Precision of the Wilson corrective osteotomy of the first metacarpal base using specific planning and instruments for treatment of basal thumb arthritis

Abstract

Introduction Arthritis of the basal thumb is a relatively common condition also affecting younger patients. Wilson et al. described a 20°–30° closing wedge osteotomy of the first metacarpal bone to unload the trapeziometacarpal joint. It was the purpose of this study to analyze the clinical and radiographic outcome of patients who underwent proximal extension osteotomy of the first metacarpal bone using patient-specific planning and instruments (PSI). Methods All patients who underwent proximal metacarpal osteotomy for basal thumb arthritis at our tertiary referral center were retrospectively included. The patients underwent preoperative planning using computed tomography and 3D segmentation to build patient-specific guides and instruments for the operative treatment. Stable fixation of the osteotomy was achieved by internal plating. The inclusion criterion was a minimum follow-up of 1 year with clinical examination, including the Michigan Hand Outcomes Questionnaire (MHQ), and computed tomography to validate the correction. Complications and reinterventions were recorded. Results A total of eight Wilson osteotomies in six patients could be included at a mean follow-up duration of 33±16 months (range, 12 to 55 months). The patients were 49±8 years (range, 36 to 58 years) at the surgery and 88% were female. The postoperative MHQ for general hand function was 77±8 (range, 45 to 100) and the MHQ for satisfaction was 77±28 (range, 17 to 100). The working status was unchanged in 7/8 hands (6/7 patients). Radiographic analysis revealed successful correction in all cases with unchanged Eaton–Littler stage in 7/8 hands. No complications were recorded. Conclusion The combined extending and ulnar adducting osteotomy using patient-specific guides and instrumentation provides an accurate treatment for early-stage thumb arthritis. Level of evidence Type IV—retrospective, therapeutic study.

Basal osteotomy of the first metacarpal using patient-specific guides and instrumentation: biomechanical and 3D CT-based analysis

“…We evaluated radiographic outcomes after extension osteotomy of the MC1 in TMC OA and created 3D representations of distance fields using a CT-based method to evaluate variations in the peak load zones of the joint space in vivo. Based on a previously conducted study verifying the precision of osteotomy using PSI [ 10 ], our results of radiological analysis of the displacement of the peak loading zone on the articular surfaces did not allow a conclusive explanation for our assumption of a dorsal–radial displacement after osteotomy due to the heterogeneous and small values below 1 mm in the majority of patients. Nevertheless, interesting trends emerged that could contribute to a flatter pressure distribution and a dorsal shift of the peak stress zone.…”

“…1 ). A previously published study at the same institution, which applied the same procedures and was able to corroborate their precision, explains the more precise approach to creating these PSIs and outlines the same surgical procedure [ 10 ].

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“…Depicted is an osteotomy wedge (red) with 20° dorsalextending and 5° ulnar adducting osteotomy. To perform the planned osteotomy and to position the Kirschner wires, the patient-specific guides and instruments (blue) were used [ 10 ] …”

“…New innovations in 3D printing technology have facilitated the production of patient-specific guides that enable the transfer of computer-assisted planning to the intraoperative field. Regarding TMC OA, only one study analysed the surgical outcome in terms of the precision of the corrective osteotomy, performed with PSI, using postoperative CT data [ 10 ]. In their retrospective study, a 20° extending and 5° ulnar adducting osteotomy was performed after a 3D analysis of the TMC joint to achieve an optimal pinch-grip position and articular surface contact.…”

Computer-assisted planning vs. conventional surgery for the correction of symptomatic mid-shaft clavicular nonunion and malunion

“…For the pre to postoperative analysis of osteotomies, the method can be used to represent the deviation in height/length and rotation of the lateral bone part of the OT between the planned and the performed surgery. 7 An analysis using oriented distances and angles in a standard clavicle coordinate system was also performed. 26 For this purpose, the medial third of the postoperative clavicle was projected onto the contralateral side or planning.…”