Peter Jørgsholm

Rupture of the extensor pollicis longus tendon: a study of aetiological factors

Although rupture of the extensor pollicis longus (EPL) tendon is a wellknown complication of distal radial fractures, a number of patients rupture the EPL because of other conditions. We have retrospectively studied the aetiology of 27 ruptures of the EPL in 26 consecutive patients. Of 19 patients with injured wrists 12 had distal radial fractures, five had blunt trauma, and two had stab wounds that resulted in rupture. In the radial fractures operated on, the EPL rupture was caused by chafing against a dorsal plate (n = 2) or wear against the pins of an external fixator (n = 2). Six patients were taking steroids for systemic diseases and in two cases a local steroid injection was given just before the rupture. We conclude that previous injury is the most common cause of rupture of the EPL, but that rheumatoid arthritis or local or systemic steroids, or both, are also important aetiological factors. Seven patients had an iatrogenic cause for their rupture.

The incidence of intrinsic and extrinsic ligament injuries in scaphoid waist fractures.

PURPOSE To determine the incidence of associated intrinsic and extrinsic ligament injuries in patients with a nondisplaced or displaced scaphoid waist fracture. METHODS During a 3-year period, a study of all scaphoid fractures was performed at our institution. Diagnosis was confirmed by plain radiographs, computed tomography, and magnetic resonance imaging. A 3-part anatomic classification was used to categorize the scaphoid fractures. The study population comprised 40 patients with 41 scaphoid waist fractures who had wrist arthroscopy for treatment and evaluation of the scaphoid fracture and associated carpal injuries. RESULTS We observed fresh intrinsic ligament injuries in 34 of 41 wrists. In 29 cases, the scapholunate ligament was injured, with complete rupture occurring in 10 wrists. The lunotriquetral ligament was injured in 8 wrists, and the triangular fibrocartilage complex was injured in 11 wrists. Statistically, the number of intrinsic ligament injuries did not differ between nondisplaced and displaced scaphoid fractures (p> .30). CONCLUSIONS In this study of acute scaphoid waist fractures, the overall incidence of associated ligament injuries was surprisingly high, at 34 of 41 wrists. Complete scapholunate ligament rupture was found in 10 of 41 wrists. This incidence is higher than previously reported and emphasizes the need for careful assessment of the intrinsic and extrinsic ligaments, particularly the scapholunate ligament, before deciding on treatment.

Diagnostic Performance of Radiographs and Computed Tomography for Displacement and Instability of Acute Scaphoid Waist Fractures

BACKGROUND Fracture displacement is the most important factor associated with nonunion of a scaphoid waist fracture.We evaluated the performance characteristics of radiographs and computed tomography (CT) in the diagnosis of intraoperative displacement and instability of scaphoid waist fractures using wrist arthroscopy as the reference standard. METHODS During a six-year period (2004 to 2010) at two institutions, forty-four adult patients with a scaphoid waist fracture underwent arthroscopy-assisted operative fracture treatment at a mean of nine days (range, two to twenty-two days) after injury. Subjects included all of those with a displaced scaphoid fracture seen on radiographs and a selection of patients with a nondisplaced scaphoid fracture. All patients had preoperative radiographs and CT. Arthroscopy with up to 5 kg of traction was the reference standard for fracture displacement and instability. RESULTS The reference standard (arthroscopy) led to a diagnosis of twenty-two displaced fractures (all unstable) and twenty-two nondisplaced fractures (seven unstable). Displacement was diagnosed in eleven patients (25%) with the use of radiographs and in twenty (45%) with CT. The sensitivity, specificity, and accuracy for diagnosing intraoperative displacement were 45%, 95%, and 70%, respectively, with the use of radiographs and 77%, 86%, and 82%, respectively, with CT. The sensitivity, specificity, and accuracy for diagnosing intraoperative instability were 34%, 93%, and 55%, respectively,with the use of radiographs and 62%, 87%, and 70%, respectively, with CT. Assuming a 10% prevalence of fracture displacement and instability among all scaphoid waist fractures, the positive and negative predictive values for displacement were 53% and 94%, respectively, with the use of radiographs and 39% and 97% with CT whereas the positive and negative predictive values for instability were 36% and 93%, respectively, with radiographs and 34% and 95% with CT. CONCLUSIONS Radiographs and CT scans cannot be relied on to accurately diagnose intraoperative scaphoid fracture displacement or instability compared with arthroscopic examination. The influence, with regard to the risk of nonunion, of intraoperative instability of a scaphoid fracture that is seen to be nondisplaced on radiographs or CT is currently unknown. LEVEL OF EVIDENCE Diagnostic Level III.

The benefit of magnetic resonance imaging for patients with posttraumatic radial wrist tenderness.

PURPOSE To describe fractures revealed by magnetic resonance imaging (MRI) in a series of skeletally mature patients with radial wrist pain after an acute injury and clinically suspected to have a scaphoid fracture. Additionally, we attempted to assess the diagnostic value of radiographs and computed tomography (CT) in patients with scaphoid and other carpal fractures verified by MRI. METHODS We conducted the study prospectively over a 3-year period on skeletally mature patients presenting at our emergency department with tenderness on the radial side of the wrist after an injury. A total of 300 wrists in 296 patients underwent clinical and radiographic examination. We performed low-field, 0.23-T MRI of all injured wrists within 3 working days from inclusion in the study. If the radiographs or MRI revealed a scaphoid fracture, we immediately carried out a supplementary 16-slice CT scan of the wrist. We calculated the sensitivity and specificity of radiographs and CT for the diagnosis of scaphoid fractures using MRI as the reference standard. RESULTS We diagnosed a total of 224 fractures in 196 wrists using MRI; 42% were scaphoid fractures, 15% were distal radius fractures, 6% were triquetrum fractures, and 5% were capitate fractures. The most commonly found fracture combinations were that of the scaphoid and distal radius, followed by scaphoid and capitate fracture. The sensitivity of radiographs for visualization of scaphoid fractures was 70% and the specificity was 98%. Radiographic sensitivity for other fractures was less than 60%. The sensitivity of CT for visualization of scaphoid fractures was 95%, and between 75% and 100% for other fractures. CONCLUSIONS Low-field MRI showed a high incidence of fractures in patients with posttraumatic radial wrist tenderness and demonstrated more fractures than radiographs and CT. A scaphoid fracture was by far the most common injury. However, it is not clear whether diagnosis of subtle injuries only demonstrated on MRI improves outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE Diagnostic I.

Conservative Treatment Versus Arthroscopic-Assisted Screw Fixation of Scaphoid Waist Fractures-A Randomized Trial With Minimum 4-Year Follow-Up.

PURPOSE To evaluate clinical and radiological outcomes after conservative treatment and arthroscopic-assisted screw fixation of acute non- or minimally displaced scaphoid waist fractures in a randomized controlled trial. METHODS Consecutive patients with acute non- or minimally displaced scaphoid waist fractures were prospectively randomized to conservative or surgical treatment. All patients were screened using radiographs, computed tomography, and magnetic resonance imaging. Conservative treatment consisted of a below-elbow thumb spica cast until radiological signs of union appeared. Surgical treatment consisted of wrist arthroscopy and percutaneous antegrade screw fixation. Clinical examination, radiographs, and computed tomography were used to follow the patients. Twenty-four patients were treated conservatively and 14 patients underwent surgery. The patients were followed at regular intervals for 1 year after surgery. Twenty-one patients treated conservatively and 14 treated surgically were available for follow-up after a median of 6 years (range, 4-8 y). RESULTS At 26 weeks, the conservatively treated group had significantly better range of motion and had reached almost normal value compared with the contralateral wrist. There were no significant differences between the 2 groups concerning grip or pinch strengths at any measure point. At follow-up after a median of 6 years, radiographic signs of arthritis in the radioscaphoid joint were more common in the surgically treated group (3 of 14) than in the conservative group (2 of 21). CONCLUSIONS Non- and minimally displaced scaphoid waist fractures are best treated conservatively. Operative treatment may provide an improved functional outcome in the short term but at the price of a possible increased risk of arthritis in the long term. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic II.

Imaging of Four-Corner Fusion (SLAC Arthrodesis) of the Wrist with 64-Slice Computed Tomography.

Purpose: To find out whether it is possible to evaluate the healing of wrist arthrodesis, carried out with a metallic spider plate, by means of 64-slice computed tomography (CT). Material and Methods: 18 CT examinations were performed in 12 patients 2 weeks to 37 months following scapholunate advanced collapse (SLAC) arthrodesis fixed with a metallic plate. Ten patients also had plain films of the wrist. Radiation doses were estimated. Results: Plain films were difficult to evaluate due to overprojection of the spider plate. With 64-slice CT, however, it was possible to evaluate the healing process in all patients in spite of metallic artifacts. Radiation doses were low. Conclusion: The healing of SLAC arthrodesis of the wrist is difficult to evaluate with conventional radiography due to the metallic plate. By means of 64-slice CT, however, it was possible to “see under” the plate in all 12 patients.

Union of Scaphoid Waist Fractures Assessed by CT Scan.

Background Union of a scaphoid fracture is difficult to assess on a standard series of radiographs. An unnecessary and prolonged immobilization is inconvenient and may impair functional outcome. Although operative treatment permits early mobilization, its influence on time to union is still uncertain. Purpose To assess union of scaphoid waist fractures based on computed tomography (CT) scan at 6 weeks, and to compare time to union between conservative treatment and arthroscopically assisted screw fixation. Patients and methods CT scan in the longitudinal axis of the scaphoid was used to provide fracture characteristics, and to assess bone union at 6 weeks in 65 consecutive patients with scaphoid waist fractures. In a randomized subgroup from this cohort with nondisplaced fractures, we compared time to union between conservative treatment (n = 23) and arthroscopically assisted screw fixation (n = 15). Results Overall, at 6 weeks we found a 90% union rate for non- or minimally displaced fracture treated conservatively, and 82% for those who underwent surgery. In the randomized subgroup of nondisplaced fractures, no significant difference in time to union was demonstrated between those treated conservatively and those who underwent surgery. The conservatively treated fractures from this subgroup with prolonged time to union (10 to 14 weeks) were comminuted, demonstrating a radial cortical or corticospongious fragment. Conclusion The majority of non- or minimally displaced scaphoid waist fractures are sufficiently treated with 6 weeks in a cast. Screw fixation does not reduce time to fracture union compared with conservative treatment. Level of Evidence level II, Therapeutic study.

Factors Associated With Arthroscopically Determined Scaphoid Fracture Displacement and Instability

PURPOSE To identify factors associated with arthroscopically diagnosed scaphoid fracture displacement and instability. METHODS This was a secondary use of data from 2 prospective cohort studies. The studies included 58 consecutive adult patients with a scaphoid fracture who elected arthroscopy-assisted operative fracture treatment: some for displacement, some as part of a prospective protocol, and others to avoid a cast. All patients had preoperative computed tomography with reconstructions in planes defined by the long axis of the scaphoid. RESULTS Arthroscopy revealed 38 unstable fractures (movement between fracture fragments; 66%), 27 of which were also displaced. All arthroscopically determined displaced fractures were unstable, and 11 of the 31 arthroscopically determined, nondisplaced fractures were unstable. There was a significant correlation between radiographic comminution (more than 2 fracture fragments) and arthroscopically determined displacement and instability. CONCLUSIONS Radiographic comminution is associated with displacement and instability as determined by arthroscopy.

Osteonecrosis of the metacarpal head in a patient with a prothrombin 20210A gene mutation

Osteonecrosis of the metacarpal head is rare and of unknown cause. We describe a 17-year-old girl with osteonecrosis of the fourth metacarpal head and a mutated prothrombin 20210A gene, which suggests a possible relation between a hypercoagulable state and osteonecrosis of the metacarpal head.

MRI shows a high incidence of carpal fractures in children with posttraumatic radial-sided wrist tenderness

Background and purpose — The epidemiology and optimal diagnostics of wrist injuries in children are not knotwn. We describe fractures revealed by magnetic resonance imaging (MRI) in a prospective population of children and adolescents with posttraumatic radial-sided wrist tenderness, and compare the diagnostic value of radiographs and computed tomography (CT) with that of MRI. Patients and methods — From 2004 to 2007, patients less than 18 years of age who presented at our emergency department were included in the study. 90 wrists in 89 patients underwent clinical, radiographic, and low-field MRI investigation. If plain radiographs or MRI revealed a scaphoid fracture, a supplementary CT scan was performed. Sensitivity and specificity of radiographs and CT for diagnosis of scaphoid fractures was calculated using MRI as the reference standard. Results — 74 fractures were diagnosed in 61 of 90 wrists using MRI; 48 wrists had a scaphoid fracture, 8 had a distal radius fracture, 7 had a capitate fracture, and 3 had a triquetrum fracture. The most common combination of fractures was scaphoid and capitate. The sensitivity of radiographs for visualization of scaphoid fractures was 54% and the specificity was 100%. The sensitivity for other fractures was <50%. The sensitivity of CT for visualization of scaphoid fractures was 96% and it was between 33% and 100% for other fractures. Interpretation — MRI showed a high incidence of fractures in children and adolescents with posttraumatic radial wrist tenderness, and it led to the diagnosis of more fractures than plain radiographs and CT. A scaphoid fracture was the most common carpal injury, followed by fracture of the capitate.