Arthroscopic evaluation of the foveal attachment of the triangular fibrocartilage

Structurally intact and functionally incompetent foveal triangular fibrocartilage complex injuries : an under-recognized spectrum of injury

Injury to the triangular fibrocartilage complex (TFCC) may result in ulnar wrist pain with or without instability. One component of the TFCC, the radioulnar ligaments, serve as the primary soft-tissue stabilizer of the distal radioulnar joint (DRUJ). Tears or avulsions of its proximal, foveal attachment are thought to be associated with instability of the DRUJ, most noticed during loaded pronosupination. In the absence of detectable instability, injury of the foveal insertion of the radioulnar ligaments may be overlooked. While advanced imaging techniques such as MRI and radiocarpal arthroscopy are well-suited for diagnosing central and distal TFCC tears, partial and complete foveal tears without instability may be missed without a high degree of suspicion. While technically challenging, DRUJ arthroscopy provides the most accurate method of detecting foveal abnormalities. In this annotation the spectrum of foveal injuries is discussed and a modified classification scheme is proposed.Cite this article: Bone Joint J 2023;105-B(1):5-10.

The Hook Test Is More Accurate Than the Trampoline Test to Detect Foveal Tears of the Triangular Fibrocartilage Complex of the Wrist

PURPOSE

To evaluate the accuracy of the trampoline and hook tests, used in the arthroscopic assessment of triangular fibrocartilage complex (TFCC) tears compared with arthroscopic direct visualization of the radiocarpal joint (RCJ) and of the distal radial ulnar joint (DRUJ).

METHODS

In total, 135 patients (97 male, 38 female, mean age 43.5 years) were divided into 2 groups: (1) 80 patients with chronic ulnar-sided wrist pain and positive fovea sign and (2) 55 patients with other complaints. TFCC was assessed by RCJ and DRUJ arthroscopy and by the trampoline and hook tests to detect rupture of distal and proximal components of the TFCC. Accuracy, specificity, sensitivity, and likelihood ratio of the 2 diagnostic methods were measured and compared, using RCJ and DRUJ arthroscopy as reference.

RESULTS

The trampoline and the hook tests showed an overall accuracy of 70.37% and 86.67%, respectively. The accuracy of the trampoline test was similar for distal (69%), proximal (66%), and complete (73%) TFCC tears. The hook test was more accurate when evaluating proximal (97%) and complete (98%) tears, rather than distal lesions (75%). Sensitivity for the trampoline and hook tests was 75.00% and 0.00% (P < .001) for distal tears and 78.85% and 100.00% (P < .001) and 58.33% and 100.00% (P < .001) for complete or isolated proximal tears, respectively. Specificity for the trampoline and hook tests was 67.27% and 96.36% (P < .001) respectively.

CONCLUSIONS

The trampoline and hook tests can assure accurate diagnosis of peripheral TFCC tear. The hook test shows greater specificity and sensitivity to recognize foveal TFCC tears. Values of positive likelihood ratio suggest a greater probability to detect foveal laceration of peripheral TFCC for the hook test than for the trampoline test. These findings suggest that DRUJ arthroscopy is not necessary to confirm foveal incompetence of the TFCC, if the hook test is positive.

LEVEL OF EVIDENCE

Level II, retrospective diagnostic trial.

Transulnar Styloid Foveal TFC Reconstruction: With a Palmaris Longus Tendon Graft

We describe an evolution of the senior author's technique in the repair or reconstruction of foveal triangular fibrocartilage complex tears. This technique uses a transulnar styloid approach, which gives superior access to the fovea, without disruption of secondary stabilizers. A free palmaris longus graft is used to stabilize and augment the triangular fibrocartilage complex with an interosseous anchor through an ulnar tunnel.

Arthroscopic Diagnosis of the Triangular Fibrocartilage Complex Foveal Tear: A Cadaver Assessment

PURPOSE

To determine whether the arthroscopic hook and trampoline tests are accurate and reliable diagnostic tests for foveal triangular fibrocartilage complex (TFCC) detachment.

METHODS

Wrist arthroscopy was performed on 10 cadaveric upper extremities. Arthroscopic hook and trampoline tests were performed and videos recorded (baseline). The deep foveal TFCC insertion was then sharply detached. Arthroscopic hook and trampoline tests were repeated. Subsequently, the foveal detachment was repaired via an ulnar tunnel technique and the hook test was repeated for a third time. Videos were independently reviewed at 2 time points by 2 fellowship-trained hand surgeons and 1 hand surgery fellow in a randomized and blinded fashion. Hook and trampoline tests were graded as positive or negative. Proportions of categorical variables were compared via 2-tailed Fisher exact test. Inter- and intraobserver reliabilities were assessed via Cohen kappa coefficient.

RESULTS

The sensitivity and specificity of the hook test for foveal detachment diagnosis were 90% and 90%, respectively. There was 90% agreement among all 3 observers for the baseline and foveal detachment hook tests. Cohen kappa coefficients for the inter- and intraobserver reliabilities of the hook test were 0.87 and 0.81, respectively. Seventeen percent of trampoline tests were positive at baseline versus 43% after foveal detachment. The trampoline test had 45% agreement between the 3 observers. Cohen kappa coefficients for the inter- and intraobserver reliabilities of the trampoline test were 0.16 and 0.63, respectively. Following ulnar tunnel repair, 20% of hook tests were positive.

CONCLUSIONS

The hook test is highly sensitive, specific, and reliable for the diagnosis of isolated TFCC foveal detachment. The trampoline test has insufficient reliability to assess foveal detachment. A TFCC foveal repair using an ulnar tunnel technique returns the hook test to baseline.

CLINICAL RELEVANCE

The hook test is a sensitive, specific, and reliable test for the diagnosis of isolated TFCC foveal detachment.

Diagnostic Wrist Arthroscopy

After reviewing this article, readers should have a comprehensive understanding of the indications for diagnostic arthroscopy, technical considerations in performing a systematic evaluation of the wrist, and limitations of this technique.

Técnica de reinserción foveal artroscópica sin nudos del fibrocartílago triangular con visión directa de la articulación radiocubital distal

El fibrocartílago triangular es una estructura de alta relevancia en la estabilidad de la articulación radiocubital distal. Su componente profundo es el más importante en esta función. Por ello, cuando clínicamente se precisa recuperar esta estabilidad, se debe apuntar a una técnica quirúrgica que permita reestablecer lo más anatómicamente este componente. Presentamos una técnica artroscópica, sin nudos, que mediante 2 portales accesorios a los radiocarpianos, el portal distal dorsal de la articulación radiocubital distal y el portal distal volar radioulnar, permite reinsertar el fibrocartílago triangular en su punto de origen, de forma anatómica mediante visión directa durante todo el procedimiento. Posibilita además cruentar la huella de inserción aportando factores biológicos autólogos, mejorando la interfase hueso-fibrocartílago y analizar el estado local del cartílago articular, lo que condicionará la posterior indicación quirúrgica.

Reconstruction of Chronic Foveal TFCC Tears with an Autologous Tendon Graft

Background A triangular fibrocartilage complex (TFCC) injury can produce distal radioulnar joint (DRUJ) instability. If the foveal attachment is avulsed, it translates distally. The footprint is separated from its origin and will become covered in synovitis, preventing healing. The authors describe a surgical technique for the treatment of instability of the DRUJ due to chronic foveal detachment of the TFCC. Technique The procedure utilizes a loop of autologous palmaris longus tendon graft passed through the ulnar aspect of the TFCC and through an osseous tunnel in the distal ulna to reconstruct the fovel attachment. Patients and Methods We report on nine patients with a mean age of 42. Median follow-up was 13 months. Results The median pain scores measured were reduced from 8 to 3 postoperatively, and all had a stable DRUJ. Conclusions This technique provides stability of the distal ulna to the radius and carpus, with potential for biologic healing through osseous integration. It is a robust, anatomically based reconstruction of the TFCC to the fovea that stabilizes the DRUJ and the ulnar-carpal sag.

Instability of the distal radioulnar joint

The distal radioulnar joint is a complex structure necessary for forearm motion and force transmission across the wrist. Anatomic and biomechanical advances have revealed broad contributions to distal radioulnar joint stability and refined our understanding of the forces acting across it. Instability often co-occurs with other modes of pathology, such as arthrosis or malunion; and appropriate diagnosis and treatment require a comprehensive understanding of all contributing factors. Distal radioulnar joint instability can be broadly categorized as primary, post-traumatic or post-surgical. Treatment strategies include percutaneous, arthroscopic, soft-tissue, osteotomy and arthroplasty techniques. The purpose of this article is to review distal radioulnar joint instability and its management.

Anatomic foveal reconstruction of the triangular fibrocartilage complex with a tendon graft

An acute injury to the triangular fibrocartilage complex (TFCC) with avulsion of the foveal attachment can produce distal radioulnar joint (DRUJ) instability. The avulsed TFCC is translated distally so the footprint will be bathed in synovial fluid from the DRUJ and will become covered in synovitis. If the TFCC fails to heal to the footprint, then persistent instability can occur. The authors describe a surgical technique indicated for the treatment of persistent instability of the DRUJ due to foveal detachment of the TFCC. The procedure utilizes a loop of palmaris longus tendon graft passed through the ulnar aspect of the TFCC and into an osseous tunnel in the distal ulna to reconstruct the foveal attachment. This technique provides stability of the distal ulna to the radius and carpus. We recommend this procedure for chronic instability of the DRUJ due to TFCC avulsion, but recommend that suture repair remain the treatment of choice for acute instability. An arthroscopic assessment includes the trampoline test, hook test, and reverse hook test. DRUJ ballottement under arthroscopic vision details the direction of instability, the functional tear pattern, and unmasks concealed tears. If the reverse hook test demonstrates a functional instability between the TFCC and the radius, then a foveal reconstruction is contraindicated, and a reconstruction that stabilizes the radial and ulnar aspects of the TFCC is required. The foveal reconstruction technique has the advantage of providing a robust anatomically based reconstruction of the TFCC to the fovea, which stabilizes the DRUJ and the ulnocarpal sag.

Arthroscopically assisted reconstruction of triangular fibrocartilage complex foveal avulsion in the ulnar variance-positive patient

PURPOSE

Our aim was to evaluate the clinical results of patients treated by arthroscopically assisted reconstruction of foveal avulsion injury of the triangular fibrocartilage complex (TFCC) using a suture anchor.

METHODS

We retrospectively reviewed the results of 15 patients (11 men and 4 women; mean age, 30.5 years) who underwent surgical procedures for the treatment of TFCC foveal avulsion at our hospital. The patients were followed up for a mean of 29 months. The patients had TFCC foveal avulsion caused by sprains (n = 8), falls (n = 4), playing baseball (n = 2), and a motor vehicle accident (n = 1). All the patients underwent magnetic resonance imaging. Radiographs obtained to assess ulnar variance (UV), ulnar-dorsal subluxation, and function of the wrist based on grip power; Disabilities of the Arm, Shoulder and Hand score; and Mayo wrist score were examined for all patients both preoperatively and postoperatively.

RESULTS

On preoperative magnetic resonance imaging, TFCC foveal avulsion was observed in 13 of 15 cases. The mean UV value based on preoperative simple radiographic findings was 1.7 ± 1.0 mm, and dorsal subluxation at the distal ulna improved from 2.9 ± 3.0 mm to 0.2 ± 0.9 mm (P = .017). In all cases the distal radioulnar joint instability disappeared postoperatively. Grip power (compared with the uninvolved limb) was 79.3% preoperatively and 82.9% postoperatively (P = .086). The Disabilities of the Arm, Shoulder and Hand scores were 28.4 points preoperatively and 16.6 points postoperatively (P = .061). The Mayo wrist scores were excellent in 10 cases, good in 2, and fair in 3, and the mean score improved significantly from 64 points preoperatively to 84 points postoperatively (P = .007).

CONCLUSIONS

Arthroscopic-assisted suture anchor reattachment of the TFCC in patients with traumatic TFCC foveal avulsion can prevent or reduce distal radioulnar joint instability and reduce pain even in chronic cases with positive UV.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

The effect of additional video documentation to photo documentation in wrist arthroscopies on intra- and interobserver reliability

INTRODUCTION

The reproducibility of diagnoses based on photo documents in wrist arthroscopies is limited and is expected to improve through the addition of video documents.

AIM

The purpose of this study was to determine the effect of additional video documentation to photo documentation on intra- and interobserver reliability in wrist arthroscopies.

MATERIALS AND METHODS

Sixty consecutive arthroscopies were documented by photographs of at least eight standard views and videos of the radiocarpal and midcarpal joints. After 3 months, the photographs and then the photographs together with the videos were reevaluated by the surgeon and by two hand surgeons to determine intra- and interobserver reliability. Percentage agreement and kappa coefficients were calculated.

RESULTS

Using videos along with the photographs did not improve reproducibility in general. The assessments of the cartilage status were even worse. Some of the videos were criticized as being too short to allow adequate assessment of the cartilage. Lesions of the TFCC as well as its tension were assessed notably better by the videos, whereas assessment of SL and LT ligaments was not improved by the videos. Intraobserver reliability was better than interobserver reliability.

CONCLUSION

As long as videos do not meet further quality criteria, they are not able to improve reliability in general. Nevertheless, videos should be used for documentation of the TFCC.

Anatomic reconstruction of the radioulnar ligament

INTRODUCTION

Twenty-five patients (19 males and six females) were included in the study based on: chronic symptoms of distal radioulnar joint instability, demonstrable instability on examination, MRI evidence of radioulnar ligament deficiency, and arthroscopic findings of foveal disruption of the radioulnar ligament.

MATERIALS AND METHODS

Exclusion criteria were: distal radius malunion, congenital malformation of the sigmoid notch, DRUJ arthritis, and less than 24 months minimum follow-up. Mean age was 35 years old with a mean interval from injury to surgery of 5 months. Surgery began with arthroscopic confirmation of the chronic foveal detachment followed by open reconstruction of the radioulnar ligament using the palmaris longus tendon. The specific method employed three drill tunnels corresponding to the true anatomic points of attachment of the radioulnar ligament. Patients were examined post-operatively at 2 weeks, 4 weeks, 6 weeks, 12 weeks, and 6 months.

RESULTS AND DISCUSSION

Final evaluation averaged 51 (±14) months following surgery. Measures obtained before and after treatment included: wrist range of motion, forearm range of motion, grip strength, examination findings of distal radioulnar joint instability, and Disabilities of Arm, Shoulder, and Hand (DASH) scores. Pre-operative and post-operative measures were compared using the paired Student's t test, accepting a p value of 0.05 as statistically significant. All patients healed the reconstruction without major complications and demonstrated distal radioulnar joint stability at the 6-week examination. Mean ranges of motion, in degrees, pre-/post-operative were: wrist flexion 53 (±13)/61 (±10), wrist extension 53 (±13)/62 (±15), supination 65 (±12)/74 (±7), and pronation 66 (±11)/71 (±8). Grip strengths expressed as % contralateral pre-/post-operative were: 57 (±23)/79 (±25). The differences in these measures were not found to be statistically significant. The mean pre-/post-operative DASH scores were: 62 (±16)/7 (±3). This difference was found to be statistically significant.

CONCLUSION

Reconstruction of the RUL with a free palmaris longus tendon graft using the truly anatomic points of original RUL attachment at both the ulna and radius restored DRUJ stability and improved DASH scores without limiting forearm or wrist motion.

The effect of labeling photo documents in wrist arthroscopies on intra- and interobserver reliability

INTRODUCTION

The reproducibility of diagnoses based on photo documents in wrist arthroscopies is limited and is expected to improve if the photos are labeled with illustrated structures.

AIM

The purpose of this study was to determine the effect of labeling photo documents on intra- and interobserver agreement and reliability of standard photo documentation in wrist arthroscopies.

MATERIALS AND METHODS

Digital photographs of 50 arthroscopies were re-evaluated by the surgeon as well as by two independent hand surgeons. First the photos were presented unlabeled in a random order, then the labeled photos in a uniform order. Intra- and interobserver reliability was assessed, and expressed by kappa coefficients.

RESULTS

Overall, labeling the photos resulted in a slight improvement in intra- and interobserver reliability (0.573/0.444/0.420 vs. 0.518/0.412/0.212). The time needed to conceive the photo documents, however, was shortened when the photos were labeled. The cartilage status was assessed considerably more accurately if the photos were labeled (0.556/0.560/0.422 vs. 0.459/0.326/0.240; t test: P = 0.094). Whereas the SL ligament was assessed more accurately according to labeled photos (P = 0.100), the agreement rates for the assessment of other ligament structures (TFCC, LT and radiopalmar ligaments) were not substantially affected by labeling the photos. On re-evaluation of the unlabeled as well as the labeled photos, intraobserver reliability was better than interobserver reliability (0.518 vs. 0.412/0.212 and 0.573 vs. 0.444/0.420).

CONCLUSION

Labeling simplifies but does not necessarily improve the reproducibility of photo documents in wrist arthroscopies. To display the cartilage status and the integrity of the SL ligament, digital photo documents should be labeled with the illustrated structure or joint surface.