There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Background: Total hip and total knee arthroplasties are well accepted as reliable and suitable surgical procedures to return patients to function. Health-related quality-of-life instruments have been used to document outcomes in order to optimize the allocation of resources. The objective of this study was to review the literature regarding the outcomes of total hip and knee arthroplasties as evaluated by health-related quality-of-life instruments.

Methods: The Medline and EMBASE medical literature databases were searched, from January 1980 to June 2003, to identify relevant studies. Studies were eligible for review if they met the following criteria: (1) the language was English or French, (2) at least one well-validated and self-reported health-related quality of life instrument was used, and (3) a prospective cohort study design was used.

Results: Of the seventy-four studies selected for the review, thirty-two investigated both total hip and total knee arthroplasties, twenty-six focused on total hip arthroplasty, and sixteen focused on total knee arthroplasty exclusively. The most common diagnosis was osteoarthritis. The duration of follow-up ranged from seven days to seven years, with the majority of studies describing results at six to twelve months. The Short Form-36 and the Western Ontario and McMaster University Osteoarthritis Index, the most frequently used instruments, were employed in forty and twenty-eight studies, respectively. Seventeen studies used a utility index. Overall, total hip and total knee arthroplasties were found to be quite effective in terms of improvement in health-related quality-of-life dimensions, with the occasional exception of the social dimension. Age was not found to be an obstacle to effective surgery, and men seemed to benefit more from the intervention than did women. When improvement was found to be modest, the role of comorbidities was highlighted. Total hip arthroplasty appears to return patients to function to a greater extent than do knee procedures, and primary surgery offers greater improvement than does revision. Patients who had poorer preoperative health-related quality of life were more likely to experience greater improvement.

Conclusions: Health-related quality-of-life data are valuable, can provide relevant health-status information to health professionals, and should be used as a rationale for the implementation of the most adequate standard of care. Additional knowledge and scientific dissemination of surgery outcomes should help to ensure better management of patients undergoing total hip or total knee arthroplasty and to optimize the use of these procedures.

Level of Evidence: Therapeutic study, Level III-3 (systematic review of Level-III studies). See Instructions to Authors for a complete description of levels of evidence.

Health-related quality of life in total hip and total knee arthroplasty. A qualitative and systematic review of the literature.

The knee meniscus: structure-function, pathophysiology, current repair techniques, and prospects for regeneration.

Study Design Prospective study with repeated measures. Objectives The overall goal of this investigation was to describe the time course of recovery of impairments and function after total knee arthroplasty (TKA), as well as to provide direction for rehabilitation efforts. We hypothesized that quadriceps strength would be more strongly correlated with functional performance than knee flexion range of motion (ROM) or pain at all time periods studied before and after TKA. Background TKA is a very common surgery, but very little is known regarding the influence of impairments on functional limitations in this population. Methods and Measures Forty subjects who underwent unilateral TKA followed by rehabilitation, including 6 weeks of outpatient physical therapy, were studied. Testing occurred at 5 time periods: preoperatively, and at 1, 2, 3, and 6 months after surgery. Test measures included quadriceps strength, knee ROM, timed up-and-go test, timed stair-climbing test, bodily pain, and general health and kn...

https://www.jospt.org/doi/pdf/10.2519/jospt.2005.35.7.424

Quadriceps Strength and the Time Course of Functional Recovery After Total Knee Arthroplasty

Background and purpose Very few studies have focused on patient characteristics that influence length of stay (LOS) in fast-track total hip (THR) and knee arthroplasty (TKR). The aim of this prospe...

Predictors of length of stay and patient satisfaction after hip and knee replacement surgery: fast-track experience in 712 patients.

We hypothesized that a pattern of decreasing postoperative length of stay (LOS) in the hospital could lead to an increased rate of manipulation after total knee arthroplasty (TKA). The decision to manipulate is based on the patient's ability to perform normal physical activities, which may in large part be dependent on adequate knee flexion (ie, range of motion [ROM]). Decreased exposure to physical therapy (as a result of decreased LOS) may be a contributing factor leading to impaired functional ROM in the 6-week postoperative period. We examined records from 745 patients (2 surgeons) who had a primary TKA from 1993 to 1996. At our institution, development and implementation of clinical pathways resulted in a significant decrease in the average LOS beginning in 1993. The average LOS in 1993 was 6.4 +/- 1.8 days (mean +/- SD) and progressively decreased to 4.4 +/- 1.0 days in 1996 (P < .0001). The rate of manipulation (patients manipulated at 6 weeks/total number of patients receiving TKA) was 6.0% in 1993 and increased to 11.3% (P = .09) in 1994, 13.5% (P = .02) in 1995, and 12.0% (P = .05) in 1996. In the period 1993-1996, patients requiring manipulation consistently had a lower ROM at discharge from the hospital (69.0 +/- 10 degrees, n = 67, P < .0001) compared with patients not requiring manipulation (80.7 +/- 10.6 degrees, n = 542). The relatively low frequency and charge for manipulation may justify the decision to decrease patient exposure to physical therapy through reduction in LOS. As efforts to decrease LOS continue, however, we must aggressively manage patients and provide adequate exposure to inpatient and outpatient physical therapy to ensure optimal ROM results.

Relationship between length of stay and manipulation rate after total knee arthroplasty

The purpose of this study was to determine if intra-articular injection of morphine or bupivacaine significantly decreased postoperative pain as well as the use of intravenous narcotics for pain relief in patients undergoing total knee arthroplasty (TKA). In a prospective, double-blind, randomized fashion, 105 patients undergoing TKA were divided into the following 4 groups defined by the intra-articular injection they received: group 1 (n = 27) received saline solution, group 2 (n = 26) received morphine sulfate (5 mg), group 3 (n = 24) received bupivacaine (50 mg), and group 4 (n = 28) received a combination of morphine sulfate and bupivacaine. The injections were administered immediately after wound closure by the Hemovac drainage tubing that remained clamped for 45 minutes after surgery to allow for absorption. Before surgery and at 2, 4, 6, 24, and 48 hours after surgery, pain intensity was recorded using a visual analog scale. Postoperative supplemental intravenous morphine and/or meperidine was administered via a patient-controlled analgesia device, and 24-hour drug usage was tabulated. Results were suggestive of a modest short-term reduction in pain scores in the morphine and bupivacaine treatment groups compared with placebo (saline); however, results were statistically significant only at 4 hours because of the great variability in the pain score data. The total amount of postoperative pain medication used in the first 24 hours after surgery was not statistically significant between the 4 treatment groups. Thus, the results put into question the benefit of postoperative intra-articular administration of morphine or bupivacaine in patients undergoing TKA.

Intra-articular morphine and/or bupivacaine in the management of pain after total knee arthroplasty

Calcium crystals exist in the knee joint fluid of up to 65% of osteoarthritis (OA) patients and the presence of these calcium crystals correlates with the radiographic evidence of hyaline cartilaginous degeneration. This study sought to examine calcium deposition in OA meniscus and to investigate OA meniscal cell-mediated calcium deposition. The hypothesis was that OA meniscal cells may play a role in pathological meniscal calcification. Studies were approved by our human subjects Institutional Review Board. Menisci were collected during joint replacement surgeries for OA patients and during limb amputation surgeries for osteosarcoma patients. Calcium deposits in menisci were examined by alizarin red staining. Expression of genes involved in biomineralization in OA meniscal cells was examined by microarray and real-time RT-PCR. Cell-mediated calcium deposition in monolayer culture of meniscal cells was examined using an ATP-induced 45calcium deposition assay. Calcium depositions were detected in OA menisci but not in normal menisci. The expression of several genes involved in biomineralization including ENPP1 and ANKH was upregulated in OA meniscal cells. Consistently, ATP-induced calcium deposition in the monolayer culture of OA meniscal cells was much higher than that in the monolayer culture of control meniscal cells. Calcium deposition is common in OA menisci. OA meniscal cells calcify more readily than normal meniscal cells. Pathological meniscal calcification, which may alter the biomechanical properties of the knee meniscus, is potentially an important contributory factor to OA.

/pdf/calcium-deposition-in-osteoarthritic-meniscus-and-meniscal-1svq8skvat.pdf

Calcium deposition in osteoarthritic meniscus and meniscal cell culture.

Fracture of the tibial post in posterior cruciate-substituting total knee arthroplasty has been described in several reports. Additionally, wear of the cam and post mechanism, including polyethylene debris generation and osteolysis of the peri-implant bone stock as been described. Users of a cam and post type posterior stabilized total knee arthroplasty are also familiar with the rare occurrence of the "patellar clunk syndrome," in which suprapatellar fibrous nodular scar tissue becomes entrapped in the intercondylar box of the femoral component as the knee extends from the flexed position and produces a palpable and sometimes audible "clunk." This condition is easily managed with arthroscopic excision of the scar tissue. A small series of 5 patients who presented with symptoms of a patellar clunk syndrome but who in fact had a fracture of the tibial post causing subluxation of the femur on the tibia is presented. The diagnostic characteristics that will help differentiate between the 2 problems is highlighted.

Fracture of the polyethylene tibial post in a posterior cruciate-substituting total knee arthroplasty mimicking patellar clunk syndrome: a report of 5 cases.

Menisci play a vital role in load transmission, shock absorption and joint stability. There is increasing evidence suggesting that OA menisci may not merely be bystanders in the disease process of OA. This study sought: 1) to determine the prevalence of meniscal degeneration in OA patients, and 2) to examine gene expression in OA meniscal cells compared to normal meniscal cells. Studies were approved by our human subjects Institutional Review Board. Menisci and articular cartilage were collected during joint replacement surgery for OA patients and lower limb amputation surgery for osteosarcoma patients (normal control specimens), and graded. Meniscal cells were prepared from these meniscal tissues and expanded in monolayer culture. Differential gene expression in OA meniscal cells and normal meniscal cells was examined using Affymetrix microarray and real time RT-PCR. The grades of meniscal degeneration correlated with the grades of articular cartilage degeneration (r = 0.672; P < 0.0001). Many of the genes classified in the biological processes of immune response, inflammatory response, biomineral formation and cell proliferation, including major histocompatibility complex, class II, DP alpha 1 (HLA-DPA1), integrin, beta 2 (ITGB2), ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), ankylosis, progressive homolog (ANKH) and fibroblast growth factor 7 (FGF7), were expressed at significantly higher levels in OA meniscal cells compared to normal meniscal cells. Importantly, many of the genes that have been shown to be differentially expressed in other OA cell types/tissues, including ADAM metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS5) and prostaglandin E synthase (PTGES), were found to be expressed at significantly higher levels in OA meniscal cells. This consistency suggests that many of the genes detected in our study are disease-specific. Our findings suggest that OA is a whole joint disease. Meniscal cells may play an active role in the development of OA. Investigation of the gene expression profiles of OA meniscal cells may reveal new therapeutic targets for OA therapy and also may uncover novel disease markers for early diagnosis of OA.

/pdf/analysis-of-meniscal-degeneration-and-meniscal-gene-g72ma6c1u0.pdf

David R. Mauerhan

Papers

Relationship between length of stay and manipulation rate after total knee arthroplasty

Intra-articular morphine and/or bupivacaine in the management of pain after total knee arthroplasty

Calcium deposition in osteoarthritic meniscus and meniscal cell culture.

Fracture of the polyethylene tibial post in a posterior cruciate-substituting total knee arthroplasty mimicking patellar clunk syndrome: a report of 5 cases.

Analysis of meniscal degeneration and meniscal gene expression