Analysis of causes for revision in unicompartmental knee arthroplasty.

The study by Zhao et al identifies the factors leading to the failure of unicompartmental knee arthroplasty (UKA) in their patients. These factors include substandard suturing of the wound, the presence of osteophytes and intra-articular loose bodies causing impingement, premature loosening of the tibial component, choosing unsuitable patients for the procedure, dislocation of the movable insert, and damage to the anterior cruciate ligament and medial collateral ligament. The findings suggest that employing the correct surgical techniques and indications is essential for successful outcomes in the UKA.

Association between nutritional scores and multilevel vertebral involvement in tubercular spine: a retrospective cohort study.

OBJECTIVE: The objective of this study is to evaluate the prognostic value of nutritional scores comprising the Controlling Nutritional Status (CONUT) score and the Prognostic Nutritional Index (PNI), in prediction of multilevel vertebral involvement (> 2 vertebra) in Spinal Tuberculosis (STB). METHODS: Retrospective analysis of 39 STB patients was conducted to assess nutritional indices (CONUT and PNI) and the numbers of vertebral affection. Spearman's correlation was used to examine the association between these variables. Receiver Operating Characteristic (ROC) curves were utilized to determine optimal cutoff values, with Area Under the Curve (AUROC) evaluation. Additionally, multiple logistic regression was performed as a predictive model. RESULTS: There were 24 males and 15 females, with a mean BMI of 18.88 kg/m² (± 1.37). Spearman's correlation analysis revealed negative correlations between BMI, PNI (rho - 0.68, p < 0.001) and multilevel vertebra involvement, while ESR (rho 0.83, p < 0.001), CRP (rho 0.81, p < 0.001), and CONUT score (rho 0.83, p < 0.001) positively correlated with multilevel vertebral affection (> 2 vertebra). Age and comorbidities showed no correlation with the level of vertebral affection. ROC analysis revealed a CONUT Score ≥ 3 cutoff (sensitivity-95.7%, specificity-87.5%) and PNI ≤ 38.605 (sensitivity-78.3%, specificity-93.8%) for predicting multilevel STB (> 2). PNI exhibited superior specificity and positive predictive value where as CONUT score was a better parameter for sensitivity, negative predictive value and diagnostic accuracy. Both CONUT score and PNI were significant predictors of vertebral involvement in univariate analysis, with multivariate analysis identifying CONUT score as the sole predictor of multilevel vertebral affection. CONCLUSION: Nutritional scores, including CONUT score and PNI, emerged as significant predictors of multilevel STB. CONUT score displayed superior sensitivity, negative predictive value, and overall diagnostic accuracy, while PNI served as a nutritional marker with high specificity and positive predictive value in predicting multilevel involvement in spinal tuberculosis.

Reconstruction of the extensor mechanism using polypropylene mesh in a displaced pathological fracture of the patella affected by giant cell tumour.

A man in his 30s came to our clinic with a year-long history of progressive pain and swelling in his knee. Diagnostic imaging revealed a displaced patellar fracture with an osteolytic, septated lesion and thinned expanded cortex in both fracture fragments. A core needle biopsy confirmed the diagnosis of giant cell tumour. Treatment involved wide excision of the tumour and the use of polypropylene mesh and a peroneal longus tendon autograft to reconstruct the extensor mechanism of the knee joint. One year postoperatively, the patient experienced no pain, demonstrated full range of motion and showed no signs of functional impairment or local tumour recurrence. This case highlights that reconstruction of the extensor mechanism of the knee after tumour excision with synthetic mesh is an affordable, user-friendly and widely accessible method. It can address large defects effectively while minimising the risks of disease transmission and graft lengthening, resulting in satisfactory outcomes.

Impact of limb length discrepancy on functional outcome in total knee arthroplasty patients: a prospective cohort study.

BACKGROUND: Limb length alteration following total knee arthroplasty (TKA) has been under-reported. Few studies have shown a significant association between limb length discrepancy (LLD) and poor functional outcome. This prospective study evaluated the impact of radiographic and perceived LLD on functional outcome in TKA. The variables affecting LLD were also evaluated. METHODS: The preoperative and postoperative limb lengths of TKA patients (112 knees, 81 patients, KL grade ≥ 3) were measured in full-length digital radiographs. The Hip-Knee-Ankle (HKA) angles were also measured. The functional outcome (Western Ontario and McMaster Universities Arthritis Index) and perception about LLD were evaluated after six months. RESULTS: The mean preoperative radiographic LLD in the unilateral and bilateral TKA groups was 0.75 cm ± 0.60 cm and 0.58 cm ± 0.52 cm (P = 0.197), respectively. Similarly, postoperative LLD was 0.76 cm ± 0.85 cm in the unilateral group and was 0.59 cm ± 0.92 cm (P = 0.402) in the bilateral group. Only 19.7% of patients had postoperative radiographic LLD of ≥ 10 mm, and 80.2% of patients had LLD of < 10 mm. The functional outcome was significantly affected when LLD exceeded 10 mm (correlation coefficient 0.54, P < 0.001). Linear regression analysis revealed no significant effects of age, sex, height, weight, BMI, preoperative LLD and difference in deformity between the limbs on postoperative LLD. 34.5% of patients perceived LLD in the preoperative period, which decreased to 3.7% in the postoperative period. Perceived LLD did not correlate to radiographic LLD and functional outcome. CONCLUSIONS: There is no significant difference in radiographic LLD between unilateral and bilateral TKA. The functional outcome is adversely affected by radiographic LLD of ≥ 10 mm. Age, sex, BMI, preoperative LLD and difference in deformity angle do not affect the LLD. About one-third of patients perceive LLD in the preoperative period, which improves significantly after TKA. LEVELS OF EVIDENCE: II.

Limb length discrepancy after total knee arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Limb length discrepancy (LLD) after total knee arthroplasty (TKA) has been considered as one of the reasons for the unsatisfactory outcome. However, there is no consensus about the extent of LLD that can be considered as clinically relevant. AIM: To evaluate the incidence of radiographic LLD and its impact on functional outcome following TKA. METHODS: All randomized-controlled trial and observational studies on LLD in TKA, published till 22nd June 2020, were systematically searched and reviewed. The primary outcome was "limb lengthening or LLD after TKA". The secondary outcomes included "assessment of LLD in varus/valgus deformity" and "impact of LLD on the functional outcome". RESULTS: Of 45 retrieved studies, qualitative and quantitative assessment of data was performed from eight studies and six studies, respectively. Five studies (n = 1551) reported the average limb lengthening of 5.98 mm. The LLD after TKA was ranging from 0.4 ± 10 mm to 15.3 ± 2.88 mm. The incidence of postoperative radiographic LLD was reported in 44% to 83.3% of patients. There was no difference in the preoperative and postoperative LLD (MD -1.23; 95%CI: -3.72, 1.27; P = 0.34). Pooled data of two studies (n = 219) revealed significant limb lengthening in valgus deformity than varus (MD -2.69; 95%CI: -5.11, 0.27; P = 0.03). The pooled data of three studies (n = 611) showed significantly worse functional outcome in patients with LLD of ≥ 10 mm compared to < 10 mm (standard MD 0.58; 95%CI: 0.06, 1.10; P = 0.03). CONCLUSION: Limb lengthening after TKA is common, and it is significantly more in valgus than varus deformity. Significant LLD (≥ 10 mm) is associated with suboptimal functional outcome.