Scaphotrapeziotrapezoid Arthrodesis Using Limited Wrist Fusion Plates in Kienböck's Disease

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.

Scapho-luno-capitate fusion with proximal lunate articular surface preservation for management of grade IIIA Kienböck's disease: a prospective case series

BACKGROUND

Kienböck's disease is idiopathic lunate avascular necrosis, which may lead to lunate collapse, abnormal carpal motion and wrist arthritis. The current study aimed to assess the outcomes of treating stage IIIA Kienböck's disease by a novel technique of limited carpal fusion via partial lunate excision with preservation of the proximal lunate surface and scapho-luno-capitate (SLC) fusion.

MATERIALS AND METHODS

We conducted a prospective study of patients with grade IIIA Kienböck's disease managed with a novel technique of limited carpal fusion comprising SLC fusion with preservation of the proximal lunate articular cartilage. Autologous iliac crest bone grafting and K-wires fixation were used to enhance the osteosynthesis of the SLC fusion. The minimum follow-up period was 1 year. A visual analog scale (VAS) and the Mayo Wrist Score were utilized for the evaluation of patient residual pain and functional assessment, respectively. A digital Smedley dynamometer was used to measure the grip strength. The modified carpal height ratio (MCHR) was used for monitoring carpal collapse. The radioscaphoid angle, scapholunate angle, and the modified carpal-ulnar distance ratio were used for the assessment of carpal bones alignment and ulnar translocation of carpal bones.

RESULTS

This study included 20 patients with a mean age of 27.9 ± 5.5 years. At the last follow-up, the mean range of flexion/extension range of motion (% of normal side) improved from 52.8 ± 5.4% to 65.7 ± 11.1%, P = 0.002, the mean grip strength (% of normal side) improved from 54.6 ± 11.8% to 88.3 ± 12.4%, P = 0.001, the mean Mayo Wrist Score improved from 41.5 ± 8.2 to 81 ± 9.2, P = 0.002, and the mean VAS score reduced from 6.1 ± 1.6 to 0.6 ± 0.4, P = 0.004. The mean follow-up MCHR improved from 1.46 ± 0.11 to 1.59 ± 0.34, P = 0.112. The mean radioscaphoid angle improved from 63 ± 10º to 49 ± 6º, P = 0.011. The mean scapholunate angle increased from 32 ± 6º to 47 ± 8º, P = 0.004. The mean modified carpal-ulnar distance ratio was preserved and none of the patients developed ulnar translocation of the carpal bones. Radiological union was achieved in all patients.

CONCLUSIONS

Scapho-luno-capitate fusion with partial lunate excision and preservation of the proximal lunate surface is a valuable option for treating stage IIIA Kienböck's disease, with satisfactory outcomes. Level of evidence Level IV. Trial registration Not applicable.

Importance of measurement methods and demographic characteristics in evaluating ulnar variance: A retrospective comparative study

OBJECTIVE

This study aimed to compare 2 methods of ulnar variance (UV) measurement (the perpendicular method and the circular method) and to determine whether UV changed based on the demographic characteristics (sex and age).

METHODS

UV was measured on bilateral wrist radiographs of 124 patients (62 men, 62 women; mean age=48.5 years; range=18-79 years) who had no history of trauma, congenital wrist anomaly, previous wrist surgery, and wrist osteoarthritis by a single radiologist with 4 years of experience. All measurements were made on standardized radiographic images using 2 methods: the perpendicular method and the circular method. All the patients were then divided into groups based on sex and age, and the study population was determined by selecting a similar number of patients for each sex and age group.

RESULTS

The mean UV of the right and left wrists was measured as 0.33 (range=-4.3 to 5.7) mm by the perpendicular method and as 0.034 (range=-5 to 5.7) mm by the circular method. A significant difference was determined between the 2 measurement methods (p<0.001). There was a statistically significant difference between sex and UV values in the left wrist measurements by both methods (p<0.05). A significant correlation was found between the UV and age in both right and left side measurements, indicating a statistically significant difference between the methods (p<0.001).

CONCLUSION

The results of our study demonstrated significant differences in the UV measurement between the 2 methods. Furthermore, UV measurement may change based on age and sex. These differences should be considered in the treatment planning of patients with wrist disorders.

LEVEL OF EVIDENCE

Level IV, Therapeutic Study.