Distal radius fractures are common in South Africa. Accurate, decisive radiographic parameter interpretation is key in appropriate management. Digital radiographic facilities are rare in the public setting and goniometer usage is known to be low, thus, visual estimates are the primary form of radiographic assessment. Previous research associated orthopaedic experience with accuracy of distal radius fracture parameter estimation but, oftentimes, doctors treating orthopaedic patients are not experienced in orthopaedics. A cross-sectional questionnaire including four distal radius fracture radiographs administered to 149 orthopaedic doctors at three Johannesburg teaching hospitals. Participants grouped into ranks of: consultants (n=36), registrars (n=41), medical officers (n=20) and interns (n=52). Participants visually estimated values of distal radius fracture parameters, stated whether they would accept the position of the fractures and stated their percentage of routine usage of goniometers in real practice. The registrar group was most accurate in visually estimating radial height, whilst the interns were least accurate (p=0.0237). The consultant, registrar and medical officer groups were equally accurate in estimating radial inclination whilst the intern group was the least accurate (p<0.0001). The consultant and registrar group were equally accurate at estimating volar tilt, whilst the medical officer and intern groups were least accurate (p<0.0001). The Gwet's AC agreement was 0.1612 (p=0.047) for acceptance of position of the first radiograph, 0.8768 (p<0.0001) for the second, 0.8884 (p<0.0001) for the third and 0.8064 (p<0.0001) for the fourth. All groups showed no difference in goniometer usage, using them largely 0–25% of practice (p=0.1937). The study found that accuracy in visual estimations of distal radius fracture parameters was linked to orthopaedic experience but not linked to routine practice goniometer usage, which was minimal across all groups. Inter-rater agreement on acceptability of fracture position is potentially dependent on severity of deviation from acceptable parameters

Introduction. Intraoperative assessment of coronal alignment is important when performing corrective osteotomies around the knee and ankle, limb lengthening and trauma surgery. The Joint Angle Tool (JAT) provides surgeons with information about the anatomic and mechanical axes intraoperatively based on true anteroposterior radiographs. Aim: Presentation of the JAT, a low-cost goniometer for intraoperative assessment of the lower limb alignment. Materials and Methods. The JAT consists of pre-printed joint orientation angles of the anatomic and mechanical axis including normal variations on a plastic sheet. It is placed on the screen of the image intensifier after obtaining a true anterior-posterior image. The pre-printed joint orientation angles can intraoperatively assist the surgeons in achieving the pre-planned axis correction. Here, its feasibility is demonstrated in four cases. Results. Here, we present the intraoperative use of JAT in four cases:. 77 mm femoral bone transport due to non-union utilizing a bone transport nail,. distal femoral osteotomy correcting coronal and torsional malalignment using a retrograde intramedullary trauma nail,. proximal / high tibial open wedge osteotomy with an intramedullary implant correcting varus malalignment in a hypophosphatemic rickets patient, and. a supramalleolar, closing wedge osteotomy realigning the anatomic axis with a plate and screws. Conclusions. The JAT is a modified goniometer which allows intraoperative assessment of the mechanical and anatomic axis. JAT is applicable throughout the entire surgical procedure irrespective of the method of internal fixation and may provide additional reassurance of correct alignment. The JAT consists of a plastic sheet with printed joint orientation angles and their normal variation. JAT is freely available from . profeedback.dk/JAT/JAT.pdf. for use and modification according to Creative Commons license (CC BY-SA 4.0)

Abstract. Aim. This study aims to Inter and intra observer reliability compare, use of a standard goniometer (SG) to measure intermetacarpal angle (degrees) vs use of a new technique of using a digital vernier calliper (DVC) (mm) to measure the distance between the first and second metacarpal head. Method. Maximal active abduction and extension of both thumbs was measured in 20 healthy volunteers on two occasions at least one week apart by two assessors. Results. The inter and intra-observer agreement was higher & the variance of the data was lower using the DVC with the new technique than the SG for both thumb abduction and extension. Additionally, the correlation between measurement of extension and abduction was higher using the DVC than the SG. Conclusion. Whilst both tools provide acceptable intra and inter-observer agreement, the new technique using a DVC is consistently better and more reliable than a SG in measuring thumb abduction and extension. The study also supports our hypothesis that the thumb rotates around the second metacarpal head with a consistent radius

Intraoperative range of motion (ROM) radiographs are routinely taken during scaphoidectomy and four corner fusion surgery (S4CF) at our institution. It is not known if intraoperative ROM predicts postoperative ROM. We hypothesize that patients with a greater intra-operativeROM would have an improved postoperative ROM at one year, but that this arc would be less than that achieved intra- operatively. We retrospectively reviewed 56 patients that had undergone S4CF at our institution in the past 10 years. Patients less than 18, those who underwent the procedure for reasons other than arthritis, those less than one year from surgery, and those that had since undergone wrist arthrodesis were excluded. Intraoperative ROM was measured from fluoroscopic images taken in flexion and extension at the time of surgery. Patients that met criteria were then invited to take part in a virtual assessment and their ROM was measured using a goniometer. T-tests were used to measure differences between intraoperative and postoperative ROM, Pearson Correlation was used to measure associations, and linear regression was conducted to assess whether intraoperative ROM predicts postoperative ROM. Nineteen patients, two of whom had bilateral surgery, agreed to participate. Mean age was 54 and 14 were male and 5 were male. In the majority, surgical indication was scapholunate advanced collapse; however, two of the participants had scaphoid nonunion advanced collapse. No difference was observed between intraoperative and postoperative flexion. On average there was an increase of seven degrees of extension and 12° arc of motion postoperatively with p values reaching significance Correlation between intr-operative and postoperative ROM did not reach statistical significance for flexion, extension, or arc of motion. There were no statistically significant correlations between intraoperative and postoperative ROM. Intraoperative ROM radiographs are not useful at predicting postoperative ROM. Postoperative extension and arc of motion did increase from that measured intraoperatively

Background. Calipered kinematically aligned (KA) total knee arthroplasty (TKA) restores the in vitro internal-external (I-E) rotation laxities at 0° and 90° of the native knee. Although increasing and decreasing the thickness of the insert in 1 mm increments loosens and tightens the flexion space, there are little data on how this might adversely affect the screw-home mechanism and I-E rotational laxity. The present study determined the differences in the I-E range of rotation and I-E positions at maximum extension and at 90° of flexion that result from the use of insert thicknesses that deviate ± 1mm in thickness from the implanted insert. Methods. 20 patients were treated with a calipered KA and a PCL retaining implant with a 1:1 medial ball-in-socket constraint and a non-constrained lateral flat articular insert surface. Verification checks, that are validated to restore native tibial compartment forces without release of healthy ligaments including the PCL, were used to select the optimal insert thickness. Trial inserts with thicknesses ranging from 10 to 13 mm were 3-D printed with medial goniometric markings that record rotation from 20° external to −20° internal with respect to a sagittal line laser marked on center of the medial condyle of the trial femoral component at maximum extension and 90° of flexion (Figure 1). Results. For all three inserts, the tibial component progressively internally rotated on the femoral component from maximum extension to maximum flexion. From maximum extension to 90° flexion the −21.7° range of internal rotation for the optimal insert thickness was greater than the −16° for the 1mm thinner insert (p < 0.000), and the −13.1° for the 1mm thicker insert (p < 0.000). At maximum extension, the mean insert position of 7° external for the optimal insert thickness was more external than the 4.5° for the 1mm thinner insert (p < 0.000), and the 3.5° for the 1mm thicker insert (p < 0.000) (Figure 2). At 90° the mean −14.7° internal insert position for the optimal insert thickness was more internal than the −11.5° for the 1mm thinner insert (p < 0.000), and the −9.5° for the 1mm thicker insert (p < 0.000) (Figure 3). Discussion and Conclusions. The insert goniometer is an inexpensive, simple, and sensitive instrument that measured the insert position of a medial ball-in-socket PCL retaining implant with a flat lateral insert implanted with calipered KA and showed the I-E rotation matched the pattern of the native knee's screw-home mechanism. Restoring the pre-arthritic native ligament laxities is the target, as the insert goniometer detected a 6° loss of internal rotation and a less external position of the insert at maximum extension and a less internal position at 90° when the healthy ligaments were stretched or loosened by 1mm. For any figures or tables, please contact the authors directly

Introduction:. External rotation (ER) of the shoulder is a commonly used clinical measurement to assess the glenohumeral joint; however, the position in which these measurements are obtained varies between clinicians. The purpose of this study was to compare the following: ER in the upright & supine positions, motion capture & goniometric values of ER, active & passive ER, ER in the right & left shoulders, and ER in male & female subjects. Methods:. Eighteen subjects (mean age 25.4 yrs) with ‘normal’ shoulders (by screening questionnaire) were enrolled in the study and subject to triplicate measurements of active and passive ER of both shoulders with a goniometer and a 12 camera, high speed optical motion analysis system in both the upright and supine positions. ANOVA was used to compare variables and linear regression used to correlate the goniometer & optical motion capture measurements. Results:. On average, shoulder ER in the supine position was 10.0° greater than in the upright position (p < 0.001) using the motion capture data and 5.8° greater using the goniometer (p = 0.025). There was a strong correlation between the goniometer and optical motion capture measurements with an R. 2. value of 0.6573 (p = 2.39E-13); on average, the goniometer readings were 11.0° greater than the corresponding optical measurements. External rotation of the right shoulder was 7.2° greater than the left using the optical measurements (p = 0.02) and 4.4° greater with the goniometer (p = 0.039). In addition, females did have significantly greater external rotation than males using the optical measurements (p < 0.001), averaging 16.7° more external rotation; findings were similar for the goniometric measurements with 18.5° greater average external rotation seen in female subjects (p < 0.001). There was no significant difference between measured active and passive external rotation (p = 0.589). Conclusion:. Significant differences do exist between measured values of external rotation depending on the position of measurement (upright vs supine), hand dominance, and gender. It does not appear that there is a difference between active and passive external rotation. Our recommendations are for the musculoskeletal clinician to be meticulous when documenting the position of measured external rotation, as values vary depending on the position of measurement. One should also be cautious of comparing external rotation of one shoulder to the contralateral side, as well as comparing values between genders, as these measurements appear to be different as well

Although the pre- or intraoperative flexion angle in TKA has been commonly considered as a predictor of the postoperative flexion angle, patients with well flexion intraoperatively cannot necessarily obtain deep flexion angle postoperatively. The reason why inconsistencies remains has been unsolved. The intraoperative compressive force between femoral and tibial components has the advantage of the sequential changes during knee motion. However, the relationship between the compressive force and the postoperative ROM has not yet been clarified. We aimed to evaluate the intraoperative femorotibial compressive force during passive knee motion, and determine the relationship between the compressive force and the postoperative flexion angle. A total of 11 knees in 10 patients who underwent primary cruciate-retaining (CR) TKA (The FINE Total Knee System; Teijin Nakashima Medical Co., Ltd., Okayama, Japan) for osteoarthritis were studied retrospectively, with a mean age of 76 years via a measured resection technique. We developed a customized measurement device mimicking the tibial component with this platform of six load sensors arranged in two rows (medial and lateral) by three tandem sets (anterior, center and posterior): anteromedial (AM), anterolateral (AL); centromedial (CM), centrolateral (CL); and posteromedial (PM), posterolateral compartment (PL) (Fig. 1). At the step of the implant trial, this device was placed on the tibia with compressive force recorded three times, while the knee was subsequently taken from 0° to full flexion manually in 15 seconds with the flexion angle of the knee recorded simultaneously by using an electric goniometer (Fig. 2). Eligibility were evaluated for ROM using a long-armed goniometer preoperatively and at 6 months postoperatively. A p value of < 0.05 was considered significant. The mean compressive force at AM, AL, CM, CL, PM and PL was 0.7, 0.5, 1.3, 1.2, 3.4 and 2.6 kgf, with the peak force of 4.2, 2.5, 4.1, 2.5, 7.3 and 4.7 kgf, respectively. The mean pre- and postoperative extension and flexion angles were −11° and −6°; and 115° and 113°, respectively. There were no significant correlations between the mean force in any region of interest (AM to PL) and the postoperative flexion angle. The peak force in PM showed little correlation with the postoperative flexion angle (r = −0.17, p = 0.54), however, that in PL was strongly negatively correlated with the postoperative flexion (r = −0.86, p < 0.01). The current results suggest the presence of less force on the lateral side in flexion. We speculate that lower compressive force at the lateral side is essential for deep flexion as it has been reported that the lateral structure has more laxity than the medial side during flexion in healthy knees. Measurement between the femoral and tibial compressive force can contribute an achievement of more flexion angle following CR-TKA

Introduction. During its conception, Ilizarov advocated a fine wire tension of between 900N and 1200N for circular frame construction. Wire tension can be achieved via a tensioning device or ‘Russian tensioning’ (a fixed wire lengthening around a bolt). There is limited information on the latter technique. This study aimed to explore the tensions achieved via Russian tensioning and report the impact of a second wire on construct tension. Materials and Methods. A single 160mm stainless-steel ring was constructed, then 1.8mm stainless steel wires secured using a Russian fixation bolt and Russian tensioned with a 2nd bolt. The angle subtended by tensioning using the 2nd bolt was measured using a goniometer. Angles of 45°, 70° and 90° were repeated in triplicates, with wire tension measured using a calibrated tensiometer. A 2nd orthogonal wire was placed on the opposite side and tensioned to the same angle. Tensions of both wires were remeasured and recorded. Statistical comparison using unpaired t-tests was used to compare mean tensions. A value of p<0.05 was considered significant. Results. Russian wire tensioning at all angles was insufficient to achieve the target range of 900–1200N (range 99–110N). The addition of a second orthogonal wire changed frame dynamics such that a 90° angle resulted in both wires achieving adequate tension (mean 1143N, SD 307N). Increases were significant across all tensioning angles (p–<0.002) however only biomechanically relevant for 90°. Conclusions. Russian tensioning is insufficient with a single wire, however the addition of an orthogonal wire increases tension in both wires, which reaches the target range at 90° deflection. This phenomenon is explained by force transmission initially into ring deflection, which is then balanced out by the second wire. Further study of this phenomenon using wire tensioners is warranted, and also the impact of non-orthogonal wire constructs

We sought to validate a method of measuring the range of motion of knees on radiographs as part of a new system of “Virtual Knee Clinics”. The range of motion of 52 knees in 45 patients were first obtained clinically with goniometers and compared to radiographs of these patients' knees in full active flexion and extension. Four methods of plotting the range of motion on the radiographs were compared. The intra-class correlation coefficient (ICC) for inter-rater reliability using the goniometer was very high; ICC=0.90 in extension and 0.85 in flexion. The best ICC for radiographic measurement in extension was 0.86 indicating substantial agreement and best ICC in flexion was 0.95 (method 4). ICC for intra-rater reliability was 0.98 for extension and 0.99 for flexion on radiographic measurements. Measuring range of motion of the knee has never previously been validated in the literature. This study has allowed us to set up a “Virtual Knee Clinic,” combining postal questionnaires and radiographic measurements as a surrogate for knee function. We aim to maintain high quality patient surveillance following knee arthroplasty, reduce our new to follow-up ratios in line with Department of Health guidelines and improve patient satisfaction through reduced travel to hospital outpatients

Aims. Accurate knowledge of the normal shoulder range of movement (ROM) is imperative for evaluating pathology and clinical success. However, in orthopaedic texts, the quoted normal shoulder ROM has significant variation. Furthermore we suspect there is a high incidence of intra and inter observer error during shoulder ROM examination. The aims of our study were thus:. To perform a literature review and record the published values for normal shoulder ROM. Subsequently, to calculate the average of these published values. To perform visual and goniometer measurement of shoulder ROM in 10 volunteers and assess the agreement between the two methods. Methods. A literature search of textbooks, Pub Med and scoring systems was undertaken. Statistical analysis was performed to identify the average value of shoulder movements. Two researchers (specialist trainees in T&O) prospectively assessed 20 shoulders in 10 healthy volunteers. Second observations were made after two weeks. Visual estimation and goniometry assessments were conducted. Bland Altman analysis was performed. Results. The literature review confirmed there to be a wide variation in the normal shoulder ROM. The published average and range values for specific shoulder movements were: forward flexion 165 (117–180), extension 54 (28–80), abduction 171 (117–189), internal rotation 74 (30–110), external rotation 83 (40–117). ROM measurements showed a lack of agreement between visual and goniometer measurements and between time elapsed measurements. Significant intra and inter observer error was also identified. Abduction and external rotation were found to have the greatest disparity. Conclusions. There is stark variation in published figures for normal shoulder ROM. We present the average of published figures. Orthopaedic texts describe different methods for measuring shoulder ROM, which may lead to further confusion and error. Due to the results, we question the validity of including shoulder ROM assessment within accepted scoring systems

BACKGROUND. Telerehabilitation has been shown to both promote effective recovery after shoulder arthroplasty and may improve adherence to treatment. Such systems require demonstration of feasibility, ease of use, efficacy, patient and clinician satisfaction, and overall cost of care, and much of this data has yet to be provided. Few augmented reality rehabilitation approaches have been developed to date. Evidence suggests augmented reality rehabilitation may be equivalent to conventional methods for adherence, improvement of function, and relief of pain seen in these musculoskeletal conditions. We proposed that the development of an augmented reality rehabilitation platform during the pre and postoperative period (including post-shoulder arthroplasty) could be used to track patient activity and range of motion as well as promote recovery. METHODS. A prototype augmented reality platform equipped with a motion sensor system optimised for the upper arm was developed to be used to validate 4 arcs of shoulder motion and complete directed upper arm exercises designed for post-shoulder arthroplasty rehabilitation was built and tested. This system combined augmented reality instructions and motion tracking to follow patients over the course of their therapy, along with a telehealth patient-clinician interface. FINDINGS. The augmented reality platform was tested to validate shoulder range of motion examination similar to that of standard goniometer measurements. Healthy test subjects without shoulder pain or prior shoulder surgery performed the arcs of motion for 5 repetitions as part of a home therapy program. Each motion was measured with angular measurements as a proof of concept with high degree precision (less than 5 degrees). Remote patient-clinician interface testing was also conducted along with a clinician established therapy plan. DISCUSSION. Augmented reality systems that track patients' complex movements, including clinical shoulder range of motion, suggest the promising future of telerehabilitation in arthroplasty, particularly in telemonitoring before and after surgery. As this technology continues to gain acceptance, further studies that evaluate the outcomes of augmented reality rehabilitation for long-term follow-up are needed

Management of a knee with valgus deformities has always been considered a major challenge. Total knee arthroplasty requires not only correction of this deformity but also meticulous soft tissue balancing and achievement of a balanced rectangular gap. Bony deformities such as hypoplastic lateral condyle, tibial bone loss, and malaligned/malpositioned patella also need to be addressed. In addition, external rotation of the tibia and adaptive metaphyseal remodeling offers a challenge in obtaining the correct rotational alignment of the components. Various techniques for soft tissue balancing have been described in the literature and use of different implant options reported. These options include use of cruciate retaining, sacrificing, substituting and constrained implants. Purpose. This presentation describes options to correct a severe valgus deformity (severe being defined as a femorotibial angle of greater than 15 degrees) and their long term results. Methods. 34 women (50 knees) and 19 men (28 knees) aged 39 to 84 (mean 74) years with severe valgus knees underwent primary TKA by a senior surgeon. A valgus knee was defined as one having a preoperative valgus alignment greater than 15 degrees on a standing anteroposterior radiograph. The authors recommend a medial approach to correct the deformity, a minimal medial release and a distal femoral valgus resection of angle of 3 degrees. We recommend a sequential release of the lateral structures starting anteriorly from the attachment of ITB to the Gerdy's tubercle and going all the way back to the posterolaetral corner and capsule. Correctability of the deformity is checked sequentially after each release. After adequate posterolateral release, if the tibial tubercle could be rotated past the mid-coronal plate medially in both flexion and extension, it indicated appropriate soft tissue release and balance. Fine tuning in terms of final piecrusting of the ITB and or popliteus was carried out after using the trial components. Valgus secondary to an extra-articular deformity was treated using the criteria of Wen et al. In our study the majority of severe valgus knees (86%) could be treated by using unconstrained (CR, PS) knee options reserving the constrained knee / rotating hinge options only in cases of posterolateral instability secondary to an inadequate large release or in situations with very lax or incompetent MCL. Results. The average follow up was 10 years (range 8 to 14 years). The average HSS knee scores improved from 48 points preoperatively (range 32 to 68 points) to 91 points (range 78 to 95 points) postoperatively. The average postoperative range of motion measured with a goniometer was 110 degrees (range 80 to 135 degrees) which was a significant improvement over the preoperative levels (average 65 degrees). None of the patients were clinically unstable in the medioloateral or anteroposterior plane at the time of final follow up. The average preoperative valgus tibiofemoral alignment was 19.6 degrees (range 15 degrees to 45 degrees). Postoperatively the average tibio-femoral alignment was 5 degrees (range 2 degrees to 7 degrees) of valgus. No patient in the study was revised. Conclusion. Adequate lateral soft tissue release is the key to successful TKA in valgus knees. The choice of implant depends on the severity of the valgus deformity and the extent of soft tissue release needed to obtain a stable knee with balanced flexion and extension gaps. The most minimal constraint needed to achieve stability and balance was used in this study. In our experience the long term results of TKR on severe valgus deformities using minimal constrained knee have been good

Background. Previous in vivo fluoroscopic studies have documented that subjects having a PS TKA experience a more posterior condylar contact position at full extension, a high incidence of reverse axial rotation and mid flexion instability. More recently, a PS TKA was designed with a Gradually Reducing Radius (Gradius) curved condylar geometry to offer patients greater mid flexion stability while reducing the incidence of reverse axial rotation and maintaining posterior condylar rollback. Therefore, the objective of this study was to assess the in vivo kinematics for subjects implanted with a Gradius curved condylar geometry to determine if these subjects experience an advantage over previously designed TKA. Methods. In vivo kinematics for 30 clinically successful patients all having a Gradius designed PS fixed bearing TKA with a symmetric tibia were assessed using mobile fluoroscopy. All of the subjects were scored to be clinically successful. In vivo kinematics were determined using a 3D-2D registration during three weight-bearing activities: deep-knee-bend (DKB), gait, and ramp down (RD). Flexion measurements were recorded using a digital goniometer while ground reaction forces were collected using a force plate as well. The subjects then assessed for range of motion, condyle translation and axial rotation and ground reaction forces. Results. During a DKB, subjects implanted a Gradius designed, PS fixed bearing TKA design exhibited an average of 3.35 mm of posterior femoral rollback of the lateral condyle and 2.73 mm of the medial condyle with an average axial rotation of 4.90° in the first 90° of flexion. The average max flexion was 111.4°. From full extension to maximum flexion, the average axial rotation was 4.73°, while the subjects experienced 5.34 and 1.97 mm on the lateral and medial condyle rollback, respectively. During mid flexion from 30 to 60 degrees of flexion, the subjects experienced 1.34° of axial rotation, −1.13 and −0.11 mm of lateral and medial condyle motion. Conclusions. Subjects in this study did experience good weight-bearing flexion and magnitudes of axial rotation and posterior femoral rollback similar to previous PS TKA designs. During mid flexion, subjects in this study did experience less mid flexion paradoxical sliding than other PS TKA, leading to greater mid flexion stability for the patients

Range of motion (ROM) is a well recognised outcome measure following total knee arthroplasty (TKA). Reduced knee flexion can lead to poor outcome after TKA and therefore identification at an early stage is important as it may provide a window for intervention with targeted physiotherapy, closer follow-up and in resistant cases possible manipulation or arthrolysis. ROM combines both flexion and extension and in contrast to flexion, fewer studies have recognised the importance of a lack of full extension or fixed flexion deformity (FFD) following TKA. A residual FFD can increase energy cost, decrease velocity during ambulation and result in pain with knee scores more likely to be diminished than if knee extension was normal. Recognition and early detection of FFD is therefore important. Methods of assessment include by visual estimation or goniometric measurement of knee flexion angle. While goniometers are inexpensive, easy to use and provide more accurate than visual estimates of angles, they have been shown to exhibit poor inter-observer reliability. Therefore they may not be sensitive enough to consistently identify FFD and therefore distinguish between grading systems based on absolute angular limits. The aim of this study was to investigate the accuracy of standard clinical ROM measurement techniques following TKA and determine their reliability for recognising FFD. Ethical approval was obtained for this study. Thirty patients who were six weeks following TKA had their knee ROM measured. An infrared (IR) tracking system (±1°accuracy) that had been validated against an electro-goniometer was used to give a “true” measurement of the lower limb sagittal alignment with the knee fully extended and maximally flexed while the patient was supine. The patients were also assessed independently by experienced arthroplasty practitioners using a standardised goniometric measurement technique. For goniometric clinically-measured flexion (Clin. flex). and extension (Clin. ext. ) linear models were generated using IR-measured flexion and extension (IR. flex. and IR. ext. ), BMI and gender as covariables. Data for extension were categorised in none, moderate and severe postoperative FFD as per Ritter et al. 2007 and agreement in classification between the two methods was assessed using the Kappa statistic. For the linear models for Clin. flex. and Clin. ext. neither BMI nor gender were significant variables. Therefore the final models were:. Clin. flex. = 0.54 + 0.66∗IR. flex. (r. 2. adj. = 0.521). Clin. ext. = 0.23 + 0.50∗IR. ext. (r. 2. adj. = 0.247). The model for Clin. flex. showed that the IR and clinical measurements coincided at approximately 90° so that for every 10° increase in flexion above 90° clinical measurement only increased by 7° but for every 10° decrease in flexion below 90° clinical measurement only decreased by 7°. The model for Clin. ext. showed that the IR and clinical measurements coincided at approximately 0° so that for every 10° increase in FFD angle, clinical measurement only increased by 5° but if the knee went into hyperextension this would be underestimated by the clinical measure. In identifying FFD there was moderate agreement between the two measurements (κ = 0.44). Clinically nine patients were assessed as having FFD but the IR measurements showed 18 patients having FFD, of which nine patients were not identified clinically. When assessing knee ROM following joint arthroplasty manual goniometric measurements provided a poor estimate of the range when compared to the “true” angle as measured with a validated IR measurement tool. When the knee was held in maximum flexion there was a tendency to both underestimate and overestimate the true angle. However when the knee was held in extension there was a tendency to underestimate which we believe is important as it would underreport both the frequency and magnitude of FFD. In our study, 18 patients had a moderate FFD as identified by the IR system, only half of which were identified by goniometer measurement alone. Studies of comparisons of both visual and manual goniometry measurements of the knee in maximum flexion with lateral radiographs have shown most errors involved an underestimate of true flexion. It has been concluded that it was safer to underestimate knee flexion angle as it would result in higher pick up rate of cases being performing less well. In contrast however, underestimation while in extension is less desirable as it fails to pick-up FFD which may have benefited from intervention had they been identified. It is known that residual FFD can increase energy cost and decrease velocity during ambulation with pain and functional knee scores more likely to be reduced. Recognition and early detection is therefore important. With the use of more accurate systems to identify and measure FFD, such as the one used for this study may in turn allow more timely treatment and therefore hopefully improved outcomes

Sagittal stability of the knee is believed to be of significant importance following total knee arthroplasty. We examine four different knee designs at a minimum of twenty-four months postoperatively. Sagittal stability was measured at four degrees of flexion: 0°; 30°; 60°; and 90°, to examine the effect of design on mid-flexion stability. The knee designs included were: the rotating platform LCS design (DePuy); the cruciate sparing Triathlon system (Stryker); SAIPH system (Matortho, UK); and the medial rotating knee design, MRK (Matortho, UK). Following ethical approval, 64 cases were enrolled into the study, 22 male and 42 female. Inclusion criteria included: a minimum of 18 months from surgery; ability to flex beyond 90 degrees; and have no postoperative complications. 18 LCS, 18 MRK, 14 SAIPH and 14 Triathlon knee designs were analysed. Sagittal stability was measured using the KT1000 device. Active range of movement was measured using a hand held goniometer and recorded as was Oxford knee score, WOMAC knee score, SF12 and Kujala patellofemoral knee score. Mean follow-up was 33.7 months postoperative, with a mean age of 72 years. Mean weight was 82.7kgs and height 164cms. There was no significant difference in preoperative demographics between the groups. Mean active post-operative range of motion of the knee was from 2–113° with no significant difference between groups. Sagittal stability was similar in all four groups in full extension; however the MRK and SAIPH designs showed improved stability in the mid-range of flexion (30–90°). Patient satisfaction also showed a similar trend with MRK achieving better patient reported functional outcomes and satisfaction than that of the SAIPH, LCS and Triathlon systems. All four knee designs demonstrated good post-operative range of movement with comparative improvement of patient scores to other reported studies. The MRK and SAIPH knee design showed an improved mid-flexion sagittal stability with better patient reported satisfaction and functional scores

Postoperative functional outcomes and patients’ satisfaction after total knee arthroplasty are associated with postoperative range of motion. Severe deformities require surgical correction such as soft tissue release and appropriate bone resection. The goal of surgery is to correct the contracture and bring the knee to good range of motion. Using gap-balancing technique is one of the major techniques to obtain good range of motion. Although the gaps are well balanced, the thickness of tibial insert would affect the range of motion. In this study, we analyzed the difference between intraoperative extension joint gap and the thickness of implanted insert (DJI). The objective of this study was to investigate whether DJI affected the postoperative extension of the knee. A total of 155 knees were analyzed retrospectively. Subject included 27 males and 128 females with an average of 72.7 ± 7.0 years. The mean preoperative knee flexion angle was 136.1 ± 20.0°and the mean preoperative knee extension deficit was 4.0 ± 6.1°. All the patients had a diagnosis of varus-type osteoarthritis, identical prostheses (Stryker NRG posterior-stabilized type) implanted with a modified gap-balancing technique and no postoperative complications which may have affected the range of motion. Range of motion was measured using a goniometer before surgery and 12 months after surgery. Joint gap between femoral component and proximal tibia in full extension was measured by a tensor/ balancer device which added joint gap an expansion force by 30 inch pounds intra-operatively. Although we empirically regarded the appropriate DJI was 5 mm for this prosthesis, we determined the thickness of the tibial inserts considering preoperative range of motion. Thinner inserts compared with the joint gap was implanted for knees with flexion contracture and thicker inserts was implanted for knees with hyperextension. In this study, to determine the relationship of DJI and flexion contracture, the correlation coefficient between DJI and extension deficit was calculated. The diagram of DJI and postoperative extension angle is shown in Figure 1. The correlation coefficient between DJI and postoperative extension deficit was 0.24, which showed that DJI slightly affected the postoperative extension of the knee. Flexion contracture cannot be corrected by simply adjusting DJI

INTRODUCTION. The extension and flexion gaps are affected by different factors in total knee arthroplasty (TKA). Flexion but not extension gap measurements are influenced by posterior cruciate ligament (PCL) preservation or resection and patella reduction or eversion and thigh weight. If the flexion gap is measured with the thigh placed on the tibia, the measurement results must include the thigh weight; nevertheless, there is no detailed report regarding the thigh weight influence on the flexion gap. In this study, we investigated how thigh weight affected flexion gap measurement. METHODS. Four knees of whole-body fresh-frozen cadavers (Mongolian race) were investigated. The femur and tibia were dissected with a standard measured resection technique. After the femoral component was set, the flexion gap was measured with a knee balancer. The distraction force of 20, 30, and 40 pounds were loaded at the joint level. For each measurement, the influences of the patella reduced or everted (PR or PE) and the PCL preserved or resected (CR or PS) were estimated. The flexion gap was measured five times in four different categories (CR/PR, CR/PE, PS/PR, PS/PE) and the thigh weight was reduced by weights (0, 0.5, 1.0, 2.0, 3.0 kg) using a string and pulley system. During measurement, the femur was just placed on the tibia, and the knee flexion angle was maintained at 90 degrees with a goniometer. After all measurements, the lower limbs were resected, and the thighs were weighed with a scale. Steel-Dwasstest (non-parametric multiple comparison test) were performed for statistical analysis, and p < 0.05 was considered significant. RESULTS. Flexion gap measurement results show over 10 mm difference between the maximum gap (PS/PE, 40 lbs, 3 kg weight reduction) and the minimum gap (CR/PR, 20 lbs distraction, no weight reduction) in this study. When a 0.5 kg weight reduction was applied, there were no significant flexion gap increases compared to no weight reduction situation in almost all categories except for “CR/PR and 40 lbs distraction”. According to the increase of the weight reduction, the flexion gap became larger in all categories. When a 3 kg weight reduction was applied, there were significant flexion gap increases compared to no weight reduction situation in all categories (Table 1-3). The mean thigh weight was 2.3 kg (2.0–2.6 kg). DISCUSSION. The flexion gap is usually measured with the thigh placed on the tibia in TKA, and the measurement results are considered to include the influence of the thigh weight even though this has not been discussed in the literature. From our results, the influence of the thigh weight reduction on the flexion gap was different according to heaviness of the reduction weight. When the reduction weight was over the thigh weight, flexion gap increase relative to the flexion gap without weight reduction was significant in all categories nevertheless different situations of the PCL, patella position, and joint distraction forces. To estimate adequate flexion gap and avoid post-operative flexion gap looseness, the thigh weight should be reduced when the flexion gap is measured

To investigate the effectiveness of avulsion fracture of tibial insertion of posterior cruciate ligament using the safe postero-medial approach through analyzing the clinical and radiographic outcomes. We treated 14 cases of acute PCL tibial avulsion fracture with “safe postero-medial approach”. The PCL and avulsion bony fragment was fixed with 1 cannuated screw and washer. The patients were assessed clinically and radiographically at 3 months, 6 months, and 12 months. Clinical examination for each visit included assessment of the knee range of motion, using goniometer and the posterior drawer test. The patients were evaluated according to the Lysholm and Tegner rating scales. Patients were followed-up for 12 to 16 months. X-ray showed that satisfactory reducdtion and bony healing was achieved in all cases. There was no neurovascular complication. All patients had negative posterior drawer tests. Excellent outcomes were reported by all patients with the Lysholm score system. And there was no signicant difference between the Tegner scores before injury and last follow-up. Surgical treatment of acute tibial avulsion fracture of the PCL with this approach can restore the stability and fuction of the joint safely in most patients without neurovascular complication. Therefore “safe postero-medial approach” may be suitable for the treatment of isolated tibial avulsion fracture of the PCL

INTRODUCTION. Wettability of bearing couples has always been related to the tribological performance of implants, and it is understood to affect lubrication of surfaces. So far researchers fail to understand the real mechanisms governing the lubrication process of prostheses. Different models attempt to explain the phenomena, but more research is needed. To add more difficulties, some classical measuring techniques have provided inaccurate values of surface properties. For instance, wettability may seem a priori a simple technique capable of providing easy-to-read cost-effective information. However, ignoring surface preparation may lead to wrong values of wettability and mis-understanding of the results. OBJECTIVES. The dependence of wettability of commercial bearing materials used in arthroplasty has been studied as a function of the cleaning procedure, showing the variability of the results, and providing a series of guidelines to understand and perform wettability measurements. EXPERIMENTAL METHODS. Three different materials were tested: BIOLOX®forte and BIOLOX®delta (CeramTec GmbH, Plochingen), and Cobalt Chrome Molybdenum alloy (CoCrMo; ISO 5832-12). All samples were polished to comparable mirror finish. For wettability assessment, water sessile drop contact angle tests both in static and dynamic mode in a goniometer (KRÜSS model DSA25) with automatic drop dozer were performed, and the images analysed with a proprietary computer software (KRÜSS DSA4 version 1.0). The samples were cleaned using different methods found in the literature (organic solvents, sonication, wipers) and compared with the industrial procedure CeramTec uses before packaging and sterilizing (“Production Cleaning”). RESULTS AND DISCUSSION. Wettability assessment is very sensible to contamination. High variability of the contact angles was found among the three materials investigated, with values ranging from 25 to 90°. By studying the difference between advancing and receding angles (hysteresis) when performing dynamic contact angle tests, the best cleaning method was achieved by the one yielding the lowest hysteresis. Production Cleaning was the best cleaning method, meaning it is capable of removing most sources of heterogeneities (i.e. surface contamination), yielding values of static contact angle of 28.7 ± 3.9° for BIOLOX®forte, 32.0 ± 4.0° for BIOLOX®delta, and 49.8 ± 7.4° for CoCrMo alloy. Cleaning with ethanol in sonication was not sufficient to remove adsorbed contaminants in the surface and left hydrophobic traces. Also usage of wipers in combination with organic solvents is discouraged as a single cleaning method because they are incapable of removing well-adsorbed contaminants. CONCLUSION. Wettability measurements are easy to perform but difficult to interpret, and the effect of contamination must be respected. The results of this work demonstrate a major influence of the cleaning process on the results. When cleaned properly, BIOLOX® ceramics exhibit a more hydrophilic response than CoCrMo. ACKNOWLEDGMENTS. The authors would like to acknowledge the European Commission funding under the 7th Framework Program (Marie Curie Initial Training Networks; grant number: 289958, Bioceramics for bone repair)

Introduction. A total knee replacement is a proven cost-effective treatment for end-stage osteoarthritis, with a positive effect on pain and function. However, only 80% of the patients are satisfied after surgery. It is known that high preoperative expectations and residual postoperative pain are important determinants of satisfaction, but also malalignment, poor function and disturbed kinematics can be a cause. The purpose of this study was to investigate the correlation between the preoperative function and the postoperative patient reported outcomes PROMs) as well as the influence of the postoperative functional rehabilitation on the PROMs. Methods. 57 patients (mean 62,9j ± 10,6j), who suffer from knee osteoarthritis and who were scheduled for a total knee replacement at our centre, participated in this study. The range of motion of the knee, the muscle strength of the M. Quadriceps and the M. Hamstrings and the functional parameters (‘stair climbing test’ (SCT), ‘Sit to stand’ (STS) and ‘6 minutes walking test’ (6MWT)) were measured the night before surgery, ±6 months and ±1 year after surgery. This happened respectively with the use of a goniometer, HHD 2, stopwatch and the ‘DynaPort Hybrid’. Correlations between pre- and postoperative values were investigated. Secondly, a prediction was made about the influence of the preoperative parameters on on the subjective questionnaires (KOOS, OXFORD and KSS) as well as a linear and logistic regression. Results. 6 Months after surgery, an improvement of all parameters for ROM, muscle strength and functional status was found. With a significant difference for the active and passive ROM toward knee flexion (p=0.007;p=0.008), asymmetry in active and passive ROM toward flexion between the healthy leg and the leg with the TKA (p=0.001;p=0.001), Quadriceps- and Hamstrings strength (p=0.001;p<0.001), time of the STS test (p=0.012), time sit-stand (p=0.002), time stand-sit (p=0.001;p<0.001), all parameters for the 6MWT and the time of the SCT (p=0.001). Regarding the prediction model, the 6month PROMs can be predicted by some parameters for the 6MWT (distance (p=0.001), gait steps (p=0.002) and step time TKA (p=0.007)). These parameters are predictors for the score on the subscales ‘symptoms’ and ‘pain’ of the KOOS questionnaire. 1 Year after surgery, there is an improvement of all parameters, except for the active and passive ROM toward knee extension. However, these differences are not significant. The 1 year PROMs can only be predicted by the muscle strength (Quadriceps- and Hamstrings strength (p=0.026; p=0.039) and the asymmetry in Quadriceps strength between the healthy leg and the leg with the TKA (p=0.031)). The score on the subscale ‘pain’ can be predicted based on the parameters mentioned above. Conclusion. Patient satisfaction after TKA is a multivariate model. Regarding the functional outcome, we could find that there is a correlation between the muscle force, walking distance and the PROMs. More research is currently being done to create a better prediction model and investigate the correlations more thoroughly