Feasibility of a New Pulley Repair: A Cadaver Study

Comparison of 3T and 7T magnetic resonance imaging for direct visualization of finger flexor pulley rupture: an ex-vivo study

OBJECTIVE

To compare image quality and diagnostic performance of 3T and 7T magnetic resonance imaging (MRI) for direct depiction of finger flexor pulleys A2, A3 and A4 before and after artificial pulley rupture in an ex-vivo model using anatomic preparation as reference.

MATERIALS AND METHODS

30 fingers from 10 human cadavers were examined at 3T and 7T before and after being subjected to iatrogenic pulley rupture. MRI protocols were comparable in duration, both lasting less than 22 min. Two experienced radiologists evaluated the MRIs. Image quality was graded according to a 4-point Likert scale. Anatomic preparation was used as gold standard.

RESULTS

In comparison, 7T versus 3T had a sensitivity and specificity for the detection of A2, A3 and A4 pulley lesions with 100% vs. 95%, respectively 98% vs. 100%. In the assessment of A3 pulley lesions sensitivity of 7T was superior to 3T MRI (100% vs. 83%), whereas specificity was lower (95% vs. 100%). Image quality assessed before and after iatrogenic rupture was comparable with 2.74 for 7T and 2.61 for 3T. Visualization of the A3 finger flexor pulley before rupture creation was significantly better for 7 T (p < 0.001). Interobserver variability showed substantial agreement at 3T (κ = 0.80) and almost perfect agreement at 7T (κ = 0.90).

CONCLUSION

MRI at 3T allows a comparable diagnostic performance to 7T for direct visualization and characterization of finger flexor pulleys before and after rupture, with superiority of 7T MRI in the visualization of the normal A3 pulley.

Nonoperative Treatment of Finger Flexor Tenosynovitis in Sport Climbers—A Retrospective Descriptive Study Based on a Clinical 10-Year Database

Simple Summary

Finger flexor tenosynovitis is among the most frequent overuse injuries in sport climbers. Targeted therapy is currently based mostly on reports of the anecdotal practical experience of single centers rather than scientific investigations, as there is very little research available on this pathology. The aim of this study was to describe the nonoperative treatment outcomes of finger flexor tenosynovitis treatments in sport climbers by retrospectively asking patients about injury triggers, therapy contents and outcomes. All patients were initially treated conservatively, and only one of the patients needed further therapy in the form of a single injection with hyaluronic acid; none of them underwent further operative treatment. The average symptom duration was 30.5 weeks, and all patients were able to resume climbing, with approximately 75% of them regaining or exceeding their initial climbing level. These good to excellent outcomes and no correlation between particular therapy contents and therapy outcome suggest that finger flexor tenosynovitis in sport climbers has a favorable natural course without requiring invasive therapy. However, further cohort studies and, ultimately, randomized controlled trials are needed to conclusively confirm our promising observations from this study.

Abstract

The aim of this study was to describe the nonoperative treatment outcomes of finger flexor tenosynovitis in sport climbers and to evaluate the association with baseline measures and therapy contents. Sixty-five sport climbers (49 males, mean age 34.1 years) diagnosed with tenosynovitis of the finger flexors were retrospectively asked about injury triggers, therapy contents and outcomes. Pulley thickness was measured by ultrasound. All patients were initially treated conservatively, and only one of the patients needed further therapy (single injection with hyaluronic acid); none of them underwent surgical treatment. The most frequently applied therapy was climbing-related load reduction (91%). The treatment resulted in a statistically significant reduction in pain intensity during climbing (before/after therapy ratio [Visual Analog Scale (VAS)/VAS] = 0.62, 95% CI = 0.55, 0.68). The average duration of the symptoms was 30.5 weeks (range 1–120 weeks). In a multiple linear regression analysis, initial daily life pain intensity and a climbing level higher than 7b according to the French/sport grading scale were the only predictive parameters for the relative change in pain intensity and symptom duration, respectively. All patients were able to resume climbing, with 75% regaining or even exceeding their initial climbing level. The good to excellent outcomes and no correlation between particular therapy contents and therapy outcome may suggest that finger flexor tenosynovitis in sport climbers has a favorable natural course without requiring invasive therapy. However, further cohort studies and, ultimately, randomized controlled trials are needed to conclusively confirm our promising observations.

MRI of Finger Pulleys at 7T-Direct Characterization of Pulley Ruptures in an Ex Vivo Model

The aim of this study was to evaluate 7 Tesla (7T) magnetic resonance imaging (MRI) for direct visualization and specific characterization of the finger flexor pulleys A2, A3, and A4 before and after ex vivo pulley rupture. Thirty fingers of human cadavers were examined before and after pulley disruption with a 26 min clinical 7T pulse sequence protocol. Images were assessed by two experienced radiologists for the presence of pulley rupture. Injury characterization included definition of rupture location, morphology, and complications. Image quality was evaluated according to a 4-point Likert-type scale from “not evaluable” to “excellent”. Macroscopic preparations were used as the reference standard. Direct characterization of intact A2, A3, and A4 pulleys and the corresponding pulley lesions was possible in all cases. The rupture location was distributed equally at the radial, ulnar, and central parts of the pulleys. A dislocation and intercalation of the pulley stump between the flexor tendon and finger phalanges was observed as a complication in 62.5% of cases. The average Likert score for direct visualization of pulleys was 2.67 before rupture and 2.79 after rupture creation, demonstrating adequate image quality for routine application. 7T MRI enables a direct characterization of A2, A3, and A4 pulleys before and after artificial disruption, including the definition of rupture morphology and location as well as the detection of rupture complications. This promises a precise presurgical evaluation of pulley injuries and complicated pulley stump dislocations.

Evaluation of A2 and A4 Hand Pulley Repair Using Tendon Graft Rings

PURPOSE

To compare the mechanical characteristics of A2 and combined A2-A4 pulley repair in the intact and damaged flexor pulley system.

METHODS

After control testing, we recorded tendon excursion and flexion of 11 cadaveric fingers after several interventions: (1) complete excision of A2 and A4, (2) repair of the A2 with one ring of tendon graft, (3) repair of the A2 with 2 rings of tendon graft, and (4) repair of the A2 with 2 rings combined with repair the A4 with one ring.

RESULTS

At the proximal interphalangeal (PIP) joint, the maximum rotational angle decreased by an average of 30% after complete excision of the A2 and A4 pulleys. This angle was still decreased compared with the control by an average of 25% after one-ring repair at A2, 23% after 2-ring repair at A2, and 17% after 2-ring repair at A2 combined with one-ring repair at A4. At the metacarpophalangeal joint, the average maximum rotational angle decreased by an average of 17% after complete excision of the A2 and A4 pulleys. This angle was still decreased compared with the control by an average of 11% after one-ring repair at A2, 7% after 2-ring repair at A2, and 4% after 2-ring repair at A2 combined with one-ring repair at A4. Kinematic behavior at the PIP joint with an intact pulley system was most closely approximated by the 3-loop repair. The least similar behavior was with a 2-ring construct at A2.

CONCLUSIONS

All repairs increased average flexion at the PIP and metacarpophalangeal joints compared with the unrepaired samples. The 3-ring configuration exhibited a higher recovery of PIP flexion compared with the other repairs.

CLINICAL RELEVANCE

Although each repair restored flexion, clinical studies are necessary to evaluate the clinical relevance of the mechanical results of this study.

Finger Flexor Pulley Injuries in Rock Climbers

Finger flexor pulley system injuries are the most common overuse injury in rock climbers. These injuries occur rarely outside of rock climbing, owing to the sport's unique biomechanical demands on the finger. As rock climbing continues to grow and earn recognition as a mainstream sport, an understanding of how to diagnose and treat these injuries also has become important. Our purpose is to describe current concepts in anatomy, biomechanics, clinical evaluation, imaging, prevention, and treatment strategies relating to finger flexor pulley system injuries. Our literature search was performed on PubMed with MeSH terms and keywords as subject headings to meet the objectives of this review. The "crimp grip" used in rock climbing is the mechanism for these injuries. The A2, A3, and A4 pulleys are at the highest risk of injury, especially when loaded eccentrically. Physical examination may reveal clinical "bowstringing," defined as the volar displacement of the flexor tendons from the phalanges; however, imaging is required for characterization of the underlying injury. Ultrasound is highly sensitive and specific for diagnosis and is recommended as the initial imaging technique of choice. Magnetic resonance imaging is recommended as an additional imaging study if ultrasound is inconclusive. Properly warming up increases the amount of physiologic bowstringing and is thought to prevent injury from occurring. Pulley injuries may be classified as grade I through IV. Conservative treatment, including immobilization, the H-tape method, and the use of a protective pulley splint, is recommended for grade I to III injuries. Surgical repair is reserved for grade IV injuries that are not amenable to conservative treatment.

Olympic competition climbing: the beginning of a new era-a narrative review

Climbing as a competition sport has become increasingly popular in recent years, particularly the sub-discipline of bouldering. The sport will debut in the Tokyo Summer Olympic Games. National and international competitions have three disciplines: lead (climbing with rope protection), bouldering (climbing at lower heights with mattress floor protection) and speed (maximum speed climbing on a standardised route in 1-on-1 mode). There is also a 'combined mode' of all three disciplines (combined) which forms the Olympic competition format; all competition formats are held on artificial walls. Existing literature describes a predominantly low injury frequency and severity in elite climbing. In comparison to climbing on real rock, artificial climbing walls have recently been associated with higher injury rates. Finger injuries such as tenosynovitis, pulley lesions and growth plate injuries are the most common injuries. As finger injuries are sport-specific, medical supervision of climbing athletes requires specific medical knowledge for diagnosis and treatment. There is so far little evidence on effective injury prevention measures in top athletes, and antidoping measures, in general, requiring further work in this field. An improved data situation regarding high-performance climbing athletes is crucial to ensure that the sport continues to be largely safe and injury-free and to prevent doping cases as extensively as possible.

Feasibility of Homodigital Flexor Digitorum Superficialis transposition, a new technique for A2-C1 pulleys reconstruction: A kinematic cadaver study

INTRODUCTION

Homodigital flexor digitorum superficialis transposition (HFT) is proposed as a new technique for A2-C1 pulley reconstruction. Flexor digitorum superficialis is transposed on the proximal phalanx and inserted on the pulley rims, crossing over flexor digitorum profundus and acting as a pulley.

MATERIALS AND METHODS

The kinematic feasibility was investigated in a cadaveric bowstring model (after A2 and C1 pulley removal) on 22 fingers (thumb excluded).

RESULTS

HFT was effective in restoring the correct flexion of proximal and distal interphalangeal joints, compared to bowstring model. No adverse events were registered.

CONCLUSION

HFT is a feasible technique. Clinical application is encouraged.