joint opening (MJO) under valgus stress in this human cadaver study. In ten knee pairs, the superficial and deep MCL were sectioned in sequence with a standardized abduction force of 15 kp with a Scheuba apparatus applied. In group 1 (5 knee pairs), the superficial MCL was completely sectioned whereas in group 2 (5 knee pairs), sectioning of the superficial MCL was restricted to the anterior border to mimic the surgical exposure for an HTO. To account for the interindividual variability of ligamentous laxity, only increments of MJO within knee pairs were statistically evaluated. Stress radiography did not reveal any significant differences in increments of MJO between knee pair specimens with complete versus partial release of the superficial MCL. We disproved our hypothesis and concluded that the anterior fibers of the superficial MCL do play a crucial role in maintaining valgus stability in this biomechanical setting. Therefore, the release of the superficial MCL for open-wedge HTO should be kept to a minimum to decrease the potential of late valgus instability. This is especially important in patients with small wedge sizes and medial compartment laxity since the anterior MCL fibers are the main contributor to medial joint stability and the re-tentioning effect of the remaining MCL fibers is presumably decreased.

Adult↗

Navigated open-wedge high tibial osteotomy: advantages and disadvantages compared to the conventional technique in a cadaver study.

High tibial osteotomy (HTO) is an established therapy for the treatment of symptomatic varus malaligned knees. A main reason for disappointing clinical results after HTO is the under- and overcorrection of the mechanical axis due to insufficient intraoperative visualisation. Twenty legs of fresh human cadaver were randomly assigned to navigated open-wedge HTO (n=10) or conventional HTO using the cable method (n=10). Regardless of the pre-existing alignment, the aim of all operations was to align the mechanical axis to pass through 80% of the tibial plateau (beginning with 0% at the medial edge of the tibial plateau and ending with 100% at the lateral edge). This overcorrection was chosen to ensure a sufficient amount of correction. Thus, the medial proximal tibia angle (MPTA) increased by 9.1+/-2.9 degrees (range 5.2 degrees -12.3 degrees ) on the average after navigated HTO and by 8.9+/-2.9 degrees (range 4.7 degrees -12.6 degrees ) after conventional HTO. After stabilization with a fixed angle implant, the alignment was measured by CT. After navigated HTO, the mechanical axis passed the tibial plateau through 79.7% (range 75.5-85.8%). In contrast, after conventional HTO, the average intersection of the mechanical axis was at 72.1% (range 60.4-82.4%) (P=0.020). Additionally, the variability of the mean corrections was significantly lower in the navigated group (3.3% vs. 7.2%, P=0.012). Total fluoroscopic radiation time was significantly lower in the navigated group (P=0.038) whereas the mean dose area product was not significantly different (P=0.231). The time of the operative procedure was 23 min shorter after conventional HTO (P<0.001). Navigation systems provide intraoperative 3-dimensional real time control of the frontal, sagittal, and transverse axis and may increase the accuracy of open-wedge HTO. Future studies have to analyse the clinical effects of navigation on corrective osteotomies.

Adult↗

Anatomic variations of the shape of the menisci: a neonatal cadaver study.

Meniscal injuries in children and adolescents are being seen with increased frequency. The menisci are two crescentic lamellae whose functions are to deepen the articular surfaces of the tibial plateu for reception of the condyles of the femur. In our study, our aim is to determine the variations of the shapes and attachments of the menisci in newborns. This study was performed on 11 neonatal cadavers, 22 knee joints that were obtained from the anatomy laboratory. The variations of the shape of the menisci were noted. We found that 77% of the lateral menisci were discoid. This percent is higher than the previously reported percents of the lateral discoid menisci. The different shapes of the menisci were determined as horse shoe, sickle, sided U, sided V and C shaped. We did not determine any discoid medial menisci. We believe that our study will provide support to the neonatal anatomy of the knee, concerning with the surgical procedures and arthroscopy of the knee joint.

Cadaver↗

Single-incision technique misses the anatomical femoral anterior cruciate ligament insertion: a cadaver study.

We examined the arthroscopic appearance of the anterior cruciate ligament (ACL) attachment site on the femur in five fresh-frozen cadaver knees. First, the ACL was cut out, leaving a footprint of ligament-fibers with a length of 2 mm intact. The ACL was consistently found to insert on the lateral wall of the notch. No fibers were found to attach high in the roof of the notch at the 12 o'clock position. Secondly, we tried to reach the anatomical attachment site with a femoral aiming guide through a correctly placed tibial tunnel. This proved to be impossible. The closest position that could be reached was at the margin of the anatomical attachment site. Investigation of the distal femur after complete dissection confirmed these arthroscopic findings. Femoral aiming devices for use through the tibial tunnel aim for an isometric placement of the femoral tunnel, they do not aim for an anatomical position of the graft.

Anterior Cruciate Ligament Injuries↗

Tendons in the plantar aspect of the foot: MR imaging and anatomic correlation in cadavers.

OBJECTIVE: The purpose of this anatomic imaging study was to illustrate the normal complex anatomy of tendons of the plantar aspect of the ankle and foot using magnetic resonance (MR) imaging with anatomic correlation in cadavers. DESIGN: Seven fresh cadaveric feet (obtained and used according to institutional guidelines, with informed consent from relatives of the deceased) were studied with intermediate-weighted fast-spin-echo MR imaging. For anatomic analysis, cadaveric specimens were sectioned in 3-mm-thick slices in the coronal and axial planes that approximated the sections acquired at MR imaging. RESULTS: The entire courses of the tendons into the plantar aspect of the foot were analyzed. The tibialis posterior tendon has a complex distal insertion. The insertions in the navicular, second, and third cuneiforms bones were identify in all cases using axial and coronal planes. A tendinous connection between the flexor hallucis longus and the flexor digitorum longus tendons was identified in five of our specimens (71%). The coronal plane provided the best evaluation. The peroneus longus tendon changes its direction at three points then obliquely crosses the sole and inserts in the base of the first metatarsal bone and the plantar aspect of the first cuneiform. CONCLUSIONS: MR imaging provides detailed information about the anatomy of tendons in the plantar aspect of the ankle and foot. It allows analysis of their insertions and the intertendinous connection between the flexor hallucis longus and the flexor digitorum longus tendons.

Aged↗

Sonography of the superomedial part of the spring ligament complex of the foot: a study of cadavers and asymptomatic volunteers.

OBJECTIVE: To evaluate the ability of high-resolution sonography for assessing the thickness and echogenicity of the superomedial part of the normal spring ligament in the foot in cadavers and asymptomatic volunteers. MATERIALS AND METHODS: The superomedial part of the normal spring ligament of four cadaveric feet was imaged with a high-resolution linear array transducer. Upon localization, the ligament was injected with 0.1% methylene blue with sonographic guidance. A posteromedial approach was used to dissect the feet immediately following injection to confirm accurate identification of the ligament. The bilateral ligaments in 40 asymptomatic adult volunteers were subsequently imaged. RESULTS: Surgical dissection confirmed the accurate injection of methylene blue into all four cadaveric ligaments. The superomedial part of the normal spring ligament was identified bilaterally in all of the 40 asymptomatic volunteers, with a mean thickness of 3 mm in longitudinal short axes. The ligament was echogenic relative to surrounding fat, and it was thinner in women. Differences in ligament measurements with respect to age, sex, side (left vs. right) and foot dominance were not significant. The volunteers' height, weight and body mass index had a weakly positive correlation with ligament thickness. CONCLUSION: High-resolution ultrasound can be used to identify and measure the thickness of the superomedial part of the normal spring ligament. The provided baseline measurements for the normal ligament could prove valuable when assessing the abnormal ligament.

Adolescent↗

Thoracoscopically assisted ligamentous release of the thoracic spine: a cadaver study.

The surgical treatment of thoracic kyphosis frequently requires an anterior release, which can be carried out by an open or endoscopic technique. This study concerns the reference points which are essential from the anatomic view for minimizing the operative risks. Furthermore we wanted to find the most convenient video-assisted thoracoscopic surgery (VATS) technique for transection of the anterior longitudinal ligament (ALL). Transection of the ALL, as well as discectomy, was performed using this technique. The extensive anatomic dissection of 12 fresh cadavers was performed to define possible technical errors and surgical complications. The development of new instruments has made the VATS approach to the ALL a viable alternative to open procedures. With the help of a standardized technique, the isolated thoracoscopic ligamentous transection required less time than the comparable open procedure. The anatomic study showed, that in no case was a ligation of the intercostal or segmental vessels necessary as part of the approach to the spine, once an adequate mobilization of the esophagus and azygos vein had been carried out. The risk of an ischemic lesion of the spinal cord was thereby reduced. The thoracoscopic, limited anterior release consisting of a multilevel transection of the ALL proved to be a rapid and reliable procedure. Our anatomic studies provides suitable the reference points.

Adult↗

Complications of Chiari and Salter osteotomies: a cadaver study.

Previous investigations of the Chiari and Salter osteotomies showed that intraoperative vessel and nerve injuries are described repeatedly in the case of both pelvic osteotomies. The aim of our investigations was the exposure of each operation step in anatomic specimens to show the anatomic landmarks and potential risks. We performed nine Chiari osteotomies and five Salter osteotomies on formalin-fixed cadavers. The operation steps were made consecutively to assess the risks to the vessels and nerves as well as the determination of anatomically important reference points. In both procedures an injury of the lateral femoral cutaneous nerve at the anterior access route is feasible. By ensuring that the skin including the lateral femoral cutaneous nerve is pulled medially, injury can be avoided. Additionally, too long retraction of the tensor fasciae latae muscle injures its nutrient vessels. An inadequate subperiosteal approach during the pull on the Hohmann's retractor leads to crushing and irritation of the sciatic nerve. Moreover, there is a risk that the superior gluteal nerve as well as the superior gluteal artery may be injured. An inadequate subperiosteal application of the medial Hohmann's retractor can endanger the obturator nerve. In the Chiari osteotomy there is a risk of injury to the articular branch of the superior gluteal nerve, which supplies parts of the ventral hip joint capsule. By inserting the K-wire too far medially the internal oblique muscle is endangered. Too prolonged retraction of the iliopsoas muscle in a Salter osteotomy can lead to compression of the femoral nerve. The form of the osteotomy has an influence on the stability of the hip joint in the course of exposure of the hip joint. On account of the narrow spatial connection between the anatomic pathways and the osteotomy area, strict subperiosteal dissection and careful use of the retractor are essential to avoid nerve and vessel injuries.

Aged↗

Arterial, neural and muscular variations in the upper limbs of a single cadaver.

Arterial, neural and muscular variations were observed in both upper limbs of a female adult cadaver during routine student dissection. Two superficial radial arteries were observed, which originated from the brachial and axillary arteries in the left and right upper limbs respectively. In the right upper limb, an ulnar nerve with a lateral root from the lateral cord of the brachial plexus in the axilla and, in the left forearm, an accessory muscle belly inserting into the muscle belly of the flexor digitorum superficialis were also observed. Formation of these variations is discussed on the basis of the embryological development of the upper limb structures. The clinical importance of the variations is emphasized.

Adult↗

Cubital tunnel release with two limited incisions: a cadaver study.

Cubital tunnel syndrome is the second most common compressive neuropathy in the upper extremity. Treatment of cubital tunnel syndrome consists of releasing the compression on the ulnar nerve with conservative or surgical methods. Nerve decompression is an alternative simple and less invasive procedure. We have proposed a "two limited incisions" technique in order to release the cubital tunnel with two minimal incisions on a cadaveric elbow model. Thirty elbows of 15 formalin-fixed cadavers were studied. The study was performed in two steps. The first step involved a two limited incisions technique. During the second step, dissected anatomic structures were assessed. The cubital retinaculum was opened totally in 27 elbows (91%) and partially in two elbows (7%). The ulnar nerve was injured in one elbow (3%), because of the contracture of the forearm muscles. It was shown that with relaxation of the elements involved, a two limited incisions technique allowed decompression of the ulnar nerve at the elbow to be performed.

Adolescent↗

Quantitation of ligament laxity in anterior shoulder instability: an experimental cadaver model.

Three groups of cadaver specimens were studied. In group 1 (20 shoulders) glenohumeral ligaments were detached from the humerus until a permanent dislocation of the humeral head occurred in abduction plus external rotation. On the dislocated joint the ligament was reconstructed using a fascia lata lengthening plasty. After the plasty had been completed, the shoulder was reduced and instability checked in the same position. Then the capsule (including the plasty) was harvested and measured. In group 2 (20 shoulders), after the plasty had been completed in the same conditions as above, the capsule was progressively reduced by 2 mm steps until the instability disappeared. Then the capsule (including the plasty) was harvested and measured. In group 3 (12 shoulders), measurements of the head and of the capsule were done. To dislocate the shoulder the section of the three glenohumeral ligaments was required. Lengthening of the capsule in group 1 was 240-250%. In all cases shortening of the capsule led to the stabilization of the shoulder. After stabilization of the shoulder was reached a residual lengthening of 175-185% was recorded. In 3 out of 4 shoulders the amount of capsule shortening required to return to a stable shoulder was between 16 and 18 mm. This experiment did not reproduce the Bankart lesion; therefore it only concerns atraumatic instability. The main limitation of this model is the low lever force that may be used to dislocate the shoulder; consequently the elasticity of the glenohumeral ligament was not taken in account. The experimental values were likely over-estimated. Nevertheless the present results provide useful information for building an experimental model of atraumatic instability of the shoulder.

Aged↗

Additional vascular compression of the brachial plexus in a cadaver with a cervical rib: case illustration.

Cervical ribs are uncommon and occur in approximately 0.5-1% of the population. The authors describe a cadaver found to have a cervical rib with further compression by the dorsal scapular artery. This vessel originated from the third portion of the subclavian artery. No other anomalies were found in this specimen. The authors speculate that some cases of symptomatic cervical rib may have an additional vector of compression from a dorsal scapular artery when it arises from the third portion of the subclavian artery. Additional studies aimed at the vascular system may be useful in diagnosis and operative planning for symptomatic patients.

Aged↗

Anatomical variations of the flexor hallucis longus muscle and the consequences for tendon transfer. A cadaver study.

The aim of this study was to evaluate the occurrence of anatomical variations of the musculotendinous junction of the flexor hallucis longus muscle. Eighty cadaver specimens preserved according to Thiel's method were assessed. Following careful dissection, the distance between the musculotendinous junction and the bone-cartilage border of the distal tibia was determined. Three typical anatomical variations were found: (1) a long lateral and shorter medial muscle belly; (2) equal-length medial and lateral muscle bellies; (3) a long medial and shorter lateral muscle belly. As a special variation in two cases only one lateral muscle belly was found. When planning a flexor hallucis longus transfer, preoperative magnetic resonance tomography (MRT) should be carried out in order to guarantee sufficient coverage of an existing soft tissue defect. These anatomical characteristics have also to be considered when interpreting ultrasonic or MRT findings in this region.

Aged↗

Histological findings of the femoral bone after cement removal in hip revision. An experimental study of cadaver femurs with two different cement removal procedures.

Cement removal in hip revision arthroplasty is often a time-consuming procedure, lengthy and tedious. Intraoperative bone damage is one of the more common complications. In the present study, the conventional cement removal method is compared with a new method by means of a histological study concerning potential negative effects to cortical or spongious bone. Histological studies on human cadaver femurs demonstrate no deleterious effects on the endosteal bone when cement was removed with this new device. The ballistically driven chiselling system (OrthoClast) is safe to the bone stock and shows no increased risk of bone damage over the conventional technique with mallet and chisel.

Arthroplasty, Replacement, Hip↗

The distal tibiofibular syndesmosis during passive foot flexion. RSA-based study on intact, ligament injured and screw fixed cadaver specimens.

INTRODUCTION: The aim of the study was to investigate the kinematics of the distal tibiofibular syndesmosis in intact and ligament injured ankles and to assess how effective is the syndesmotic screw in restraining mortise width variations during passive foot flexion. MATERIALS AND METHODS: The trials were carried out on seven fresh frozen cadaver specimens. The distal tibiofibular syndesmosis widening was investigated using Roentgen stereophotogrammetric analysis, in intact and ligament injured ankles and after the fixation of the syndesmotic screw. The AO-ASIF recommendations were followed for screw implant. RESULTS: Injury to the syndesmotic and deltoid ligaments of the ankle did not result in a significant variation of the syndesmosis behavior during passive foot flexion. The 4.5-mm diameter cortical screw used in this study proved effective in restraining mortise width variation during foot flexion. The recorded mortise widening in the flexion arc extending from the neutral to the maximally dorsiflexed position was negligible in intact and ligament injured joints. CONCLUSION: The result does not endorse the recommendation of placing the foot in full dorsal flexion during screw implantation. The choice of screw fixation as a treatment for ankle syndesmosis disruption should be carefully evaluated.

Ankle Injuries↗

Pelvic osteotomies: anatomic pitfalls at the ischium. A cadaver study.

Pelvic osteotomies for acetabular dysplasia include an osteotomy of the ischium. The potential anatomical hazards of three different osteotomies of the ischium were assessed by performing a triple osteotomy in a series of 8 fresh cadaver pelvises. An oblique osteotomy above the sacrospinous ligament using a posterior approach requires that the inferior gluteal and pudendal neurovascular bundles be mobilised and retracted. A transverse osteotomy below the sacrospinous ligament using a posterior approach can be performed in a relatively safe area between the pudendal and sciatic nerves. A transverse osteotomy from anterior can be performed through a modified Smith Peterson approach. The pudendal nerve medially, the sciatic nerve laterally and the medial circumflex artery distally are not visualised and are prone to damage.

Cadaver↗