The efficacy and safety of patient-specific instrumentation in primary total knee replacement: a systematic review and meta-analysis.

INTRODUCTION: Patient-specific instrumentation (PSI) for primary total knee arthroplasty (TKA) surgery has been shown to increase accuracy of component positioning. However, it is unclear whether this also translates to actual benefits for patients in terms of better outcomes (efficacy) or less complications such as revisions (safety). We therefore systematically reviewed the literature to determine the efficacy and safety of PSI in primary TKA. METHODS: Randomized controlled trials comparing PSI to non-PSI in primary TKA were included. A random effects model was used with meta-regression in case of heterogeneity. RESULTS: Forty-three studies were included with a total of 1816 TKA in the PSI group and 1887 TKA in the control group. There were no clinically relevant differences between the PSI-group and non-PSI group regarding all outcomes. There was considerable heterogeneity: meta-regression analyses showed that the year the study was published was an important effect modifier. Early publications tended to show a positive effect for PSI compared to non-PSI TKA, whereas later studies found the opposite. CONCLUSION: Based on evidence of moderate certainty, our study suggested that there were no clinically relevant differences in efficacy and safety between patients treated with PSI TKA and patients treated with non-PSI TKA.

Translation and Validation of 'Foot Health Status Questionnaire' in Dutch.

The aim of our study was to develop a Dutch version of the Foot Health Status Questionnaire (FHSQ-NL) and evaluate its measurement properties according to the COSMIN definition (COnsensus-based Standards for the selection of health Measurement INstruments). After translation of the FSHQ, a group of 119 randomly selected patient who visited the outpatient clinic for conditions affecting the foot and ankle were asked to participate, of which103 patients were included in the analysis. The FHSQ-NL, a validated Dutch FAOS and a visual analogue scale (VAS) for pain and function were used in this study as outcomes measures. Reliability was assessed by calculating intraclass correlation coefficient (ICC), internal consistency by Cronbach's alpha, and the smallest detectable change (SDC). Construct validity was evaluated by use of a priori hypotheses concerning Spearman's correlation coefficient between FHSQ subscales and FAOS and VAS. All domains of the FHSQ-NL, besides 'General health,' indicated good internal consistency with a Cronbach's alpha ranging from 0.61 to 0.91. Test-retest reliability of all FHSQ domains was poor with an ICC ranging from 0.47 to 0.77. At individual level, the SDC ranged from 35.1 to 60.6 and at a group level (n = 50) from 5.0 to 8.6. Construct validity was supported by confirmation of 75% of all a priori hypotheses. The FHSQ-NL has good internal consistency and smallest detectable change (SDC) at group level. However, reliability and SDC on individual level show suboptimal results. Therefore, the questionnaire is more suitable for evaluating foot complaints at group level instead of individual level.

Total knee arthroplasty improves gait adaptability in osteoarthritis patients; a pilot study.

Background: Gait adaptability is of utmost importance for keeping balance during gait in patients with knee osteoarthritis, also after total knee arthroplasty (TKA). The aims of this explorative study are: (1) assess the effect of age, knee osteoarthritis and TKA on gait adaptability; (2) assess changes in gait adaptability pre-to post-TKA and (3) their relation to functional outcomes. Methods: Gait adaptability was measured using a Target Stepping Test (TST) in knee osteoarthritis patients before (preTKA) and 12 months after TKA (postTKA) and compared to asymptomatic old (AsOld) and young adults (AsYng). TST imposed an asymmetrical gait pattern with projected stepping targets at high walking speed. Gait adaptability was determined through stepping accuracy on the targets. The Oxford Knee Score (OKS) and Timed-Up-and-Go test (TUG) measured patients' physical function. Results: 12 preTKA, 8 postTKA, 18 AsYng, 21 AsOld were tested. Age showed no effect on TST-stepping accuracy. PreTKA showed worse TST-stepping accuracy compared to AsYng and AsOld (7.7; 6.2 cm difference). PostTKA showed an improvement of 52% in TST-stepping accuracy compared to preTKA (3.2 cm).Higher stepping accuracy preTKA predicted higher stepping accuracy post-TKA. In addition, low preTKA stepping accuracy predicted more improvement postTKA. Pre-to post-TKA improvement of stepping accuracy was related to improvement on the TUG (Beta = 0.17, p = 0.024), but not to OKS. Conclusions: Gait adaptability is improved following TKA in knee osteoarthritis patients and no longer significantly worse than asymptomatic adults. The relation of gait adaptability to function is shown by its relation to the TUG and shows to have predictive value pre-to post-TKA.

Limited knee extension during gait after total knee arthroplasty is related to a low Oxford Knee Score.

BACKGROUND: After total knee replacement (TKR) some patients report low self-perceived function, which is clinically measured using patient reported outcome measures (PROMs). However, PROMs, e.g. the Oxford Knee Score (OKS), inherently lack objective parameters of knee function. Biomechanical gait analysis is an objective and reliable measurement to quantitatively assess joint function. Therefore, the aim of this study was to explore the relationship between biomechanical gait parameters and the OKS. METHODS: Gait analyses were recorded in 37 patients at least one year after primary TKR and in 24 healthy controls. Parameters from this analysis were calculated for hip, knee and ankle joint angles and joint moments in the sagittal and frontal plane including initial contact, early, late stance and swing. For the patients these parameters were expressed as its difference to control values at matched walking speed. Linear regression analyses were performed between the parameters from gait analysis and the OKS, with speed as covariate. RESULTS: The difference in knee extension angle at initial contact and late stance between patients and controls was significantly related to the OKS. Per one degree knee extension difference increase, the OKS reduced with 1.0 to 1.6 points. Overall, patients extended their knee less than controls. Neither ankle and hip gait parameters, nor joint moments showed a relation with OKS. CONCLUSIONS: All patients with a submaximal score on the OKS showed limited knee extension during gait, even without a mechanical constraint in knee extension. This could be related to motor control limitations in this patient group.

Matching walking speed of controls affects identification of gait deviations in patients with a total knee replacement.

BACKGROUND: The assessment of functional recovery of patients after a total knee replacement includes the quantification of gait deviations. Comparisons to comfortable gait of healthy controls may incorrectly suggest biomechanical gait deviations, since the usually lower walking speed of patients already causes biomechanical differences. Moreover, taking peak values as parameter might not be sensitive to actual differences. Therefore, this study investigates the effect of matching walking speed and full-waveform versus discrete analyses. METHODS: Gait biomechanics of 25 knee replacement patients were compared to 22 controls in two ways: uncorrected and corrected for walking speed employing principal component analyses, to reconstruct control gait biomechanics at walking speeds matched to the patients. Ankle, knee and hip kinematics and kinetics were compared over the full gait cycle using statistical parametric mapping against using peak values. FINDINGS: All joint kinematics and kinetics gait data were impacted by applying walking speed correction, especially the kinetics of the knee. The lower control walking speeds used for reference generally reduced the magnitude of differences between patient and control gait, however some were enlarged. Full-waveform analysis identified greater deviating gait cycle regions beyond the peaks, but did not make peak value analyses redundant. INTERPRETATION: Matching walking speed of controls affects identification of gait deviations in patients with a total knee replacement, reducing deviations confounded by walking speed and revealing hidden gait deviations related to possible compensations. Full-waveform analysis should be used along peak values for a comprehensive quantification of differences in gait biomechanics.

No differences in cost-effectiveness and short-term functional outcomes between cemented and uncemented total knee arthroplasty.

BACKGROUND: There is an ongoing debate regarding optimal fixation of total knee arthroplasty (TKA), however cost has not been addressed as profoundly. Therefore, the current study primarily aimed to compare costs and cost-effectiveness 1 year after cemented or uncemented TKA. A secondary objective was to compare short-term functional outcomes between both groups. METHODS: A posthoc prospective observational multicenter cohort study of 60 cemented and 50 uncemented Low Contact Stress (LCS) knee systems. Outcome was evaluated using the EuroQol5D-3 L (EQ5D) index, in order to calculate quality adjusted life years (QALYs). Total costs were calculated considering direct costs within the hospital setting (inpatient cost) as well as direct and indirect costs outside the hospital. Cost-effectiveness (total costs per QALY), Oxford Knee Score (OKS) and Numeric Rating Scale (NRS) were compared between cemented and uncemented cases at 1 year after surgery. HealthBASKET project, a micro-costing approach, represents the Dutch costs and situation and was used to calculate hospital stay. (In) direct costs outside the healthcare (medical cost and productivity cost) were determined using two validated questionnaires. RESULTS: Median costs per QALY were similar between cemented and uncemented TKA patients (€16,269 and €17,727 respectively; p = 0.50). Median OKS (44 and 42; p = 0.79), EQ5D (0.88 and 0.90; p = 0.82) and NRS for pain (1.0 and 1.0; p = 0.48) and satisfaction (9.0 and 9.0; p = 0.15) were also comparable between both groups. CONCLUSION: For this type of knee implant (LCS), inpatient hospital costs and costs after hospitalization were comparable between groups.

Measurement properties of the most commonly used Foot- and Ankle-Specific Questionnaires: the FFI, FAOS and FAAM. A systematic review.

PURPOSE: In the foot and ankle literature, a wide range of patient-reported outcome measures (PROMs) is used, however, consensus as to which PROMs are preferred is lacking. Selection of a PROM is among other reasons, often based on measurement properties without considering the methodological quality of the studies that evaluate these measurement properties. The aim of current study was first to identify the most frequently used foot and ankle-specific PROMs in recent orthopaedic foot and ankle literature, and second to conduct a systematic review to synthesize and critically appraise the measurement properties of these PROMS. METHODS: Six PubMed indexed journals focussing on foot and ankle research were screened to identify most commonly used foot and ankle-specific PROMs over a 2 year period (2015-2016). Subsequently, a systematic literature search was performed in PubMed, EMBASE, SPORTDiscus and Scopus to identify relevant studies on their measurement properties. Methodological quality assessment was performed using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist, criteria for good measurement properties were applied, and a level of evidence was determined for the measurement properties of each domain of the questionnaires. RESULTS: The three most frequently reported PROMs were the Foot Function Index (FFI), the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Activity Measure (FAAM). Among 2046 unique citations, 50 studies were included evaluating these PROMs. Evidence to support the measurement properties of the FFI was mainly lacking due to poor methodological quality. More evidence was available for the measurement properties of the FAOS and the FAAM, but overall evidence supporting all measurement properties is not yet sufficient. CONCLUSION: The best available evidence retrieved in this review showed that the FAOS and the FAAM are promising outcome measures for evaluation of patients with foot and ankle conditions, but their shortcomings should be taken into account when interpreting results in clinical setting or trials. LEVEL OF EVIDENCE: I.

Preoperative strength training for elderly patients awaiting total knee arthroplasty.

Objective. To investigate the feasibility and effects of additional preoperative high intensity strength training for patients awaiting total knee arthroplasty (TKA). Design. Clinical controlled trial. Patients. Twenty-two patients awaiting TKA. Methods. Patients were allocated to a standard training group or a group receiving standard training with additional progressive strength training for 6 weeks. Isometric knee extensor strength, voluntary activation, chair stand, 6-minute walk test (6MWT), and stair climbing were assessed before and after 6 weeks of training and 6 and 12 weeks after TKA. Results. For 3 of the 11 patients in the intensive strength group, training load had to be adjusted because of pain. For both groups combined, improvements in chair stand and 6MWT were observed before surgery, but intensive strength training was not more effective than standard training. Voluntary activation did not change before and after surgery, and postoperative recovery was not different between groups (P > 0.05). Knee extensor strength of the affected leg before surgery was significantly associated with 6-minute walk (r = 0.50) and the stair climb (r - = 0.58, P < 0.05). Conclusion. Intensive strength training was feasible for the majority of patients, but there were no indications that it is more effective than standard training to increase preoperative physical performance. This trial was registered with NTR2278.

Treatment of malunited fractures of the ankle: A long-term follow-up of reconstructive surgery.

In this retrospective study, using the prospectively collected database of the AO-Documentation Centre, we analysed the outcome of 57 malunited fractures of the ankle treated by reconstructive osteotomy. In all cases the position of the malunited fibula had been corrected, in several cases it was combined with other osteotomies and the fixation of any non-united fragments. Patients were seen on a regular basis, with a minimum follow-up of ten years. The aim of the study was to establish whether reconstruction improves ankle function and prevents the progression of arthritic changes. Good or excellent results were obtained in 85% (41) of patients indicating that reconstructive surgery is effective in most and that the beneficial effects can last for up to 27 years after the procedure. Minor post-traumatic arthritis is not a contraindication but rather an indication for reconstructive surgery. We also found that prolonged time to reconstruction is associated negatively with outcome.

Stimulation of bone cell differentiation by low-intensity ultrasound--a histomorphometric in vitro study.

Several investigations have established a stimulatory effect of low-intensity ultrasound treatment on osteogenesis and fracture healing. The objective of this study was to examine whether the stimulatory effect of low-intensity ultrasound results in increased bone cell activity and/or proliferation. Twenty-four paired triplets of metatarsal bone rudiments of twelve 17-days-old fetal mice were dissected and divided into two groups. One group of bone rudiments was treated with pulsating low-intensity ultrasound (30 mW/cm(2); 1.5 MHz) for 20 min/day for a period of 3 or 6 days. The other group served as controls. After culture, the metatarsal bone rudiments were prepared for computer aided light microscopy. The following histomorphometric parameters were determined: length, width and volume of the calcified cartilage and of the bone collar, and cell number. GLM analysis demonstrated that bone collar volume and calcified cartilage percentage were significantly higher in the ultrasound-stimulated rudiments compared to untreated controls. Further, the calcified cartilage volume bordering the hypertrophic zone was significantly higher than in the center of the bone rudiment. Ultrasound treatment did not change the number of the cells. These results suggest that the stimulatory effect of low-intensity ultrasound on endochondral ossification is likely due to stimulation of bone cell differentiation and calcified matrix production, but not to changed cell proliferation.

Operative treatment of mid-shaft clavicular non-union.

Between 1974 and 1999, we treated operatively 28 patients with a symptomatic mid-shaft clavicular non-union using AO osteosynthesis, including bone grafting. Nine patients had a wave-plate osteosynthesis and 19 a standard AO/ASIF osteosynthesis. The mean follow-up was 10 (2-25) years. All but one non-union showed full bony consolidation. Pre-operatively, brachialgia was present in 12 patients. Of these patients, six were treated using standard osteosynthesis technique and six by wave-plate osteosynthesis. Post-operatively, patients treated by wave-plate osteosynthesis had no brachialgia and also had a higher Constant score than those patients treated using standard AO/ASIF techniques.

[Effects of low-intensity ultrasound on bone. Perspectives for dentistry?]. / Effecten van lage-intensiteit ultrageluid op bot. Perspectieven voor de tandheelkunde?

Low-intensity ultrasound is frequently used for non-invasive diagnostic purposes. However, low intensity ultrasound can also be used as a therapeutical agent. It has been concluded from animal experiments that it significantly stimulates the growth of bone. In clinical trials an accelerated healing of fracture has been found. Future research has to define the role in dentistry and the final therapeutical value of low intensity ultrasound.

Low-intensity pulsed ultrasound in the treatment of nonunions.

BACKGROUND: Low-intensity ultrasound has demonstrated an acceleration of bone healing and more profound callus formation in animal and human clinical experiments. In this study, the effect of pulsed, low-intensity ultrasound was determined in established nonunion cases. METHODS: The enrolled cases were reviewed for the time from their last surgical procedure and evidence of no healing or progression of healing during the 3 or more months before the start of low-intensity ultrasound therapy to determine whether the cases were established nonunions. Twenty-nine cases, located in the tibia, femur, radius/ulna, scaphoid, humerus, metatarsal, and clavicle, met the criteria for established nonunions. On average, the postfracture period before the start of ultrasound treatment was 61 weeks. Initial fracture treatment was conservative in 8 cases and operative in 21 cases. Additional treatments including bone grafting, reosteosynthesis, and other surgical procedures were performed an average of 52 weeks before the start of ultrasound treatment. Daily, 20-minute applications of low-intensity ultrasound at the site of the nonunion were performed by the patients at home. RESULTS: Twenty-five of the 29 nonunion cases (86%) healed in an average treatment time of 22 weeks (median, 17 weeks). Stratification of the healed and failed outcome for age, gender, concomitant disease, bone location, fracture age, prior last surgery interval, nonunion type, smoking habits, and fixation before and during treatment showed a significant difference only in the smoking habit strata. CONCLUSION: Noninvasive ultrasound therapy can be useful in the treatment of challenging, established nonunions.

Low-intensity ultrasound stimulates endochondral ossification in vitro.

Animal and clinical studies have shown an acceleration of bone healing by the application of low-intensity ultrasound. The objective of this study was to examine in vitro the influence of low-intensity ultrasound on endochondral ossification of 17-day-old fetal mouse metatarsal rudiments. Forty-six triplets of paired metatarsal rudiments were resected 'en block' and cultured for 7 days with and without low-intensity ultrasound stimulation (30 mw/cm2). At days 1, 3, 5, and 7, the total length of the metatarsal rudiments, as well as the length of the calcified diaphysis were measured. Histology of the tissue was performed to examine its vitality. The increase in length of the calcified diaphysis during 7 days of culture was significantly higher in the ultrasound-treated rudiments compared to the untreated controls (P = 0.006). The growth of the control diaphysis was 180 +/- 30 microm (mean +/- SEM), while the growth of the ultrasound-treated diaphysis was 530 +/- 120 microm. The total length of the metatarsal rudiments was not affected by ultrasound treatment. Histology revealed a healthy condition of both ultrasound-treated and control rudiments. In conclusion, low-intensity ultrasound treatment stimulated endochondral ossification of fetal mouse metatarsal rudiments. This might be due to stimulation of activity and/or differentiation of osteoblasts and hypertrophic chondrocytes. Our results support the hypothesis that low-intensity ultrasound activates ossification via a direct effect on osteoblasts and ossifying cartilage.

Malunited ankle fractures. The late results of reconstruction.

We have analysed 31 malunited ankle fractures treated by reconstructive osteotomies. In all cases the malunited fibula has been corrected; this has been combined with other osteotomies and with fixation of ununited fragments as indicated. Our results show that, unless function was severely impaired, reconstruction was always worth while, no matter how long ago the injury had occurred and even if there were already arthritic changes.