The mid-term outcome after reconstruction the DRUJ with rib perichondrium is promising and the results seem to be consistent over time.
It is hard to find reliable surgical solutions to reconstruct painful osteoarthritic DRUJs in young non-rheumatoid patients. In the long-term, complications tend to occur which may cause hesitation to intervene surgically in these patients. Partial or total resection of the ulnar head are reasonable treatment options in the elderly patients with rheumatoid changes, but hardly for young non-rheumatoid patients. The Darrach procedure is hampered with problems as instability and painful impingement of the remaining ulnar stump towards the radius (1). In a recent patient-reported-outcome study by Eberlin, complication and reoperation rates after the Darrach procedure (n=57) and the Sauve Kapandji procedure (n=28) were studied. The complication rate was reported to be 30 % and 50 % respectively, while the reoperation rate was 18 % and 36 % respectively. Overall, 52 patients (61 %) in this study completed a PROS, and the authors did not find any significant difference in pain and satisfaction rate in between the two groups (2). In a recent long-term follow-up study of the Sauve-Kapandji procedure, Nagy et al found a high incidence of revision surgery due to instability to the proximal ulnar stump and recommended a restriction of this method to only very selected cases (5). If the surrounding soft tissue is sufficient, the clinical outcome has been reported to be reasonably good after the Bowers procedure in both rheumatoid and none-rheumatoid patients by several authors (3, 21–23). The method is considered as a salvage procedure (21, 24) and the main ambition with this technique, as described by Bowers in 1985, is to reduce pain and to improve the ROM in the DRUJ, not to stabilize the joint (25). In this context the method is suitable for the rheumatoid patients, as these patients usually have lower physical demands in comparison to the non-rheumatoid patients. Several modifications of the procedure has been reported, as interposing a tendon or a flap of the extensor retinaculum into the joint, or dorsalisation of the extensor carpi ulnaris, in efforts to increase stability to the ulnar stump and achieve better results also in the non-rheumatoid patient(22, 26–28). A relatively high DASH score (31 and 35 respectively) has been reported in combination with a good patient reported outcome measure (PROM) after the Bowers procedure (3, 21). In a recent report by Nawijn, the relatively high DASH score in relation to low pain and high satisfaction rate might be attributed to the fact that the DASH score reflects not only the DRUJ problem but also general problems in the wrist caused by inflammatory arthritis or posttraumatic sequelae (3).
The salvage options after a failure, following a Darrach or Sauve Kapandji procedure, is mainly limited to implant surgery of some kind. In general, the results after implant surgery to the DRUJ has improved during the last decade. However, implants often fail to achieve function suitable for heavy load in the long term. Restricted range-of-motion, persistent pain and implant loosening are common problems(6, 7, 10).
The surgical method to resurface the DRUJ with rib perichondrium was reported in 2014 along with the short-term results of the first two patients in the present cohort (11). The gratifying outcome in these patients have persisted over time, and actually improved in case 2, resulting in an almost normal function in the reconstructed joints. The follow-up time for the two additional patients is shorter but the results are similar, especially in the fourth case. The third case still has problems with pain and restricted ROM but the results have clearly improved in comparison to the preoperative findings. The preoperative problems in the third case differed somewhat in comparison to the others as the main problem was an impaired ROM. The results in the additional PROS (by letter) showed persistence in the outcome with an unchanged ROM and grip-strength in all cases, and only a slight increase in pain (VAS) in two cases (from 0 to 1 in the 1st case, and from 0 to 3 in the 4th case). The changes in DASH-score, with a decrease in half and an increase in the other half of the study group, is difficult to interpret as the DASH-score might be influenced by many things (e.g. other problems with the arm/hand). In a recent paper, the long-term outcome (mean 37 years) after perichondrium transplantation to the metacarpophalangeal (MCP) joint and the proximal interphalangeal (PIP) joint was presented (17). Three early failures were reported, while the remaining eleven patients in the study-cohort had no additional surgery after the joint reconstruction almost four decades earlier. The authors suggested that function of the resurfaced joints will remain favorable in the long-term in most patients with favorable short-term outcome.
There is often a contrast in between the clinical outcome and the radiological appearance after a perichondrium transplantation (11, 17, 29). In analogy with previous reports, we found radiological signs of bone resorption and remodeling over time in all four cases (Fig. 1-4). The reconstructed joint will not look normal on radiographs. The gap between the sigmoid notch and the ulnar head will be wider. This may be explained by hypertrophy and thickening of the grafts, filling the gap in the joint. In a recent rat study, rib perichondrium was transplanted to cover a localized full-thickness articular cartilage defect created in the rat knee. A relatively high proliferation rate was found early after the transplantation followed by a later increase in cell size (12). The grafts produced hyaline cartilage that filled out the defects and subsequently differentiated to achieve a chondrocyte marker expression pattern and structure similar to the surrounding articular cartilage (12).
Limitations and Strength
It is a clear limitation that the study group only consisted of four patients. The retrospective study design, and the lack of a comparative study group representing another surgical method (e.g. implant surgery or the Bowers hemi-resection procedure), makes it hard to draw any definite conclusions. The mean age in the present study is relatively young (40.5 years) in comparison to most studies about surgery towards osteoarthritis in the DRUJ. Moreover, all four were non-rheumatoid patients. A longer follow-up time for the clinical assessment (mean 3.1 years) would have strengthen the study. The additional survey sent by letter was an effort to overcome this drawback during the ongoing COVID-19 pandemic. In addition, if the pattern of the findings in the recent long-term follow up after perichondrium transplantation to the MCP and the PIP joints (17) is a consistent feature, most failures probably appear at an early postoperative stage. A larger study-cohort and longer follow-up time is needed to conclude if this surgical technique is superior to the more traditional methods or not. A prospective randomized study comparing perichondrium transplantation with implant surgery, or the Bowers procedure would have been helpful but is most likely not feasible due to ethical matters, related to the second surgical site at the ribcage.