In Vivo Mouse Intervertebral Disc Degeneration Model Based on a New Histological Classification

Although human intervertebral disc degeneration can lead to several spinal diseases, its pathogenesis remains unclear. This study aimed to create a new histological classification applicable to an in vivo mouse intervertebral disc degeneration model induced by needle puncture. One hundred six mice were operated and the L4/5 intervertebral disc was punctured with a 35- or 33-gauge needle. Micro-computed tomography scanning was performed, and the punctured region was confirmed. Evaluation was performed by using magnetic resonance imaging and histology by employing our classification scoring system. Our histological classification scores correlated well with the findings of magnetic resonance imaging and could detect degenerative progression, irrespective of the punctured region. However, the magnetic resonance imaging analysis revealed that there was no significant degenerative intervertebral disc change between the ventrally punctured and non-punctured control groups. To induce significant degeneration in the lumbar intervertebral discs, the central or dorsal region should be punctured instead of the ventral region.

Intramuscular risk at insulin injection sites--measurement of the distance from skin to muscle and rationale for shorter-length needles for subcutaneous insulin therapy

BACKGROUND

Intramuscular (IM) injection can increase insulin absorption, causing hypoglycemia. Available needle lengths today are 4-12.7 mm for pens and 6-12.7 mm for syringes. We describe the distance (D) from skin surface to muscle fascia at injection sites for subcutaneous (SC) insulin therapy and recommend needle lengths to reduce IM injection risk.

MATERIALS AND METHODS

At two locations in the United States, skin and SC fat thicknesses were measured by ultrasound at the abdomen, arm, thigh, and buttock in diverse adults (body mass index [BMI] range, approximately 19-65 kg/m²) with diabetes (n=341 with one or more paired skin and SC measurement, permitting calculation of D). The natural log of D by body site, BMI, and gender were analyzed using a mixed model to estimate IM risk.

RESULTS

D varied significantly by body site, BMI, and gender (each P<0.001), increasing with higher BMI and in women. Median D ranged from 10.9 mm (95% confidence interval, 10.3, 11.6) at the thigh to 16.9 mm (15.9, 18.1) at the buttock. Minimum D was <3 mm at the thigh and <5 mm elsewhere. When inserted 90° without pinch-up, the most commonly used needle worldwide (8 mm) has estimated IM risks of 25% and 9.7%, respectively, in the thigh and abdomen, versus 1.6% and 0.1%, respectively, with a 4 mm needle. A 45° insertion reduces, but does not eliminate, IM risk with longer needles.

CONCLUSIONS

Gender, BMI, and body site affect D; when combined with needle length and insertion angle, these factors permit detailed estimates of IM insulin injection risk. Such risk varies across sites, appears greatest at the thigh, is unnecessarily increased with 8 mm and 12.7 mm needles, and is greatly reduced with shorter-length needles and good injection technique.

[Traumas to the scrotum or penis can be caused by "ordinary objects"]

In boys, most traumas to the scrotum result from sports or straddle injuries and do typically not inflict serious injury. Due to the small size and mobility of the prepubertal testicles, testicular injuries from penetrating trauma are less common in this age group. Penetrating scrotal injury, which poses a significant threat to testicular viability, is more prevalent among adolescents and young men. We describe two unusual genital injuries; one in childhood and the other in adulthood.

Intraneural injections and regional anesthesia: the known and the unknown

Peripheral nerve injury is a rare complication of regional anesthesia. Intraneural injections were once considered harbingers of neural injury with practitioners focusing on their avoidance. With ultrasound guidance, it is now possible to visualize the difference between perineural (outside the nerve), intraneural (below the epineurium), and intrafascicular (within the perineurium) injections and to determine their association with postoperative neurological complications. We also now have a better understanding of the multifactorial nature of neurologic injury based on the nerve anatomy, site of needle insertion, bevel type, location of the needle tip, pressure achieved during injection, and underlying patient factors. Using ultrasound guidance during nerve blocks has revealed that not all intraneural injections result in injury, and its use will continue to provide insight into the mechanism of anesthetic-related nerve injury.

Broken Needle in The Cervical Spine: A Previously Unreported Complication of Xiaozendao Acupuncture Therapy

Xiaozendao (meaning "small-needle-knife," in Chinese) is a form of alternative medical instrument shaped like an acupuncture needle with a flat edge on the needle tip. It is widely used for the treatment of many different disorders in Asian countries, especially in the People's Republic of China. Its use has gained increasing popularity. To our knowledge, there are no reports of practitioners' experiences or adverse events related to "small-needle-knifed" therapy until now. We reported the first case of spinal-cord injury with delayed onset of neurologic symptoms from a broken small-needle-knife insertion into the spinal cord.

Spinal cord infarction due to a self-inflicted needle stick injury

STUDY DESIGN

Case report.

OBJECTIVE

To report a case of spinal cord infarction after a self-inflicted needle stick injury, following an injection of heroin into the cord.

SETTING

National spinal injury unit in a Scottish University teaching hospital, Glasgow, UK.

CASE REPORT

A 20-year-old male, injected street heroin accidentally into the cord through the left side of the neck, leading to sudden loss of power to all four limbs. Initial magnetic resonance imaging scans showed extensive cord oedema and follow-up scans showed signal changes within the anterior horns of the spinal cord in keeping with a cord infarct.

CONCLUSION

Self-inflicted spinal cord injury with a small needle is difficult, but not impossible. Cord infarct as a result of a self-inflicted injury has not been previously reported. The mechanism of the injury resulting in cord infarction is explained by the vascular anatomy of the spinal cord circulation, and this may also explain the residual neurological status of the patient.

Inadvertent ocular perforation and intravitreal injection of an anesthetic agent during retrobulbar injection

We report the clinical management of a patient who sustained scleral perforation and intraocular injection of local anesthetic agent during retrobulbar block. We discuss the management options for this rare complication of local anesthesia in cataract surgery.

An unusual case of recurrent septicaemia

A52-year-old farmer presented with a 1-week history of fever, rigors and myalgia. Three days before admission he had developed pleuritic left-sided chest pain. Clinical examination revealed a temperature of 38.4°C and bibasal pulmonary crepitations. Chest radiograph showed an area of patchy pulmonary opacity at the left lung base and a few small areas of opacity in the right lung. A presumptive diagnosis of pneumonia was made. Blood cultures subsequently grew Staphylococcus aureus and treatment with intravenous flucloxacillin was commenced. No other focus of infection was found, investigations included normal transthoracic echocardiogram and abdominal ultrasound scan.

The patient rapidly improved; however, 2weeks later he again became febrile. Further blood cultures grew Klebsiella pneumoniae. An abdominal computed tomography scan showed a high density linear structure straddling the second part of the duodenum and the inferior vena cava, representing a foreign body (Figure 1). Clot could be seen in the vena cava where it had been penetrated. Multiple ill-defined opacities seen in the lung base were consistent with embolization of the lungs. A plain abdominal radiograph showed the foreign body was a 4cm sewing needle (Figure 2). The needle and clot were removed surgically through an incision in the inferior vena cava and culture of specimens yielded both Staphylococcus aureus and Klebsiella pneumoniae (Figure 3) . The patient was treated with cefuroxime and made an uneventful recovery but had no recollection of having swallowed the needle.

Traumatic intramuscular orbital haemorrhage

Retrobulbar haemorrhage is an uncommon but well-documented complication of retrobulbar anaesthetic blocks in ocular surgery. Peribulbar anaesthesia has been advocated to be equally effective but safer. The incidence of retrobulbar haemorrhage with peribulbar blocks is very low. We report a case in which a peribulbar anaesthetic for cataract surgery resulted in sight-threatening retrobulbar haemorrhage within the medial rectus muscle and required an anterior orbitotomy and direct decompression of the muscle. The surgery was successful. This case illustrates a potentially serious complication of peribulbar anaesthesia, with the successful outcome achieved by rapid definitive diagnosis and intervention.

Accidental injuries by HIV-contaminated instruments in health provider or research environments: can seroconversion be prevented?

The rate of seroconversion from percutaneous needlestick exposure to HIV infection is approximately 0.3 per cent. To investigate the possibility of local confinement of HIV, 100 to 200 nm Tc-99m sulfur colloid particles were injected in the canine model subcutaneously at the knee level and collected proximally at the groin from the cannulated femoral vein and lymphatic channel. Tourniquet compression (250 mm Hg) was used as an intervention to possibly restrict particle spread. It was found that particles arrived in the blood at 2.81 +/- 0.54 minutes, with later arrival in the lymph at 6.0 +/- 1.47 minutes. Tourniquet application delayed the appearance of the particulate matter in the blood up to 7.11 +/- 1.5 minutes and in lymph up to 40.0 +/- 5.10 minutes. The concentration of radioactivity in the lymph was higher than in the venous blood. The distribution of the particles reflected by flux was comparable in both pathways. The accumulation curves did not reach plateaus during 45 minutes in lymph and 15 minutes in blood. Radioactive scanning revealed that about 90 per cent of the injected particles remained locally with gradual release for at least 45 minutes. Our results suggest that HIV, introduced by needlestick injury, can be contained for possible viricidal treatment if the response includes rapid immobilization and tourniquet of the area.

Needle entrance into the maxillary sinus during retrobulbar anesthesia

Three patients are presented to whom an accidental needle entrance into the maxillary sinus occurred during retrobulbar anesthesia. In all cases air was aspirated during the aspiration check at the end of needle advancement, and the patients reported a bitter taste after the injection of a small quantity of anesthetic. After withdrawal and careful reinsertion of the needle, maxillary sinus entrance was avoided and a successful retrobulbar block was achieved. Two of the patients had no history of previous facial trauma or surgery, whereas the third had suffered a recent blowout fracture of the orbital floor. The authors suggest that air aspiration or anesthetic passage into the pharynx during retrobulbar anesthesia should raise the suspicion of maxillary sinus entrance, even in patients without any history of facial trauma or surgery. The early recognition of sinus entrance can prevent retrobulbar block failure and reinjection of a second anesthetic dose.

Bilateral mycotic axillary artery false aneurysms in an intravenous drug user: unsuspected broken needle-tips pose a risk to the treating personnel

Mycotic false aneurysms due to local arterial injury from attempted intravenous injections in drug addicts are increasing in frequency. The high incidence of HIV and hepatitis B virus in parenteral drug users may present a considerable risk to the treating personnel. This paper reports the unsuspected presence of broken needle-tips in the subcutaneous tissues of an intravenous drug abuser, in association with bilateral mycotic aneurysms of the axillary arteries. Broken needle-tips have the potential to cause needlestick injury to the operating team and the nursing staff, with the associated risk of transmission of HIV and hepatitis B virus infection. The presence of broken needle-tips should be suspected in drug users presenting with false aneurysms associated with local arterial injection injury and a specific history of needle-breakage should be sought. Preoperative plain radiographs should be performed of the planned operative field to exclude the presence of such needle-tips. Any soft tissue swelling in the vicinity of a major artery in an intravenous drug abuser should be suspected of being a false aneurysm until proven otherwise and should prompt immediate referral to a vascular surgeon for investigation and management.

[Cervical spinal cord injury caused by a broken acupuncture needle: a case report]

Spinal cord injury is a rare but considerable complication of acupuncture. A case with cervical spinal cord injury caused by a broken acupuncture needle was reported and sixteen previously reported cases including our case were reviewed. A 49-year-old woman was treated by herself with acupuncture on the nuchal region for occipitalgia, and the needle was accidentally broken during the treatment. Six hours later she noticed pain and numbness in the right upper and lower extremities. Neurological examination revealed slight impairment of temperature, pain and touch sensation on the right extremities. Plain X-ray film and CT scan showed a broken needle in the interspinous ligament between C1/C2 vertebrae, the tip of the needle appearing to be in the spinal canal. The needle was removed surgically nineteen days after the accident. Intraoperative fluoroscopic monitoring with injection of dye enabled the needle to be found without difficulty. Postoperative course was uneventful, and her pain and sensory impairment gradually disappeared. Once the diagnosis for cervical spinal cord injury by an acupuncture needle is made, the needle should be removed surgically as soon as possible, especially prior to the development of motor symptoms. This is because movement of the needle in the spinal cord is considered to be a main possible cause of the development and progression of symptoms.