Post Market Evaluation of Clinical Safety and Performance of the Fitbone Transport and Lengthening System

This prospective, observational clinical study intends to actively collect clinical data related to the use of the FITBONE Transport and Lengthening System in a representative number of users and patients, observed in the short (\<1yr) and medium (approximately 1 and 2 years) term after implantation of the device. Co-Primary Endpoints: Primary Safety Endpoint: Percentage of unplanned reoperation and/or revision surgery. Instances of re-operation and/or revision as categorized as "planned" or "unplanned" by the surgeon. Primary Performance Endpoint: Percentage of achievement of planned length. Length of the planned transport (and lengthening when applicable) vs the actual overall length of the segment at the time of nail extraction. Secondary Endpoints: * Bone Healing: Radiographic evidence of healing of 3 out of 4 cortices * Consolidation Index: Time to achieve bone healing (days)/ achieved length (cm) * Distraction Index: Time of distraction (days)/ achieved length (cm) * Nail Reliability: Ratio between the number of successfully completed lengthening treatments and the number of implanted lengthening devices * Nail Accuracy: Ratio between the achieved length and the planned length * Time to achieve transport and lengthening * Loss of Range of Motion at full consolidation: degrees from baseline * Nail Extraction complications/failures * Patient-reported outcome measures * Mobility measures * Adverse events Safety Endpoint: The percentage of cases in which unplanned reoperations and/or revision surgery occurred.