Scaphotrapeziotrapezoid Arthrodesis: Systematic Review

[Osteoarthritis of the wrist]

The term osteoarthritis (OA) of the wrist can be used as an umbrella term for various, often independent areas of OA, as the wrist is made up of several joints. Radiocarpal OA often occurs after untreated ligament injuries, incorrectly healed bone fractures in the carpus or after radius fractures involving the joint. A typical sequence of propagation is known for radiocarpal OA following scapholunate (SL) insufficiency or scaphoid pseudarthrosis. Other causes include inflammation, crystal deposits or bone necrosis. Ulnocarpal arthrosis occurs posttraumatically or primarily when there are differences in levels between the ulna and radius. When treating wrist arthrosis, after conservative measures have been exhausted a surgical procedure should be chosen that enables the best possible load-bearing and residual mobility, considering the surgical risks and individual requirements. During salvage operations, the defective cartilage areas are either fused directly or eliminated using appropriate diverting partial fusions and resection arthroplasty. An accurate analysis of the affected zones is crucial for selecting an appropriate intervention.

Biomechanical evaluation of the wrist after scaphotrapeziotrapezoid arthrodesis

BACKGROUND

The main objective of the present study was to present the biomechanical properties of the wrist in patients who underwent scaphotrapeziotrapezoid arthrodesis when compared to a healthy control hand.

METHODS

The study group consisted of 29 consecutive patients who underwent a scaphotrapeziotrapezoid wrist arthrodesis at least 1 year before the research onset. Both hands of all patients were examined in 4 main categories.

RESULTS

Average score obtained in the VAS, before the surgery, without motion of the wrist was 5.21 (SD = 3.04), whereas with wrist motion, it was 8.10 (SD = 1.37). Nineteen (65.52%) patients exhibited weakened wrist muscle strength. After the surgery, only 5 (17.24%) patients declared pain in the wrist. Furthermore, the results obtained in the VAS statistically significant differed from the ones before (p < 0.05). Twenty-eight (96.55%) patients were able to resume their profession. Twenty-seven (93.10%) patients stated that they would opt for the operation again. The peak torque during the analysis of extension of the wrist in the isometric protocol was found to be 8.1 Nm (SD = 2.9), 7.9 Nm (SD = 2.3), and 7.9 Nm (SD = 2.5) in the operated hands and 10.9 Nm (SD = 3.2), 9.6 Nm (SD = 2.9), and 9.1 Nm (SD = 3.8) in non-operated hand for 30° extension, no-flexion, and 30° flexion positions, respectively (p < 0.05).

CONCLUSION

The current study is the first to present the biomechanical parameters of flexor and extensor muscles of the wrist and fingers in patients after the said procedure. Biomechanical assessments with additional isometric, isotonic, and isokinetic tests provide an opportunity to objectify treatment outcomes and guide appropriate rehabilitation by monitoring its effects.

LEVEL OF EVIDENCE

III.

Retrospective analysis of scaphoid trapezium pyrocarbon implant intervention in STT arthritis: a 3-year follow-up study

AIM

The purpose of this study was to evaluate clinical, patient rated and radiological outcome of the scaphoid trapezium pyrocarbon implant (STPI) at a minimum of three years follow-up.

METHODS

Consecutive patients operated with the STPI due to scaphotrapeziotrapezoidal (STT) arthritis between 2012 and 2019 were included. Patients were evaluated preoperatively and annually after surgery for range of motion, grip strength, key pinch, quick-DASH, pain, and satisfaction. Radiographs were evaluated for implant position, signs of dorsal intercalated segment instability (DISI), capitolunate (CL) angle, scapholunate (SL) distance, and presence of osteophytes.

RESULTS

Twenty-six patients (29 implants) were included. Seven implants were revised during the follow up, mainly due to pain: three implants were removed, four patients received a new STPI of a different size, leaving 22 implants in 20 patients available for follow up, 9 males and 11 females. Median age was 61.7 years (51-78 years). Median follow-up time was 68 months (37-105 months). Comparing preoperative status to the last follow-up, wrist extension and deviation, thumb abduction, and grip strength did not change. Key Pinch, quick DASH, pain, and patient satisfaction improved significantly at last follow-up. Radiographic signs of DISI were seen in six cases preoperatively and in 12 cases at last follow-up.

CONLUSION

At a minimum of three years follow-up, the STPI used for STT-arthritis improve pain, quick-DASH result, and patient satisfaction significantly. ROM and grip strength did not change compared to preoperative values. Radiographic signs of carpal instability were common at the follow-up and the revision rate was high.

Arthroscopic Scaphotrapeziotrapezoid Joint Fusion for Osteoarthritis

Background: Arthroscopic scaphotrapeziotrapezoid (STT) fusion (ASTTF) has emerged in the recent decade as an option for traditional open surgery. This retrospective study describes our technique and results of ASTTF. Methods: Medical records and radiological data of patient who had undergone ASTTF between 2014 and 2022 in two tertiary hospitals were reviewed. Results: Five ASTTF in four patients were identified. The mean age of the patients were 52.4 years. Fusion was achieved in four out of five wrists (80%). The mean postoperative radio-scaphoid angle was 48°, grip 32 kg (70% compared to contralateral hand), extension 54° (86%) and flexion 46° (93%). The mean follow-up time was 18 months (range 5 months to 4 years). One wrist (20%) developed STT non-union requiring a reoperation 2 years after index surgery. Conclusions: ASTTF is a technically challenging procedure with a long learning curve and surgery time. However, ASTTF is less invasive compared to the open procedure and our results were like the open procedures described in literature. Further studies are needed to compare the benefits and results of open and ASTTF in a prospective and randomised setup. Level of Evidence: Level IV (Therapeutic).