Aims

The aim of this study was to investigate the distribution of phenotypes in Asian patients with end-stage osteoarthritis (OA) and assess whether the phenotype affected the clinical outcome and survival of mechanically aligned total knee arthroplasty (TKA). We also compared the survival of the group in which the phenotype unintentionally remained unchanged with those in which it was corrected to neutral.

Aims

The study aimed to assess the clinical outcomes of arthroscopic debridement and partial excision in patients with traumatic central tears of the triangular fibrocartilage complex (TFCC), and to identify prognostic factors associated with unfavourable clinical outcomes.

Primary care physicians rely on radiology reports to confirm a scoliosis diagnosis and inform the need for spine specialist referral. In turn, spine specialists use these reports for triage decisions and planning of care. To be a valid predictor of disease and management, radiographic evaluation should include frontal and lateral views of the spine and a complete view of the pelvis, leading to accurate Cobb angle measurements and Risser staging. The study objectives were to determine 1) the adequacy of index images to inform treatment decisions at initial consultation by generating a score and 2) the utility of index radiology reports for appropriate triage decisions, by comparing reports to corresponding images.

We conducted a retrospective chart and radiographic review including all idiopathic scoliosis patients seen for initial consultation, aged three to 18 years, between January 1-April 30, 2021. A score was generated based on the adequacy of index images to provide accurate Cobb angle measurements and determine skeletal maturity (view of full spine, coronal=two, lateral=one, pelvis=one, ribcage=one). Index images were considered inadequate if repeat imaging was necessary. Comparisons were made between index radiology report, associated imaging, and new imaging if obtained at initial consultation. Major discrepancies were defined by inter-reader difference >15°, discordant Risser staging, or inaccuracies that led to inappropriate triage decisions. Location of index imaging, hospital versus community-based private clinic, was evaluated as a risk factor for inadequate or discrepant imaging.

There were 94 patients reviewed with 79% (n=74) requiring repeat imaging at initial consultation, of which 74% (n=55) were due to insufficient quality and/or visualization of the sagittal profile, pelvis or ribcage. Of index images available for review at initial consult (n=80), 41.2% scored five out of five and 32.5% scored two or below. New imaging showed that 50.0% of those patients had not been triaged appropriately, compared to 18.2% of patients with a full score. Comparing index radiology reports to initial visit evaluation with <60 days between imaging (n=49), discrepancies in Cobb angle were found in 24.5% (95% CI 14.6, 38.1) of patients, with 18.4% (95% CI 10.0, 31.4) categorized as major discrepancies. Risser stage was reported in only 14% of index radiology reports. In 13.8% (n=13) of the total cohort, surgical or brace treatment was recommended when not predicted based on index radiology report. Repeat radiograph (p=0.001, OR=8.38) and discrepancies (p=0.02, OR=7.96) were increased when index imaging was obtained at community-based private clinic compared to at a hospital. Re-evaluation of available index imaging demonstrated that 24.6% (95% CI 15.2, 37.1) of Cobb angles were mis-reported by six to 21 degrees.

Most pre-referral paediatric spine radiographs are inadequate for idiopathic scoliosis evaluation. Standardization of spine imaging and reporting should improve measurement accuracy, facilitate triage and decrease unnecessary radiation exposure.

Introduction

Cobalt chrome femoral head has been used widely in total hip arthroplasty and has shown favorable outcome. However, there is still of concern of potential metal toxicity from the wear debris. In the other hand, titanium is well known for its biocompatibility but it is not used in bearing surface of arthroplasty due to its brittleness. Recently, coating of the prosthesis using plasma electrolytic oxidation (PEO) has shown favorable surface protection. Thus, in this study, we tried to find out whether the PEO coating on the titanium surface would provide surface protection.

Background

Humeral retroversion is variable among individuals, and there are several measurement methods. This study was conducted to compare the concordance and reliability between the standard method and 5 other measurement methods on Twodimensional (2D) computed tomography (CT) scans.

Purpose

There are still some controversies over the routine use of negative suction drainage after primary total hip arthroplasty (THA). In this study we are to know the benefits of new suction drainage management strategy after primary THA.

Introduction

Ultra high molecular weight polyethylene (UHMWPE) has been used successfully as a bearing material in hip, knee, and shoulder joint replacements. However, there are problems to cause a failure in UHMWPE component, which are wear behavior and creep deformation. Continuous bearing motion and dynamic load have occurred to UHMWPE wear debris caused osteolysis in periprosthetic tissue and to plastic deformation of joint component, and subsequent aseptic loosening of components. Therefore, many studies have being carried out in order to reduce wear debris and to improve mechanical strength from UHMWPE, and there is tremendous improvement of mechanical property in UHMWPE from gamma irradiated conventional UHMWPE (GIPE), highly crosslinked PE (XLPE), and XLPE with vitamin E1, 2. Friction has a significant one of the factors effect on the wear and creep deformation. In this study, the short-term frictional behaviors of three typical types of GIPE, remelted XLPE (R-XLPE), and s annealed XLPE (A-XLPE), and XLPE with Vitamin E against Co-Cr alloy were compared under three levels of contact pressures which occured in hip, knee, and shoulder joints.

Introduction

Total hip arthroplasty (THA) is the most common surgery performed for complications of bipolar arthroplasty. The present study evaluated the functional results and complications associated with this surgery.

Introduction

Cementless grit-blasted tapered-wedge titanium femoral stems are being used with increasing frequency in hip arthroplasty because of excellent long-term outcomes. However, periprosthetic femur fracture is a potentially worrisome phenomenon in these types of femoral stems. The aim of this study is to report the incidence of stem loosening in association with periprosthetic femur fractures following hip arthroplasty using cementless grit-blasted tapered-wedge stems.

Introduction

Micro-arc oxidation (MAO) is an electrochemical method used to treat metal surfaces. It provides nanoporous pits, and thick oxide layers, and incorporates calcium and phosphorus into the coating layer of titanium alloy. This modification on the surface of titanium alloy by MAO coating would improve the ability of cementless stems to osseointegrate. In spite of these structural and chemical advantages, clinical study of total hip arthroplasty (THA) using MAO coated stem has not yet been reported. In this study, we evaluated the clinical and radiographic results associated with cementless grit-blasted tapered-wedge stems that were identical in geometry but differed with regard to surface treatment with or without MAO coating.

We performed a retrospective study to determine the effect of osteoporosis on the functional outcome of osteoporotic distal radial fractures treated with a volar locking plate. Between 2009 and 2012 a total of 90 postmenopausal women with an unstable fracture of the distal radius treated with a volar locking plate were studied. Changes in the radiological parameters of 51 patients with osteoporosis (group 1, mean age 66.9, mean T-score –3.16 (sd 0.56)) were not significantly different from those in 39 patients without osteoporosis (group 2, mean age 61.1, mean T-score –1.72 (sd 0.57)). The mean Disabilities of the Arm, Shoulder and Hand (DASH) score at final follow-up was 11.5 (sd 12.2) in group 1 and 10.5 (sd 13.25) in group 2. The mean modified Mayo wrist score at final follow-up was 79.0 (sd 14.04) in group 1 and 82.6 (sd 13.1) in group 2. However, this difference was not statistically significant (p = 0.35 for DASH score, p = 0.2 for modified Mayo wrist score). Univariable and multivariable logistic regression analysis showed that only the step-off of the radiocarpal joint was related to both a poor DASH and modified Mayo wrist score. Pearson’s correlation coefficient showed a weak negative relationship only between the T-score and the change in volar tilt (intraclass coefficient –0.26, p = 0.02).

We found that osteoporosis does not have a negative effect on the functional outcome and additional analysis did not show a correlation between T-score and outcome.

Cite this article: Bone Joint J 2015;97-B:229–34.

Constrained condylar knee (CCK) prosthesis offers an implant option for complex revision total knee arthroplasties in which stable varus-valgus constraint as well as rotational control is needed for severe bone defect and ligament insufficiency. The aim of this study was to evaluate the clinical and radiological outcome of CCK prosthesis in revision TKA.

Fify-one revision TKAs performed using CCK prosthesis between Jan. 1998 and Feb. 2006 were performed. The mean follow-up period was 5 years and 3 months (2 to 9 years) and the interval between initial and revision TKA was 8 years (4 months to 21 years). The mean age was 67 years. Range of motion (ROM), knee society (KS) score, hospital for special surgery (HSS) score, complication rate and failure rate was evaluated. The tibiofemoral angle and radiolucent line was also evaluated on plain radiograph.

The mean ROM improved from 81.9° to 102°. The mean KS score improved from 49.3° to 79.7°, and KS function score from 50.3 to 71.0 (P< .001). The mean HSS score improved from 50.7 to 78.7 (P< .001). Tibiofemoral angle improved from valgus 3.1° to valgus 5.6° (P< .001). Radiolucent line more than 2mm was observed around 4 femoral and 4 tibial components. Complications including 1 skin necrosis, 1 tibial tubercle nonunion, 2 infections, 3 periprosthetic fractures and 5 arthrofibrosis were observed. Overall rating was excellent or good in 88% at the last follow up.

Revision TKA using CCK prosthesis showed comparable results with other reports in average 5 years follow-up.

The aim of this study was to evaluate the rotational axis of the tibia and the association of its axis to tibial coronal alignment after TKR.

TKRs were performed using navigated mobile bearing system (40 knees), conventional mobile bearing (48 knees) and conventional fixed bearing (40 knees) and preoperative and postoperative CT scans were assessed using 3D image reconstruction-analysis program. The tibial AP axis which was defined as the line connecting the middle of the PCL and the medial edge of the patellar tendon attachment was measured relative to the AP axis of distal femur preoperatively and postoperatively, as well as the coronal angle of the tibia and posterior slope. The tibial coronal alignments in navigation, postoperative plain radiograph and CT were compared.

The AP axis of the tibia was in 2.10° internally rotated position relative to the AP axis of the femur preoperatively and 3.54° postoperatively (range, 19.5° internal rotation to 16.8° external rotation). The coronal angle of the tibia was 0.46° varus on plain radiograph, 0.72° varus on CT, 0.37° valgus in navigation (p=0.005). Posterior slope was 2.53° on plain radiograph and 0.67° in navigation (p< 0.001). There was no correlation between postoperative rotational position of the tibia relative to the femur and the difference in the tibial coronal angle between navigation data and CT.

The proposed anteroposterior axis of the tibia centered between 0 to 5 degrees internally rotated position relative to the femur but showed wide range of deviation. The rotation angle of the tibial cutting in navigated TKR did not influence on the postoperative measurement discrepancy between navigation and CT.

The aim of this study was to evaluate passive kinematics of a mobile-bearing, ultracongruent (UC) total knee design compared with a mobile-bearing, posterior stabilised (PS) design intraoperatively using navigation system.

Thirty-four knees of 24 patients which had undergone total knee arthroplasty with UC prosthesis (E-motion^®, Aesculap, Tuttlingen, Germany) for primary osteoarthritis and fifteen knees of 14 patients with PS prosthesis (E-motion^®) were included in this study. Thirty-one female and seven male patients were included and the mean age was 70.4 years. Patients were followed up for 7.26 months (6 to 12 months). Intraoperative kinematics including valgus/varus rotation, internal/external rotation, and anterior/posterior translation was assessed from 10° to 120° of passive flexion before and after total knee replacement using a surgical navigation system (Orthopilot^®, Aesculap). The range of motion (ROM) was measured preoperatively and at the final follow up.

The tibiofemoral alignment in 10° flexion changed from varus 5.85° to valgus 0.38° in UC group and changed from varus 7.45° to valgus 1.08° in PS group (p> 0.05), the magnitude of varus rotation during flexion was 0.01° in UC group and 4.08° in PS group (p< 0.05). PS knee showed the tendency to slight varus alignment during flexion but UC knee showed the tendency toward valgus alignment fter midflexion. The mean internal rotation during flexion was 10.3° in UC group and 13.2° in PS group (p> 0.05). The translation of the femur was 4.99mm posteriorly in UC group and 3.24mm posteriorly in PS group at 120° flexion (p> 0.05). The maximum flexion angle at the final follow up was 123° in UC group and 118° in PS group (p> 0.05). Total knee arthroplasty with high flexion PS prosthesis showed good ROM and satisfactory early clinical results.

UC total knee design showed less varus rotation during flexion, more valgus pattern in higher flexion angle than PS design, similar internal rotation angle and pattern, and similar posterior translation at 120° flexion with PS design.

Ultra-high molecular weight polyethylene (UHMWPE) has been used for the bearing liner or inlay components in total joint replacements such as total hip, knee, and artificial disk since 1960’s. UHMWPE components generate wear debris during articulation, which play a key role in osteolysis, subsequent aseptic loosening, and eventually revision surgery. Efforts to solve the wear problem in UHMWPE and to quantify the amount of wear have driven many studies. But in vivo radiographic penetration depth measurement is the result of both wear and viscoelastic creep. Previous study reported that over 70% of the dimensional changes in UHMWPE acetabular cups were due to creep. Creep deformation was quantified under the static and dynamic compressive pressures (2, 4, 8Mpa) that are clinically relevant for the hip joint loads in normal motions. However, according to the finite element stress analyses in UHMWPE components under the active motions in hip, knee, and artificial disk replacements, very high level of contact pressures locally ranged from under 10MPa up to over 60Mpa. In this study, we quantified the creep of UHMWPE under the several high levels of dynamic compressive pressures and compared the results from the previous results.

For creep tests, UHMWPE rectangular blocks (10mm long, 10mm wide, 8mm thick) were manufactured from molded unirradiated Chirulen^® 1020 sheet (MediTECH, Deutchland). MTS 858 hydraulic test machine was used for conducting the dynamic compressive creep tests under the four different sinusoidal (1Hz) maximum pressures of 10, 20, 40, and 60MPa and minimum pressures of 1, 2, 4, and 6MPa, respectively. All tests were conducted for a total duration of 4×103 minutes at ambient conditions. During the test the displacements of crosshead were stored and the changes in thickness of block specimen devided by the initial thickness were calculated to get the creep strain.

The mean dynamic compressive creep strain increased as the loading time increased and had a linear relationship (R2=0.96) with the logarithmic scale of time for all maximun pressures. Over 90% of total creep strain occurred within the first 103 minutes. The rates of creep strain (slopes of curve fitting in logarithmic scale of time) for each maximum pressure were listed in Table 1 with the rates of creep strain for low maximum pressures from the previous study [3]. The rates of creep strain increased linearly as the maximum pressure increased for both current study (R2=0.96) and previous study (R2=0.99). The slope of linearity for the current study with high levels of contact pressures was a little larger than that for the previous study with low levels of contact pressures. This difference in the slope of linearity between current and previous studies lies in the creep recovery during measurement of specimen thickness by micrometer in the previous study. Neglecting this difference, the results of current study can be extrapolated to anticipate the creep strain of UHMWPE under the dynamic compression for the low levels of contact pressures.

Clinical experience has shown the needs for high flexion. The aim of this study was to evaluate the clinical and radiological results of a fixed bearing high flexion posterior stabilized (PS) total knee arthroplasty (TKA).

Between July 2001 and December 2005, 422 TKAs in 288 patients were performed with high flexion PS prosthesis and 378 knees of 258 patients had been followed up for 2 to 6.5 years (mean: 3 years 11 months). We evaluated range of motion (ROM), Knee rating system of the Hospital for Special Surgery (HSS) and Knee Society (KS) score, and radiological results.

The mean flexion improved from 110.1 degrees to 126.7 degrees at the latest follow-up. 333 knees (88 %) showed more than 120 degrees of flexion, 105 knees (28 %) more than 140 degrees of flexion. The mean KS clinical score improved from 39 to 93 points (p< 0.01) and KS function score, from 40 to 85.4 points (p< 0.01). The mean HSS score improved from 41.2 to 86.3 points (p< 0.01). In 28 knees, radiolucent line of 1–2 mm in width was observed at zone 1 without symptoms. Aseptic loosening in 4 knees, Mid-flexion instability in 2 knees, superficial infection in 3 knees and deep infection in 3 knees were observed.

Total knee arthroplasty with high flexion PS prosthesis showed good ROM and satisfactory early clinical results. Complication rate was similar to those of other series. Close observation and serial radiological evaluation are needed for long term results.

Recently with the introduction of operations using various instrument of total ankle arthroplasty, we are showing quite satisfactory short term results on the treatment of resolved pain of ankle joint. However, there have been reports of high probability of complication from total ankle arthroplasty to other arthroplasty applied to other joints. Therefore in order to make the results of ankle arthroplasty superior, it is necessary to reduce these complications. We try to analyze complications that occur often and come up with the best results.

There were 45 cases of 42 patients of HINTEGRA^® (Newdeal SA, Lyon, France) model from November 2004 to August 2006. Follow up averaged 33.5 months, the average age of patients was 61.1 years, with 14 males and 28 females. We evaluated the complications and analyzed the causes of failures. There was a total 15 cases of complications; 5 cases of medical impingement syndrome, 3 cases of varus malposition, 2 cases of delayed healing of wound, 1 case of peroneal nerve problem, medial malleolar fracture, postoperative deep infection and gouty arthritis pain and Achilles tendinitis.

Our conclusion is that total ankle arthroplasty had more complication rate than other joint arthroplasty, so we need a more meticulous preoperative and perioperative care.

We conducted a randomised prospective study to evaluate the clinical and radiological results of a mobile- and fixed-bearing total knee replacement of similar design in 174 patients who had bilateral simultaneous knee replacement. The mean follow-up was for 5.6 years (5.2 to 6.1).

The total knee score, pain score, functional score and range of movement were not statistically different (p > 0.05) between the two groups. Osteolysis was not seen in any knee in either group. Two knees (1%) in the mobile-bearing group required revision because of infection; none in the fixed-bearing group needed revision. Excellent results can be achieved with both mobile- and fixed-bearing prostheses of similar design at mid-term follow-up. We could demonstrate no significant clinical advantage for a mobile bearing.

We performed a prospective, randomised study to compare the results and rates of complications of primary total knee replacement performed using a quadriceps-sparing technique or a standard arthrotomy in 120 patients who had bilateral total knee replacements carried out under the same anaesthetic. The clinical results, pain scales, surgical and hospital data, post-operative complications and radiological results were compared.

No significant differences were found between the two groups with respect to the blood loss, knee score, function score, pain scale, range of movement or radiological findings. In contrast, the operating time (p = 0.0001) and the tourniquet time (p < 0.0001) were significantly longer in the quadriceps-sparing group, as was the rate of complications (p = 0.0468).

We therefore recommend the use of a standard arthrotomy with the shortest possible skin incision for total knee replacement.