DRUJ Capsular Release for Forearm Rotational Limitation: Surgical Technique and Case Series

Abstract

Background:

Forearm stiffness can be caused by distal radioulnar joint (DRUJ) capsular contractures, which can occur after trauma such as a distal radius fracture. In this setting, a DRUJ capsular release may help improve forearm rotation, but the long-term functional outcomes remain unknown. The purpose of this case series is to investigate the short-term improvement in total pronosupination arc range of motion and long-term patient-reported outcomes (PROs) after DRUJ capsular release.

Methods:

We performed a retrospective review of consecutive patients who underwent DRUJ capsular release. Range of motion prior to surgery and at final short-term follow-up was collected and analyzed with a Wilcoxon signed-rank test. Patient-reported outcomes including QuickDASH and Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity (UE) scores were obtained as medians with interquartile range (IQR), while patient satisfaction was measured on a 4-point Likert scale.

Results:

Five patients met the inclusion criteria with a median short-term follow-up of 5.5 (IQR: 4.3-10.3) months. The median preoperative supination was 25° (IQR: 0°-35°), and the median postoperative supination was 50° (IQR: 40°-60°; P = .03). The median preoperative pronation was 45° (IQR: 10°-60°), and the median postoperative pronation was 70° (IQR: 60°-80°; P = .04). After the long-term median follow-up of 10.9 (IQR 9.7-11.2) years, all the patients were satisfied or very satisfied with the results of the surgery. The median QuickDASH score was 13.6 (IQR: 9.1-20.5), and the median PROMIS UE score was 46.5 (IQR: 43.8-47.7).

Conclusions:

Distal radioulnar joint capsular release can improve pronation and supination in patients with posttraumatic forearm stiffness and is associated with high long-term patient satisfaction.

Introduction

Distal radioulnar joint (DRUJ) capsular contractures can cause forearm stiffness that can be challenging to treat.^1,2 It is occasionally observed in distal radius fractures and may limit motion even after bony geometry and alignment have been restored. ³ The underlying limitation in rotation presumably occurs secondary to capsular contracture of the DRUJ. ² In these cases, capsular release is an option to improve forearm rotation.^4,5

Kleinman and Graham extensively described the anatomy of the DRUJ capsule, as well as a technique to release the DRUJ. Kleinman and Graham described 3 aspects of the DRUJ capsule: inferior, volar, and dorsal which were distinct from the central disk (triangular fibrocartilage complex [TFCC]). Moreover, they noted that the DRUJ capsule can be identified as the source of pronosupination failure in patients who have fully recovered osseous anatomy after trauma but have not achieved pronosupination following maximal rehabilitation. The authors described releasing the volar DRUJ capsule to improve forearm supination and releasing dorsal DRUJ capsule to improve forearm pronation. To avoid TFCC damage the DRUJ arthrotomy on the volar side was initiated with a transverse incision along the distal articular margin of the ulna, which was referred to as the “pole” of the ulna (Figure 1b). During this procedure, great care was taken to protect the volar radioulnar ligament. The arthrotomy on the dorsal side was initiated by first introducing a 20-gauge needle, as a guide, into the joint space between the distal pole of the ulna and the TFCC to avoid injury to the dorsal radioulnar ligament (Figure 2b). All patients in their series had improved forearm rotation without complications or joint instability. ¹

Figure 1.

Intraoperative photographs demonstrating the thickened and contracted volar distal radioulnar joint (DRUJ) capsule.

Note. (a) The arthrofibrosis of the DRUJ capsule and PQ muscle contractures are visualized. (b) Demonstration of the volar capsulectomy and PQ muscle detachment. (c) Further muscle detachment and visualization of the DRUJ intraarticular fibrosis. (d) The complete excision of the volar DRUJ capsule was achieved by elevating off its attachments to the triangular fibrocartilage complex and radius to protect these underlying structures then transecting from its attachment to the ulna. PQ = pronator quadratus.

Figure 2.

Cadaveric dissections demonstrating the dorsal approach to DRUJ capsular release.

Note. (a) Opening the fifth dorsal extensor compartment and retracting EDM. (b) The pin is located in the ulnocarpal joint distal to the ulnar head and proximal to the triangular fibrocartilage complex (TFCC). (c) Demonstration of the dorsal capsule incision. (d) The complete excision of the dorsal DRUJ capsule was achieved by elevating off its attachments to the TFCC and radius to protect these underlying structures then transecting from its attachment to the ulna. DRUJ = distal radioulnar joint; EDM = extensor digiti minimi.

Although the results of Kleinman are promising, limited literature exists on the functional outcomes and patient-reported outcomes (PROs) after DRUJ capsular release. Therefore, the purpose of this study is to further investigate functional outcomes and PROs from DRUJ capsular release for forearm rotational limitation after a distal radius fracture.

This case series reports our experience with DRUJ capsular release regarding range of motion (ROM) and long-term functional outcomes.

Material and Methods

A retrospective study was performed with approval of the institutional review board. Data were collected from an institutional database for all relevant orthopedic encounters from January 1, 2002, to December 31, 2016. Current Procedural Terminology (CPT) codes and manual chart reviews were used to identify patients that underwent a DRUJ capsular release for forearm stiffness. The included CPT codes were 29844, 29845, 29846, 25085, 25320, 25337, 25259, and 25107 (Supplemental Appendix 1). We included patients that were treated for limited forearm rotation after sustaining a distal radius fracture. Patients were excluded if they had insufficient preoperative documentation of ROM and/or loss to follow-up. In addition, patients were excluded if imaging demonstrated DRUJ incongruency; if there were concurrent bony procedures such as distal radius osteotomies or distal ulna resection; concurrent elbow capsulectomy; history of DRUJ instability; unclear diagnosis for forearm stiffness; and prior surgeries for forearm stiffness or congenital problems such as forearm synostosis and paralytic contractures leading to lack of forearm rotation. Of the 91 patients initially identified through CPT codes, 25 underwent a DRUJ capsular release. The other 66 patients underwent an arthrodesis, capsulectomy in hand/wrist not related to forearm rotation, manipulation under anesthesia, and Darrach procedure or Sauve-Kapandji procedure. The charts and medical data for the 25 patients were carefully reviewed, leading to identification of 5 patients who met the inclusion criteria. Ten patients were excluded due to insufficient preoperative documentation of ROM and/or loss to follow-up: 5 were excluded due to concurrent procedures (radius osteotomy [3×], elbow capsule release, and Darrach resection with tenodesis), 4 were excluded due to a history of DRUJ instability, and 1 was excluded due to an unclear diagnosis for forearm stiffness.

Data collected included patient demographics, details about the primary pathology that subsequently necessitated DRUJ capsular release, as well as the initial management of the primary pathology, ROM prior to DRUJ capsular release, surgical technique and postoperative immobilization, complications resulting from DRUJ capsular release, and short-term follow-up metrics including time to follow-up and active ROM at follow-up from the last visit note.

Patient-reported outcomes were obtained by phone from the patients including QuickDASH and Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity (UE) version 2.0 scores. Patients also completed a survey to assess whether they required additional procedures after their initial DRUJ capsular release and their satisfaction with the surgery, which was registered on a 4-point Likert scale ranging from “very satisfied” to “not satisfied.”

Indication for DRUJ Capsular Release

All patients had functionally limited forearm rotation that interfered with their activities of daily living despite maximal efforts with occupational therapy. Patients with bony abnormalities requiring other or concurrent procedures such as a distal radius osteotomy were not included in this study. The subset of patients included in this study had isolated DRUJ capsular release as it was determined that additional bony procedures would not be needed based on their imaging (Figure 3) and examination.

Figure 3.

The last radiographs obtained before distal radioulnar joint capsular release. Case 1: open reduction and internal fixation (ORIF); case 2: external fixation; case 3: ORIF; case 4: conservative; case 5: ORIF.

Operative Technique

All procedures were performed by two attending fellowship-trained hand and UE surgeons. Under tourniquet control, a volar approach to the wrist was made via an incision directly onto the flexor carpi ulnaris (FCU) tendon. The fascia was freed up on the radial side of the FCU tendon to identify and protect the ulnar neurovascular bundle. The ulnar neurovascular bundle was retracted ulnarly, whereas the flexor tendons were retracted radially. The thickened DRUJ capsule was identified (Figure 1a). The volar DRUJ capsule was excised without injuring the TFCC (Figure 1b). As described by Kleinman and Graham, complete excision of the volar DRUJ capsule was achieved by first dissecting off its insertion on the radius then following the contour of the ulna proximally to the portion that articulates with the sigmoid notch of the radius (Figure 1b). At this point, supination was assessed intraoperatively. If full supination could not be achieved, then the insertion of the pronator quadratus (PQ) was released from its ulnar border (Figure 1b). If the supination is still limited, PQ can be released further (Figure 1c) and sometimes there can be fibrosis in the sigmoid notch and this can be fully released (Figure 1d).

In a simultaneous or separate dorsal DRUJ approach to improve forearm pronation, access was obtained through the fifth dorsal compartment. The extensor digiti minimi was retracted from the fifth dorsal compartment (Figure 2a) and elevated to expose the floor of the compartment (Figure 2b). The DRUJ capsule and distal interosseous space were exposed (Figure 2c). The dorsal DRUJ capsule was excised (Figure 2d). If the interosseous membrane is found to be excessively thickened, consider its release.

Statistical Analysis

All data were reported as medians with interquartile range (IQR). In bivariate analyses, a Wilcoxon signed-rank test was used to identify statistically significant associations between preoperative and postoperative ROM values in pronation and supination. A P value of less than .05 was set as statistically significant.

Results

Patient Clinical Characteristics

Five patients met the inclusion criteria (Table 1). There were 4 female and 1 male patients. All patients were white. The median age at DRUJ capsular release was 43 (IQR: 42-44) years. The primary pathology in all patients was a previous distal radius fracture. Of these patients, 3 underwent open reduction and internal fixation, 1 patient underwent external fixation and closed reduction percutaneous pinning, and 1 patient was managed conservatively. Indications for DRUJ capsular release were limited forearm mobility (n = 4) and limited forearm mobility with pain (n = 1). The median time from injury to surgery was 12.2 (9.9-16.9) months. There were no other procedures performed between the initial treatment of the distal radius fractures and the DRUJ capsular releases. Procedures that were performed simultaneously during DRUJ capsular release were plate removal and tenolysis of the extensor pollicis longus, extensor digitorum communis, and carpi radialis brevis and longus for 1 patient. Osteophyte excision for 1 patient and removal of plates for 2 patients were performed. Postoperatively, 3 patients received a soft dressing and started early active ROM, as well as passive ROM. One patient received a supination splint and came out of the splint several times a day to work on ROM of the forearm. The splint was slowly weaned off over the next few weeks. For the last patient, a splint was applied for 2 weeks in the position that the arm was stiff in, after which the patient started ROM with the assistance of a dynamic splint that allows for passive forearm rotation.

Table 1.

Patient Characteristics, Procedure Details, and Range of Motion.

Demographics				DRUJ capsular release features				Supination ROM		Pronation ROM
Patient	Gender	Ethnicity	Age, y	PQ release	Interosseous membrane release	Volar DRUJ capsule release	Dorsal DRUJ capsule release	Preoperative, (degrees)	Postoperative, (degrees)	Preoperative, °(degrees)	Postoperative, °(degrees)
1	Female	White	44	No	No	No	Yes	45	60	10	80
2	Male	White	43	Yes	No	Yes	No	25	65	80	80
3	Female	White	57	No	No	Yes	No	0	40	45	70
4	Female	White	31	No	No	Yes	Yes	0	40	0	40
5	Female	White	42	No	No	Yes	No	35	50	60	80

Note. DRUJ = distal radioulnar joint; PQ = pronator quadratus; ROM = range of motion.

Distal Radioulnar Joint Capsular Release

Release of the DRUJ capsule was performed in all patients. Of the 5 patients, 3 underwent volar capsule release without dorsal release, 1 underwent dorsal release without volar release, and 1 patient underwent both volar and dorsal releases. In addition, 1 patient underwent a release of the PQ muscle (Table 1). Postoperative immobilization strategies differed between patients. Splints were used in 2 patients; one of the patients received a regular arm splint, whereas the other patient received a splint in supination per surgeon preference. The other patients were placed in soft dressings postoperatively. One of the soft dressings was converted to a Joint Active Systems splint at first occupational therapy appointment. All patients performed occupational therapy postoperatively.

Outcomes

The median preoperative supination was 25° (IQR: 0°-35°) and the median pronation was 45° (IQR: 10°-60°). At the final short-term follow-up (median 5.5 [IQR: 4.3-10.3]) months, the median supination was 50° (IQR: 40°-60°) and the median pronation was 70° (IQR: 60°-80°). When comparing preoperative and postoperative ROM, both the changes in supination (P = .03) and pronation (P = .04) were statistically significant.

Complications

There were no intraoperative complications reported. In addition, no complications were reported in the immediate perioperative period or during the short-term follow-up period.

Patient-Reported Clinical Outcomes

All patients completed the PROs survey. The median time from date of surgery to survey completion was 10.9 (IQR: 9.7-11.2) years. All patients were either satisfied or very satisfied with the results of the surgery (Table 2). One patient underwent an additional procedure related to her wrist which involved removal of hardware for flexor tendon irritation. Three of 5 patients (60%) reported that they would undergo the procedure again, while 1 patient was unsure and 1 patient would not repeat the surgery. The median QuickDASH score was 13.6 (IQR: 9.1-20.5). The median PROMIS UE score was 46.5 (IQR: 43.8-47.7; Table 2).

Table 2.

Patient-Reported Outcomes.

Questionnaires (n = 5)	Score
QuickDASH, median (IQR)	13.6 (9.1-20.5)
PROMIS UE, median (IQR)	46.5 (43.8-47.7)
Satisfied or very satisfied, %	100

Note. PROMIS UE = Patient-Reported Outcomes Measurement Information System Upper Extremity; IQR = interquartile range.

Discussion

In our case series, we found considerable improvement of pronosupination at short-term follow-up following release of the DRUJ capsule in patients with a forearm rotation contracture after a distal radius fracture. Most patients reported high satisfaction with the procedure and reasonable PROs at long-term follow-up.

Kleinman and Graham reported the results of surgical DRUJ capsulectomy in patients with recalcitrant limited forearm pronosupination. ¹ In their case study of 9 patients, a volar DRUJ capsulectomy was performed in patients with posttraumatic loss of supination; in addition, in 3 patients with less than 50° of pronation, a dorsal capsulectomy was concurrently performed. All patients demonstrated marked improvement in forearm rotation and rated the surgery as successful. However, there have been no further publications regarding functional outcomes or PROs of open DRUJ capsular release since this initial study.

Interestingly, Kamal and Ruch demonstrated that capsular releases of the wrist in an effort to primarily regain wrist extension coincidentally showed concomitant improvement in pronosupination. ⁶ An open volar capsular release during the concomitant removal of prior distal radius hardware in which about 50% of the capsule was released led to an average improved supination by 23° and pronation by 14°. ⁶ The findings of improvement in pronosupination after wrist capsule release may be related to the anatomic confluence between the wrist capsule and the DRUJ capsule. However, this study is limited as most of the included patients did not have significant preoperative deficits in the pronosupination arc, with average preoperative pronation of 61.5° and the average supination of 49.3°, but rather primarily lacked wrist extension, which significantly improved after the procedure.

Our study builds on the prior literature by investigating the effect of DRUJ capsular release on total pronosupination arc of motion as well as long-term clinical outcomes. All patients who underwent the capsular release achieved full supination intraoperatively and showed statistically significant improvement in ROM in both supination and pronation at last follow-up postoperatively compared with preoperative ROM. Range of motion at an average 8-month follow-up remained significantly increased compared with preoperative ROM. Functional outcomes at long-term follow-up show high patient satisfaction from this procedure.

Kleinman described the DRUJ capsule as a self-contained anatomically distinct structure despite its confluence with the radioulnar ligament. ³ Through a silhouette approach, they demonstrated that in posttraumatic contractures, loss of forearm supination resulted in contractures of the volar capsule, whereas loss of pronation resulted from pathology in dorsal capsule. In addition to the DRUJ capsule, the PQ and intraosseous membrane contribute to the stability of the forearm during rotation. Contractures in any of these components of forearm rotation can contribute to potential stiffness in the pronosupination arc. In posttraumatic stiffness after a distal radius fracture, release of a constricted DRUJ capsule led to improvement in pronosupination ROM in our series.

One alternative to open DRUJ capsular release for improving rotational forearm stiffness is arthroscopic arthrolysis. Del Piñal et al describe an arthroscopic technique using a slightly curved rib periosteal elevator in the 6R portal to release volar adhesions in the DRUJ capsule, with a net improvement of 80° of supination (range: 50°-90°) in their case series of 6 patients. ⁵ Of note, this technique requires significant arthroscopic expertise and outcomes might not be reproducible by less experienced surgeons. In contrast, open DRUJ capsular release is relatively straightforward and therefore may be more easily adopted into clinical practice.

The PROMIS UE and QuickDASH have previously been validated to measure physical function and clinical outcomes in patients with UE limitations.^{7 -9} The PROMIS UE instruments were designed and validated to have a mean score of 50 with a SD of 10 in a reference cohort. In our cohort, 4 out of 5 patients reported PROMIS UE scores that fell within 1 SD of the scores found in the general population. The literature reports a long-term mean QuickDASH score after adequate reduction and recovery of a distal radius fracture of 4.5. ¹⁰ In our study the average QuickDASH score was 13.6, whereas the average PROMIS UE score was 46.5. In addition, all the patients expressed that they were either satisfied or very satisfied with the procedure and its results. Therefore, our results indicate that DRUJ capsular release may be efficacious, well-tolerated, and safe in this patient population.

Potential adverse effects of DRUJ capsular release include DRUJ instability. While there were no complications reported in our patient cohort, careful attention to the surgical technique and preventing damage to the important volar and dorsal radioulnar ligaments remain critical.

The results of this study should be viewed in the context of its limitations. The questionnaires were not obtained preoperatively; therefore, we were unable to compare preoperative results with the postoperative results. In addition, this is a small cohort of patients that is vulnerable to small sample effects. In addition, the ROM values reported were from final follow-up. We did not have in-person long-term follow-up.

In conclusion, in patients that have refractory, diminished pronosupination after distal radius fracture, surgery can yield improvements in function and ROM. This study further supports the initial studies by others that DRUJ capsular release may be beneficial.