Anterolateral knee pain related to thrombosed lateral patellar retinaculum veins: Unusual anterolateral pain of the knee.

We describe the ultrasound (US) features of venous thrombosis involving the lateral patellar retinaculum (LPR) veins presenting as anterolateral knee pain. Four male patients, aged 16 to 35 years, were referred for lateropatellar pain with focal tenderness. In two cases, physical examination also demonstrated soft tissue swelling at the anterolateral aspect of the knee. In all four cases, US showed subcutaneous fat edema surrounding a thrombosis involving the LPR veins. Magnetic resonance imaging performed before US in one patient revealed only nonspecific subcutaneous fat edema and was therefore unable to make the correct diagnosis of LPR venous thrombosis.

Anatomy of the middle rectal artery: a review of the historical literature.

The middle rectal artery is a very important anatomical structure in rectal cancer surgery. It is the only vessel that penetrates through the proper rectal fascia into the pelvic cavity, and therefore threatens the integrity of total mesorectal excision. Moreover, it is very closely related to the lateral lymphatic drainage root. The definition of the middle rectal artery is ambiguous, and different frequencies, origins, and trajectories have been reported in various papers. The frequency of the middle rectal artery is reported to range from 12 to 97 %. Traditionally, the middle rectal artery is described as an artery that penetrates the pelvic plexus from the lateral side along with the lateral ligament; the frequency of this lateral type of middle rectal artery ranges from 20 to 30 %. However, the reports that describe higher frequency values also consider another type of middle rectal artery, which penetrates the neuro-vascular bundle from the antero-lateral direction; this antero-lateral type of middle rectal artery tends to be a small vessel, and frequently forms a common trunk with the prostatic artery. With advancements in endoscopic surgery, the knowledge of the precise anatomy of this structure is becoming more crucial for optimal rectal cancer surgery.

Primed Mesenchymal Stem Cells Alter and Improve Rat Medial Collateral Ligament Healing.

Cell therapy with mesenchymal stem cells (MSCs) can improve tissue healing. It is possible, however, that priming MSCs prior to implantation can further enhance their therapeutic benefit. This study was then performed to test whether priming MSCs to be more anti-inflammatory would enhance healing in a rat ligament model, i.e. a medial collateral ligament (MCL). MSCs were primed for 48 h using polyinosinic acid and polycytidylic acid (Poly (I:C)) at a concentration of 1 µg/ml. Rat MCLs were surgically transected and administered 1 × 10(6) cells in a carrier solution at the time of injury. A series of healing metrics were analyzed at days 4 and 14 post-injury in the ligaments that received primed MSCs, unprimed MSCs, or no cells (controls). Applying primed MSCs beneficially altered healing by affecting endothelialization, type 2 macrophage presence, apoptosis, procollagen 1α, and IL-1Ra levels. When analyzing MSC localization, both primed and unprimed MSCs co-localized with endothelial cells and pericytes suggesting a supportive role in angiogenesis. Priming MSCs prior to implantation altered key ligament healing events, resulted in a more anti-inflammatory environment, and improved healing.

Anatomical study of fibrous structures of the medial aspect of the canine elbow joint.

Forces exerted by fibrous structures on the medial aspect of the canine elbow joint have been reported to be involved in elbow pathology. The purpose of this paper is to assess the relationships of the ligamentous and muscular structures of this region of the canine elbow joint, and how they relate to the medial coronoid process. Six cadavers of adult German shepherd cross-breed dogs were used in this study to make intra-articular and vascular injections of this region. Some joints were dissected and some were frozen to saw sagittal or dorsal cryosections to assess the relationships of the myotendinous structures. The brachialis muscle tendon passed through the division of the bicipital tendon of insertion which formed a fibrous tendon sheath that was reinforced by the oblique ligament. The biceps' brachii's main insertion is the radial tuberosity where it inserts along with the cranial branch of the oblique ligament and the cranial branch of the medial collateral ligament. Rotational and compression forces exerted by the insertion of the biceps brachii-brachialis tendon complex onto the ulna might influence medial coronoid disease. Therefore, sectioning these tendons could be considered as a treatment for medial coronoid disease.

An anatomic comparison of venous damage resulting from 2 dorsal surgical approaches to proximal interphalangeal joint arthroplasty.

Proximal interphalangeal joint arthroplasties were performed on 40 toes of 10 fresh-frozen cadaveric feet. Twenty toes had a transverse elliptical incision of skin and extensor mechanism, and 20 had a longitudinal incision with transverse excision of extensor mechanism. Venous anatomy, including damage to the dorsal collateral veins, was noted. In the transverse-incision group, 14 (70%) of 20 toes had 1 dorsal vein transected, and 2 (10%) of 20 toes had both dorsal veins transected; in the longitudinal-incision group, no dorsal collateral veins were injured. As transverse incisions carry a high risk for damaging the dorsal collateral veins, and such damage may contribute to postoperative swelling, care should be taken to protect these veins. Longitudinal incisions are less likely to damage these venous structures.

Quantitative evaluation of nutritional pathways for the posterior cruciate ligament and the lateral collateral ligament in rabbits.

The cruciate ligament of the knee receives its nutrition from a direct vascular supply and by permeation of nutrients from the synovial fluid. The contributions of these two routes as nutritional pathways are not known in detail. In this study, we injected [3H]methyl glucose as a tracer intravenously or directly into the knee of rabbits. Tracer concentrations in plasma, synovial fluid, the posterior cruciate ligament (PCL), and the lateral collateral ligament (LCL) were analysed by a pharmacokinetic compartment model. The contribution of [3H]methyl glucose permeation from the synovial fluid during steady state was calculated at 44.3% in the PCL and at 39.0% in the LCL. Although these results indicated that more than half the nutrition for both ligaments is provided by its vascular supply, synovial fluid permeation is also an important transport route for small molecules for the PCL and the LCL, which is an extra-articular structure.

Microarterial anatomy of the lesser toe proximal interphalangeal joints.

Successful free tissue transfer requires detailed knowledge of the pertinent microvascular anatomy of the donor site. The lesser toe proximal interphalangeal joints are a source of vascularized autologous tissue. In 20 adult cadaver feet, the arterial anatomy of the second, third, and fourth toes was studied using colored latex and India ink injection. The second, third, and fourth dorsal metatarsal arteries produced small or absent dorsal digital arteries in 72.5% of distal dissections. The proper digital arteries were 0.93 to 1.37 cm in length. An additional 2.3 to 2.83 cm of length can be gained by use of the plantar metatarsal arteries if the dorsal metatarsal or dorsal digital arteries are inadequate. The diameter of the medial proper digital arteries (range, 1.2-1.26 mm) was larger than the lateral proper digital arteries (range, 0.66-0.99 mm). The proper digital arteries of the lesser toes provide the predominant arterial supply of the proximal interphalangeal joints through a system of transverse and longitudinal arches.

Spatial variation in sympathetic influences on the vasculature of the synovium and medial collateral ligament of the rabbit knee joint.

1. Laser Doppler perfusion imaging was used to assess the role of the sympathetic nervous system in the control of blood flow to the medial collateral ligament and capsule (synovium and overlying fibrous tissues) of the rabbit knee joint. 2. Electrical stimulation of the saphenous nerve (width 1 ms; amplitude 20V; 1-30 Hz) produced a frequency-dependent vasoconstriction of knee joint vasculature. The response was maximal at 30 Hz and gave the greatest fall in perfusion at the femoral insertion of the ligament (by 33.8 +/- 7.4%, mean +/- S.E.M.; n = 5-6) and the smallest decrease at the tibial insertion of the ligament (by 10.6 +/- 2.9%). 3. Topical application of phentolamine (10(-6) mol) had no significant effect on basal knee joint blood flow. However, it abolished the nerve-mediated constrictor responses in all regions of the medial collateral ligament and synovium at all frequencies. 4. Topical administration of adrenaline (10(-14) to 10(-7) mol) caused a dose-dependent decrease in knee joint blood flow with the highest dose producing > 75% reduction in perfusion at all areas. 5. There was no evidence of a reactive hyperaemia in the 5 min following a 5 min period of femoral artery occlusion. Artificial manipulation of arterial blood pressure by intravenous infusion or withdrawal of blood caused a proportional change in ligament and synovial blood flow. These observations may indicate a lack of autoregulation in the joint and its exclusion from baroreflex modulation. 6. These results suggest a potential role for the sympathetic nervous system in the control of knee joint blood flow. Neuromodulation of ligament perfusion appears to predominate at the femoral insertion and this could prove to have functional significance.

The fibular collateral ligament-biceps femoris bursa. An anatomic study.

The anatomy of the fibular collateral ligament-biceps femoris bursa is described. The bursa is located lateral to the distal quarter of the fibular collateral ligament and forms an inverted "J" shape around the anterior and anteromedial portions of the ligament. Its most distal margin is just proximal to the fibular head where the fibular collateral ligament inserts, and its more proximal aspect is at the superior edge of the anterior arm of the long head of the biceps femoris muscle. We found this structure in all 50 knees dissected; there was a constant anatomic location of the fibular collateral ligament-biceps femoris bursa in all specimens. Measurement of the anatomic dimensions of the bursa revealed a mean width of 8.4 mm and a mean height of 18 mm. Knowing the prevalence, shape, size, and anatomic location of this bursa may aid the clinician in the differential diagnosis of lateral knee pain.