Trends in unicompartmental knee arthroplasty among 138 international experienced arthroplasty knee surgeons

Purpose

Unicompartmental knee arthroplasty (UKA) is an established option for treating isolated unicompartmental knee osteoarthritis (OA), but controversies still exist about patient selection, indications, perioperative management and alignment goals. This survey was designed to understand the current trends of experienced arthroplasty knee surgeons performing UKA.

Methods

An online questionnaire was created with SurveyMonkey® to assess global tendencies in the utilization of UKA. A link to the survey was shared with all ESSKA (European Society for Sports Traumatology, Knee Surgery and Arthroscopy) members. The questionnaire consisted of free and multiple-choice questions and was divided into four sections: demographic information, the surgical activity of the respondents, indications for surgery and postoperative alignment goals.

Results

A total of 138 ESSKA members from 34 different countries completed the survey. A total of 81 % of the responders performed fewer than 50 UKAs per year; 53 % of UKAs represented less than 20 % of their knee replacements; 71 % used mainly or only fixed-bearing implants; 81 % performed UKA in a shorter time compared to TKA; and 61 % and 72 % were interested in custom-made UKA and robotics, respectively. Thirty-six percent considered a minimum postoperative alignment of 0° for medial UKA, and 32 % considered 10° as the maximum valgus deformity for lateral UKA. Fifty-five percent had no minimum age cut-off, 47 % had no BMI cut-off, and 57 % believed TKA was better than UKA in knees with concomitant high-grade patellofemoral OA. Approximately 50 % of the surgeons desired a coronal alignment that was the same as the predegeneration alignment.

Conclusion

A high level of agreement was reached regarding the following: preference for fixed-bearing UKAs, lower surgical time for UKA compared to TKA, interest in custom-made and robotic UKAs, no age and weight cut-off, TKA preferred in the presence of patellofemoral OA, and a final alignment goal of the predegenerative state both for medial and lateral. There was no agreement regarding length of stay, rehabilitation protocol, preoperative varus and valgus cut-off values, and treatment in cases of absence of anterior cruciate ligament or previous osteotomy.

Prevention of Periprosthetic Joint Infection in Total Hip and Knee Replacement: One European Consensus

Periprosthetic joint infection (PJI) is a devastating complication in total hip and knee replacement. Its prevention is key to decrease the incidence and avoid some consequences that seriously impact patients and health systems. In view of the variety of recommendations and guidelines, we decided to conduct an expert, peer-reviewed European consensus analysis about the pre-, intra-, and postoperative prevention of PJI. A multinational group of practicing orthopedic experts developed a series of 47 consensus statements in 6 main groups of intervention, and a 2-stage Delphi approach was launched with a threshold for agreement at 75% and for very high agreement at more than 90%. A total of 306 orthopedic surgeon responses were gathered from 9 countries. Consensus was reached for 42/47 statements, 31/47 of which achieved a very high consensus. Many preoperative actions gathered strong consensus, although areas like the use of alcoholic chlorhexidine or the timing of hair removal did not attain strong consensus, despite available evidence. Intra- and postoperative actions showed more variability regarding incise drapes, skin suturing techniques, and wound follow-up. This study confirms an important consensus among orthopedic surgeons across Europe in many areas well known to contribute to the prevention of PJI; however, there are still grounds for improvement.

Clinical and surgical outcomes of robot-assisted versus conventional total hip arthroplasty: a systematic overview of meta-analyses

Robot-assisted total hip arthroplasty (THA), in comparison to conventional THA, improves radiographic outcomes, but it remains unclear whether it alters complication rates, clinical and functional outcomes, and implant survival.

The purpose of this systematic overview was to summarize the findings of the most recent meta-analyses that compare clinical and surgical outcomes of robot-assisted versus conventional THA.

Two readers independently conducted an electronic literature search, screening and data extraction from five electronic databases. Inclusion criteria were: meta-analyses evaluating robot-assisted versus conventional THA in terms of radiographic outcomes, clinical and functional scores, and complications and revision rates. The literature search returned 67 records, of which 14 were duplicates and 49 were excluded, leaving three meta-analyses published within the past two years for data extraction and analysis.

The present overview of meta-analyses suggests that, compared to conventional THA (n = 3011), robot-assisted THA (n = 1813) improves component placement and reduces intraoperative complications. The overview also affirms that robot-assisted THA could extend surgery by 20 minutes, and increases risks of postoperative heterotopic ossification, dislocation, and revision. None of the meta-analyses found significant differences in clinical or functional scores between robot-assisted and conventional THA.

Future studies and reviews should make a clear distinction between active and semi-active robotic assistance, address technology matureness, and describe the experience of surgeons with robotic assistance.

Cite this article: EFORT Open Rev 2021;6:1157-1165. DOI: 10.1302/2058-5241.6.200121

No significant difference in early clinical outcomes of custom versus off-the-shelf total knee arthroplasty: a systematic review and meta-analysis

PURPOSE

The purpose of this systematic review and meta-analysis was to collect, synthesise and critically appraise findings of clinical studies that report outcomes of custom total knee arthroplasty (TKA). The hypothesis was that, compared to off-the-shelf (OTS) TKA, custom TKA would yield better surgical, clinical and radiographic outcomes.

METHODS

This systematic review and meta-analysis was performed in accordance with the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). On 8 February 2021, two authors independently searched and screened articles using MEDLINE®, Embase® and the Cochrane Library without restriction on date of publication. Findings from eligible articles were narratively synthesised and tabulated, and when ≥ 3 comparative studies reported the same outcome, results were pooled and summarised in forest plots. Quality assessments of the studies were done according to the guidelines of the Joanna Briggs Institute (JBI) Checklists.

RESULTS

A total of 15 articles were eligible for data extraction, of which 9 were case-control studies reporting on 929 custom versus 998 OTS TKA, 5 were case series reporting on results of 587 custom TKA, and 1 was a cross-sectional study reporting on results of 44 custom versus 132 OTS TKA. Five studies that compared early revision rates found the overall effect in favour of OTS TKA (odds ratio (OR), 0.4; p = n.s.) but the result did not reach statistical significance. Four studies found no statistically significant difference in KSS knee (standardised mean difference (SMD), - 0.10; p = n.s.) and function (SMD, 0.03; p = n.s.), and five studies found no statistically significant difference in range of motion (SMD, 0.02; p = n.s.). One study that compared bone-implant fit between custom and three OTS tibial components found no overhang but revealed under-coverage of up to 18% in knees with custom tibial baseplates.

CONCLUSION

Custom TKA demonstrated no significant benefits compared to OTS TKA in terms of pooled clinical outcomes, but had considerably higher early revision rates. The findings of the present systematic review and meta-analysis suggest the need for studies with better comparable groups and standardisation of reporting outcomes amongst studies, that could increase the quality of evidence and enable pooling of results in future meta-analyses.

LEVEL OF EVIDENCE

Level IV.

Twenty-one sports activities are recommended by the European Knee Associates (EKA) six months after total knee arthroplasty

PURPOSE

To elaborate recommendations for sports participation following TKA among the members of the European Knee Associates (EKA).

METHODS

A prospective online survey was conducted among the members of the European Knee Associates (EKA). The European Knee Associates (EKA) are a section of the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA). The survey investigated recommendations for 47 sports disciplines. Possible answers were: allowed, allowed if experienced, not allowed, no opinion. The survey was conducted separately for 4 specific time frames: within 6 weeks after TKA; 6-12 weeks after TKA; 3-6 months after TKA; and more than 6 months after TKA. Consensus among the respondents was then analyzed.

RESULTS

EKA members (N = 120) participated in the survey. A high level of consensus was reached for a recommendation to allow 5 different sports in the first 6 weeks after TKA, 7 sports 6-12 weeks after surgery, 14 sports 3-6 months after TKA, and 21 out of 47 activities 6 months after surgery. In the first 6 weeks after TKA walking, stair climbing, swimming, aqua fitness, and static cycling were recommended. Six to twelve weeks after TKA, cycling on level ground and yoga were recommended in addition to the aforementioned activities. Further sports activities recommended beyond 12 weeks after TKA were: tennis doubles, golf, fitness/weight lifting, aerobics, hiking, Nordic walking and sailing. The sport for which the recommendation was "not allowed" following TKA was squash.

CONCLUSION

The number of sports recommended by EKA surgeons increases stepwise over the postoperative time frames. The findings are regarded as clinically relevant as they may serve as a basis for answering patient questions on timing and giving recommendations for the resumption of sports activities following standard primary TKA and should be individualized by surgeons for their patients' expectations and goals.

LEVEL OF EVIDENCE

V.

Comparable clinical outcome and implant longevity after CT- or MRI-based patient-specific instruments for total knee arthroplasty: a 2-year follow-up of a RCT

PURPOSE

Patient-specific instruments (PSI) are already widespread used in total knee arthroplasty (TKA). Either computed tomography (CT) scans or magnetic resonance imaging (MRI) scans are used pre-operatively to create jigs to guide resection during surgery. This study is a sequel of previous work that showed significantly more radiological outliers for posterior slope when CT-based guides were used. The aim of this study was to assess differences in revision rate and clinical outcome between the two groups at 2-year follow-up.

METHODS

At the 2-year follow-up, 124 patients were analysed in this prospective, randomised single-blind study. A survival analysis with revision of the TKA as endpoint was performed. Patients fulfilled four patient-reported outcome measurements (PROMs). Scores on the questionnaires were compared between both groups at the different follow-up visits.

RESULTS

At final follow-up, there was no significant difference in the survival rates of the CT- and MRI-based PSI surgery. Postoperatively, the PROMs significantly improved within each group compared with the pre-operative values. There were no significant differences for the PROMs between both groups at the 2-years follow-up.

CONCLUSIONS

Although previous results showed more outliers regarding posterior slope for CT-based PSIs, no difference in revision rate or the outcome of PROMs was found at 2-year follow-up. Further research to determine what the influence is of radiological outliers on implant survival and clinical outcomes is necessary.

LEVEL OF EVIDENCE

I.

Patient-specific guide for revision of medial unicondylar knee arthroplasty to total knee arthroplasty: beneficial first results of a new operating technique performed on 10 patients

BACKGROUND AND PURPOSE

Unicompartmental to total knee arthroplasty revision surgery can be technically demanding. Joint line restoration, rotation, and augmentations can cause difficulties. We describe a new technique in which single-way fitting guides serve to position the knee system cutting blocks.

METHOD

Preoperatively, images of the distal femur and proximal tibia are taken using CT scanning. These images are used to create a patient-specific guide that fits in one single position on the contours of the bone and the prosthesis in situ. The guides are fixed with pins and then removed. The pins determine the position of the cutting blocks. 10 consecutive revisions were performed using this technique.

RESULTS

All guides fitted well. 7 of 10 femoral prostheses were within the desired AP and sagittal angle ± 3°. However, 1 proximal tibia did not have enough bone stock on the medial plateau for adequate fixation of the guide, so conversion to intramedular referencing was performed. This was to be expected after the preoperative planning. All tibial components were within the desired AP angle ± 3° and 7 of 10 were within the desired sagittal angle. Hip-knee-ankle angle was within 0 ± 3° in 8 of 10 cases.

INTERPRETATION

This new technique makes preoperative planning and execution of this plan during surgery less demanding. Problems such as the need for augmentations can be predicted at the preoperative planning. The instrumentation must be redesigned in order to make this technique work in cases where there is minimal bone stock present.

Tendoscopy of the peroneal tendons

An anatomic cadaver study was performed. Subsequently, in a prospective study, diagnostic and therapeutic tendoscopy (tendon sheath endoscopy) was performed in nine consecutive patients with a history of persistent posterolateral ankle pain for at least 6 months. All patients had pain on palpation over the peroneal tendons, a positive peroneal tendon resistance test, and most often local swelling. In two patients, a peroneal click was found without symptoms of dislocation of the tendons over the fibula. The indications for arthroscopy were diagnostic procedure postsurgery (3), diagnostic procedure postfracture (2), snapping sensation (2), removal of exostosis (1), and partial tendon rupture (1). Inspection and surgery of both tendons and tendon sheath could be performed well by a standard two-portal technique. A new finding is the vincula that was consistently present in all our autopsy specimens, as well as in all our patients. The vincula attaches both tendons to each other and to the tendon sheath. At a mean follow-up of 19 months, three of the four patients in which adhesions were found and resected were symptom free. In one patient, a symptomatic prominent peroneal tubercle was successfully removed. One patient had a longitudinal rupture of the peroneus brevis tendon that was successfully sutured. There were no complications.

Tendoscopy of the posterior tibial tendon

An anatomic cadaver study was performed and subsequently, in a prospective study, diagnostic and therapeutic tendoscopy (tendon sheath endoscopy) was performed in 16 consecutive patients with a history of persistent posteromedial ankle pain for at least 6 months. All patients had pain on palpation over the posterior tibial tendon, a positive tibial tendon resistance test, and local swelling. The indications were diagnostic procedure after surgery in 5 patients, diagnostic procedure after fracture in 5, diagnostic after trauma in 1, chronic tenosynovitis in 2, screw removal in 1, and posterior ankle arthrotomy in 2 patients. Inspection and surgery of the complete tendon and its tendon sheath can be performed by a standard two-portal technique. A new finding is the vincula that was consistently present in all our autopsy specimens as well as all our patients. At 1-year follow-up, 3 of the 4 patients in whom resection of a pathological thickened vincula, and 2 patients in whom tenosynovectomy and tendon sheath release were performed, were free of symptoms. Other procedures such as removal of adhesions and screw removal could well be performed. In 2 patients with a posteromedially located loose body, successful removal took place by means of a posterior tibial tendoscopic approach. There were no complications.