Keywords
Sauvé-Kapandji - arthroscopy - proximal stabilisation
Introduction
The distal radioulnar joint (DRUJ) consists of the sigmoid notch of the radius and
the ulnar head. DRUJ is essential for normal wrist functioning.[1] It presents different curvature radii between its components since the distal radius
has a 15-mm curvature and the ulnar head curvature is only 10-mm. In a neutral pronosupination
position, the contact between facets is 60%, which becomes only 2 or 3 mm in maximum
pronation or supination, i.e., the stability degree is lower.[2] In addition, forearm pronosupination combines rotation and translation movements,
allowing the ulnar head displacement over the sigmoid notch. All these factors result
in DRUJ instability from a bone and biomechanical point of view.[3] DRUJ stabilization fundamentally relies on main stabilizers, such as the triangular
fibrocartilage complex (TFCC), the dorsal and volar radioulnar ligaments, the ulnocarpal
ligaments, the floor of the tendon sheath of the extensor carpi ulnaris (ECU), and
the joint capsule with its volar thickening. Secondary stabilizers include the interosseous
membrane and the deep head of the pronator quadratus muscles.
The diagnosis of DRUJ injuries, whether traumatic or degenerative, is a challenge.
This fact, along with the poor bone stability provided by its incongruent articular
surfaces, leads to early DRUJ osteoarthritis.[4] Traumatic causes include radial fractures consolidated in a bad position[5] and injuries to the primary or secondary stabilizers, while degenerative causes
encompass all chronic arthropathies. All these conditions cause pain in the ulnar
region of the wrist, as well as loss of strength and mobility restriction, affecting
the quality of life of patients.[6]
Several procedures have been proposed to treat this condition when conservative management
fails. These include the Darrach,[7] Bowers,[8] and Sauvé-Kapandji (S-K)[9] procedures, in addition to partial or total joint replacement using a prosthesis.[10] The Darrach procedure is effective for older patients with few functional demands
but leaves an unstable proximal stump and weak grip. The Bowers procedure is out of
use due to tendon interposition-associated complications and its poor outcomes. The
S-K procedure has the advantage of preserving the load since it increases the load-bearing
surface of the radius and carpus and maintains joint stability. Replacement with a
prosthesis significantly improved grip strength, weightlifting strength, range of
motion, and pain, but its complication rate is close to 30%.[11]
The arthroscopic S-K technique, described by Luchetti et al.,[2] is a less invasive procedure with better aesthetic results. Moreover, it preserves
the extensor retinaculum, improving the DRUJ placement in a more anatomical position
and allowing earlier rehabilitation. The S-K procedure consists of a DRUJ arthrodesis
with an ulnar osteotomy, sparing the relationship between the sigmoid fossa of the
radius and the ulnar head. This procedure improves load transmission, mainly in young
people with high functional demands.[12] Arthroscopy allows a complete assessment of the joint status before making decisions;
moreover, it is a less invasive procedure. Our study aimed to describe the surgical
technique of the arthroscopic S-K procedure with proximal tendon stabilization, its
outcomes, complications, and advantages.
Surgical Technique
The arthroscopic S-K technique follows the description from Luchetti et al.[2] and adds tendon stabilization of the proximal stump using the method introduced
by Minami et al.[13]
Standard wrist arthroscopy occurred using a zenith traction tower (Acumed, Hillsboro,
OR, USA), a 2.5-mm arthroscope (Arthrex, Naples, FL, USA), and a 2.9-mm synoviotome
(Smith & Nephew, Andover, MA, USA), beginning with the radiocarpal and DRUJ examination
to complete the diagnosis. The radiocarpal portals included 3-4 and 6R and those for
DRUJ access, such as the dorsal distal radioulnar (d-DRU) and the volar distal radioulnar
(v-DRU),[14] recently described and not used in the technique described by Luchetti et al.[2]
The first step was a complete synovectomy, which allowed good visualization of the
remaining articular cartilage. Articular cartilage resection used 2.9-mm arthroscopy
dissectors and burs ([Fig. 1]) through the RCD-d and v-DRU portals. The arthroscopy was dry but with frequent
washings to remove the cartilage and bone remnants still detached. The cartilage was
removed until the exposure of the subchondral bone of the sigmoid fossa of the radius
and the ulnar head. Subsequently, articular surface reduction and a temporary fixation
with Kirschner wires ([Fig. 2a]) occurred under fluoroscopic control to ensure the correct joint position ([Fig. 2b]) Then, DRUJ fixation used a cannulated screw ([Fig. 3a] and [3b]). his series employed one 4-mm SpeedTip® Cannulated Compression Screw (Medartis®,
Basel, Switzerland) or two 3-mm cannulated screws depending on the size of the ulnar
head. The screws were volar to the extensor retinaculum with the wrist in neutral
pronosupination. In cases with associated ulna plus, arthrodesis compression occurs
after osteotomy to ensure more precise placement of the ulnar head in the sigmoid
fossa and achieve a neutral ulnar variance. With DRUJ arthrodesis completed ([Fig. 4]), an incision is made in the skin of the ulnar edge from the head to the neck of
the ulna, and a 5 to 6 mm osteotomy is performed just proximal to the ulnar head with
chisels or oscillating saw ([Fig. 5a] and [5b]). Complete pronosupination is checked. The surgeon completed the procedure by stabilizing
the proximal stump using an ECU hemiband and preserving its distal insertion, which
is introduced through the diaphyseal canal and extracted through a hole in the dorsal
cortex of the ulna according to Minami's technique[.13] Subsequently, the surgeon proceeded to suture, concluding the stabilization.
Fig. 1 Arthroscopic image of the cruentation of the distal radioulnar joint (DRUJ) from
the dorsal distal radioulnar portal (d-DRU) with a 2.9-mm arthroscopic drill introduced
from the volar distal radioulnar portal (v-DRU). CU: ulnar head. FS: sigmoid fossa
of the radius.
Fig. 2 (a) Arthroscopic image of the temporary fixation of the distal radioulnar joint (DRUJ)
from the dorsal distal radioulnar portal (d-DRU). CU: ulnar head. FS: sigmoid fossa
of the radius. AAKK: Kirschner wire. (b) Anteroposterior intraoperative fluoroscopic image of the temporary DRUJ fixation
to ensure correct joint position.
Fig. 3 (a) Arthroscopic image of the definitive cannulated screw fixation of the distal radioulnar
joint (DRUJ) from the dorsal distal radioulnar portal (d-DRU). CU: ulnar head. FS:
sigmoid fossa of the radius. (b) Arthroscopic image of the cannulated screw compression at DRUJ from the dorsal distal
radioulnar portal (d-DRU). CU: ulnar head. FS: sigmoid fossa of the radius.
Fig. 4 Anteroposterior intraoperative fluoroscopic image of the definitive fixation of the
distal radioulnar joint (DRUJ) with correct arthrodesis using a cannulated screw.
Fig. 5 (a) Anteroposterior intraoperative fluoroscopic image after ulnar osteotomy and tendon
stabilization. (b) Lateral intraoperative fluoroscopic image after ulnar osteotomy and tendon stabilization.
After the intervention, the patient received a brachial splint with the wrist in a
neutral position for 2 weeks. After splint removal, an antebrachial splint was placed
with slight ulnar deviation so as not to stress the ECU for 3 or 4 weeks.
After splint removal, there is a first phase of pain and edema control, recovery of
joint movements in flexion-extension and prono-supination, and proprioceptive re-education
exercises for conscious articular control. In the second phase, not before the sixth
week, we worked on DRUJ's stabilizing muscle strengthening, ECU, and flexor carpi
ulnaris (FCU) concomitant contraction for proximal stump stabilization, and exercises
for unconscious neuromuscular control. In this last phase, the patient receives education
on specific activities.
Material and Methods
This retrospective study consisted of a case series of 11 patients operated on from
2015 to 2022 by the same team of hand surgeons using the S-K technique with arthroscopic
assistance and proximal tendon stabilization. The inclusion criteria were patients
with DRUJ arthropathy, whether primary or secondary to traumatic wrist injuries, and
high sports or work demands. We excluded patients undergoing arthropathy secondary
to rheumatic diseases or previously submitted to DRUJ arthropathy surgeries.
We analyzed age, laterality, cause, and associated injuries. We also clinically evaluated
flexion-extension and pronosupination mobility using a goniometer, pain with the visual
analog scale (VAS), the Disability of Arm, Shoulder, and Hand (DASH) score, the Mayo
Wrist Score (MWS), grip strength, and patient satisfaction preoperatively and at 1,
3, 6, and 12 months postoperatively. We compared the grip strength with the healthy
contralateral wrist using a Jamar® Hand Dynamometer (Sammons Preston, Bolingbrook,
IL, USA).
Radiological follow-ups occurred monthly, with anteroposterior (AP) and lateral radiographs
until confirming the consolidation of the arthrodesis between the sigmoid fossa and
the ulnar head.
We incorporated the data into a database created with Microsoft Excel 365 program.
The IBM SPSS version 28 program performed the statistical analysis. This analysis
consisted of a descriptive analysis of the variables, calculating the frequency distribution
for qualitative variables and the arithmetic mean and the standard error of the mean
(SEM) for quantitative variables. Statistical comparisons used a one-way analysis
of variance (ANOVA) for repeated measures with a posthoc Bonferroni multiple comparisons
test to determine statistically significant differences in mean values at several
evaluation times. Differences were statistically significant when p-values were lower
than 0.05.
Results
We analyzed 11 patients with secondary DRUJ osteoarthritis who underwent surgery using
the described technique (arthroscopic S-K with proximal tendon stabilization) ([Table 1]). The minimum follow-up was 12 months (range, 12 to 36 months) with a meantime of
19 months.
Table 1
|
Gener
|
10 males, 1 female
|
|
Age
|
39.1 ± 4.0 years old (range, 16 to 55)
|
|
Side
|
8 right; 3 left. 91% of dominant hand involvement
|
|
Cause
|
5 distal radius fractures consolidated in poor position (45.5%)
|
|
3 DRUJ dislocations (27.3%)
|
|
3 Chronic instabilities due to foveal lesion of the TFCC (27.3%)
|
Pain per the VAS scale significantly improved from the preoperative period to the
four postoperative evaluations. Moreover, there were significant differences between
each evaluation and the next up to the sixth month ([Fig. 6]). Joint balance also improved significantly in extension, flexion, pronation, and
supination ([Fig. 7]).
Fig. 6 Pain evaluation using the visual analog scale (VAS) before the intervention (pre)
and in the postoperative period (post 1, 3, 6, and 12 months). Data are expressed
as mean ± standard error of the mean (SEM). Significantly differences, * P < 0.05,
** P < 0.01, *** P < 0.001. 1. Pain (VAS), 2. Pre, 3. Post 1, 4. Post 3, 5. Post 6,
6. Post 12, 7. Time (months).
Fig. 7 Evaluation of the joint range in flexion (A), extension (B), pronation (C), and supination (D) (in degrees) before the intervention (pre) and in the postoperative period (post
1, 3, 6, and 12 months). Significantly differences, * P < 0.05, **P < 0.01, *** P < 0.001.
1. Flexion (grades), 2. Pre, 3. Post 1, 4. Post 3, 5. Post 6, 6. Post 12, 7. Time
(months), 8. Extension (grades), 9. Pre, 10. Post 1, 11. Post 3, 12. Post 6, 13. Post
12, 14. Time (months), 15. Pronation (grades), 16. Pre, 17. Post 1, 18. Post 3, 19.
Post 6, 20. Post 12, 21. Time (months), 22. Supination (grades), 23. Pre, 24. Post
1, 25. Post 3, 26. Post 6, 27. Post 12, 28. Time (months).
The grip strength presented a statistically significant difference between the preoperative
measurement and the four postoperative evaluations. The strength worsened in the first
postoperative month and increased from the third month onward. There were statistically
significant differences between each evaluation and the next ([Fig. 8]).
Fig. 8 Assessment of grip strength (in kg) before the intervention (pre) and in the postoperative
evolution (post 1, 3, 6, and 12 months). Significantly differences, * P < 0.05, ***
P < 0.001. 1. Grip (kg), 2. Pre, 3. Post 1, 4. Post 3, 5. Post 6, 6. Post 12, 7. Time
(months).
The Quick-DASH score ([Fig. 9]) for functional assessment revealed a significant improvement from the preoperative
period and the four postoperative assessments. In addition, there were significant
differences between each evaluation and the next up to the sixth month. The MWS score
improved significantly between the preoperative period and the assessment performed
12 months after surgery ([Fig. 10]).
Fig. 9 Results of the functional assessment with the Quick Disability of Arm, Shoulder and
Hand (DASH) score before the intervention (pre) and in the postoperative period (post
1, 3, 6, and 12 months). Significantly differences, ** P < 0.01, *** P < 0.001. 1.
Pre, 2. Post 1, 3. Post 3, 4. Post 6, 5. Post 12, 6. Time (months).
Fig. 10 Results of the functional assessment with the Mayo Wrist Score (MWS) before the intervention
(pre) and 12 months after the procedure (post 12). Significantly differences, ***
P < 0.001. 1. Pre, 2. Post 12, 3. Time (months).
All patients presented arthrodesis consolidation in an average period of 3.25 months
after surgery (range, 2.5 to 4 months).
Work and sports recovery with no limitations occurred in 10 patients (91%), while
one subject returned to work with restrictions. This last patient had a previous arthroscopic
foveal TFCC reattachment surgery that was unsuccessful due to the poor quality of
the repaired tissue. No patient presented osteotomy fusion or arthrodesis nonunion.
During the postoperative period, one patient had a sensation of instability of the
proximal stump one month after surgery, with complete resolution after forearm muscle
strengthening.
One subject presented pain 3 months postoperatively due to skin friction with the
head of the arthrodesis screw. The pain stopped after osteosynthesis material removal
after confirming complete DRUJ consolidation. Hardware removal was not necessary in
the remaining cases.
All patients declared their satisfaction with the outcomes at the end of the follow-up
period.
Discussion
The S-K technique for treating distal radioulnar arthropathy is a useful procedure
that improves the transmission pattern of loading forces from the hand to the forearm
by maintaining the ulnar head in normal alignment with the radius and carpus. This
alignment plays a major role in effective load transmission, especially in young patients
with high demands. This fact explains why S-K is the procedure of choice in these
subjects and active elderly patients with DRUJ osteoarthritis.[15] At the same time, maintaining the ulnar head brings some advantages due to ECU stabilization
in its compartment, ulnocarpal ligament sparing, and a more aesthetic wrist appearance.[16]
However, this procedure is not free of potential complications. Lluch[17] and Coulet et al.[18] described the complications directly related to the S-K technique, including nonunion
or delayed arthrodesis consolidation and failed arthrodesis resulting from incomplete
articular cartilage resection, incorrect Kirschner wire or screw placement or protrusion,
fibrous or bony union, and symptomatic instability of the proximal stump due to radioulnar
impingement or extensor tendon involvement. In our series, using the arthroscopic
S-K technique and proximal tendon stabilization, all cases presented arthrodesis consolidation,
and there was no case of osteotomy consolidation. Screw removal because of discomfort
was necessary in one patient.
The main complication described was painful instability of the proximal ulna stump,
which is usually difficult to correct.[19] Painful instability of the proximal ulna stump is more common after the S-K procedure
compared with the Darrach technique because the ulnar osteotomy is more proximal in
the S-K procedure. Since the axis of rotation of the forearm runs obliquely from the
center of the radial head proximally to the center of the ulnar head distally, the
osteotomy must be as close to the head of the ulna as possible. A more proximal osteotomy
will cause a motion divergence between the proximal stump and the ulnar head, which
was already attached to the radius. For all this, Lluch recommended performing the
osteotomy just proximal to the ulnar head, removing only 5 mm of bone to obtain the
best outcomes.[20] Another reason for performing the ulnar osteotomy as distal as possible is to avoid
altering the static structures and dynamics providing stability to the proximal ulna,
such as the pronator quadratus (PQ), ECU, and FCU muscles, and the interosseous membrane
(IOM) attachment. The PQ deep head is the main dynamic stabilizer of the proximal
ulna, and it is not advisable to use it as an interposition between both ends of the
ulna, as is done in several techniques. To avoid proximal stump instability, a tenodesis
with a tendon band of the ECU[13] or FCU[21] has been recommended, preserving its distal attachment to the pisiform bone. The
fibrous ECU tendon tunnel plays a significant role in DRUJ stabilization.[22] Although the arthrodesed ulnar head does not need the ECU for its stabilization,
it still provides some proximal stump stabilization, which is more effective if the
osteotomy is very close to the ulnar head, there is no tendon sheath division, and
the ECU is placed dorsal to the osteotomy. García-López et al.[23] presented a series of cases operated on using the open technique, in which six of
the 27 patients had symptomatic proximal ulnar stump instability. Two of their patients
required a new surgical intervention combining stabilization using the ECU and the
FCU. One patient presented postoperative sensory changes in the area of the dorsal
ulnar cutaneous branch, and two subjects had a lack of fusion of the arthrodesis at
one year of follow-up, which required a new surgical intervention to achieve it. In
two cases, there was no radiographical or clinical fusion. One patient continued to
present pain at the distal radioulnar level, which required a new intervention for
a distal radioulnar arthroplasty. In our series, there were no symptomatic instabilities
or nerve involvement, and no patient had pain at one year of follow-up. In addition,
there was no lack of arthrodesis or fusion consolidation at the osteotomy level. The
hemitendon stabilization of the ECU used by García-López et al. was a variant of the
Minami technique[13] in the form of a tie or scarf over the proximal ulnar stump and suturing the hemitendon
over itself but with no interposition at the osteotomy level.
In the series reported by García-López et al., 13 patients (48.15%) returned to work
with no limitations, 10 patients (37%) returned to work with restrictions, and three
patients (11.11%) were unable to return to work.[23] In contrast, in our series, 91% of the patients returned to their previous jobs,
and a single subject required a work readjustment.
Abe et al.[24] used the arthroscopic technique to stabilize the proximal stump by suturing the
PQ muscle and tightening the periosteum of the remaining ulna. However, 25% of their
patients presented discomfort in the proximal stump. These authors also reported five
tendon ruptures and five subjects required osteosynthesis material removal due to
pain. Our series had no tendon ruptures and a single patient required screw removal.
Carter and Stuart[25] published a series of complications in their study of 37 patients undergoing open
surgery. They observed that forearm rotation and grip strength were 92% and 62% compared
with the contralateral side, respectively. Nine patients (24%) complained of ulnar
stump pain, and five (14%) presented DRUJ nonunion. Voche et al.[26] reported 21 patients who underwent an open S-K procedure, with a mean forearm rotation
and grip strength of 87% and 55% compared with the contralateral side, respectively.
Eight patients presented stump instability, and three subjects had ossification of
ulnar arthrodesis. In our series, all patients had consolidated arthrodeses, no subject
presented pseudoarthrosis ossification, and there was a single case of sensation of
instability of the proximal stump one month after surgery. This instability resolved
completely with forearm muscle strengthening with no need for more interventions.
At the end of the follow-up, our patients had no pain (VAS, 0.45), presented almost
complete rotation (pronation, 87.30; supination, 87.30), and their strength improved
more than 100% compared with the preoperative period and an absolute value consistent
with the one described for healthy wrists by other studies.[27]
The S-K procedure also poses technical issues. Since it occurs on the hand table with
the forearm pronated, it is difficult to achieve an adequate reduction of the ulnar
head over the sigmoid fossa, sometimes resulting in a poor reduction with dorsal protrusion
of the ulnar head. Additionally, the extensor mechanism requires addressing to expose
the ulnar head, potentially leading to extensor tendon adhesion, even if repaired
afterward. With the arthroscopic technique, the visualization of the arthrodesis position
of the ulna head is direct, minimizing these risks.
Although the nonunion rate in the open S-K procedure remains unclear, some studies
have reported it as high.[17] This complication is minimized using arthroscopy, avoiding arthrotomy, and damaging
the vascular supply and capsular attachment of the DRUJ, and reducing the need for
bone grafting. Joint fusion using arthroscopic techniques has become popular in recent
years due to the preservation of the surrounding soft tissue providing vascularity
to the joint.[28] In our series, all patients had arthrodesis fusion with an average period of 3.25
months. This period is consistent with the report from Abe et al.,[24] who achieved bone union in all patients between 2 and 3.5 months after surgery.
In addition, arthroscopy allows a complete assessment of the joint status before making
decisions regarding the treatment and evaluating the exact amount of required joint
resection. The arthroscopy-assisted technique reduces postoperative pain and allows
a more comfortable rehabilitation start. The lack of arthrotomy avoids capsular, extensor
compartments, ligamentous, and nervous structures of the ulnar edge and reduces post-reconstruction
joint stiffness. Moreover, it preserves the ECU position intact because of the lack
of an incision and the vertical position of the wrist with neutral pronosupination.
The vertical placement of the wrist during arthroscopy facilitates the ulnar head
reduction over the sigmoid fossa of the radius. All this leads to an earlier mobility
improvement. Furthermore, arthroscopy minimizes the need for fluoroscopy since direct
visualization from the v-DRU portal allows us to see how the screw compresses the
DRUJ ([Fig. 3b]).
Luchetti et al.[2] published the results of the arthroscopic S-K technique with no proximal stump stabilization
with several advantages and favorable outcomes, no notable complications, a significant
increase in pronosupination strength and mobility, and a decrease in pain, which allowed
patients' return to their previous manual work. Regarding joint balance, our study
shows a statistically significant improvement in flexion-extension and pronosupination
arcs, as well as in subjective parameters and functional assessment scores. DASH,
MWS, and pain results are consistent with other studies using the arthroscopic technique.[2]
[29] In addition, the range of mobility in pronation and supination (> 87o) was superior in our series. The differentiating factor of our study is the addition
of tendon stabilization of the proximal stump since no long-term works demonstrate
the lack of stump instability symptoms.
Although, indeed, the distal location of the osteotomy, just proximal to the ulnar
neck, and the resection of a small amount of bone are essential to avoid instability
of the ulnar stump, and PQ interposition or other stabilization techniques were not
usually required, we advocate stabilization with ECU using the Minami technique[13] for two reasons. First, the interposition of the tendon through the diaphysis makes
the bone fusion of the osteotomy difficult, and second, a short osteotomy (5 to 8 mm)
spares the deep head of the tendon. The pronator teres is a palmar stabilizer of the
stump, but dorsal stabilization occurs with ECU tenodesis. Tomori et al.[12] demonstrated in their study with three different stump stabilization techniques
(without stabilization, with stabilization and an ECU hemiband from proximal to distal,
and with stabilization from distal to proximal)[13] that although there were no significant differences in wrist pain, ulnar stump pain
was significantly different between the non-stabilized group and the stabilized groups.
Conclusion
The arthroscopic S-K technique with proximal tendon stabilization is a safe, less
invasive, and effective procedure with better aesthetics and outcomes than the classic
open and arthroscopic technique with no tendon stabilization. However, further studies
are required to determine whether additional techniques are necessary to stabilize
the proximal stump.
