Aim of the study The aim of this case–control study was to develop a clinical decision rule to support assessment of the risk of long-bone non-union and plan for appropriate early intervention. Methods Two hundred patients (100 cases and 100 controls) were recruited. Risk factors identified to contribute to the development of non-union were recorded and analysed with a multivariable logistic regression model. Tabulation of the outcome (non-union/union) against each risk factor in turn (univariable analysis) was carried out. Odds ratios and confidence intervals were derived using Wald’s method. A receiver–operator curve was calculated and the area under the curve was computed. Having established the eight most important risk factors, a non-union risk index was developed as the count of the risk factors present in each patient. Results The five risk factors for non-union with greater effect size were post-surgical fracture gap > 4 mm (odds ratio (OR) = 11.97 95% CI (4.27, 33.53)), infection superficial/deep (OR 10.16 (2.44, 42.36)), not optimum mechanical stability (OR 10.06 (3.75, 26.97)), displacement > 75% of shaft width (OR 6.81 (2.21, 20.95)), and site of fracture—tibia (OR 4.33 (1.32, 14.14)). The ROC curve for the non-union index was 0.924, sensitivity 91%, specificity 77%. Conclusions The non-union index derived from counting risk factors predicts union for 0–4 risk factors and non-union for 5–8 risk factors. It can be readily applied and can guide clinicians about the risk of development of long-bone non-union. It can become a powerful aid for assessing fracture fixation outcome and to support early intervention.

Objective: To analyze the outcomes of tibial shaft fractures treated with a lateral parapatellar approach in the semiextended position for intramedullary nail insertion. Design: Prospective cohort study. Setting: Level I trauma center. Patients and Methods: Seventy patients treated from March 2012 to July 2015 with intramedullary nailing (IMN) using an extraarticular lateral parapatellar approach in the semiextended position were reviewed. Patients were clinically and radiographically checked at a minimum follow-up of 24 months, and the following data were recorded: fracture healing, any residual deformity, nail–apex distance, range of motion of the treated knee together with the contralateral side, knee functional outcome, and residual knee pain. Results: Twenty-four months after surgery, all patients were clinically and radiographically healed, with 2 cases of malalignment (angular deformity <10 degrees). The average range of motion of the treated knee was 0–130.6 degrees (±8.6 degrees) compared with 0–131.1 degree (±7.9 degrees) of the contralateral. Lysholm knee score was excellent for 57 patients, good for 11, and fair for 2. The mean residual pain was 0.6 (±1.1) according to the visual analogue scale. Conclusions: The described technique represents an effective option for IMN of tibial fractures. It is suitable for all tibial fractures, including proximal and distal. The results of our series demonstrate the effectiveness of this technique with nearly complete recovery of knee function and negligible incidence of anterior knee pain at a minimum follow-up of 24 months. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.