Purpose
The incidence of anteroposterior overhang of the tibial component after TKA and its effect on clinical outcome were investigated, and the morphometric characteristics of the knees in which ...tibial baseplates were oversized were identified.
Method
One hundred and fourteen consecutive TKAs were retrospectively assessed. The dimensions of the tibia were measured on a pre-operative CT scan and were compared with those of the implanted tibial component. We analysed the effect of anteroposterior and mediolateral size variations on clinical outcomes 1 year after surgery.
Results
An anteroposterior overhang was observed in 87 % of cases on the lateral plateau, in 88 % on the central plateau and in 25 % on the medial tibial plateau. The mean post–pre-operative size differences were 3.2 ± 2.7, 2.8 ± 2.7 and −1.6 ± 2.3 mm, respectively. (Positive value means oversizing). A mediolateral overhang of the tibial component was found in 61 % of the patients. Oversizing was significantly greater and more frequent in females. Patients oversized in the anteroposterior dimension had lower post-operative pain scores. Patients with mediolateral oversizing had decreased flexion 1 year after surgery. Anteroposterior oversizing was observed more frequently in patients with asymmetric tibial plateaus, while mediolateral oversizing was observed more frequently in patients with small tibias.
Conclusions
This study demonstrates that the incidence of oversized tibial plateau components is surprisingly high and that functional outcomes are lower in the case of mediolateral or anteroposterior oversizing. The risk of oversizing could be predicted as it occurs predominantly in patients with asymmetric proximal tibia and/or small tibia.
Level of evidence
IV.
Purpose
Manufacturers of total knee arthroplasty (TKA) have introduced narrower femurs to improve bone-implant fit. However, few studies have reported the clinical consequences of mediolateral ...oversizing. Our hypothesis was that component oversizing negatively influences the results after TKA.
Methods
One hundred and twelve prospectively followed patients with 114 consecutive TKA (64 females and 50 males) were retrospectively assessed. The mean age of the patients was 72 years (range, 56 to 85 years). The dimensions of the femur and tibia were measured on a preoperative CT-scan and were compared with those of the implanted TKA. The influence of size variation on the clinical outcomes 1 year after surgery was assessed.
Results
Mediolateral overhang was observed in at least one area in 66 % of the femurs (84 % in females and 54 % in males) and 61 % of the tibia (81 % in females and 40 % in males). Twenty-two patients presented no overhang in any area and 16 had overhang in all studied zones. The increase in the Pain and KOOS scores were 43 ± 21 and 36 ± 18 in the patients without overhang and 31 ± 19 and 25 ± 13 in patients with overhang (
p
= 0.033;
p
= 0.032). Knee flexion was 127° ± 7 and 121° ± 11, respectively. Regression and latent class analysis showed a significant negative correlation between overall oversizing and overall outcome.
Conclusions
This study confirms that oversizing may lead to worse clinical results in TKA. The clinical consequences are that surgeons should pay attention not to oversize implants during implantation nd that oversizing should be ruled out in case of so called unexplained pain.
Level of evidence
IV.
Purpose
The purpose was to estimate the prevalence of popliteus tendon impingement following TKA, and to describe the characteristics and the differential diagnosis protocol for this rare condition. ...The hypothesis was that arthroscopic popliteal tenotomy in TKA patients with suspected popliteus tendon impingement would relieve pain and improve satisfaction.
Methods
Of 741 TKAs performed over three years, eight (1.1%, all women) had suspected popliteus tendon impingement, of which seven had severe localised posterolateral knee pain and one global knee pain. Upon confirmation of popliteus tendon impingement, arthroscopic popliteal tenotomy was performed, and outcomes (Pain on visual analogue scale (pVAS; best, 0; worst, 10), Oxford Knee Score (OKS; best, 48; worst, 0) and satisfaction (best, 100%; worst, 0%) assessed at mean 18-month follow-up.
Results
At four to 30 months after TKA, arthroscopic exploration revealed popliteus tendon impingement in all eight knees. Six reported complete pain relief (pVAS, 0) the day following arthroscopic popliteal tenotomy, whilst one reported some residual pain (pVAS, 2). The remaining patient with global pain reported no pain relief, and required revision TKA at 12 months. Excluding the revised TKA, OKS was between 19 and 43, and satisfaction was rated ≥ 80% in five of the remaining seven patients.
Conclusions
Arthroscopic popliteal tenotomy relieved symptoms in TKA patients with persistent localised posterolateral pain and a positive popliteus test. These findings suggest that the popliteus test is reliable to diagnose popliteus tendon impingement following TKA, which could be treated by arthroscopic popliteal tenotomy.
Level of evidence
Level IV, Small case series.
The objective of this paper is to reflect broadly on the meaning of June 4 in the history of contemporary China. The main idea is that the violent military and political repression of the 1989 ...Chinese Pro-Democracy Movement in Beijing and in other cities is not only a tragic event which shocked the whole world, but also, looking at it in retrospect, a breaking point in the history of contemporary China. The fracture which it generated is not only affecting time, by drawing a fault line between the period of the 1980s and the following period, but is also affecting space, because the turn which China took at this time was in total contradiction with the events which started in the communist countries in eastern Europe and Russia in the same year and led to loss of power for the Communist parties of these countries. This means that the June 4 massacre cut China not only from its rather optimistic period of the 1980s, but also from the rest of the (hitherto) communist world. But the paradox is that this fundamental event has been, through the extraordinary efforts of the Chinese Communist Party (CCP), transformed into a non-event, which has been almost totally erased not only from all official record including books, textbooks and all kinds of media, but also from the collective memory of the population.
Little is known about the survival of total hip arthroplasty implants with bioactive coatings beyond the first 20 years. The authors aimed to report survival of a tapered hip stem fully coated with ...hydroxylapatite (HA) at follow-up of 25-30 years.
Of the original series of 320 patients (347 hips), 12 patients (12 hips) had stem and cup revisions, 54 patients (55 hips) had cup revisions, 17 patients (17 hips) had liner exchange. A total of 207 patients (225 hips) died with stems in place and 21 patients (24 hips) could not be reached. This left a cohort of 80 patients (86 hips) with their original stem for assessment. Survival was analyzed using the Kaplan-Meier (KM) method and cumulative incidence function (CIF).
Considering stem revision as endpoint, the revision risk calculated using the KM method was 6.3%, whereas using the CIF it was 3.7%. Considering any reoperation as endpoint, the revision risk calculated using the KM method was 41.2%, whereas using the CIF it was 25.9%. The Harris Hip Score for 77 patients (18 hips) was 81.6 ± 15.2. Standard x-rays were available for 52 hips (49 patients), and 10 (19.2%) showed radiolucencies <2 mm thick.
This study is the first to report outcomes of an HA-coated stem beyond 25 years. The survival of stem compares favorably with long-term survival of the Charnley cemented stem, and with shorter-term registry studies. The stem achieved its intended purpose of total osteointegration in the long-term, although the proximolateral region remains susceptible to radiolucencies.
We describe a method for planning total hip arthroplasty (THA) in patients with a displaced femoral neck fracture based on a simple CT scan protocol of the contralateral hip. This protocol was used ...on 22 consecutive patients during the inclusion period, followed by reconstruction and 2D templating to predict the implant size and positioning. The exact planned size was achieved in 21/22 (95%) cups, 14/22 (64%) femoral stems and 14/22 (64%) femoral heads. There were no intra- or postoperative fractures. After surgery in which this planning method had been applied, the differences in length and lateral offset were less than 5 mm on average relative to the opposite side (mean postoperative leg length difference of −2 mm (−8 to +3 mm) and lateralization of −4 mm (−14 to +3 mm)). While this technique exposes the patient to additional radiation, it does not require any specific devices or surgical approach and could be used in most hospitals.
IV.
The purpose of the present study was to update and report clinical outcomes and survival of primary total hip arthroplasty using a cementless double-tapered titanium fully hydroxyapatite-coated stem ...at a follow-up > 30 years.
The outcomes of this series of 347 primary total hip arthroplasties were already published at a follow-up > 25 years, during which only 12 stems were revised. Since then, there were two additional stem revisions, bringing the total to 14 stem revisions (all of which also required cup revision). Patients still living with the original stem were assessed using the modified Harris Hip Score and patient satisfaction (very satisfied, satisfied, dissatisfied, and very dissatisfied). Revision incidence was calculated using the Kaplan-Meier (KM) method and Cumulative Incidence Function (CIF) at 35 years.
At a mean follow-up of 33 years (range, 31 to 35 years), 32 patients (34 hips) were still living with the original stem. Their mean modified Harris Hip Score was 86 points (range, 46 to 100) and all patients (100%) were very satisfied or satisfied with surgery. The revision incidence at 35 years considering (a) stem revision for any reason was 9.5% using KM and 4.5% using CIF; (b) stem revision for aseptic loosening was 3.1% using KM and 2.1% using CIF; and (c) reoperation or revision of any component for any reason was 45.3% using KM and 26.3% using CIF.
The present study has demonstrated excellent survival at 35 years for a cementless double-tapered titanium fully hydroxyapatite-coated stem.
Level IV, Retrospective cohort study.
•The present study has demonstrated excellent long-term survival for a cementless double-tapered titanium fully hydroxyapatite-coated stem.•At 35 years, the Cumulative Incidence Function survival considering stem revision as an end point was 96%, while the Kaplan-Meier survival was 91%, which is comparable to the survival of other cementless stems, albeit at a longer follow-up.•Of the patients available for clinical assessment at 30 to 35 years, most had good or excellent Harris Hip Scores and all reported to be satisfied or very satisfied with total hip arthroplasty surgery.
Purpose
Residual pain during activities of daily living and/or at rest is a major cause of a patient’s dissatisfaction after total knee arthroplasty (TKA). The management of a painful TKA, which has ...no obvious clinical or radiological explanation, requires further investigation with more sensitive imaging modalities (CT scan and bone scan) and hematological tests. It is often challenging for the physician to determine what level of pain warrants these more complex and expensive medical examinations. A precise knowledge of the natural history of postoperative pain following TKA is therefore of fundamental importance.
Methods
We reviewed the literature and highlighted the studies that investigated the evolution of pain after uncomplicated TKAs and the impact of demographic and psychosocial variables on a postoperative painful TKA.
Results
Factors that are associated with a more painful knee include female sex, a younger age at the time of surgery, and a higher than normal depressive or anxiety state. In particular, the Pain Catastrophizing Scale (PCS), a scale that quantifies a patient’s negative or exaggerated orientation to pain, appears to significantly influence a patient’s outcome after TKA.
Conclusion
The identification of these high-risk patients is critical so that a surgeon can provide detailed preoperative education in order to give these patients a realistic expectation of their possible satisfaction following TKA.
Level of evidence
V.
Purpose
The purpose of this systematic review and meta-analysis was to investigate the variability in tibial geometric ratios among knees of different sexes and races to determine whether ...commercially-available tibial baseplates accommodate the morphologic diversity. The hypothesis was that anthropometric studies report considerable variability of tibial geometric ratios among sexes and races.
Methods
This systematic review and meta-analysis was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) criteria. Two authors independently conducted an electronic search using MEDLINE
®
and Embase
®
on 28 January 2021 for clinical studies reporting on tibial geometric ratios. Tibial geometric ratios, as reported by the clinical studies, were represented by plotting their means and two standard deviations for comparison to two symmetric and two asymmetric commercially-available tibial baseplates.
Results
A total of 27 articles that reported on a combined total of 20,944 knees were eligible for data extraction. Variation in tibial aspect ratios was equal among sexes. The greatest variation in aspect ratio was observed among East Asians, followed by Caucasians, African-Americans, Indian and Middle Easterns. The variation in tibial asymmetry ratio was larger among men compared to women. The greatest variation in asymmetry ratio was observed among African-Americans, followed by Caucasians, East Asians, Indian and Middle Easterns. Bone-implant mismatch of > 3 mm overhang or > 4 mm under-coverage with four commercially-available tibial baseplates occurred in large proportions of knees due to variations in aspect ratio (in 17–100% of knees) and asymmetry ratio (in 7–100% of knees).
Conclusion
Anthropometric studies reported considerable inter-individual variability of tibial geometric ratios, which exceeded effects of sexual dimorphism and racial diversity. Bone–implant mismatch may be unavoidable in a large proportion of knees, when considering that a surgeon generally only uses one or a few TKA brands. These findings support the drive towards patient-specific implants to potentially achieve accurate bone–implant fit by implant customisation.
Level of evidence
IV.
Purpose
To report the early clinical and radiographic outcomes of custom total knee arthroplasty (TKA) in knees that had prior osteotomies and/or extra-articular fracture sequelae.
Methods
The ...authors retrospectively analysed a consecutive series of 444 knees that received custom TKA between 2016 and 2019 and identified 41 knees that had prior extra-articular events (osteotomies or fracture sequelae). Patients responded to pre- and post-operative (> 12 months) questionnaires, including Knee Society Score (KSS), Oxford Knee Score (OKS), Forgotten Joint Score (FJS) and Knee injury and Osteoarthritis Outcome Score (KOOS). Net improvements were calculated by subtracting pre- from post-operative scores. In addition to a preoperative CT scan, pre- and post-operative long-leg weight-bearing radiographs were obtained, on which the hip–knee–ankle (HKA) angle, femoral mechanical angle (FMA, between femoral mechanical axis and joint line) and tibial mechanical angle (TMA, between tibial mechanical axis and joint line) angles were measured, and alignment was planned within a ‘target zone’ of FMA and TMA within 85°–95° and HKA angle within 175°–183°. Agreements between preoperative, planned and post-operative angles were calculated using intra-class correlation coefficients (ICC).
Results
From the initial 41 knees, 3 had incomplete post-operative data and 1 was revised for painful stiffness due to uncorrected rotational malunion, leaving 37 knees for analysis. Twenty had prior osteotomies (tibia,
n
= 18, femur,
n
= 2), 8 had isolated fractures (tibial,
n
= 3; femoral,
n
= 5), and 9 had both osteotomies and fractures. Postoperative coronal alignments were 90.4° ± 2.4° for FMA, 89.3° ± 2.6° for TMA and 179.9° ± 3.0° for HKA angle. Agreements between planned and achieved alignments were fair to excellent, and 29 (78%) knees were within the ‘target zone’. At a mean follow-up of 15 ± 5 months, all clinical scores had improved significantly (
p
< 0.001).
Conclusions
Custom TKA granted satisfactory clinical outcomes and a low complication rate in knees that had prior osteotomies and/or extra-articular fracture sequelae. Using custom implants and strategies for coronal alignment, 29 (78%) of the 37 knees were successfully aligned within the ‘target zone’, and 35 (95%) of the 41 knees did not require ligament release.
Level of evidence
IV.
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