No long-term tunnel enlargement following anterior cruciate ligament reconstruction using autograft hamstring tendon with dual suspensory fixation.

PURPOSE: Bone tunnel widening following anterior cruciate ligament reconstruction (ACLR) is well documented, although the aetiology and clinical significance of this phenomenon remain unclear. At mid-term follow-up, a greater prevalence of tunnel enlargement has been reported with the use of hamstring (HS) grafts. However, there are paucity of data on what happens in the longer term. The aim of this study was to assess the change in femoral and tibial tunnel dimensions 15 years after four-strand HS ACLR. METHODS: This is a retrospective review of 15 patients who underwent arthroscopic ACLR using HS autograft tendon and were followed up radiographically at 4 months, 2 years and 15 years. Suspensory fixation was used for both ends of the graft. The diameters of the bone tunnels on posteroanterior (PA) and lateral radiographs were measured using digital callipers. Repeated measures analysis of variance (ANOVA) was used to examine change in tunnel width over time. RESULTS: Radiographic tunnel width did not significantly change between 4 months and 2 years. However, a significant decrease in width was found for both the femoral and tibial tunnels between the 2- and 15-year follow-up (P < 0.01): the femoral tunnel decreased by 50% and 51% in the PA and lateral views, respectively; the tibial tunnel decreased by 77% and 91% in the PA and lateral views respectively. There was no significant correlation between femoral or tibial tunnel width and flexion and extension deficits or with side to side differences in anterior tibial laxity at 15 years. CONCLUSIONS: This radiographic follow-up study of bone tunnel widening following HS ACLR with suspensory fixation demonstrated that tunnel width did not increase beyond 4 months and in fact had decreased significantly at long-term (15 years) follow-up. There was no correlation between tunnel width changes and clinical assessment of flexion and extension deficits or with side-to-side anterior knee laxity at 15-years. LEVEL OF EVIDENCE: IV.

Post-discharge oral antimicrobial use among hospitalized patients across an integrated national healthcare network.

OBJECTIVES: Antimicrobial stewardship programmes have focused on reducing inappropriate inpatient antimicrobial prescribing, but several small studies have found a large portion of antimicrobial exposure occurs immediately after hospital discharge. In this study, we describe the prescribing of oral antimicrobials at hospital discharge across an integrated national healthcare system. At the hospital level, we also compare total inpatient antimicrobial use and post-discharge oral antimicrobial use. METHODS: This retrospective cross-sectional study used national administrative data to identify all acute-care admissions during 2014-2016 within the Veterans Health Administration (VHA). We evaluated inpatient days of therapy (DOT) and post-discharge DOT, defined as oral outpatient antimicrobials dispensed at the time of hospital discharge. At the hospital level, inpatient DOT/100 admissions were compared with post-discharge DOT/100 admissions using Spearman's rank-order correlation. RESULTS: There were 1 681 701 acute-care admissions across 122 hospitals, and 335 369 (19.9%) were prescribed an oral antimicrobial at discharge. Fluoroquinolones (38.3%) were the most common post-discharge antimicrobial. At the hospital level, median inpatient antimicrobial use was 331.3 (interquartile range (IQR) 284.9-367.9) DOT/100 admissions and median post-discharge use was 209.5 (IQR 181.5-239.6) DOT/100 admissions. Thirty-nine per cent of the total duration of antimicrobial exposure occurred after discharge. At the hospital-level, the metrics of inpatient DOT/100 admissions and post-discharge DOT/100 admissions were weakly positively correlated with rho=0.44 (p < 0.001). CONCLUSIONS: A large proportion of antimicrobial exposure among hospitalized patients occurred immediately following discharge. Antimicrobial-prescribing at hospital discharge provides an opportunity for antimicrobial stewardship. Hospital-level stewardship metrics need to include both inpatient and post-discharge antimicrobial-prescribing to provide a comprehensive assessment of hospital-associated antimicrobial use.

Focal laser ablation as clinical treatment of prostate cancer: report from a Delphi consensus project.

PURPOSE: To define the role of focal laser ablation (FLA) as clinical treatment of prostate cancer (PCa) using the Delphi consensus method. METHODS: A panel of international experts in the field of focal therapy (FT) in PCa conducted a collaborative consensus project using the Delphi method. Experts were invited to online questionnaires focusing on patient selection and treatment of PCa with FLA during four subsequent rounds. After each round, outcomes were displayed, and questionnaires were modified based on the comments provided by panelists. Results were finalized and discussed during face-to-face meetings. RESULTS: Thirty-seven experts agreed to participate, and consensus was achieved on 39/43 topics. Clinically significant PCa (csPCa) was defined as any volume Grade Group 2 [Gleason score (GS) 3+4]. Focal therapy was specified as treatment of all csPCa and can be considered primary treatment as an alternative to radical treatment in carefully selected patients. In patients with intermediate-risk PCa (GS 3+4) as well as patients with MRI-visible and biopsy-confirmed local recurrence, FLA is optimal for targeted ablation of a specific magnetic resonance imaging (MRI)-visible focus. However, FLA should not be applied to candidates for active surveillance and close follow-up is required. Suitability for FLA is based on tumor volume, location to vital structures, GS, MRI-visibility, and biopsy confirmation. CONCLUSION: Focal laser ablation is a promising technique for treatment of clinically localized PCa and should ideally be performed within approved clinical trials. So far, only few studies have reported on FLA and further validation with longer follow-up is mandatory before widespread clinical implementation is justified.

Manganese release linked to carbonate dissolution during the start-up phase of a subsurface iron removal well in Khabarovsk, Russia.

Subsurface iron removal (SIR) is a proven pre-treatment technology for removing dissolved iron and manganese from groundwater. The start-up phase of a SIR well and the proper development of the reaction zone around the well are crucial for its subsequent performance. This study evaluates the start-up phase of a SIR production well in Khabarovsk, Russia during the first 194 SIR cycles. A strong release of manganese was observed, which led to concentrations twice as high as the background value of the pristine groundwater. Regular monitoring of the production well and its three adjacent observation wells showed that iron removal began immediately after start-up and that the reaction zone was completely formed within 25 SIR cycles. Closed-bottle batch tests and a flow-through leaching test revealed that the grain size of the aquifer material and groundwater pH are the primary controls on manganese release. During infiltration phases the dissolution of manganese-bearing carbonate minerals was caused by direct oxidation by O2, whereas the low groundwater pH of 6 seemed to be responsible for the manganese release during extraction.

Retrospective study found that outpatient care for infants exposed to drugs during pregnancy was sustainable and safe.

AIM: We determined the safety, feasibility and sustainability of an outpatient model of care for infants exposed to intra-uterine drugs. METHODS: This was a retrospective chart review of 774 drug-exposed infants born between 1998 and 2016 at the Royal Hospital for Women, Sydney, Australia. RESULTS: Most (86%) of the mothers used multiple drugs, including opioids (58%). More than three-quarters (78%) of the infants were born full term at a mean gestation of 38 weeks and hospitalised for a median of seven days. This rose to 14 days if they were medicated for neonatal abstinence syndrome (NAS). Most of the NAS patients (83%) were discharged on medication, namely morphine, and the median duration of NAS treatment was 76 (interquartile range 35-120). Three medication errors occurred: two extra doses of phenobarbitone and one infant weaned off morphine faster than prescribed. No infants were rehospitalised for NAS. Four died from sudden infant death syndrome at 2.2-5.8 months after discharge and one drowned at 15 months. None were medicated at the time of death. CONCLUSION: Outpatient care for drug-exposed infants was sustainable and had low complication rates, even for those with NAS. The optimum duration of follow-up and impact on hospital costs should be examined.

Utilization of multiparametric prostate magnetic resonance imaging in clinical practice and focal therapy: report from a Delphi consensus project.

PURPOSE: To codify the use of multiparametric magnetic resonance imaging (mpMRI) for the interrogation of prostate neoplasia (PCa) in clinical practice and focal therapy (FT). METHODS: An international collaborative consensus project was undertaken using the Delphi method among experts in the field of PCa. An online questionnaire was presented in three consecutive rounds and modified each round based on the comments provided by the experts. Subsequently, a face-to-face meeting was held to discuss and finalize the consensus results. RESULTS: mpMRI should be performed in patients with prior negative biopsies if clinical suspicion remains, but not instead of the PSA test, nor as a stand-alone diagnostic tool or mpMRI-targeted biopsies only. It is not recommended to use a 1.5 Tesla MRI scanner without an endorectal or pelvic phased-array coil. mpMRI should be performed following standard biopsy-based PCa diagnosis in both the planning and follow-up of FT. If a lesion is seen, MRI-TRUS fusion biopsies should be performed for FT planning. Systematic biopsies are still required for FT planning in biopsy-naïve patients and for patients with residual PCa after FT. Standard repeat biopsies should be taken during the follow-up of FT. The final decision to perform FT should be based on histopathology. However, these consensus statements may differ for expert centers versus non-expert centers. CONCLUSIONS: The mpMRI is an important tool for characterizing and targeting PCa in clinical practice and FT. Standardization of acquisition and reading should be the main priority to guarantee consistent mpMRI quality throughout the urological community.

Do maternal opioids reduce neonatal regional brain volumes? A pilot study.

OBJECTIVE: A substantial number of children exposed to gestational opioids have neurodevelopmental, behavioral and cognitive problems. Opioids are not neuroteratogens but whether they affect the developing brain in more subtle ways (for example, volume loss) is unclear. We aimed to determine the feasibility of using magnetic resonance imaging (MRI) to assess volumetric changes in healthy opioid-exposed infants. STUDY DESIGN: Observational pilot cohort study conducted in two maternity hospitals in New South Wales, Australia. Maternal history and neonatal urine and meconium screens were obtained to confirm drug exposure. Volumetric analysis of MRI scans was performed with the ITK-snap program. RESULT: Scans for 16 infants (mean (s.d.) gestational age: 40.9 (1.5) weeks, birth weight: 3022.5 (476.6) g, head circumference (HC): 33.7 (1.5 cm)) were analyzed. Six (37.5%) infants had HC <25th percentile. Fourteen mothers used methadone, four used buprenorphine and 11 used more than one opioid (including heroin, seven). All scans were structurally normal whole brain volumes (357.4 (63.8)) and basal ganglia (14.5 (3.5)) ml were significantly smaller than population means (425.4 (4.8), 17.1 (4.4) ml, respectively) but lateral ventricular volumes (3.5 (1.8) ml) were larger than population values (2.1(1.5)) ml. CONCLUSION: Our pilot study suggests that brain volumes of opioid-exposed babies may be smaller than population means and that specific regions, for example, basal ganglia, that are involved in neurotransmission, may be particularly affected. Larger studies including correlation with neurodevelopmental outcomes are warranted to substantiate this finding.

Cannabis, the pregnant woman and her child: weeding out the myths.

To review and summarise the literature reporting on cannabis use within western communities with specific reference to patterns of use, the pharmacology of its major psychoactive compounds, including placental and fetal transfer, and the impact of maternal cannabis use on pregnancy, the newborn infant and the developing child. Review of published articles, governmental guidelines and data and book chapters. Although cannabis is one of the most widely used illegal drugs, there is limited data about the prevalence of cannabis use in pregnant women, and it is likely that reported rates of exposure are significantly underestimated. With much of the available literature focusing on the impact of other illicit drugs such as opioids and stimulants, the effects of cannabis use in pregnancy on the developing fetus remain uncertain. Current evidence indicates that cannabis use both during pregnancy and lactation, may adversely affect neurodevelopment, especially during periods of critical brain growth both in the developing fetal brain and during adolescent maturation, with impacts on neuropsychiatric, behavioural and executive functioning. These reported effects may influence future adult productivity and lifetime outcomes. Despite the widespread use of cannabis by young women, there is limited information available about the impact perinatal cannabis use on the developing fetus and child, particularly the effects of cannabis use while breast feeding. Women who are using cannabis while pregnant and breast feeding should be advised of what is known about the potential adverse effects on fetal growth and development and encouraged to either stop using or decrease their use. Long-term follow-up of exposed children is crucial as neurocognitive and behavioural problems may benefit from early intervention aimed to reduce future problems such as delinquency, depression and substance use.

An e-nose made of carbon nanotube based quantum resistive sensors for the detection of eighteen polar/nonpolar VOC biomarkers of lung cancer.

A room temperature operating electronic nose (e-nose) has been developed by the assembly of conductive polymer nanocomposite (CPC) quantum resistive sensors (QRS). The fabrication of QRS by spray layer by layer (sLbL) of CPC solutions allowed us to obtain transducers with reproducible initial properties that could be easily tailored by adjusting either the number of sprayed layers and/or the solution composition. The selectivity of QRS was varied by changing the chemical nature of the polymer matrix in which carbon nanotubes (CNTs) were dispersed in solution, i.e., poly(carbonate) (PC), poly(caprolactone) (PCL), poly(lactic acid) (PLA), poly(styrene) (PS), and poly(methyl methacrylate) (PMMA). The e-nose was then successfully used to detect several volatile organic compounds (VOCs) selected among lung cancer biomarkers: a first set of seven polar vapours (water, ethanol, methanol, acetone, propanol, isopropanol, and 2-butanone), and another set of eleven less and nonpolar vapours (chloroform, toluene, benzene, styrene, cyclohexane, o-xylene, n-propane, n-decane, 1,2,4-trimethyl benzene, isoprene, and 1-hexene). The discrimination ability of the e-nose evaluated after a 3D principal component analysis (PCA) pattern recognition treatment was proved to be very good. Moreover, the quantitativity of the transducers' chemo-resistive responses was well fitted with the Langmuir-Henry-Clustering (LHC) model for both acetone and toluene vapours in a wide range of concentrations. The QRS developed in this study appear to be very good candidates to design low cost e-noses for the anticipated diagnosis of lung cancer by VOC analysis in breath, with ppm level sensitivity (tested down to 2.5 parts per million), short response time (a couple of seconds), low consumption, and a large signal to noise ratio (SNR ≥ 10).

Amphetamines, the pregnant woman and her children: a review.

The objective of this study is to review and summarize available evidence regarding the impact of amphetamines on pregnancy, the newborn infant and the child. Amphetamines are neurostimulants and neurotoxins that are some of the most widely abused illicit drugs in the world. Users are at high risk of psychiatric co-morbidities, and evidence suggests that perinatal amphetamine exposure is associated with poor pregnancy outcomes, but data is confounded by other adverse factors associated with drug-dependency. Data sources are Government data, published articles, conference abstracts and book chapters. The global incidence of perinatal amphetamine exposure is most likely severely underestimated but acknowledged to be increasing rapidly, whereas exposure to other drugs, for example, heroin, is decreasing. Mothers known to be using amphetamines are at high risk of psychiatric co-morbidity and poorer obstetric outcomes, but their infants may escape detection, because the signs of withdrawal are usually less pronounced than opiate-exposed infants. There is little evidence of amphetamine-induced neurotoxicity and long-term neurodevelopmental impact, as data is scarce and difficult to extricate from the influence of other factors associated with children living in households where one or more parent uses drugs in terms of poverty and neglect. Perinatal amphetamine-exposure is an increasing worldwide concern, but robust research, especially for childhood outcomes, remains scarce. We suggest that exposed children may be at risk of ongoing developmental and behavioral impediment, and recommend that efforts be made to improve early detection of perinatal exposure and to increase provision of early-intervention services for affected children and their families.

Fine control of carbon nanotubes-polyelectrolyte sensors sensitivity by electrostatic layer by layer assembly (eLbL) for the detection of volatile organic compounds (VOC).

Volatile organic compounds (VOC) sensors have recently extended their field of application to medical area as they are considered as biomarkers in anticipated diagnosis of diseases such as lung cancer by breath analysis. Conductive polymer nanocomposites (CPC) have already proved their interest to fabricate sensors for the design of electronic noses (e-noses) but, for the first time to our knowledge, the present study is showing that electrostatic layer by layer assembly (eLbL) is bringing an interesting input to tailor the sensitivity of carbon nanotubes (CNT)-polyelectrolyte sensors. By this technique transducers are progressively built in 3D alternating dipping into sodium deoxycholate (DOC)-stabilized SWNT and poly(diallyldimethyl-ammonium chloride) [PDDA] solutions, respectively anionic and cationic. The precise control of transducers thicknesses (between 5 and 40nm) resulting from this process allows a fine tuning of multilayer films resistance (between 50 and 2kΩ) and thus of their sensitivity to VOC. Interestingly the surfactant used to disperse CNT into water, DOC is also found to enhance CNT sensitivity to vapors so is it for the polyelectrolyte PDDA. Finally it is found that transducers with 16 bilayers of PDDA/DOC-CNT provide optimum chemo-resistive properties for the detection and discrimination of the eight vapors studied (chloroform, acetone, ethanol, water, toluene, dichloromethane, tetrahydrofuran and methanol).

Outcome of surgery for recurrent patellar dislocation based on the distance of the tibial tuberosity to the trochlear groove.

We evaluated the outcome in a series of patients with recurrent patellar dislocation who had either medial transfer of the tibial tuberosity and lateral release or an isolated lateral release as the primary treatment. The decision to use one or other procedure was based on a pre-operative distance between the tibial tuberosity to the trochlear groove (TTTG) of less than 10 mm to include the tibial tuberosity transfer in addition to the lateral release. Between April 2002 and December 2006, 49 patients (63 knees) underwent one of these procedures. A total of 35 patients (46 knees) was evaluated at a mean of 38 months (13 to 71) post-operatively. Medial transfer of the tibial tuberosity was performed in 33 knees and isolated lateral release in the remaining 13. Evaluation included the International Knee Documentation Committee (IKDC), the Kujala and the Short-form 36 scores. From the tibial tuberosity group 23 knees also underwent radiological examination at follow-up. There were further episodes of patellar dislocation in six of the 46 knees available for review. Further dislocation was noted in five of 33 knees (15.2%) in the tibial tuberosity transfer group and in one of 13 knees (7.7%) in the lateral release group. The mean subjective IKDC score was 80.4 (sd 11.6), the mean Kujala score 88 (sd 8.2) and the mean objective IKDC score was 79% normal and 21% nearly normal. The mean post-operative TTTG distance in the tibial tuberosity transfer group was 8.9 mm (3.2 to 15.7) compared with the mean pre-operative value of 16.8 mm (12.2 to 24.4).

Fragile X mental retardation protein replacement restores hippocampal synaptic function in a mouse model of fragile X syndrome.

Fragile X syndrome (FXS) is caused by a mutation that silences the fragile X mental retardation gene (FMR1), which encodes the fragile X mental retardation protein (FMRP). To determine whether FMRP replacement can rescue phenotypic deficits in a fmr1-knockout (KO) mouse model of FXS, we constructed an adeno-associated virus-based viral vector that expresses the major central nervous system (CNS) isoform of FMRP. Using this vector, we tested whether FMRP replacement could rescue the fmr1-KO phenotype of enhanced long-term depression (LTD), a form of synaptic plasticity that may be linked to cognitive impairments associated with FXS. Extracellular excitatory postsynaptic field potentials were recorded from CA3-CA1 synaptic contacts in hippocampal slices from wild-type (WT) and fmr1-KO mice in the presence of AP-5 and anisomycin. Paired-pulse low-frequency stimulation (PP-LFS)-induced LTD is enhanced in slices obtained from fmr1 KO compared with WT mice. Analyses of hippocampal synaptic function in fmr1-KO mice that received hippocampal injections of vector showed that the PP-LFS-induced LTD was restored to WT levels. These results indicate that expression of the major CNS isoform of FMRP alone is sufficient to rescue this phenotype and suggest that post-developmental protein replacement may have the potential to improve cognitive function in FXS.

A prospective longitudinal study to assess psychological changes following anterior cruciate ligament reconstruction surgery.

OBJECTIVE: To determine whether the psychological characteristics of athletes who have undergone an anterior cruciate ligament (ACL) reconstruction change during rehabilitation are related to returning to competitive sport. DESIGN: Prospective longitudinal study. METHOD: 87 athletes completed the Emotional Response of Athletes to Injury Questionnaire (ERAIQ) and the ACL Return to Sport after Injury scale (ACL-RSI) at 3, 6 and 12 months following ACL reconstruction surgery. Physical outcome measures were also taken at each time point. RESULTS: At 12 months 44 (51%) participants had returned to competitive sport and 43 (49%) participants had not returned. There were no differences in physical recovery or scores on the ERAIQ between the two groups. Participants who had returned to competitive sport at 12 months, however, scored significantly higher on the ACL-RSI scale (reflecting a more positive psychological response about sport participation) at both 6 and 12 months than participants who had not returned to competitive sport. CONCLUSIONS: During rehabilitation there are significant psychological differences regarding sport resumption between athletes who do, and do not, resume competitive sport 12 months following ACL reconstruction. These differences occur as early as 6 months postoperatively and highlight the importance of addressing all aspects of an athlete's recovery in order to help facilitate the athlete returning to sport.

Impact of combined C1 esterase inhibitor/coagulation factor XIII or N-acetylcysteine/tirilazad mesylate administration on leucocyte adherence and cytokine release in experimental endotoxaemia.

We determined the effects of combinations of C1 esterase inhibitor (C1-INH) with factor XIII and of N-acetylcysteine (NAC) with tirilazad mesylate (TM) during lipo-polysaccharide (LPS)-induced endotoxaemia in rats. Forty Wistar rats were divided into four groups: the control (CON) group received no LPS; the LPS, C1-INH + factor XIII and NAC + TM groups received endotoxin infusions (5 mg/kg per h). After 30 min of endotoxaemia, 100 U/kg C1-INH + 50 U/kg factor XIII was administered to the C1-INH + factor XIII group, and 150 mg/kg NAC + 10 mg/kg TM was administered in the NAC + TM group. Administration of C1-INH + factor XIII and NAC + TM both resulted in reduced leucocyte adherence and reduced levels of interleukin-1beta (IL-1beta). The LPS-induced increase in IL-6 levels was amplified by both drug combinations. There was no significant effect on mesenteric plasma extravasation. In conclusion, the administration of C1-INH + factor XIII and NAC + TM reduced endothelial leucocyte adherence and IL-1beta plasma levels, but increased IL-6 levels.

Kinematic patterns associated with accuracy of the drop punt kick in Australian Football.

Research into the kinematics of movement associated with the accuracy of the drop punt kick in Australian Football has been limited. The aim of this study was to examine pelvic and lower limb kinematics during the performance of a drop punt kick, in order to identify factors associated with accurate kicking performance. Ten professional Australian Football League (AFL) players performed 20 drop punt kicks towards a target situated 15m away, using their preferred leg. A three-dimensional motion analysis system was used to record the kicking motion from heel contact of the support limb through to ball contact. The subjects were divided into an accurate group (> or =50% accuracy; n=5) and an inaccurate group (<50% accuracy; n=5) based on target hit rate. Kinematic profiles for both kicking and support limbs were compared between the two groups. Results showed that the accurate group had significantly greater hip flexion in both limbs and greater knee flexion in the support limb throughout the kicking movement. The accurate group also had significantly greater anterior pelvic tilt at heel contact (accurate 20.8 degrees ; inaccurate 12.7 degrees ). These data show that kinematic differences in lower limb joint angles may be related to kicking accuracy.

A systematic review of the effect of proprioceptive and balance exercises on people with an injured or reconstructed anterior cruciate ligament.

This systematic review investigated the effect of proprioceptive and balance exercise on outcomes following injury and surgical reconstruction of the anterior cruciate ligament (ACL). Five studies of high quality that offered empirical evidence by comparing one rehabilitation program to another were included in this review. There is some evidence that proprioceptive and balance exercise improves outcomes in individuals with ACL-deficient knees. Improvements in joint position sense, muscle strength, perceived knee joint function, and hop testing were reported following proprioceptive and balance exercise. Only one included study investigated proprioceptive exercise following ACL reconstruction. Benefits were noted in the proprioceptive group for measures of strength and proprioception; however, no benefits were noted for any measures of activity. No detrimental effects--such as increased passive joint laxity or decrease in strength--were noted when compared with standard rehabilitation programs for both ACL-deficient and ACL-reconstructed individuals. Further research is required to determine if proprioceptive and balance exercise improves long-term outcomes such as return to sport.

A randomised controlled trial of proprioceptive and balance training after surgical reconstruction of the anterior cruciate ligament.

A randomised controlled trial (29 participants) was used to compare a 6-week proprioceptive and balance exercise program with a 6-week strengthening program in the early phases of rehabilitation after anterior cruciate ligament (ACL) reconstruction. Measurements of functional activity were taken by a blinded assessor before the intervention and at the end of the 6 weeks. Results demonstrated that there were no significant differences between groups on hop testing at 6 weeks. For several items in the Cincinnati knee rating system and the patient specific functional scale however, the strengthening group improved more than the proprioceptive and balance group (p < .05). The hypothesis that proprioceptive and balance training would improve functional activity more than strengthening exercises was not supported. There was either no difference between the two forms of exercise or strength training may be more beneficial than proprioceptive and balance training in the early phase of rehabilitation after ACL reconstructive surgery.

Abnormal tenocyte morphology is more prevalent than collagen disruption in asymptomatic athletes' patellar tendons.

This study investigated the prevalence of each of the four features of patellar tendinosis in asymptomatic athletic subjects undergoing patellar tendon anterior cruciate ligament (ACL) reconstruction. Fifty subjects (39 males and 11 females) undergoing ACL reconstruction using a patellar tendon graft were screened for previous tendon symptoms, training and playing history and had their patellar tendons examined with ultrasound prior to surgery. During surgery, a small piece of proximal posterocentral tendon was harvested, fixed and examined under light microscopy. Histopathological changes were graded for severity. Results demonstrate that 18 tendons were abnormal on light microscopy and 32 were normal. There were no differences between subjects with and without pathology in respect of training, recovery after surgery and basic anthropometric measures. Three tendons were abnormal on ultrasound but only one had proximal and central changes. Tendons showed a consistent series of changes. Tenocyte changes were found in all but one of the abnormal tendons. In all but one of the tendons with increased ground substance there were tenocyte changes, and collagen separation was always associated with both tenocyte changes and increased ground substance. No tendons demonstrated neovascularization. It appears that cellular changes must be present if there is an increase in ground substance, or collagen and vascular changes. Further research is required to confirm these findings.