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Postoperative drain blood was collected and reinfused using the ConstaVac system (Stryker, Kalamazoo, MI) in 30 patients after total knee arthroplasty. Of the total 1.1-L volume of postoperative bleeding, 60% was reinfused. No clinical complications were observed. Differences between venous blood and drain blood and between venous blood and drain blood after separate incubation were studied with respect to acidic and inflammatory effects on blood cells, plasma chemistry, and whole blood rheology. In drain blood, leukocyte and platelet counts were reduced (P < .001), probably as a result of consumption in the wound. Acidic incubation occurs in the drain container because of production of lactate from glucose, with a minimum pH at 5 hours of 7.2. The low pH caused slight but significant erythrocyte swelling (P < .01). The complement C3d indicated leukocyte activation, although of modest magnitude. Despite incubation and complement activation, maximum erythrocyte hemolysis after 24 hours of incubation was less than 1%. Drain blood showed a lower resistance against micropore filtration than venous blood (P < .001), mainly because of the reduced number of leukocytes, and remained unchanged with incubation. Although the autotransfusion system can be improved with respect to blood quality, filtered drain blood should be considered acceptable for reinfusion.

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Shoulder function was assessed in 37 patients with a mean age of 57 years after acromioplasty and repair of full-thickness rotator cuff tears were performed. The cuff tears were closed without transfer of other muscles or use of synthetic materials. At review 2 years after surgery 32 patients had significant pain relief and improved shoulder function. Range of motion, muscle strength, and endurance were increased. The mean Constant score was 77, and 80% of the patients were graded as having mild or disability. Radiographic measurements disclosed an increased supraspinatus outlet area after surgery. It is concluded that in patients with impingement syndrome and a full-thickness rotator cuff tear, shoulder function will be improved after acromioplasty and cuff repair, but a slight decrease in range of motion and muscle strength will remain when compared with the contralateral side.

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Evaluation of potential new treatment strategies requires adequate experimental tumor models which resemble the clinical situation as closely as possible. The purpose of the present study was to establish a new human osteosarcoma spontaneous metastasis model using orthotopic transplantation of histologically intact tumor tissue into the tibia of nude mice. Intact tumor pieces, obtained from the 32nd serial passage of subcutaneously growing human osteosarcoma xenografts, were implanted into the proximal tibia in 31 nude mice. Animals were sacrificed and autopsied 2, 4, 6, and 8 weeks after transplantation and examined macroscopically and microscopically for local tumor growth and metastases. All mice developed local intratibial bone tumors that were radiographically and histologically similar to primary human osteosarcoma. Lung metastases were observed in all mice, local and distant lymph node metastases in 15 (48%), and liver metastases in 6 (19%) mice. The microscopic appearance of the metastases was similar to that observed in the donor patient's tumor, corresponding subcutaneous xenografts and orthotopically transplanted intratibial tumors. This spontaneous metastasis model of human osteosarcoma in nude mice may resemble a clinical situation and could thus be useful for studies on local tumor growth, metastasis formation and therapy.

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Muscle biopsies from the anterior and medial parts of the deltoid of 11 male patients and six male controls were analysed with morphological and immunohistochemical methods. The distribution, area, and capillarization of the muscle fibres were determined, and the amount of connective tissue was measured with staining for type-III collagen. Compared with the controls, the patients with impingement syndrome had more type-I than type-II fibres, but the areas of the different types were almost the same. There was no difference in capillarization per fibre type between patients and controls, but the patients had more connective tissue. The results indicate that patients with impingement syndrome have morphological changes in the deltoid muscle, probably due to immobilisation and pain. They support the hypothesis that the deltoid muscle, the medial part in particular, is affected in patients with impingement syndrome.

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Tumour specimens from one patient with osteosarcoma and one with malignant fibrous histiocytoma were transplanted in serial passages in nude mice. Structure, growth and cell kinetics of the xenografts were studied in order to assess the validity of the two tumour models. Cell proliferation was analysed using in vivo labelling with the thymidine analogue iododeoxyuridine (IdUrd) and the IdUrd labelling index (LI) was determined by immunohistochemistry. The DNA index (DI) was examined by flow cytometry. The c-myc oncoprotein expression was studied by immunohistochemistry. More intense proliferation was observed in the peripheral parts of the tumours. There was no correlation between tumour growth and cell proliferation in the two tumour groups. Stability of the tumour models was indicated by low intrapassage and interpassage variations of DI, LI, and volume doubling time, and also by retained histopathological characteristics and c-myc staining patterns of donor patients' tumours during serial transplantation.

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Amphotericin B (AmB), a polyene antifungal antibiotic, has been shown to potentiate the cytotoxic effect of different chemotherapeutic drugs in vivo and in vitro. The purpose of this study was to determine whether AmB could enhance the carboplatin antitumor activity in a human osteosarcoma xenograft model. Nude mice, bearing s.c. transplanted osteosarcoma xenografts, received i.p. an injection of AmB (5 mg/kg) 6 h prior to carboplatin (20 mg/kg) or each of the drugs separately. The effect of treatment was assessed by analyzing tumor growth delay and T/C ratio. Carboplatin clearly reduced tumor growth when administered alone. However, an unexpected interaction was seen where AmB significantly decreased the antitumor effect of carboplatin. The present results contradict some earlier in vitro studies and indicate the complexity of this interaction in vivo. Hence, it seems that interactive phenomena in one experimental model, and especially with regard to AmB, cannot be universally applied to all experimental situations.

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A human osteoblastic osteosarcoma was transplanted in nude mice and followed in seven serial passages. Tumor cell kinetics was analyzed by in vivo labelling with the thymidine analogue iododeoxyuridine (IdUrd). Immunohistochemistry was used to measure the IdUrd labelling index. Duration of S phase (ts) was estimated by flow cytometry. From these two parameters potential doubling time (tpot) was calculated. Cell kinetic parameters showed low variations between passages and also between xenografts in same passage. Smaller variations of ts compared to labelling index and tpot were found. tpot was generally short with an interpassageal mean of 1.3 days and CV=14.8%. All xenografts showed DNA aneuploidy (mean DNA index --1.6). Homogeneous tumor growth was indicated by low variations of volume doubling time and lag time. There was no correlation between tumor growth and cell proliferation. Histopathological characteristics of the donor patients tumor were retained during serial transplantation.

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A reduced retroversion angle of the humeral head may predispose to recurrent anterior shoulder dislocation and may also be a factor in persistent instability after soft-tissue repair. We performed rotational osteotomy of the proximal humerus in 20 patients with recurrent anterior shoulder dislocations (10 traumatic, 10 non-traumatic) and a decreased retroversion angle of the humeral head. The mean preoperative retroversion angle was 12 degrees, which was increased after surgery to a mean value of 32 degrees. All patients regained a normal range of shoulder motion and normal function within three months after surgery. At the five-year review all shoulders were stable, pain-free and had no radiological signs of osteoarthritis.

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It is difficult to predict the outcome of comminuted fractures of the proximal humerus and give guidelines for optimal treatment. Different treatment modalities are available, and there are various scoring systems for postoperative evaluation. The aim of this study was to assess the functional outcome after three- and four-part fractures of the humeral head in 38 patients, with a 3-year follow-up. Twenty-eight patients were treated conservatively, seven were operated on with open reduction and internal fixation, and three received a hemiarthroplasty. All patients were examined clinically and radiographically. Neer and Constant scoring systems were used. The functional outcome after three-part fractures was generally good. Twenty-five of 26 patients with a three-part fracture could accept their shoulder situation. Range of motion was significantly lower in the four-part fracture group. Mean flexion was 89 degrees compared with 120 degrees in the three-part fracture group. Necrosis of the humeral head was found in 2 cases, both four-part fractures. Osteoarthrosis developed in 13 cases (6 with a three-part fracture, 7 with a four-part fracture). No disability was found in 16 of 24 patients with three-part fractures, and in 4 of 11 patients with four-part fractures. There was strong agreement between the Constant score and the patients' opinions.

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We used the ConstaVac drainage retransfusion system in 32 patients operated on with cemented tricompartmental knee arthroplasty. The mean total postoperative bleeding was 1.1 L of which 0.7 L was retransfused within 8 hours postoperatively. Samples were taken from the venous blood and drain blood at 2 hours and 6-8 hours postoperatively. The drain blood had low counts for leukocytes and thrombocytes as compared to venous blood, and fibrinogen was almost absent. Incubation at room temperature slightly lowered glucose and pH which made the erythrocytes swell. There was a slight hemolysis in the drain blood at 2 hours. At 6-8 hours the shed blood was closer to normal, especially with regard to hemolysis, but there was a further decrease in glucose. Within this time, there was no change in acidity and no further swelling of the erythrocytes. No clinical adverse reactions were observed and we consider the observed cellular and chemical changes to be of little importance. The quality of filtered drain blood within the analyzed time limit is considered acceptable for clinical use.

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The purpose of the present study was to investigate shoulder muscle activity during eccentric muscle movements, and to determine whether electromyograms in patients with joint laxity differed from those in normal subjects. Five normal subjects and 6 patients with generalized joint laxity and shoulder instability were studied. Both shoulders were investigated. Normalized electromyograms were recorded during eccentric loaded movements from 8 shoulder muscles in parallel. Intra-muscular fine wire electrodes were used for 3 muscles of the rotator cuff: subscapularis, supraspinatus, and infraspinatus. Surface electrodes were used for superficially located muscles: the anterior, middle, and posterior parts of the deltoid, pectoralis major, and latissimus dorsi. A general trend was an activation of several muscles rather than a single muscle during all movements investigated. Patients with generalized joint laxity activated their supraspinatus and subscapularis muscles to a higher level during flexion and adduction movements than normal subjects did. This might indicate a greater necessity for muscular activity to provide anterior shoulder stability in lax joints. Compared with concentric movements previously studied, results from this study showed that the magnitude of activation was significantly lower during eccentric movements in normal subjects and in patients with joint laxity.

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Fifteen patients with primary classical osteosarcoma tumours are presented, all of whom have been operated on with local en bloc resection of the tumour mass in combination with adjuvant treatment with human leucocyte interferon. All patients have at present been followed up for more than fifteen years and half of them have shown no tumour recurrence. One patient committed suicide and eight died of generalized tumour disease. Two patients developed lung metastases five and eight years after primary surgery. This form of treatment, allowing limb preservation, is presented as an alternative to conventional ablative surgery providing that it is reserved for centres with specialized surgical teams.

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The correlation between the shift measured on bone surface in rotatory osteotomy and the radiologic change of the retroversion angle was analyzed. The humeral head retroversion was measured radiographically in 7 isolated humeri by means of a semiaxial projection. All bones were then osteotomized and the humeral head rotated in order to increase and decrease the retroversion. The retroversion was measured radiographically for each new rotational position of the head. The relationship between the measured shift in rotatory osteotomy and the change of retroversion was found to be linear. Twelve patients with recurrent anterior shoulder joint dislocations and a small humeral head retroversion were operated on in order to increase the retroversion. In all patients the increase of retroversion angle was smaller (57%) than expected on the basis of the shift in osteotomy and humeral diameter. The mean increase of retroversion was 2 degrees/mm shift (range 1.3-3.0 degrees/mm).

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The purpose of this study was to investigate the relationship between clinical symptoms, static radiographic measurements, and of load distribution during walking at the knee, in 54 patients with moderate medial osteoarthrosis of the knee. Varus deformity of the knee was assessed from static radiographic measurements as the Hip-Knee-Ankle (HKA) angle, and range of moments at the knee in the frontal plane were assessed using a Kistler force plate system. No correlations between clinical symptoms and radiographic parameters or moments at the knee were found. The adduction moment in mid stance was more important than the peak adduction moment in differentiating between patients and normal controls. The amplitude of the peak adduction moment depended on the sex and body mass of the patients, while the amplitude of the mid stance adduction moment depended on body mass and the varus deformity of the knee. There was a weak correlation between the peak adduction moment and the HKA-angle (r = 0.32, P < 0.05) and there was a moderately high correlation between the peak adduction moment in mid stance, i.e 50% of the stance phase, and the HKA angle (r = 0.46, P < 0.001) even after normalization of the mid stance moment to body mass. Accordingly, 20% of the medio-lateral knee load in mid stance during walking could be explained by the varus deformity of the osteoarthrotic knee in our patients.

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The influence of several clinical and radiographic parameters on the functional outcome of 92 patients with trochanteric hip fractures treated at random with either Ender nails or a sliding screw plate (SSP) was prospectively investigated. Apart from other clinical variables such as pain, the use of walking aids, and walking distance, the walking ability of patients was assessed by gait analysis performed on an electronic walkway. The parameters investigated were the maximal vertical force (MVF) and single-limb support phase (SLS). Independent of the type of fixation, no differences were observed between stable and unstable fractures in any of the parameters analyzed six months after surgery. In fractures treated with Ender nails, the use of walking aids and MVF were influenced by a satisfactory fracture reduction. Walking distance was the sole factor correlated with the status of fracture healing. In fractures treated with SSP, the pain was the only clinical variable significantly influenced by the outcome of fracture healing. In trochanteric fractures treated with Ender nails, the quality of fracture reduction was the most valuable predictor of patients' recovery of walking ability.

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The in vivo kinematics of the knee in 7 patients with moderate medial gonarthrosis was analyzed before and 6 months after high tibial osteotomy using roentgen stereophotogrammetric analysis. The inclination of the femorotibial helical axis of rotation did not change with knee flexion or after surgery. The femorotibial rotation increased after surgery. No consistent change in patellar position after surgery was found. Patella translated laterally as the knee was flexed with a maximum patellar translation of about 15 mm and rotated internally with a maximum patellar internal rotation of about 15 degrees. There was no significant change in patellar translation or rotation after surgery. There was a good concordance regarding the size of the tibial wedge removed during surgery, calculated from the Hip-Knee-Ankle radiographs and from the roentgen stereophotogrammetric measurements.

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This study reports the influence of the retroversion angle on the postoperative stability in 50 patients operated on for recurrent shoulder dislocations. Fifty-two shoulders were reviewed by radiographic and clinical examinations. Particular attention was focused on humeral head retroversion, shoulder stability, and range of motion in relation to surgical technique. The retroversion angle was significantly reduced in 30 of 47 shoulders, for which satisfactory radiographs could be achieved. Mean humeral head retroversion was 24 degrees for both dominant and nondominant shoulders. Forty-eight of 52 reexamined shoulders became stable. Four had remaining instability following a Putti-Platt procedure, with a mean retroversion angle of 18 degrees. A reduced humeral head retroversion is therefore proposed as an important factor in creating instability, and may be one explanation for failed stability after soft tissue repair. Irrespective of the type of surgical procedure (Bristow or Putti-Platt), there was a significant decrease in range of shoulder rotation in the operated shoulder compared to the contralateral stable shoulder and to reference values for normal controls. However, decreased rotation was not found to impair shoulder function, and 48 of the 50 reexamined patients generally improved after surgery.

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The aim of this study was to analyse gait improvement one year after high tibial osteotomy and unicompartmental knee arthroplasty in patients with strictly unilateral osteoarthrosis of the medial compartment of the knee. Thirty-six patients, 18 men and 18 women, received a unicompartmental Brigham knee prosthesis and 23 patients, 10 men and 13 women, were operated on with a high tibial osteotomy. Clinical and radiographical assessments were supplemented by a functional test, measurements of thigh muscle torque with a Cybex II dynamometer and analysis on a force plate walkway with electrogoniometers. All patients were assessed prior to, and one year after surgery. Both groups showed overall clinical improvement, as assessed by the British Orthopaedic Association (BOA) score. Pain during walking decreased. The range of knee flexion remained unchanged. The ability to ascend and descend steps improved. The isokinetic thigh muscle torque remained unchanged. In the prosthetic group free walking speed increased from 1.03 to 1.09 m/s (p < 0.001). Step frequency and step length increased (p < 0.001). Single stance phase ratio increased from 0.96 to 0.99 (p < 0.01), indicating a more symmetrical gait. Double stance phase (% gait cycle) of both legs decreased (p < 0.001), indicating a faster transfer of weight during walking. In the osteotomy group, free walking speed did not increase. Step length of the uninvolved leg increased (p < 0.01). Double stance phase of the involved leg decreased (p < 0.001) and double stance phase of the uninvolved leg decreased (p < 0.01). Both groups improved after surgery and there was no difference between the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

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The purpose of this study was to analyse the effects of preoperative physiotherapy on pain and function in 39 patients scheduled for unicompartmental prosthetic knee replacement. Nineteen patients were selected at random to receive preoperative physiotherapy. The control group received no preoperative therapy. Evaluations were performed 3 months prior to surgery, immediately before and 3 months after operation. Evaluations included: Clinical assessment, measurements of the knee muscle strength, self-selected walking speed and the oxygen cost of walking. Three months before surgery the patients in both groups had similar types and levels of problems. Before surgery patients who had received physiotherapy showed slight improvements in pain, perceived stability of the knee during walking, and faster self-selected and maximal walking speeds compared to the control group, but were unchanged in muscle strength, ROM, and oxygen cost. Three months after surgery pain was significantly decreased in all patients, however, no significant differences were found between the two groups for any variable except muscle strength. This was unchanged compared to preoperative values for patients of the control group while patients who received preoperative physiotherapy showed a decrease in strength. In summary, this study did not disclose any major benefit from the program of preoperative physiotherapy tested.

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