Should central osteophytes within the articular cartilage of the lateral compartment be considered when determining the indication of unicompartmental knee arthroplasty for medial osteoarthritis?

Patients with central osteophytes in the lateral compartment may be poor candidates for unicompartmental knee arthroplasty (UKA) for medial knee arthritis given the thin overlying articular cartilage above the central osteophytes that is inadequate for supporting weight-bearing after UKA. Therefore, attempts should be made to detect central osteophytes to confirm suitability for UKA.

Octacalcium Phosphate/Gelatin Composite (OCP/Gel) Enhances Bone Repair in a Critical-sized Transcortical Femoral Defect Rat Model.

Background: Bone grafting is widely used to treat large bone defects. A porous composite of a bioactive octacalcium phosphate material with gelatin sponge (OCP/Gel) has been shown to biodegrade promptly and be replaced with new bone both in animal models of a membranous bone defect and a long bone defect. However, it is unclear whether OCP/Gel can regenerate bone in more severe bone defects, such as a critical-size transcortical defect.

A Right Angle Guide for Distal Tuberosity Osteotomy With Medial Open Wedge High Tibial Osteotomy for Varus Knee Osteoarthritis.

Medial open wedge high tibial osteotomy (OWHTO) is usually performed with proximal tuberosity osteotomy or setting the osteotomy line proximal to the tuberosity. However, OWHTO can result in patellofemoral complications due to postoperative patella infera. A new OWHTO technique, biplanar osteotomy with a distal tuberosity osteotomy, was reported in 2004 to prevent postoperative patella infera.

Impact of simultaneous hydrolysis of OCP and PLGA on bone induction of a PLGA-OCP composite scaffold in a rat femoral defect.

Effect of the simultaneous hydrolysis of octacalcium phosphate (OCP) and poly (lactic-co-glycolic acid) (PLGA) was investigated on its osteoconductivity. PLGA soaked in phosphate buffered saline with 0%, 20%, and 40% OCP at 37°C for eight weeks indicated that when the OCP dose was increased, 1) the weight loss of PLGA increased, 2) the glass transition temperature of the PLGAs decreased, 3) the saturation degree in the saline moved to nearly saturated condition with respect to hydroxyapatite (HA) but was undersaturated with respect to OCP, and 4) OCP tended to convert to HA by X-ray diffraction and Fourier transform infrared spectroscopy. OCP/PLGA composites of 20% and 40% with more than 92% porosity were produced by combining OCP granules with 1,4-dioxane-solubilizing PLGA followed by lyophilization and then subjected to four- and eight-week in vivo implantation tests in 3 mm diameter rat femora defects.

Chemical Stability-Sensitive Osteoconductive Performance of Octacalcium Phosphate Bone Substitute in an Ovariectomized Rat Tibia Defect.

The purpose of this study was to investigate whether the chemical condition of osteoporotic serum affects the chemical stability of octacalcium phosphate (OCP) and its osteoconductive property. The in vitro chemical dissolution in osteoporotic ovariectomized (OVX)-simulated conditions was analyzed. OCP and its composite form with gelatin (OCP/Gel), containing specific amounts of OCP (either 17% or 44% by weight), were used as experimental materials.

Surgical Approach to Pigmented Villonodular Synovitis and Synovial Osteochondromatosis in Pathological Expansion of the Popliteus Bursa.

We orthopaedic surgeons are not familiar with the popliteus bursa. It is defined as the expansion in the synovial membrane of the posterolateral part of the knee that lies between the lateral meniscus and the tendon of the popliteus muscle. The popliteus bursa extends approximately 1 cm distal to the joint line and has 4 borders; the medial border is the peripheral margin of the lateral meniscus, the lateral border is the popliteus tendon, and the superior and inferior borders are formed by 2 fascicles.

Quality of life after staged bilateral total knee arthroplasty: a minimum five-year follow-up study of seventy-eight patients.

Purpose: Although many studies have been performed to evaluate the quality of life (QOL) and patient satisfaction after total knee arthroplasty (TKA), almost all evaluations were performed in patients after unilateral TKA or in patients after mixed unilateral and bilateral TKA. Accordingly, this study aimed to evaluate QOL after staged bilateral TKA.

Methods: A total of 78 patients who underwent staged bilateral TKA for varus knee osteoarthritis were included in this study.

The effect of morphine added to periarticular multimodal drug injection or spinal anesthesia on pain management and functional recovery after total knee arthroplasty.

Background: The efficacy of morphine added to periarticular multimodal drug injection (PMDI) for pain management after total knee arthroplasty (TKA) is controversial. Adding morphine to spinal anesthesia has reportedly improved pain relief for the first 24 h. We examined the effect of morphine added to PMDI or spinal anesthesia on pain management and functional recovery after TKA.

Preliminary results of managing large medial tibial defects in primary total knee arthroplasty: autogenous morcellised bone graft.

Purpose: This study reports a case series of 44 primary total knee arthroplasties (TKAs) using autogenous morcellised bone grafting for large (≥10-mm-deep) medial tibial defects, which are generally repaired using metal augmentation. The bone-grafting technique is described in detail and the radiological outcomes are presented.

Methods: A total of 44 TKAs were followed up for a mean period of 58 months (range 24-139 months).

Effect of resorption rate and osteoconductivity of biodegradable calcium phosphate materials on the acquisition of natural bone strength in the repaired bone.

The purpose of this study was to compare the biodegradation rate and quality of regenerated bone among four materials. A short time period of 8 weeks was chosen to examine early bone healing. The rod-shaped implants of commercially available two β-tricalcium phosphate (β-TCP) ceramics with porosity 60% and 71-80%, respectively, laboratory prepared octacalcium phosphate/gelatin composite (OCP/Gel), which has been proven to have a highly osteoconductive and biodegradable property in rat calvarial defect, and gelatin sponge (Gelatin) were implanted in rabbit tibia defect of 6 mm diameter and 7 mm depth for 2, 4 and 8 weeks.

Comparison of intraoperative anthropometric measurements of the proximal tibia and tibial component in total knee arthroplasty.

Background: Precise matching of the tibial component and resected bony surfaces and proper rotational implanting of the tibial component are crucial for successful total knee arthroplasty. We aimed to analyze the exact anthropometric proximal tibial data of Japanese patients undergoing total knee arthroplasty and correlate the measurements with the dimensions of current total knee arthroplasty systems.

Methods: A total of 703 knees in 566 Japanese patients who underwent total knee arthroplasty for osteoarthritis were included.

Femoral footprint of the popliteus tendon may be at the risk of damage during total knee arthroplasty.

Purpose: The present study focused on the prevalence of incidental excision of the femoral footprint of the popliteus tendon during total knee arthroplasty and its associated risk factors.

Methods: A total of 275 knee arthroplasties were performed for 226 patients with varus knee osteoarthritis. The status of the femoral footprint of the popliteus tendon was intraoperatively evaluated and classified into three groups (preserved, partially excised, and completely excised), and the prevalence of the excision was identified.

Evaluation of the size and position of the insertion of the anterior medial meniscus root in varus osteoarthritic knees.

Purpose: Recent studies have suggested radial displacement of the medial meniscus as a cause of varus knee osteoarthritis (OA). Two anatomical studies reported that such displacement may be associated with anterior insertion of the medial meniscus anterior horn. It was aimed to evaluate the location and area of this insertion in patients with advanced knee OA.

Autologous morselised bone grafting for medial tibial defects in total knee arthroplasty.

Purpose: To evaluate the outcome of autologous morselised bone grafting for a medial tibial defect of ≥10 mm deep in 45 total knee arthroplasties (TKAs).

Methods: 38 patients aged 46 to 85 (mean, 73) years underwent 45 TKAs and autologous morselised bone grafting for a medial tibial defect of ≥10 (range, 10-25) mm in depth by a single surgeon. In the first 19 TKAs, 2 resected subchondral bone plates from the lateral tibial plateau were driven into 2 gutters made on the floor of the medial tibial defect as bony support posts.

Quality of life after bilateral total knee arthroplasty determined by a 3-year longitudinal evaluation using the Japanese knee osteoarthritis measure.

Background: Recently, the Japanese knee osteoarthritis measure (JKOM), a new disease-specific and patient-derived quality of life (QOL) measure, has been developed. The objectives of this study were to longitudinally evaluate QOL assessed by JKOM and objective outcomes including knee society score (KSS), range of motion (ROM), and timed up and go test (TUG) of patients who underwent bilateral total knee arthroplasties (TKAs) for osteoarthritis; to evaluate correlations between JKOM and those objective outcomes; and to test our hypothesis that increased maximum flexion leads to better JKOM.

Methods: Forty patients with bilateral TKAs and ≥ 3-year follow-up were included.

Effect of addition of hyaluronic acids on the osteoconductivity and biodegradability of synthetic octacalcium phosphate.

The present study was designed to investigate whether three sodium hyaluronic acid (HyA) medical products, Artz(®), Suvenyl(®) and a chemically modified derivative of sodium HyA Synvisc(®), can be used as suitable vehicles for an osteoconductive octacalcium phosphate (OCP). OCP granules (300-500 μm diameter) were mixed with these sodium HyAs with molecular weights of 90 × 10(4) (Artz(®)), 190 × 10(4) (Suvenyl(®)) and 600 × 10(4) (Synvisc(®)) (referred to as HyA90, HyA190 and HyA600, respectively). OCP-HyA composites were injected using a syringe into a polytetrafluoroethylene ring, placed on the subperiosteal region of mouse calvaria for 3 and 6 weeks, and then bone formation was assessed by histomorphometry.

Incidental durotomy during lumbar spine surgery: risk factors and anatomic locations: clinical article.

Object: Incidental durotomy (dural tear) is a common complication of lumbar spine surgery. The purpose of this study was to clarify the anatomical location of and the specific causative factors for incidental durotomy during primary lumbar spine surgery.

Methods: The authors retrospectively reviewed 1014 consecutive cases involving patients (412 women and 602 men; mean age 57 years; age range 11-97 years) who underwent a surgical procedure for treatment of degenerative lumbar spinal disease at their institution between 2002 and 2008.

Mechanical stress-related calvaria bone augmentation by onlayed octacalcium phosphate-collagen implant.

Previous studies have suggested that the biodegradability of octacalcium phosphate-collagen (OCP/Col) composite by osteoclasts is accelerated in association with mechanical stress suffered by the host tissue around the implant. The present study was designed to investigate whether alleviation of mechanical stress restores the bone regenerative properties of OCP/Col, as previously shown in nonload-bearing sites. OCP/Col discs supported with a polytetrafluoroethylene (PTFE) ring, which has a higher modulus than OCP/Col, were implanted in a rat subperiosteal pocket for up to 12 weeks.

Effect of partial hydrolysis of octacalcium phosphate on its osteoconductive characteristics.

The present study was designed to investigate whether the stoichiometry of octacalcium phosphate OCP affects its osteoconductive and immune response characteristics in rat bone marrow. Those characteristics of synthetic, well-grown OCP but with a non-stoichiometric composition were compared with those of a slightly hydrolyzed OCP (low crystalline OCP: LC-OCP), the fully hydrolyzed apatitic product of OCP or biodegradable beta-tricalcium phosphate (beta-TCP) ceramic, by their implantation in rat tibia for 56 days. The physicochemical aspect of implants and biological responses were analyzed by X-ray diffraction, histomorphometry, immunohistochemistry and expression of mRNA around the implants.