Functional and Radiographic Outcomes of the Sauvé-Kapandji and Darrach Procedures in Rheumatoid Arthritis

Abstract

Background Deterioration of the distal radioulnar joint (DRUJ) in rheumatoid arthritis (RA) manifests as pain, weakness, and reduced range of motion. The Darrach and Sauvé-Kapandji (S-K) procedures are used when medical management fails to control these symptoms. However, there is a paucity of literature comparing the outcomes of these procedures. The purpose of this study is to compare the clinical and radiographic outcomes of the Darrach and S-K procedures in RA patients.

Materials and Methods This is a retrospective, single institution cohort study of RA patients who underwent the Darrach or S-K procedure between 2008 and 2016. Ulnar translation, range of motion, and functional improvement were compared.

Results Nine patients (13 wrists) underwent the Darrach procedure, and nine patients (11 wrists) underwent the S-K procedure. The average length of follow-up was 1.3 years. Pain, function, and range of motion improved in both groups. The degree of ulnar translation did not significantly change after either procedure.

Conclusion Given their similar outcomes, we found no evidence that the S-K procedure is superior to the Darrach procedure or vice versa. However, when surgery is indicated for younger RA patients with DRUJ disease and ulnar translation, the S-K may be better suited to prevent radiocarpal joint dislocation.

Introduction

Rheumatoid arthritis (RA) commonly affects the wrist, particularly the distal radioulnar joint (DRUJ). 1 Patients with caput ulnae syndrome have changes in the DRUJ due to RA, with dorsally prominent ulna head due to volar displacement of the sigmoid fossa of the radius relative to the ulna head. Symptoms include pain, weakness, and limited range of motion, particularly in rotation. 2 When these symptoms persist despite optimal medical management and splinting, surgical intervention is warranted, preferably before there are tendon ruptures. Two main surgeries, the Darrach procedure and the Sauvé-Kapandji (S-K) procedure, have been reported to address these issues. 3 4 5

The Darrach procedure involves distal ulnar resection with the osteotomy at the level of the proximal margin of the sigmoid notch. Results have been reported to be worse in patients with increasing lengths of bony resection and in younger, higher demand patients. 6 7 In RA, there is a significant risk of ulnar translation secondary to disease activity and loss of ulnar head support. 8 For this reason, concurrent total wrist fusion as well as various soft tissue stabilization techniques are often considered. The extensor carpi ulnaris (ECU) tendon and/or the flexor carpi ulnaris (FCU) tendon are usually used to suspend and stabilize the ulna shaft. 9 10 The Darrach procedure has been the preferred method in older patients and results in pain relief and full rotation in the majority of patients. 11

The S-K procedure consists of a radioulnar joint arthrodesis and the creation of a pseudoarthrosis proximal to the fusion. Compared with the Darrach procedure, the S-K procedure provides better ulnar support and is believed to reduce the risk of ulnar translation. Previous studies have reported decreased pain and improved range of motion after over 10 years of follow-up. 3 Nakagawa et al recommended the S-K procedure as the treatment of choice for younger, more active patients due to the preservation of ulnar support of the wrist. 4

There is a paucity of literature directly comparing outcomes of these two procedures and a lack of consensus regarding the appropriate indications for a particular procedure. Furthermore, the conclusions of the existing studies are conflicting as to whether one procedure is superior in regards to ulnar translation. 4 5 Current medical management, including the combination of methotrexate with newer biologics, reduces disease activity, improves patients’ function, and slows radiographic progression by decreasing synovial proliferation and joint and soft tissue destruction. 12 No study has compared the outcomes of surgical intervention since the widespread acceptance of these new medical therapies in the early 2000s. The purpose of this study is to compare radiographic and clinical outcomes for Darrach and S-K procedures as well as their functional stability. Secondary aims include evaluating symptom control and the need for additional interventions.

Materials and Methods

Study Design and Subjects

This study was a retrospective review of subjects derived from a prospectively collected database and was approved by our Institutional Review Board. Included patients were seen at our institution and treated within the Department of Plastic and Reconstructive Surgery over a 9-year period (2008–2016). Eligible patients were aged 18 to 100 years at the time of surgery and had a minimum of 3 months of follow-up after the Darrach or S-K procedure. Patients with previous wrist surgery were excluded. All surgeries were performed by the senior author (S.D.L.).

Study Variables

The primary outcome variable in this study was ulnar translation. We used two common measurements of ulnar translation. The first was the Gilula method, which measures the proportion of the lunate that lies ulnar to the radius. Ulnar translation is present when this ‘lunate uncovering’ is more than 50%. 13 This method has been used extensively in the hand surgery literature and has been found to be the most practical and sensitive method to assess for ulnar translation of the carpus. The second measurement used to assess ulnar translation was the ulnocarpal distance (UCD) described by Thirupathi et al 8 The pisiform bone is used as a reference point because it is not commonly affected by RA and is well preserved in advanced disease. To measure the UCD, a line is drawn connecting the ulnar border of the pisiform and the radial styloid. The portion of the line that lies ulnar to the radius is the UCD ( Fig. 1 ). The ulnocarpal distance ratio (UCDR) is calculated by dividing the UCD by the length of the third finger metacarpal. 8 A normal UCDR is 0.27. 14

Fig. 1.

Left: Gilula method. Right: Ulnocarpal distance.

The secondary outcome variables were carpal collapse, range of motion of the wrist, patient reported pain, and functional improvement. Degree of carpal collapse was measured with the carpal height ratio (CHR) described by Youm and Flatt. 15 The distance from the base of the third finger metacarpal to the distal radial articular surface, measured along the projection of the longitudinal axis of the third metacarpal, was divided by the length of the third finger metacarpal. 15 A normal CHR is 0.53. 14 Analog pain scores were collected from the preoperative visit and the latest follow-up appointment. Functional improvement measures included the Modified Health Assessment Questionnaire (mHAQ) and the Clinical Disease Activity Index (CDAI). The mHAQ is a validated measure of RA patients’ ability to perform activities of daily living without difficulty (score 0), with some difficulty (score 1), with much difficulty (score 2), or unable to do (score 3). The mHAQ score is the mean of the scores for eight activities. 16 17 The CDAI is the composite of the swollen joint count, the tender joint count, the patient global assessment of disease activity, and provider global assessment of disease activity with a maximum score of 76. It is strongly correlated with patient-reported pain and is widely used to measure RA disease activity. 18 19 The level of disease activity is interpreted as in remission (CDAI ≤ 2.8), low (2.8 < CDAI ≤ 10), moderate (10 < CDAI ≤ 22), or high (CDAI > 22). 20 The mHAQ and the CDAI scores from the rheumatology appointments that most closely aligned with the hand surgery preoperative and latest postoperative appointments were used. Other variables collected included demographics (age and sex), disease characteristics (years since RA diagnosis, erythrocyte sedimentation rate [ESR], and C-reactive protein [CRP]), medical variables (smoking status, chronic steroid use, and biologic use), postoperative complications or re-operations, tourniquet time, and additional interventions.

For the statistical analysis, Student's paired t -test was used to compare the preoperative to postoperative results within both groups. Independent samples t -test was used to compare the results between the two procedures. The significance level was set at p < 0.05.

Surgical Indications

The most common indication for surgery was caput ulnae deformity, which presented as dorsal prominence of the ulna head with pain, swelling, and loss of range of motion due to destruction of the DRUJ. Some patients had rupture or impending rupture of the extensor tendons. In the Darrach group, eight wrists had tendon rupture at the time of surgery. In the S-K group, three wrists had tendon rupture, and two wrists had impending rupture, which was identified by palpable crepitus of the extensor tendons over the DRUJ with extensor tendon motion. The Darrach procedure was selected for older patients with lower functional demand or extensive destruction of the distal ulnar bone. The S-K procedure was selected for younger, more active patients who presented with marked ulnar translation of the carpus with the goal of preservation of ulnar-sided support of the carpus offered by this procedure. Biologic agents had been held for 4 weeks prior to surgery and were resumed at the first follow-up visit at 1 week after surgery.

Surgical Technique

Darrach procedure: The ulnar head was resected at a 45-degree angle with the ulnar side kept slightly longer than the radial side. The ECU tendon was used to stabilize the distal ulna. A bone tunnel was created on the dorsalulnar aspect of the ulnar shaft. The ECU tendon was split longitudinally. One portion was released proximally at its musculotendinous junction. It was then passed in through the distal ulnar shaft, out through the bone tunnel, and sutured back to itself as well as the remainder of the proximal ECU tendon ( Fig. 2 ).

Fig. 2.

Surgical technique for the Darrach procedure.

S-K procedure: Arthrodesis of the DRUJ was fixated with a headless compression screw. After the arthrodesis of the DRUJ and ulnar neck resection, a pronator quadratus (PQ) interposition was used to both stabilize the proximal stump of the ulna and to inhibit bony regrowth across the pseudoarthrosis. The PQ muscle was released proximally from the volar shaft of the ulna and from the ulnar-sided soft tissue attachments. The PQ was then transferred dorsal to the ulnar shaft and sutured to the dorsal ulnar ulna shaft with suture passed through bone tunnels ( Fig. 3 ).

Fig. 3.

Surgical technique for the Sauvé-Kapandji procedure.

Postoperative Management

In both groups, patients were splinted or casted with the wrist at neutral rotation and 15 degrees extension for 5 to 6 weeks. Metacarpophalangeal (MP) joints were immobilized in extension only for those patients who required extensor tendon reconstruction during surgery. S-K patients were confirmed radiographically and clinically to have united the DRUJ arthrodesis and maintained alignment of the ulna shaft with the radius on posteroanterior (PA) and lateral views. Darrach patients were confirmed to have maintained alignment on PA and lateral views as well. Formal hand therapy and weaning of the splint were commenced at this point and took an average of 6 weeks. At 12 weeks after surgery, patients were released to do unrestricted activity.

Results

Eighteen RA patients and 24 wrists were included in this study. Nine patients and 13 wrists received the Darrach procedure. Nine patients and 11 wrists received the S-K procedure. Patients in the S-K group were significantly younger than patients in the Darrach group ( p < 0.05) ( Table 1 ).

Table 1. Patient demographics and disease characteristics.

	Darrach group	Sauvé-Kapandji group
Abbreviations: CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; RA, rheumatoid arthritis; SD, standard deviation. a Significant difference between groups ( p < 0.05).
Subjects (number wrists)	9 (13)	9 (11)
Sex—percent female	66.7%	88.9%
Age at operation (SD)	59 (10.9) a	47 (14.7) a
Duration of RA at operation in years (SD)	18.7 (10.2)	10.8 (11.0)
ESR (SD)	23.8 (14.8)	20.3 (13.9)
CRP (SD)	1.53 (2.71)	1.72 (2.46)
Current smokers (%)	22.2	11.1
Chronic steroid use (%)	22.2	44.4
Biologic use (%)	44.4	77.8
Tourniquet time in minutes (SD)	85.3 (36.5)	94.4 (31.0)

In the Darrach group, 6 (46.2%) of the 13 wrists required additional procedures, including MP and proximal interphalangeal (PIP) joint implant arthroplasty, extensor tendon centralization, and correction of swan-neck deformity. Additionally, one patient (two wrists) required total wrist arthrodesis at the time of the Darrach procedure. In the S-K group, no patients required additional procedures related to RA.

Symptoms and Complications

In the Darrach group, 9 (69.2%) of the 13 wrists reported no pain. Four (30.8%) of the 13 wrists reported minimal pain, but only 1 was managed on narcotic analgesics for pain in multiple joints including the wrist and was on the same medication dose as prior to her wrist surgery. Analog pain scores (0–10) improved from an average of 6 (range 1–10) to 1 (range 0–3) at the latest postoperative visit ( p < 0.01). There were no postoperative complications in the Darrach group. In the S-K group, 8 (72.7%) of the 11 wrists reported no pain. Three (27.3%) of the 11 wrists reported minimal pain with 1 managed on narcotic analgesics for joint pain, including the wrist and was on the same medication dose as prior to surgery. Analog pain scores improved from an average of 6 (range 1–8) to 1 (range 0–2) at the latest postoperative visit ( p < 0.01). All DRUJ arthrodesis in the S-K group achieved union. There were no postoperative complications in the S-K group.

Functional Improvement

In the Darrach group, the mHAQ scores remained statistically unchanged from an average of 0.430 (range 0–1.75) preoperatively to 0.315 (range 0–1.13) postoperatively ( p = 0.35). The CDAI scores did not change significantly from a preoperative average of 9.0 (range 1.0–19) to a postoperative average of 7.9 (range 1.0–20.0) ( p = 0.48). The subcomponent of patient global assessment of disease (range 0 to 10) improved from 7 (range 6–10) to 4 (range 0–9) ( p < 0.01).

In the S-K group, the mHAQ scores improved from an average of 0.931 (range 0–2.70) to 0.397 (range 0–1.00), but this difference did not reach statistical significance ( p = 0.08). The CDAI scores also trended toward improvement from an average of 18.4 (range 6.0–65) to 6.7 (range 1.0–13) but did not reach statistical significance ( p = 0.17). However, the subcomponent of patient global assessment of disease improved from 4 (range 1–9) to 2 (range 1–6) ( p = 0.02) ( Table 2 ). There were no significant differences between groups in any of the preoperative or postoperative scores.

Table 2. Functional and disease activity measures.

		Darrach group mean ± SD	Sauvé-Kapandji group mean ± SD
Abbreviations: CDAI, Clinical Disease Activity Index; mHAQ, Modified Health Assessment Questionnaire; SD, standard deviation. a Significantly different from preoperative value ( p < 0.05).
Pain	Preoperative	6 ± 3	6 ± 2
	Postoperative	1 ± 2 a	1 ± 1 a
mHAQ	Preoperative	0.430 ± 0.661	0.931 ± 1.03
	Postoperative	0.315 ± 0.506	0.397 ± 0.490
CDAI	Preoperative	9.0 ± 7.1	18.4 ± 19.2
	Postoperative	7.9 ± 8.6	6.7 ± 4.3
Patient assessment of disease severity	Preoperative	7 ± 3	4 ± 2
	Postoperative	4 ± 4 a	2 ± 2 a

Range of Motion

Range of motion measurements from the preoperative visit and the latest follow-up were compared. There was a trend toward decreased wrist flexion postoperatively in the S-K group ( p = 0.06). Mean wrist extension did not significantly differ between pre- and postoperative measurements in either group. In both groups, pronation significantly improved after surgery ( p < 0.05) ( Table 2 ). Supination improved after the Darrach procedure and was also much lower than in the S-K group prior to surgery ( p < 0.05) ( Table 3 ).

Table 3. Range of motion in the Darrach and Sauvé-Kapandji groups.

		Darrach group mean ± SD	Sauvé-Kapandji group mean ± SD
Abbreviation: SD, standard deviation. a Significantly different from preoperative value ( p < 0.05).
Wrist flexion (°)	Preoperative	36 ± 29	39 ± 16
	Postoperative	33 ± 22	24 ± 18
Wrist extension (°)	Preoperative	25 ± 22	29 ± 19
	Postoperative	27 ± 15	35 ± 17
Supination (°)	Preoperative	31 ± 17	58 ± 23
	Postoperative	63 ± 22 a	62 ± 29
Pronation (°)	Preoperative	72 ± 4	70 ± 12
	Postoperative	82 ± 9 a	83 ± 5 a

Radiographic Evaluation: Ulnar Translation and Carpal Collapse

Posteroanterior radiographs from the preoperative visit and the latest follow-up were used for measurements. One patient (two wrists) with total wrist arthrodesis was excluded from analysis of ulnar translation. In both groups, there was no significant change in ulnar translation as measured by both the quantitative Gilula method and the UCDR ( Table 4 ). There was no change in carpal collapse in either group as measured by the CHR ( Table 5 ). Representative radiographs from each group are shown in ( Fig. 4 5 ).

Table 4. Ulnar translation of the carpus in the Darrach and Sauvé-Kapandji groups as measured by the Gilula method and ulnocarpal distance ratio.

		Darrach group mean ± SD	Sauvé-Kapandji group mean ± SD
Abbreviation: SD, standard deviation.
Gilula method	Preoperative	0.42 ± 0.068	0.51 ± 0.14
Normal: < 0.50	Postoperative	0.38 ± 0.095	0.43 ± 0.14
Ulnocarpal distance ratio	Preoperative	0.28 ± 0.057	0.33 ± 0.065
Normal: 0.27	Postoperative	0.30 ± 0.042	0.30 ± 0.067

Table 5. Carpal collapse in the Darrach and Sauvé-Kapandji groups as measured by the carpal height ratio.

		Darrach Group mean ± SD	Sauvé-Kapandji group mean ± SD
Abbreviation: SD, standard deviation.
Carpal height ratio	Preoperative	0.41 ± 0.14	0.46 ± 0.076
Normal: 0.53	Postoperative	0.41 ± 0.11	0.44 ± 0.071

Fig. 4.

Pre- and postoperative images of a 70-year-old woman who underwent the Darrach procedure.

Fig. 5.

Pre- and postoperative images of a 47-year-old woman who underwent the Sauvé-Kapandji procedure.

Intergroup Comparison

There was a trend toward greater preoperative ulnar translation in the S-K group according to both the quantitative Gilula method ( p = 0.07) and the UCDR ( p = 0.07). There were no differences in postoperative ulnar translation. There were also no differences in pre- or postoperative range of motion except for a trend toward better preoperative supination in the S-K group ( p = 0.06).

Discussion

The Darrach procedure and the S-K procedure have both been shown to have satisfactory results in terms of pain reduction and improved symptoms in RA patients. The S-K procedure has been traditionally selected to prevent postoperative ulnar translation, which was a potential consequence of the Darrach procedure. However, evidence supporting this indication has been mixed. Nakagawa et al showed that the S-K procedure resulted in a lower incidence of postoperative ulnar migration and radial rotation compared with the Darrach procedure. 4 However, Kobayashi et al concluded that there were no significant differences between the S-K procedure and the Darrach procedure in terms of carpal changes after 4 years of follow-up. 5 Since both procedures resulted in ulnar translation of the carpus, they concluded that the Darrach procedure was not inferior to the S-K procedure.

In the present study, we found no significant differences in the degree of ulnar translation after either the Darrach or S-K procedures using both the quantitative Gilula method and the UCDR. However, there was a trend toward greater preoperative ulnar translation in the S-K group. The S-K procedure may prevent the late consequences of ulnar translation such as radiocarpal joint dislocation by maintaining a wider radiocarpal shelf. It has previously been shown that by narrowing the shelf, the Darrach procedure can lead to dislocation of this joint in the ulnar direction. 4 Therefore, in younger, more active patients who are at risk for dislocation due to preoperative ulnar translation, and may have a longer expected lifespan after the procedure in which this problem might occur, the S-K is our preferred procedure. Additionally, given that the Gilula method and UCDR demonstrated similar results, both measurements appear to be valid measurements of ulnar translation.

One reason that we might not have detected differences in ulnar translation post-operatively is that our patients were medically optimized. Fifteen of the 18 patients were on a combination of steroids, methotrexate, leflunomide, and hydroxychloroquine. Additionally, 11 of the 18 patients were on biologic agents, most often adalimumab or etanercept, before being evaluated for surgery, all of whom resumed these agents after surgery. These biologics could have halted further joint destruction in the wrist and prevented the ulnar migration that was observed in the comparative studies that had been conducted before these medications were standard treatments. A more recent long-term follow-up study of patients who underwent the Darrach procedure for post-traumatic DRUJ arthritis showed that only 7.1% of patients had any radiographic evidence of radioulnar impingement, which inevitably leads to ulnar translation when lifting is performed with the forearm in neutral rotation. 21 In an era of advanced medical management with an array of immunosuppressive and anti-cytokine agents, the choice of which surgery to do may be less critical in terms of preventing radiographic progression of disease. However, in the subset of younger patients who present with ulnar translation, it may still be advantageous to perform with S-K procedure to prevent radiocarpal joint dislocation by leaving a wider radioulnar shelf.

Both groups showed functional improvement as measured by the patient assessment of disease activity. It has previously been shown that when considering the global assessment of disease, patients place the most emphasis on their overall well-being and quality of life, whereas providers are more likely to consider objective data. 22 23 In terms of patients’ ability to perform activities of daily living, only the S-K group showed improvement in the mHAQ. Neither group had significant changes in the CDAI. Given that the patient assessment of disease activity improved, the lack of improvement in the CDAI is likely due to the swollen and tender joint count not changing substantially. While the Darrach and S-K procedures improve pain in the DRUJ, other joints would not have been affected. Furthermore, given the older age of patients in the Darrach group and their longer course of RA, these patients may be less likely to achieve zero disability regardless of surgery, which is a possible explanation as to why there was no significant improvement in their mHAQ.

Improvements in range of motion did not substantially differ between groups. While one of the most recent head-to-head studies showed worsening of flexion and extension postoperatively, 4 in our current study, there was only a trend toward decreased flexion in the S-K group, but no significant change in total arc of motion (flexion + extension) after either procedure. However, pronation significantly improved in both groups and supination improved in the Darrach group. Of note, the Darrach group had worse supination preoperatively while the S-K group maintained a higher degree of supination both prior to and after surgery. Allowing patients greater range of motion likely contributed to improved function and ability to perform activities of daily living observed to some degree in all patients postoperatively. Improvement in pain was statistically significant in both groups, with all patients reporting either minimal or no pain at the latest follow-up. These results indicating similar outcomes support our conclusion that both the Darrach and the S-K procedure should be considered for patients with advanced and symptomatic RA, with the choice of surgery based on surgeon experience and patient preference. At our institution, we choose the S-K procedure for younger, more active patients with preoperative ulnar translation to prevent the possibility of radiocarpal joint dislocations.

Only patients in the Darrach group required additional hand and wrist procedures after surgery. One possible explanation could be that the Darrach group had more advanced disease. Although the acute phase reactant CRP only accounts for 15 to 19% of the total variance of joint destruction, it is nevertheless a routine marker for disease severity. 24 Even after 10 years of disease, CRP has been shown to be an independent marker of the severity of hand joint damage. 25 Since there was no significant difference in acute phase reactants at the time of surgery on the patients reported in our study, disease severity is not a likely explanation for why the Darrach group received more additional surgeries nor is it associated with which procedure patients received. However, the Darrach group was older at the time of surgery and trended toward having a longer duration of disease (18.7 vs 10.8 years, p = 0.08), which likely contributed to this group requiring additional hand and wrist procedures after the initial operation. Longer disease duration is known to be associated with worse joint destruction in the hand. 26 Thus, patients who are advised to receive the Darrach procedure, particularly those with long-standing disease, should be counseled that additional operations, most notably MP and PIP joint procedures, are often indicated.

There are several limitations to the current study. First, this is a retrospective study with a relatively small sample size, and it is therefore difficult to determine whether there are other unmeasured factors that influenced the selection of a surgical procedure or its outcomes. However, Alderman and Chung showed that rheumatologists may view rheumatoid hand surgery, including procedures to reconstruct the DRUJ, as significantly less effective than do hand surgeons. 27 These different attitudes regarding the benefits of surgical management, along with the widespread use of newer medications, make cohorts of the size of our study typical for current practice. In addition, our follow-up time was on average 1.3 years. It is possible that not enough time had passed to show progression of or improvement in ulnar translation at the latest follow-up. However, this study establishes that in this era of newly advanced medical management for RA, both procedures equally improve patients’ symptoms and stop the progression of radiographic findings at least temporarily.