The clinical outcome of total knee arthroplasty is compromised by a previously implanted medial unicondylar knee arthroplasty

OBJECTIVE

To investigate the clinical outcome of patients that underwent conversion of a medial unicondylar knee arthroplasty (UKA) to a total knee arthroplasty (TKA) and to compare that outcome to patients that underwent primary TKA. It was hypothesized that those groups would significantly differ in terms of knee score outcome and implant survival.

METHODS

A retrospective-comparative study was conducted utilizing data from the Federal state's arthroplasty registry. Included were patients from our department that undergone a conversion of a medial UKA to a TKA (UKA-TKA group). The Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) from preoperative and 1-year postoperative was used. Moreover, the implant survival was analyzed.

RESULTS

In the UKA-TKA group, there were 51 cases (age 67 ± 10, 74% women), and in the TKA group, there were 2247 cases (age 69 ± 9, 66% women). The one-year postoperative WOMAC total score was 33 in the UKA-TKA group und 21 in the TKA group (p < 0.001). Similarly, the WOMAC pain, WOMAC stiffness, and WOMAC function scores were significantly worse in the UKA-TKA. After 5 years, the survival rates were 82% and 95% (p = 0.001). The 10-years prosthesis survival was 74% and 91% in the UKA-TKA and TKA groups, respectively (p < 0.001).

CONCLUSIONS

Based on our findings it is concluded that patients who received a TKA after UKA have inferior results than those that directly receive a TKA. This is true for both patient-reported knee outcome and prosthesis survival. Converting UKA to TKA should not be seen as an easy operation, but should rather be done by surgeons with considerable experience in both primary and revision knee arthroplasty.

Imprecise prediction of implant sizes with preoperative 2D digital templating in total knee arthroplasty

PURPOSE

To analyze the match between preoperatively determined implant size (2D templating) and intraoperatively used implant size in total knee arthroplasty (TKA). Also examined were the factors that might influence templating accuracy (gender, surgeon experience, obesity, etc.).

MATERIALS AND METHODS

The study was retrospective and conducted in a specialized ENDOCERT arthroplasty center. Digital templating was done with the MediCAD software. If the planned and implanted TKA components (both femur and tibia) were the same size, the match was classified "exact." A deviation of ± one size (at the femur or tibia or both) was classified "accurate." A deviation of ± two or more sizes (at the femur or tibia or both) was classified "inaccurate." Obesity, gender, implant type and surgeon experience were investigated for potential influence on templating accuracy. Chi-square tests and Cohen's weighted kappa test were used for statistical analysis.

RESULTS

A total of 482 cases [33.6% male, 66.4% female, age 69 ± 11, body mass index (BMI) 30.3 ± 5.8] were included. When the femur and tibia were taken together, exact size match was observed in 34% (95% CI 29.9-38.3%) of cases, accurate size match in 57.5% (95% CI 53-61.8%) and inaccurate size match in 8.5% (95% CI 6.3-11.2%). Inaccurate size match prolonged operative time (p = 0.028). Regarding the factors potentially influencing templating accuracy, only gender had a significant influence, with templating being more accurate in men (p = 0.004). BMI had no influence on accuracy (p = 0.87). No effect on accuracy was observed for implant type and surgeon experience.

CONCLUSIONS

The accuracy of 2D size templating in TKA is low, even in a specialized ENDOCERT arthroplasty center. The study findings challenge the usefulness of preoperative 2D size templating and highlight the importance of more reliable templating methods.

LEVEL OF EVIDENCE

Level III (retrospective observational study).

MRI analysis of simple and aneurysmal bone cysts in the proximal humerus: what actually matters in clinical routine

OBJECTIVE

To evaluate magnetic resonance imaging (MRI) characteristics of simple and aneurysmal bone cysts (SBC/ABC) of the proximal humerus and the intermittent difficulty in the imaging differentiation between the two in daily clinical routine.

MATERIALS AND METHODS

MR images of 26 patients with suspected SBC/ABC in the proximal humerus were retrospectively assessed by two independent radiologists blinded to the final histological result. Based on a standard MRI protocol, different morphologic features and signal intensities of the lesion on non-enhanced and enhanced sequences were documented. The radiological diagnosis was correlated with histology.

RESULTS

Eighteen patients had the image-based diagnosis of an SBC, yet the histology confirmed only 12, the residual 6 were identified as an ABC, despite the imaging criteria corresponding unambiguously to the former. One of the main reasons was the unicameral morphology of lesions, found in 9/14 (64.3%) cases of all ABCs, i.e., in 19/26 cases in total. Therefore, the sensitivity of the radiological diagnosis was moderate (57.14%), yet specificity very high (100%). In total, 69.2% (18/26) presented with a pathological fracture at admission, which correlated strongly with both circumferential (MCC = 0.65, p = 0.01) and septal (MCC = 0.42, p = 0.06) enhancement patterns. Circumferential enhancement was also found to correlate strongly with the histological diagnosis, being recognized in all cases of ABC (MCC = 0.44, p = 0.06).

CONCLUSION

MRI characteristics of ABCs/SBCs in the proximal humerus are indifferent and ABCs may morphologically present as SBCs. Radiologists should be aware of the different, often confusing presentation of both entities in daily clinical routine.

[A multidimensional v-shaped distalizing osteotomy of the tibial tuberosity with a proximal buttress ("coffin-shaped" osteotomy)]

The aim of the intervention presented is a distalization of the tibial tuberosity. It is indicated in patients with symptomatic patella alta, i.e. patients with instability of the patella. It facilitates a V-shaped osteotomy. The bone gained during distalization is used as a proximal buttress. This leads to an improved mediolateral and proximal stability. The bony surface area is increased, which improves bony healing. There were no secondary dislocations in the patient group of 10 patients treated by the surgeon.

Telemedicine versus on-site treatment at a surgical university clinic: Study of 225 consecutive patients

INTRODUCTION

Recently, telemedical services are increasingly used. It remains unclear, if outpatients in general surgery can be treated via telemedicine (e.g. telework). We aimed to evaluate, if diagnosis and therapies of outpatients in general surgery can be found using a mobile healthcare communication app instead of personal contact.

MATERIAL AND METHODS

In a prospective, double blind, anonymized clinical study we included consecutive outpatients at a general surgery department at a university hospital. For the telemedical "treatment" the on-site doctors uploaded variables (e.g. anamnesis, radiograph, etc.) for each patient. The telemedical doctor received the information only via app and did not see the patient physically. Both, the doctor on-site and the virtual telemedical-doctor then uploaded the diagnosis and their suggested therapy - blinded to each other. The outpatient received the on-site treatment only. The virtual treatment was solely for scientific purposes and had no therapeutic impact.

RESULTS

225 consecutive surgical outpatients (53 % female and 47 % male) were included. Mean age was 61 years. In 84 % of cases the telemedical diagnosis matched the on-site diagnosis. The telemedical treatment was not inferior as compared to the on-site treatment in 94 % of all cases and the same therapy was proposed in 76 %. In 6% of all cases the telemedical therapeutic regimen could possibly harm or lead to an over- or under treatment of the patient.

CONCLUSION

Telemedical consultation seems to work in the field of general surgery. Telemedicine in general surgery potentially could decrease waiting time for an appointment and patient frequency. However, the potential harm of a wrong therapy remains due to the lack of a clinical observation.

Surgical Treatment of Localized-Type Tenosynovial Giant Cell Tumors of Large Joints: A Study Based on a Multicenter-Pooled Database of 31 International Sarcoma Centers

BACKGROUND

Localized-type tenosynovial giant cell tumor (TGCT) is a rare, neoplastic disease with only limited data supporting treatment protocols. We describe treatment protocols and evaluate their oncological outcome, complications, and functional results in a large multicenter cohort of patients. A secondary study aim was to identify factors associated with local recurrence after surgical treatment.

METHODS

Patients with histologically proven localized TGCT of a large joint were included if they had been treated between 1990 and 2017 in 1 of 31 tertiary sarcoma centers. Of 941 patients with localized TGCT, 62% were female. The median age at initial treatment was 39 years, and the median duration of follow-up was 34 months. Sixty-seven percent of the tumors affected the knee, and the primary treatment at the tertiary center was 1-stage open resection in 73% of the patients. Proposed factors for predicting a first local recurrence after treatment in the tertiary center were tested in a univariate analysis, and those that demonstrated significance were subsequently included in a multivariate analysis.

RESULTS

The localized TGCT recurred in 12% of all cases, with local-recurrence-free rates at 3, 5, and 10 years of 88%, 83%, and 79%, respectively. The strongest factor for predicting recurrent disease was a prior recurrence (p < 0.001). Surgical treatment decreased pain and swelling in 71% and 85% of the patients, respectively, and such treatment was associated with complications in 4% of the patients. Univariate and multivariate analyses of the patients who had not undergone therapy previously yielded positive associations between local recurrence and a tumor size of ≥5 cm versus <5 cm (hazard ratio [HR] = 2.50; 95% confidence interval [CI] = 1.32 to 4.74; p = 0.005). Arthroscopy (versus open surgery) was significantly associated with tumor recurrence in the univariate analysis (p = 0.04) but not in the multivariate analysis (p = 0.056).

CONCLUSIONS

Factors associated with recurrence after resection of localized-type TGCT were larger tumor size and initial treatment with arthroscopy. Relatively low complication rates and good functional outcomes warrant an open approach with complete resection when possible to reduce recurrence rates in high-risk patients.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Results of universal ultrasound screening for developmental dysplasia of the hip: a prospective follow-up of 28 092 consecutive infants

AIMS

The purpose of this study was to analyze the incidence of the different ultrasound phenotypes of developmental dysplasia of the hip (DDH), and to determine their subsequent course.

PATIENTS AND METHODS

A consecutive series of 28 092 neonates was screened and classified according to the Graf method as part of a nationwide surveillance programme, and then followed prospectively. Abnormal hips were followed until they became normal (Graf type I). Type IIb hips and higher grades were treated by abduction in a Tübinger orthosis until normal. Dislocated hips underwent closed or open reduction.

RESULTS

Overall, 90.2% of hips were normal at birth. Type IIa hips (8.9%) became normal at a median of six weeks (interquartile range (IQR) 6 to 9). Type IIc and IId hips (0.67%) became normal after ten weeks (IQR 7 to 13). There were 19 type lll and eight type lV hips at baseline. There were 24 closed reductions and one open reduction. No late presentations of DDH were detected within the first five years of life.

CONCLUSION

The incidence of DDH was eight per 1000 live births. The treatment rate was 1% (n = 273). The rate of first operations on the newborn hip was 0.86, and rate of open surgery was 0.04. The cumulative rate of open surgery was 0.07. The authors take the view that early identification and treatment in abduction of all dysplastic hips in early childhood reduces the rate of open reduction and secondary DDH-related surgery later in life. Cite this article: Bone Joint J 2018;100-B:1399-1404.