Procedure-dependence and tissue factor-independence of hypercoagulability during orthopaedic surgery.

The increased risk for deep vein thrombosis (DVT) after orthopaedic surgery has been well documented as well as hypercoagulable state during both total hip arthroplasty (THA) and total knee replacement (TKR). To investigate the influence of the surgical procedure [posterolateral (PL) or lateral (L) approach for THA, use of tourniquet (TQ) or not use of TQ for TKR] on the hypercoagulability and the role of extrinsic pathway activation and endothelial stimulation during orthopaedic surgery we have examined 40 patients (20 patients undergoing primary THA--10 with PL approach and 10 with L approach--and 20 patients undergoing TKR--10 with TQ application and 10 without TQ). Thrombin-antithrombin complexes (TAT), tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombomodulin (TM) and von Willebrand factor antigen (vWF:Ag) were analyzed before and during the orthopaedic surgery. During THA, TAT plasma levels increased more markedly in patients assigned to the L than PL approach (p <0.05); during TKR an elevation of TAT of higher degree (p <0.05) was observed when TQ was not applicated. Blood clotting activation was significantly (p <0.001) more relevant during THA than TKR. No changes in TF and vWF:Ag plasma levels were observed in all patients undergoing THA and TKR. TFPI plasma levels significantly (p <0.05) decreased 1 h after the end of the THA in group PL and group L, whereas they remained unaffected in the two groups of patients undergoing TKR. Similarly TM plasma levels significantly decreased during THA, but not during TKR. In conclusion, these results show that: 1) the site of surgical procedures and the type of approach affect the degree of hypercoagulability, 2) the blood clotting activation takes place in the early phases of orthopaedic surgery, without signs of extrinsic pathway and endothelial activation.

A five to seven-year follow-up of unicondylar arthroplasty.

Thirty-two unicondylar knee replacements in thirty patients were done between 1972 and 1974. Ten patients were lost to follow-up because of death or other reasons. The remaining twenty-two knees (seventeen medial and five lateral compartments replaced) had a follow-up ranging from five to seven years, with an average of six years. Although the quality and result of these unicondylar arthroplasties were initially considered good, they have subsequently shown a marked deterioration. At the time of this report only one knee was rated as excellent; seven knees, as good; four knees, as fair; and ten knees, as poor. Seven knees (28 per cent) have been converted to a bicondylar prosthesis. The lateral replacements did much better than the medial replacements.

Resurfacing of the patella.

The results of use of twenty-nine patellar resurfacing prostheses in twenty-eight patients were studied. The diagnosis was osteoarthritis in twenty-two knees, chondromalacia in five knees, and habitual dislocation with severe osteoarthritis in two. The follow-up time was from three to six years. A cemented chromium-cobalt prosthesis was used. Of the twenty-nine knees studied, two were rated excellent; fourteen, good; three, fair; and ten, poor. Failure was always due to unrelieved pain.

A comparison of four models of total knee-replacement prostheses.

Twenty-nine knees with unicondylar, sixty-four with duocondylar, fifty with Guepar, and fifty with geometric prostheses were studied. The follow-up ranged from two to three and one-half years. The unicondylar prosthesis was used in the mildest cases and gave the least complications, but the quality of results was not superior to that achieved with the other prostheses. The duocondylar model was best suited for knees with rheumatoid arthritis and mild deformity. The geometric prosthesis was the best condylar prosthesis for osteoarthritis with moderate to severe deformity, but gave the worst results in knees with rheumatoid arthritis. The Guepar prosthesis was used in the worst knees and gave the best results, but it had the highest infection rate and was the most difficult to salvage. A radiolucency was observed in about 60 per cent of the condylar replacements around the tibial component and in 45 per cent of the Geupar replacements around the femoral component. The significance of this cannot yet be determined but it suggest that the fixation may not be ideal. In all types, residual pain was most frequently attributed to the patellar compartment. Patellectomy was not a solution.

Bone-block iliotibial-band transfer for anterior cruciate insufficiency.

The anterior distal part of the iliotibial trace with attached bone block from Gerdy's tubercle was used as an intra-articular graft fixed by a screw to the tibia to control anterior instability (otherwise known as anterior, anteromedial, or anterolateral laxity) in twenty-four knees which were followed for two to four years. Concomitant single-plane 2+ to 4+ medial instability was present in eleven knees and was treated in five of them by simple immobilization, by imbrication of the medial collateral ligament, or by the Vigliani procedure. At follow-up, stability was improved and the result was rated good or excellent in twenty-one (88 per cent) of the twenty-four knees. The operation is applicable to the majority of chronic laxities of the knee and, because no immobilization is necessary, the postoperative care is much simplified and the rehabilitation time is much shorter. The procedure is contraindicated where there is posterior or single-plane lateral laxity.

A ten-year follow-up study of our first one hundred consecutive Charnley total hip replacements.

This study concerns the fate of the first 100 Charnley total hip replacements done in ninety ninety patients at The Hospital for Special Surgery. At the time of this study, the follow-up of the surviving sixty-seven patients ranged from nine and one-half to eleven and one-half year (average, ten years). When studied at an average of ten years after the initial operation, twenty-six of the original 100 hips that had been operated on had been lost to follow-up due to death, and seven could not be traced. Of the remaining sixty-seven hips that were available for clinical evaluation, thirty-seven were rated as excellent; twenty-two, as good; four, as fair; and four, as poor, according to The Hospital for Special Surgery scoring system. The radiographs of fifty-four of the sixty-seven hips were available for this evaluation. Twenty-three of these hips showed radiographic signs of problems that appeared to have no significant bearing on the quality of their clinical results. There was loosening of the femoral component in five hips which occurred within the first three years after operation and then apparently stabilized. One required reoperation eight years after the original surgery. There was one fracture of the femoral stem eight years after the original operation, requiring reoperation. Six hips demonstrated so-called calcar resorption, the greatest measuring fourteen and thirty millimeters. Ten acetabular components showed wear of more than one millimeter, the maximum being five millimeters in both components of a patient with bilateral hip replacement. Two acetabular components migrated, one requiring reoperation due to progressive bone loss nine and one-half years after the original procedure. All three reoperations have been successful to date.

Arthroscopic partial meniscectomy in the anterior cruciate deficient knee.

One hundred ACL insufficient knees were followed for an average of 3.5 years after arthroscopic partial meniscectomy had been performed. Fifty-two percent of the patients obtained a satisfactory result and 41% were able to participate in strenuous sports activities. The arthroscopic partial meniscectomy reduced pain and swelling in a high proportion of cases, but stability was only marginally improved. Negative prognostic factors were: sex (female), generalized laxity, contralateral recurvatum of more than 10 degrees, complete as opposed to partial ACL lesions, Grade III tibiofemoral or patellar chondromalacia, associated peripheral ligamentous laxity, pivot shift of Grade II or greater, and anterior tibial displacement of more than 5 mm as measured with the KT-1000 knee arthrometer.

Long-term study of anterior cruciate ligament reconstruction for chronic instability using the central one-third patellar tendon and a lateral extraarticular tenodesis.

Forty-four patients with symptomatic chronic anterior cruciate ligament instabilities that had been reconstructed with the central one-third patellar tendon and a lateral extraarticular iliotibial band tenodesis were studied at an average followup of 7 years (range, 4 to 10). The cases with associated medial, lateral, or posterior laxity were not included, nor were the cases with more than minimal preoperative degenerative changes. The average age at surgery was 21 years (range, 16 to 33). A postoperative cast was used for 4 weeks. Satisfactory objective stability, which was defined as a KT-1000 side-to-side difference of up to 5 mm at the manual maximum test, was obtained in 37 (84%) of the patients. In 25 patients (57%), stability was restored within normal limits (less than or equal to 3 mm). No deterioration of the KT-1000 stability was noted at two follow-up visits performed by the same examiner (at an average of 4 and 7 years). A return to high-risk sports was possible in 27 (62%) of the patients. Difficulties in regaining a complete range of motion were recorded in 5 (11%) of the patients. A flexion contracture of 5 degrees to 7 degrees was also found in 5 patients. Significant patellofemoral symptoms were present in 4 patients (9%). A 5% to 11% shortening of the patella tendon was observed in 14 (32%) of the knees, but did not correlate with patellar problems. Moderate radiographic changes were noted in eight patients (18%) at followup and correlated with meniscectomy and pain. Overall satisfactory results were obtained in this initial experience in 29 (66%) of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Patellar tendon versus doubled semitendinosus and gracilis tendons for anterior cruciate ligament reconstruction.

The results of intraarticular anterior cruciate ligament reconstruction with either the patellar tendon or the semitendinosus and gracilis tendons (four strands) were prospectively compared in a consecutive series of 60 patients with chronic injuries. A single surgeon performed arthroscopically assisted reconstructions in an alternating sequence. Preoperative and operative data revealed no significant differences between the two groups. After 28 months of followup there were no significant differences in the incidence of symptoms, and recurrent giving way was present in only one knee with semitendinosus and gracilis tendon graft. Return to sport participation was more frequent in the patellar tendon group (80% versus 43%, P < 0.01). A minor extension loss (< or = 3 degrees) was more frequent in the patellar tendon group (47% versus 3%, P < 0.001). Other differences between the two groups were not significant. KT-2000 arthrometer side-to-side difference of anterior displacement > 5 mm at 30 pounds was present in 13% of the knees with patellar tendon grafts and in 20% of those with semitendinosus and gracilis; a patellofemoral crepitation developed in 17% and 3% of the two groups, respectively. Based on these data we routinely use patellar tendon grafts. Semitendinosus and gracilis tendons are preferred in selected cases: older patients, patients with preexisting patellofemoral problems, and those with failed patellar tendon grafts.

Arthroscopically assisted semitendinosus and gracilis tendon graft in reconstruction for acute anterior cruciate ligament injuries in athletes.

We evaluated 69 arthroscopically assisted anterior cruciate ligament reconstructions for acute tears at an average followup of 60 months. We used a distally based single semitendinosus and gracilis tendon graft passed over the top and fixed to the femur. Combined medial collateral ligament lesions were seen in 30 knees, and they were repaired when found in the distal third (18 knees). The patients were instructed to recover motion preoperatively, and an early range of motion program was used postoperatively. At followup, symptoms of giving way were seen in five knees (7%). Graft failure was seen in seven knees (10%); failure was defined as a positive pivot shift (clunk or gross) or a side-to-side difference in anterior tibial displacement greater than 5 mm, as measured with a KT-1000 arthrometer. Permanent extension loss (3 degrees to 5 degrees) was found in two knees (3%). Patellofemoral crepitation was seen in eight knees (12%), but the condition was symptomatic in only one knee. Forty-six patients (67%) were active in pivoting sports before surgery and 37 (54%) remained active in these sports at followup. We concluded that this operation is simple, effective, and has a low complication rate. Further studies are necessary to elucidate if a stronger graft (e.g., a patellar tendon) would decrease the rate of graft failure without increasing complications.

Posteriorly stabilised total-condylar knee replacement. Three to eight years' follow-up of 85 knees.

We have reviewed 85 knees in 71 patients after total-condylar posteriorly stabilised (Insall-Burstein) knee replacement with an average follow-up of five years. Excellent or good results were obtained in 90% with an average maximum flexion of 98 degrees. The four poor results (5%) included two with deep infection, one with patellar dislocation and one with loosening. Four other knees (5%) showed signs of probable tibial loosening, but the patients were asymptomatic, the clinical results had not deteriorated with time and lucent lines had not progressed. Varus alignment of the knee and a varus tilt of more than 2 degrees of the tibial component correlated with the incidence of lucent lines around the tibial implant. No patellar stress fractures were seen but impingement symptoms were present in 20%, although they were troublesome in less than half of them. The virtue of the prosthesis lies in its versatility for use in the severely deformed joint.

Idiopathic osteonecrosis of the knee. Aetiology, prognosis and treatment.

This is a prospective study of 105 knees in 91 patients with idiopathic osteonecrosis of the femoral condyles, with an average follow-up of five years in 101 knees. Forty-eight of the 75 patients in whom the body weight was studied were obese and four of the 33 patients in whom a densitometry study was done showed decreased bone density. Prognosis is unfavourable if the lesion is larger than five square centimetres and if its width is more than 40 per cent of that of the condyle. Of the 22 patients followed up after conservative treatment 80 per cent were satisfactory. Of the 11 knees treated by arthrotomy alone 55 per cent were satisfactory. Of the 31 knees treated by osteotomy (21 with associated arthrotomy) 87 per cent were satisfactory. Arthrotomy did not significantly improve the results of osteotomies. The ideal correction was to 10 degrees of valgus. Of the 37 knees treated with replacement 95 per cent were satisfactory, and the best results were obtained with the total-condylar prosthesis.

[Risk factors and prevention of infections of hip and knee prostheses]. / Entità del rischio e prevenzioni delle infezioni nelle protesi d'anca e ginocchio.

Prevention of deep periprosthetic infection requires appreciation of the contributing factors to this phenomenon. The concept of an interdependent relationship between the bacteria, wound and host is most useful when considering the prevention of infections. Establishment of infection depends on the number and virulence of the bacteria, the host's ability to eliminate those bacteria and the status of the wound. Multiple variables contribute to the deposition and proliferation of bacteria into the wound environment which enhance the infectious process, such as the presence of a prosthetic implant or medical conditions and medications which impair the patient's defense. Prevention must address optimization of the wound environment, minimizing the number of bacteria into the wound and augmenting the host defenses. Administration of prophylactic antimicrobials prior to skin incision reduces the incidence of wound infections. The optimal antimicrobial agent should have excellent in vitro activity against staphylococci and streptococci, a long serum half-life, good tissue penetration, be non-toxic and inexpensive.

Results of arthroscopic excision of the fragment in the treatment of osteochondritis dissecans of the knee.

PURPOSE: To evaluate clinical and radiological results of arthroscopic excision of the fragment and debridement of the crater in the treatment of osteochondritis dissecans of the knee (OCD). TYPE OF STUDY: Case series. METHODS: We investigated 20 patients with partial or complete detachment of the OCD fragment. The average age at surgery was 21 years (range, 12 to 32 years). All the patients were treated by the same surgeon. They were evaluated at an average follow-up of 9 years (range, 6 to 17 years). RESULTS: The combined subjective and objective evaluation showed excellent and good results for 85% of the patients. Radiographic studies showed 2 grades of worsening (from no degenerative signs preoperatively to narrowing of the joint line up to 50% at follow-up) in 1 patient (5%). One grade of worsening (Fairbank's changes without joint space narrowing) was found in 45% of weight-bearing anteroposterior radiographic views and in 35% of weight-bearing bent knee posteroanterior views. Statistical correlations were significant between radiographic degenerative changes and the size of the osteochondral lesion at surgery, with larger lesions resulting in greater degenerative changes. CONCLUSIONS: The arthroscopic removal of an osteochondral fragment and debridement of the crater is a viable option in the treatment of grade III and IV OCD lesions. Results are better in lesions less than 2 cm(2).

Mobile and fixed bearing total knee prosthesis functional comparison during stair climbing.

OBJECTIVE: The purpose of this investigation is to determine the functional performance of the mobile bearing total knee replacement prosthesis as compared to the fixed bearing type total knee replacement prosthesis. DESIGN: Kinematics, kinetics, and electromyography data were gained from 10 patients with mobile bearing and 10 patients with a fixed bearing posterior stabilized Insall Burstein II total knee replacement during ascending and descending stairs. A control group of 10 normal subjects, matched by sex and age, was also analysed. BACKGROUND: No significant biomechanical differences in patients with different total knee replacement designs have been reported from level-walking studies. Slightly better performance of posterior retaining with respect to cruciate sacrificing total knee replacement designs have been claimed from stair climbing studies. Only one study has been conducted regarding mobile versus fixed bearing total knee replacement assessed by gait analysis. This study did not show any biomechanical differences between the two groups. METHODS: Motion analysis was used to quantify the knee kinematics, kinetics, and electromyography (right and left longissimus dorsi, gluteus medius, rectus femoris, biceps femoris, semitendinosus, gastrocnemius and tibialis anterior muscles) during stair ascent and descent. RESULTS: The mobile bearing group demonstrated a reduced knee extensor moment during stair climbing and descending, and a reduced knee adductor moment during stair climbing. When ascending stairs, most of the mobile bearing patients show a peak knee flexion and a peak knee flexion moment at the late stance phase during the double support period. This kinematic and kinetic pattern is absent in normal subject. Both mobile bearing and fixed bearing groups showed abnormal electromyography patterns in both descending and ascending. CONCLUSIONS: During stair climbing, the mobile bearing design demonstrates a different kinematic pattern to the fixed bearing total knee replacement. Lower limb compensatory mechanisms seemed to be adopted particularly by the mobile bearing patients during ascending stairs. RELEVANCE: Total knee replacement patient with mobile bearing design can feel excessive femoro-tibial motion during daily living activities such as stair climbing and descending. Proprioceptive control of this tibio-femoral translation is needed as demonstrated by the lower limb compensatory mechanism. This data suggest that antero-posterior constraint structures (ligamentous or mechanical) are important to obtain reproducible knee kinematics.

Flexion-extension gap changes during total knee arthroplasty: effect of posterior cruciate ligament and posterior osteophytes removal.

Flexion and extension gap heights were measured in 50 consecutive primary posterior-stabilized total knee arthroplasties (TKAs) to determine whether posterior cruciate ligament (PCL) release or re-establishment of the posterior condylar recess increased gap width. After PCL release, a slight symmetrical increase was noted in both gaps. In extension, gap width increased on average 1.3 mm and 1 mm in the medial and lateral compartments, respectively. The same pattern was observed in flexion, averaging 1.3 mm medially and 1.3 mm laterally. Another increase in the two gaps was observed after the posterior condylar osteophytes were removed and the posterior recess was re-established. The gaps in extension increased, with respect to the base-line value, on average 1.8 mm medially and 1.8 mm laterally, whereas flexion increased an average 2 mm medially and 2.2 mm laterally. No statistical differences were noted between flexion and extension gaps. No independent differences between the flexion and extension gaps were found in any surgical phase. Posterior cruciate ligament removal and re-establishment of posterior condylar recess does not require additional consideration in gap balancing during posterior-stabilized TKA.

[Scanning electron microscopy study of the meniscus of the knee in patients with anterior cruciate ligament lesions]. / Studio al microscopio elettronico a scansione del menisco del ginocchio in soggetti affetti da lesione del ligamento crociato anteriore.

In the aim of bringing a contribution to role of the knee menisci and the functional connection between meniscal lesions and knee joint instability, four patients have been studied, who underwent arthroscopy for sub-acute tear of anterior cruciate ligament without clinical or morphological evidence of meniscal pathology. In these patients biopsies have been taken from one of the menisci and processed for the examination by the SEM. As control, meniscal fragments from two healthy knees have been studied from patients who underwent amputation at thigh for accidental trauma with irreparable lesion of femoral artery. In patients affected by ligamentous tear, on the meniscal surface a lot of deposited material appears, as well as many microlesions as clefts or cracking and distortion of superficial collagenous fibers. All described alteration are more evident in the central portion of menisci than in the anterior or posterior horns. The above mentioned patterns suggest a strong correlation of the knee instability due to ligamentous lesions and meniscal degenerative process which would onset before its clinical or macroscopical evidence.

[Arthroplasty of the knee using total condylar prosthesis. Long term results (10 to 17 years) and survival analysis]. / Arthroplastie du genou par prothèse Total Condylar. Résultats à long terme (10 à 17 ans) et analyse de survie.

INTRODUCTION: This study refers to the first 76 Total Condylar knee prostheses that were implanted in 66 patients, with a minimum follow-up of 10 years. MATERIALS AND METHODS: There were 54 women and 12 men with an average age of 65 years (range 45-81). The diagnosis was osteoarthrosis in 63 knees and rheumatoid arthritis in 13. We were able to review 54 prostheses with an average follow-up of 13 years (10-17) using the rating system of the Hospital for Special Surgery and the Survivorship analysis. RESULTS: The results were excellent and good in 72.5 per cent knees and fair and poor in 22 per cent, 3 knees (5.5 per cent) had been revised for deep infection in 2 cases and for aseptic loosening in 1. Pain at rest was absent or mild in all but one patient; walking pain was absent in 32 knees (63 per cent), mild in 12 (23 per cent), moderate in 5 (10 per cent) and severe in 2 (4 per cent). Average range of motion was 89 degrees, ranging from 40 degrees to 120 degrees. A flexion contracture greater 5 degrees was seen in 8 knees (16 per cent). Instability in the frontal plane tested in full extension was more than 5 degrees in 10 patients (19.5 per cent). A significant deterioration of the results occurred in the last 4-5 years, since in 1988 excellent and good results were still 82 per cent. A loss of postoperative alignment of 5 degrees or more was observed in 11 knees: aseptic loosening was identified in 2 of these cases and deformation of the tibial component was seen in 1 knee. In the remaining 8 knees we observed increased lateral instability, compared to the postoperative evaluation. In this group of 8 knees we measured in the AP view the thickness of the tibial component on the lateral and medial side. We found polyethylene wear on the medial side in 4 cases. Ten of the 11 knees with loss of alignment had an early postoperative femoro-tibial axis less than 5 degrees. We observed radiolucent lines in 18 patellar and 27 tibial components. A width greater than 2 mm, correlated to an extension to 5 or more zones, was seen in 3 tibial components with aseptic loosening. Survivorship analysis using aseptic loosening, mechanical failure of the polyethylene and deep infections as end point gave a cumulative success rate at 10 years of 92 per cent% with 95 per cent confidence interval ranging from 85.1 to 98. DISCUSSION: Our study reports a lower percentage of excellent and good results if compared to other series of Total Condylar prosthesis with a comparable follow-up. A significant deterioration of the results occurred in the last years, but this was often not related to the knee itself but to poor general conditions in some patients. In this series there is a relevant number of knees with a post-operative alignment that today we don't consider correct and all the aseptic loosenings occurred in knees with a tibial component positioned in varus. CONCLUSION: Survivorship analysis gave a cumulative success rate comparable with those reported in other studies and confirmed the durability and longevity of this model of prosthesis.