Published online Jan 18, 2022. doi: 10.5312/wjo.v13.i1.112
Peer-review started: March 29, 2021
First decision: October 17, 2021
Revised: October 26, 2021
Accepted: December 21, 2021
Article in press: December 21, 2021
Published online: January 18, 2022
Processing time: 293 Days and 20.7 Hours
Four-corner fusion (4CF) is a motion sparing salvage procedure that is used to treat osteoarthritis secondary to advanced collapse or longstanding scaphoid nonunion advanced collapse. Proximal row carpectomy and 4CF are the two mainly used surgical techniques in such cases. The decision to choose one technique over the other is primarily based on the surgeon’s preference and experience, as long-term results are not clearly elucidated in the current literature so far.
The long-term survivorship and ultimate conversion rate of 4CF to wrist arthrodesis remains poorly described. As various fixation techniques have been employed (Kirschner wires, headless compression screws, staples, plates), different potential complications have been observed, in particular, nonunion, progressive osteoarthritis or hardware impingement/irritation. There is no consensus on the best surgical implant and no synthesis on the long-term outcomes.
To provide a systematic approach on evaluating evidence reporting on the long-term outcomes of 4CF with appropriate tools for critical appraisal. We aimed to compare patient-reported outcomes, fusion rates, grip strength, range of motion and rates of development of radiocarpal osteoarthritis and revision to total wrist fusion.
A study protocol for the systematic search was registered prospectively in the international prospective register (PROSPERO) and performed according to the PRISMA guidelines. Data collection included fusion rates, revision rates and conversion rates to total wrist arthrodesis. Wrist range of motion, including wrist flexion and extension, total flexion-extension arc, as well as radial-ulnar deviation, was extracted. Grip strength was noted as percentage of the opposite hand. Patient-reported outcome measures were included as the Disabilities of the Arm, Shoulder, and Hand questionnaire and the visual analog scale scores (Table 4). Where available, data regarding incidence of radiolunate arthritis was included. The quality of all the studies were then assessed using the Methodological Index for Non-Randomized Studies criteria.
A total of 11 studies including 436 wrists with a mean follow-up of 11 ± 4 years (range: 6-18 years) was included. Quality assessment according to Methodological Index for Non-Randomized Studies criteria tool averaged 69% ± 11% (range: 50%-87%). Fusion rate could be extracted from 9/11 studies and averaged 91%. Patient-reported outcomes were extracted at last follow-up from 8 studies with an average visual analog score of 1 ± 1 (range: 0-2) and across 9 studies with an average Disabilities of the Arm, Shoulder, and Hand score of 21 ± 8 (range: 8-37). The postoperative grip strength was noted in 8 studies and averaged 68% ± 18% of the contralateral side. Total postoperative flexion-extension arc was on average 66 ± 9. At last follow-up, the cumulative conversion rate to total wrist fusion averaged 6%.
The 4CF of the wrist is a reliable surgical technique, capable of achieving a good long-term patient satisfaction and survivorship with low rates of conversion to total wrist fusion.
Future studies should define their study populations and protocols a priori before analysis. More in-depth details regarding patient selection (mostly preoperative data on range of motion, grip strength and radiolunate osteoarthritis) should be provided that would allow objective comparison.