Heterotopic ossification within an arthroscopic portal after uneventful partial meniscectomy

We report the case of a 44-year-old man who underwent a partial medial meniscectomy for a meniscal tear whose postoperative course was complicated by the development of heterotopic ossification (HO) within the medial arthroscopic portal. Following a routine initial procedure, the patient presented with ongoing pain and a palpable, painful lump around the previous medial arthroscopy portal. Plain radiographs and MRI were suggestive of a bony structure within the soft tissues. Histopathological examination at repeat arthropscopy confirmed osseous tissue consistent with HO. Recovery after the second procedure was rapid and resulted in normal knee function and complete pain relief. HO within an arthroscopy portal is a rare complication following arthroscopic partial meniscectomy in the knee and has not previously been described in the literature.     

Outcomes at 20 years after meniscectomy in young patients

AimTo define arthroscopic meniscectomy (AM) outcomes in young patients at 20 years follow up in terms of predictors of poor clinical results, rate and timing of conversion to total knee replacement (TKR).MethodsThe following data were collected for 225 patients aged between 18 and 50 years with meniscal tear (MT) who underwent AM: age at surgery, gender, injured meniscus, knee alignment, associated lesions, amount of meniscal resection. At 20 years follow up, rate and timing of TKR conversion and clinical outcomes with Knee injury and Osteoarthritis Outcome Score (KOOS) score were reviewed.ResultsTen patients (4.4%) required TKR in the follow up period. The mean time from AM to TKR was 7.0 years (standard deviation 3.87). Age between 40 and 50 years at AM (P < 0.01), malalignment (P < 0.01), lateral meniscectomy (any size, P = 0.01), advanced chondral lesion (Outerbridge > 2, P < 0.01) and total meniscectomy (P < 0.01) were significantly related to subsequent TKR. Negative predicting factors to obtaining equal or superior to age/sex-adjusted KOOS score were age between 40 and 50 years old at time of AM (P < 0.01), female sex (P < 0.01), malalignment (P = 0.04), and advanced chondral lesion (Outerbridge > 2, P = 0.02).ConclusionsTwenty years conversion rate to TKR after AM for MT is 4.4% and TKR was performed after a mean time of 7 years. Significant association between TKR surgery and advanced chondral lesion (Outerbridge > 2), total meniscectomy, lateral meniscectomy, age at surgery between 40 and 50 years old, and malalignment were found. Age between 40 and 50 years at time of AM, female, malalignment, advanced chondral lesion were all factors significantly related to poor clinical results.     

Effect of high intensity interval training on 2,3-diphosphoglycerate at rest and after maximal exercise

Summary The purpose of this study was to examine the effect of intense interval training on erythrocyte 2,3-diphosphoglycerate (2,3-DPG) levels at rest and after maximal exercise. Eight normal men, mean ± SE=24.2±4.3 years, trained 4 days·week^–1 for a period of 8 weeks. Each training session consisted of eight maximal 30-s rides on a cycle ergometer, with 4 min active rest between rides. Prior to and after training the subjects performed a maximal 45-s ride on an isokinetic cycle ergometer at 90 rev·min^–1 and a graded leg exercise test (GLET) to exhaustion on a cycle ergometer. Blood samples were obtained from an antecubital vein before, during and after the GLET only. Training elicited significant increases in the amount of work done during the 45-s ride (P<0.05), and also in maximal oxygen uptake ( max: Pre=4.01±0.13; Post=4.29±0.07 l·min^–1;P<0.05) during exercise and total recovery (Pre=19.14±0.09; Post=21.45±0.10 l·30 min^–1;P<0.05) after the GLET. After training blood lactate was higher, base excess lower and pH lower during and following the GLET (P<0.05 for all variables). Training caused no significant differences in erythrocyte 2,3-DPG levels at rest (Pre=11.8±0.7; Post=12.1±0.7 mol·g^–1 hemoglobin (Hb);P>0.05), at exhaustion (Pre=12.0±0.8; Post=11.2±0.8 mol·g^–1 Hb;P>0.05) or during 30 min of recovery from the GLET. Additionally, acute exercise (pre-training GLET) did not effect any change in 2,3-DPG at exhaustion or during recovery from exercise compared to resting values. The higher max and total recovery values observed after training appear to be unrelated to 2,3-DPG levels. Under the present conditions, the role, if any, of 2,3-DPG in enhancing tissue oxygenation during increased metabolic demand remains obscure.Supported by grants from Miles Laboratories, Elkhart, Indiana, and the Ball State Graduate Student Research Fund     

Does functional alteration of the gonadotropic axis occur in endurance trained athletes during and after exercise?

In men, the hypothalamic-pituitary-testicular axis controls the secretion of testosterone which, in this sex, is a major anabolic hormone. Physical exercise modulates testosterone concentration, affecting the whole axis by poorly understood mechanisms. We have reported in this preliminary study the short and longterm effects of exercise on the function of the gonadotropic axis in trained compared to untrained subjects. Environmental factors known to interfere with pituitary function were minimized. Four marathon and four sedentary men, were studied during 5 days successively using different combinations of two factors: duration and intensity of running tests. Day 0 (DO) was a rest day, and the exercises were: D1 and D2 brief (20 min), light (50% maximal heart rate, HR_max, D1) or intense (80% HR_max, D2), D3 and D4 prolonged (120 min) and light (50% HR_max, D3) or intense (80% HR_max, D4). Testosterone (free and total) and luteinizing hormone (LH) concentrations were measured before, during and after exercise. The baseline concentrations of plasma testosterone were lower in the long distance runners than in the sedentary group [41.8 (SEM 5.5) vs 64.5 (SEM 7.9) pmol · 1^–1, respectively;P < 0.05]. This phenomenon was centrally mediated as LH concentration was apparentlyinappropriately low [3.4 (SEM 0.4) vs 4.3 (SEM 1.0) UI · 1^–1;P > 0.05]. Light to moderate exercise did not modify testosterone and LH concentrations. Conversely, intense and prolonged exercise increased testosterone concentration [73.2 (SEM 9.0) vs 92 (SEM 11.0) pmol · 1^–1 in the long distance runners and sedentary group, respectively;P < 0.05] and lowered LH concentrations [2.1 (SEM 0.3) vs 3.4 (SEM 0.3) UI · 1^–1 in the long distance runners and sedentary group, respectively;P <0.05 compared to DO, at the same time]. In our conditions of exercise, negative feedback of testosterone upon LH persisted, as positive feedback of low testosterone concentrations was apparently lacking (inappropriately low LH concentration with regard to low basal testosterone concentration).     

Radiographic evaluation of knee osteoarthritis in predicting outcomes after arthroscopic partial meniscectomy

BackgroundKnee osteoarthritis (OA) severity is a predictor of outcomes after arthroscopic partial meniscectomy (APM). Magnetic resonance imaging (MRI) grading of OA is predictive of postoperative outcomes; this prospective study assessed whether radiographic grading is also predictive of outcomes.MethodsPatients who underwent APM between February 2015 and January 2016, underwent radiography and MRI ≤ 6 months before surgery, and had outcomes from the surgery date and one year later were included. Surgical failure was defined as < 10-point improvement in the Knee Osteoarthritis Outcome Score pain subscore. Radiographs were evaluated using Kellgren-Lawrence (KL) grading and continuous and ordinal minimum joint space width (mJSW) measurements; cartilage loss on MRI was evaluated using a modified Outerbridge system. Predictive abilities were estimated using area under the receiver operating characteristic curve (AUC) with 95% confidence intervals (CIs).ResultsThe study cohort included 66 knees from 64 patients (32 women; mean age, 57.1 years; range, 45–77). Radiographic grading was not predictive of outcomes (KL, AUC = 0.541 [95% CI: 0.358, 0.724]; continuous mJSW, AUC = 0.482 [95% CI: 0.305, 0.659]; ordinal mJSW, AUC = 0.534 [95% CI: 0.433, 0.634]). Comparison of radiographs showing no joint space narrowing (KL grade 0–2) with corresponding MR images demonstrated that 48% of radiographs missed a clinically significant lesion (modified Outerbridge grade ≥ 3). MRI grading was predictive of outcomes (AUC = 0.720 [95% CI: 0.581, 0.859]).ConclusionsRadiographic grading of OA is not predictive of outcomes after APM; radiographs may miss clinically significant lesions. For outcome prediction, MRI should be used.     

Parathyroid hormone concentrations during and after two periods of high intensity exercise with and without an intervening recovery period

The purpose of this study was to examine the effect of a recovery period between two periods of exercise on bone metabolism and related hormones. Concentrations of serum parathyroid hormone ([PTH]), plasma ionized calcium ([Ca²⁺]) and total calcium were measured. A group of 12 healthy men aged 20–27 years participated in this study. They took part in two exercise protocols (P₁ and P₂) on two separate weeks. The exercise in P₁ comprised two successive periods of 21 min each at 70% and 85% of maximal oxygen uptake; P₂ comprised two periods of exercise at the same intensities but separated by 40 min of recovery. Venous blood samples were collected 1 day before the sessions (control), before each protocol, during (7th and 21st min), at the end (42nd min in P₁ and 82nd min in P₂) and after 24 h of recovery. The [PTH] was significantly elevated during the two protocols (P<0.01), remained raised in P₁ after 24 h of recovery (P<0.05) and was significantly lower (P<0.01) at the end of P₂ when compared to P₁. The [Ca²⁺] decreased significantly during and at the end of the two protocols (P<0.01) and had returned to control values after 24 h of recovery. Plasma lactate concentration increased during the two protocols (P<0.01) and returned to control values after recovery. These results indicate firstly that [Ca²⁺] decreases during continuous exercise as [PTH] increases and remains raised after 24 h of recovery, secondly that a recovery period between two periods of exercise attenuates the variations in [Ca²⁺] and [PTH], and thirdly that recovery may have anabolic effects on bone. However, the small physiological changes observed prevent us from forming any firm conclusion about this. Electronic Publication     

The Graz learning and training model for arthroscopic surgery

Summary Up to 30% of all operative procedures in orthopaedic surgery are performed arthroscopically. Because of the steadily increasing number of residents, it seems to be difficult both to maintain high standards and to guarantee an adequate training in arthroscopic surgery. However, in contrast to many other surgical techniques it is possible to learn and practice arthroscopy using artificial models and cadaver joints, provided that experienced surgeons and anatomists act as supervisors and instructors. The aim of this paper is to assess practice models and training programs which should guarantee sufficient practical experience during the training period.

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Modèle d'apprentissage et d'entraînement à la chirurgie sous arthroscopie

Résumé Jusqu'à 30% de toutes les techniques opératories en chirurgie orthopédique sont réalisées sous arthroscopie. En raison du nombre croissant de résidents, il semble difficile de maintenir à la fois le haut niveau de formation et de garantir un entraînement adéquat à la chirurgie sous arthroscopie. Toutefois, contrairement à de nombreuses autres techniques chirurgicales, il est possible d'apprendre à pratiquer l'arthroscopie en utilisant des modèles artificiels ou des articulations de cadavres, dans la mesure où des chirurgiens et des anatomistes expérimentés agissent comme enseignants et tuteurs. Le but de ce travail était d'évaluer les modèles pratiques et les programmes d'entraînement pouvant garantir une expérience pratique suffisante durant la période d'apprentissage.

     

The Graz learning and training model for arthroscopic surgery

Up to 30% of all operative procedures in orthopaedic surgery are performed arthroscopically. Because of the steadily increasing number of residents, it seems to be difficult both to maintain high standards and to guarantee an adequate training in arthroscopic surgery. However, in contrast to many other surgical techniques it is possible to learn and practice arthroscopy using artificial models and cadaver joints, provided that experienced surgeons and anatomists act as supervisors and instructors. The aim of this paper is to assess practice models and training programs which should guarantee sufficient practical experience during the training period.     

Renal protein excretion after exercise in man

Summary Thirteen men were submitted to graded exhaustive cycle exercise to determine the kinetics of proteinuria in the recovery period. Venous blood samples were analysed for haematocrit, lactate, creatinine, total protein and albumin for 1 h following exercise. Urine samples were collected during a 3-h recovery period. Total protein, albumin, and creatinine levels were determined for these samples. Total protein and albumin urinary excretion increased to 581 and 315 μg min⁻¹, respectively, at the end of the 1st h of recovery as compared to 42 and 15 μg · min⁻¹ for resting values. Plasma volume returned to pre-exercise levels between 30 and 60 min after cessation of exercise, while urinary total protein and albumin content still remained above the resting values for the following 2 h. Both post-exercise urinary total protein and albumin excretion followed a logarithmic decline with the same half-life of 54 min, thus requiring about 4 h to regain resting values. The reduction of plasma volume and the degree of dehydration do not seem to be involved in the process. The present study indicates the delayed recovery of protein handling by the kidney, as compared with other biochemical parameters, and provides accurate information on the kinetics of post-exercise proteinuria.     

关节镜下治疗各型膝关节脱位的中期疗效评价

目的 探讨关节镜下治疗各型膝关节脱位的可行性及中期临床疗效。方法 回顾性分析2007年2月—2012年8月收治的35例膝关节脱位患者的临床资料。按照Schenck分型：KD-Ⅱ型4例,KD-ⅢL型6例,KD-ⅢM型18例,KD-Ⅳ型2例,KD-Ⅴ型5例。根据Lysholm功能评分、Tegner评分、膝关节活动度及膝关节稳定性对手术前后患膝功能进行评估,并采用配对t检验统计分析。结果 所有患者均获随访,平均随访24.8个月（6～48个月）。末次随访时,Lysholm膝关节功能评分由术前（36.7±5.7）（0～70）分提高至（86.5±11.2）（49～100）分,Tegner膝关节运动水平评分由术前（0.8±0.6）（0～2）分提高至（5.4±1.2）（3～6）分,膝关节关节活动度由术前73.2°±15.1°（15°～125°）提高至120.1°±7.3°（90°～135°）,差异均有统计学意义（P值均〈0.05）。结论 关节镜下治疗各型膝关节脱位是治疗膝关节脱位的安全、有效方法,具体治疗策略应根据脱位分型以及膝关节损伤情况来制定。     

关节镜下松解术治疗冻结肩疗效观察

目的观察关节镜下粘连松解术治疗冻结肩的临床疗效。方法 2014年1月至2015年12月,对23例冻结肩患者,原发性18例、继发性5例,进行关节镜下粘连松解。术前、术后根据VAS疼痛评分及Constant肩关节功能评分评价治疗效果。结果 23例患者全部随访,平均随访16个月(12~30个月)。在术后1、3、12月时疼痛评分(2.5±0.95),(1.3±0.54),(1.0±0.42)分,较术前(6.5±2.31)分明显降低,肩关节功能评分(78.6±4.61),(80.6±3.99),(85.5±4.45)分,均高于术前(30.6±3.63)分,差异具有统计学意义(0.05)。结论采用关节镜下粘连松解治疗原发性及继发性冻结肩,创伤小,恢复快,疗效可靠。     

Cardiac rehabilitation: applying exercise physiology in clinical practice

In this paper new insights into the beneficial effects of physical training for patients with coronary artery disease are reviewed. Endurance training as part of a comprehensive cardiac rehabilitation programme in combination with strength training, smoking cessation and lipid management may slow down and in some cases reverse the progress of coronary atherosclerosis. Thus, exercise training remains an invaluable tool in the hands of the clinical cardiologist dealing with chronic coronary care. Accepted: 12 June 2000     

关节镜下半月板部分切除术在中老年半月板损伤治疗中的应用

目的：研究40岁以上的半月板损伤患者接受关节镜下半月板部分切除术后的临床疗效。方法：2006年1月-2008年12月,我院共有66名40岁以上患者接受了关节镜下半月板部分切除术,手术方法均为先行关节镜探查,将半月板损伤的部分切除,再将剩余的半月板保留并且修整成型。术后采用Lysholm评分系统来对患者进行疗效评价;对于60岁以上的或者是患有明确骨性关节炎的患者,采用膝关节骨性关节炎严重性指数（ISOA）评价其疗效。结果：随访时间为3．5—6a,平均随访时间为4a2个月。在各个年龄组包括骨性关节炎组,其术前、术后的Lysholm评分在统计学上都具有显著性差异（P〈0．05）;但是在60岁以上或者骨性关节炎的患者中,其术后ISOA较术前却没有明显统计学差异（P〉0．05）。结论：关节镜下半月板部分切除术对40岁以上半月板损伤的患者具有一定的疗效,但是对于60岁以上或者是已经罹患骨性关节炎的患者,行关节镜下半月板部分切除术的价值需要慎重评估。     

Satellite cell activation after muscle damage in young and adult rats

Background: Level exercise leads to focal structural damage in muscle fibers and to an increase of creatine kinase in the blood. We questioned whether it also induces activation of young and adult muscle satellite cells toward proliferation. Methods: Rats of two different ages, 6 and 16 weeks, were forced to run on a level treadmill and killed at different time intervals. The temporal profile, up to 3 weeks, of muscle damage was investigated by quantification of the focally disturbed fiber area in longitudinal sections of the m. soleus. Bromodeoxyuridine (BrdU) was injected before death to determine the labeling index of satellite cells. Labeled and unlabeled satellite cells, myonuclei, and fibers were counted in cross sections of the belly part of the muscles. Results: The muscle fiber damage differed in both amount and temporal profile between young and older animals. Damage was already visible immediately after running. However, whereas in the younger animal the amount of damage increased gradually in time until 8% at 48 hours and disappeared to almost control levels at 1 week after running, in the older animals the amount of damage was lower but remained present for at least 2 weeks. The cell kinetic data on both groups showed a proliferation response of satellite cells throughout the muscle. The effects were most pronounced in the older rats. In these rats a large increase of the labeling index was found between 24 hours and 1 week, whereas the total number of satellite cells was consistently higher from 2 days on until 2 weeks after running. In the younger animals roughly the same time pattern was observed. Conclusion: Since the damage differed in amount and time between the two age groups, we conclude that the quick and huge proliferation response is due to leakage of mitogenic factors through small membrane disruptions that are generated during the exercise itself. © 1995 Wiley-Liss, Inc.     

Comparison of changes in testosterone concentrations after strength and endurance exercise in well trained men

Summary Changes in the testosterone concentrations after single sessions of endurance and strength training were measured in seven well trained men, experienced in both forms of training. Both training sessions were rated as hard to very hard on the Borg scale. Blood samples for testosterone measurements were taken before, immediately after, and 2, 4 and 6 h after the training sessions as well as the next morning. The mean tes tosterone concentration increased 27% (P<0.02) and 37% (P< 0.02) during the strength and endurance training session, respectively. Two hours after the training sessions the mean testosterone concentration had re turned to the pre-training level and remained at that level for the length of the observation period. There were no significant differences in the changes in testosterone concentration after strength and endurance training but there were large differences in the testosterone response at the level of the individual. A high correlation (r=0.98;P<0.001) for individuals was found between increases in testosterone concentration after strength and after endurance training. It was concluded that the changes in mean testosterone values followed the same timecourse after single sessions of strength and endurance training of the same duration and perceived exertion. The interindividual differences in tes tosterone response may be of importance for individual adaptation to training.     

Exercise and Sleep Loss: Effects on Recovery Sleep

The effects of exercise and sleep loss on recovery sleep were studied in young male naval volunteers. For 1 hr out of every 4 hrs during a 40-hr period, 20 subjects rested in bed and 10 subjects bicycled. Eleven measures of recovery night sleep were selected for comparison of the bedrest and exercise groups. Only one reached significance under the conservative Dunn-Bonferroni criterion: the exercise group had a higher percent total sleep time. The results indicate that exercise does increase the effects of sleep loss on recovery sleep, but that there is no simple, direct effect on specific sleep stages.     

Exercise after heart transplantation

Exercise intolerance in heart transplant recipients (HTR) has a multifactorial origin, involving complex interactions among cardiac, neurohormonal, vascular, skeletal muscle and pulmonary abnormalities. However, the role of these abnormalities may differ as a function of time after transplantation and of many other variables. The present review is aimed at evaluating the role of cardiac, pulmonary and muscular factors in limiting maximal aerobic performance of HTR, and the benefits of chronic exercise. Whereas pulmonary function does not seem to affect gas exchange until a critical value of diffusing lung capacity is attained, cardiac and skeletal muscle function deterioration may represent relevant factors limiting maximal and submaximal aerobic performance. Cardiac function is mainly limited by chronotropic incompetence and diastolic dysfunction, whereas muscle activity seems to be limited by impaired oxygen supply as a consequence of the reduced capillary network. The latter may be due to either immunosuppressive regimen or deconditioning. Endurance and strength training may greatly improve muscle function and maximal aerobic performance of HTR, and may also reduce side effects of immunosuppressive therapy and control risk factors for cardiac allograft vasculopathy. For the above reasons exercise should be considered an important therapeutic tool in the long-term treatment of heart transplant recipients.     

Effect of exercise duration on lactate kinetics after short muscular exercise

Summary Arterial blood lactate concentrations were measured in six normal males before, during and after 3 and 6-min bicycle exercises performed at three different work rates. The lactate recovery curves were fitted to a bi-exponential time function consisting of a rapidly increasing and a slowly decreasing component, which supplied an accurate representation of the changes in lactate concentration. Variations in the parameters of this mathematical model have been studied as a function of the duration of exercise and of the work rate, showing a clear dependence on exercise duration such that increasing exercise length decreases the velocity constants of the fitted curves. In terms of the functional meaning which can be given to these constants, this result indicates that extending exercise duration from 3 to 6 min reduces the ability of the whole body to exchange and remove lactate. This effect did not qualitatively modify the one already described, which is due to increased work rates, but it shifted the ability to exchange and remove lactate towards lower values. The main conclusion of the study is that lactate kinetic data vary as a function of time during exercise. This inference must be accounted for in the interpretation of lactate data obtained during muscular exercise.     

关节镜清理术联合药物注射治疗膝关节骨性关节炎的临床疗效观察

目的探讨关节镜清理术联合关节腔内药物注射治疗膝关节骨性关节炎(KOA)的临床疗效。 方法回顾性分析2015年10月至2019年10月因KOA于北京核工业医院行关节镜清理手术治疗的60例患者。按治疗方法不同将其分为对照组(n＝30)和实验组(n＝30)。对照组采用关节镜清理术治疗,在麻醉下采用常规膝前内、外侧入路作长度约5 mm的手术切口并对患膝进行穿刺,穿刺成功后置入关节镜保护套管,注入适量灌注液使关节腔扩张充盈后置入关节镜镜头,视关节内病损情况取出游离体。冲洗关节腔,吸净关节腔内的液体后缝合加压包扎切口。实验组在关节镜清理术(同对照组)的基础上,术后即刻给予2 mL医用几丁糖+1 mL复方倍他米松注射液行关节腔内注射治疗,此后每2周关节腔内注射治疗1次,共连续治疗3次。观察记录2组患者术后6周内关节肿胀与再手术例数;比较2组患者术前、术后6周膝关节疼痛程度与膝关节功能评分,膝关节疼痛程度采用疼痛视觉模拟评分法(VAS)评定,膝关节功能活动情况依据膝关节功能Lysholm评分标准评定。比较2组患者术后6周C反应蛋白(CRP)、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)炎性指标的水平。数据采用独立样本t检验、配对样本t检验及χ²检验。 结果60例患者手术均获成功。术后6周内,对照组有1例重度、2例中度、2例轻度关节肿胀,实验组有1例中度、2例轻度关节肿胀,2组比较差异无统计学意义(χ²＝1.347,P＝0.246);术后6周内对照组9例,实验组8例再手术治疗,再手术例数比较差异无统计学意义(χ²＝1.405,P＝0.263);对照组患者术后6周VAS评分较术前显者降低,而Lysholm评分较术前显著升高,差异均有统计学意义(t＝12.385、9.173,P<0.05);实验组患者手术前后VAS评分、Lysholm评分与对照组患者变化趋势相同,差异均有统计学意义(t＝13.665、11.196,P<0.05)。术前2组患者VAS评分、Lysholm评分比较,差异均无统计学意义(t＝0.174、0.105,P>0.05);术后6周,实验组患者VAS评分[(2.47±1.13)分]低于对照组患者[(3.25±1.37)分],而Lysholm评分[(86.36±11.05)分]高于对照组患者[(73.14±12.08)分],差异均有统计学意义(t＝7.301、5.415,P<0.05)。术后6周,实验组患者CRP、IL-6、TNF-α分别为(11.13±3.36) mg/L、(2.03±0.22) ng/L、(4.92±2.56) pg/mL,均较对照组[(14.75±5.32) mg/L、(5.17±1.94) ng/L、(7.18±1.98) pg/mL)]低,差异均有统计学意义(t＝3.938、5.125、6.741,P<0.05)。 结论关节镜清理术联合医用几丁糖及复方倍他米松注射液治疗KOA可有效缓解疼痛,改善膝关节功能活动,疗效满意。