Soft tissue metastases in lung cancer: a review of the literature.

BACKGROUND: In lung cancer patients, metastases to soft tissues (STs), including skeletal muscle, subcutaneous tissue and skin, are rarely reported. Besides, lung cancer, primary carcinomas of the kidney and colon are the most commonly associated with ST metastases. AIM: To determine the prevalence, clinical-pathological features and treatment options of ST metastases originating from lung carcinoma. MATERIALS AND METHODS: A literature search was performed using the following terms: lung cancer, ST metastasis, skeletal muscle metastasis, cutaneous metastasis, subcutaneous metastasis. RESULTS: Autopsy series have detected STs metastases in 0.75-9% of patients who died from metastatic lung carcinoma. Pain and the presence of a palpable mass are the most frequent clinical features. The biopsy is recommended after MRI for diagnosis. Due to the rarity of ST metastases, the differential diagnosis must be posed especially with primary ST sarcomas. The type of treatment depends on the patient's clinical status and prognosis, and includes observation, radiotherapy, chemotherapy and surgery. CONCLUSIONS: In lung cancer patients, ST metastases are rare, but not exceptional. Their presence should be suspected in the presence of a palpable mass either painful or asymptomatic. Radiological and histological examinations are required for the definite diagnosis. The choice of treatment should be based on considerations related to the stage of the primary tumor and the patient's global health status.

Comparison between 2D and 3D computed tomography evaluation of glenoid bone defect in unilateral anterior gleno-humeral instability.

PURPOSE: This study evaluated the agreement between 2D and 3D computed tomography (CT) measurements in identifying the size and type of glenoid-bone defect in anterior glenohumeral instability. MATERIALS AND METHODS: One hundred patients affected by unilateral anterior glenohumeral instability underwent a CT of both shoulders. Images were processed with both 2D [multiplanar reconstruction (MPR)] and 3D [volumerendering (VR)] methods. The area of the missing glenoid was calculated in comparison with the healthy glenoid and expressed as a percentage. Agreement between the two measurements was assessed according to the Bland-Altman method; a 5% mean difference was considered as clinically relevant. RESULTS: Analysis of agreement between MPR and VR measurements of the percentage of missing glenoid showed a mean difference equal to 0.62%±1.96%. Percent agreement between the two measurements in detecting the presence of bone defect was 97% (p<0.0001). Percent agreement between the two measurements in discriminating the type of bone defect was 97% (p<0.0001). CONCLUSIONS: Agreement between 2D (MPR) and 3D (VR) CT measurements to identify the size and type of glenoid-bone defect in anterior glenohumeral instability was so high that the two measurements can be considered interchangeable.

The effect of autologous conditioned plasma on the treatment of focal chondral defects of the knee. An experimental study.

The purpose of the present study was to evaluate the effect of local application of Autologous Conditioned Plasma (ACP) on the treatment of full-thickness cartilage injuries of the knee. The hypothesis of the study was that ACP can enhance healing response of injured cartilage. A full-thickness chondral lesion on the weight-bearing area of the medial femoral condyle was performed in 30 sheep. Animals were divided into 2 groups, according to postoperative treatment: in group 1, weekly injections of ACP for five times were performed; in group 2, lesions were left untreated. Animals were sacrificed at 3, 6 and 12 months after treatment. A histological evaluation was performed according to a modified O'Driscoll histological score. Comparison between groups for each time interval was performed with the Student's t-test. Significance was set at P<0.05. A post-hoc power analysis was performed according to the hypothesis of the study. Histological evaluation at 3 and 6 months showed that group 1 had significantly greater total score than group 2. At 12 months, no significant difference was observed between groups. In conclusion, local injections of ACP for treatment of full-thickness cartilage injuries did not produce hyaline cartilage. However, it promoted reparative response of the cartilage defect until 6 months after treatment.

The effect of platelet rich plasma combined with microfractures on the treatment of chondral defects: an experimental study in a sheep model.

OBJECTIVE: To evaluate the effect of autologous platelet rich plasma (PRP) combined with microfractures on the treatment of chondral defects. The hypothesis of the study was that PRP can enhance cartilage repair after microfractures. METHODS: A chronic full-thickness chondral lesion of the medial femoral condyle was performed in 15 sheep. Animals were divided into three groups, according to treatment: group 1: microfractures; group 2: microfractures+PRP and fibrin glue gel; group 3: microfractures+liquid-PRP injection. Animals were sacrificed at 6 months after treatment. Macroscopic appearance was evaluated according to International Cartilage Repair Society (ICRS) score; cartilage stiffness was analyzed with an electromechanical indenter (Artscan 200); histological appearance was scored according to a modified O'Driscoll score. Comparison between groups for each outcome was performed with Kruskal-Wallis test, and Tukey's test for pairwise comparisons. RESULTS: Macroscopic ICRS score of group 2 was significantly better than those of the other groups, and score of group 1 was significantly lower than those of the other groups. Scores of group 1 and 3 were significantly lower than that of normal cartilage. Mean cartilage stiffness of groups 1 and 3 was significantly lower than that of normal cartilage. Histological total scores of group 2 and 3 were significantly better than that of group 1. CONCLUSIONS: PRP showed a positive effect on cartilage repair and restoration after microfractures. The procedure was more effective when PRP was used as a gel in comparison with liquid intra-articular injection. Histological analysis revealed that none of experimental treatments produced hyaline cartilage.

Infection following bone tumor resection and reconstruction with tumoral prostheses: a literature review.

Bone resection is the choice treatment of malignant bone tumors. Tumor prosthesis is one of the most common solutions of reconstruction following resection of bone tumor located to the metaphysis of long bones. Periprosthetic infections are a frequent complication of limb-salvage surgery which is largely due to prolonged and repeated surgeries, as well as to the immunocompromised condition of these patients due to neoplastic treatment. Furthermore, the large exposure of tissues during this type of surgery and the dissection across vascular distributions also contributes to the high risk of infection. The authors reviewed the literature discussing the incidence of infections of tumor prosthesis implanted following resection of bone tumors, taking into account the different sites of implantation. In the English literature, the highest risk of infection which led to limb amputation was observed after proximal tibia resection and this difference was considered to be due to the poor condition of soft tissue and also after pelvic resection due to huge dead space after sarcoma resection not filled by implant. Independent of the location, the management of infected prosthesis is similar. That is, after one or more attempts at debridement and antibiotic therapy, it consists of implant removal and insertion of a new implant in a one- or two-stage procedure, with a decreased risk of failure with the two-stage procedure.

Local infusion of norepinephrine reduces blood losses and need of transfusion in total knee arthroplasty.

Blood loss after total knee arthroplasty (TKA) is often associated with cardiovascular complications and a high transfusion rate of allogenic blood. In our study we focused our attention on developing a new intra-surgical procedure that appears safe, easy to perform and effective in the reduction of bleeding in TKA. We evaluated 84 patients who underwent TKA and met our inclusion criteria; they were assigned to two groups: 55 controls in which a saline solution was used to wash the surgical field before tourniquet release, and a second group of 29 patients, in which a saline solution containing a low dose of norepinephrine was locally applied before tourniquet release. The local administration of a low dose of norepinephrine has induced a significant reduction of perioperative blood loss and blood transfusion requirements; in addition, this method was characterised by the absence of complications or adverse effects. In conclusion, our data suggest that intraoperative local administration of a low dose of norepinephrine could represent an effective and safe method of reducing blood loss and preventing blood transfusions in patients with TKA.

Clinical and radiographic results of ACL reconstruction: a 5- to 7-year follow-up study of outside-in versus inside-out reconstruction techniques.

This study compared the clinical outcome of anterior cruciate ligament (ACL) reconstruction between the inside-out and the outside-in techniques and assessed radiographically whether surgical technique affects the position and direction of the bone tunnels. A patellar tendon ACL reconstruction was performed in 141 patients with inside-out (group I, n = 78) and outside-in technique (group II, n = 63). Clinical results were evaluated using the International Knee Documentation Committee (IKDC) form; radiographic study was performed in anteroposterior, lateral, and notch views. Overall results in group I were normal in 23% of cases, nearly normal in 55%, and abnormal in 22%; in group II there were normal results in 19% of cases, nearly normal in 57%, abnormal in 19%, and severely abnormal in 5%. Radiographic examination identified important differences between the two groups. The main differences between the two surgical techniques were related to the positioning of the femoral tunnel. With the inside-out technique the femoral tunnel was significantly more vertical, both in the frontal and the sagittal planes. Moreover, the femoral tunnel was higher when drilled from the inside, but the difference between the two techniques was not statistically significant. The differences found between the two techniques regarding the tibial tunnel were not significant, although in the inside-out group the tibial tunnel seemed slightly more lateral, vertical, and posterior. Moreover, we observed a greater risk of bone-screw divergence on the femur in the inside-out group. This divergence was greatest in the sagittal plane. However, we observed no effect of this bone-screw divergence on the stability of the knee at follow-up.

Patellar tendon healing after removal of its central third. A morphologic evaluation in rabbits.

The central third of the patellar tendon of the right knee was removed in 40 adult New Zealand White (NZW) rabbits. The animals were divided into two groups of 20 animals each. In group 1 the tendon defect was left open and in group 2 the tendon defect was closed. The peritenon was closed in all cases. The animals were killed after 2 weeks, 1, 3, 6 and 9 months. Operated and contralateral normal tendons of each knee underwent a gross, histologic, immunohistochemical and morphometric analysis. Gross examination revealed that in the closed group there was a greater shortening of the patellar tendon but the difference between the two groups was not statistically significant. The width, thickness and cross-sectional area increased progressively in both groups and were greater in the closed group. Histological examination showed that at 1 month in both groups the harvest site was filled with a loose unoriented fibrovascular tissue. In group 1, large fatty inclusions could be seen in the deep layer, that were still present in the 3-, 6- and 9-month samples. At 3 months in group 1 the newly formed tissue was immature and rich in elastic fibres, as confirmed by immunohistochemical analysis, whereas in group 2 it was more compact and oriented. In group 1 there was in many cases an ossification on the lower pole of the patella, which was not seen in group 2. At 9 months a well-organized fibrous tissue could be seen in both groups at the harvest site. Histomorphometric analysis confirmed the better orientation and the greater density of the newly formed tissue in the closed group as compared to the open group, and the greater number of elastic fibres in the open group, even after 9 months.

Localization of collagen type IV, fibronectin and elastin in the flexor digitorum tendons and in the perichondrium during prenatal development of the human hand.

The distribution of collagen type IV, fibronectin and elastin in the flexor digitorum tendons and in the perichondrium of staged human embryos and fetal hand (from 6 to 12 weeks of gestation) has been studied to analyse the immunohistochemical features of the human hand during the first trimester of pregnancy. At 6 weeks in the transverse sections of the fingers there is no evidence of the presence of collagen type IV and elastin which remain absent even in the controls of 9, 11 and 12 weeks. On the contrary from 6 weeks of intrauterine life the fibronectin is widely distributed with thickening above all in the perichondrium and in the subjacent portion of the cartilaginous model of the bone. At 9 weeks a high positivity is detected not only along the perichondrium but even into the extra-cellular matrix of every mesenchymal cell. At 11 and 12 weeks the perichondrium is always positive but a high positivity is now present along the flexor tendons and their related sheaths that show a high grade of differentiation. To sum up, the absence of the collagen type IV into the flexor and extensor tendons is understandable because it isn't a fibrillar collagen. More difficult is to understand the absence of the elastin (component of the mature tendons) until the 12th week. On the contrary the presence of the fibronectin, a structural glycoprotein, proof of active morphogenesis of mesenchvmal cells, earlier in the perichondrium and cartilaginous sketch and later in the flexor tendons and their sheaths indicates that probably among the cells of mesenchymal origin the perichondrium with the cartilaginous model of the bone come before and perhaps orient the differentiation of the other components of the human hand.

Histogenesis and morphology of the flexor tendon pulley system in the human embryonic hand.

The number, position, structural and ultrastructural features of the flexor tendon pulley system in six human embryonic hands, aged from 6 to 12 weeks, were studied by light and electron microscope. The pulley system can be recognized from the ninth week; later, at 12 weeks, the structures are easily identified around the flexor tendon in positions closely correlated to those found during post-natal growth and in the adult hand. Structurally and ultrastructurally the pulleys are not simply thickened portions of the sheath. They are formed by three layers: an inner layer, one or two cells thick, probably representing a parietal synovial tendon sheath; a middle layer formed by collagen bundles and fibroblasts whose direction is mainly perpendicular to the underlying phalanx; and an outermost layer consisting of mesenchymal tissue with numerous vessels which extends dorsally in an identical layer, forming a ring that includes flexor and extensor tendons and the cartilaginous model of the phalanx. The pulley does not have a semicircular shape but a much more complicated one, owing to the middle layer which in part runs dorsally and in part ventrally, under the flexor tendons.

Clinical and neurophysiological abnormalities before and after reconstruction of the anterior cruciate ligament of the knee.

OBJECTIVES: We aimed to study knee proprioception and somatosensory evoked potentials (SEPs) to stimulation of the common peroneal nerve (CPN) in 7 patients with lesion of the anterior cruciate ligament (ACL) before and after ACL reconstruction. MATERIALS AND METHODS: We recorded the spinal N14 and scalp P27 potentials in 5 patients, while in the remaining 2 patients we calculated scalp SEP maps by 20 electrodes. The knee proprioception was tested by comparing the sensitivity to movement of both the knees. RESULTS: Before surgery, all patients showed decreased knee position sense and lack of the cortical P27 potential on the side of the ACL lesion. Arthroscopic reconstruction of the ligament improved neither the knee proprioception nor the somatosensory central conduction. CONCLUSION: We suggest that the loss of the knee mechanoreceptors can be followed by modifications of the central nervous system, which are not compensated by other nervous structures.

Arthroscopic treatment of malunited and nonunited avulsion fractures of the anterior tibial spine.

Ten patients, presenting with a 10 degrees to 25 degrees deficit of knee extension after an avulsion fracture of the anterior tibial spine, were arthroscopically treated with debridement and abrasion of the anterior spine. Notchplasty was also performed in five cases where there was a more severe deficit of extension. At follow-up (mean: 39.4 months) eight patients had recovered the full articular range of motion of the knee whereas two had a slight residual deficit of extension of between 3 degrees and 5 degrees. In no case was ligament stability compromised as compared with preoperative assessment.

Graft healing after anterior cruciate ligament reconstruction in rabbits.

Anterior cruciate ligament reconstruction with patellar tendon was performed in 50 rabbits (two groups of 25 animals) by the outside-in (Group I) and the inside-out (Group II) techniques. Five animals from each group were sacrificed at different times (2 weeks, 1, 3, 6, and 9 months). Histologic analysis showed that the intraarticular part of the graft was morphologically similar to a normal ligament in both groups at 9 months. In Group 1, a newly formed bone-graft junction along the tunnel walls was observed inside the femoral tunnel. At 6 months, this junction resembled a direct type junction. The old bone-tendon junction showed an early disappearance of the fibrocartilage and was differentiated as a direct junction only at 9 months. In Group 2, at the site of the old bone-tendon junction a fibrocartilaginous layer was present during the whole process of remodeling, and at 6 months this area resembled a direct junction. These observations would suggest that when the junction is placed inside the tunnel (outside-in technique) the process of remodeling is more dramatic and slower than when it is placed at the intraarticular exit of the tunnel (inside-out technique), probably because of the formation of a new bone-graft junction along the tunnel walls that partially unload the old junction.

Meniscal allografts: cryopreservation vs deep-frozen technique. An experimental study in goats.

Meniscal transplantation was performed in two groups of 15 adult goats each, using cryopreserved (group I) and deep-frozen (group II) allografts. Animals were killed at 2 weeks, 1, 3, 6 and 12 months, and a gross, histological and biochemical (water and glycosaminoglycan) evaluation of the menisci was performed. The allografts of both groups showed a normal gross appearance and had in most cases healed at the horn attachments and at the peripheral capsular tissue with a dense scar tissue and no signs of rejection. Histological analysis showed that at 2 weeks in group I the cell number was decreased compared with the controls, and the cells were mainly distributed in the superficial layers. In group II at 2 weeks, only a few cells were present at the peripheral attachment of the menisci. At 1 month in both groups, the cell repopulation can be seen extending from the peripheral area to the superficial layers. Cell proliferation and vascularization are particularly evident in both groups in the 3-month samples. At 6 months and 1 year the grafts can be seen to be completely remodelled and morphologically similar to normal menisci in both groups. Biochemical analysis showed in both groups an increase in water content and a progressive decrease in the concentration of glycosaminoglycans. At 1 year in both groups, there were moderate degenerative changes in the articular cartilage of the tibial plateau, which were more evident in the area of exposed cartilage than in that covered by the meniscus. These results suggest that there are no significant differences between the cryopreserved and deep-frozen grafts, and that even if cryopreservation makes it possible to maintain a partial cell viability in the tissue, this does not seem to improve the morphological and biochemical characteristics of the graft.

Central nervous system modifications in patients with lesion of the anterior cruciate ligament of the knee.

Patients with traumatic lesion of the anterior cruciate ligament often experience knee instability, which, recent studies suggest, is probably due to reduced knee proprioception. We studied knee proprioception and somatosensory evoked potentials (SEPs) after stimulation of the common peroneal nerve at the knee above the articular branches subserving the sensory innervation of the anterior cruciate ligament, in 19 patients with traumatic anterior cruciate ligament lesion. Ten patients showed decreased position sense of the knee, and of these, seven presented loss of cortical P27 potential while preserving lemniscal P20 and spinal N14 responses to common peroneal nerve stimulation on the side of the anterior cruciate ligament lesion. All our patients had normal SEPs to stimulation of the posterior tibial nerve at both the ankle and the knee. We suggest that in patients showing SEP abnormalities, the dysfunction of the central somatosensory conduction is located above the medial lemniscus and is limited to common peroneal nerve somatosensory pathways. Therefore, it is likely that in the seven patients showing SEP abnormalities, the loss of the knee mechanoreceptors was followed by remodelling of the CNS above the medial lemniscus. In five patients with P27 absence after common peroneal nerve stimulation, we also recorded SEPs after stimulation of the peroneal nerve at the ankle and obtained a normal cortical positive response; moreover, in our healthy subjects, cortical responses were significantly higher in amplitude after peroneal nerve than after common peroneal nerve stimulation. These findings strongly suggest that proprioceptive afferent inputs from the knee are more effective than distal afferent inputs in generating the greater part of the common peroneal nerve cortical SEPs. Since common peroneal nerve stimulation probably allows selective recording of the responses produced by the activation of the cortical representation of the knee, minor lesions with a reduction in the number of knee mechanoceptors could result in SEP changes after common peroneal nerve stimulation.

Histological analysis of the coracoacromial arch: correlation between age-related changes and rotator cuff tears.

The purpose of this study was to analyze age-related changes in the coracoacromial arch and correlate these degenerative changes with rotator cuff tears. We obtained 80 shoulders from 40 cadavers. The mean age at death was 58.4 years. We performed a gross examination of the rotator cuff and the acromion and histological examination of the coracoacromial ligament. The statistical significance of any difference for each group considered was determined by Student's t-test. The rotator cuff was normal in 66 specimens; there was an articular-side partial tear in 4 cases, a bursal-side partial tear in 6 cases, and a full-thickness tear in 4 cases. Age was correlated with increasing incidence and severity of cuff tears. We noted age-related degenerative changes in the coracoacromial ligament, degeneration of the acromial bone-ligament junction, and acromial spur formation. Anterior acromial spur was not related to the morphology of the acromion. We observed an increased incidence of bursal-side and complete cuff tears when the acromion was curved or beaked. Degenerative changes in the undersurface of the acromion were also present when the rotator cuff was normal. Bursal-side and complete cuff tears were associated with severe degenerative changes in the acromion in 100% of cases. Articular-side cuff tears were not related either to acromial morphology or degenerative changes in the coracoacromial arch. The association between cuff tears and acromial spur was more evident in the presence of a type III acromion. Our results would suggest that the incidence and severity of rotator cuff tears are correlated with aging and with the morphology of the acromion. Rotator cuff tears that involve the bursal side are often associated with changes in the coracoacromial ligament and the undersurface of the acromion. However, degenerative changes in the coracoacromial arch are always related to aging, also in the presence of a normal rotator cuff. Articular-side partial tears do not cause damage to the undersurface of the acromion.

Light and scan electron microscopic analysis of cyclops syndrome: etiopathogenic hypothesis and technical solutions.

The loss of range of motion after anterior cruciate ligament (ACL) reconstruction is one of the most common and most challenging complications of this kind of surgery. Recently, an intercondylar notch fibrous proliferation, called cyclops syndrome because of its arthroscopic appearance, has been identified as one of the specific causes of loss of extension. The incidence of cyclops syndrome is 2%-4% [17, 18], but there is still no understanding of its etiology. We speculate on the etiology and suggest some technical solutions to reduce this complication. In 180 patients submitted to arthroscopic ACL reconstruction with patellar tendon, we observed in 4 cases a fibrous nodule adherent to the neoligament that caused a loss of extension between 12 degrees and 17 degrees. In all cases, arthroscopic removal of this nodule solved completely the loss of articular motion. The nodules were subjected to light and scanning electron microscope evaluation. We observed numerous, newly formed vessels in all 4 nodules. These vessels were made up of hyperplastic and hypertrophic cells and were surrounded by bundles of disorganized fibrous tissue. No inflammatory cells or bone or cartilaginous tissue was observed. We hypothesize a microtraumatic genesis for cyclops syndrome. Repeated microtraumas expose the graft collagen fibers, which can lead to productive inflammatory process and thence to the formation of the cyclops nodule. We suggest some technical solutions to avoid graft impingement with the notch and with the tibial bone tunnel.

The effect of intra-articular ACL reconstruction on the growth plates of rabbits.

We performed intra-articular reconstruction of the anterior cruciate ligament (ACL) with the semitendinosus tendon placed in 2 mm diameter tunnels in 21 skeletally immature rabbits. The operation caused 11% damage to the physis of the femur on the frontal plane and 3% of its cross-sectional area but no alteration of growth or axial deviation of the bone resulted. In the tibia, the operation caused 12% damage to the physis in the frontal plane and 4% of the cross-sectional area. Two tibiae developed valgus deformities and one was shortened. Histological examination showed no areas of epiphysiodesis. There was no abnormality of growth-plate thickness in the two cases of tibia valga. Osseous metaplasia in the grafted tendons did not occur. The results suggest the need for careful evaluation of the percentage of damage to the growth plate before using intra-articular methods for reconstruction of the anterior cruciate ligament in adolescents.

Patellofemoral malalignment in adolescents. Computerized tomographic assessment with or without quadriceps contraction.

Twenty-seven adolescents with anterior knee pain with or without patellar instability were studied by computerized tomography to detect patellofemoral malalignment. The examination was performed with and without quadriceps contraction with the knee flexed to 15 degrees. Congruence angle, patellar tilt angle, sulcus angle, and trochlear depth were measured. This investigation showed the well-known types of patellofemoral malalignment with quadriceps relaxed (tilted, lateralized, lateralized, and titled patella) and, in 52% of cases, revealed changes in type and severity with quadriceps contraction (in 41%, lateralization and tilting were markedly more evident; in 11%, the type of malalignment changed). The results demonstrate that, in addition to assessment with quadriceps relaxed, computerized tomography with quadriceps contraction is a useful adjunct to diagnose and define the type of malalignment in particularly difficult circumstances.

Bone-ligament interaction in patellar tendon reconstruction of the ACL.

The bone-ligament junction is one of the most complex biological tissues. Its key function is distribution of mechanical loads applied to the ligament in such a way as to diminish the concentration of stresses or shearing at the interface. This paper reports an experimental assessment of the extent to which a nearly normal junction is formed following reconstruction of the anterior cruciate ligament (ACL) with patellar tendon in 20 New Zealand white rabbits sacrificed after 2-38 weeks. A histological comparison was also made with cadaver ACLs. After 5 weeks the new ligament was still separate from the tunnel wall, inflammation was no longer present, and there was no junction tissue. A thin fibrocartilage layer was observed between the bone and the ligament after 12 weeks and was thicker 6 weeks later. After 28 weeks, there was a substantial layer of fibrocartilage. The new junction was virtually "physiological" by the 38th week, with all four layers present. Many fibrocartilaginous cells were also visible between the collagen fibres. The bone-ligament insertion was almost normal. These findings indicate that tendon reconstruction results in the formation of a structure very similar to a physiological junction, and thus ensures better load distribution over a greater ligament insertion area.