الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Unicompartmental Knee Arthroplasty (UKA) has gained renewed interest in the past decade limited to lateral or medial compartments of the knee. The advantages of UKA over TKA are reduced blood loss, less peri-operative morbidity, faster recovery and rehabilitation and decreased post-operative pain. The purpose of this study is to evaluate and meta-analyze the variable outcomes of UKA.
Osteoarthritis (OA) is the most common cause of long-term disability in most populations over the age 65 years. Primary OA is rare before the age of 40 years but becomes increasingly common each decade thereafter. A report from the third national health and nutrition examination survey estimated that 37.4% of adults in the united states who are 60 years of age or older have radiographic evidence of the condition. Although OA is not a life-threatening disease, the morbidity associated with this condition is considerable; 80% of patients with OA have limitation of movement, and 25% have difficulty performing major activities of daily living. The economic burden of osteoarthritis may exceed $60 billion per year in the United States.
The patho-physiology of OA is complex and incompletely understood, although the hallmark of the disease is the loss of articular cartilage, with concomitant changes in the underlying bone. Many factors appear to be associated with the development of this condition, including injury, genetics, changes in tissue structure, and chondrocyte aging. Major trauma, such as an intra-articular fracture, clearly increases the risk of subsequent (post-traumatic) arthritis.
The anatomical features of knee OA include loss of articular cartilage, sclerosis of the subchondral bone, formation of osteophytes (or ”bone spurs”), and the presence of degenerative subchondral cysts. In some patients, there is clinically significant inflammation, including effusions, warmth, and synovitis that is visible during surgery. When OA of the knee becomes severe, joint deformities – most commonly, varus (”bowlegs”) or valgus (”knock-knees”) – can occur. On late stages of Knee OA surgical interference is considered a rule for treatment.
Currently, the primarily surgical methods of treating unicompartmental knee arthritis include high tibial osteotomy, Unicompartmental knee arthroplasty (UKA) and conventional Total Knee Arthroplasty (TKA). However, with the increasing concerns regarding the finite life span and post-operative functional recovery of these aforementioned procedures, the indications of UKA in the treatment of medial osteoarthritis were expanded. Moreover, many studies have reported excellent clinical outcomes after UKA, Including the reduction of post-operative pain, reduced blood loss, the correction of angle deformity (varus deformity) of the knee, the return of range of motion (ROM) and the improvement of clinical and functional scores. As it conserves bone stock better than TKA, UKA also provides patient with better kinesiology and faster recovery. Although some studies indicated that the revision rate of UKA is relatively high compared with that of TKA, the current long-term follow-ups of UKA show good clinical results in western populations.
In a significant proportion of patients, up to 47% by some estimates, disease is restricted to either the medial or the lateral tibiofemoral joints. These patients may be suitable for uni-compartmental knee arthroplasty (UKA). With UKA, only the parts of the knee affected by OA are replaced, and the cruciate ligaments and the remaining healthy joint surfaces are preserved. By retaining these structures, UKA restores the ligament-driven kinematics of the native knee. UKA requires a smaller incision than TKA and is associated with a shorter hospital stay and lower rates of infection, morbidity and mortality. As a result, it is more cost-effective than TKA. However, in unadjusted analyses, all major National Joint Registries (NJRs) report that the revision rate for UKA is two to three times higher than that for TKA.
This study performed a systemic review and a meta-analysis of the various literatures demonstrating the different clinical outcomes, pain and knee function pre and post-operatively following Oxford unicompartmental knee arthroplasty OUKA surgery in different patient categories such as standard, obese and highly active individuals, as well as it systematically review the effect of age on cost-effectiveness of OUKA surgery.
After recording the pooled estimate points of Oxford knee score OKS pre and post-operatively a meta-analysis was conducted and the results demonstrated that OUK prosthesis (phase III) showed significant improvement in the knee pain, function and range of motion, beside long survivorship of the implant over (5 – 12) years. More over the results also proved there were significant improvement of OKS and longevity of the prosthesis with obese and highly active individuals which conclude that there is no significant effect of obesity or high activity on OUKA and no longer considered a contra-indication for using the implant unlike what was previously believed. Eventually our study concluded that UKA is an economically attractive, cost-effective alternative in patients 65 years of age or older.