Ten- to 13-Year Results of Mobile Bearing Posterior-Stabilized Rotating-Platform Knee Implants, Reported by Nondesigner Surgeon.

BACKGROUND: Posterior-stabilized rotating-platform (PSRP) knee was designed with the purpose of improving postoperative flexion and stability. Its long-term performance has limited reports, which could show whether this purpose has been realized without deleterious effect. We report its long-term results at 10-13 years, of a previously studied cohort, evaluated longitudinally. METHODS: A total of 133 consecutive PSRP implants, selected for 118 patients were studied. Twenty-one patients (24 knees) were deceased and 11 patients (12 knees) were lost to follow-up after 10 years. Eighty patients (97 knees) completed clinical evaluation, of whom 78 patients (88 knees) also completed radiological evaluation. RESULTS: Mean flexion improved from 106.8° (30°-150°) to 127° (90°-155°). Forty-three percent patients could sit crosslegged, 32.5% could sit on floor, and 3.4% could squat. Mean knee subscore of Knee Society Score improved from 28 (1-59) to 96 (67-100). Mean function subscore improved from 53 (5-81) to 78 (-10 to 100). After 10 years, 5 patients had zero function score because of developing other debilitating medical illnesses. Twenty-one dead patients (24 knees), at their last follow-up (7.7 years), had satisfactory scores. No patient had spinout or revision. Radiologically, alignment was satisfactory and there was no osteolysis. Kaplan-Meier analysis showed 100% implant survival. CONCLUSION: PSRP design, evaluated after 10 years of implantation in selected patients, had 100% survival with good flexion. Addition of post and cam to the original rotating platform design has provided good stability without untoward effects of wear or osteolysis at 10-13 years.

A prospective randomized study in 20 patients undergoing bilateral TKA comparing midline incision to anterolateral incision.

BACKGROUND: Lateral flap numbness is a known side-effect of midline skin incision in total knee arthroplasty (TKA) and a cause of patient dissatisfaction. Anterolateral incision is an alternative approach which preserves the infrapatellar branches of the saphenous nerve and avoids numbness. Studies have compared both incisions, but in different patients. However, different patients may assess the same sensory deficit dissimilarly, because of individual variations in anatomy and healing responses. We compared the two incisions in the same patient at the same time, using an anterolateral incision on one knee and a midline incision on the other knee in simultaneous bilateral TKA. Other surgical steps including medial arthrotomy were idential. We also correlated subjective and objective findings. MATERIALS AND METHODS: Twenty patients were prospectively randomized. Sensory loss and skin healing were assessed at 6, 12 and 52 weeks. Subjective preference for the knee with less numbness was charted on Wald's Sequential Probability Ratio Test. Sensation scores for touch, vibration, static and moving two-point discrimination were measured. Scar healing was evaluated using the Patient and Observer Scar Assessment Scale (POSAS). Functional scores were measured. RESULTS: A statistically significant difference favoring knees with anterolateral incision was observed in patient preference at all assessment points and this correlated with sensation scores. A statistically significant difference was observed in POSAS score favoring knees with anterolateral incision at 6 and 12 weeks which became statistically insignificant at 1 year. Functional scores remained comparable. CONCLUSION: We recommend anterolateral incision as a safe and effective method to circumvent the problem of lateral flap numbness with midline incision. LEVEL OF EVIDENCE: I.

Surgical technique: Lateral retinaculum release in knee arthroplasty using a stepwise, outside-in technique.

BACKGROUND: Lateral release of a tight lateral retinaculum in a TKA is intended to correct patellar maltracking but the widely used inside-out technique has associated risks. We describe an alternate stepwise outside-in technique, with titrated release intended to maximize the chance of preserving the superior lateral genicular artery (SLGA). DESCRIPTION OF TECHNIQUE: Patellar maltracking was judged by a no-thumb technique and graded as I and Ia: normal and near normal tracking; II: patella tilted; III: patella subluxed; or IV: patella dislocated. Outside-in release was performed in three progressive steps. Step-1 release was from the midpatella to the upper tibial border, Step-2 release was from the midpatella to the proximal pole of the patella, and Step-3 release was proximal to the superior pole of the patella with sectioning of the SLGA. METHODS: We retrospectively reviewed records of 1884 patients operated on between 2002 to 2008. Two hundred five patients (11%) had lateral release performed, and 177 of those 205 patients (86%) were reviewed. Patellofemoral function was assessed clinically by The Knee Society score. Radiographs were examined for patellar tilt, shift, and avascular necrosis. The minimum followup was 22 months (median 48 months; range, 22-105 months). RESULTS: The SLGA was preserved in 155 (76%) patients. At last followup, no patient had patellar maltracking, patellar fracture, or avascular necrosis. Six of 177 (3%) patients had anterior knee pain. Female patients and high-flex components had a higher incidence of release and midvastus arthrotomy had a lower incidence of release. CONCLUSIONS: Stepwise release of the lateral retinaculum by an outside-in technique allowed minimum necessary retinacular release, preserving the SLGA in 76% of patients. No complications were seen at followup with functional and radiographic examinations. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Most effective regimen of tranexamic acid in knee arthroplasty: a prospective randomized controlled study in 240 patients.

BACKGROUND: The antifibrinolytic tranexamic acid reduces surgical blood loss, but studies have not identified an optimal regimen. QUESTIONS/PURPOSES: We studied different dosages, timings, and modes of administration to identify the most effective regimen of tranexamic acid in achieving maximum reduction of blood loss in TKA. METHODS: We prospectively studied five regimens (four intravenous, one local; 40 patients each) with a control group (no tranexamic acid). The four intravenous (10-mg/kg dose) regimens included (1) intraoperative dose (IO) given before tourniquet deflation, (2) additional preoperative dose (POIO), (3) additional postoperative dose (IOPO), and (4) all three doses (POIOPO). The fifth regimen was a single local application (LA). Two independent parameters of drain loss and total blood loss, calculated by the hemoglobin balance method, were evaluated statistically. RESULTS: Both parameters were reduced in all five regimens as against the control. A significant reduction in drain loss was seen in the POIO, IOPO, and POIOPO groups whereas total blood loss was significantly reduced in the POIO, POIOPO, and LA groups. The POIOPO group had the least drain loss (303 mL) and least total blood loss (688 mL). The IO group had the greatest drain loss and the IOPO group the greatest total blood loss. CONCLUSIONS: Single-dose tranexamic acid did not give effective results. The two-dose regimen of POIO was the least amount necessary for effective results. When compared against the control, this regimen produced reduction of drain loss and total blood loss, whereas the IOPO regimen did not. The three-dose regimen of POIOPO produced maximum effective reduction of drain loss and total blood loss.

High-flex rotating platform knee implants: two- to 6-year results of a prospective study.

We prospectively enrolled 48 patients (53 knees), scheduled for high-flex posterior-stabilized rotating platform knee implant arthroplasty (PFCΣRPF) to our study. Performance of this implant, introduced in 2005, has been reported upon only up to 2 years. We report its 2- to 6-year postoperative clinical and radiographic results in 47 patients (52 knees). Mean Knee Society score improved from 35.7 to 96. Mean function score improved from 55.2 to 90.6. Postoperative knee flexion averaged 130° (95°-155°), 81% patients could sit cross legged, 53% could sit on floor, and 21% could squat. Kaplan-Meier survival rate was 100% at average 50.2 months (26-72 months). No patient had any spin-out of rotating bearing. Supervised radiographs were analyzed, which showed no osteolysis or component loosening.

To use or not to use continuous passive motion post-total knee arthroplasty presenting functional assessment results in early recovery.

Continuous passive motion (CPM), though of doubtful value, is yet routinely practiced post-total knee arthroplasty (TKA). We prospectively distributed 84 patients with TKA to 1 of the 3 standard rehabilitation regimes: no-CPM, 1-day-CPM, and 3-day-CPM. We recorded a unique "Timed up and go" test besides pain, Western Ontario and McMaster Universities (WOMAC), short form-12 (SF-12), range of motion, knee and calf swelling, and wound healing parameters. Our standardized and elaborate measurements preoperatively and on postoperative days 3, 5, 14, 42, and 90 showed no statistically significant difference among the 3 groups in each parameter. We concluded that CPM gives no benefit in immediate functional recovery post-TKA, and in fact, the postoperative knee swelling persisted longer. We have since then discontinued its use in our patients without any untoward effect.

Five- to eight-year results of a prospective study in 118 arthroplasties using posterior-stabilized rotating-platform knee implants.

We prospectively enrolled 118 patients (133 knees) whose arthroplasties were performed using posterior-stabilized rotating-platform knee implants. Introduced in year 2000, this implant's performance beyond 5 years is not reported on, to date. We present 5- to 8-year (average, 6.5 years) results of 118 posterior-stabilized rotating-platform knee arthroplasties. Kaplan-Meier survival rate was 100%, considering revision or the need for it as the end point. Mean Knee Society Score improved from 27 (range, 1-54) to 96 (range, 54-100). Mean function score improved from 51 (range, 5-81) to 83 (range, 0-100). No patient had spin-out of rotating bearing or osteolysis. Postoperatively, knee flexion averaged 120° (range, 80°-155°), 34% patients achieved more than 130° flexion, and 67% patients could sit cross legged. Only 5% patients presented with patellofemoral symptoms.

WHO Class of Obesity Influences Functional Recovery Post-TKA.

BACKGROUND: No study in the literature has compared early functional recovery following total knee arthroplasty (TKA) in the obese with the nonobese using World Health Organization (WHO) classes of obesity. Our aim was to compare functional scores and flexion post-TKA in each class of obesity as per WHO classification against a matched control group of nonobese patients. METHODS: Records of 885 consecutive primary TKA patients (919 knees) operated by a single surgeon were reviewed. The first 35 knees in each class I, class II and class III obesity group during the study period were then matched with a similar number of knees in nonobese TKA patients during the same period. Functional scores recorded pre- and postoperatively at 3 months and 1 year were Western Ontario and McMaster Osteoarthritis Index (WOMAC), Short-Form Health Survey (SF-12) score, and Knee Society Score (KSS). RESULTS: There was no difference in any parameter between the class I obese and matched nonobese at any assessment point. In the class II obese, as compared to the nonobese, there was no difference in any parameter preoperatively and 3 months postoperatively. However, 1 year postoperatively, the SF-12 physical subscore was lower in the class II obese than the nonobese (44.7 vs. 48.6, p = 0.047) and the WOMAC score was significantly higher (15.8 vs. 9.7, p = 0.04). In the class III obese, the WOMAC score was significantly higher than the nonobese (58.1 vs. 44.3, p < 0.001 preoperatively; 15.7 vs. 8.1, p = 0.005 at 1 year) and KSS was significantly lower (83.5 vs. 96.5, p = 0.049 preoperatively; 172 vs. 185; p = 0.003 at 1 year). Knee flexion was significantly lower in the class III obese than the nonobese (95 vs. 113; p < 0.001 preoperatively; 120 vs. 127; p = 0.002 at 1 year). CONCLUSIONS: The class I obese can expect good early and late functional recovery as the nonobese. The class II obese can expect comparable early functional recovery as the nonobese but their late function may be lesser. The class III obese would have poorer functional scores and lesser knee flexion postoperatively compared to the nonobese. However, compared to their own preoperative status, there is definite improvement in function and knee flexion.

Optimizing effectivity of tranexamic acid in bilateral knee arthroplasty - A prospective randomized controlled study.

INTRODUCTION: Tranexamic acid (TEA) is used in reducing surgical blood loss. Literature shows no optimal regimen recommended for Bilateral Total Knee Arthroplasty (TKA). We evaluated three TEA regimens differing in dosage, timing and mode of administration in bilateral TKA to identify the most effective regimen to reduce blood loss. METHODS: We prospectively studied three TEA regimens (25 patients each) as follows: (1) two intraoperative, intravenous doses (IOIO), (2) two intraoperative local applications (LALA), and (3) one preoperative plus two intraoperative, intravenous doses (POIOIO). Two independent parameters of drain loss and total blood loss, calculated by the hemoglobin balance method were statistically evaluated. RESULTS: Mean drain loss was least (412.9ml) in the POIOIO group, greatest (607.2ml) in the IOIO group and LALA group in between (579.4ml), with a statistically significant difference among them (p=0.0022). On paired evaluation, the drain loss in the POIOIO group was significantly less as compared to the other two groups, whereas the difference between IOIO and LALA was not significant. Mean total blood loss was least in the POIOIO group (1207ml) and greatest in LALA group (1270ml). The difference among the groups was not statistically significant (p=0.80). There was no incidence of any thromboembolic phenomenon. On correlation with our study on Most Effective Regimen in Unilateral TKA, both results were found to substantiate each other.

Patient specific implants: scope for the future.

"Patient Specific" technology introduced in last 5 years, slowly gained popularity but has currently plateaued. We have a number of studies on patient specific instruments where they have been compared with conventional jigs in total knee arthroplasty and reported to have no clear additional benefits. This review discusses their intraoperative and postoperative advantages/disadvantages and cost effectiveness and provides a synopsis in light of current literature. Patient specific implants are not freely available yet, and there is no scientific literature reporting on their use in clinical practice.

Periprosthetic patellar fracture fixation using suture anchors.

Treatment of type II periprosthetic patellar fractures presents difficulties in decision-making particularly when displacement is greater than 10 mm. Poor results have been reported with internal fixation, whereas conservative management has been associated with a high incidence of extensor lag. This article reports a patient with a displaced type II patellar fracture following total knee arthroplasty. One month after undergoing total knee arthroplasty, a 72-year-old man presented to the emergency department with difficulty walking. Physical examination revealed an extensor lag with a palpable defect in the extensor mechanism. Radiographs showed a transverse, comminuted fracture through the distal third of the patella with a separation of approximately 15 mm. The patient underwent surgery, at which time the patellar component was found to be intact and well fixed to the proximal fragment. Three suture anchors were introduced into the proximal fragment through the fracture site. Tunnels were drilled in the distal fragment (through the fracture gap) corresponding to the location of the anchors; the sutures were threaded through these tunnels. Anatomical reduction was achieved with towel clips, and the sutures were tied at the distal pole. After the knots were tied, anatomical reduction was maintained, and the sutures were additionally used as cerclage around the patella. One year postoperatively, the fracture showed union, and the patient had good range of motion with no extensor lag. No patellar subluxation, avascular necrosis, or refracture occurred.

Influence of bilateral sequential total knee arthroplasty on functional recovery.

BACKGROUND: Main concerns of patients undergoing bilateral surgery is the quantum of pain and the progress of functional recovery. We studied functional recovery in terms of pain, range of motion (ROM), SF12, WOMAC scores and a unique TUG (timed up and go) test for patients undergoing unilateral total knee arthroplasty (U/L-TKA) and sequential bilateral total knee arthroplasty (B/L-TKA). MATERIALS AND METHODS: Three groups of 77 consecutive patients (91 knees) were retrospectively compared. They were B/L TKA group (28 knees: 14 patients), Unilateral TKA group with contralateral knee nonoperated i.e., U/L-TKA group (42 knees) and Unilateral TKA with contralateral TKA already done i.e., U/L + C/L TKA group (21 knees). Patients were assessed preoperatively and on postoperative days 3, 5, 14, 42, 90 and 1 year. RESULTS: The WOMAC score was statistically better preoperatively in the U/L + C/L TKA group, and SF12 MCS score was statistically better preoperatively in the B/L-TKA group. The TUG test time in the B/L-TKA group was statistically longer on days 3 and 5 as compared to other groups and became comparable by day 14. The TUG score became better than the preoperative value by day 42 in the B/L-TKA group, which took 90 days in other groups. CONCLUSION: The early functional recovery of bilateral TKA patient lags behind that of unilateral TKA patient for the first 5 days, becomes equal by the 14(th) day and remains equal till 1 year after surgery. Bilateral TKA patients regain their preoperative functional status by 6 weeks against 3 months for unilateral TKA. The operative status of the contralateral knee makes no difference to early functional recovery after unilateral TKA. With bilateral TKA, there is no difference in pain and ROM parameters.

Mid term results of LCS knee: The Indian experience.

BACKGROUND: The low contact stress rotating platform (LCS RP) knee (DePuy Orthopedics, Inc, Warsaw, Indiana), in use for last four decades in Western population, is reported to have a survival of more than 95% at 15 to 20 years. The reported Indian experience of this knee is limited to 5 years. Our aim was to report the clinical and radiological results of the LCS RP TKA design in the Indian population with a minimum followup of 10 years. MATERIALS AND METHODS: Fifty-five LCS knees (45 patients) operated between February 1997 and October 2001 were evaluated retrospectively. LCS design was generally selected if the patient was young (≤65 years of age), active and had no severe deformity. There were 40 female (88.9%) and 5 male (11.1%) patients; 47 knees had osteoarthritis (85.5%) and 8 knees had rheumatoid arthritis (14.5%). Knee Society Scores (KSS) and outcome questionnaire were filled at followup and radiographs were analyzed using Knee Society radiographic evaluation and scoring system. RESULTS: Of 45 patients (55 knees) enrolled, 37 patients (44 knees; 80%) were available for followup at 10 years. Average age was 59.6 years (range 40 to 77). Minimum followup was 10 years (average 12.3 years; range 10 to 15.3 years.). Three knees (6.8%) had been revised, one each for aseptic loosening, bearing dislocation and infection. Mean preoperative KSS of 33 improved to 91 postoperatively. Mean preoperative functional score of 45 improved to 76 postoperatively. Mean preoperative flexion of 113° (90°-140°) reduced to 102° (80°-135°) postoperatively. Erratic femoral rollback and tighter flexion gap to prevent spin out are the probable factors for decreased postoperative range of motion. Five (12%) patients could sit cross-legged and sit on the floor. Anterior knee pain was present in 4.6% (2/44 knees). The survival was 93.2% at 12.3 years. One patient (1.8%) had spin-out of the rotating bearing. No knee had osteolysis or progressive radiolucent lines on X-rays. CONCLUSION: LCS implant has given good survival (93.2% at 12.3 years) with low rates of spin-out and anterior knee pain and no incidence of osteolysis. Limited flexion post surgery (104°) with only 12% managing to sit cross legged on the floor is a drawback.