A comparison of isokinetic strength testing and gait analysis in patients with posterior cruciate-retaining and substituting knee arthroplasties

Fourteen patients with a posterior-stabilized prosthesis in one knee and a posterior cruciate-retaining prosthesis in the contralateral knee and both scoring good or excellent on the Hospital for Special Surgery (HSS) knee scale were evaluated by isokinetic muscle testing and comprehensive gait analysis at a mean follow-up of 98 months after arthroplasty. The average HSS knee score (93 points) and the average Knee Society score (94 points) were the same for the cruciate-retaining and posterior-stabilized knees. No differences were noted between the cruciate-retaining and the posterior stabilized knees with respect to isokinetic muscle testing parameters (peak torque, endurance, angle of peak torque, and torque acceleration energy) for both quadriceps and hamstrings. No significant differences were found between the cruciate-retaining and the posterior-stabilized knees with regard to gait parameters, knee range of motion, and electromyographic waveforms during level walking and stair climbing. Cruciate-retaining and posterior-stabilized total knee prostheses perform equally well during level gait and stair climbing.     

Complications from the hinged GUEPAR prosthesis after resection of knee tumor. 102 cases

PURPOSE: The purpose of this study was to present the complications which occurred in knee replacement with the GUEPAR prosthesis, after bone tumor resection. We tried to point out complications in relation to prosthetic design and surgical technique. MATERIAL AND METHOD: Between 1972 and 1993, 90 patients had a knee resection, for 80 malignant and 10 benign tumors. There were 51 males and 49 females, aged 12 to 75 years (mean age 35). Fifty-six distal femur resections and 34 proximal tibial resections were performed. Length of resection averaged 16 cm (9 to 30). The reconstruction was always achieved with a cemented, custom-made GUEPAR prosthesis. Including revisions, there was a total of 102 prostheses in 90 patients. A patellar resurfacing was performed in 64 cases. An allograft reconstruction was associated in 39 knees. In all tibial resections and in two extra-articular femoral resections, the extensor mechanism had to be reconstructed. Several reconstruction techniques were associated, in which 19 medial gastrocnemius transfers. The prosthesis design was slightly modified with time. Ten patients received radiotherapy, and 55 had chemotherapy. RESULTS: Results and complications were retrospectively assessed, with an average follow-up of 4.3 years (1 to 22). Six patients were lost for follow-up, 62 patients were alive, with no evolutive disease, 13 had an evolutive disease and 10 were deceased from disease. Nineteen patients had distant metastasis and 17 had local recurrences. Apart from intraoperative complications, late mechanical complications included: 13 aseptic loosening, 2 femoral shaft fractures, 18 knee contractures, 5 femoral stem fractures and, 18 intra-articular instabilities related to wear of the hinge-axis. In the 39 allograft-composite prostheses, only 15 had a favorable evolution. There were 15 extensor mechanism failures and 13 knees had persistent infection. There was a total of 94 reoperations in the 90 patients. In 28 cases, the initially implanted prosthesis was removed. There were also 18 revisions, 7 amputations and 3 arthrodeses. Survivorship analysis showed a 60 per cent probability for the initial prosthesis not to be revised at 10 year-follow-up, apart from oncologic complications. DISCUSSION: Results with allograft-composite reconstruction were not better than with massive prosthesis. When needed, soft tissue coverage and patellar tendon augmentation would better be performed with gastrocnemius plasty. Polyethylene and steel bushes were not solution for hinge axis wear.     

Treatment of major defects of bone with bulk allografts and stemmed components during total knee arthroplasty

We reviewed the results an average of fifty months (range, twenty-four to 120 months) after the use of thirty-five allografts in thirty patients during primary or revision total knee replacement. Twenty-nine femoral-head allografts, five distal femoral allografts, and one proximal tibial allograft were used in conjunction with a long-stemmed implant to reconstruct large osseous defects. The patients were evaluated clinically, radiographically, and subjectively (with use of a questionnaire). Twenty-six (87 per cent) of the thirty patients had a good or excellent clinical result, and no revisions were necessary. As none of the patients had collapse of the graft, subsidence of the implant, or revision, we believe that the outcome of treatment with a femoral-head allograft, particularly in association with a component inserted with cement, is excellent. Four non-porous-coated components were placed without cement on structural allografts. Radiographically, three of those components subsided, but none of the three needed revision and two were associated with a good clinical result. Our current practice is to cement components in all arthroplasties involving grafting. Our findings suggest that the use of a stemmed component reduces the stress on the allograft, host bone, and fixation interface. In addition, such a component contributes to the longevity of a total knee replacement associated with a bone graft. Additional studies with long-term follow-up are necessary to confirm this outcome.     

Duo-condylar knee arthroplasty: hospital for special surgery design

This is a report of 94 knees in 88 patients with the duo-condylar type of knee arthroplasty. The follow-up period of time was between 2 to 4 years with an average of 3 years. The rheumatoid to osteoarthritic patient ratio was 3 to 1. The overall results were excellent in 37.5 per cent, good in 37.5 per cent, fair in 16 per cent, and poor in 9 per cent. The main causes of failure and poor results were: (1) under or over correction of deformity leading to subluxation and/or instability of the knee; (2) loosening of the tibial component, and (3) symptoms arising from the patellofemoral joint. The revision rate is 5.5 per cent. The progressive radiolucency at the cement bone bond is 26 per cent of which 16 per cent is up to 1 mm and 10 per cent is between 1.5 to 3 mm. To further improve the results of arthroplasty, one should take into consideration (1) replacement of the patellofemoral joint, (2) insertion of the prosthesis in the proper anatomical location under correct tension of the ligaments and capsule with the help of proper instrumentation and (3) improvement in fixation of the tibial component.     

Characteristics of impaired awareness after traumatic brain injury

The condylar constrained total knee arthroplasty was performed on 29 patients undergoing 33 procedures and were reviewed clinically and radiographically at an average follow-up of 5 years (range, 2-10 years). There were 21 women and 8 men. The average age at the time of surgery was 70 years (range, 32-84). Of the 16 knees that were revision total knee arthroplasties, 8 had a previous infected total knee arthroplasty, and 17 knees had severe deformities requiring the use of the condylar constrained prosthesis. The patients were rated according to the Knee Society clinical and radiological evaluation protocol. Measurements of femoral and tibial component position were obtained as well as femoral tibial angle, patella position, and cement bone radiolucencies. All clinical measurements were made by an independent physical therapist. Clinical results revealed an improvement from an average preoperative knee score of 38 points to an average postoperative score of 86 points. The clinical results for 19 (58%) knees were excellent, 8 (24%) had a good result, 1 (3%) was fair, 2 (6%) were poor, and 3 (9%) were failures. The patients' average functional levels increased from 24 to 58. The final average flexion was 96 degrees. Three knees have been revised (9%). One was revised for recurrent infection, one for periprosthetic fracture, and one for mechanical loosening of the tibial component. There were no other knees with evidence of radiologic loosening. We conclude that the condylar constrained total knee prosthesis provides an acceptable solution for revision and complex primary total knee replacements at an intermediate follow-up term of 5 years.     

Low friction total knee arthroplasty with the alumina ceramic condylar prosthesis

This paper evaluates the failure and wear properties of the alumina ceramic posterior cruciate condylar total knee prosthesis, and reports the preliminary clinical results of this prosthesis. Thirteen sets of the alumina ceramic prostheses were used for destruction and wear tests. The average ultimate load in the static destruction tests showed 2.63 x 10(4) Newtons in the femoral component, and 1.28 x 10(4) Newtons in the tibial component. The average ultimate energy in the impact destruction tests showed 22.1 Joules in the femoral components, and 20.3 Joules in the tibial components. The wear test demonstrated that the average depth of wear was 0.04 mm in the alumina ceramic prostheses, and 0.20 mm in the Vitallium prostheses. Observation of the UHMWPE wear surface with a scanning electron microscope indicated many deep scratches and a scooped concave lesion in the Vitallium prostheses; there were few deep scratches in the alumina ceramic prostheses. Thirty patients underwent 32 total knee arthroplasties using the alumina ceramic posterior cruciate condylar prosthesis between 1988 and 1990. The results were evaluated as excellent for 59%, good for 28%, fair for 10%, and poor for 3%. Critical roentgenographic review demonstrated no cases of loosening or sinking after arthroplasties using the alumina ceramic prosthesis. Radiolucent lines were observed only in 4 knees (12%) cases. All were observed around the tibial components, but were less than 1 mm in thickness. The frequency of the radiolucent lines is less than that observed in the Vitallium prosthesis at the same followup period. The alumina ceramic posterior cruciate condylar prosthesis may have sufficient durability and excellent wear properties for low friction total knee arthroplasty.     

Primary total hip reconstruction with a titanium fiber-coated prosthesis inserted without cement

A prospective study was done of the intermediate-term clinical and radiographic results of 121 total hip arthroplasties in which a Harris-Galante porous titanium-fiber-coated prosthesis was inserted without cement in 110 patients. The average age at the time of the operation was forty-nine years (range, twenty to seventy years). The average duration of follow-up was sixty-seven months (range, fifty-five to seventy-nine months). The average preoperative Harris hip score was 55 points, and the average postoperative score was 93 points. One acetabular component was revised due to recurrent dislocation. Eleven femoral implants were unstable, and of these, four were revised. Cortical erosion was present around the distal part of the femoral stem in nine patients (8 per cent) who had stable implants, and one of these femoral implants was revised because the erosion was extensive. Survivorship analysis at five years revealed a 97 per cent chance of survival (95 per cent confidence limit, 0.937 to 1.0) of the Harris-Galante femoral-stem implant inserted without cement.     

Statistics of total knee replacement: partial and total knee replacement, design St. Georg: a review of a 4-year observation

Since 1969, we have used 2 different types of knee prostheses to reconstruct arthritic knees. The surface replacement prosthesis (sledge) is indicated where ligamentous stability is present and angular deformity is not severe. In addition, the sledge prosthesis may be implanted with good results in selected acute comminuted tibial plateau fractures. The total hinged prosthesis of metal design is recommended in knees which are severely deformed, and unstable, and therefore not suitable for the sledge prosthesis. Marked relief of pain was the most significant result in our patients. Residual knee pain was most frequently due to patello-femoral pain and, when severe, this was satisfactorily controlled by performing a patellectomy. Motion was usually maintained at the preoperative range or improved, mainly by reducing or eliminating the knee flexion contracture. In a high percentage, the unicompartmental sledge prosthesis has given excellent results. However, we tend to insert a bi-compartmental sledge prosthesis because experience has shown that even slight damage of the articular surfaces of the opposite side is likely to further deteriorate rapidly. Although a significant number of complications occurred, these have been minimized by further conservative and operative treatment. We anticipate a further reduction in complications based on our initial experience, and prosthetic revisions.     

Hinged total knee arthroplasty

Analysis of an on-going prospective study of seventy-seven hinged total knee arthroplasties in sixty-seven patients revealed that most patients had improvement in function, although major complications occurred in eighteen knees (23.4 per cent. These complications included sepsis, loosening, patellar tendon rupture, peroneal palsy, and patellar subluxation. Eight of nine knees with deep sepsis required removal of the prosthesis, and three of sixteen knees with patellar pain required realignment of the quadriceps. When prosthetic failure occurred, salvage of a functional extremity was difficult. Hinged total arthroplasty is not without its problems, and a cautious approach to its use is indicated. Whenever possible, a moderately constrained replacement arthroplasty should be considered.     

Demographic biases of scoring instruments for the results of total knee arthroplasty

Four knee-scoring systems were used to evaluate 200 adult subjects who had no history of injury, abnormality, or treatment of the knees, hips, lower extremities, or spine. All subjects were in the age-range (fifty to 100 years; average, 65.5 years) typical of candidates for total knee replacement. In addition to a physical examination, complete demographic data were collected for each subject. The knee scores were normalized by dividing the observed score by the maximum possible score. The average normalized total knee score was 91 per cent (range, 22 to 100 per cent) according to the knee score of The Hospital for Special Surgery, 95 per cent (range, 10 to 100 per cent) according to the system of Hungerford and Kenna, 89 per cent (range, -7.75 to 100 per cent) according to a modification of the scoring system of The Knee Society, and 95 per cent (range, 26.5 to 100 per cent) according to the system of Hofmann et al. Demographic variables that had a significant negative correlation with the knee scores included advanced age (particularly of eighty-five years or more), a family income below the poverty level, and two major medical conditions or more. Observed differences in knee scores between different study groups that have not been matched for various clinically relevant factors are at least as likely to represent differences in the patient populations as they are to represent differences in the operative technique or the design of the implant.     

2-stage reimplantation for infected total knee replacement

Between 1977 and 1983, 64 infected total knee replacements in 60 patients were treated with a 2-stage protocol for reimplantation. The clinical results and survivorship were determined at an average followup of 7.5 years (range, 2-17 years). Surgical protocol included removal of the prosthesis and all cement with thorough debridement of bone and soft tissues. This was followed by 6 weeks of parenteral antibiotics and then reimplantation of a new prosthesis. At followup, 6 knees (9%) had become reinfected, but only 2 with the same organism. Four knees had been revised: 3 for aseptic loosening and 1 for a periprosthetic femur fracture. Two other knees were impending failures due to aseptic loosening. The average Hospital for Special Surgery knee score was 78 points with 18 excellent, 28 good, 13 fair, and 5 poor results. Seventy-eight percent of patients were satisfied with the overall result of their reimplanted prosthesis and 95% think that they made the right decision in undergoing total knee arthroplasty. The 10-year predicted survivorship of 2-stage reimplantation is 77.4%. Two-stage reimplantation with a 6-week course of parenteral antibiotics is an effective means to eradicate deep infection and to provide a functional knee. The long term functional results and overall survivorship are comparable with the results of revision of aseptic failed total knee arthroplasty.     

The effects of an artificial meniscus substitute in a knee joint with a resected anterior cruciate ligament. An experimental study in rabbits

A Dacron meniscus prosthesis was substituted for the medial meniscus in an anterior cruciate ligament (ACL) resected rabbit knee. At three months, the joints were evaluated biomechanically, with gross and histologic inspection. In a paired comparison with the contralateral knee, differences between ACL resection with intact, incised, or resected medial menisci were evaluated. Knees with intact menisci and ligaments served as controls. Because of cartilage destruction, soft-tissue hypertrophy, and increased anterior laxity, joint stiffness was less than normal in all ACL-resected knees. Ingrowth and stable fixation, especially of the posterior horns of the prostheses and the incised menisci, were rare. Almost all normal menisci had ruptured in the same area. Anterior cruciate ligament resection led to severe osteoarthrosis in both compartments, regardless of initial meniscal treatment. Knees with prostheses had the same incidence and severity of osteoarthrosis as knees with meniscus resection. Anterior cruciate ligament resection alone induced excessive osteoarthrosis and synovitis and diminished the effects of different meniscal treatments three months earlier.     

Knowledge of diet and blood pressure among African Americans: use of focus groups for questionnaire development

The long-term results were reviewed for seventy-two patients (seventy-five knees) who had had a bone-patellar ligament-bone intra-articular reconstruction of the anterior cruciate ligament between August 1984 and May 1992. The mean age of the patients at the time of the operation was forty-five years (range, forty to sixty years). Three patients had a bilateral procedure. The primary mechanisms of injury were accidents that occurred during skiing (thirty-two knees), tennis (fourteen knees), and soccer (five knees). We analyzed the responses to subjective questionnaires, the functional results, and the objective clinical data. The clinical examination included assessment of the range of motion, performance of Lachman and pivot-shift tests, and measurements with use of a KT-1000 arthrometer. All knees were evaluated with use of three common rating scales: that of Lysholm and Gillquist; that of The Hospital for Special Surgery, as modified by Insall et al.; and the International Knee Ligament Standard Evaluation Form. At the latest follow-up evaluation, at a mean of fifty-five months (range, twenty-six to 117 months), three patients reported pain or swelling. No patient reported giving-way or symptoms related to the patellofemoral joint. The mean range of extension was -12 to 6 degrees, compared with -8 to 42 degrees preoperatively, and the mean range of flexion was 112 to 150 degrees, compared with 52 to 154 degrees preoperatively. Flexion was limited to 112 degrees in one patient, but this was 5 degrees greater than that of the uninvolved knee. Sixty knees (80 per cent) had a negative pivot-shift test, and ten knees (13 per cent) had a grade of 1+. On testing with the KT-1000 device at maximum manual pressure, the mean difference between the injured and uninjured knees was found to have improved by 5.1 millimeters, from 6.4 millimeters preoperatively to 1.4 millimeters postoperatively (p < 0.01). The grade on the International Knee Ligament Standard Evaluation Form improved markedly; seventy-two knees (96 per cent) had a grade of C or D preoperatively, whereas seventy knees (93 per cent) had a grade of A or B postoperatively. The Hospital for Special Surgery score improved from a mean of 69 points preoperatively to a mean of 92 points postoperatively (p < 0.01). The mean score according to the scale of Lysholm and Gillquist increased from a mean of 63 points preoperatively to a mean of 94 points postoperatively (p < 0.01). All patients indicated that they were pleased with the result of the procedure. Bicycling was resumed at a mean of four months; jogging, at a mean of nine months; skiing, at a mean of ten months; and tennis, at a mean of twelve months.     

Penile prostheses for the management of the neuropathic bladder and sexual dysfunction in spinal cord injury patients: long term follow up

During the last 10 years, 90 penile prostheses were implanted in 82 patients with spinal cord injury. Surgery was done 1 month to 25 years (average 4.8 years) after the injury. The follow up period ranged from 1 to 10 years (average 4 years). A prosthesis was implanted for urinary management in 51 patients (62%), for sexual dysfunction in 10 patients (12%) and for both purposes in 21 patients (26%). Ninety-three per cent of the patients who used the implant for urinary management and 64% of the patients who used it for sexual dysfunction were satisfactory. We experienced three extrusions and nine surgical removals due to pain, difficulty of catheterisation and infection (the complication rate was 13.3%). Generally speaking, a penile prosthesis improves the quality of life of patients with spinal cord injury significantly; however, extrusion and infection are still significant problems.     

Core decompression for avascular necrosis of the distal femur: long term followup

Seventy-nine knees (45 patients) with a diagnosis of avascular necrosis of the distal femur treated between 1978 and 1989 were evaluated. All patients had a corticosteroid association (had been treated with >30 mg of prednisone for >2 weeks predating by at least 6 months the onset of avascular necrosis). Thirty-two knees were managed with protected weightbearing and rest. Core decompression was performed at a minimum of 3 months after the onset of symptoms in another 47 knees. The knees treated with protected weightbearing had an average asymptomatic period of only 11 months and all but 6 (18%) proceeded to total knee replacement within 6 years. Core decompression yielded good or excellent results in 73% of the knees at an average followup of 11 years (range, 4-16 years). Of the 13 knees with failed core decompression, 7 were asymptomatic for greater than 5 years. A subset of 26 knees from each group was matched for age, gender, diagnosis, Ficat and Arlet Stage, and length of followup. The matched noncore group had 23% survival as compared with 74% survival in the core group. This long term followup suggests that core decompression may slow the rate of symptomatic progression of avascular necrosis of the knee. In addition, core decompression may extend the symptom free interval in certain patients and may delay the need for more extensive procedures such as total knee arthroplasty.     

Responses of human single motor units to transcranial magnetic stimulation

The authors analyse the results of 51 unicompartmental knee prostheses with 1 to 12 years follow-up (mean follow-up: 5 years). The results were evaluated using the scoring system of the "Knee Group" of the SO.B.C.O.T. (Société Belge de Chirurgie Orthopédique et de Traumatologie). This analysis demonstrates that the quality of the results depends on implant positioning. The authors suggest positioning the tibial implant parallel with the healthy plateau and slightly distal, i.e. to position the tibial implant perpendicular to the epiphyseal axis and not to the mechanical axis, as is systematically done with the usual tibial cutting guides. When this ideal positioning was respected, 77.5% of the patients had a score above 90 points (out of a possible maximum of 100 points) and 12.5% had a score between 75 and 89 points. When this condition was not respected, none of the knees obtained more than 75 points. The difference was statistically significant (p = 0.0001).     

Flexion instability after primary posterior cruciate retaining total knee arthroplasty

Between 1990 and 1995, 25 painful primary posterior cruciate ligament retaining total knee arthroplasties were revised for flexion instability. These patients shared typical clinical presentations that included a sense of instability without frank giving way, recurrent knee joint effusion, soft tissue tenderness involving the pes anserine tendons and the retinacular tissue, posterior instability of 2+ or 3+ with a posterior drawer or a posterior sag sign at 90 degrees flexion, and above average motion of their total knee arthroplasty. The primary total knee arthroplasty was performed for osteoarthritis in 23 patients and rheumatoid arthritis in two patients. There were 13 male and 12 female patients and their mean age was 65 years (range, 35-77 years). Before the revision operation, Knee Society knee scores averaged 45 points (range, 17-68 points) and function scores averaged 42 points (range, 0-60 points). Twenty-two of the knee replacements were revised to posterior stabilized implants and three underwent tibial polyethylene liner exchange only. Nineteen of the 22 knee replacements revised to a posterior stabilized implant were improved markedly after the revision surgery. Only one of three knee replacements that underwent tibial polyethylene exchange was improved. After the revision for flexion instability, Knee Society knee scores averaged 90 points (range, 82-99 points) and function scores averaged 75 points (range, 45-100 points) for the 20 knees with a successful outcome. This study suggests that flexion instability can be a cause of persistent pain and functional impairment after posterior cruciate ligament retaining total knee arthroplasty. A revision operation that focuses on balancing the flexion and extension spaces, in conjunction with a posterior stabilized knee implant, seems to be a reliable treatment for symptomatic flexion instability after posterior cruciate retaining total knee arthroplasty.     

Head and neck replacement endoprosthesis for pathologic proximal femoral lesions

Records of 28 patients with pathologic lesions in the proximal femur treated by implantation of a femoral head and neck replacement prosthesis between 1984 and 1995 were reviewed. Mean clinical followup was 47.8 months in the eight living patients and 15.8 months in the 20 patients who had died. The underlying diagnosis was metastatic disease or myeloma in 22 patients. The most frequently occurring indication for implantation of this device was a pathologic fracture in 26 patients (18 displaced, eight impending), followed by resection and reconstruction in two patients. All femoral components were cemented: 23 were bipolar hemiarthroplasties and five were total hip arthroplasties. Implant survivorship was good (93%), with only two prostheses removed during the followup period, both for infection. However, radiographic analysis revealed increasing lucencies with time, particularly in the most proximal zones, resulting in radiographic failure in an additional case. Deep infection occurred in three cases, leading to resection arthroplasty in two patients. Periprosthetic fractures occurred in three cases, but only one occurred intraoperatively. Despite a high complication rate, the good implant survival during the shortened life span of these patients supports the continued use of femoral head and neck replacement prostheses in this population.     

Complications following total knee replacement

Forty-two months follow-up examinations on 30 total knee arthroplasties revealed the following significant complications: phlebothrombosis, 13 knees (46%); pulmonary embolism 3 patients (11%); asymptomatic loosening, 8 knees (11.4%); symptomatic loosening, 3 knees (4.8%); superficial infections, 4 knees (5.4%); deep infections, 4 knees (5.4%); peroneal palsy, 3 patients (4.3%). Early detection of thrombophlebitis by 125I fibrinogen scan and possible aspirin prophylaxis were evaluated. In view of the limited number of encouraging results, e.g. excellent 58.6 per cent; good 28.5 per cent; fair 5.4 per cent and poor 7.1 per cent, caution is advocated until extensive time elapses for more clinical experience with total knee arthroplasty.     

Reoperation for failed prosthetic replacement used for limb salvage

Patients with segmental bone and joint replacement prostheses because of tumors increasingly need revision surgery because of their long term survival. Between 1970 and 1990, 208 custom prosthetic replacements were performed for limb salvage in patients with tumors. Reoperations were required in 52 patients. The mean time to reoperation was 37 months. The reoperation procedures included 35 prosthetic revisions, 11 amputations, four arthrodeses, one vascularized fibular graft, and one open reduction and internal fixation of a fracture with supplemental bone graft. Functional assessment using the new Musculoskeletal Tumor Society scoring system was available for the 36 living patients, and their mean rating was 63% (18.9) at 12 years' mean followup. Of the 35 patients who received a new prosthesis, 12 (33%) patients needed a third operation at mean followup of 68 months. The probability of prosthetic survival in the group of 35 patients needing revision to the same or another prosthesis was 79% at 5 years and 65% at 10 years. The chance and frequency of needing reoperation increased as patients survived longer. Reoperations for tumor recurrence or infection usually resulted in amputation. Reoperation for failed initial segmental bone and joint prosthetic replacement is feasible and effective and can be done without jeopardizing subsequent patient and implant survival or without significantly affecting functional results compared with the values before reoperation.