Manipulation after total knee arthroplasty.

BACKGROUND: Following total knee arthroplasty, some patients who fail to achieve >90 degrees of flexion in the early perioperative period may be considered candidates for manipulation of the knee under anesthesia. The purpose of this study was to assess the outcomes of manipulation following total knee arthroplasty. METHODS: One hundred and thirteen knees in ninety patients underwent manipulation for postoperative flexion of < or =90 degrees at a mean of ten weeks after surgery. Flexion was measured with a goniometer prior to total knee arthroplasty, at the conclusion of the operative procedure, before manipulation, immediately after manipulation, at six months, and at one, three, and five years postoperatively. RESULTS: Eighty-one (90%) of the ninety patients achieved improvement of ultimate knee flexion following manipulation. The average flexion was 102 degrees prior to total knee arthroplasty, 111 degrees following skin closure, and 70 degrees before manipulation. The average improvement in flexion from the measurement made before manipulation to that recorded at the five-year follow-up was 35 degrees (p < 0.0001, paired t test). There was no significant difference in the mean improvement in flexion when patients who had manipulation within twelve weeks postoperatively were compared with those who had manipulation more than twelve weeks postoperatively. Patients who eventually underwent manipulation had significantly lower preoperative Knee Society pain scores (more pain) than those who had not had manipulation (p = 0.0027). CONCLUSIONS: Manipulation generally increases ultimate flexion following total knee arthroplasty. Patients with severe preoperative pain are more likely to require manipulation.

Total hip arthroplasty with satin finish, tapered stems.

Subsidence of femoral hip prostheses with a rough surface has been associated with osteolysis and loosening. However, recent evidence has suggested that smooth-finish tapered stems may not incur these problems. An experimental monobloc satin finish, tapered femoral component was designed to subside within the cement. There were 49 femoral components implanted, and patients averaged a 1.8-mm subsidence at the prosthesis-cement interface with a follow-up of 6.76 years. There were no failures attributable to aseptic loosening at the cement-bone interface. This study supports the use of a satin finish, tapered femoral component in cemented total hip arthroplasty.

The AGC all-polyethylene tibial component: a ten-year clinical evaluation.

BACKGROUND: While high success rates have been achieved in association with other all-polyethylene tibial components, an alarming number of failures have occurred at our institution in association with the use of an all-polyethylene version of the AGC tibial component. The purpose of the present study was to describe the survival of the AGC all-polyethylene tibial component. METHODS: Five hundred and thirty-six AGC all-polyethylene tibial components were implanted in 405 patients and were followed over a ten-year period. The average age of the patients at the time of surgery was 70.3 years, the average weight was 78 kg, and the most common diagnosis was osteoarthritis (prevalence, 92.9%). A clinical and radiographic analysis was performed, Knee Society knee and function scores were determined, and Kaplan-Meier survivorship analysis was conducted. Failure was defined as aseptic loosening as evidenced by progressive radiolucent lines and/or revision due to aseptic loosening or collapse. RESULTS: A high rate of failure was noted in the early postoperative period, with a survival rate of 90.04% (95% confidence interval, 87.35% to 92.72%) after three years. At ten years, the survival rate was 68.11% (95% confidence interval, 57.57% to 78.65%). Fifty-eight (73.4%) of seventy-nine failures occurred in association with loosening or collapse of the bone beneath the medial tibial plateau. CONCLUSION: While some all-polyethylene tibial designs have been successful, the low success rate among knees treated with the AGC all-polyethylene tibial component suggests that the results associated with all-polyethylene tibial components are design-sensitive. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Predicting range of motion after total knee arthroplasty. Clustering, log-linear regression, and regression tree analysis.

BACKGROUND: Range of motion is a crucial measure of the outcome of total knee arthroplasty. The purpose of this study was to determine which factors are predictive of the postoperative range of motion. METHODS: We retrospectively studied 3066 patients (4727 knees) who had a primary total knee arthroplasty with the same type of implant at the same center between 1983 and 1998. Statistical clustering analysis paired with log-linear regression was used to determine groupings along continuous variables. Regression tree analysis was used to characterize the combinations of variables influencing the postoperative range of motion. The variables considered were preoperative and intraoperative flexion and extension, preoperative alignment, age, gender, and soft-tissue releases. RESULTS: Preoperative flexion was the strongest predictor of the postoperative flexion regardless of preoperative alignment. Other factors that were significantly related to reduced flexion were intraoperative flexion (p < 0.0001), gender (p < 0.0001), preoperative tibiofemoral alignment (p = 0.0005), age (p < 0.0001), and posterior capsular release (p < 0.0001). The removal of posterior osteophytes was related to the greatest increase in postoperative flexion in the group of patients with a varus tibiofemoral alignment preoperatively. CONCLUSIONS: The principal predictive factor of the postoperative range of motion was the preoperative range of motion. Removal of posterior osteophytes and release of the deep medial collateral ligament, the semimembranosus tendon, and the pes anserinus tendon in patients with large preoperative varus alignment and the attainment of a good intraoperative range of motion improved the likelihood that a good postoperative range of motion would be achieved.

Simultaneous bilateral, staged bilateral, and unilateral total knee arthroplasty. A survival analysis.

BACKGROUND: The rates of perioperative morbidity and mortality are areas of concern associated with simultaneous bilateral total knee replacement. The purpose of this paper was to compare the rates of morbidity and mortality and the clinical outcome in large groups of consecutive patients undergoing simultaneous bilateral total knee replacement, unilateral total knee replacement, or staged bilateral total knee replacement. METHODS: A total of 6200 total knee replacements, performed in 3998 patients between 1983 and 2000, consisted of 2050 simultaneous bilateral, 1796 unilateral, and 152 staged bilateral total knee replacements. A review of each group was conducted to compare the rates of morbidity and mortality, the survival of the prosthesis, and the clinical outcome. Kaplan-Meier survival analyses were performed with failure defined as revision because of aseptic loosening and as patient death. Complications and Knee Society scores were compared throughout the fifteen-year follow-up period (average, 4.3 years of follow-up). RESULTS: The unilateral group had significantly lower Knee Society scores than the simultaneous bilateral group (p < 0.0001 up to twelve years, and p = 0.0067 at fifteen years) across all postoperative time-intervals. The percentage of patients who had thrombophlebitis was significantly higher in the simultaneous bilateral group (0.9%) than in the unilateral group (0.3%) (p = 0.0326). No significant differences were found with regard to prosthetic failure, cardiac complications, and the rates of death in the three groups. Ten years postoperatively, the simultaneous bilateral group had a significantly higher rate of patient survival than did the unilateral group (78.6% compared with 72.0%) (p = 0.0062). CONCLUSIONS: The significantly higher rate of thrombophlebitis in the simultaneous bilateral group compared with that in the unilateral group may represent a greater risk to those patients. However, we believe that when there are adequate indications for bilateral total knee replacement, simultaneous bilateral arthroplasty is beneficial to patients, with a minimal increase in the risk of death or other complications compared with that associated with unilateral and staged procedures.

Total joint replacement in patients with dementia syndromes: a report of thirteen cases.

The hospital course and clinical outcomes of 14 joint replacement surgeries in 13 patients with dementia syndromes were evaluated. Eight patients were disoriented postoperatively. Complications included slow progress in physical therapy, getting out of bed unattended, aggressive behavior, pulling out an intravenous or Foley catheter, and falling out of bed. Three patients were unable to comprehend their movement restrictions, resulting in one dislocated hip from bending and twisting. Eleven of twelve joints available for follow-up were believed to be painless and functional. One patient was inactive due to fractures secondary to osteoporosis. Although complications arise from patients' disoriented status, total joint replacement relieves pain, and the patients' relatives indicated satisfaction with the results of the surgery. The family of a patient with dementia syndrome must be actively involved in all aspects of care after total joint replacement.

Simultaneous bilateral versus unilateral total hip arthroplasty an outcomes analysis.

This study compared the morbidity, mortality, and outcomes of 900 simultaneous bilateral total hip arthroplasties in 450 patients and 450 unilateral total hip arthroplasties. Pulmonary complications were significantly higher in the simultaneous bilateral group (1.6% vs 0.7%; P < .0312). Fourteen (3.1%) patients in the simultaneous bilateral group and 18 (4%) patients in the unilateral group died within the first postoperative year. Patients with mortality in the first postoperative year were significantly older (69.8 vs 62.3 years; P < .0012). Long-term patient survival, the prosthetic survival, and functional outcomes were not significantly different between groups. Simultaneous bilateral total hip arthroplasty has advantages where both hips are symptomatic and has less risk in younger patients with understanding of the increased risk of pulmonary complications.

Debate: simultaneous bilateral knee replacements: the outcomes justify its use.

The purpose of this paper is to assess the morbidity, mortality, and clinical outcome of simultaneous bilateral total knee arthroplasty. We reviewed 4100 simultaneous bilateral total knee replacements. The knees were subjected to two Kaplan-Meier survival analyses, with failure equal to revision for aseptic loosening and failure equal to patient death. Complications and Knee Society scores were considered. The average Knee Society knee score was 90 points 3 years postoperatively and 87 points 10 years postoperatively. The complication rates were as follows: deep infection (0.8%), superficial infection (0.3%), cardiac (6 arrhythmia, 5 congestive heart failure, 1 cardiac insufficiency, 3 complete heart block, 2 myocardial infarction and cardiac arrest, and 14 myocardial infarction only) (1.5%), intestinal ileus (0.5%), gastrointestinal ulcer (0.4%), thrombophlebitis (0.9%), cerebrovascular accident (0.3%), and urinary (1 BPH-obstruction, 4 renal failure, 2 transurethral resection of the prostate, 16 urinary tract infection, and 2 urinary retention/incontinence) (1.2%). The 10-year prosthesis survival probability was 98.3%. The 10-year patient survival probability was 78.6%. Twenty-five (1.2%) patients died within the first postoperative year. The patients who died within 1 year postoperatively were older than the rest of the group. Higher age and male gender were factors related to increased mortality. The complication rates and clinical outcomes were similar to unilateral total knee arthroplasty. With regard to death early in the postoperative course, simultaneous bilateral total knee arthroplasty may pose a greater risk to the patient than a unilateral procedure. However, the early deaths may be related to older age at the time of surgery.

Medial screws and cement: a possible mechanical augmentation in total knee arthroplasty.

The purpose of this study was to determine whether screws placed beneath the medial tibial plateau in cemented total knee arthroplasty helps prevent collapse of the medial tibia. A previous study found that the AGC all-polyethylene tibial component had a 14% rate of collapse of the medial subchondral region in the first postoperative year. Of 536 implanted AGC all-polyethylene tibial components, 20 had screws inserted beneath the medial tibial plateau. No AGC all-polyethylene tibial components with screws failed because of aseptic loosening or collapse of the medial tibial plateau. The study included 125 cemented metal-backed total knee arthroplasties with screws inserted beneath the medial tibial plateau. We also found 2 cases of collapse of the medial tibial plateau and 1 case of collapse on the lateral side. No revisions were performed. The placement of screws beneath the medial tibial plateau to fill large defects is an excellent precaution against collapse of the medial tibia.

Fat embolism in revision total hip arthroplasty.

Two patients developed fat embolism syndrome after revision of loose total hip arthroplasties (THAs). During both procedures, the prosthesis became rigidly fixed 1 to 1.5 cm before the expected level of fixation. After uncomplicated operative courses, Patient A remained obtunded and febrile for 2.5 days, and Patient B died 1 day postoperatively. In Patient A, a presumptive diagnosis of fat embolism syndrome was based on the postoperative course and a radiograph of the lungs. In Patient B, the diagnosis was confirmed by evidence of cerebral edema on a computed tomography scan of the head. Fat embolism syndrome is unexpected after revision THA because the fatty tissue is removed from the femoral canal during primary THA. In these 2 cases, the rigid fixation and multiple attempts to impact and subsequently to remove the prosthesis may have caused fat embolism syndrome.

Excisional arthroplasty for patellar loosening in total knee arthroplasty.

Four thousand two hundred eighty-seven cases of Anatomic Graduated Components total knee replacements with a cemented, single-peg, all-polyethylene patellar component were performed at our institution over the past 15 years. One hundred eighty cases of patellar component loosening were found. Eleven knees (0.3%) in 11 patients required isolated patellar component reoperation. In all cases, the patellar component was excised and not reimplanted. The average follow-up for the 11 patients was 2.2 years. Five had a complete minimum follow-up of 2 years following reoperation. Pain and function were improved. Complications included infection in 3 knees and extensor lag in 1 knee. Because of the complication rate associated with isolated patellar component excision caused by a loose patellar component, we recommend surgical removal of the patellar component only in cases of severe pain and/or prominence of the component.

Predicting range of motion after revision total knee arthroplasty: clustering and log-linear regression analyses.

The purpose of this study was to determine which variables affected the range of motion following revision total knee arthroplasty. These variables included preoperative flexion, intraoperative flexion, preoperative alignment, patient demographics, type of posterior soft-tissue release, previous prosthesis type, and prosthesis type used for revision of 355 total knee arthroplasties. Clustering and log-linear regression analyses were used to determine which variables were significantly related to the postoperative flexion. The mean preoperative and postoperative flexion were 100.5 degrees and 104.6 degrees. Low preoperative (<103 degrees) and intraoperative flexion (<117 degrees), young age (<44 years), and constrained and hinged prosthesis types were associated with diminished flexion. Higher preoperative and intraoperative flexion resulted in higher postoperative flexion. When comparing the results of this study to the results of a similar study of primary total knee arthroplasties, flexion improved less following revision than following primary total knee arthroplasty.