Long-term follow-up of patellar tendon grafts or hamstring tendon grafts in endoscopic ACL reconstructions

Purpose

Several studies compare the short- and long-term results of anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon-bone (BPTB) graft or double-looped semitendinosus and gracilis (DLSG) graft. However, no studies evaluate the long-term results of BPTB grafts fixed with metal interference screws and DLSG grafts fixed with the Bone Mulch Screw and the Washer Loc. This prospective randomized multicentre study has the null hypothesis that there is no difference in long-term outcome between the two procedures.

Methods

A total of 114 patients with a symptomatic ACL rupture were randomized to reconstruction with either a BPTB graft (N = 58) or a DLSG graft (N = 56). Follow-up was conducted after one, two and seven years. At the seven-year follow-up, 102 of the 114 patients (89%) were available for evaluation; however, 16 of these by telephone-interview only.

Results

Ten patients in the BPTB group and 19 patients in the DLSG group underwent additional knee surgery (P = 0.048), two and three, respectively, of these were ACL revisions (n.s.). The total flexion work was lower in the DLSG group (P = 0.001). The mean peak flexion torque and extension work, however, showed no difference between the groups. No significant differences were found between the groups regarding the Tegner activity score, the Lysholm functional score, the Knee injury and osteoarthritis outcome score (KOOS), subjective knee function, anterior knee pain or mobility. There was no significant difference in laxity between the groups on the Lachman test or the KT-1,000 maximum manual force test.

Conclusions

Both grafts and fixation methods resulted in satisfactory subjective outcome and objective stability. Both these methods can therefore be considered as suitable alternatives for ACL reconstructions.

Level of evidence

II.     

The impact of the COVID-19 pandemic on the mental health of healthcare workers: study protocol for the COVID-19 HEalth caRe wOrkErS (HEROES) study

Background

Preliminary country-specific reports suggest that the COVID-19 pandemic has a negative impact on the mental health of the healthcare workforce. In this paper, we summarize the protocol of the COVID-19 HEalth caRe wOrkErS (HEROES) study, an ongoing, global initiative, aimed to describe and track longitudinal trajectories of mental health symptoms and disorders among health care workers at different phases of the pandemic across a wide range of countries in Latin America, Europe, Africa, Middle-East, and Asia.

Methods

Participants from various settings, including primary care clinics, hospitals, nursing homes, and mental health facilities, are being enrolled. In 26 countries, we are using a similar study design with harmonized measures to capture data on COVID-19 related exposures and variables of interest during two years of follow-up. Exposures include potential stressors related to working in healthcare during the COVID-19 pandemic, as well as sociodemographic and clinical factors. Primary outcomes of interest include mental health variables such as psychological distress, depressive symptoms, and posttraumatic stress disorders. Other domains of interest include potentially mediating or moderating influences such as workplace conditions, trust in the government, and the country’s income level.

Results

As of August 2021, ~ 34,000 health workers have been recruited. A general characterization of the recruited samples by sociodemographic and workplace variables is presented. Most participating countries have identified several health facilities where they can identify denominators and attain acceptable response rates. Of the 26 countries, 22 are collecting data and 2 plan to start shortly.

Conclusions

This is one of the most extensive global studies on the mental health of healthcare workers during the COVID-19 pandemic, including a variety of countries with diverse economic realities and different levels of severity of pandemic and management. Moreover, unlike most previous studies, we included workers (clinical and non-clinical staff) in a wide range of settings.

     

Rapid absorption of sumatriptan powder and effects on glyceryl trinitrate model of headache following intranasal delivery using a novel bi‐directional device

Objectives The aim was to investigate the pharmacokinetics of intranasal sumatriptan (administered using a novel bi‐directional powder delivery device) and study its effects on quantitative electroencephalography in patients with migraine. The safety profiles of the two formulations were also compared. Methods The pharmacokinetics of intranasal sumatriptan (10 mg and 20 mg) administered using a novel breath‐actuated bi‐directional powder delivery device were compared with subcutaneous sumatriptan (6 mg), along with an investigation of their effects on the electroencephalogram (EEG) following glyceryl trinitrate (GTN) challenge in 12 patients with migraine using a randomized, three‐way cross‐over design. Key findings Following intranasal delivery, median t_max was 20 min with both doses compared with 10 min after the subcutaneous dose. Mean ± SD values for C_max were 96 ± 25, 11 ± 7 and 16 ± 6 ng/ml for subcutaneous, intranasal 10 mg and intranasal 20 mg formulations, respectively. Values for area under the curve were also lower with the intranasal doses. Intranasal and subcutaneous sumatriptan induced similar EEG changes characterized by reduced theta‐power and increased beta‐power. The majority of study participants were free of pain according to the headache severity score with all treatments from 15 min through to 8 h post‐dose. All treatments were well tolerated and there were no reports of bitter aftertaste after intranasal delivery. Sumatriptan was rapidly absorbed after intranasal administration using the new device. Using the GTN challenge, sumatriptan powder delivered intranasally at a dose of 20 mg by the new device had effects similar to those of subcutaneous sumatriptan on EEG and reported headache pain, despite much lower systemic exposure. Conclusions Administration of sumatriptan intranasally at doses of 10 mg and 20 mg by the breath actuated bi‐directional powder delivery device results in rapid absorption. Delivery to target sites beyond the nasal valve induced a similar EEG profile to subcutaneous sumatriptan 6 mg and prevented migraine attacks in patients following GTN challenge. Intranasal administration of sumatriptan powder with the breath actuated bi‐directional powder delivery device was well tolerated.     

The effect of proteolytic enzymes on the induction of heterotopic bone formation by demineralized dentin in guinea pigs

Abstract. Of a total of 80 allogenic demineralized guinea pig dentin samples, 60 were treated with collagenase or trypsin, leaving a group of 20 controls. The dentin was then either subjected to amino acid analysis and transmission electron microscopy, or implanted in the abdominal muscles of 12 male guinea pigs for four weeks. Amino acid analyses of the CH₃COOH extracts of dentin matrix proteins revealed a marked difference between the collagenase- and trypsin-treated samples, suggesting the extraction by trypsin of a non-collagenous protein or of peptides derived from such a protein. Both collagenase and trypsin reduced the ability of demineralized dentin to induce bone formation, but whereas the former resulted in enhanced resorption of the dentin implants, the trypsin-treated dentin did not. If the host mesenchymal cells need to be exposed to the inducing factor for a certain minimal length of time for induction of bone formation, enhanced resorption would hinder the induction process. While electron microscopy of control specimens exhibited collagen fibrils with distinct cross-striations, the samples exposed to collagenase treatment displayed disarranged and swollen fibrils with loss of cross-striation. Many of the collagen fibrils of the trypsin-treated dentin had, however, retained their cross-striation. The present results indicate that (he bone-inducing capacity of dentin matrix may be caused by a non-collagenous protein.     

Fracture Healing After Rigid Intramedullary Nailing in Rats

Rigid intramedullary nailing of the right tibia after osteotomy with resection of the fibula was performed on 48 male Wistar rats weighing 300-400 g. Nailing was performed with 1.4-mm nails after reaming. Nail stiffness was similar to that of intact tibias. the left leg remained unoperated as control. the animals were sacrificed after 4, 8, 12 or 16 weeks, and both tibiae were tested in a 3-point bending test. of the 35 animals with the nail in situ, nine animals showed non-union at the time of testing. At 8 weeks stiffness had reached normal values, while strength and deflection showed about half of normal values. Poor strength and small deflectability combined with near normal stiffness may be taken as evidence that Wolfs law is valid also in newly formed tissues of fracture healing; the protection given by a rigid nail makes normal strength and pliability unnecessary.     

Does nasal nitric oxide come from the sinuses?

OBJECTIVE: The purpose of this study was to assess nitric oxide (NO) output by the nose and sinuses. METHOD: In one volunteer, the osteomeatal complex and sphenoethmoidal recess were occluded to isolate the nose from the sinuses. The antrum and frontal sinus were each punctured by two catheters and irrigated with air at constant flow. Nitric oxide output and its rate of accumulation in the absence of air flow were measured in each sinus and in the adjacent nasal cavity. RESULTS: Prior to ostial occlusion, NO output in the nose was 96 nL/min. It decreased by 12% after blockage of all of the ostia. In the isolated sinuses, it was 190 nL/min (antrum) and 68 nL/min (frontal). After 5 minutes stagnation; NO concentration [NO] rose in the occluded sinuses to 24,700 nL/L in the antrum and 22,300 nL/L in the frontal sinus. In the nose, it increased to 29,000 nL/L. When the period of stagnation was prolonged in the frontal sinus, the [NO] reached a plateau. NO output and accumulation were not altered in the nose or either sinus by opening their ostia. In the antrum and frontal sinus, lidocaine reduced NO output and the rate of NO accumulation, but not in the nose. CONCLUSIONS: In this volunteer, 88% of nasal NO was derived from the nose itself. Nitric oxide exchange between the frontal sinus, antrum, and nose was negligible. In the absence of air flow, [NO] rose to a plateau in the nose and frontal sinus. Lidocaine inhibited NO output in the sinuses but not the nose.