Clinical Outcomes of TTA Using the TTARapidTINY System in Toy-Sized Dogs with Cranial Cruciate Ligament Disease with or without Medial Patellar Luxation

Abstract

Objective

This study aimed to conduct a retrospective study investigating clinical outcomes of tibial tuberosity advancement (TTA) using the TTARapidTINY system for cranial cruciate ligament rupture (CrCLR) in toy-sized dogs (≤7.0 kg) with and without concurrent medial patellar luxation (MPL), respectively.

Methods

Medical records of toy-sized dogs that underwent TTA using the TTARapidTINY system were reviewed. Dogs were divided into two groups: Those with CrCLR only (CrCLR group) and those with concurrent MPL (CrCLR + MPL group). The data, including signalment, intraoperative findings, perioperative complications, postoperative patellar tendon angle, lameness scores (both preoperatively and at 12 weeks postoperatively) and owner surveys, were retrieved and compared between the two groups.

Results

A total of 52 affected stifle joints from 46 dogs were identified (CrCLR group: 12 stifles, CrCLR + MPL group: 40 stifles). The occurrence of major complications (2/12 [16.6%] vs. 2/40 [5%]), the percentage of a zero lameness score at 12 weeks postoperatively (11/12 [91%] vs. 40/40 [100%]), and overall owner satisfaction were statistically not different. However, the postoperative patellar tendon angle significantly differed between the CrCLR group (95.1 ± 6.0 degrees) and the CrCLR + MPL group (90.8 ± 4.0 degrees). In the CrCLR + MPL group, MPL recurred in one case (2.5%).

Clinical Significance

In our cohort of 46 toy-sized dogs, the TTARapidTINY system proved to be a safe and effective surgical tool, resulting in satisfactory functional outcomes in dogs with both CrCLR alone or combined with MPL.

Keywords

cranial cruciate ligament rupture - TTARapidTINY - dog - tibial tuberosity advancement - medial patellar luxation

Authors' Contributions

T.F. performed the surgeries in all cases, collected and analysed the data and drafted the manuscript. T.M. interpreted the data, revised the draft and translated the manuscript. Both authors contributed substantially to the conception of the study and agreed to be accountable for all aspects of the research.

Publication History

Received: 08 November 2024

Accepted: 09 August 2025

Article published online:
25 August 2025

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